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Sample records for bivalve mytilus edulis

  1. Characterization of the mantle transcriptome in bivalves: Pecten maximus, Mytilus edulis and Crassostrea gigas.

    Science.gov (United States)

    Yarra, Tejaswi; Gharbi, Karim; Blaxter, Mark; Peck, Lloyd S; Clark, Melody S

    2016-06-01

    The calcareous shells secreted by bivalve molluscs display diverse and species specific structural compositions, which indicates possible divergent biomineralization processes. Thus, studying multiple mollusc species will provide a more comprehensive understanding of shell formation. Here, the transcriptomes of the mantle tissues responsible for shell deposition were characterized in three commercially relevant bivalve species. Using high-throughput sequencing and bioinformatics tools, de novo transcriptome assemblies of mantle tissues were generated for the mussel Mytilus edulis, the oyster Crassostrea gigas and the scallop Pecten maximus. These transcriptomes were annotated, and contigs with similarity to proteins known to have shell formation roles in other species were identified. Comparison of the shell formation specific proteins in the three bivalves indicates the possibility of species specific shell proteins.

  2. Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?

    Science.gov (United States)

    Freitas, Pedro S.; Clarke, Leon J.; Kennedy, Hilary; Richardson, Christopher A.

    2016-12-01

    Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis

  3. Coexistence of Pacific oyster Crassostrea gigas (Thunberg, 1793) and blue mussels Mytilus edulis Linnaeus, 1758 on a sheltered intertidal bivalve bed?

    DEFF Research Database (Denmark)

    Holm, M.W.; Davids, J.K.; Dolmer, Per;

    2016-01-01

    The invasive Pacific oyster, Crassostrea gigas Thunberg, 1793 was introduced in Denmark for aquaculture in the 1970s. Presently, feral populations are found in many parts of the country, with the largest populations established on existing beds of blue mussel, Mytilus edulis Linnaeus, 1758...... and M. edulis were collected from the bivalve bed, shell lengths were converted into biomass, which were interpolated to create biomass contours and combined with modelled topography of the bivalve bed to study niche separation. The bivalve bed slowly extended northwards over a period of 11 years, where...

  4. Field clearance of an intertidal bivalve bed: relative significance of the co-occurring blue mussel Mytilus edulis and Pacific oyster Crassostrea gigas

    DEFF Research Database (Denmark)

    Vismann, Bent; Holm, Mark Wejlemann; Davids, Jens;

    2016-01-01

    At an approximately 12 000 m2 sheltered intertidal bivalve bed in the western part of the Limfjord, Denmark, the Pacific oyster Crassostrea gigas co-occurs with the blue mussel Mytilus edulis. The relative significance of the impact of the 2 species on phytoplankton density during a tidal cycle...

  5. Accumulation, elimination and chemical speciation of mercury in the bivalves Mytilus edulis and Macoma balthica

    DEFF Research Database (Denmark)

    Riisgård, H. U.; Kiørboe, Thomas; Møhlenberg, F.;

    1985-01-01

    Mussels (Mytilus edulis) transferred in net bags from clean to chronically mercury polluted water readily accumulated mercury during an exposure period of three months. Growth of the transplanted mussels had a “diluting” effect on the mercury concentration, but the absolute weight of mercury uptake...... increased throughout the entire period, though there was a tendency for decreased efficiency of the removal of mercury per liter of water filtered by the mussels. Mussels were also translocated from polluted to clean (laboratory) water to depurate mercury. The biological half-lives of mercury was 293 d...... for M. edulis from the chronically polluted area in contrast to only 53 d for mussels from a temporary massive mercury polluted area near a chemical deposit. In both cases about 75% of the total mercury in the mussels was inorganic, and it is suggested that both inorganic and organic mercury species...

  6. Complete sequences of the highly rearranged molluscan mitochondrial genomes of the scaphopod graptacme eborea and the bivalve mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Boore, Jeffrey L.; Medina, Monica; Rosenberg, Lewis A.

    2004-01-31

    We have determined the complete sequence of the mitochondrial genome of the scaphopod mollusk Graptacme eborea (Conrad, 1846) (14,492 nts) and completed the sequence of the mitochondrial genome of the bivalve mollusk Mytilus edulis Linnaeus, 1758 (16,740 nts). (The name Graptacme eborea is a revision of the species formerly known as Dentalium eboreum.) G. eborea mtDNA contains the 37 genes that are typically found and has the genes divided about evenly between the two strands, but M. edulis contains an extra trnM and is missing atp8, and has all genes on the same strand. Each has a highly rearranged gene order relative to each other and to all other studied mtDNAs. G. eborea mtDNA has almost no strand skew, but the coding strand of M. edulis mtDNA is very rich in G and T. This is reflected in differential codon usage patterns and even in amino acid compositions. G. eborea mtDNA has fewer non-coding nucleotides than any other mtDNA studied to date, with the largest non-coding region being only 24 nt long. Phylogenetic analysis using 2,420 aligned amino acid positions of concatenated proteins weakly supports an association of the scaphopod with gastropods to the exclusion of Bivalvia, Cephalopoda, and Polyplacophora, but is generally unable to convincingly resolve the relationships among major groups of the Lophotrochozoa, in contrast to the good resolution seen for several other major metazoan groups.

  7. Field clearance of an intertidal bivalve bed: relative significance of the co-occurring blue mussel Mytilus edulis and Pacific oyster Crassostrea gigas

    DEFF Research Database (Denmark)

    Vismann, Bent; Holm, Mark Wejlemann; Davids, Jens;

    2016-01-01

    At an approximately 12 000 m2 sheltered intertidal bivalve bed in the western part of the Limfjord, Denmark, the Pacific oyster Crassostrea gigas co-occurs with the blue mussel Mytilus edulis. The relative significance of the impact of the 2 species on phytoplankton density during a tidal cycle....... However, the estimated water column cleared during low tide is overestimated due to phytoplankton depletion. Hence, it is concluded that the bivalve bed clears the water close to 1 time each tidal cycle. This, together with a low dry weight of soft parts, indicates that the bivalve bed, in general...

  8. Coexistence of Pacific oyster Crassostrea gigas (Thunberg, 1793) and blue mussels Mytilus edulis Linnaeus, 1758 on a sheltered intertidal bivalve bed?

    DEFF Research Database (Denmark)

    Holm, M.W.; Davids, J.K.; Dolmer, Per;

    2016-01-01

    The invasive Pacific oyster, Crassostrea gigas Thunberg, 1793 was introduced in Denmark for aquaculture in the 1970s. Presently, feral populations are found in many parts of the country, with the largest populations established on existing beds of blue mussel, Mytilus edulis Linnaeus, 1758...

  9. Validation of the flooding dose technique to determine fractional rates of protein synthesis in a model bivalve species, the blue mussel (Mytilus edulis L.).

    Science.gov (United States)

    McCarthy, Ian D; Nicholls, Ruth; Malham, Shelagh K; Whiteley, Nia M

    2016-01-01

    For the first time, use of the flooding dose technique using (3)H-Phenylalanine is validated for measuring whole-animal and tissue-specific rates of protein synthesis in the blue mussel Mytilus edulis (61mm shell length; 4.0g fresh body mass). Following injection, the phenylalanine-specific radioactivities in the gill, mantle and whole-animal free pools were elevated within one hour and remained elevated and stable for up to 6h following injection of (3)H-phenylalanine into the posterior adductor muscle. Incorporation of (3)H-phenylalanine into body protein was linear over time following injection and the non-significant intercepts for the regressions suggested incorporation into body protein occurred rapidly after injection. These results validate the technique for measuring rates of protein synthesis in mussels. There were no differences in the calculated rates following 1-6h incubation in gill, mantle or whole-animal and fractional rates of protein synthesis from the combined time course data were 9.5±0.8%d(-1) for the gill, 2.5±0.3%d(-1) for the mantle and 2.6±0.3%d(-1) for the whole-animal, respectively (mean values±SEM). The whole-animal absolute rate of protein synthesis was calculated as 18.9±0.6mg protein day(-1). The use of this technique in measuring one of the major components of maintenance metabolism and growth will provide a valuable and convenient tool in furthering our understanding of the protein metabolism and energetics of this keystone marine invertebrate and its ability to adjust and respond to fluctuations, such as that expected as a result of climate change.

  10. Dynamic Energy Budget model parameter estimation for the bivalve Mytilus californianus: Application of the covariation method

    Science.gov (United States)

    Matzelle, A.; Montalto, V.; Sarà, G.; Zippay, M.; Helmuth, B.

    2014-11-01

    Dynamic Energy Budget (DEB) models serve as a powerful tool for describing the flow of energy through organisms from assimilation of food to utilization for maintenance, growth and reproduction. The DEB theory has been successfully applied to several bivalve species to compare bioenergetic and physiological strategies for the utilization of energy. In particular, mussels within the Mytilus edulis complex (M. edulis, M. galloprovincialis, and M. trossulus) have been the focus of many studies due to their economic and ecological importance, and their worldwide distribution. However, DEB parameter values have never been estimated for Mytilus californianus, a species that is an ecological dominant on rocky intertidal shores on the west coast of North America and which likely varies considerably from mussels in the M. edulis complex in its physiology. We estimated a set of DEB parameters for M. californianus using the covariation method estimation procedure and compared these to parameter values from other bivalve species. Model parameters were used to compare sensitivity to environmental variability among species, as a first examination of how strategies for physiologically contending with environmental change by M. californianus may differ from those of other bivalves. Results suggest that based on the parameter set obtained, M. californianus has favorable energetic strategies enabling it to contend with a range of environmental conditions. For instance, the allocation fraction of reserve to soma (κ) is among the highest of any bivalves, which is consistent with the observation that this species can survive over a wide range of environmental conditions, including prolonged periods of starvation.

  11. The exhalant jet of mussels Mytilus edulis

    DEFF Research Database (Denmark)

    Riisgard, Hans Ulrik; Jørgensen, Bo Hoffmann; Lundgreen, Kim

    2011-01-01

    shell lengths. Here, we present results of a detailed study of fully open mussels Mytilus edulis in terms of filtration rate, exhalant siphon aperture area, jet velocity, gill area and body dry weight, all as a function of shell length (mean +/- SD) over the range 16.0 +/- 0.4 to 82.6 +/- 2.9 mm......, with the corresponding scaling laws also presented. The exhalant jet velocity was determined by 3 methods: (1) measured clearance rate divided by exhalant aperture area, (2) manual particle tracking velocimetry (PTV) using video-microscope recordings, and (3) particle image velocimetry (PIV). The latter provides......), and independent of shell length. Based on geometric similarity and scaling of mussel pump-system characteristics we found that these characteristics coincide approximately for all sizes when expressed as pressure head versus volume flow divided by shell length squared....

  12. Mercury-binding proteins of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Roesijadi, G.; Morris, J. E.; Calabrese, A.

    1981-11-01

    Mytilus edulis possesses low molecular weight, mercury-binding proteins. The predominant protein isolated from gill tissue is enriched in cysteinyl residues (8%) and possesses an amino acid composition similar to cadmium-binding proteins of mussels and oysters. Continuous exposure of mussels to 5 ..mu..g/l mercury results in spillover of mercury from these proteins to high molecular weight proteins. Antibodies to these proteins have been isolated, and development of immunoassays is presently underway. Preliminary studies to determine whether exposure of adult mussels to mercury will result in induction of mercury-binding proteins in offspring suggest that such proteins occur in larvae although additional studies are indicated for a conclusive demonstration.

  13. Bioremediation of waste under ocean acidification: Reviewing the role of Mytilus edulis.

    Science.gov (United States)

    Broszeit, Stefanie; Hattam, Caroline; Beaumont, Nicola

    2016-02-15

    Waste bioremediation is a key regulating ecosystem service, removing wastes from ecosystems through storage, burial and recycling. The bivalve Mytilus edulis is an important contributor to this service, and is used in managing eutrophic waters. Studies show that they are affected by changes in pH due to ocean acidification, reducing their growth. This is forecasted to lead to reductions in M. edulis biomass of up to 50% by 2100. Growth reduction will negatively affect the filtering capacity of each individual, potentially leading to a decrease in bioremediation of waste. This paper critically reviews the current state of knowledge of bioremediation of waste carried out by M. edulis, and the current knowledge of the resultant effect of ocean acidification on this key service. We show that the effects of ocean acidification on waste bioremediation could be a major issue and pave the way for empirical studies of the topic.

  14. Accumulation of bis(tributyltin) oxide by the marine mussel Mytilus edulis. [Hytilus edulis; Isochrysis galbana

    Energy Technology Data Exchange (ETDEWEB)

    Laughlin, R.B. Jr.; French, W.; Guard, H.E.

    1986-09-01

    Marine mussels, primarily Mytilus edulis, accumulated bis(tributyltin) oxide (TBT) when it was either dissolved in water (0.5 ..mu..g L/sup -1/) or associated (absorbed or adsorbed) with phytoplankton Isochrysis galbana. Uptake occurred rapidly under both protocols but was more rapid and caused higher TBT burdens when accumulation occurred by ingestion of phytoplankton. TBT accumulated differentially in tissues. Highest burdens in viscera or gills were approx.4.5 ..mu..g of TBT (g of tissue)/sup -1/ following water exposure lasting 47 days and approx.5 ..mu..g of TBT (g of gill)/sup -1/ or (g of viscera tissue)/sup -1/ following 30 days of exposure to contaminated Isochrysis. This corresponds to a bioconcentration factor of approx.5000 from water but <2 from food (on a ..mu..g g/sup -1/ basis). Mantle or muscle tissue had TBT burdens one-half to one-third the level of viscera or gill tissue. Steady state between water and tissue was not observed. When TBT exposed mussels were returned to the field, t/sub 1/2/ for depuration was approx.14 days. Depuration rate constants estimated from uptake and release phases did not agree. This observation suggests differences in laboratory and field depuration processes by bivalve molluscs. Therefore, bioconcentration factor (BCF) measurements made in the laboratory may not accurately predict those obtained from environmental exposures. Neither humic acids nor kaolin significantly reduced accumulation of TBT.

  15. Common European harmful algal blooms affect the viability and innate immune responses of Mytilus edulis larvae.

    Science.gov (United States)

    De Rijcke, M; Vandegehuchte, M B; Vanden Bussche, J; Nevejan, N; Vanhaecke, L; De Schamphelaere, K A C; Janssen, C R

    2015-11-01

    Like marine diseases, harmful algal blooms (HABs) are globally increasing in frequency, severity and geographical scale. As a result, bivalves will have to face the combined threat of toxic algae and marine pathogens more frequently in the (near) future. These stressors combined may further affect the recruitment of ecologically and economically important bivalve species as HABs can affect the growth, viability and development of their larvae. To date, little is known on the specific effects of HABs on the innate immune system of bivalve larvae. This study therefore investigates whether two common harmful algae can influence the larval viability, development and immunological resilience of the blue mussel Mytilus edulis. Embryos of this model organism were exposed (48 h) to five densities of Pseudo-nitzschia multiseries or Prorocentrum lima cells. In addition, the effect of six concentrations of their respective toxins: domoic acid (DA) and okadaic acid (OA) were assessed. OA was found to significantly reduce larval protein phosphatase activity (p larval viability (p < 0.01) at concentrations as low as 37.8 μg l(-1). P. multiseries (1400 cells ml(-1)), P. lima (150 cells ml(-1)) and DA (dosed five times higher than typical environmental conditions i.e. 623.2 μg l(-1)) increased the phenoloxidase (PO) innate immune activity of the mussel larvae. These results suggest that the innate immune response of even the earliest life stages of bivalves is susceptible to the presence of HABs.

  16. Effect of copper on Mytilus californianus and Mytilus edulis. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-06

    Mytilus edulis and Mytilus californianus have come into widespread use as valuable test animals in estimating the effects and extent of copper pollution, both naturally as indicators and under simulated conditions as bioassays. These mussels are known bioaccumulators of heavy metals. They have a broad distribution, and mutually exclusive habitats. How the mussel reacts to copper is directly related to how copper affects the physiology of the mussel. The filtration rate and oxygen consumption of Mytilus are known to decline by more than 50% under exposure to as low as 200 ppB Cu in the water. Decline in heart rate (bradycardia) also occurs under exposure to copper. Byssus thread production suffers in copper concentrations of 500 ppB and higher. The ability of M. edulis to close its valves in the presence of copper has been documented by several researchers. Of all the physiological parameters, oxygen consumption, heart rate, and valve closure are basic physiological functions which are easily measured. Mortality of Mytilus edulis is known to occur at concentrations of copper 330 ppB and higher within four to five days. It would be advantageous to have a continuous monitoring of the heart, oxygen consumption, and valve gape during this period to determine the state of each and the contribution of each to the possible death of the mussel. This study involves monitoring the three above physiological functions under varying concentrations of copper. In both species, M. edulis and M. californianus, detailed toxicological response records were obtained for each function. These records were then used to compare the physiological responses of each species to different levels of ambient copper in order to explain the possibility of repeatable, species-specific, response patterns to copper. (ERB)

  17. Oxidative stress and toxicity of gold nanoparticles in Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Tedesco, Sara [Environmental Research Institute of University College Cork, Cork (Ireland); Doyle, Hugh [Tyndall National Institute, Cork (Ireland); Blasco, Julian [Consejo Superior de Investigaciones Cientificas (CSIC), Marine Science Institute of Andalusia, Cadiz (Spain); Redmond, Gareth [Tyndall National Institute, Cork (Ireland); Sheehan, David, E-mail: d.sheehan@ucc.ie [Environmental Research Institute of University College Cork, Cork (Ireland)

    2010-10-15

    Gold nanoparticles (AuNP) have potential applications in drug delivery, cancer diagnosis and therapy, food industry and environment remediation. However, little is known about their potential toxicity or fate in the environment. Mytilus edulis was exposed in tanks to750 ppb AuNP (average diameter 5.3 {+-} 1 nm) for 24 h to study in vivo biological effects of nanoparticles. Traditional biomarkers and an affinity procedure selective for thiol-containing proteins followed by two-dimensional electrophoresis (2DE) separations were used to study toxicity and oxidative stress responses. Results were compared to those obtained for treatment with cadmium chloride, a well known pro-oxidant. M. edulis mainly accumulated AuNP in digestive gland which also showed higher lipid peroxidation. One-dimensional SDS/PAGE (1DE) and 2DE analysis of digestive gland samples revealed decreased thiol-containing proteins for AuNP. Lysosomal membrane stability measured in haemolymph gave lower values for neutral red retention time (NRRT) in both treatments but was greater in AuNP. Oxidative stress occurred within 24 h of AuNP exposure in M. edulis. Previously we showed that larger diameter AuNP caused modest effects, indicating that nanoparticle size is a key factor in biological responses to nanoparticles. This study suggests that M. edulis is a suitable model animal for environmental toxicology studies of nanoparticles.

  18. Massively parallel RNA sequencing identifies a complex immune gene repertoire in the lophotrochozoan Mytilus edulis.

    Directory of Open Access Journals (Sweden)

    Eva E R Philipp

    Full Text Available The marine mussel Mytilus edulis and its closely related sister species are distributed world-wide and play an important role in coastal ecology and economy. The diversification in different species and their hybrids, broad ecological distribution, as well as the filter feeding mode of life has made this genus an attractive model to investigate physiological and molecular adaptations and responses to various biotic and abiotic environmental factors. In the present study we investigated the immune system of Mytilus, which may contribute to the ecological plasticity of this species. We generated a large Mytilus transcriptome database from different tissues of immune challenged and stress treated individuals from the Baltic Sea using 454 pyrosequencing. Phylogenetic comparison of orthologous groups of 23 species demonstrated the basal position of lophotrochozoans within protostomes. The investigation of immune related transcripts revealed a complex repertoire of innate recognition receptors and downstream pathway members including transcripts for 27 toll-like receptors and 524 C1q domain containing transcripts. NOD-like receptors on the other hand were absent. We also found evidence for sophisticated TNF, autophagy and apoptosis systems as well as for cytokines. Gill tissue and hemocytes showed highest expression of putative immune related contigs and are promising tissues for further functional studies. Our results partly contrast with findings of a less complex immune repertoire in ecdysozoan and other lophotrochozoan protostomes. We show that bivalves are interesting candidates to investigate the evolution of the immune system from basal metazoans to deuterostomes and protostomes and provide a basis for future molecular work directed to immune system functioning in Mytilus.

  19. Correlation of transcriptomic responses and metal bioaccumulation in Mytilus edulis L. reveals early indicators of stress

    Energy Technology Data Exchange (ETDEWEB)

    Poynton, Helen C., E-mail: helen.poynton@umb.edu; Robinson, William E.; Blalock, Bonnie J.; Hannigan, Robyn E.

    2014-10-15

    Highlights: • Gene expression and metal tissue concentrations were compared in Mytilus edulis. • Expression levels of several transcripts correlated with metal concentrations. • Transcripts involved in the unfolded protein response (UPR) were induced. • Integration of transcriptomics and tissue levels provides insight to toxicity. - Abstract: Marine biomonitoring programs in the U.S. and Europe have historically relied on monitoring tissue concentrations of bivalves to monitor contaminant levels and ecosystem health. By integrating ‘omic methods with these tissue residue approaches we can uncover mechanistic insight to link tissue concentrations to potential toxic effects. In an effort to identify novel biomarkers and better understand the molecular toxicology of metal bioaccumulation in bivalves, we exposed the blue mussel, Mytilus edulis L., to sub-lethal concentrations (0.54 μM) of cadmium, lead, and a Cd + Pb mixture. Metal concentrations were measured in gill tissues at 1, 2, and 4 weeks, and increased linearly over the 4 week duration. In addition, there was evidence that Pb interfered with Cd uptake in the mixture treatment. Using a 3025 sequence microarray for M. edulis, we performed transcriptomic analysis, identifying 57 differentially expressed sequences. Hierarchical clustering of these sequences successfully distinguished the different treatment groups demonstrating that the expression profiles were reproducible among the treatments. Enrichment analysis of gene ontology terms identified several biological processes that were perturbed by the treatments, including nucleoside phosphate biosynthetic processes, mRNA metabolic processes, and response to stress. To identify transcripts whose expression level correlated with metal bioaccumulation, we performed Pearson correlation analysis. Several transcripts correlated with gill metal concentrations including mt10, mt20, and contig 48, an unknown transcript containing a wsc domain. In addition

  20. Composition and ultrastructure of the byssus of Mytilus edulis.

    Science.gov (United States)

    Benedict, C V; Waite, J H

    1986-09-01

    Three regions of the byssus of the marine mussel Mytilus edulis L. are distinct in structural organization at the macroscopic and microscopic level and in amino acid composition. The threads that emanate from the stem at the base of the foot are divided into two regions. The proximal, elastic region has a crimped, densely staining cortex enclosing an interior matrix of spiral fibers, and its amino acid composition reflects protein heterogeneity. The more distal, rigid region has a straight, tubular cortex surrounding an inner matrix of linearly arranged bundles of fibrils and has a composition approximating pure collagen. The plaque, or disc-shaped portion, which mediates attachment to various substrates, is distinguished by a surface matrix of collagen-like fibers similar to those of the thread region and anchored on an inner spongy matrix. Compositional evidence exists for a collagenous component, a catechol-rich protein, and at least one other accessory protein in the plaque.

  1. Dopamine receptor in anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Takayanagi, I; Murakami, H; Iwayama, Y; Yoshida, Y; Miki, S

    1981-04-01

    Effects of dopamine, N-methyl-, ethyl- and propyl-derivatives of dopamine, and alpha- and beta-adrenoceptor stimulants on catch contraction of anterior byssus retractor muscle of Mytilus edulis were tested. The test drugs except the beta-adrenoceptor stimulants relaxed catch contraction. Dopamine was most active and substitution of amino group in dopamine with ethyl and propyl decreased activity considerably. The concentration-curves of dopamine, its derivatives and norepinephrine shifted in parallel with application of haloperidol but were not influenced by the alpha- and beta-adrenoceptor antagonists. These results suggest that relaxation of catch contraction by catecholamines is mediated through a dopamine receptor. This muscle is considered to be suitable for a study of the dopamine receptor.

  2. Genetic hitchhiking in a subdivided population of Mytilus edulis

    Directory of Open Access Journals (Sweden)

    David Patrice

    2008-05-01

    Full Text Available Abstract Background Few models of genetic hitchhiking in subdivided populations have been developed and the rarity of empirical examples is even more striking. We here provide evidences of genetic hitchhiking in a subdivided population of the marine mussel Mytilus edulis. In the Bay of Biscay (France, a patch of M. edulis populations happens to be separated from its North Sea conspecifics by a wide region occupied only by the sister species M. galloprovincialis. Although genetic differentiation between the two M. edulis regions is largely non-significant at ten marker loci (average FST~0.007, a strong genetic differentiation is observed at a single locus (FST = 0.25. We validated the outlier status of this locus, and analysed DNA sequence polymorphism in order to identify the nature of the selection responsible for the unusual differentiation. Results We first showed that introgression of M. galloprovincialis alleles was very weak in both populations and did not significantly affect their differentiation. Secondly, we observed the genetic signature of a selective sweep within both M. edulis populations in the form of a star-shaped clade of alleles. This clade was nearly fixed in the North Sea and was segregating at a moderate frequency in the Bay of Biscay, explaining their genetic differentiation. Incomplete fixation reveals that selection was not direct on the locus but that the studied sequence recombined with a positively selected allele at a linked locus while it was on its way to fixation. Finally, using a deterministic model we showed that the wave of advance of a favourable allele at a linked locus, when crossing a strong enough barrier to gene flow, generates a step in neutral allele frequencies comparable to the step observed between the two M. edulis populations at the outlier locus. In our case, the position of the barrier is now materialised by a large patch of heterospecific M. galloprovincialis populations. Conclusion High FST

  3. Ocean acidification alters the material properties of Mytilus edulis shells.

    Science.gov (United States)

    Fitzer, Susan C; Zhu, Wenzhong; Tanner, K Elizabeth; Phoenix, Vernon R; Kamenos, Nicholas A; Cusack, Maggie

    2015-02-01

    Ocean acidification (OA) and the resultant changing carbonate saturation states is threatening the formation of calcium carbonate shells and exoskeletons of marine organisms. The production of biominerals in such organisms relies on the availability of carbonate and the ability of the organism to biomineralize in changing environments. To understand how biomineralizers will respond to OA the common blue mussel, Mytilus edulis, was cultured at projected levels of pCO2 (380, 550, 750, 1000 µatm) and increased temperatures (ambient, ambient plus 2°C). Nanoindentation (a single mussel shell) and microhardness testing were used to assess the material properties of the shells. Young's modulus (E), hardness (H) and toughness (KIC) were measured in mussel shells grown in multiple stressor conditions. OA caused mussels to produce shell calcite that is stiffer (higher modulus of elasticity) and harder than shells grown in control conditions. The outer shell (calcite) is more brittle in OA conditions while the inner shell (aragonite) is softer and less stiff in shells grown under OA conditions. Combining increasing ocean pCO2 and temperatures as projected for future global ocean appears to reduce the impact of increasing pCO2 on the material properties of the mussel shell. OA may cause changes in shell material properties that could prove problematic under predation scenarios for the mussels; however, this may be partially mitigated by increasing temperature.

  4. Ocean acidification and host-pathogen interactions: blue mussels, Mytilus edulis, encountering Vibrio tubiashii.

    Science.gov (United States)

    Asplund, Maria E; Baden, Susanne P; Russ, Sarah; Ellis, Robert P; Gong, Ningping; Hernroth, Bodil E

    2014-04-01

    Ocean acidification (OA) can shift the ecological balance between interacting organisms. In this study, we have used a model system to illustrate the interaction between a calcifying host organism, the blue mussel Mytilus edulis and a common bivalve bacterial pathogen, Vibrio tubiashii, with organisms being exposed to a level of acidification projected to occur by the end of the 21st century. OA exposures of the mussels were carried out in relative long-term (4 months) and short-term (4 days) experiments. We found no effect of OA on the culturability of V. tubiashii, in broth or in seawater. OA inhibited mussel shell growth and impaired crystalline shell structures but did not appear to affect mussel immune parameters (i.e haemocyte counts and phagocytotic capacity). Despite no evident impact on host immunity or growth and virulence of the pathogen, V. tubiashii was clearly more successful in infecting mussels exposed to long-term OA compared to those maintained under ambient conditions. Moreover, OA exposed V. tubiashii increased their viability when exposed to haemocytes of OA-treated mussel. Our findings suggest that even though host organisms may have the capacity to cope with periods of OA, these conditions may alter the outcome of host-pathogen interactions, favouring the success of the latter.

  5. Colloidal complexed silver and silver nanoparticles in extrapallial fluid of Mytilus edulis.

    Science.gov (United States)

    Zuykov, Michael; Pelletier, Emilien; Demers, Serge

    2011-02-01

    Metal transport in mollusk extrapallial fluid (EPF) that acts as a "bridge" between soft tissues and shell has surprisingly received little attention until now. Using ultrafiltration and radiotracer techniques we determined silver concentrations and speciation in the EPF of the blue mussel Mytilus edulis after short-term uptake and depuration laboratory experiments. Radiolabelled silver ((¹¹⁰m)Ag) was used in dissolved or nanoparticulate phases (AgNPs silver nanoparticles were transported to the EPF of blue mussels at a level similar to the Ag ionic form. Bulk activity of radiolabelled silver in the EPF represented only up to 7% of the bulk activity measured in the whole mussels. The EPF extracted from mussels exposed to both treatments exhibited an Ag colloidal complexed form based on EPF ultrafiltration through a 3 kDa filter. This original study brings new insights to internal circulation of nanoparticles in living organisms and contributes to the international effort in studying the potential impacts of engineered nanomaterials on marine bivalves which play an essential role in coastal ecosystems, and are important contributors to human food supply from the sea.

  6. The subfossil occurrence of Mytilus edulis L. in central East Greenland

    DEFF Research Database (Denmark)

    Hjort, Christian; Funder, Svend Visby

    1974-01-01

    The subfossil occurrence of Mytilus edulis in central East Greenland has been CH-dated to roughly between 8000 B.P. and 5500 B.P.; compared with other areas this is a short period. Its immigration coincides with the final deglaciation of the innermost fjords, and its disappearance is contemporane...... islandica can or could live, even if this was not possible along the surrounding and more hostile outer coasts. The reason for the absence of Mytilus edulis from the region today is probably not the local climate....

  7. Future oceanic warming and acidification alter immune response and disease status in a commercial shellfish species, Mytilus edulis L.

    Directory of Open Access Journals (Sweden)

    Clara L Mackenzie

    Full Text Available Increases in atmospheric carbon dioxide are leading to physical changes in marine environments including parallel decreases in ocean pH and increases in seawater temperature. This study examined the impacts of a six month exposure to combined decreased pH and increased temperature on the immune response and disease status in the blue mussel, Mytilus edulis L. Results provide the first confirmation that exposure to future acidification and warming conditions via aquarium-based simulation may have parallel implications for bivalve health. Collectively, the data suggests that temperature more than pH may be the key driver affecting immune response in M. edulis. Data also suggests that both increases in temperature and/or lowered pH conditions may lead to changes in parasite abundance and diversity, pathological conditions, and bacterial incidence in M. edulis. These results have implications for future management of shellfish under a predicted climate change scenario and future sustainability of shellfisheries. Examination of the combined effects of two stressors over an extended exposure period provides key preliminary data and thus, this work represents a unique and vital contribution to current research efforts towards a collective understanding of expected near-future impacts of climate change on marine environments.

  8. Intersex in Littorina littorea and DNA damage in Mytilus edulis as indicators of harbour polllution

    DEFF Research Database (Denmark)

    Rank, Jette

    2009-01-01

    Intersex in snails (Littorina littorea) and DNA damage in blue mussels (Mytilus edulis) were analysed to assess how these bio-indicators reflected the level of chemical contamination at two sites in a highly contaminated harbour in Denmark. The comet assay using mussel gill cells was an indicator...... effects were found to reflect the levels of the chemicals, and it was concluded that intersex in L. littorea and DNA damage in M. edulis can be used as bio-indicators of harbour pollution...

  9. Effects of chemical contaminants on growth, age-structure, and reproduction of Mytilus edulis complex from Puget sound, Washington.

    Science.gov (United States)

    Kagley, Anna N; Kardong, Kyle E; Snider, Robert G; Casillas, Edmundo

    2014-07-01

    Bivalves are used as sentinel species to detect chemical contaminants in the marine environment, but biological effects on indigenous populations that result from chemical exposure are largely unknown. We assessed age-weight, length-weight relationships, age structure, and reproductive status (i.e. fecundity, egg size) of the blue mussel Mytilus edulis complex from six sites in central Puget Sound, Washington, and one site in the relatively pristine area of northern Puget Sound. Results of this study suggest that mussels from urban areas of Puget Sound exhibit a lower growth rate, altered population age-structure, and potential reproductive impairment as a result of exposure to chemical contaminants. These findings support the use of mussels as sentinel species to assess the biological effects of contaminants on invertebrate populations.

  10. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    NARCIS (Netherlands)

    Kangeri, A.K.; Jansen, J.M.; Barkman, B.R.; Donker, J.J.A.; Joppe, D.J.; Dankers, N.M.J.A.

    2014-01-01

    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal

  11. Pertubation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    NARCIS (Netherlands)

    wa Kangeri, A.K.; Jansen, J.M.; Barkman, B.R.; Donker, J. J. A.; Joppe, D.J.; Dankers, N.M.J.A.

    2014-01-01

    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal

  12. Mytilus edulis haemocytes variability: technique, individual, and environment?

    DEFF Research Database (Denmark)

    Jouvet, Lionel

    . Eosinophils are found in large numbers in epithelial association in the gills, guts and in the mantle, where their numbers have been evaluated at 3x107 As a case study, Mytilus edulis challenged with barium sulphate smothering, used by the oil industry in drilling muds, shows gill damage and their subsequent...

  13. Comparison of trace metal bioavailabilities in European coastal waters using mussels from Mytilus edulis

    NARCIS (Netherlands)

    Przytarska, J.E.; Sokolowski, A.; Wolowicz, M.; Hummel, H.; Jansen, J.M.

    2010-01-01

    Mussels from Mytilus edulis complex were used as biomonitors of the trace metals Fe, Mn, Pb, Zn, and Cu at 17 sampling sites to assess the relative bioavailability of metals in coastal waters around the European continent. Because accumulated metal concentrations in a given area can differ temporall

  14. Seasonal variability in nutrient regeneration by mussel Mytilus edulis rope culture in oligotrophic systems

    NARCIS (Netherlands)

    Jansen, H.M.; Strand, O.; Strohmeier, T.; Krogness, C.; Verdegem, M.C.J.; Smaal, A.C.

    2011-01-01

    Blue mussel Mytilus edulis cultures contribute to nutrient cycling in coastal ecosystems. Mussel populations filter particulate nutrients from the water column and inorganic nutrients are regenerated by excretion of metabolic wastes and decomposition of (pseudo-)faeces. The objective of this study w

  15. The interactions between bed structure of Mytilus edulis L. and the predator Asterias rubens L

    DEFF Research Database (Denmark)

    Dolmer, Per

    1998-01-01

    The feeding behaviour of asteroids is usually analyzed with optimal foraging models, which assume that asteroids maximize the ratio of energy uptake relative to energy used in the feeding process. The behaviour of Asterias rubens feeding at subtidal beds of Mytilus edulis was studied in order...

  16. Optimization of blue mussel (Mytilus edulis) seed culture using recirculation aquaculture systems

    NARCIS (Netherlands)

    Blanco Garcia, A.; Kamermans, P.

    2015-01-01

    By introducing recirculation aquaculture systems (RAS) in the nursery phase of the blue mussel (Mytilus edulis) (17–18 mm), we aimed at a similar growth and survival and a similar water quality compared to the commonly used flow-through systems (FTS). To calculate water flow and size of the biofilte

  17. Inter- and intra-specimen variability masks reliable temperature control on shell Mg/Ca ratios in laboratory and field cultured Mytilus edulis and Pecten maximus (bivalvia

    Directory of Open Access Journals (Sweden)

    H. A. Kennedy

    2008-02-01

    Full Text Available The Mg/Ca ratios of biogenic calcites are commonly seen as a valuable palaeo-proxy for reconstructing past ocean temperatures. The temperature dependence of Mg/Ca ratios in bivalve calcite has been the subject of contradictory observations. The palaeoceanographic use of a geochemical proxy, like Mg/Ca ratios, is dependent on initial, rigorous calibration and validation of relationships between the proxy and the ambient environmental variable to be reconstructed. Shell Mg/Ca ratio data are reported for the calcite of two bivalve species, Mytilus edulis (common mussel and Pecten maximus (king scallop, for the first time grown in laboratory culturing experiments at controlled and constant aquarium seawater temperatures over a range from ~10 to ~20°C. Furthermore, Mg/Ca ratio data of laboratory-grown and field-grown M. edulis specimens were compared. Only a weak, albeit significant, shell Mg/Ca ratio–temperature relationship was observed in the two bivalve species: M. edulis (r2=0.37, pr2=0.50, pP. maximus (r2=0.21, p<0.001, laboratory cultured specimens only. In the two species, shell Mg/Ca ratios also were not found to be controlled by shell growth rate and salinity. Furthermore, measurement of Mg/Ca ratios in the shells of multiple specimens illustrated that a large degree of variability in the measured shell Mg/Ca ratios was significant at the species, inter- and intra-individual shell levels. The study data suggest the use of bivalve calcite Mg/Ca ratios as a reliable, precise and accurate temperature proxy still remains limited, at least in the species studied to date. Such limitations are most likely due to the presence of significant physiological effects on Mg incorporation in bivalve calcite, with such variability differing both within single shells and between shells of the same species that were precipitated under the same ambient conditions.

  18. Resource subsidies from multi-trophic aquaculture affect isotopic niche width in wild blue mussels (Mytilus edulis)

    Science.gov (United States)

    Weldrick, C. K.; Jelinski, D. E.

    2016-05-01

    Blue mussels (Mytilus edulis) are boreo-temperate, filter-feeding bivalves common to intertidal areas. As filter-feeders they have been employed in open-water, multi-tropic aquaculture systems to reduce organic benthic loading though the exploitation of suspended particulate organic materials. We compared δ13C and δ15N signatures and the isotopic niches of mussels growing in, and adjacent to, an integrated multi-trophic aquaculture (IMTA) farm in British Columbia, Canada, and using this information evaluated the contribution of aquaculture-derived effluent to their diet. Farm-sampled mussels had the least intraspecific isotopic variation compared to mussels sampled at the reference site. The interaction between time (i.e. sampling dates) and site did not significantly affect the isotopic composition of mussels; however significant variation was detected in δ15N values as a function of sampling date and particulate organic matter. A two-source isotopic mixing model indicated that marine particulate organic matter and IMTA farm effluent were approximately equal in importance (~ 46 % and ~ 54 %, respectively) to the diet of IMTA-retrieved mussels. Uptake of IMTA farm waste by M. edulis supports their use as economic extractives while also mitigating farmed sablefish (Anoplopoma fimbria) nutrient loading to the aquatic environment.

  19. Mitogenomics of southern hemisphere blue mussels (Bivalvia: Pteriomorphia): Insights into the evolutionary characteristics of the Mytilus edulis complex

    Science.gov (United States)

    Gaitán-Espitia, Juan Diego; Quintero-Galvis, Julian F.; Mesas, Andres; D’Elía, Guillermo

    2016-01-01

    Marine blue mussels (Mytilus spp.) are widespread species that exhibit an antitropical distribution with five species occurring in the Northern Hemisphere (M. trossulus, M. edulis, M. galloprovincialis, M. californianus and M. coruscus) and three in the Southern Hemisphere (M. galloprovincialis, M. chilensis and M. platensis). Species limits in this group remain controversial, in particular for those forms that live in South America. Here we investigated structural characteristics of marine mussels mitogenomes, based on published F mtDNA sequences of Northern Hemisphere species and two newly sequenced South American genomes, one from the Atlantic M. platensis and another from the Pacific M. chilensis. These mitogenomes exhibited similar architecture to those of other genomes of Mytilus, including the presence of the Atp8 gene, which is missing in most of the other bivalves. Our evolutionary analysis of mitochondrial genes indicates that purifying selection is the predominant force shaping the evolution of the coding genes. Results of our phylogenetic analyses supported the monophyly of Pteriomorphia and fully resolved the phylogenetic relationships among its five orders. Finally, the low genetic divergence of specimens assigned to M. chilensis and M. platensis suggests that these South American marine mussels represent conspecific variants rather than distinct species. PMID:27241855

  20. Effect of ocean acidification on the early life stages of the blue mussel (Mytilus edulis

    Directory of Open Access Journals (Sweden)

    C. H. R. Heip

    2010-04-01

    Full Text Available Several experiments have shown a decrease of growth and calcification of organisms at decreased pH levels but relatively few studies have focused on early life stages which are believed to be more sensitive to environmental disturbances such as hypercapnia. Here, we present experimental data demonstrating that the growth of planktonic mussel (Mytilus edulis larvae is significantly affected by a decrease of pH to a level expected for the end of the century. Even though there was no significant effect of a 0.25–0.34 pH unit decrease on hatching and mortality rates during the first 2 days of development nor during the following 13-day period prior to settlement, final shells were, respectively, 4.5±1.3 and 6.0±2.3% smaller at pHNBS~7.8 than at a control pHNBS of ~8.1. Moreover, a decrease of 12.0±5.4% of shell thickness was observed. More severe impacts were found with a decrease of ~0.5 pHNBS unit during the first 2 days of development which could be attributed to a decrease of calcification due toslight undersaturation of seawater with respect to aragonite. Indeed, important effects on both hatching and D-veliger shell growth were found. Hatching rates were 24±4% lower while D-veliger shells were 12.7±0.9% smaller at pHNBS~7.6 than at a control pHNBS of ~8.1. Although these results show that blue mussel larvae are still able to develop a shell in seawater undersaturated with respect to aragonite, decreases of hatching rates and shell growth suggest a negative impact of ocean acidification on the future survival of bivalve populations potentially leading to significant ecological and economical losses.

  1. Alteration of shell nacre micromorphology in blue mussel Mytilus edulis after exposure to free-ionic silver and silver nanoparticles.

    Science.gov (United States)

    Zuykov, Michael; Pelletier, Emilien; Belzile, Claude; Demers, Serge

    2011-07-01

    This study describes the morphology of inner shell surface (ISS) of the blue mussel Mytilus edulis Linnaeus after short-term exposures to radiolabeled silver in free-ionic ((110m)Ag(+)) and engineered nanoparticulate ((110m)AgNPs, <40 nm) phases. Radiolabeled silver in starting solutions was used in a similar low concentration (∼15 Bq mL(-1)) for both treatments. After exposure experiments radiolabeled silver was leached from the ISS using HCl. It concentration for shells from both treatments was ∼0.5 Bq mL(-1). Whole ISS of young individuals and prismatic layer of adults showed no evidence of any major alteration process after silver uptake. However, the nacre portion of adult mussels exposed to both treatments revealed distinct doughnut shape structures (DSS) formed by calcium carbonate micrograins that covered the surface of aragonite tablets. Scanning electron microscope (SEM) imaging revealed the existence of only minor differences in DSS morphology between mussels exposed to Ag(+) and AgNPs. From literature survey, DSS were also found in bivalves exposed to Cd(2+). The DSS occurring in a specimen of a field-collected bivalve is also shown. Formation of distinctive DSS can be explained by a disturbance of the shell calcification mechanism. Although the occurrence of DSS is not exclusively associated with metal bioavailability to the mussels, the morphology of DSS seems to be linked to the speciation of the metal used in the uptake experiments.

  2. Neurotransmitters and neuromodulators controlling the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Muneoka, Y; Fujisawa, Y; Matsuura, M; Ikeda, T

    1991-01-01

    1. The anterior byssus retractor muscle (ABRM) of Mytilus edulis is innervated by at least two kinds of nerves, excitatory and relaxing nerves. The principal neurotransmitters released from these nerves have been shown to be acetylcholine and serotonin, respectively. 2. Some other monoamines, such as dopamine and octopamine, and various peptides, such as FMRFamide-related peptides, Mytilus inhibitory peptides, SCP-related peptides and a catch-relaxing peptide, may also be involved in the regulation of the muscle as neurotransmitters or neuromodulators. 3. The ABRM seems to be typical of invertebrate muscles controlled by multiple neurotransmitters and neuromodulators.

  3. The ocean is not deep enough: pressure tolerances during early ontogeny of the blue mussel Mytilus edulis.

    Science.gov (United States)

    Mestre, Nélia C; Thatje, Sven; Tyler, Paul A

    2009-02-22

    Early ontogenetic adaptations reflect the evolutionary history of a species. To understand the evolution of the deep-sea fauna and its adaptation to high pressure, it is important to know the effects of pressure on their shallow-water relatives. In this study we analyse the temperature and pressure tolerances of early life-history stages of the shallow-water species Mytilus edulis. This species expresses a close phylogenetic relationship with hydrothermal-vent mussels of the subfamily Bathymodiolinae. Tolerances to pressure and temperature are defined in terms of fertilization success and embryo developmental rates in laboratory-based experiments. In M. edulis, successful fertilization under pressure is possible up to 500 atm (50.66 MPa), at 10, 15 and 20 degrees C. A slower embryonic development is observed with decreasing temperature and with increasing pressure; principally, pressure narrows the physiological tolerance window in different ontogenetic stages of M. edulis, and slows down metabolism. This study provides important clues on possible evolutionary pathways of hydrothermal vent and cold-seep bivalve species and their shallow-water relatives. Evolution and speciation patterns of species derive mostly from their ability to adapt to variable environmental conditions, within environmental constraints, which promote morphological and genetic variability, often differently for each life-history stage. The present results support the view that a direct colonization of deep-water hydrothermal vent environments by a cold eurythermal shallow-water ancestor is indeed a possible scenario for the Mytilinae, challenging previous hypothesis of a wood/bone to seep/vent colonization pathway.

  4. Toll signal transduction pathway in bivalves: complete cds of intermediate elements and related gene transcription levels in hemocytes of immune stimulated Mytilus galloprovincialis.

    Science.gov (United States)

    Toubiana, Mylène; Rosani, Umberto; Giambelluca, Sonia; Cammarata, Matteo; Gerdol, Marco; Pallavicini, Alberto; Venier, Paola; Roch, Philippe

    2014-08-01

    Based on protein domain structure and organization deduced from mRNA contigs, 15 transcripts of the Toll signaling pathway have been identified in the bivalve, Mytilus galloprovincialis. Identical searches performed on publicly available Mytilus edulis ESTs revealed 11 transcripts, whereas searches performed in genomic and new transcriptome sequences of the Pacific oyster, Crassostrea gigas, identified 21 Toll-related transcripts. The remarkable molecular diversity of TRAF and IKK coding sequences of C. gigas, suggests that the sequence data inferred from Mytilus cDNAs may not be exhaustive. Most of the Toll pathway genes were constitutively and ubiquitously expressed in M. galloprovincialis, although at different levels, and clearly induced after in vivo injection with bacteria. Such over-transcription was more rapid and intense with Gram-negative than with Gram-positive bacteria. Injection of a fungus modulated the transcription of few Toll pathway genes, with the induction levels of TLR/MyD88 complex being always less intense. Purified LPS and β-glucans had marginal effect whereas peptidoglycans were ineffective. At the moment, we found no evidence of an IMD transcript in bivalves. In conclusion, mussels possess a complete Toll pathway which can be triggered either by Gram-positive or Gram-negative bacteria.

  5. Effects of nanopolystyrene on the feeding behavior of the blue mussel (Mytilus edulis L.).

    Science.gov (United States)

    Wegner, A; Besseling, E; Foekema, E M; Kamermans, P; Koelmans, A A

    2012-11-01

    As the industrial production of nanoplastic and the degradation of microplastic into smaller particles at sea increase, the potential amount of nanoplastics in the marine environment rises. It has been reported that mussels uptake 100-nm polystyrene (PS) beads; to date, however, the effects of this uptake on the organism are unknown. In the present study, the authors investigated the effects of 30-nm PS on the feeding behavior of the blue mussel (Mytilus edulis) by exposing the organism to different nano PS and different algae (Pavlova lutheri) concentrations. The state of nano PS aggregation in the exposure medium was assessed using dynamic light scattering. In all treatments that contained nano PS, M. edulis produced pseudofeces. The total weight of the feces and pseudofeces increased with increasing nano PS and increasing algae concentration. Furthermore, M. edulis reduced its filtering activity when nano PS was present but still caused a decrease in the apparent nano PS concentration in the water. The presence of nano PS around the foot of M. edulis after the bioassay confirmed that the organism removed nano PS from the water. Chronic effect studies are therefore needed to investigate the effects of nanoplastics in M. edulis and possible consequences for its predators, including humans.

  6. A molecular, morphometric and mechanical comparison of the structural elements of byssus from Mytilus edulis and Mytilus galloprovincialis.

    Science.gov (United States)

    Lucas, Jared M; Vaccaro, Eleonora; Waite, J Herbert

    2002-06-01

    Marine mussels are renowned for their ability to produce an extra-organismic tendon-like structure that can withstand the wave forces associated with the intertidal habitat. Initial characterization of byssal properties has focused on Mytilus edulis, with few detailed comparisons with other mussels. M. galloprovincialis, a closely related species, provides an opportunity for a thorough comparison. Three full-length cDNA clones encoding the byssal collagens, precollagen D (preCol-D), preCol-NG and preCol-P, were isolated from M. galloprovincialis. Comparisons with M. edulis preCol-D, preCol-NG and preCol-P reveal a 91.3 %, 88.6 % and 90.1 % identity with the cDNA and an 89.0 %, 88.1 % and 89.0 % identity with the deduced protein sequences, respectively. Key elements are maintained between the species: in particular, modeled bends in the collagen helix due to breaks in the Gly-X-Y pattern and the location of cysteine and putative 3,4-dihydroxyphenylalanine (DOPA) residues. A potentially important difference between the two is that, in all cases, M. galloprovincialis byssal collagens contain additional histidine residues in their flanking domains. The significance of this may lie in the ability of M. galloprovincialis to utilize more metal chelate cross-links, which have been implicated in byssal thread stability. M. edulis threads are typically twice the length and diameter of M. galloprovincialis threads and appear to contain nearly 10 % more collagen. These differences are maintained even when the different thread portions are compared. Despite differences in a number of parameters, most notably that whole M. galloprovincialis threads are stiffer, threads whether whole or separated into proximal and distal portions, have similar mechanical behaviors. It is apparent from this comparison that M. galloprovincialis and M. edulis are seemingly interchangeable models for byssal research.

  7. Intersex in Littorina littorea and DNA damage in Mytilus edulis as indicators of harbour pollution.

    Science.gov (United States)

    Rank, Jette

    2009-05-01

    Intersex in snails (Littorina littorea) and DNA damage in blue mussels (Mytilus edulis) were analysed to assess how these bio-indicators reflected the level of chemical contamination at two sites in a highly contaminated harbour in Denmark. The comet assay using mussel gill cells was an indicator of exposure to genotoxic chemicals, and the intersex index (ISI) observed in snails was an indicator of exposure to butyltin (BT) compounds. Biota and sediments were analysed for heavy metals (Cd, Cu, Pb and Zn), butyltin compounds (TBT, DBT and MBT), nine PCB congeners and 19 PAH compounds. The biological effects were found to reflect the levels of the chemicals, and it was concluded that intersex in L. littorea and DNA damage in M. edulis can be used as bio-indicators of harbour pollution.

  8. Field data and growth model for mussels Mytilus edulis in Danish waters

    DEFF Research Database (Denmark)

    Riisgard, Hans Ulrik; Lundgreen, Kim; Larsen, Poul S.

    2012-01-01

    bioenergetic growth model for mussels (μ = aWb, a = 0.871 x C - 0.986, b = -0.34), and observed power-law relations of growth data were in good agreement with the model, which takes into account the prevailing average chlorophyll a (chl a) concentration (C, μ g chl a l-1) at field sites. Thus, the b......Growth rates of blue mussels, Mytilus edulis, in suspended net-bags were measured in field experiments conducted in Limfjorden and Great Belt, Denmark, for extended periods of time (22 69 days) with up to 8 intermediate data samplings during the period. The resulting time series of growth...

  9. Evidence of Anti-Proliferative Activities in Blue Mussel (Mytilus edulis By-Products

    Directory of Open Access Journals (Sweden)

    Marie-Elise Carbonneau

    2013-03-01

    Full Text Available Shellfish waste components contain significant levels of high quality protein and are therefore a potential source for biofunctional high-value peptides. The feasibility of applying a pilot scale enzymatic hydrolysis process to whole Mytilus edulis and, by fractionation, recover hydrolysates presenting a biological activity of interest, was evaluated. Fractions were tested on four immortalized cancerous cell lines: A549, BT549, HCT15 and PC3. The 50 kDa fraction, enriched in peptides, presented anti-proliferative activity with all cell lines and results suggest a bioactive molecule synergy within the fraction. At a protein concentration of 44 µg/mL, the 50 kDa fraction induced a mortality of 90% for PC3, 89% for A549, 85% for HCT15 and of 81% for BT549 cell lines. At the low protein concentration of only 11 µg/mL the 50 kDa fraction still entails a cell mortality of 76% for A549 and 87% for PC3 cell lines. The 50 kDa fraction contains 56% of proteins, 3% of lipids and 6% of minerals on a dry weight basis and the lowest levels detected of taurine and methionine and highest levels of threonine, proline and glycine amino acids. The enzymatic hydrolysis process suggests that Mytilus edulis by-products should be viewed as high-valued products with strong potential as anti-proliferative agent and promising active ingredients in functional foods.

  10. Immune modulation in the blue mussel Mytilus edulis exposed to North Sea produced water

    Energy Technology Data Exchange (ETDEWEB)

    Hannam, M.L., E-mail: marie.hannam@plymouth.ac.u [Ecotoxicology and Stress Biology Research Centre, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, PL4 8AA (United Kingdom); Bamber, S.D.; Sundt, R.C. [IRIS - Biomiljo, Mekjarvik 12, 4070 Randaberg (Norway); Galloway, T.S. [School of Biosciences, University of Exeter, Hatherly Laboratories, Prince of Wales Road, Exeter, EX4 4PS (United Kingdom)

    2009-06-15

    The discharge of oil well produced water (PW) provides a constant source of contaminants to the marine environment including polycyclic aromatic hydrocarbons, alkylated phenols, metals and production chemicals. High concentrations of PW cause adverse effects to exposed biota, including reduced survival, growth and reproduction. Here we explore the effects of PW on immune function in the blue mussel, Mytilus edulis. Mussels were exposed for 21 days to sublethal PW concentrations (0.125-0.5%) and cellular parameters were measured. Cell viability, phagocytosis and cytotoxicity were inhibited after exposure to 0.25% and 0.5% PW, whilst the 0.125% PW treatment produced significant increases in these biomarker responses. This biphasic response was only observed after 7 days exposure; longer exposure periods led to a reduction in immune parameters. Results indicate that PW concentrations close to the discharge point cause modulation to cellular immunity. The implications for longer-term disease resistance are discussed. - Exposure to produced water alters immune function in the sentinel species Mytilus edulis.

  11. Adaptation to anaerobic metabolism in two mussel species, Mytilus edulis and Mytilus galloprovincialis, from the tidal zone at Arcachon Bay, France

    Science.gov (United States)

    de Vooys, C. G. N.

    Aspects of anaerobic metabolism were investigated in two sympatric mussel species, viz. Mytilus edulis and Mytilus galloprovincialis, living in the tidal zone in Arcachon Bay, France. Specific activities of pyruvate kinase (PK) and phosphoenolpyruvate kinase (PEP-CK) were remarkably similar in the two sympatric species and generally corresponded more closely to those observed in M. galloprovincialis in the Mediterranean than with M. edulis in the Dutch Wadden Sea. However, the values for the radio PK: PEP-CK for the two species in Arcachon Bay agreed with those of intertidal M. edulis from the Dutch Wadden Sea. Succinate accumulation during the first 24 h of anaerobicsis was about the same as in M. galloprovincialis in the Mediterranean, but decreased during the second 24 h, particularly in M. edulis, obviously due to propionate formation. Decrease in ATP concentrations in the tissues during anaerobiosis corresponded to that of intertidal M. edulis from the Dutch Wadden Sea. With the exception of specific activities of PK and PEP-CK, all properties investigated in both species were as expected in intertidal mussels.

  12. Oxygen isotope ratios in the shell of Mytilus edulis: archives of glacier meltwater in Greenland?

    Science.gov (United States)

    Versteegh, E. A. A.; Blicher, M. E.; Mortensen, J.; Rysgaard, S.; Als, T. D.; Wanamaker, A. D., Jr.

    2012-09-01

    Melting of the Greenland Ice Sheet (GrIS) is accelerating and will contribute significantly to global sea level rise during the 21st century. Instrumental data on GrIS melting only cover the last few decades, and proxy data extending our knowledge into the past are vital for validating models predicting the influence of ongoing climate change. We investigated a potential meltwater proxy in Godthåbsfjord (West Greenland), where glacier meltwater causes seasonal excursions with lower oxygen isotope water (δ18Ow) values and salinity. The blue mussel (Mytilus edulis) potentially records these variations, because it precipitates its shell calcite in oxygen isotopic equilibrium with ambient seawater. As M. edulis shells are known to occur in raised shorelines and kitchen middens from previous Holocene warm periods, this species may be ideal in reconstructing past meltwater dynamics. We investigate its potential as a palaeo-meltwater proxy. First, we confirmed that M. edulis shell calcite oxygen isotope (δ18Oc) values are in equilibrium with ambient water and generally reflect meltwater conditions. Subsequently we investigated if this species recorded the full range of δ18Ow values occurring during the years 2007 to 2010. Results show that δ18Ow values were not recorded at very low salinities (future research will expand on the geographical and temporal range of the shell measurements by sampling mussels in other fjords in Greenland along a south-north gradient, and by sampling shells from raised shorelines and kitchen middens from prehistoric settlements in Greenland.

  13. Oxygen isotope ratios in the shell of Mytilus edulis: archives of glacier meltwater in Greenland?

    Directory of Open Access Journals (Sweden)

    T. D. Als

    2012-09-01

    Full Text Available Melting of the Greenland Ice Sheet (GrIS is accelerating and will contribute significantly to global sea level rise during the 21st century. Instrumental data on GrIS melting only cover the last few decades, and proxy data extending our knowledge into the past are vital for validating models predicting the influence of ongoing climate change. We investigated a potential meltwater proxy in Godthåbsfjord (West Greenland, where glacier meltwater causes seasonal excursions with lower oxygen isotope water (δ18Ow values and salinity. The blue mussel (Mytilus edulis potentially records these variations, because it precipitates its shell calcite in oxygen isotopic equilibrium with ambient seawater. As M. edulis shells are known to occur in raised shorelines and kitchen middens from previous Holocene warm periods, this species may be ideal in reconstructing past meltwater dynamics. We investigate its potential as a palaeo-meltwater proxy. First, we confirmed that M. edulis shell calcite oxygen isotope (δ18Oc values are in equilibrium with ambient water and generally reflect meltwater conditions. Subsequently we investigated if this species recorded the full range of δ18Ow values occurring during the years 2007 to 2010. Results show that δ18Ow values were not recorded at very low salinities (M. edulis δ18Oc values are suitable in reconstructing past meltwater amounts in most cases, but care has to be taken that shells are collected not too close to a glacier, but rather in the mid region or mouth of the fjord. The focus of future research will expand on the geographical and temporal range of the shell measurements by sampling mussels in other fjords in Greenland along a south-north gradient, and by sampling shells from raised shorelines and kitchen middens from prehistoric settlements in Greenland.

  14. Paramyosin structures in the thick filaments of the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Heumann, H G

    1980-10-01

    Freeze-substituted cells of the anterior byssus retractor muscle of Mytilus edulis contain paramyosin filaments which exhibit a characteristic fine structure. Longitudinally sectioned filaments show a variety of band patterns, those occurring most frequently being cross, oblique or double oblique striations. The periodic spacings within one pattern are precise as can be demonstrated by Markham analysis and optical diffractometry. The patterns arise from structures in the interior of the filament since they persist in serially sectioned filaments and a layered structure is visible in cross-sectioned filaments. The different patterns are found to be convertible by rotating the grid around the filament axis. The observations led to the conclusion that the paramyosin core has some kind of helical arrangement. A model is proposed which consists of concentric layers of parallel paramyosin molecules which are displaced along the molecular axis in such a way that the characteristic Bear-Selby net structure results.

  15. The impact of the adult blue mussel (Mytilus edulis) population on settling of conspecific larvae

    DEFF Research Database (Denmark)

    Dolmer, Per; Stenalt, Ea

    2010-01-01

    -settling mortality may be due to a reduced benthic predation in habitats with high complexity. In a field experiment, the larval settling of blue mussels, Mytilus edulis, was recorded on an artificial substrate 0.25, 1 and 2 m above the bottom during six periods in spring 1999. The experiment was conducted at four....... A size analysis of the settled mussels indicated that the reduction in settling intensity close to mussel beds was due to a pre-settling process: the larvae were predated by the filtering adult mussels. Settling was significantly affected by wind stress. During periods with a high mean wind velocity...... and a turbulent water column, the larvae showed a reduced settlement 1 m above a mussel bed relative to 2 m above, whereas the same patterns not could be observed outside a mussel bed. The importance of the filtration activity of the adult mussels and the behaviour of the larvae is discussed. The recruitment...

  16. The influence of climatic and physiological performance on population dynamics of Mytilus edulis in West Greenland

    DEFF Research Database (Denmark)

    Thyrring, Jakob; Blicher, Martin; Sejr, Mikael Kristian

    2014-01-01

    . Results show an overall decline in blue mussel abundance along the coast from south to north Greenland. Physiological adaptation and plasticity of blue mussels was found across latitudes spanning from the temperate to the High Arctic region. Combined our results indicate that low ocean temperature per se....... The blue mussel (Mytilus edulis) has recently expanded its northern distribution in Greenland and is considered to be a sensitive indicator of climate changes. Blue mussels could be a species that would respond to a warmer climate by increased abundance and growth rates in the Arctic. However, adequate...... data on current distribution and physiological performance of blue mussels in the Arctic is lacking, and knowledge of how “climate” in a broad sense specifically influence population dynamics of this species is unknown. Here, we present data on abundance, age and mortality of blue mussels in West...

  17. Modulations in cell-mediated immunity of Mytilus edulis following the `Sea Empress` oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Dyrynda, E.A.; Dyrynda, P.E.J.; Ratcliffe, N.A. [University of Wales Swansea (United Kingdom). School of Biological Sciences; Law, R.J.; Kelly, C.A.; Graham, K.L. [MAFF Fisheries Lab., Burnham-on-Crouch (United Kingdom); Pipe, R.K. [Plymouth Marine Lab. (United Kingdom)

    1997-02-01

    The `Sea Empress` oil tanker grounded outside Milford Haven (Wales, UK) in February 1996, spilling {approx} 70,000 tonnes of crude oil and contaminating over 100 km of coastline, causing mass mortalities and strandings of at least 11 mollusc species. Intensive field monitoring commenced after the spill, examining immunity and hydrocarbon levels in the mussel, Mytilus edulis (Mollusca: Bivalvia), a commercially-harvested species which can accumulate contaminants. Comparisons of mussels from oiled and reference sites revealed significant modulations in cell-mediated immunity. Elevations in blood cell (haemocyte) numbers and decreases in superoxide generation and phagocytosis were identified in contaminated animals. The immune response of contaminated mussels gradually improved and generally showed no significant differences compared with clean mussels after 11 weeks. By then, total hydrocarbon content in contaminated mussels had declined by 70-90%, while polycyclic aromatic hydrocarbon content had decreased by over 90%. (author)

  18. Metabolism of pectenotoxins in brown crabs Cancer pagurus fed with blue mussels Mytilus edulis

    Institute of Scientific and Technical Information of China (English)

    LI Zhaoxin

    2009-01-01

    We investigated the metabolism of pectenotoxins in brown crabs (Cancer pagurus). The crabs were fed with blue mussels (Mytilus edulis) for 21 d then depurated for 42 d. We extracted the toxins from the digestive glands of contaminated crabs, uncontaminated crabs (control group), and the meat of blue mussels using methanol. Extracts of the crab digestive glands were fractionated by liquid-liquid partitioning and solid phase extraction. The fractions were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and liquid chromatography coupled with ion-trap mass spectrometry (LC-MSn). We detected a new PTX-like compound, designated as metabolite-1. The MS2 mass spectrum of the metabolite-1 [M+Na]+ ion at m/z 897.5 revealed fragment ions at m/z 853.5 and 555.5, typical of those exhibited by other pectenotoxins.

  19. Perturbation induced changes in substrate use by the blue mussel, Mytilus edulis, in sedimentary systems

    Science.gov (United States)

    wa Kangeri, Arno K.; Jansen, Jeroen M.; Barkman, Barbara R.; Donker, Jasper J. A.; Joppe, Daniel J.; Dankers, Norbert M. J. A.

    2014-01-01

    For sessile benthic marine organisms adhesion to a stable substrate is important for survival. Sedimentary systems, however, generally lack stable surfaces. How sessile species like the mussel, Mytilus edulis, are able to achieve stability in unstable sediments is not fully understood. An intertidal mussel bed in the tidal flats in the Western portion of the Dutch Wadden Sea was selected to investigate adhesion behavior of M. edulis. Sampling was conducted along a hydrodynamic gradient along the Front-edge, Center and Back-edge of a mussel bed. Mussels along the bed edges were characterized by adhesion to fine shell debris and high numbers of byssus threads. Mussels in the center of the bed were characterized by adhesion to shells of living conspecifics and relatively low numbers of byssus threads. An experimental investigation to isolate the role of perturbation on adhesion strategies was carried out under laboratory conditions. Experimental results show that under perturbed conditions mussels developed increased numbers of byssus threads relative to mussels left unperturbed. Additionally, mussels subjected to perturbation preferentially adhered more frequently to fine shell debris while unperturbed mussels adhered more frequently to conspecifics. Results show that differentiation in adhesion strategy is driven by physical perturbation and mediated by bed density. The results also suggest that adhesion by mussels in a sedimentary environment is a selective process in which larger shell fragments and shells of conspecifics are the preferred substrate.

  20. Microplastics are taken up by mussels (Mytilus edulis) and lugworms (Arenicola marina) living in natural habitats.

    Science.gov (United States)

    Van Cauwenberghe, Lisbeth; Claessens, Michiel; Vandegehuchte, Michiel B; Janssen, Colin R

    2015-04-01

    We studied the uptake of microplastics under field conditions. At six locations along the French-Belgian-Dutch coastline we collected two species of marine invertebrates representing different feeding strategies: the blue mussel Mytilus edulis (filter feeder) and the lugworm Arenicola marina (deposit feeder). Additional laboratory experiments were performed to assess possible (adverse) effects of ingestion and translocation of microplastics on the energy metabolism (cellular energy allocation) of these species. Microplastics were present in all organisms collected in the field: on average 0.2 ± 0.3 microplastics g(-1) (M. edulis) and 1.2 ± 2.8 particles g(-1) (A. marina). In a proof of principle laboratory experiment, mussels and lugworms exposed to high concentrations of polystyrene microspheres (110 particles mL(-1) seawater and 110 particles g(-1) sediment, respectively) showed no significant adverse effect on the organisms' overall energy budget. The results are discussed in the context of possible risks as a result of the possible transfer of adsorbed contaminants.

  1. Mass spectrometry data from a quantitative analysis of protein expression in gills of immuno-challenged blue mussels (Mytilus edulis).

    Science.gov (United States)

    Hörnaeus, K; Guillemant, J; Mi, J; Hernroth, B; Bergquist, J; Lind, S Bergström

    2016-09-01

    Here, we provide the dataset associated with our research article on the potential effects of ocean acidification on antimicrobial peptide (AMP) activity in the gills of Mytilus edulis, "Impact of ocean acidification on antimicrobial activity in gills of the blue mussel (Mytilus edulis)" [1]. Blue mussels were stimulated with lipopolysaccharides and samples were collected at different time points post injection. Protein extracts were prepared from the gills, digested using trypsin and a full in-depth proteome investigation was performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Protein identification and quantification was performed using the MaxQuant 1.5.1.2 software, "MaxQuant enables high peptide identification rates, individualized p.p.b.-range mass accuracies and proteome-wide protein quantification" [2].

  2. On the dynamics of the stocks of blue mussels ( Mytilus edulis L.) in the Danish Wadden Sea

    DEFF Research Database (Denmark)

    Munch-Petersen, Sten; Kristensen, Per Sand

    2001-01-01

    As biological basis for the monitoring programme for the commercially exploited stock(s) of mussels (Mytilus edulis L.) in the Danish Wadden Sea, samples of mussels have been collected regularly since 1986, both from sub-tidal and inter- tidal mussel beds. These samples are the basis for the esti...... with figures from other investigations. These analyses have been the basis for annual assessments of the mussel stocks, which again are used in the current management of mussel fishery in the Danish Wadden Sea.......As biological basis for the monitoring programme for the commercially exploited stock(s) of mussels (Mytilus edulis L.) in the Danish Wadden Sea, samples of mussels have been collected regularly since 1986, both from sub-tidal and inter- tidal mussel beds. These samples are the basis...

  3. The use of cholinergic biomarker, cholinesterase activity of blue mussel Mytilus edulis to detect the effects of organophosphorous pesticides

    OpenAIRE

    Yaqin, Khusnul

    2007-01-01

    The aim of the study was to investigate the effects of organophosphorous pesticide on the cholinesterase activity of different organs of Mytilus edulis. The mussels were exposed to serial dilutions of the pesticides (0, 50, 100, 200, 500, and 1000 ??g/l) for 96 h. A significant inhibition of the cholinesterase activity from gill occurred at the lowest concentration, which indicated that gill was the most sensitive organ. The moderate sensitive organs were foot and mantle, which we...

  4. Investigations of the capacity of synthesizing 3β-sterols in mollusca—XIII. Biosynthesis and composition of sterols in some bivalves (Anisomyaria)

    NARCIS (Netherlands)

    Voogt, P.A.

    1975-01-01

    1. The incorporation of sodium acetate-1- or -2-¹⁴C into some lipid classes of the anisomyarian bivalves Mytilus edulis, Atrina fragilis and Ostrea edulis was investigated. 2. It was demonstrated that the acetate was utilized for the biosynthesis of both saponifiable and non-saponifiable lipids. 3.

  5. Distribution and relationships of trace metals in soft tissue, byssus and shells of Mytilus edulis trossulus from the southern Baltic

    Energy Technology Data Exchange (ETDEWEB)

    Szefer, P.; Frelek, K.; Szefer, K.; Lee, C.-B.; Kim, B.-S.; Warzocha, J.; Zdrojewska, I.; Ciesielski, T

    2002-12-01

    Soft tissues and byssus of the blue mussel (Mytilus edulis) were better metal bioindicators than shells. - Concentrations of Hg, Cd, Pb, Ag, Cu, Zn, Cr, Ni, Co, Mn, and Fe in soft tissues, shells and byssus of blue mussel (Mytilus edulis trossulus) from 23 sites along the Polish coast of the Baltic Sea were determined by AAS method. Byssus, as compared with the soft tissue, concentrated more effectively Pb, Cu, Cr, and especially Ag, Ni, Mn and Fe, moderately Hg and Zn and less effectively Cd. Significant inter-regional and inter-size differences in metal concentrations in both soft tissues and byssus were recorded. Highly significant correlations (P<0.01, P<0.05) were observed between tissue and byssal concentrations of Cd, Pb, Ni and Ag. Factor analysis showed clear separation of both the tissue and byssi samples based on their geographic distribution, possibly reflecting a different rate of deposition of clay minerals at the head of the Pomeranian Bay and the Gulf of Gdansk. The Pomeranian Bay differs from the Gulf of Gdansk in respect to geological structure of bottom sediments as a substrata for the M. edulis trossulus as well as in relation to various sources of metallic pollutants. From the data obtained in the present study and those reported previously the soft tissue and especially byssus of M. edulis, in contrast to shells, appear to be a significantly better bioindicator for identification of coastal areas exposed to metallic contaminants.

  6. Towards the determination of Mytilus edulis food preferences using the dynamic energy budget (DEB) theory.

    Science.gov (United States)

    Picoche, Coralie; Le Gendre, Romain; Flye-Sainte-Marie, Jonathan; Françoise, Sylvaine; Maheux, Frank; Simon, Benjamin; Gangnery, Aline

    2014-01-01

    The blue mussel, Mytilus edulis, is a commercially important species, with production based on both fisheries and aquaculture. Dynamic Energy Budget (DEB) models have been extensively applied to study its energetics but such applications require a deep understanding of its nutrition, from filtration to assimilation. Being filter feeders, mussels show multiple responses to temporal fluctuations in their food and environment, raising questions that can be investigated by modeling. To provide a better insight into mussel-environment interactions, an experiment was conducted in one of the main French growing zones (Utah Beach, Normandy). Mussel growth was monitored monthly for 18 months, with a large number of environmental descriptors measured in parallel. Food proxies such as chlorophyll a, particulate organic carbon and phytoplankton were also sampled, in addition to non-nutritious particles. High-frequency physical data recording (e.g., water temperature, immersion duration) completed the habitat description. Measures revealed an increase in dry flesh mass during the first year, followed by a high mass loss, which could not be completely explained by the DEB model using raw external signals. We propose two methods that reconstruct food from shell length and dry flesh mass variations. The former depends on the inversion of the growth equation while the latter is based on iterative simulations. Assemblages of food proxies are then related to reconstructed food input, with a special focus on plankton species. A characteristic contribution is attributed to these sources to estimate nutritional values for mussels. M. edulis shows no preference between most plankton life history traits. Selection is based on the size of the ingested particles, which is modified by the volume and social behavior of plankton species. This finding reveals the importance of diet diversity and both passive and active selections, and confirms the need to adjust DEB models to different

  7. Impact of ocean acidification on antimicrobial activity in gills of the blue mussel (Mytilus edulis).

    Science.gov (United States)

    Hernroth, B; Baden, S; Tassidis, H; Hörnaeus, K; Guillemant, J; Bergström Lind, S; Bergquist, J

    2016-08-01

    Here, we aimed to investigate potential effects of ocean acidification on antimicrobial peptide (AMP) activity in the gills of Mytilus edulis, as gills are directly facing seawater and the changing pH (predicted to be reduced from ∼8.1 to ∼7.7 by 2100). The AMP activity of gill and haemocyte extracts was compared at pH 6.0, 7.7 and 8.1, with a radial diffusion assay against Escherichia coli. The activity of the gill extracts was not affected by pH, while it was significantly reduced with increasing pH in the haemocyte extracts. Gill extracts were also tested against different species of Vibrio (V. parahaemolyticus, V. tubiashii, V. splendidus, V. alginolyticus) at pH 7.7 and 8.1. The metabolic activity of the bacteria decreased by ∼65-90%, depending on species of bacteria, but was, as in the radial diffusion assay, not affected by pH. The results indicated that AMPs from gills are efficient in a broad pH-range. However, when mussels were pre-exposed for pH 7.7 for four month the gill extracts presented significantly lower inhibit of bacterial growth. A full in-depth proteome investigation of gill extracts, using LC-Orbitrap MS/MS technique, showed that among previously described AMPs from haemocytes of Mytilus, myticin A was found up-regulated in response to lipopolysaccharide, 3 h post injection. Sporadic occurrence of other immune related peptides/proteins also pointed to a rapid response (0.5-3 h p.i.). Altogether, our results indicate that the gills of blue mussels constitute an important first line defence adapted to act at the pH of seawater. The antimicrobial activity of the gills is however modulated when mussels are under the pressure of ocean acidification, which may give future advantages for invading pathogens.

  8. Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia shell calcite precipitated at constant temperature

    Directory of Open Access Journals (Sweden)

    P. S. Freitas

    2009-07-01

    Full Text Available Small-scale heterogeneity of biogenic carbonate elemental composition can be a significant source of error in the accurate use of element/Ca ratios as geochemical proxies. In this study ion microprobe (SIMS profiles showed significant small-scale variability of Mg/Ca, Sr/Ca and Mn/Ca ratios in new shell calcite of the marine bivalves Pecten maximus and Mytilus edulis that was precipitated during a constant-temperature culturing experiment. Elevated Mg/Ca, Sr/Ca and Mn/Ca ratios were found to be associated with the deposition of elaborate shell features, i.e. a shell surface stria in P. maximus and surface shell disturbance marks in both species, the latter a common occurrence in bivalve shells. In both species the observed small-scale elemental heterogeneity most likely was not controlled by variable transport of ions to the extra-pallial fluid, but by factors such as the influence of shell organic content and/or crystal size and orientation, the latter reflecting conditions at the shell crystal-solution interface. In the mid and innermost regions of the P. maximus shell the lack of significant small-scale variation of Mg/Ca ratios, which is consistent with growth at constant temperature, suggest a potential application as a palaeotemperature proxy. Cross-growth band element/Ca ratio profiles in the interior of bivalve shells may provide more promising palaeo-environmental tools than sampling from the outer region of bivalve shells.

  9. Contaminant effects on growth, age-structure, and reproduction, of Mytilus edulis from Puget Sound, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Casillas, E.; Kardong, K.; Kagley, A.; Snider, R.G.; Stein, J.E. [NOAA, Seattle, WA (United States). Environmental Conservation Division

    1994-12-31

    Age-length relationships, age structure, and reproductive status (fecundity, egg size) of Mytilus edulis from six sites in central Puget Sound and one site in the relatively pristine area of northern Puget Sound were measured. Mussels from urban-associated sites (areas with elevated sediment concentrations of PAHs, PCBs, and toxic and essential metals) exhibited high tissue burdens of these contaminants. Age length relationships, fitted to the von Bertalanffy equation, showed that the growth of mussels from urban-associated areas was similar, but was lower than in mussels from minimally-contaminated environments. Comparison of mussel population age-structure showed that at urban sites, mussels of comparable size were consistently older than mussels from minimally contaminated areas and the mean age of urban populations was higher than that of rural populations. In mussels from urban sites, gonad mass was lower while number of oocytes/g gonad was similar compared to mussels from minimally-contaminated areas of Puget Sound. Thus, in mussels from urban sites fecundity was reduced compared to mussels of comparable age from reference sites. The findings support the hypothesis that mussels from the urban areas exhibit impaired growth, altered population age-structure, and reproductive impairment as a result of accumulation of chemical contaminants.

  10. Mussel (Mytilus edulis) byssus deposition in response to variations in surface wettability.

    Science.gov (United States)

    Aldred, N; Ista, L K; Callow, M E; Callow, J A; Lopez, G P; Clare, A S

    2006-02-22

    Mussels (Mytilus edulis) are economically important in their role as an aquaculture species and also with regard to marine biofouling. They attach tenaciously to a wide variety of submerged surfaces by virtue of collagenous attachment threads termed 'byssi'. The aim of this study was to characterize the spreading of the byssal attachment plaque, which mediates attachment to the surface, on a range of surfaces in response to changes in wettability. To achieve this, well characterized self-assembled monolayers of omega-terminated alkanethiolates on gold were used, allowing correlation of byssal plaque spreading with a single surface characteristic--wettability. The present results were inconsistent with those from previous studies, in that there was a positive correlation between plaque size and surface wettability; a trend which is not explained by conventional wetting theory for a three-phase system. A recent extension to wetting theory with regard to hydrophilic proteins is discussed and the results of settlement assays are used to attempt reconciliation of these results with those of similar previous studies and, also, with recent data presented for the spreading of Ulva linza spore adhesive.

  11. Differential depuration of poliovirus, Escherichia coli, and a coliphage by the common mussel, Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Power, U.F.; Collins, J.K. (Univ. College, Cork (Ireland))

    1989-06-01

    The elimination of sewage effluent-associated poliovirus, Escherichia coli, and a 22-nm icosahedral coliphage by the common mussel, Mytilus edulis, was studied. Both laboratory-and commercial-scale recirculating, UV depuration systems were used in this study. In the laboratory system, the logarithms of the poliovirus, E. coli, and coliphage levels were reduced by 1.86, 2.9, and 2.16, respectively, within 52 h of depuration. The relative patterns and rates of elimination of the three organisms suggest that they are eliminated from mussels by different mechanisms during depuration under suitable conditions. Poliovirus was not included in experiments undertaken in the commercial-scale depuration system. The differences in the relative rates and patterns of elimination were maintained for E. coli and coliphage in this system, with the logarithm of the E. coli levels being reduced by 3.18 and the logarithm of the coliphage levels being reduced by 0.87. The results from both depuration systems suggest that E. coli is an inappropriate indicator of the efficiency of virus elimination during depuration. The coliphage used appears to be a more representative indicator. Depuration under stressful conditions appeared to have a negligible affect on poliovirus and coliphage elimination rates from mussels. However, the rate and pattern of E. coli elimination were dramatically affected by these conditions. Therefore, monitoring E. coli counts might prove useful in ensuring that mussels are functioning well during depuration.

  12. Feeding activity of mussels Mytilus edulis related to near-bed currents and phytoplankton biomass

    DEFF Research Database (Denmark)

    Dolmer, Per

    2000-01-01

    The feeding activity of blue mussels Mytilus edulis was investigated in the field and related to near-bottom current velocities and the phytoplankton biomass in the near-bottom water layers for four days. The body content of Chl-a in mussels and their shell gap size were used as indices...... of filtration activity. During days 1 and 2 the near-bed current velocities were low (1.2-2.1 cm s(-1)), and the near-bed phytoplankton biomass was at the same time lower than near the water surface. Between 44 and 69% of the mussels had closed shells and accumulated only small amounts of Chl-a in the body...... rates were estimated from the density of active mussels times the estimated filtration rates (based on the gap size of the mussels and literature values for corresponding filtration rates). Actual population filtration rates ranged from 6.4 to 22.8 m(3) m(-2) d(-1) on days 1 and 3, respectively...

  13. Buried Alive: The Behavioural Response of the Mussels, Modiolus modiolus and Mytilus edulis to Sudden Burial by Sediment.

    Directory of Open Access Journals (Sweden)

    Zoë L Hutchison

    Full Text Available Sedimentation in the sea occurs through natural processes, such as wave and tidal action, which can be exacerbated during storms and floods. Changes in terrestrial land use, marine aggregate extraction, dredging, drilling and mining are known to result in substantial sediment deposition. Research suggests that deposition will also occur due to the modern development of marine renewable energy. The response to individual burial under three depths of sediment, three sediment fractions and five burial durations was investigated in two mussel species, Modiolus modiolus and Mytilus edulis in specialist mesocosms. Both mussel species showed substantial mortality, which increased with duration of burial and burial by finer sediment fractions. M. modiolus was better able to survive short periods of burial than M. edulis, but at longer durations mortality was more pronounced. No mortality was observed in M. modiolus in burial durations of eight days or less but by 16 days of burial, over 50% cumulative mortality occurred. Under variable temperature regimes, M. edulis mortality increased from 20% at 8°C to over 60% at 14.5 and 20°C. Only M. edulis was able to emerge from burial, facilitated by increased byssus production, laid mostly on vertical surfaces but also on sediment particles. Emergence was higher from coarse sediment and shallow burials. Byssus production in M. edulis was not related to the condition index of the mussels. Results suggest that even marginal burial would result in mortality and be more pronounced in warm summer periods. Our results suggest that in the event of burial, adult M. modiolus would not be able to emerge from burial unless local hydrodynamics assist, whereas a small proportion of M. edulis may regain contact with the sediment water interface. The physiological stress resulting in mortality, contribution of local hydrodynamics to survival and other ecological pressures such as mussels existing in aggregations, are

  14. Buried Alive: The Behavioural Response of the Mussels, Modiolus modiolus and Mytilus edulis to Sudden Burial by Sediment.

    Science.gov (United States)

    Hutchison, Zoë L; Hendrick, Vicki J; Burrows, Michael T; Wilson, Ben; Last, Kim S

    2016-01-01

    Sedimentation in the sea occurs through natural processes, such as wave and tidal action, which can be exacerbated during storms and floods. Changes in terrestrial land use, marine aggregate extraction, dredging, drilling and mining are known to result in substantial sediment deposition. Research suggests that deposition will also occur due to the modern development of marine renewable energy. The response to individual burial under three depths of sediment, three sediment fractions and five burial durations was investigated in two mussel species, Modiolus modiolus and Mytilus edulis in specialist mesocosms. Both mussel species showed substantial mortality, which increased with duration of burial and burial by finer sediment fractions. M. modiolus was better able to survive short periods of burial than M. edulis, but at longer durations mortality was more pronounced. No mortality was observed in M. modiolus in burial durations of eight days or less but by 16 days of burial, over 50% cumulative mortality occurred. Under variable temperature regimes, M. edulis mortality increased from 20% at 8°C to over 60% at 14.5 and 20°C. Only M. edulis was able to emerge from burial, facilitated by increased byssus production, laid mostly on vertical surfaces but also on sediment particles. Emergence was higher from coarse sediment and shallow burials. Byssus production in M. edulis was not related to the condition index of the mussels. Results suggest that even marginal burial would result in mortality and be more pronounced in warm summer periods. Our results suggest that in the event of burial, adult M. modiolus would not be able to emerge from burial unless local hydrodynamics assist, whereas a small proportion of M. edulis may regain contact with the sediment water interface. The physiological stress resulting in mortality, contribution of local hydrodynamics to survival and other ecological pressures such as mussels existing in aggregations, are discussed.

  15. Distribution and relationships of trace metals in soft tissue, byssus and shells of Mytilus edulis trossulus from the southern Baltic.

    Science.gov (United States)

    Szefe, P; Frelek, K; Szefer, K; Lee, Ch B; Kim, B S; Warzocha, J; Zdrojewska, I; Ciesielski, T

    2002-01-01

    Concentrations of Hg, Cd, Pb, Ag, Cu, Zn, Cr, Ni, Co, Mn, and Fe in soft tissues, shells and byssus of blue mussel (Mytilus edulis trossulus) from 23 sites along the Polish coast of the Baltic Sea were determined by AAS method. Byssus, as compared with the soft tissue, concentrated more effectively Pb, Cu, Cr, and especially Ag, Ni, Mn and Fe, moderately Hg and Zn and less effectively Cd. Significant inter-regional and inter-size differences in metal concentrations in both soft tissues and byssus were recorded. Highly significant correlations (Pbyssus of M. edulis, in contrast to shells, appear to be a significantly better bioindicator for identification of coastal areas exposed to metallic contaminants.

  16. Metabolic cold adaptation and aerobic performance of blue mussels (Mytilus edulis) along a temperature gradient into the High Arctic region

    DEFF Research Database (Denmark)

    Thyrring, Jakob; Rysgaard, Søren; Blicher, Martin;

    2015-01-01

    and plasticity of blue mussels across latitudes spanning from 56 to 77ºN. This indicates that low ocean temperature per se does not constrain metabolic activity of Mytilus in the Arctic; rather, we speculate that maturation of reproductive tissues, larval supply and annual energy budgets are the most relevant......The blue mussel (Mytilus edulis) has recently expanded its northern distribution in the Arctic and is therefore considered to be a sensitive indicator of climate changes in this region. In this study, we compared aerobic performance of blue mussels from High Arctic, Subarctic and temperate...... populations at different temperatures. Standard metabolic rates (SMR) and active metabolic rates (AMR) were measured for each population, and absolute (AMR − SMR) and factorial (AMR/SMR) scopes were calculated. Blue mussels from the temperate population had the lowest Q10 (= 1.8) and the largest thermal...

  17. Ileal digestibility of amino acids in novel organic protein feedstuffs for pigs: Mussel meal(Mytilus edulis)

    OpenAIRE

    Kortelainen, Tiina; Siljander-Rasi, Hilkka; Tuori, Mikko; Partanen, Kirsi

    2014-01-01

    Abstract The objective of this study was to determine the apparent total tract digestibility (ATTD) of nu-trients and the standardised ileal digestibility (SID) of amino acids in organically produced mus-sel (Mytilus edulis) meal in growing piglets. The use of mussel meal in pig feeding is not allowed for the time being, but feed legislation in the EU concerning the use of mussel meal for pigs is in progress. The experiment was carried out with a total of 24 growing pigs, 13 gilts and ...

  18. Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor; Hansen, Per Juel; Krock, Bernd

    2016-01-01

    . This is the first study to construct a full mass balance of DSP toxins during both accumulation and depuration, and we demonstrate rapid toxin accumulation in mussels at realistic in situ levels of Dinophysis. Applying the observed accumulation and depuration kinetics, we model mussel toxicity, and demonstrate...... and depuration kinetics in mussels. We mass-cultured Dinophysis acuta containing OA, DTX-1b and PTX-2 and fed it to the blue mussel, Mytilus edulis under controlled laboratory conditions for a week to study toxin accumulation and transformation. Contents of OA and DTX-1b in mussels increased linearly...

  19. Proteomic Profiling of Cytosolic Glutathione Transferases from Three Bivalve Species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea

    Directory of Open Access Journals (Sweden)

    José Carlos Martins

    2014-01-01

    Full Text Available Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs, in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  20. Proteomic profiling of cytosolic glutathione transferases from three bivalve species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea.

    Science.gov (United States)

    Martins, José Carlos; Campos, Alexandre; Osório, Hugo; da Fonseca, Rute; Vasconcelos, Vítor

    2014-01-27

    Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs), in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST) were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties) between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  1. Immunomodulating effects of environmentally realistic copper concentrations in Mytilus edulis adapted to naturally low salinities.

    Science.gov (United States)

    Höher, Nicole; Regoli, Francesco; Dissanayake, Awantha; Nagel, Matthias; Kriews, Michael; Köhler, Angela; Broeg, Katja

    2013-09-15

    The monitoring of organisms' health conditions by the assessment of their immunocompetence may serve as an important criterion for the achievement of the Good Environmental Status (GES) as defined in the Marine Strategy Framework Directive (EU). In this context, the complex role of natural environmental stressors, e.g. salinity, and interfering or superimposing effects of anthropogenic chemicals, should be carefully considered, especially in scenarios of low to moderate contamination. Organisms from the Baltic Sea have adapted to the ambient salinity regime, however energetically costly osmoregulating processes may have an impact on the capability to respond to additional stress such as contamination. The assessment of multiple stressors, encompassing natural and anthropogenic factors, influencing an organisms' health was the main aim of the present study. Immune responses of Mytilus edulis, collected and kept at natural salinities of 12‰ (LS) and 20‰ (MS), respectively, were compared after short-term exposure (1, 7 and 13 days) to low copper concentrations (5, 9 and 16 μg/L Cu). A significant interaction of salinity and copper exposure was observed in copper accumulation. LS mussels accumulated markedly more copper than MS mussels. No combined effects were detected in cellular responses. Bacterial clearance was mostly achieved by phagocytosis, as revealed by a strong positive correlation between bacterial counts and phagocytic activity, which was particularly pronounced in LS mussels. MS mussels, on the other hand, seemingly accomplished bacterial clearance by employing additional humoral factors (16 μg/L Cu). The greatest separating factor in the PCA biplot between LS and MS mussels was the proportion of granulocytes and hyalinocytes while functional parameters (phagocytic activity and bacterial clearance) were hardly affected by salinity, but rather by copper exposure. In conclusion, immune responses of the blue mussel may be suitable and sensitive

  2. Depressant effect of active shortening in the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Ekelund, M C

    1983-03-01

    The effect of shortening during activity, previously characterized in vertebrate striated muscle, was investigated in the anterior byssus retractor muscle (ABRM) of the mollusc Mytilus edulis. This muscle is considered to have an essentially myosin-linked Ca2+-regulatory system. Release steps of different amplitude were performed during isometric phasic contraction, and force redevelopment was recorded at a muscle length L1, defined as 90% of the muscle length at which a slight resting tension, approximately 1 mN, appeared in the presence of 2.5 X 10(-5) M 5-HT. Active shortening caused a graded depression of the contractile force without affecting the total duration of the mechanical response. Peak redeveloped force after muscle shortening of 0.06 L1 and 0.18 L1 was reduced by approximately 1.5% and 7.0%, respectively, of the isometric tension value at L1. The shortening effect was fully reversible, and had a lifetime of approximately 8 to 9 s. The depressant effect of active shortening was augmented at a reduced degree of activation of the muscle. The presence of caffeine and dantrolene and altered tonicity of the extracellular medium (0.9 T-1.2 T) did not significantly affect the shortening induced depression obtained at maximum phasic activation of the preparation. The nature of the shortening effect is compared to that obtained in vertebrate striated muscle and is discussed on the basis of differences in Ca2+-regulation of the contractile system in these two muscles.

  3. Exotic collagen gradients in the byssus of the mussel Mytilus edulis.

    Science.gov (United States)

    Qin, X; Waite, J H

    1995-03-01

    Byssal threads of the common mussel Mytilus edulis contain collagenous molecules from which two pepsin-resistant fragments have been isolated and characterized. These show a complementary distribution along the length of the thread, such that one predominates distally (Col-D) and the other proximally (Col-P). Both fragments contain three identical alpha-like chains with molecular masses of 50 kDa (Col-P) and 60 kDa (Col-D) and have typically collagenous amino acid compositions; for example, 35% glycine and almost 20% proline plus 4-trans-hydroxyproline. Hydroxylysine and 3-hydroxyproline were absent. Col-P sequences are also typical of collagen in consisting of tandem repeats of the triplet Gly-X-Y in which X and Y generally represent any amino acid. When proline occurs, it is hydroxylated to 4-trans-hydroxyproline only in the Y position. Seven instances where X is glycine have been detected in Col-P. Specific polyclonal anti-Col antibodies were used to isolate the precursors of Col-P and Col-D from the mussel foot. PreCol-P has a molecular mass of 95 kDa and contains 36% glycine but a lower imino acid content (13%). It has a complementary distribution with another precursor (preCol-D, 97 kDa) along the length of the foot. The two precursor compositions suggest resilin-like and silk-fibroin-like structures, respectively, in the noncollagenous domains of preCol-P and preCol-D. Immunogold labelling studies indicate that Col-P is associated with the coiled fibers of the inner core in the proximal portion of the thread, whereas Col-D is localized to the straight fiber bundles of the distal thread as well as to the outer core of the proximal thread.

  4. Concentration and depuration of some radionuclides present in a chronically exposed population of mussels (Mytilus edulis)

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, R.J.; Stevens, H.E.; Hamilton, E.I.

    1983-03-01

    Factors are described which affect the concentration (p Ci g/sup -1/ dry wt) and loss of /sup 241/ Am, /sup 239 +240/Pu, /sup 238/Pu, /sup 144/Ce, /sup 137/Cs, /sup 134/Cs, /sup 106/Ru, /sup 95/Zr and /sup 95/Nb in an exposed population of mussels Mytilus edulis L. from Ravenglass on the Esk estuary, Cumbria, UK which receives radioeffluents from the British Nuclear Fuels Ltd. (BNFL) plant at Sellafield, some 10 km to the north. Tidal position and mussel body size have a negligible influence on the concentration of /sup 241/Am, /sup 137/Cs and /sup 106/Ru in the total soft tissue, but variation in soft tissue weight throughout the year has a considerable influence on the apparent concentration and depuration times of these radionuclides. Apart from the clearance (tsub(1/2) biol, 1 to 3 h) of sediment-associated activity from the digestive tract, the depuration rate profiles follow a single component clearance curve with a biological half-life in excess of 200 d for /sup 241/ Am, /sup 239 +240/Pu, /sup 238/Pu and /sup 144/Ce, and of 40 d for /sup 137/Cs. The clearance of /sup 106/Ru is more complex and consists of a 3 component depuration profile with biological half-lives of 6 h, 12 d and 260 d. The depuration profiles presented in this work are for chronically ingested isotopes under natural conditions; acute exposure will most likely result in different profiles, especially those derived from laboratory spiking experiments. Isotope ratio data support the hypothesis that the main route of entry into the mussel for the majority of the radionuclides studied is from the water.

  5. Retention of radioactive particles and associated effects in the filter-feeding marine mollusc Mytilus edulis.

    Science.gov (United States)

    Jaeschke, B C; Lind, O C; Bradshaw, C; Salbu, B

    2015-01-01

    Radioactive particles are aggregates of radioactive atoms that may contain significant activity concentrations. They have been released into the environment from nuclear weapons tests, and from accidents and effluents associated with the nuclear fuel cycle. Aquatic filter-feeders can capture and potentially retain radioactive particles, which could then provide concentrated doses to nearby tissues. This study experimentally investigated the retention and effects of radioactive particles in the blue mussel, Mytilus edulis. Spent fuel particles originating from the Dounreay nuclear establishment, and collected in the field, comprised a U and Al alloy containing fission products such as (137)Cs and (90)Sr/(90)Y. Particles were introduced into mussels in suspension with plankton-food or through implantation in the extrapallial cavity. Of the particles introduced with food, 37% were retained for 70 h, and were found on the siphon or gills, with the notable exception of one particle that was ingested and found in the stomach. Particles not retained seemed to have been actively rejected and expelled by the mussels. The largest and most radioactive particle (estimated dose rate 3.18 ± 0.06 Gyh(-1)) induced a significant increase in Comet tail-DNA %. In one case this particle caused a large white mark (suggesting necrosis) in the mantle tissue with a simultaneous increase in micronucleus frequency observed in the haemolymph collected from the muscle, implying that non-targeted effects of radiation were induced by radiation from the retained particle. White marks found in the tissue were attributed to ionising radiation and physical irritation. The results indicate that current methods used for risk assessment, based upon the absorbed dose equivalent limit and estimating the "no-effect dose" are inadequate for radioactive particle exposures. Knowledge is lacking about the ecological implications of radioactive particles released into the environment, for example potential

  6. [Innervation of the anterior byssus retractor muscle (ABRM) in Mytilus edulis L. III. Histochemical localisation of the terminal nerves through 5-hydroxytryptamine (author's transl)].

    Science.gov (United States)

    Gilloteaux, J

    1977-04-04

    Detection of nerve structures containing 5-HT were described in the anterior byssus retractor muscle (ABRM) in Mytilus edulis L. after using the fluorescence microscope technique of Flack. We are able to confirm our previous results and assumptions given by histology and electron microscope studies: the neuromuscular "en passage" junctions, largely distributed within the ABRM, contain 5-HT.

  7. Survey of total and inorganic arsenic content in blue mussels (Mytilus edulis L.) from Norwegian fiords: Revelation of unusual high levels of inorganic arsenic

    DEFF Research Database (Denmark)

    Sloth, Jens Jørgen; Julshamn, Kåre

    2008-01-01

    The present study reports the findings of unusual high levels of inorganic arsenic in samples of blue mussels (Mytilus edulis L.). A total of 175 pooled samples of blue mussels from various locations along the Norwegian coastline were analyzed for their content of total arsenic and inorganic...

  8. Tissue-specific incorporation and genotoxicity of different forms of tritium in the marine mussel, Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Jaeschke, Benedict C., E-mail: ben@ecology.su.s [Ecotoxicology Research and Innovation Centre, School of Biomedical and Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Millward, Geoffrey E. [Consolidated Radio-isotope Facility, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Moody, A. John; Jha, Awadhesh N. [Ecotoxicology Research and Innovation Centre, School of Biomedical and Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2011-01-15

    Marine mussels (Mytilus edulis) were exposed to seawater spiked with tritiated water (HTO) at a dose rate of 122 and 79 {mu}Gy h{sup -1} for 7 and 14 days, respectively, and tritiated glycine (T-Gly) at a dose rate of 4.9 {mu}Gy h{sup -1} over 7 days. This was followed by depuration in clean seawater for 21 days. Tissues (foot, gills, digestive gland, mantle, adductor muscle and byssus) and DNA extracts from tissues were analysed for their tritium activity concentrations. All tissues demonstrated bio-accumulation of tritium from HTO and T-Gly. Tritium from T-Gly showed increased incorporation into DNA compared to HTO. About 90% of the initial activity from HTO was depurated within one day, whereas T-Gly was depurated relatively slowly, indicating that tritium may be bound with different affinities in tissues. Both forms of tritium caused a significant induction of micronuclei in the haemocytes of mussels. Our findings identify significant differential impacts on Mytilus edulis of the two chemical forms of tritium and emphasise the need for a separate classification and control of releases of tritiated compounds, to adequately protect the marine ecosystem. - Tritium from tritiated glycine demonstrates greater accumulation and persistence in tissues and enhanced genotoxicity in haemocytes of marine mussels, compared to tritium from tritiated water.

  9. CYP1A-immunopositive proteins in bivalves identified as cytoskeletal and major vault proteins

    DEFF Research Database (Denmark)

    Grøsvik, Bjørn Einar; Jonsson, Henrik; Rodríguez-Ortega, Manuel J;

    2006-01-01

    To identify possible CYP1A-immunopositive proteins in bivalves, we used anti-fish CYP1A antibodies combined with one- and two-dimensional gel electrophoresis and mass spectrometry, and found that two of the main CYP1A-immunopositive proteins in digestive gland of Mytilus edulis, were cytoskeletal...

  10. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua)-Implications for environmental monitoring in the Barents Sea

    Energy Technology Data Exchange (ETDEWEB)

    Nahrgang, J., E-mail: jasmine.m.nahrgang@uit.no [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Brooks, S.J. [Norwegian Institute for Water Research (NIVA), NO-0349 Oslo (Norway); Evenset, A. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Camus, L. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University Centre In Svalbard (UNIS), NO-9171 Longyearbyen (Norway); Jonsson, M.; Smith, T.J. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Lukina, J. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University of Tromso, Faculty of Biosciences, Fisheries and Economics, Department of Arctic and Marine Biosciences, NO-9037 Tromso (Norway); Frantzen, M. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Giarratano, E. [Centro Nacional Patagonico (CENPAT-CONICET), AR-9120 Puerto Madryn (Argentina); Renaud, P.E. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University Centre In Svalbard (UNIS), NO-9171 Longyearbyen (Norway)

    2013-02-15

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  11. Microgeographic allozyme differentiation in the hybrid zone of Mytilus galloprovincialis Lmk. and M. edulis L. on the continental European coast

    Science.gov (United States)

    Comesaña, A. S.; Sanjuan, A.

    1997-03-01

    The European Mytilus galloprovincialis Lmk. and M. edulis L. coexist and hybridize in different proportions in extended areas of the British and Atlantic French coasts. M. galloprovincialis typical allozymes seem to predominate in wave exposed areas, at high levels of attachment and in larger mussels in the British hybrid zone. Mussel samples from exposed and sheltered areas, 200 m apart, and from high and low levels of attachment were collected from a location of the French hybrid zone in 1988 92. Pure M. galloprovincialis and M. edulis populations were also taken as controls. Diagnostic enzyme loci for both Mytilus (EST-D *, LAP-1*, MPI*, ODH*) and AP-1 *, LAP-2* and PGM * loci were studied. The frequencies of the M. galloprovincialis typical alleles were significantly greater in exposed populations than in sheltered samples (e.g. 0.729 to 0.803 vs 0.192 to 0.581 for EST-D *90), and at high level of attachment than at low level for the sheltered area (e.g. 0.581 vs 0.192 for EST-D *90). Putative M. galloprovincialis was more abundant on the exposed coast (0.591 and 0.702) than on the sheltered shore, where it predominated at the high shore but not at the low shore location (0.371 vs 0.045). Significantly positive correlations between shell length and typical M. galloprovincialis compound allele frequencies were found only for populations from exposed areas. Relationships between the Mytilus genetic differentiation and ecological factors are discussed.

  12. Negative effects of blue mussel ( Mytilus edulis) presence in eelgrass ( Zostera marina) beds in Flensborg fjord, Denmark

    Science.gov (United States)

    Vinther, Hanne Fogh; Laursen, Jens Sund; Holmer, Marianne

    2008-03-01

    The effect of blue mussel ( Mytilus edulis) presence in eelgrass ( Zostera marina) beds was studied from June 2004 to July 2005 in Flensborg fjord, Denmark. The field experiments were conducted at two stations, one with only Z. marina (Eelgrass station) present and one where M. edulis were present in the Z. marina beds (Mixed station). Zostera marina parameters were measured (growth of leaves, shoot density, leaf length, and nutrient content) in combination with epiphyte cover and sediment parameters (sulphate reduction rates, sediment nutrient fluxes, organic content, C, N and P content) to examine possible positive and negative effects of the mussels on eelgrass performance. The fluxes of ammonium from the sediments were stimulated at all sampling dates at the Mixed station, and possibly stimulated epiphyte growth at this station. Further 15N signals in epiphytes from the Mixed station suggested that excretion products from the mussels were important nitrogen sources at this station. Sulphate reduction rates were enhanced at the Mixed station and also sediment sulphide concentrations increased under mussel influence, which may have resulted in sulphide toxicity and decreased growth of Z. marina at this station. The study indicates that for Z. marina beds in Flensborg Fjord the effects of M. edulis in seagrass beds are primarily negative, and raises the question whether this leads to negative effects on the stability and expansion of Z. marina beds.

  13. The respiration of the anterior byssus retractor muscle of Mytilus edulis (ABRM) after a phasic contraction.

    Science.gov (United States)

    Baguet, F; Gillis, J M

    1967-01-01

    1. The oxygen consumption of isolated anterior byssus retractor muscle of Mytilus edulis (ABRM) has been measured at rest and after phasic contractions induced by a.c. stimulation.2. The respiration was measured with a Clark oxygen electrode in successive periods of 5 or 15 min, at 20 degrees C.3. The resting respiration is 71.8 +/- 2.4 n-moles O(2)/g wet weight.min (mean +/- S.E., n = 70). It is increased by a release and decreased by a passive stretch.4. After phasic stimulation of up to 30 sec the respiration is increased and returns to a slightly higher level than the resting level in an exponential fashion with a time constant of about 10 min.5. The duration of stimulation does not change the time course of the excess respiration but it affects its magnitude. The amount of extra oxygen consumed, in n-moles O(2)/g, is made up of a constant amount, 449 +/- 102, and an amount that depends on the duration of stimulation (t, sec), which is given by t x 13.2 +/- 4.3. When due account is taken for the tension developed, these parameters become 83.1 +/- 20.7 and t x 1.24 +/- 0.66 n-moles O(2)/g muscle and kg/cm(2) of tension. This regression analysis is based on forty-eight data, with a residual error based on 5 degrees of freedom.6. Release of the tension after the last stimulus of a 30 sec tetanus reduces by half the extra oxygen consumed during the recovery whereas the same release applied 5 min later has a much smaller effect. This suggests that relaxation is an active process.7. From these measurements of the recovery metabolism the energy cost of the contraction was estimated and compared with this cost in vertebrate striated muscle. The constant item has about the same magnitude, but the item related to the duration of stimulation is about 250 times smaller.

  14. Retention of radioactive particles and associated effects in the filter-feeding marine mollusc Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Jaeschke, B.C., E-mail: Ben.Jaeschke@gmail.com [Department of Ecology Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm (Sweden); CERAD CoE, Department of Environmental Sciences, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås (Norway); Lind, O.C. [CERAD CoE, Department of Environmental Sciences, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås (Norway); Bradshaw, C. [Department of Ecology Environment and Plant Sciences, Stockholm University, SE-106 91 Stockholm (Sweden); Salbu, B. [CERAD CoE, Department of Environmental Sciences, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås (Norway)

    2015-01-01

    Radioactive particles are aggregates of radioactive atoms that may contain significant activity concentrations. They have been released into the environment from nuclear weapons tests, and from accidents and effluents associated with the nuclear fuel cycle. Aquatic filter-feeders can capture and potentially retain radioactive particles, which could then provide concentrated doses to nearby tissues. This study experimentally investigated the retention and effects of radioactive particles in the blue mussel, Mytilus edulis. Spent fuel particles originating from the Dounreay nuclear establishment, and collected in the field, comprised a U and Al alloy containing fission products such as {sup 137}Cs and {sup 90}Sr/{sup 90}Y. Particles were introduced into mussels in suspension with plankton-food or through implantation in the extrapallial cavity. Of the particles introduced with food, 37% were retained for 70 h, and were found on the siphon or gills, with the notable exception of one particle that was ingested and found in the stomach. Particles not retained seemed to have been actively rejected and expelled by the mussels. The largest and most radioactive particle (estimated dose rate 3.18 ± 0.06 Gy h{sup −1}) induced a significant increase in Comet tail-DNA %. In one case this particle caused a large white mark (suggesting necrosis) in the mantle tissue with a simultaneous increase in micronucleus frequency observed in the haemolymph collected from the muscle, implying that non-targeted effects of radiation were induced by radiation from the retained particle. White marks found in the tissue were attributed to ionising radiation and physical irritation. The results indicate that current methods used for risk assessment, based upon the absorbed dose equivalent limit and estimating the “no-effect dose” are inadequate for radioactive particle exposures. Knowledge is lacking about the ecological implications of radioactive particles released into the environment

  15. Effect of ocean acidification on the early life stages of the blue mussel Mytilus edulis

    Science.gov (United States)

    Gazeau, F.; Gattuso, J.-P.; Dawber, C.; Pronker, A. E.; Peene, F.; Peene, J.; Heip, C. H. R.; Middelburg, J. J.

    2010-07-01

    Several experiments have shown a decrease of growth and calcification of organisms at decreased pH levels. There is a growing interest to focus on early life stages that are believed to be more sensitive to environmental disturbances such as hypercapnia. Here, we present experimental data, acquired in a commercial hatchery, demonstrating that the growth of planktonic mussel (Mytilus edulis) larvae is significantly affected by a decrease of pH to a level expected for the end of the century. Even though there was no significant effect of a 0.25-0.34 pH unit decrease on hatching and mortality rates during the first 2 days of development nor during the following 13-day period prior to settlement, final shells were respectively 4.5±1.3 and 6.0±2.3% smaller at pHNBS~7.8 (pCO2~1100-1200 μatm) than at a control pHNBS of ~8.1 (pCO2~460-640 μatm). Moreover, a decrease of 12.0±5.4% of shell thickness was observed after 15d of development. More severe impacts were found with a decrease of ~0.5 pHNBS unit during the first 2 days of development which could be attributed to a decrease of calcification due to a slight undersaturation of seawater with respect to aragonite. Indeed, important effects on both hatching and D-veliger shell growth were found. Hatching rates were 24±4% lower while D-veliger shells were 12.7±0.9% smaller at pHNBS~7.6 (pCO2~1900 μatm) than at a control pHNBS of ~8.1 (pCO2~540 μatm). Although these results show that blue mussel larvae are still able to develop a shell in seawater undersaturated with respect to aragonite, the observed decreases of hatching rates and shell growth could lead to a significant decrease of the settlement success. As the environmental conditions considered in this study do not necessarily reflect the natural conditions experienced by this species at the time of spawning, future studies will need to consider the whole larval cycle (from fertilization to settlement) under environmentally relevant conditions in order to

  16. Detection of domoic acid in Mytilus galloprovincialis and Ostrea edulis linked to the presence of Nitzschia bizertensis in Bizerte Lagoon (SW Mediterranean)

    Science.gov (United States)

    Bouchouicha-Smida, Donia; Lundholm, Nina; Sahraoui, Inès; Lambert, Christophe; Mabrouk, Hassine Hadj; Hlaili, Asma Sakka

    2015-11-01

    Seasonal variation of DA in bivalves was monitored from August 2008 to March 2009 at a shellfish station in Bizerte Lagoon, one of the most important shellfish areas in Tunisia. At the same time, dynamics of potentially toxic diatoms was studied at six stations in the lagoon. Several diatom strains were isolated, maintained in culture and their identification as well as the toxicity was examined. During the study period, domoic acid (DA) was detected in Tunisia, in both mussels (Mytilus galloprovincialis: 0.13-0.86 μg DA g-1 tissue) and oysters (Ostrea edulis: 0.42-1.04 μg DA g-1 tissue). The amount of DA in the two species was below the EU guideline limits for shellfish (20 μg DA g-1). Within the phytoplankton community, potentially toxic diatoms were observed in high densities (104-106 cells l-1). Among the 9 established cultured strains, seven were identified as the recently described species Nitzschia bizertensis sp. nov, which is apparently a commonly occurring species in the Bizerte Lagoon. Among tested five strains of N. bizertensis, four were confirmed to be toxin producers, containing 2-7 × 10-3 pg DA cell-1 during stationary growth phase. Our results indicate for the first time a Nitzschia species, here Nitzschia bizertensis, could be in relation to accumulation of DA in shellfish. Monitoring of DA in phytoplankton and shellfish should be considered for Bizerte Lagoon in order to gain knowledge about the ecology and toxin-production of N. bizertensis and to explore the risk of DA accumulation in the local shellfish industry caused by this species.

  17. Ion microprobe assessment of the heterogeneity of Mg/Ca, Sr/Ca and Mn/Ca ratios in Pecten maximus and Mytilus edulis (bivalvia shell calcite precipitated at constant temperature

    Directory of Open Access Journals (Sweden)

    H. Kennedy

    2009-01-01

    Full Text Available Small-scale heterogeneity of biogenic carbonate elemental composition can be a significant source of error in the accurate use of element/Ca ratios as geochemical proxies. In this study ion microprobe (SIMS profiles showed significant small-scale variability of Mg/Ca, Sr/Ca and Mn/Ca ratios in new shell calcite of the marine bivalves P. maximus and Mytilus edulis that was precipitated during a constant-temperature culturing experiment. Elevated Mg/Ca, Sr/Ca and Mn/Ca ratios were found to be associated with the deposition of elaborate shell features, i.e. a shell surface stria in P. maximus and surface shell disturbance marks in both species, the latter a common occurrence in bivalve shells. In both species the observed small-scale elemental heterogeneity most likely was not controlled by variable transport of ions to the extra-pallial fluid, but by factors such as shell Mg content influencing Sr and Mn heterogeneity, the influence of shell organic content and/or conditions at the shell crystal-solution interface. Invariant Mg/Ca ratios observed in the mid and innermost regions of the P. maximus shell suggests a potential application as a palaeotemperature proxy.

  18. Effects of substrate type on growth and mortality of blue mussels ( Mytilus edulis ) exposed to the predator Carcinus maenas

    DEFF Research Database (Denmark)

    Frandsen, Rikke; Dolmer, Per

    2002-01-01

    Structure and complexity of the substrate are important habitat characteristics for benthic epifauna. The specific growth and mortality rates and inducible defence characters on medium- sized blue mussels (Mytilus edulis L.) exposed to shore crabs (Carcinus maenas L.) were examined on three...... different substrate types in combined field and laboratory experiments. The experiments showed that complexity of the substrate increased blue mussel survival significantly, through a decrease in predation pressure. However, increased intraspecific competition for food on the complex substrate resulted...... in significantly lower growth rates of the mussels. Inducible defence characters were also influenced by substrate type. Blue mussels were more affected by predators on the structurally simple substrate, where they developed thicker shells and a larger posterior adductor muscle....

  19. Comparison of PCBs and PAHs levels in European coastal waters using mussels from the Mytilus edulis complex as biomonitors

    Directory of Open Access Journals (Sweden)

    Michał Olenycz

    2015-04-01

    Full Text Available Mussels from the Mytilus edulis complex were used as biomonitors for two groups of organic pollutants: polychlorinated biphenyls (PCBs, congeners: 28, 52, 101, 118, 138, 153 and 180 and polycyclic aromatic hydrocarbons (PAHs, naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz(aanthracene, chrysene, benzo(bfluoranthene, benzo(kfluoranthene, benzo(apyrene, indeno(1,2,3-cdpyrene, dibenz(a,hanthracene, benzo(g,h,iperylene at 17 sampling sites to assess their relative bioavailabilities in coastal waters around Europe. Because of the temporal differences in PCBs and PAHs concentrations, data were adjusted using Seasonal Variation Coefficients (SVC before making large-scale spatial comparisons. The highest concentrations of PCBs were found near estuaries of large rivers flowing through urban areas and industrial regions. Elevated bioavailabilities of PAHs occurred in the vicinity of large harbors, urban areas, and regions affected by petroleum pollution as well as in some remote locations, which indicated long-range atmospheric deposition.

  20. Specific 3H-haloperidol binding to dopamine receptors in the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Ishii, Y; Takayanagi, I

    1982-12-01

    The anterior byssus retractor muscle (ABRM) of Mytilus edulis has specific dopamine receptors. We carried out a radioligand binding assay for dopamine receptors in ABRM using (3H)-haloperidol as the radioligand. High affinity binding of (3H)-haloperidol has been shown. Scatchard analysis showed a single component of binding with an apparent equilibrium constant (KD) of 1.6 nM and a maximal number of binding sites (Bmax) of 219 fmoles/mg protein. Some dopamine antagonists displaced 3 nM (3H)-haloperidol binding, and the IC50 and Ki-value of these drugs were calculated. Considering these results, this muscle is thought to be suitable for a study of the dopamine receptors.

  1. [Arginine, octopine and alanine during the tonic and phasic contraction of the anterior byssus retractor muscle of Mytilus edulis].

    Science.gov (United States)

    Devroede, J; Baguet, F

    1982-01-01

    In this work, we compare the energetic cost of tonic and phasic contractions of the anterior byssus retractor muscle (ABRM) of Mytilus edulis. The muscle is stimulated by six different stimulation methods and frozen when it reaches its maximal isometric response. Tonic and phasic tension developments are of similar amplitude and cause a hydrolysis of the same amount of phosphoarginine corresponding to 0.64 mumole per g of muscle and per kg/cm2 of tension (Fig. 1). As compared with the results reported in the literature the values are in good agreement with the biochemical and respiratory measurements, but they are 10 times higher than those measured by the heat production. The total arginine, octopine and alanine contents of those muscles frozen at the peak of contraction are not significantly different from those measured on the resting muscle. On the other hand, these metabolites may show seasonal variations.

  2. Somatic growth of mussels Mytilus edulis in field studies compared to predictions using BEG, DEB, and SFG models

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Filgueira, Ramón; Riisgård, Hans Ulrik

    2014-01-01

    Prediction of somatic growth of blue mussels, Mytilus edulis, based on the data from 2 field-growth studies of mussels in suspended net-bags in Danish waters was made by 3 models: the bioenergetic growth (BEG), the dynamic energy budget (DEB), and the scope for growth (SFG). Here, the standard BEG...... model has been expanded to include the temperature dependence of filtration rate and respiration and an ad hoc modification to ensure a smooth transition to zero ingestion as chlorophyll a (chl a) concentration approaches zero, both guided by published data. The first 21-day field study was conducted...... at nearly constant environmental conditions with a mean chl a concentration of C=2.7μgL−1, and the observed monotonous growth in the dry weight of soft parts was best predicted by DEB while BEG and SFG models produced lower growth. The second 165-day field study was affected by large variations in chl...

  3. Spatial synchronies in the seasonal occurrence of larvae of oysters (Crassostrea gigas) and mussels (Mytilus edulis/galloprovincialis) in European coastal waters

    Science.gov (United States)

    Philippart, Catharina J. M.; Amaral, Ana; Asmus, Ragnhild; van Bleijswijk, Judith; Bremner, Julie; Buchholz, Fred; Cabanellas-Reboredo, Miguel; Catarino, Diana; Cattrijsse, André; Charles, François; Comtet, Thierry; Cunha, Alexandra; Deudero, Salud; Duchêne, Jean-Claude; Fraschetti, Simonetta; Gentil, Franck; Gittenberger, Arjan; Guizien, Katell; Gonçalves, João M.; Guarnieri, Giuseppe; Hendriks, Iris; Hussel, Birgit; Vieira, Raquel Pinheiro; Reijnen, Bastian T.; Sampaio, Iris; Serrao, Ester; Pinto, Isabel Sousa; Thiebaut, Eric; Viard, Frédérique; Zuur, Alain F.

    2012-08-01

    Reproductive cycles of marine invertebrates with complex life histories are considered to be synchronized by water temperature and feeding conditions, which vary with season and latitude. This study analyses seasonal variation in the occurrence of oyster (Crassostrea gigas) and mussel (Mytilus edulis/galloprovincialis) larvae across European coastal waters at a synoptic scale (1000s of km) using standardised methods for sampling and molecular analyses. We tested a series of hypotheses to explain the observed seasonal patterns of occurrence of bivalve larvae at 12 European stations (located between 37°N and 60°N and 27°W and 18°E). These hypotheses included a model that stated that there was no synchronisation in seasonality of larval presence at all between the locations (null hypothesis), a model that assumed that there was one common seasonality pattern for all stations within Europe, and various models that supposed that the variation in seasonality could be grouped according to specific spatial scales (i.e., latitude, large marine ecosystems and ecoregions), taxonomic groups, or several combinations of these factors. For oysters, the best models explaining the presence/absence of larvae in European coastal waters were (1) the model that assumed one common seasonal pattern, and (2) the one that, in addition to this common pattern, assumed an enhanced probability of occurrence from south to north. The third best model for oysters, with less empirical support than the first two, stated that oysters reproduced later in the south than in the north. For mussels, the best models explaining the seasonality in occurrence of larvae were (1) the model that assumed four underlying trends related to large marine ecosystems, and (2) the one that assumed one common seasonal pattern for larvae occurrence throughout Europe. Such synchronies in larval occurrences suggest that environmental conditions relevant to bivalve larval survival are more or less similar at large

  4. The Use of Selected Biomarkers, Phagocytic and Cholinesterase Activity to Detect the Effects of Dimethoate on Marine Mussel (Mytilus edulis

    Directory of Open Access Journals (Sweden)

    KHUSNUL YAQIN

    2008-03-01

    Full Text Available Effects of organophosphorous pesticide, dimethoate on blue mussels, Mytilus edulis using selected biomarkers have been studied. Mussels were exposed to serial dilutions of dimethoate, 7.88, 15.75, 31.35, and 63.00 µg/l including positive and negative controls for 14 days. The suppression effects of dimethoate on phagocytic activity significantly occurred at two lowest concentrations of dimethoate (7.88 and 15.75 µg/l, but stimulation effects significantly emerged at the following highest concentrations (31.35 and 63.00 µg/l. The declining tendency of the cholinesterase (ChE activity (23% lower than the control appeared when mussels exposed to 7.88 and 15.75 µg/l dimethoate. Moreover, the significant inhibition of the ChE activity occurred at 31.35 µg/l dimethoate exposure. This study suggested that the phagocytic and the ChE activity are useful biomarkers for assessing the affects of organophosporous pesticide, dimethoate on neuro-immune system of blue mussels, M. edulis.

  5. Immunomodulation by different types of N-oxides in the hemocytes of the marine bivalve Mytilus galloprovincialis.

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    Caterina Ciacci

    Full Text Available The potential toxicity of engineered nanoparticles (NPs for humans and the environment represents an emerging issue. Since the aquatic environment represents the ultimate sink for NP deposition, the development of suitable assays is needed to evaluate the potential impact of NPs on aquatic biota. The immune system is a sensitive target for NPs, and conservation of innate immunity represents an useful basis for studying common biological responses to NPs. Suspension-feeding invertebrates, such as bivalves, are particularly at risk to NP exposure, since they have extremely developed systems for uptake of nano and microscale particles integral to intracellular digestion and cellular immunity. Evaluation of the effects of NPs on functional parameters of bivalve immunocytes, the hemocytes, may help understanding the major toxic mechanisms and modes of actions that could be relevant for different NP types in aquatic organisms.In this work, a battery of assays was applied to the hemocytes of the marine bivalve Mytilus galloprovincialis to compare the in vitro effects of different n-oxides (n-TiO(2, n-SiO(2, n-ZnO, n-CeO(2 chosen on the basis of their commercial and environmental relevance. Physico-chemical characterization of both primary particles and NP suspensions in artificial sea water-ASW was performed. Hemocyte lysosomal and mitochondrial parameters, oxyradical and nitric oxide production, phagocytic activity, as well as NP uptake, were evaluated. The results show that different n-oxides rapidly elicited differential responses hemocytes in relation to their chemical properties, concentration, behavior in sea water, and interactions with subcellular compartments. These represent the most extensive data so far available on the effects of NPs in the cells of aquatic organisms. The results indicate that Mytilus hemocytes can be utilized as a suitable model for screening the potential effects of NPs in the cells of aquatic invertebrates, and may

  6. Mercury and other trace metals (Ag, Cr, Co, and Ni) in soft tissue and byssus of Mytilus edulis from the east coast of Kyushu Island, Japan.

    Science.gov (United States)

    Szefer, P; Ikuta, K; Frelek, K; Zdrojewska, I; Nabrzyski, M

    1999-05-19

    Concentrations of Hg and other metals such as Ag, Cr, Co and Ni in soft tissues and byssi of the blue mussel (Mytilus edulis) from three sites along the east coast of Kyushu Island, Japan, were determined by a cold-vapor technique. Large inter-regional differences in metal concentrations in both soft tissues and byssi were observed. The tissue concentrations of Hg were significantly greater in M. edulis from the most contaminated locations (Saganoseki) compared to those from a non-industrialized area (Urashiro). It is evident that, compared to the soft tissue, byssus is a more sensitive biomonitor for Hg, Cr, Co and Ni. From the data obtained in the present study evidently results that the soft tissue and especially byssi of M. edulis appear to be good bioindicators for identification of coastal areas exposed to Hg contaminants.

  7. Nutrient regeneration by mussel Mytilus edulis spat assemblages in a macrotidal system

    NARCIS (Netherlands)

    Broekhoven, van W.; Troost, K.; Jansen, H.M.; Smaal, A.C.

    2014-01-01

    Besides exercising grazing control over phytoplankton populations, suspension-feeding bivalves can also stimulate carrying capacity by regeneration of nutrients. This study provides new data on nutrient uptake and release dynamics, and potential implications for availability and stoichiometry of nut

  8. Induction of micronuclei in hemocytes of Mytilus edulis and statistical analysis

    DEFF Research Database (Denmark)

    Wrisberg, M. N.; Bilbo, Carl M.; Spliid, Henrik

    1992-01-01

    A genotoxicity test focusing on micronucleus production in the blood cells (hemocytes) of blue mussel M. edulis has been developed as a possible indicator for marine pollution. A linear dose-response relationship was found when M. edulis was exposed to low concentrations (0, 12.5, and 25 mg...... biological variation, emphasizing the importance of application of a correct statistical method. A systematic approach to the statistical evaluation of the mussel MN test is outlined. The statistical model includes three different situations: (a) estimation of parameters of a single sample, (b) estimation...

  9. Interactions between Mytilus galloprovincialis hemocytes and the bivalve pathogens Vibrio aestuarianus 01/032 and Vibrio splendidus LGP32.

    Science.gov (United States)

    Balbi, T; Fabbri, R; Cortese, K; Smerilli, A; Ciacci, C; Grande, C; Vezzulli, L; Pruzzo, C; Canesi, L

    2013-12-01

    Marine bivalves can accumulate large numbers of bacteria, in particular Vibrio species, whose persistence in bivalve tissues largely depends on their sensitivity to the bactericidal activity of circulating hemocytes and hemolymph soluble factors. The interactions between vibrios and hemolymph have been investigated, in particular in bivalve species susceptible to infection by certain Vibrio spp. and strains. In this work, the effects of two bivalve pathogens, Vibrio splendidus LGP32 (V.s.) and Vibrio aestuarianus 01/032 (V.a.), isolated from oyster mortality outbreaks, on the hemocytes of Mytilus galloprovincialis were investigated. In vitro, V.s., but not V.a., induced a dramatic decrease in lysosomal membrane stability-LMS in the hemocytes; both vibrios induced a moderate lysozyme release, with V.s. > V.a.. The V.s.-induced decrease in LMS was mediated by activation of PI-3Kinase, as shown by use of different kinase inhibitors. TEM analysis showed rapid internalization of both vibrios; however, V.s. lead to cellular and lysosomal damage and was able to survive within the hemocytes, whereas significant killing of V.a. was observed. In vivo, in mussels challenged with either vibrio and sampled at 6, 24 and 96 h post-injection, transient decreases in hemocyte LMS and progressive increases in serum lysozyme activity were observed, with V.s. > V.a.. Moreover, whereas V.a. was efficiently cleared from hemolymph, V.s. showed significant growth, that was maximal at 24 h p.i. when lowest LMS values were recorded in the hemocytes. Both vibrios also induced significant decreases in LMS in the digestive gland, again with V.s. > V.a.. The results indicate distinct interactions between mussel hemocytes and the two vibrio strains tested. The effects of V.s. may be due to the capacity of this strain to interfere with the signaling pathways involved in hemocyte function, thus escaping the bactericidal activity of the host cell, as observed for certain mammalian pathogens

  10. Food competition between Crassostrea gigas and Mytilus edulis in the Oosterschelde estuary

    NARCIS (Netherlands)

    Stehouwer, P.P.

    2006-01-01

    The Pacific oyster (Crassostrea gigas) is an invasive species in the Oosterschelde estuary. It was originally brought there to replace the native flat oyster Ostrea edulis which had been greatly reduced in numbers due to diseases and parasites. Because of some hot summers the pacific oyster could sp

  11. Allometric equations for maximum filtration rate in blue mussels Mytilus edulis and importance of condition index

    DEFF Research Database (Denmark)

    Riisgård, Hans Ulrik; Larsen, Poul Scheel; Pleissner, Daniel

    2014-01-01

    rate (F, l h-1), W (g), and L (mm) as described by the equations: FW = aWb and FL = cLd, respectively. This is done by using available and new experimental laboratory data on M. edulis obtained by members of the same research team using different methods and controlled diets of cultivated algal cells...

  12. Adaptation of the bivalve embryotoxicity assay for the high throughput screening of emerging contaminants in Mytilus galloprovincialis.

    Science.gov (United States)

    Fabbri, Rita; Montagna, Michele; Balbi, Teresa; Raffo, Enrico; Palumbo, Franca; Canesi, Laura

    2014-08-01

    Emerging contaminants (such as Endocrine disrupting chemicals-EDCs, brominated and perfluorinated compounds-BFRs and PFCs, pharmaceuticals) are chemicals currently not included in regulatory monitoring programs, and whose fate and biological impacts are poorly understood. Assessment of ecosystem health with respect to these chemicals is of particular concern also in the marine environment: in this respect, data on the effects on early life stages are important to establish the sensitivity of marine species. In this work, the acute (48 h) bivalve embryo toxicity test was applied for screening the developmental effects of different emerging contaminants in the Mediterranean mussel Mytilus galloprovincialis. The assay was adapted to 96-microwell plates, and standardized in order to obtain to normal D-shaped larvae with acceptability of test results based on negative control and positive control (copper) comparable with those reported in literature for Mytilus spp. The effects of different model compounds representative of EDCs (Nonylphenol-NP and Bisphenol A-BPA), BFRs (Tetrabromobisphenol A-TBBPA), PFCs (perfluorooctanoid acid-PFOA and perfluorooctane sulphonate-PFOAS) and pharmaceuticals (Ibuprofen-IBU, Diclofenac-DCF, Bezafibrate-BEZA) in a wide concentration range (0.01-0.1-1-10-100-1000 μg/L) were evaluated. The assay proved as a sensitive tool for high throughput screening of emerging contaminants in a marine species, leading to production of significant amounts of data that may be useful for regulatory purposes.

  13. Detoxification and protein quality control markers in the mussel Mytilus edulis (Linnaeus) exposed to crude oil: Salinity-induced modulation

    Science.gov (United States)

    Lysenko, Liudmila; Sukhovskaya, Irina; Borvinskaya, Ekaterina; Krupnova, Marina; Kantserova, Nadezda; Bakhmet, Igor'; Nemova, Nina

    2015-12-01

    Marine and coastal ecosystems are influenced by oil from chronic contamination or sporadic oil spills. An oil spill was simulated in an aquarium-based experiment designed to reproduce interactions of crude oil with inert environmental components, particularly adhesion on shore gravel and dissolution in sea water. Total experimental oil concentrations were in the range of comparable hydrocarbon concentrations following an oil spill. Furthermore, the possible interaction of a chemical (anthropogenic) stressor, such as oil PAHs, and a "natural" stressor like desalination, was simulated. In order to assess the biological effects of crude oil contamination and desalination (each individually and in combination) on the blue mussel Mytilus edulis L., biochemical responses were estimated including: detoxification capacity by glutathione-S-transferase (GST) activity, reduced glutathione (GSH) level, and protein quality control by autophagy-related proteases cathepsin B (CatB), cathepsin D (CatD), and calcium-dependent calpain-like proteases. Oil treatment stimulated defense system response in the mussels with primary effects on GST and protease-mediated reactions such as the activation of CatB, CatD, and calpains. Most of biomarkers responded to oil in a dose- and time-dependent manner. Additional environmental stress, such as desalination, promoted the oil-induced activation of GST and CatD while resulting in a delay or impairement of the defense response to oil by GSH and proteases CatB and calpains. Thus, biomarker data shows that combined effects of oil compounds and desalination can be realized in both a synergistic and an antagonistic manner. The evaluated interaction between oil pollution effects and sub-optimal salinity on M. edulis indicates the potential risk of maladaptation to the biota of estuaries.

  14. Growth-Prediction Model for Blue Mussels (Mytilus edulis on Future Optimally Thinned Farm-Ropes in Great Belt (Denmark

    Directory of Open Access Journals (Sweden)

    Poul S. Larsen

    2016-07-01

    Full Text Available A recently developed BioEnergetic Growth (BEG model for blue mussels (Mytilus edulis, valid for juvenile mussels, has been further developed to an ‘extended model’ and an alternative ‘ad hoc BEG model’ valid for post-metamorphic mussels, where the latter accounts for changing ambient chl a concentration. It was used to predict the growth of M. edulis on optimally thinned farm-ropes in Great Belt (Denmark, from newly settled post-metamorphic mussels of an initial shell size of 0.8 mm to marketable juvenile 30–35 mm ‘mini-mussels’. Such mussels will presumably in the near future be introduced as a new Danish, smaller-sized consumer product. Field data for actual growth (from Day 0 = 14 June 2011 showed that size of ‘mini-mussel’ was reached on Day 109 (Oct 1 and length 38 mm on Day 178 (Dec 9 while the corresponding predictions using the extended model were Day 121 (Oct 13 and Day 159 (Nov 20. Similar results were obtained by use of the ad hoc BEG model which also demonstrated the sensitivity of growth prediction to levels of chl a concentration, but less to temperature. The results suggest that it is possible (when the conditions are optimal, i.e., no intraspecific competition ensured by sufficient thinning to produce ‘mini-mussels’ in Great Belt during one season, but not the usual marketable 45-mm mussels. We suggest that the prediction model may be used as a practical instrument to evaluate to what degree the actual growth of mussels on farm ropes due to intraspecific competition may deviate from the potential (optimal growth under specified chl a and temperature conditions, and this implies that the effect of thinning to optimize the individual growth by eliminating intraspecific competition can be rationally evaluated.

  15. Differential patterns of male and female mtDNA exchange across the Atlantic Ocean in the blue mussel, Mytilus edulis.

    Science.gov (United States)

    Riginos, Cynthia; Hickerson, Michael J; Henzler, Christine M; Cunningham, Clifford W

    2004-11-01

    Comparisons among loci with differing modes of inheritance can reveal unexpected aspects of population history. We employ a multilocus approach to ask whether two types of independently assorting mitochondrial DNAs (maternally and paternally inherited: F- and M-mtDNA) and a nuclear locus (ITS) yield concordant estimates of gene flow and population divergence. The blue mussel, Mytilus edulis, is distributed on both North American and European coastlines and these populations are separated by the waters of the Atlantic Ocean. Gene flow across the Atlantic Ocean differs among loci, with F-mtDNA and ITS showing an imprint of some genetic interchange and M-mtDNA showing no evidence for gene flow. Gene flow of F-mtDNA and ITS causes trans-Atlantic population divergence times to be greatly underestimated for these loci, although a single trans-Atlantic population divergence time (1.2 MYA) can be accommodated by considering all three loci in combination in a coalescent framework. The apparent lack of gene flow for M-mtDNA is not readily explained by different dispersal capacities of male and female mussels. A genetic barrier to M-mtDNA exchange between North American and European mussel populations is likely to explain the observed pattern, perhaps associated with the double uniparental system of mitochondrial DNA inheritance.

  16. An integrated biomarker response index for the mussel Mytilus edulis based on laboratory exposure to anthracene and field transplantation experiments

    Science.gov (United States)

    Yuan, Mengqi; Wang, You; Zhou, Bin; Jian, Xiaoyang; Dong, Wenlong; Tang, Xuexi

    2016-10-01

    Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to construct an integrated biomarker response (IBR) index using Mytilus edulis. Mussels were exposed to the polycyclic aromatic hydrocarbon anthracene under controlled laboratory conditions and the activities of components of the glutathione antioxidant system, and the concentrations of oxidative-damage markers, were measured in the gills and digestive glands. Anthracene exposure resulted in increased levels of malondialdehyde (MDA) and superoxide radicals (O{2/-}•), indicating that oxidative damage had occurred. Correspondingly, anthracene exposure induced increased activities of glutathione S -transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH) in digestive glands, and GPx and glutathione reductase (GR) in gills, consistent with stimulation of the antioxidant system. A field experiment was set up, in which mussels from a relatively clean area were transplanted to a contaminated site. One month later, the activities of GST, GPx and GR had increased in several tissues, particularly in the digestive glands. Based on the laboratory experiment, an IBR, which showed a positive relationship with anthracene exposure, was constructed. The IBR is suggested to be a potentially useful tool for assessing anthracene pollution.

  17. Mg-ATPase activity and motility of native thick filaments isolated from the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Yamada, A; Ishii, N; Shimmen, T; Takahashi, K

    1989-04-01

    A method for isolating native thick filaments from the anterior byssus retractor muscle (ABRM) of Mytilus edulis is described. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the isolated thick filament preparation contained mainly paramyosin and myosin but almost no actin. Electron microscopy of negatively stained preparations showed that the isolated thick filaments were tapered at both ends and of various sizes, in the range 5-31 microns in length and 51-94nm in width in the central region. Central bare zones were observed in the smaller filaments, but were not clearly seen in the larger filaments. Mg-ATPase activity of the isolated thick filaments was activated by skeletal muscle F-actin in a Ca2+-dependent manner. The maximal activity was about 20 nmol min-1 mg-1 thick filaments (20 degrees C, pH7.0). Motility of the thick filaments attached to latex beads (diameter, 2 microns) was also studied using the native actin cables of the freshwater alga, Chara. In the presence of Mg-ATP and Ca2+, the beads moved along the actin cables at a maximal velocity of about 1 micron s-1. In the absence of Ca2+, almost no movement was observed. These results show that the isolated thick filaments are structurally intact and retain the essential mechanochemical characteristics of the ABRM myosin.

  18. Tension and heat production during isometric contractions and shortening in the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Gilbert, S H

    1978-09-01

    1. Tension and heat production were measured during phasic isometric contractions and isovelocity shortening in the anterior byssus retractor muscle (ABRM) of Mytilus edulis at 20 degrees C. 2. Isometric tension at lo was 550 +/- 40 mN/mm2 (S.D. for 173 observations in nine muscles), while the isometric maintenance heat rate was 1.0 +/- 0.2 mW/g wet wt. (S.D. for seventy-eight observations in eight muscles). 3. Isometric tension and heat production were measured as functions of muscle length over a range of 0.79--1.14 lo and were found to bear a linear relation to each other. 4. The force-velocity relation was determined in isovelocity releases imposed during tetanic stimulation and was found to fit the Hill equation with parameters alpha/Po = 0.07 +/- 0.01 and b/lo = 0.016 +/- 0.0007 sec-1 (S.E. from non-linear least-squares regression of the pooled data from seven experiments). 5. Heat production measured in the same experiments showed that shortening heat is produced with a shortening heat coefficient alpha/Po of 0.15. Shortening heat does not appear to be force-dependent, and separate experiments confirmed that it is a linear function of the amount of shortening.

  19. Integrated biomarker response index used in laboratory exposure of the mussel Mytilus edulis to water accommodated fractions of crude oil

    Science.gov (United States)

    Yuan, Mengqi; Wang, You; Zhang, Xinxin; Hu, Shunxin; Tang, Xuexi

    2017-03-01

    Oil pollution is a serious environmental problem in coastal areas and to set up a quantitative evaluation method in monitoring the environmental pollution is of great importance. Individuals of Mytilus edulis, collected from the coastal area of Qingdao, were thus exposed to the water accommodated fractions (WAFs) of crude oil under controlled lab conditions. Mussels were exposed to different concentrations of WAFs for 96h acute toxicity experiment and 15d chronic toxicity experiment, a 7d restoration experiment was conducted after toxicity experiment as well. The activities of the antioxidant enzymes (CAT, GST, GPx and GR) were measured in gills of mussels. The purpose of the study was to screen out a series of sensitive biomarkers and set up an Integrated Biomarker Response index (IBR) for marine oil pollution monitoring. Results showed: (1) WAFs exposure induced the increased activities of CAT, GST, GPx and GR in gills, revealing a stimulation effect on the antioxidant system. Activities of enzymes were more significantly altered in response to higher concentrations of WAFs (2.3 and 5.0 mg.L-1) than lower concentrations (0.5 and 1.1 mg.L-1). After restoration experiment, the activities decreased to the initial levels. (2) IBR was set up base on the laboratory experiment, which showed a positive relationship with WAFs exposure concentrations. Therefore, IBR was suggested to be a potentially useful tool in assessing the oil pollution.

  20. Length- and weight-dependent clearance rates of juvenile mussels ( Mytilus edulis) on various planktonic prey items

    Science.gov (United States)

    Jacobs, P.; Troost, K.; Riegman, R.; van der Meer, J.

    2015-03-01

    Filtration capacity and feeding behaviour has been intensely studied for adult mussels ( Mytilus edulis), but less information is available for juvenile mussels (1.5-25 mm, mussel seed collectors in the Netherlands prompted the need for more detailed information on juvenile mussel behaviour. To estimate the impact of juvenile populations on ecosystem carrying capacity, information on clearance rate as well as usage of different prey items is essential. Clearance rates were measured in an experimental study, incubating juvenile mussels in natural sea water. Rates were related to isometrics as well as specified for the prey items bacteria, picophytoplankton (mussels depends on shell length2, while the relationship between clearance rate and weight was more variable. Length is thus a better parameter for estimating clearance rate than weight. Ciliates and nanophytoplankton were cleared at comparable, but variable rates, while picoalgae were cleared from the water at the rate of 11-64 % compared to nanophytoplankton. For bacteria, the clearance rate was on average 9 %. This study showed different retention of particles of similar size (picoalgae and bacteria) as well as variability in particle retention for the different prey items. This variable retention efficiency could not be related to seston concentration nor to dominance in cell size. The results from this study can be used to estimate the effect of mussel seed collectors on the carrying capacity of the Dutch Wadden Sea.

  1. Organochlorine compounds in blue mussels, Mytilus edulis, and Pacific oysters, Crassostrea gigas, from seven sites in the Lower Saxonian Wadden Sea, Southern North Sea.

    Science.gov (United States)

    Dörr, Barbara; Liebezeit, Gerd

    2009-12-01

    Blue mussels (Mytilus edulis) and Pacific oysters (Crassostrea gigas) collected at seven locations in the Lower Saxonian Wadden Sea in January and February 2007 were analysed for organochlorine compounds. Contaminants were present in all samples, albeit with variable amounts and composition. The highest values were found in the Jade Bay. Congener PCB 153 was the contaminant which had the highest content of all organochlorines tested (475.75-937.39 ng/g lipid). DDT was detected in one sample only while DDD and DDE were found in all samples, the latter with contents up to 351.34 ng/g lipid. No clear differentiation could be made in terms of accumulation of organochlorines for M. edulis and C. gigas. Comparison with data from 2001 to 2006 showed an increase in 2007, which may be due to the different season the samples were taken.

  2. Evidence for immunomodulation and apoptotic processes induced by cationic polystyrene nanoparticles in the hemocytes of the marine bivalve Mytilus.

    Science.gov (United States)

    Canesi, L; Ciacci, C; Bergami, E; Monopoli, M P; Dawson, K A; Papa, S; Canonico, B; Corsi, I

    2015-10-01

    Polymeric nanoparticles can reach the marine environment from different sources as weathering of plastic debris and nanowaste. Nevertheless, few data are available on their fate and impact on marine biota. Polystyrene nanoparticles (PS NPs) can be considered as a model for studying the effects of nanoplastics in marine organisms: recent data on amino-modified PS NPs (PS-NH2) toxicity in sea urchin embryos underlined that marine invertebrates can be biological targets of nanoplastics. Cationic PS NPs have been shown to be toxic to mammalian cells, where they can induce apoptotic processes; however, no information is available on their effects and mechanisms of action in the cells of marine organisms. In this work, the effects of 50 nm PS-NH2 were investigated in the hemocytes of the marine bivalve Mytilus galloprovincialis. Hemocytes were exposed to different concentrations (1, 5, 50 μg/ml) of PS-NH2 suspension in ASW. Clear signs of cytoxicity were evident only at the highest concentrations (50 μg/ml). On the other hand, a dose dependent decrease in phagocytic activity and increase in lysozyme activity were observed. PS-NH2 NPs also stimulated increase in extracellular ROS (reactive oxygen species) and NO (nitric oxide) production, with maximal effects at lower concentrations. Moreover, at the highest concentration tested, PS-NH2 NPs induced apoptotic process, as evaluated by Flow cytometry (Annexin V binding and mitochondrial parameters). The results demonstrate that in marine invertebrates the immune function can represent a significant target for PS-NPs. Moreover, in Mytilus hemocytes, PS-NH2 NPs can act through mechanisms similar to those observed in mammalian cells. Further research is necessary on specific mechanisms of toxicity and cellular uptake of nanoplastics in order to assess their impact on marine biota.

  3. Development of marine sediment toxicity identification evaluation methods using Strongylocentrotus purpuratus, Mytilus edulis, and Eohaustorius estuarius

    Energy Technology Data Exchange (ETDEWEB)

    Wortham, G.; Cotsifas, J.S.; Taberski, K.; Hansen, S.R. [S.R. Hansen and Associates, Concord, CA (United States)

    1994-12-31

    Widespread sediment toxicity, including ``clean`` reference sites, dictates that the causes of toxicity in sediments be determined. Toxicity Identification Evaluations (TIE) are useful tools in characterizing compounds responsible for toxicity, but were unavailable for sediment samples. TIE methods were developed for sediment porewater and included the following components: determination of an appropriate porewater extraction process; control TIE tests using marine water and porewater evaluating species sensitivities to the fractionation procedures; validation experiments investigating the removal efficiencies of organics using C18 solid phase extraction, and metals chelation using EDTA and STS; spiking experiments to determine the effectiveness of the TIE procedure in identifying multiple toxicants. The authors determined that fractionation procedures could be applied to both marine water and porewater using S. purpuratus, M. edulis and E. estuarius as biological detectors.

  4. Mussel shells of Mytilus edulis as bioarchives of the distribution of rare earth elements and yttrium in seawater and the potential impact of pH and temperature on their partitioning behavior

    Science.gov (United States)

    Ponnurangam, A.; Bau, M.; Brenner, M.; Koschinsky, A.

    2016-02-01

    Mussel shells are potential bioarchives of proxies for changes in the physicochemical conditions in the bivalve's habitat. One such proxy is the distribution of rare earths and yttrium (REY) in seawater, as REY speciation in seawater is sensitive to pH and temperature variations, due to the impact of these parameters on the activity of CO32- in seawater. We present a new protocol for sample preparation and determination of ultratrace concentrations of REY in bulk bivalve shells (comprised of calcite and aragonite) that includes sample treatment with NaOCl followed by REY separation and preconcentration. The data obtained were used to calculate REY partition coefficients between bulk bimineralic shells of Mytilus edulis (calcite aragonite mix) and ambient seawater, and the results acquired were then used to investigate the potential effects of pH and temperature on REY partitioning.Shells of Mytilus edulis mussels from the North Sea show consistent shale-normalized (SN) REY patterns that increase from the light REY to the middle REY and decrease from the middle REY to the heavy REY. Despite being different from the general seawater REYSN pattern, the shells still display distinct REY features of seawater, such as a negative CeSN anomaly and small positive YSN and GdSN anomalies. Apparent REY partition coefficients between shells and seawater (appDTot.REYshell/seawater) are low and decrease strongly from the light REY (4.04 for La) to the heavy REY (0.34 for Lu). However, assuming that only the free REY3+ are incorporated into the shell, modDFreeREY3+shell/seawater values are higher and comparatively similar for all REY (102.46 for La; 113.44 for Lu) but show a slight maximum at Tb (199.18). Although the impact of vital effects, such as REY speciation in a mussel's extrapallial fluid from which the carbonate minerals precipitate, cannot be quantified yet, it appears that M. edulis shells are bioarchives of some REY features of seawater.We modeled the REYSN patterns

  5. Modeling and predicting the growth of the mussel, Mytilus edulis: implications for planning of aquaculture and eutrophication mitigation.

    Science.gov (United States)

    Bergström, Per; Lindegarth, Susanne; Lindegarth, Mats

    2015-12-01

    The increased pressure on the marine ecosystems highlights the need for policies and integrated approaches for sustainable management of coastal areas. Spatial planning based on geographic information of human activities, ecological structures and functions, and their associated goods and services is a fundamental component in this context. Here, we evaluate the potential of predictive modeling to provide spatial data on one ecosystem function, mussel growth for use in such processes. We developed a methodology based on statistical modeling, spatial prediction, and mapping for the relative growth of the blue mussel, Mytilus edulis. We evaluated the performance of different modeling techniques and classification schemes using empirical measurements of growth from 144 sampling sites and data on biological, chemical, and physical predictors. Following comparisons of the different techniques and schemes, we developed random forest models to predict growth along the Swedish west coast. Implemented into GIS the best model produced in this study predicts that low, intermediate, and high growth rates can be expected in 53%, 32%, and 15% of modeled area, respectively. The results of this study also suggest that the nature and quality of predictor data hold the key to improving the predictive power of models. On a more general note, this study exemplifies a feasible approach based on measuring, modeling, and mapping for obtaining scientifically based spatial information on ecosystem functions and services affected by a complex set of factors. Such information is fundamental for maritime spatial planning and ecosystem-based management and its importance is likely to increase in the future. Because of its close link to nutrient assimilation and production yield, site-specific information of soft tissue growth such as the map of predicted growth rate developed in this study can be used as a tool for optimizing actions aimed at mitigating eutrophication and aquaculture

  6. Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis.

    Science.gov (United States)

    Nielsen, Lasse Tor; Hansen, Per Juel; Krock, Bernd; Vismann, Bent

    2016-07-01

    Okadaic acid (OA), dinophysistoxins (DTX) and pectenotoxins (PTX) produced by the dinoflagellates Dinophysis spp. can accumulate in shellfish and cause diarrhetic shellfish poisoning upon human consumption. Shellfish toxicity is a result of algal abundance and toxicity as well as accumulation and depuration kinetics in mussels. We mass-cultured Dinophysis acuta containing OA, DTX-1b and PTX-2 and fed it to the blue mussel, Mytilus edulis under controlled laboratory conditions for a week to study toxin accumulation and transformation. Contents of OA and DTX-1b in mussels increased linearly with incubation time, and the net toxin accumulation was 66% and 71% for OA and DTX-1b, respectively. Large proportions (≈50%) of both these toxins were transformed to fatty acid esters. Most PTX-2 was transformed to PTX-2 seco-acid and net accumulation was initially high, but decreased progressively throughout the experiment, likely due to esterification and loss of detectability. We also quantified depuration during the subsequent four days and found half-life times of 5-6 days for OA and DTX-1b. Measurements of dissolved toxins revealed that depuration was achieved through excreting rather than metabolizing toxins. This is the first study to construct a full mass balance of DSP toxins during both accumulation and depuration, and we demonstrate rapid toxin accumulation in mussels at realistic in situ levels of Dinophysis. Applying the observed accumulation and depuration kinetics, we model mussel toxicity, and demonstrate that a concentration of only 75 Dinophysis cells l(-1) is enough to make 60 mm long mussels exceed the regulatory threshold for OA equivalents.

  7. Redox proteomic analysis of mytilus edulis gills: effects of the pharmaceutical diclofenac on a non-target organism.

    Science.gov (United States)

    Jaafar, Siti Nur Tahirah; Coelho, Ana Varela; Sheehan, David

    2015-10-01

    Veterinary and human pharmaceuticals are an emerging category of chemical pollutants with potential to cause serious toxicity to non-target organisms. Filter-feeding aquatic organisms such as mussels are especially threatened. In this study, the blue mussel, Mytilus edulis, was exposed to two doses (0.2 mg/L and 1 mg/L) of the anti-inflammatory diclofenac. Effects on the gill, the principal feeding organ of mussels, were investigated. It was noted that, while no effect was evident on gill glutathione transferase or catalase activities, there was a tissue-specific increase in glutathione reductase activity and reduction in total protein thiol groups. Two dimensional electrophoresis was performed and some affected proteins identified by in-gel tryptic digestion and peptide mass fingerprinting. Of these, four unique proteins (caspase 3/7-4, heat-shock cognate protein 70, a predicted enolase-like protein, arginine kinase) were found to be oxidized whilst eight unique proteins (β-tubulin, actin, isocitrate dehydrogenase, arginine kinase, heavy metal-binding HIP, cytosolic malate dehydrogenase, proteasome subunit alpha type 2, Mg: bb02e05 (glyceraldehyde-3-phosphate dehydrogenase) and superoxide dismutase) were found to have altered abundance. In addition, bioinformatic analysis suggested putative identities for six hypothetical proteins which either were oxidized or decreased in abundance. These were; 78 kDa glucose-regulated protein precursor, α-enolase, calreticulin, mitochondrial H + -ATPase, palmitoyl protein thioesterase 1 and initiation factor 5a. It is concluded that diclofenac causes significant oxidative stress to gills and that this affects key structural, metabolic and stress-response proteins.

  8. Somatic growth of mussels Mytilus edulis in field studies compared to predictions using BEG, DEB, and SFG models

    Science.gov (United States)

    Larsen, Poul S.; Filgueira, Ramón; Riisgård, Hans Ulrik

    2014-04-01

    Prediction of somatic growth of blue mussels, Mytilus edulis, based on the data from 2 field-growth studies of mussels in suspended net-bags in Danish waters was made by 3 models: the bioenergetic growth (BEG), the dynamic energy budget (DEB), and the scope for growth (SFG). Here, the standard BEG model has been expanded to include the temperature dependence of filtration rate and respiration and an ad hoc modification to ensure a smooth transition to zero ingestion as chlorophyll a (chl a) concentration approaches zero, both guided by published data. The first 21-day field study was conducted at nearly constant environmental conditions with a mean chl a concentration of C = 2.7 μg L- 1, and the observed monotonous growth in the dry weight of soft parts was best predicted by DEB while BEG and SFG models produced lower growth. The second 165-day field study was affected by large variations in chl a and temperature, and the observed growth varied accordingly, but nevertheless, DEB and SFG predicted monotonous growth in good agreement with the mean pattern while BEG mimicked the field data in response to observed changes in chl a concentration and temperature. The general features of the models were that DEB produced the best average predictions, SFG mostly underestimated growth, whereas only BEG was sensitive to variations in chl a concentration and temperature. DEB and SFG models rely on the calibration of the half-saturation coefficient to optimize the food ingestion function term to that of observed growth, and BEG is independent of observed actual growth as its predictions solely rely on the time history of the local chl a concentration and temperature.

  9. Absence of aryl hydrocarbon hydroxylase (AHH) in three marine bivalves

    Energy Technology Data Exchange (ETDEWEB)

    Vandermeulen, J.H. (Bedford Inst. of Oceanography, Dartmouth, Nova Scotia); Penrose, W.R.

    1978-05-01

    Bivalves exposed to short-term (4 d) and long-term (6 yr) oil pollution were assayed for aryl hydrocarbon hydroxylase (AHH) and N-demethylase activity. Short-term induction studies were carried out on Mya arenaria, Mytilus edulis, and Ostrea edulis incubated in aqueous extracts of Kuwait crude oil or Bunker C (fuel) oil. For the chronic-induction studies Mya arenaria and Mytilus edulis were collected from oiled clam beds (Arrow Bunker C) in Chedabucto Bay, Nova Scotia. None of the bivalves showed any basal or petroleum-hydrocarbon-induced aryl hydrocarbon hydroxylase or N-demethylase activity, as shown by their inability to metabolize benzopyrene or imipramine. In contrast, oil-free control trout and trout taken from a polluted lake readily metabolized both these compounds. The inability of these bivalves to degrade petroleum aromatic hydrocarbons and the tendency of these compounds to accumulate in their tissues present an opportunity for transfer of unaltered hydrocarbons into the food chain.

  10. Biomonitoring of mercury pollution in a wetland near Ravenna, Italy by translocated bivalves (Mytilus galloprovincialis)

    Energy Technology Data Exchange (ETDEWEB)

    Cattani, O.; Fabbri, D.; Salvati, M.; Trombini, C.; Vassura, I.

    1999-08-01

    An active biomonitoring experiment using mussels (Mytilus galloprovincialis) was performed in Pialassa Baiona, a mercury-polluted coastal wetland near Ravenna, Italy. Three stations (A, B, and C) were selected along the south to north axis. Following a 52-d field exposure, organisms transplanted in the southernmost polluted area (station A) showed mean mercury concentration values of 660 ng/g (dry weight), 4.4 times the initial background level, and were still accumulating mercury. Mussels in both the central area (station B) and the northern area (station C) seemed to reach a steady state with mean mercury concentration values of 323 and 412 ng/g, respectively. This field experiment is the first study carried out in the Ravenna wetlands to evaluate mercury bioavailability in this environment. Finally, the efficiency of the population of Mytilus galloprovincialis selected for the field experiment as mercury bioaccumulators was tested in a laboratory experiment that revealed that up to 135 {micro}g/g (dry weight) could be reached after 77 d of exposure to mercury-polluted water.

  11. Distribution and association of trace metals in soft tissue and byssus of Mytilus edulis from the east coast of Kyushu Island, Japan.

    Science.gov (United States)

    Szefer, P; Ikuta, K; Kushiyama, S; Szefer, K; Frelek, K; Geldon, J

    1997-02-01

    Concentrations of Cd, Pb, Zn, Cu, Ag, Cr, Co Ni, Mn, andFe in soft tissues and byssi of blue mussel (Mytilus edulis) fromthree sites along the east coast of Kyushu Island, Japan, were determined byAAS method. Large inter-regional differences in metal concentrations in bothsoft tissues and byssi (Cu, Cd, and Pb and Cu, Pb, Co, Ni, Mn, and Fe,respectively) were recorded. Highly significant correlations (pbyssus are useful in detectingsome areas of some metallic contaminants. The high concentrations of Cd, andespecially Pb and Cu, in Saganoseki mussels and moderately elevatedconcentrations of these metals in Akamizu mussels may be attributed to theanthropogenic emissions from a metallic refinery and an artificial fiberfactory, respectively. It is evident that, compared to the soft tissue, theincrease of Cu levels relative to Zn levels in the byssi of M.edulis are eight times higher, with a slope b (Cu/Zn) of 7.5 for byssusand 0.93 for soft tissue. This suggests that byssus, as compared to softtissue, is a more sensitive bioindicator for Cu. From the data obtained, thesoft tissue and especially byssi of M. edulis appear to be goodbioindicators for identification of coastal areas exposed to metalliccontaminants.

  12. Match/mismatch between the Mytilus edulis larval supply and seston quality: effect on recruitment.

    Science.gov (United States)

    Toupoint, Nicolas; Gilmore-Solomon, Lisandre; Bourque, François; Myrand, Bruno; Pernet, Fabrice; Olivier, Frédéric; Tremblay, Réjean

    2012-08-01

    We considered Cushing's match/mismatch theory in a heterotrophic environment and hypothesized that settlement and recruitment success in blue mussel are higher when the food supply is rich in polyunsaturated and essential fatty acids (PUFA/EFA). To test this hypothesis, we monitored larval development as well as fatty acid composition in trophic resources during two successive reproductive seasons. The decoupling we found between the presence of competent larvae in the water column and settlement rates strongly suggests that metamorphosis is delayed until conditions are suitable. In both years, the major mussel settlement peak was synchronized with a phytoplanktonic pulse rich in EFA, consisting of a large autotrophic bloom in 2007 and a short but substantial peak of picoeukaryotes in 2008. These results suggest a "trophic settlement trigger" that indirectly affects recruitment by strongly improving the settlement rate. Despite similar larval settlement rates during both years, the lower 2007 recruitment likely resulted from a mismatch with a high lipid-quality trophic resource. The seasonal trophic conditions differed greatly between the two years, with fatty acids profiles reflecting heterotrophic plankton production in 2007 and mostly autotrophic production in 2008. In agreement with Cushing's theory, our results highlight a match/mismatch, related to the food lipid quality rather than food quantity. For the first time, we show that the recruitment in marine bivalves may be dependent on phytoplanktonic pulses characterized by high levels of PUFA.

  13. Spatial and temporal distribution of mercury and methylmercury in bivalves from the French coastline.

    Science.gov (United States)

    Briant, N; Chouvelon, T; Martinez, L; Brach-Papa, C; Chiffoleau, J F; Savoye, N; Sonke, J; Knoery, J

    2017-01-30

    Marine mercury (Hg) concentrations have been monitored in the French coastline for the last half a century using bivalves. The analyses presented in this study concerned 192 samples of bivalves (mussels: Mytilus edulis and Mytilus galloprovincialis and oysters: Crassostrea gigas and Isognomon alatus) from 77 sampling stations along the French coast and in the French Antilles sea. The goals of this study were to assess MeHg levels in various common bivalves from French coastline, and to identify possible geographic, taxonomic or temporal variations of concentrations. We show that the evolution of methylmercury (MeHg) concentrations covary with total mercury (HgT) concentrations. Moreover, in most of the study sites, HgT concentrations have not decreased since 1987, despite regulations to decrease or ban mercury used for anthropic activities.

  14. Comprehensive Study of the Influence of Altered Gravity on the Oxidative Burst of Mussel ( Mytilus edulis) Hemocytes

    Science.gov (United States)

    Unruh, E.; Brungs, S.; Langer, S.; Bornemann, G.; Frett, T.; Hansen, P.-D.

    2016-06-01

    Microgravity induces alterations in the functioning of immune cell; however, the underlying mechanisms have not yet been identified. In this study, hemocytes (blood cells) of the blue mussel Mytilus edulis were investigated under altered gravity conditions. The study was conducted on the ground in preparation for the BIOLAB TripleLux-B experiment, which will be performed on the International Space Station (ISS). On-line kinetic measurements of reactive oxygen species (ROS) production during the oxidative burst and thus cellular activity of isolated hemocytes were performed in a photomultiplier (PMT)-clinostat (simulated microgravity) and in the 1 g operation mode of the clinostat in hypergravity on the Short-Arm Human Centrifuge (SAHC) as well as during parabolic flights. In addition to studies with isolated hemocytes, the effect of altered gravity conditions on whole animals was investigated. For this purpose, whole mussels were exposed to hypergravity (1.8 g) on a multi-sample incubator centrifuge (MuSIC) or to simulated microgravity in a submersed clinostat. After exposure for 48 h, hemocytes were taken from the mussels and ROS production was measured under 1 g conditions. The results from the parabolic flights and clinostat studies indicate that mussel hemocytes respond to altered gravity in a fast and reversible manner. Hemocytes (after cryo-conservation) exposed to simulated microgravity ( μ g), as well as fresh hemocytes from clinorotated animals, showed a decrease in ROS production. Measurements during a permanent exposure of hemocytes to hypergravity (SAHC) show a decrease in ROS production. Hemocytes of mussels measured after the centrifugation of whole mussels did not show an influence to the ROS response at all. Hypergravity during parabolic flights led to a decrease but also to an increase in ROS production in isolated hemocytes, whereas the centrifugation of whole mussels did not influence the ROS response at all. This study is a good example how

  15. Microplastics in bivalves cultured for human consumption.

    Science.gov (United States)

    Van Cauwenberghe, Lisbeth; Janssen, Colin R

    2014-10-01

    Microplastics are present throughout the marine environment and ingestion of these plastic particles (microplastics in two species of commercially grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on average 0.36 ± 0.07 particles g(-1) (wet weight), while a plastic load of 0.47 ± 0.16 particles g(-1) ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amount to 11,000 microplastics per year. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estimating microplastic toxicity, estimations of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible.

  16. Heavy metal concentrations and biomarkers of oxidative stress in native mussels (Mytilus edulis chilensis) from Beagle Channel coast (Tierra del Fuego, Argentina).

    Science.gov (United States)

    Duarte, Claudia A; Giarratano, Erica; Amin, Oscar A; Comoglio, Laura I

    2011-08-01

    The aim of this study was to evaluate the usefulness of oxidative stress biomarkers of pollution in native mussels Mytilus edulis chilensis from the Beagle Channel. Spatial and seasonal variations of catalase, glutathione-S-transferase and lipid peroxidation in gills and digestive gland were analyzed in relation to environmental parameters, heavy metals in sediment and in tissue. Four sites with anthropogenic impact and a control site were selected and monitored during the four seasons of 2007. We found significant differences among sites in concentrations of dissolved nutrients and heavy metals in sediments, with the highest values recorded at sites with anthropogenic pressure. Different patterns were observed between concentrations of metals in tissues and in sediments suggesting differences in bioavailability. There were also significant differences in biomarker responses among sites, despite the strong seasonal variability. Our results showed relatively moderate levels of pollution in the study area as a result of urban influences.

  17. Major and minor arsenic compounds accounting for the total urinary excretion of arsenic following intake of blue mussels (Mytilus edulis): A controlled human study

    DEFF Research Database (Denmark)

    Molin, M.; Ydersbond, T.A.; Ulven, S.M.;

    2012-01-01

    Blue mussels (Mytilus edulis) accumulate and biotransform arsenic (As) to a larger variety of arsenicals than most seafood. Eight volunteers ingested a test meal consisting of 150g blue mussel (680μg As), followed by 72h with an identical, low As controlled diet and full urine sampling. We provide...... a complete speciation, with individual patterns, of urinary As excretion. Total As (tAs) urinary excretion was 328±47μg, whereof arsenobetaine (AB) and dimethylarsinate (DMA) accounted for 66% and 21%, respectively. Fifteen minor urinary arsenicals were quantified with inductively coupled plasma mass...... spectrometry (ICPMS) coupled to reverse-phase, anion and cation-exchange high performance liquid chromatography (HPLC). Thio-arsenicals and non-thio minor arsenicals (including inorganic As (iAs) and methylarsonate (MA)) contributed 10% and 7% of the total sum of species excretion, respectively, but there were...

  18. Effect of seawater desalination and oil pollution on the lipid composition of blue mussels Mytilus edulis L. from the White Sea.

    Science.gov (United States)

    Fokina, N N; Bakhmet, I N; Shklyarevich, G A; Nemova, N N

    2014-12-01

    A study on the effect oil pollution under normal and reduced salinity had on blue mussels Mytilus edulis L. from the White Sea in an aquarium-based experiment and in the natural habitat revealed a change in gill total lipids as a compensatory response. The cholesterol concentration and the cholesterol/phospholipids ratio in gills were found to reflect the impact of the environmental factors (oil pollution and desalination), and evidence adaptive changes in the cell membrane structure. An elevated content of storage lipids (chiefly triacylglycerols) in the mussels in the aquarium experiment indicates, first of all, the uptake and accumulation of oil products in gill cells under both normal and reduced seawater salinity, while high triacylglycerols level in gill littoral mussels from 'control' biotope in the Gulf of Kandalaksha is primarily associated with the mussel׳s pre-spawning period.

  19. Comparative study of predatory responses in blue mussels (Mytilus edulis L.) produced in suspended long line cultures or collected from natural bottom mussel beds

    DEFF Research Database (Denmark)

    Christensen, Helle Torp; Dolmer, Per; Petersen, Jens Kjerulf

    2011-01-01

    Blue mussels (Mytilus edulis L.) are a valuable resource for commercial shellfish production and may also have uses as a tool in habitat improvement, because mussel beds can increase habitat diversity and complexity. A prerequisite for both commercial mussel production and habitat improvement...... is the availability of seed mussels collected with minimum impact on the benthic ecosystem. To examine whether mussels collected in suspended cultures can be used for bottom culture production and as tool in habitat improvement, the differences in predatory defence responses between suspended and bottom mussels...... originated from suspended cultures had a higher length increment and lower mortality when compared to bottom mussels. It is concluded that suspended mussels potentially are an alternative resource to bottom culture and can be used in habitat improvement of mussel beds, but that the use of suspended mussels...

  20. Interactive effects of n-TiO2 and 2,3,7,8-TCDD on the marine bivalve Mytilus galloprovincialis.

    Science.gov (United States)

    Canesi, Laura; Frenzilli, Giada; Balbi, Teresa; Bernardeschi, Margherita; Ciacci, Caterina; Corsolini, Simonetta; Della Torre, Camilla; Fabbri, Rita; Faleri, Claudia; Focardi, Silvano; Guidi, Patrizia; Kočan, Anton; Marcomini, Antonio; Mariottini, Michela; Nigro, Marco; Pozo-Gallardo, Karla; Rocco, Lucia; Scarcelli, Vittoria; Smerilli, Arianna; Corsi, Ilaria

    2014-08-01

    Despite the growing concern over the potential biological impact of nanoparticles (NPs) in the aquatic environment, little is known about their interactions with other pollutants. The bivalve Mytilus sp, largely utilized as a sentinel for marine contamination, has been shown to represent a significant target for different types of NP, including n-TiO2, one of the most widespread in use. In this work, the possible interactive effects of n-TiO2 and 2,3,7,8-TCDD, chosen as models of NP and organic contaminant, respectively, were investigated in Mytilus galloprovincialis. In vitro experiments with n-TiO2 and TCDD, alone and in combination, were carried out in different conditions (concentrations and times of exposure), depending on the target (hemocytes, gill cells and biopsies) and the endpoint measured. Mussels were also exposed in vivo to n-TiO2 (100 μg L(-1)) or to TCDD (0.25 μg L(-1)), alone and in combination, for 96 h. A wide range of biomarkers, from molecular to tissue level, were measured: lysosomal membrane stability and phagocytosis in hemocytes, ATP-binding cassette efflux transporters in gills (gene transcription and efflux activity), several biomarkers of genotoxicity in gill and digestive cells (DNA damage, random amplified polymorphic DNA-RAPD changes), lysosomal biomarkers and transcription of selected genes in the digestive gland. The results demonstrate that n-TiO2 and TCDD can exert synergistic or antagonistic effects, depending on experimental condition, cell/tissue and type of measured response. Some of these interactions may result from a significant increase in TCDD accumulation in whole mussel organisms in the presence of n-TiO2, indicating a Trojan horse effect. The results represent the most extensive data obtained so far on the sub-lethal effects of NPs and organic contaminants in aquatic organisms. Moreover, these data extend the knowledge on the molecular and cellular targets of NPs in bivalves.

  1. Oxygen isotope ratios in the shell of Mytilus edulis: archives of glacier meltwater in Greenland?

    DEFF Research Database (Denmark)

    Versteegh, E. A. A.; Blicher, Martin E.; Mortensen, J.

    2012-01-01

    these variations, because it precipitates its shell calcite in oxygen isotopic equilibrium with ambient seawater. As M. edulis shells are known to occur in raised shorelines and kitchen middens from previous Holocene warm periods, this species may be ideal in reconstructing past meltwater dynamics. We investigate...... raised shorelines and kitchen middens from prehistoric settlements in Greenland....

  2. Direct observation of a central bare zone in a native thick filament isolated from the anterior byssus retractor muscle of Mytilus edulis using fluorescent ATP analogue.

    Science.gov (United States)

    Oiwa, K; Yamaga, T; Yamada, A

    1998-04-01

    To investigate the existence of a central bare zone in native thick filaments isolated from the anterior byssus retractor muscle (ABRM) of blue mussels (Mytilus edulis), the filaments were observed by fluorescence and dark-field microscopy after being incubated in the presence of Ca2+ with the fluorescent ATP analogue, Cy3-EDA-ATP. Filaments appeared under dark-field illumination as thin rods with tapered ends of length 5-30 microm. Fluorescence microscopy revealed that Cy3-EDA-ATP was bound to these filaments, except near their center. Although the boundary between this central non-fluorescent zone and fluorescent regions was not clearly defined, there was a trend for the width of the central non-fluorescent zone to increase with thick filament length (correlation coefficient = 0.45; n = 142). When Cy3-EDA-nucleotides bound to thick filaments were displaced by excess ATP, fluorescent images disappeared with a rate constant of 0. 024 s-1, close to the turnover rate of Cy3-EDA-ATP by myosin on the native thick filaments. These results indicate that each native thick filament isolated from the ABRM has a central bare zone, but its boundary was not sharply resolved.

  3. Content analysis of heavy metals in Mytilus edulis from the special marine reserve of ShengSi MaAn Islands%嵊泗马鞍列岛国家级海洋特别保护区海域养殖紫贻贝(Mytilus edulis)重金属含量分析

    Institute of Scientific and Technical Information of China (English)

    胡益峰; 蒋红

    2012-01-01

    根据2005--2011年嵊泗马鞍列岛海洋特别保护区海域养殖紫贻贝(Mytilus edulis)重金属的监测结果,对贻贝生物体的汞(Hg)、砷(As)、铜(Cu)、铅(Pb)、镉(Cd)5种重金属元素的含量进行分析,对贻贝的质量安全进行了评价。结果表明:(1)贻贝体内重金属含量大小顺序为Cu〉Cd〉As〉Pb〉Hg,Cu含量最高,而Pb和cd含量超一类海洋生物质量标准;(2)贻贝体内As和cd含量已超过中国农业行业标准“无公害食品:水产品有毒有害物质限量”标准,应引起政府部门的高度重视。%According to the monitoring data of heavy metals (Hg, As , Cu , Pb and Cd) in Mytilus edulis from 2005 to 2011 in the sea areas of the special marine reserve of ShengSi MaAn Islands, we evaluated the safety and the healthy quality of Mytilus edulis. The results were obtained as follows: ( 1 ) The sequence of heavy metal contents in Mytilus edulis was Cu 〉 Cd 〉 As 〉 Pb 〉 Hg, the content of Cu was highest, and the contents of Pb and Cd belonged to the first class of marine biological quality standard. (2) The contents of As and Cd in Mytilus edulis highly exceeded the limit standard of "non - environmental pollution food, the limit for the deleterious matters in the aquatic product". The government should pay high attention to this issue.

  4. The effect of lanthanum on the nexus of the anterior byssus retractor muscle of Mytilus edulis L.

    Science.gov (United States)

    Brink, P R; Kensler, R W; Dewey, M M

    1979-01-01

    The nexus of the anterior byssus retractor muscle (ABRM) of Mytilus has been observed with freeze-fracture techniques. Pits appear in the EF face and particles in the PF face, designating it as an A-type nexus. Under control conditions (lanthanum-free) the center-to-center spacing of pits and particles ranged from 14.0 nm to 15.5 nm. When lanthanum chloride (5 mM) was used in incubation media before fixation and glycerination, marked changes in the nexal membrane were observed. These changes involved close packing and long-range ordering of pits in the EF face, as shown by optical diffraction. In the presence of lanthanum the center-to-center spacing of the pits was 11.7 nm, while the particles remained at a spacing of 15.0 nm. From this we conclude that specific agents can alter the array of pits and particles in a nexus (gap junction).

  5. Comparison of intermittent and continuous exposures to inorganic mercury in the mussel, Mytilus edulis: accumulation and sub-lethal physiological effects.

    Science.gov (United States)

    Amachree, Dokuboba; Moody, A John; Handy, Richard D

    2014-11-01

    Aquatic organisms are often subject to intermittent exposure to pollutants in real ecosystems. This study aimed to compare mercury accumulation and the physiological responses of mussels, Mytilus edulis during continuous and intermittent exposure to the metal. Mussels were treated in a semi-static, triplicated design to either a control (no added Hg) or 50 µg l(-1) Hg as HgCl2 in continuous (daily) or intermittent (2 day exposure, 2 days in clean seawater alternately) exposure for 14 days. A time-dependent increase in Hg accumulation was observed in the continuous exposure, while the intermittent treatment showed step-wise changes in Hg concentrations with the exposure profile, especially in the gills. At the end of the experiment, tissue Hg concentrations were significantly increased in the continuous compared to the intermittent exposure for digestive gland (4 fold), gonad and remaining soft tissue (>2 fold), but not for the gill and adductor muscle. There was no observed oxidative damage at the end of the experiment as measured by the thiobarbituric acid reactive substances (TBARS) concentrations in tissues from all treatments. However, total glutathione was significantly decreased in the gill and digestive gland of both the continuous and intermittent exposure by the end of the experiment. The neutral red retention ability of the haemocytes was not affected, but total haemocyte counts were significantly decreased (<2 fold) in the intermittent compared to the continuous exposure. Histopathological examinations showed less pathology in the gill, but more inflammation in the digestive gland of mussels for the intermittent compared to the continuous exposure. Overall, the results showed that Hg accumulation from intermittent exposure was less than that of the continuous exposure regime, but the sub-lethal responses are sometimes more severe than expected in the former.

  6. Application of SSH and a macroarray to investigate altered gene expression in Mytilus edulis in response to exposure to benzo[a]pyrene.

    Science.gov (United States)

    Brown, M; Davies, I M; Moffat, C F; Craft, J A

    2006-07-01

    The lack of genomic resources for aquatic invertebrates restricts their use as sentinel species in coastal environments. It is known that where genomic data are not available, suppression subtractive hybridisation (SSH) can generate cDNA libraries representative of pollutant-responsive gene transcription in aquatic vertebrates. To assess whether the approach was equally suited to aquatic invertebrates, altered gene expression in digestive gland of the mussel, Mytilus edulis, in response to exposure to benzo[a]pyrene (BaP) (1 mg/l) was investigated with SSH and a nylon macroarray. Screening of the subtracted libraries showed 112/250 up-regulated and 25/55 down-regulated clones were positive for differential expression and characterisation of these identified 87 with unique sequence suitable for array on a nylon membrane. The transcripts isolated were from a diverse range of genes involved in general stress, oxidative stress, cell adhesion, transcriptional and translational regulation, transport mechanisms, energy metabolism, cell metabolism, lipid metabolism, protein turnover and activation, lysosomal activity and 22 cryptic clones. Subsequent use of the clones in macroarray format to analyse expression of BaP-responsive genes (0 vs 4 day exposed) showed 0-100-fold increased levels of the forward-subtracted probes and between 0 and 0.1-fold down-regulation of the reverse-subtracted probes. Only 15% of the clones showed less than 2-fold change in expression. The gene ontology of the transcripts isolated demonstrates that BaP elicits a multitude of responses with a major feature being disruption of cellular redox status. The results indicate that the use of SSH and a macroarray is a robust method to discover novel pollutant-responsive genes in aquatic invertebrates.

  7. Linking genotoxic responses with cytotoxic and behavioural or physiological consequences: differential sensitivity of echinoderms (Asterias rubens) and marine molluscs (Mytilus edulis).

    Science.gov (United States)

    Canty, Martin N; Hutchinson, Thomas H; Brown, Rebecca J; Jones, Malcolm B; Jha, Awadhesh N

    2009-08-13

    Integrated laboratory studies addressed multiple biomarker responses in the sea star (Asterias rubens) and the blue mussel (Mytilus edulis) exposed to a range of concentrations of direct and indirect acting genotoxins: methyl methane sulfonate (MMS) and cyclophosphamide (CP; an environmentally relevant anti-cancer pharmaceutical), respectively, in order to determine if the expressed genotoxicity has knock-on effects at the higher levels of biological organisation. The experimental design aimed to concurrently evaluate biomarkers of behavioural and physiological conditions (i.e. 'righting time' and 'clearance rate' for sea stars and mussels, respectively) in addition to cytotoxicity (neutral red retention assay), induction of micronuclei (Mn) and DNA strand breaks (as determined by the Comet assay). The protocol also included the determination of the maximum tolerated concentration (MTC), prior to genotoxic evaluation. The 3d MTC, as determined by the survival of the organisms, showed sea stars to be more sensitive than mussels to MMS (18 and 32 mg L(-1), respectively) and CP (56 and 180 mg L(-1), respectively). For both species and chemicals, cytotoxicity was not found to be significantly different compared to controls. Apart from the MMS exposure to sea stars (which showed 100% mortality at higher concentrations after 5d exposure), clear dose-response relationships were observed for both genotoxicity endpoints in each species. Following exposure to CP, good correlations were also found between the behavioural and physiological responses and genetic damage in each species (sea stars-MN vs. RT: R=0.73; Comet vs. RT: R=0.91; mussels-MN vs. CR: R=0.69; Comet vs. CR: R=0.72). This integrated approach, applying non-invasive assays to simultaneously determine the responses at different levels of biological organisation, indicates the potential value of behavioural and physiological measures in determining the toxicity of chemicals to marine organisms and highlights also

  8. Metabolic Effects in the Bivalve Perna perna and Mytilus galloprovincialis: Impact on the Environment due to Contamination by Copper

    Directory of Open Access Journals (Sweden)

    Mohamed Brahim Errahmani

    2014-01-01

    Full Text Available This work presents the study of the effects of acute exposure to various concentrations of copper from 0.03 to 0.59 μmol·L−1 on the metabolic activities (nitrogen and phosphorus, protein levels, catalase (CAT enzyme activities, and the biological response malondialdehyde (MDA in the mollusks Perna perna and Mytilus galloprovincialis. The concentrations above 0.88 μmol·L−1 have proven to be lethal to P. perna. The results show slight disturbances of metabolism as a result of pollutant and a significant correlation between metal contamination and ammonia nitrogen levels, resulting in an increase in the latter after 48 h of M. galloprovincialis exposure to 0.59 μmol·L−1 of copper concentrations. CAT was rapidly induced even by low concentrations of copper; MDA was increased only with low concentrations of copper in P. perna.

  9. Location of Saccharides on the Gamete of Mytilus edulis Linnaeus%紫贻贝配子细胞表面糖基的定位研究

    Institute of Scientific and Technical Information of China (English)

    刘慧慧; 李太武; 苏秀榕

    2011-01-01

    细胞表面糖蛋白中糖的特性对于细胞的相互识别起重要作用,配子细胞表面糖配基的差异恰恰体现不同物种间受精作用的特异性,本研究分别选用可以特异性结合半乳糖、葡萄糖、甘露糖、岩藻糖的FITC标记凝集素,对紫贻贝配子细胞中对应的糖进行研究。结果显示,4种糖在卵细胞边缘的标记特征不明显,仅半乳糖和葡萄糖在一些卵细胞边缘有区域性分布,但在细胞质区,这4种糖均有少量分布;半乳糖和岩藻糖在贻贝的精巢的精细胞和成熟精子区为较均匀的弱阳性标记,甘露糖仅在输精小管边缘有分布,葡萄糖的含量相对较多,但也只是在输精小管边缘以及成熟精子区有一定的标记。上述结果表明,紫贻贝配子细胞表面不同糖基的分布和含量存在一定的差异,造成配子间起到识别作用的糖蛋白组成和结构不同,决定了紫贻贝配子识别的特异性。%The saccharides of glycoprotein on cell are important for cellular recognition.The differences of sugar ligands on gamete decide specificity of fertilization between interspecies.We selected 4 FITC labeled lectin(bound to mannose,galactose,glucose,fucose) to investgate the saccharides on gamete of Mytilus edulis.Galactose and glucose were labeled regionally on the border of egg,but mannose,galactose,glucose and fucose distributed slightly in cytoplasm.There were weak marks of galactose and fucose in sperm cell and mature sperm.Mannose and glucose distributed the border of spermi duct,but glucose marked apparently in mature sperm.The results showed that the distribution and cotent of diverse saccharides were different,and the construction and structure of glycoprotein were also different.These characters decided the specificity of gamete recognition in M.edulis.

  10. The 'catch' mechanism in molluscan muscle: an electron microscopy study of freeze-substituted anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Bennett, P M; Elliott, A

    1989-08-01

    A method for quick-freezing muscles while observing their mechanical properties until the moment of freezing is described. This method was used to freeze the anterior byssus retractor muscle (ABRM) of Mytilus edulis. Intact muscle in the presence of sucrose as a cryoprotectant was freeze-substituted in acetone, fixed and embedded for electron microscopy. ABRM was frozen in a number of mechanical states including 'catch', the state of high passive tension particularly associated with some molluscan muscles. Transverse sections were examined to determine the distribution of filaments in the muscle cells. In the relaxed muscle thick and thin filaments are fairly randomly distributed. Groups of thin filaments and of thick filaments are often seen, and there is no obvious association between the two types of filaments. In contrast, in rigor muscles, both glycerol-extracted and intact, most of the thin filaments were found to lie in rings or rosettes around the thick filaments. In some places bridges between thick and thin filaments could be distinguished. In actively contracting muscle (phasic contraction) the appearance is intermediate between that of the relaxed and rigor muscles. Many thick filaments are surrounded by rosettes of thin filaments but many of the thin filaments are grouped and have no connections with thick filaments. The 'catch' state, left after a period of tonic contraction, is similar in its distribution of thick and thin filaments to the active state, many of the thin filaments lying between the thick. Frequently thick and thin filaments seem to be closer together than in other states of the muscle where a pronounced exclusion zone is present around the thick filaments. There is no evidence for association between the thick filaments. The different distribution of thin filaments in the different states is consistent with the previously described X-ray diffraction data if it is assumed that most of the contribution to the equatorial reflection at 12

  11. Conditions of Mytilus edulis extracellular body fluids and shell composition in a pH-treatment experiment: Acid-base status, trace elements and δ11B

    Science.gov (United States)

    Heinemann, Agnes; Fietzke, Jan; Melzner, Frank; BöHm, Florian; Thomsen, JöRn; Garbe-SchöNberg, Dieter; Eisenhauer, Anton

    2012-01-01

    Mytilus edulis were cultured for 3 months under six different seawater pCO2 levels ranging from 380 to 4000 μatm. Specimen were taken from Kiel Fjord (Western Baltic Sea, Germany) which is a habitat with high and variable seawater pCO2 and related shifts in carbonate system speciation (e.g., low pH and low CaCO3 saturation state). Hemolymph (HL) and extrapallial fluid (EPF) samples were analyzed for pH and total dissolved inorganic carbon (CT) to calculate pCO2 and [HCO3-]. A second experiment was conducted for 2 months with three different pCO2 levels (380, 1400 and 4000 μatm). Boron isotopes (δ11B) were investigated by LA-MC-ICP-MS (Laser Ablation-Multicollector-Inductively Coupled Plasma-Mass Spectrometry) in shell portions precipitated during experimental treatment time. Additionally, elemental ratios (B/Ca, Mg/Ca and Sr/Ca) in the EPF of specimen from the second experiment were measured via ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry). Extracellular pH was not significantly different in HL and EPF but systematically lower than ambient water pH. This is due to high extracellular pCO2 values, a prerequisite for metabolic CO2 excretion. No accumulation of extracellular [HCO3-] was measured. Elemental ratios (B/Ca, Mg/Ca and Sr/Ca) in the EPF increased slightly with pH which is in accordance with increasing growth and calcification rates at higher seawater pH values. Boron isotope ratios were highly variable between different individuals but also within single shells. This corresponds to a high individual variability in fluid B/Ca ratios and may be due to high boron concentrations in the organic parts of the shell. The mean δ11B value shows no trend with pH but appears to represent internal pH (EPF) rather than ambient water pH.

  12. Comparative feeding on chlorophyll - rich versus remaining organic matter in bivalve shellfish

    NARCIS (Netherlands)

    Hawkins, A.; Pascoe, P.L.; Parry, H.; Brinsley, M.; Cacciatore, F.; Black, K.; Fang, J.; Smaal, A.C.

    2013-01-01

    Filter feeding was compared in the blue mussel Mytilus edulis, Mediterranean mussel Mytilus galloprovincialis, Pacific oyster Crassostrea gigas, Chinese pleated oyster Crassostrea plicatula, Chinese scallop Chlamys farreri,Manila clam Tapes phillipinarum, razor clam Sinonvacula constricta, and blood

  13. Trace elements in the organs and tissues of bivalves in the northwestern Black Sea

    Energy Technology Data Exchange (ETDEWEB)

    Petkevich, T.A.; Gorbyleva, T.P.

    1979-01-01

    An investigation was made of the distribution of 16 trace elements (copper, manganese, iron, aluminum, zinc, barium, strontium, lead, tin, silver, vanadium, nickel, chromium, lithium, titanium and cobalt) in the organs and tissues of bivalves in the northwestern Black Sea and in the Sukhoy and Berezanskiy estuaries. These elements were selected because they are constituents of enzymes, vitamins and other metal-protein complexes, or activate enzymes, and are involved in redox reactions in the transfer of electrons and hydrogen. We investigated mussels (Mytilus galloprovincialis), soft-shell clams (Mya arenaria) and oysters (Ostrea edulis), analyzing the mantle, gills, liver, gonads, adductor muscles, foot and shell, and also in Mya the siphon and its outer epithelial layer, the cuticle. Similar data on Anodonta, a freshwater bivalve of the Dniester estuary, were used for comparison.

  14. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

    Science.gov (United States)

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-21

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

  15. Extraction and Analysis of Polyenoic Fatty Acyl Ethyl Esters and Taurine in Mytilus edulis%紫贻贝多烯脂肪酸乙酯及牛磺酸的提取与分析

    Institute of Scientific and Technical Information of China (English)

    张翼; 穆军; 吕红丽; 顾晓洁; 史继诚

    2011-01-01

    For comprehensive utilization of the functional health products from the low-value shells, the poly-unsaturated fatty acyl ethyl esters in Mytilus edulis were extracted by Soxhlet/supersonic extraction and urea complexation, and taurine in the residue after the fatty extraction was extracted by hot water digestion and ionexchange chromatography. The contents of eicosapentaenoic acyl ether ester (EPA-E) and docosahexaenoic acyl ethyl esters (DHA-E) in the product were analyzed by HPLC-DAD. By thin layer chromatography and spectrophotometry, taurine in the crude product was qualitatively and quantitatively analyzed, respectively.The results show that the Mytilus edulis contains rich EPA, DHA and taurine and it is an expectable resource of high-value functional health food.%为综合开发利用低价值贝类中的功能保健品成分,利用索氏/超声提取、尿素包合法提取了紫贻贝中的多烯脂肪酸乙酯,对提油后的残渣利用热水提取、离子交换层析富集的方法提取了其中的牛磺酸,利用高效液相色谱-二极管阵列检测器(HPLC-DAD)分析测定了产品中二十碳五烯酸乙酯(EPA-E)、二十二碳六烯酸乙酯(DHA-E)的含量,利用薄层色谱法、吸光光度法定性定量测定了产品中的牛磺酸,结果显示紫贻贝中含有相当量的多烯脂肪酸乙酯及牛磺酸成分,有望作为高价值功能保健食品的来源.

  16. Mussel shells of Mytilus edulis as bioarchives of the rare earth elements and yttrium distribution in seawater and the potential impact of pH and temperature on the partitioning behaviour

    Directory of Open Access Journals (Sweden)

    A. Ponnurangam

    2015-09-01

    Full Text Available Mussel shells are potential bioarchives of proxies for changes of the physico-chemical conditions in the bivalve's habitat. One such proxy is the distribution of the Rare Earths and Yttrium (REY in seawater, as REY speciation in seawater is sensitive to pH and temperature variations, due to the impact of these parameters on the activity of CO32− in seawater. We present a new protocol for sample preparation and determination of REY concentrations in bivalve shells, that includes sample treatment with NaOCl followed by REY separation and preconcentration. The data obtained was further used to calculate REY partition coefficients between shells of M. edulis and ambient seawater, and acquired results were then used in the investigation of the potential effects of pH and temperature on REY partitioning. Shells of M. edulis mussels from the North Sea show consistent shale-normalized ("SN" REY patterns that increase from the light REY to the middle REY and decrease from the middle REY to the heavy REY. Despite being different to the general seawater REYSN pattern, the shells still display distinct REY features of seawater such as a negative CeSN anomaly and small positive YSN and GdSN anomalies. Apparent partition coefficients for the REY between the shell and seawater (appDREYshell/seawater are low and decrease strongly from the light REY (4.04 for La to the heavy REY (0.34 for Lu. However, assuming that only the free REY3+ are incorporated into the shell, appDREY3+shell/seawater values are higher and rather similar for all REY (102.46 for La; 113.44 for Lu, but show a slight maximum at Tb (199.18. Although the impact of vital effects i.e. REY speciation in a mussel's extrapallial fluid from which the carbonate minerals precipitate, cannot be quantified yet, it appears that M. edulis shells are bioarchives of some REY features of seawater. We modelled the REYSN patterns of a hypothetical mussel shell at pH 8.2 and 7.6 and at temperatures of 25

  17. Mussel shells of Mytilus edulis as bioarchives of the rare earth elements and yttrium distribution in seawater and the potential impact of pH and temperature on the partitioning behaviour

    Science.gov (United States)

    Ponnurangam, A.; Bau, M.; Brenner, M.; Koschinsky, A.

    2015-09-01

    Mussel shells are potential bioarchives of proxies for changes of the physico-chemical conditions in the bivalve's habitat. One such proxy is the distribution of the Rare Earths and Yttrium (REY) in seawater, as REY speciation in seawater is sensitive to pH and temperature variations, due to the impact of these parameters on the activity of CO32- in seawater. We present a new protocol for sample preparation and determination of REY concentrations in bivalve shells, that includes sample treatment with NaOCl followed by REY separation and preconcentration. The data obtained was further used to calculate REY partition coefficients between shells of M. edulis and ambient seawater, and acquired results were then used in the investigation of the potential effects of pH and temperature on REY partitioning. Shells of M. edulis mussels from the North Sea show consistent shale-normalized ("SN") REY patterns that increase from the light REY to the middle REY and decrease from the middle REY to the heavy REY. Despite being different to the general seawater REYSN pattern, the shells still display distinct REY features of seawater such as a negative CeSN anomaly and small positive YSN and GdSN anomalies. Apparent partition coefficients for the REY between the shell and seawater (appDREYshell/seawater) are low and decrease strongly from the light REY (4.04 for La) to the heavy REY (0.34 for Lu). However, assuming that only the free REY3+ are incorporated into the shell, appDREY3+shell/seawater values are higher and rather similar for all REY (102.46 for La; 113.44 for Lu), but show a slight maximum at Tb (199.18). Although the impact of vital effects i.e. REY speciation in a mussel's extrapallial fluid from which the carbonate minerals precipitate, cannot be quantified yet, it appears that M. edulis shells are bioarchives of some REY features of seawater. We modelled the REYSN patterns of a hypothetical mussel shell at pH 8.2 and 7.6 and at temperatures of 25 and 5

  18. Growth of mussels Mytilus edulis at algal (Rhodomonas salina) concentrations below and above saturation level for reduced filtration rate

    DEFF Research Database (Denmark)

    Riisgård, Hans Ulrik; Pleissner, Daniel; Larsen, Poul Scheel;

    2013-01-01

    to about 1.5 % day-1. Below Csat on the other hand, measured μ values increased linearly with increasing algal concentration which was in good agreement with an earlier advanced bioenergetic growth model. The overall functional response of M. edulis resembles a Type I in terms of gross ingestion...

  19. Determination of the recovery efficiency of cryptosporidium oocysts and giardia cysts from seeded bivalve mollusks.

    Science.gov (United States)

    Schets, Franciska M; van den Berg, Harold H J L; de Roda Husman, Ana Maria

    2013-01-01

    The intestinal parasites Cryptosporidium and Giardia are transmitted by water and food and cause human gastroenteritis. Filter-feeding bivalve mollusks, such as oysters and mussels, filter large volumes of water and thus concentrate such pathogens, which makes these bivalves potential vectors of disease. To assess the risk of infection from consumption of contaminated bivalves, parasite numbers and parasite recovery data are required. A modified immunomagnetic separation (IMS) procedure was used to determine Cryptosporidium oocyst and Giardia cyst numbers in individually homogenized oysters (Crassostrea gigas) and mussels (Mytilus edulis). About 12% of the commercial bivalves were positive, with low (oo)cyst numbers per specimen. The recovery efficiency of the IMS procedure was systematically evaluated. Experiments included seeding of homogenized bivalves and whole animals with 100 to 1,000 (oo)cysts. Both seeding procedures yielded highly variable recovery rates. Median Cryptosporidium recoveries were 7.9 to 21% in oysters and 62% in mussels. Median Giardia recoveries were 10 to 25% in oysters and 110% in mussels. Giardia recovery was significantly higher than Cryptosporidium recovery. (Oo)cysts were less efficiently recovered from seeded whole animals than from seeded homogenates, with median Cryptosporidium recoveries of 5.3% in oysters and 45% in mussels and median Giardia recoveries of 4.0% in oysters and 82% in mussels. Both bivalve homogenate seeding and whole animal seeding yielded higher (oo)cyst recovery in mussels than in oysters, likely because of the presence of less shellfish tissue in IMS when analyzing the smaller mussels compared with the larger oysters, resulting in more efficient (oo)cyst extraction. The data generated in this study may be used in the quantitative assessment of the risk of infection with Cryptosporidium or Giardia associated with the consumption of raw bivalve mollusks. This information may be used for making risk management

  20. The multi-xenobiotic resistance (MXR) efflux activity in hemocytes of Mytilus edulis is mediated by an ATP binding cassette transporter of class C (ABCC) principally inducible in eosinophilic granulocytes.

    Science.gov (United States)

    Rioult, Damien; Pasquier, Jennifer; Boulangé-Lecomte, Céline; Poret, Agnès; Abbas, Imane; Marin, Matthieu; Minier, Christophe; Le Foll, Frank

    2014-08-01

    In marine and estuarine species, immunotoxic and/or immunomodulatory mechanisms are the crossroad of interactions between xenobiotics, microorganisms and physicochemical variations of the environment. In mussels, immunity relies exclusively on innate responses carried out by cells collectively called hemocytes and found in the open hemolymphatic circulatory system of these organisms. However, hemocytes do not form a homogenous population of immune cells since distinct subtypes of mussel blood cells can be distinguished by cytochemistry, flow cytometry or cell motility analysis. Previous studies have also shown that these cells are able to efflux xenobiotics by means of ATP binding cassette (ABC) transporter activities conferring a multixenobiotic resistance (MXR) phenotype. ABC transporters corresponding to vertebrate class B/P-glycoprotein (P-gp) and to class C/multidrug resistance related protein (MRP) are characterized in Mytilidae. Herein, we have investigated the relative contributions of ABCB- and ABCC-mediated efflux within the different hemocyte subpopulations of Mytilus edulis mussels, collected from areas differentially impacted by chemical contaminants in Normandy (France). RT-PCR analyses provide evidence for the presence of ABCB and ABCC transporters transcripts in hemocytes. Immunodetection of ABCB/P-gp with the monoclonal antibody UIC2 in living hemocytes revealed that expression was restricted to granular structures of spread cells. Efflux transporter activities, with calcein-AM as fluorescent probe, were measured by combining flow cytometry to accurate Coulter cell size measurements in order to get a cell-volume normalized fluorescence concentration. In these conditions, basal fluorescence levels were higher in hemocytes originating from Yport (control site) than in cells collected from the harbor of Le Havre, where mussels are more exposed to with persistent pollutants. By using specific ABCB/P-gp (verapamil, PSC833, zosuquidar) and ABCC/MRP (MK

  1. Changes in sarcoplasmic metabolite concentrations and pH associated with the catch contraction and relaxation of the anterior byssus retractor muscle of Mytilus edulis measured by phosphorus-31 nuclear magnetic resonance.

    Science.gov (United States)

    Ishii, N; Mitsumori, F; Takahashi, K

    1991-06-01

    The sarcoplasmic concentrations of phosphorus metabolites and pH (pHin) were measured in the anterior byssus retractor muscle (ABRM) of Mytilus edulis by 31P nuclear magnetic resonance spectroscopy. During an active contraction induced by 10(-3) acetylcholine, the concentration of arginine phosphate ([Arg-P]in) decreased from the resting value of 7.47 +/- 0.26 (mean +/- SE, n = 8) to 6.67 +/- 0.29 (n = 6) mumol g-1, and that of inorganic phosphate (Pi) consistently increased from 0.84 +/- 0.06 (n = 7) to 1.61 +/- 0.12 (n = 5) mumol g-1. In the 'catch' state following the active contraction, these concentrations were close to their resting levels, indicating that the catch is an inactive state. 5-hydroxytryptamine caused a rapid relaxation of the catch, which was associated with a slight decrease in [Arg-P]in and an increase in pHin by ca 0.2 units. The sarcoplasmic concentration of ATP (mean, 1.6 mumol g-1) did not change throughout the contraction-relaxation cycle.

  2. Carbachol and KCl-induced changes in intracellular free calcium concentration in isolated, fura-2 loaded smooth-muscle cells from the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Ishii, N; Simpson, A W; Ashley, C C

    1988-06-16

    Intracellular free calcium concentration [( Ca2+]1) was measured in suspensions of fura-2 loaded smooth-muscle cells isolated from the anterior byssus retractor muscle of Mytilus edulis. Successive application of 5mM carbachol (CCh) and 100mM KCl to the cells transiently elevated [Ca2+]1 from the resting value of 124 +/- 4.5nM (mean +/- S.E., n = 14) to 295 +/- 15.3 and 383 +/- 20.5 nM, respectively. The response to CCh was concentration-dependent with an ED50 of 10(-5) M. Under the microscope, 67 +/- 3.0 and 83 +/- 1.3 % of fura-2 loaded cells contracted on the addition of 5mM CCh and 100mM KCl, respectively. In Ca2+ -free sea water, the CCh induced change in [Ca2+]1 was partially suppressed whereas that induced by KCl was completely abolished, suggesting an agonist-evoked release of stored Ca2+.

  3. Total and methyl-mercury content in bivalves, Mytilus galloprovincialis Lamarck and Ostrea edulis Linnaeus: relationship of biochemical composition and body size

    Energy Technology Data Exchange (ETDEWEB)

    Najdek, M.; Sapunar, J.

    1987-07-01

    Mussels and oysters are of interest to pollution ecologists because they are widely distributed, suspension feeding invertebrates and are likely to accumulate pollutants from their environment (Goldberg 1975). Many authors have estimated the relation between the concentration of metals in the flesh and various biotic and abiotic parameters. Body mass (estimated in dry weight) is evidently an important factor governing the uptake of metals by these organisms. The highest concentrations of certain metals were often found in the smallest individuals. The relation between metal content and body size can best be described using Boyden's model which is useful for quantifying any physiological activities in relation to the dry weight of the specimens. In the present paper the authors describe the investigation into the relationship between total and methyl-mercury content and body mass in mussels and oysters.

  4. Toxic dinoflagellates and Vibrio spp. act independently in bivalve larvae.

    Science.gov (United States)

    De Rijcke, M; Van Acker, E; Nevejan, N; De Schamphelaere, K A C; Janssen, C R

    2016-10-01

    Harmful algal blooms (HABs) and marine pathogens - like Vibrio spp. - are increasingly common due to climate change. These stressors affect the growth, viability and development of bivalve larvae. Little is known, however, about the potential for interactions between these two concurrent stressors. While some mixed exposures have been performed with adult bivalves, no such work has been done with larvae which are generally more sensitive. This study examines whether dinoflagellates and bacteria may interactively affect the viability and immunological resilience of blue mussel Mytilus edulis larvae. Embryos were exposed to environmentally relevant concentrations (100, 500, 2500 & 12,500 cells ml(-1)) of a dinoflagellate (Alexandrium minutum, Alexandrium ostenfeldii, Karenia mikimotoi, Protoceratium reticulatum, Prorocentrum cordatum, P. lima or P. micans), a known pathogen (Vibrio coralliilyticus/neptunius-like isolate or Vibrio splendidus; 10(5) CFU ml(-1)), or both. After five days of exposure, significant (p larval viability and larval development were found for all dinoflagellates (except P. cordatum) and V. splendidus. Yet, despite the individual effect of each stressor, no significant interactions were found between the pathogens and harmful algae. The larval viability and the phenoloxidase innate immune system responded independently to each stressor. This independence may be related to a differential timing of the effects of HABs and pathogens.

  5. Bivalve aquaculture-environment interactions in the context of climate change.

    Science.gov (United States)

    Filgueira, Ramón; Guyondet, Thomas; Comeau, Luc A; Tremblay, Réjean

    2016-12-01

    Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom-up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve-phytoplankton trophic interaction, which can range from a bottom-up control triggered by ammonia excretion to a top-down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top-down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is

  6. Bioaccumulation of heavy metals by bivalves from lim fjord (North Adriatic Sea)

    Energy Technology Data Exchange (ETDEWEB)

    Martincic, D.; Nurnberg, H.W.; Stoeppler, M.; Branica, M.

    1984-08-01

    The accumulation of trace metals (Zn, Cd, Pb, and Cu) by two bivalves (Mytilus galloprovincialis and Ostrea edulis) growing at the same station and therefore under the same physicochemical conditions was studied. The oysters were more effective bioaccumulators for zinc, cadmium, lead and copper than the mussels. Oysters accumulate about 10-fold higher quantities of zinc than mussels, 16-fold higher for copper, 3-fold higher cadmium, and 2-fold higher lead concentrations. The observed differences in the copper and zinc distribution within the investigated organs can be attributed to some recently recognized blood cells in the oyster which are rich in zinc and copper. The tissue copper and zinc distribution in this animal depends on where these cells are at the time of sampling. The mussel contains no such cells. 53 references, 7 figures, 1 table.

  7. Assessment of Heavy Metals in Bivalves Molluscs of Apulian Region: a 3-years control activity of a EU Laboratory

    Directory of Open Access Journals (Sweden)

    Miedico O.

    2013-04-01

    Full Text Available The bivalve molluscs represent an important matrix to be studied for several reasons. Their nutritional properties make them valuable to the consumers, so that their consumption and commercial value has risen worldwide. Simultaneously, their significant water-filtering capability and their persistence in the same place make them good bio-indicators of marine ecosystems. The presence of the heavy metal contaminants, as Cd, Pb and Hg, was investigated in bivalve molluscs such as mussels (Mytilus galloprovincialis, clams (Venus gallina and oysters (Ostrea edulis. In the present study, a survey was carried out on 334 samples addressed to the Istituto Zooprofilattico Sperimentale – Puglia e Basilicata, Foggia (ITALY between 2009-2011, and collected by official authorities along the coasts of Apulia Region. The conformity of heavy metal content in bivalve molluscs was verified, in according to EC Reg. 1881/2006. The compliance was found for the total amount of samples. The obtained data on heavy metals concentration in bivalve molluscs were compared with data found in monitoring studies on the incidence of heavy metals in 1981 in North-Western Mediterranean Sea, in 2003 in Tyrrhenian Sea and in 2010 in Pacific Ocean (Chile, reported in literature. The information obtained from this work offer an essential database, not only for the authorities involved in food control, but also for the official institutions responsible of a constant control of the marine ecosystem pollution.

  8. Mixed function oxygenases and xenobiotic detoxication/toxication systems in bivalve molluscs

    Science.gov (United States)

    Moore, M. N.; Livingstone, D. R.; Donkin, P.; Bayne, B. L.; Widdows, J.; Lowe, D. M.

    1980-03-01

    Components of a xenobiotic detoxication/toxication system involving mixed function oxygenases are present in Mytilus edulis. Our paper critically reviews the recent literature on this topic which reported the apparent absence of such a system in bivalve molluscs and attempts to reconcile this viewpoint with our own findings on NADPH neotetrazolium reductase, glucose-6-phosphate dehydrogenase, aldrin epoxidation and other reports of the presence of mixed function oxygenases. New experimental data are presented which indicate that some elements of the detoxication/toxication system in M. edulis can be induced by aromatic hydrocarbons derived from crude oil. This includes a brief review of the results of long-term experiments in which mussels were exposed to low concentrations of the water accommodated fraction of North Sea crude oil (7.7-68 µg 1-1) in which general stress responses such as reduced physiological scope for growth, cytotoxic damage to lysosomal integrity and cellular damage are considered as characteristics of the general stress syndrome induced by the toxic action of the xenobiotics. In addition, induction in the blood cells of microsomal NADPH neotetrazolium reductase (associated with mixed function oxygenases) and the NADPH generating enzyme glucose-6-phosphate dehydrogenase are considered to be specific biological responses to the presence of aromatic hydrocarbons. The consequences of this detoxication/toxication system for Mytilus edulis are discussed in terms of the formation of toxic electrophilic intermediate metabolites which are highly reactive and can combine with DNA, RNA and proteins with subsequent damage to these cellular constituents. Implications for neoplasms associated with the blood cells are also discussed. Finally, in view of the increased use of mussel species in pollutant monitoring programmes, the induction phenomenon which is associated with microsomal enzymes in the blood cells is considered as a possible tool for the

  9. The catch state of mollusc catch muscle is established during activation: experiments on skinned fibre preparations of the anterior byssus retractor muscle of Mytilus edulis L. using the myosin inhibitors orthovanadate and blebbistatin.

    Science.gov (United States)

    Andruchov, Oleg; Andruchova, Olena; Galler, Stefan

    2006-11-01

    Catch is a holding state of muscle where tension is maintained passively for long time periods in the absence of stimulation. The catch state becomes obvious after termination of activation; however, it is possible that catch linkages are already established during activation. To investigate this, skinned fibre bundles of the anterior byssus retractor muscle of Mytilus edulis were maximally activated with Ca(2+) and subsequently exposed to 10 mmol l(-1) orthovanadate (V(i)) or 5 mumol l(-1) blebbistatin to inhibit the force-generating myosin head cross-bridges. Repetitive stretches of about 0.1% fibre bundle length were applied to measure stiffness. Inhibitor application depressed force substantially but never resulted in a full relaxation. The remaining force was further decreased by moderate alkalization (change of pH from 6.7 to 7.4) or by cAMP. Furthermore, the stiffness/force ratio was higher during exposure to V(i) or blebbistatin than during partial Ca(2+) activation producing the same submaximal force. The increased stiffness/force ratio was abolished by moderate alkalization or cAMP. Finally, the stretch-induced delayed force increase (stretch activation) disappeared, and the force recovery following a quick release of the fibre length, was substantially reduced when the force was depressed by V(i) or blebbistatin. All these findings suggest that catch linkages are already established during maximal Ca(2+) activation. They seem to exhibit ratchet properties because they allow shortening and resist stretches. In isometric experiments a force decrease is needed to stress the catch linkages in the high resistance direction so that they contribute to force.

  10. Effects of 5-hydroxytryptamine (serotonin) and forskolin on intracellular free calcium in isolated and fura-2 loaded smooth-muscle cells from the anterior byssus retractor (catch) muscle of Mytilus edulis.

    Science.gov (United States)

    Ishii, N; Simpson, A W; Ashley, C C

    1989-06-01

    Effects of 5-hydroxytryptamine (5-HT) and forskolin on intracellular free calcium concentration [( Ca2+]i) were studied in suspensions of fura-2 loaded smooth-muscle cells from the anterior byssus retractor 'catch' muscle of Mytilus edulis. The successive addition of 5 mM carbachol (CCh) and 100 mM KCl to the suspension evoked a transient elevation of [Ca2+]i from the resting value of 124 +/- 2.7 nM (mean +/- SE, n = 18) to 300-400 nM, which was associated with contraction. The change in [Ca2+]i induced CCh was concentration-dependent with the EC50 of 10(-5) M. The resting [Ca2+]i was unaffected by 10 microM 5-HT. The change in [Ca2+]i induced by 5 mM CCh was suppressed by 5-HT from 167 +/- 14.0 (n = 11) to 124 +/- 14.9 (n = 8) nM whereas that induced by 100 mM KCl was enhanced from 321 +/- 31.9 to 405 +/- 17.6 nM (n = 8). 5-HT applied during the decaying phase of the CCh response caused a rapid decline in [Ca2+]i. In both the responses to CCh and KCl, the falling phase was accelerated by 5-HT. 10 microM forskolin, a potent activator of adenylate cyclase, mimicked the effects of 5-HT as did a membrane-permeant cyclic AMP analogue, 8-parachlorophenylthio cyclic AMP (cpt-cAMP). Application of 100 microM cpt-cAMP partially suppressed the Ca2+i response to CCh and enhanced that to KCl. D-Tubocurarine (500 microM) added during the decaying phase of the response induced by 100 microM CCh, caused a rapid decline in [Ca2+]i similar to that caused by both 5-HT and forskolin.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Predicting growth and mortality of bivalve larvae using gene expression and supervised machine learning.

    Science.gov (United States)

    Bassim, Sleiman; Chapman, Robert W; Tanguy, Arnaud; Moraga, Dario; Tremblay, Rejean

    2015-12-01

    It is commonly known that the nature of the diet has diverse consequences on larval performance and longevity, however it is still unclear which genes have critical impacts on bivalve development and which pathways are of particular importance in their vulnerability or resistance. First we show that a diet deficient in essential fatty acid (EFA) produces higher larval mortality rates, a reduced shell growth, and lower postlarval performance, all of which are positively correlated with a decline in arachidonic and eicosapentaenoic acids levels, two EFAs known as eicosanoid precursors. Eicosanoids affect the cell inflammatory reactions and are synthesized from long-chain EFAs. Second, we show for the first time that a deficiency in eicosanoid precursors is associated with a network of 29 genes. Their differential regulation can lead to slower growth and higher mortality of Mytilus edulis larvae. Some of these genes are specific to bivalves and others are implicated at the same time in lipid metabolism and defense. Several genes are expressed only during pre-metamorphosis where they are essential for muscle or neurone development and biomineralization, but only in stress-induced larvae. Finally, we discuss how our networks of differentially expressed genes might dynamically alter the development of marine bivalves, especially under dietary influence.

  12. Detoxication of metals by marine bivalves: an ultrastructural study of the compartmentation of copper and zinc in the oyster ostrea edulis

    Energy Technology Data Exchange (ETDEWEB)

    George, S.G.; Pirie, B.J.S.; Cheyne, A.R.; Coombs, T.L.; Grant, P.T.

    1978-01-01

    An investigation of the mechanisms of detoxication of copper and zinc by the oyster Ostrea edulis (L) has been carried out using naturally occurring ''green-sick'' (contamination by copper) and unpolluted oysters. Electron microprobe X-ray analysis of tissues in the electron microscope gives direct evidence for the structural compartmentation of copper and zinc in separate, specific, granular amoebocytes. The metals are immobilized in membrane-limited vesicles as different chemical compounds, copper being associated with sulphur and zinc with phosphorus. Chemical analyses of serum and tissues of normal and ''green-sick'' oysters indicate that (a) Cu and Zn are accumulated independently, (b) the Cu and Zn in the serum, while higher than in the surrounding sea water, are maintained at a 10-fold smaller level than the tissues, (c) toxicity is reduced by active uptake from the serum into granular amoebocytes, where it is further reduced by compartmentation in membrane-limited vesicles. It is calculated that the individual cell types may contain as much as 13,000 ppm Cu and 25,000 ppm Zn.

  13. Effects of 5-hydroxytryptamine, dopamine, and acetylcholine on accumulation of cyclic AMP and cyclic GMP in the anterior byssus retractor muscle of Mytilus edulis L. (Mollusca).

    Science.gov (United States)

    Köhler, G; Lindl, T

    1980-02-01

    We investigated in vitro accumulation of adenosine 3',5'-monophosphate (induced by 5-hydroxytryptamine and dopamine) and of guanosine 3',5'-monophosphate (induced by acetylcholine) in the anterior byssus retractor muscle of Mytilus. The response to 5-hydroxytryptamine exceeded that induced by equimolar concentrations of dopamine. 1-methyl lysergic acid, a 5-hydroxytryptamine-blocking agent, diminished the 5-hydroxytryptamine-induced increase of cyclic AMP level. This parallels the effect of this amine on the contracted muscle. Acetylcholine, which causes a tonic contraction of the muscle, increased intracellular levels of cyclic GMP in a dose-dependent (max. 45-fold at 10(-4) M ACh) manner. The time course of the rise in cyclic GMP level was rapid and transient (peak concentration of cyclic GMP at 2 min). Mytolon was the most effective of all cholinergic blockers tested. It was concluded that cyclic nucleotides may play a role in the modulatory process of the transmitters. A direct relation to the relaxation-contraction process could not be established.

  14. Variación temporal de la población de la almeja Darina solenoides y del mejillón Mytilus Edulis Platensis, y su relación con la alimentación del ostrero austral

    Directory of Open Access Journals (Sweden)

    Lorenzo Javier Gallardo

    2014-06-01

    Full Text Available Resumen. El presente trabajo de investigación se ha planteado en el marco de una beca para alumnos avanzados de la UNPA, Unidad Académica Río Gallegos. Tiene como objetivo analizar las variaciones temporales de la población del mejillón Mytilus edulis platensis y de la almeja Darina solenoides y se inserta en un Proyecto de Investigación (29A/227 dirigido por Dra. Z. Lizarralde que tiene como objeto estudiar la ecología trófica del Ostrero Austral (Haematopus leucopodus en el estuario del río Gallegos (Santa Cruz. Durante el 2010 se efectuaron muestreos mensuales (abril a diciembre en un banco de mejillones y otro de almejas, con el objeto de analizar la variación temporal de la densidad y biomasa, y la estructura de tallas poblacional. Se analizó la granulometría y porcentaje de materia orgánica de los sedimentos. El sedimento del banco de mejillones se encuentra constituido en su mayoría por la fracción correspondiente a los gránulos; en el banco de almejas por arenas muy finas (43% y finas (39%. En ambos casos la materia orgánica no supera el 3 %. La densidad de mejillones alcanzó un valor máximo de 2255 individuos/m2 en abril y un mínimo de 497 en noviembre. La biomasa máxima se encontró en abril (110 g/m 2. La densidad de Darina solenoides alcanzó un valor máximo de 565 en junio y un mínimo de 282 individuos/m2 en el mes de octubre. La biomasa máxima ocurrió en diciembre (132 g/m2. No se detectó el período de reclutamiento de nuevos individuos en los bancos de las especies estudiadas.

  15. Shell fluctuating asymmetry in the sea-dwelling benthic bivalve Mytilus galloprovincialis (Lamarck, 1819) as morphological markers to detect environmental chemical contamination.

    Science.gov (United States)

    Scalici, Massimiliano; Traversetti, Lorenzo; Spani, Federica; Malafoglia, Valentina; Colamartino, Monica; Persichini, Tiziana; Cappello, Simone; Mancini, Giuseppe; Guerriero, Giulia; Colasanti, Marco

    2017-02-10

    Investigations on asymmetries showed that deviations from perfect bilateral symmetry are interpreted as environmental changes inducing developmental instability. Since morphological abnormalities increase with pollution, deformations may be considered indicators of the organism exposition to pollution. Therefore, the onset of asymmetry in otherwise normally symmetrical traits has been used as a measure of some stresses as well. In this context, we studied how marine pollution affects the valve morphological alterations in the mussel Mytilus galloprovincialis. We used 180 specimens (30 per site) from the aquaculture area of Goro (River Po delta, northern Adriatic Sea), translocated, and released within 50 × 50 × 50 cm cages in five sites: two disturbed and one undisturbed near Naples (eastern Tyrrhenian Sea), and one disturbed and one undisturbed near Siracusa (western Ionian Sea). Disturbed sites were stressed by heavy industrialization and heavy tankers traffic of crude and refined oil, and were defined basing on sediment contamination. In particular, by the cone-beam computed tomography we obtained 3D virtual valve surfaces to be analyzed by the geometric morphometric techniques. Specifically, we focused the levels of the shell shape fluctuating asymmetry in relation to the degrees of marine pollution in different sites of the Tyrrhenian Sea. The Mahalanobis distances (interpreted as proxy of the individual shape asymmetry deviation from the mean asymmetry) significantly regressed with the sediment contamination gradient. Indeed, although the left-right differences were normally distributed in each studied site, the individual asymmetry scores (IAS) significantly varied amongst the investigated sites. IAS showed higher values in disturbed areas than those of undisturbed ones in both Tyrrhenian and Ionian Sea. Our results are consistent with past studies on molluscans and other taxa, demonstrating some detrimental effects of chemicals on organisms

  16. Marine bivalve geochemistry and shell ultrastructure from modern low pH environments

    Directory of Open Access Journals (Sweden)

    S. Hahn

    2011-10-01

    Full Text Available Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis (from the Mediterranean and M. edulis (from the Wadden Sea combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island of Ischia. The shells of transplanted mussels were compared with M. edulis collected at pH ~8.2 from Sylt (German Wadden Sea. Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

  17. Marine bivalve geochemistry and shell ultrastructure from modern low pH environments

    Science.gov (United States)

    Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

    2011-10-01

    Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis (from the Mediterranean) and M. edulis (from the Wadden Sea) combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island of Ischia. The shells of transplanted mussels were compared with M. edulis collected at pH ~8.2 from Sylt (German Wadden Sea). Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

  18. Lead and other heavy metals (cadmium and mercury accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas sampled in Sardinia in 2008-2012

    Directory of Open Access Journals (Sweden)

    Pierluigi Piras

    2013-12-01

    Full Text Available The Sardinian shellfish farming, like the national, is mainly focused on mussels and carpet-shell clams, still less on cupped oyster farming. After Olbia’s Gulf, various lagoon areas along the coastal perimeter have been interested to shellfish farming. They are transitional waters, whose state of pollution must be evaluated both as ecosystem’s health and as directly/indirectly human risk. This also applies to heavy metals such as lead, cadmium and mercury, arising both from anthropogenic that geological-natural activity. The aim of the present study is to investigate the variability of the concentrations of these metals in different mollusks to make a comparative assessment, detect trends (over the five-years or cyclicrecurring and identify hot spots. In 2008- 2012, 984 samples have been analysed by inductively coupled plasma mass spectrometry technique. Of them, 599 in pre-marketing (for classification of production areas or their monitoring and the remaining during marketing. The difference between the average levels of the three metals in the different mollusks species was statistically significant, with Pb>Cd>Hg, and there was evidence of a gradual downward trend, albeit moderate, in the contamination levels, with a significant seasonality in concentrations levels, of lead in particular. Also comparisons between the bio-monitored coastal areas were statistically different. Since the samples were representative of the entire production of bivalve mollusks in Sardinia and the contamination allowable limits have never been exceeded in the products marketed, it can be concluded that these products are safe, pointing out that maintenance of monitoring/surveillance plans provides useful information species-dependent, site-specific and temporal trends.

  19. p53 Superfamily proteins in marine bivalve cancer and stress biology.

    Science.gov (United States)

    Walker, Charles W; Van Beneden, Rebecca J; Muttray, Annette F; Böttger, S Anne; Kelley, Melissa L; Tucker, Abraham E; Thomas, W Kelley

    2011-01-01

    The human p53 tumour suppressor protein is inactivated in many cancers and is also a major player in apoptotic responses to cellular stress. The p53 protein and the two other members of this protein family (p63, p73) are encoded by distinct genes and their functions have been extensively documented for humans and some other vertebrates. The structure and relative expression levels for members of the p53 superfamily have also been reported for most major invertebrate taxa. The functions of homologous proteins have been investigated for only a few invertebrates (specifically, p53 in flies, nematodes and recently a sea anemone). These studies of classical model organisms all suggest that the gene family originally evolved to mediate apoptosis of damaged germ cells or to protect germ cells from genotoxic stress. Here, we have correlated data from a number of molluscan and other invertebrate sequencing projects to provide a framework for understanding p53 signalling pathways in marine bivalve cancer and stress biology. These data suggest that (a) the two identified p53 and p63/73-like proteins in soft shell clam (Mya arenaria), blue mussel (Mytilus edulis) and Northern European squid (Loligo forbesi) have identical core sequences and may be splice variants of a single gene, while some molluscs and most other invertebrates have two or more distinct genes expressing different p53 family members; (b) transcriptional activation domains (TADs) in bivalve p53 and p63/73-like protein sequences are 67-69% conserved with human p53, while those in ecdysozoan, cnidarian, placozoan and choanozoan eukaryotes are ≤33% conserved; (c) the Mdm2 binding site in the transcriptional activation domain is 100% conserved in all sequenced bivalve p53 proteins (e.g. Mya, Mytilus, Crassostrea and Spisula) but is not present in other non-deuterostome invertebrates; (d) an Mdm2 homologue has been cloned for Mytilus trossulus; (e) homologues for both human p53 upstream regulatory and

  20. Histological responses of marine mussel Mytilus edulis to long-term exposure to sublethal-level of lindane and atrazine%紫贻贝长期暴露于亚致死剂量的林丹和阿特拉津下的组织学反应

    Institute of Scientific and Technical Information of China (English)

    Nahla S. EI-SHENAWY; Richard GREENWOOD; Ismail M. ABDEL-NABI

    2007-01-01

    Histological changes in tissues of the sentinel bivalve species Mytilus edulis were examined following a long-term exposure to sub-lethal levels of gamma-hexachlorocyclohexane(γ-HCH) and 2-chloro-4-ethylamino-6-isopropylamino-s-triazine(atrazine) to investigate the potential of such changes as fast and sensitive biomarkers of exposure to pesticides. M.edulis readily bioaccumulates environmental pesticides, and in this project the relationship between accumulation of selected pesticides and histopathological effects was studied. Mussels and water samples were analysed for γ-HCH and atrazine by GC/MSD. The mussels were taken to the laboratory and kept for a 21 day period in order to let their metabolism adjust to a continuous closed flow system with quality water control. After that period, 30 organisms were exposed either to sublethal concentrations of γ-HCH(0.9 mg/L) or atrazine(3.583 mg/L) for 56 days. During the experiment, important parameters such as temperature(18℃) and salinity(34‰) were controlled. Mussels were sampled to determine histological damage, and the concentration of pesticide levels at 28 and 56 days. Exposed organisms accumulated around 304.8-372.0 and 83.3-137.4 μg/g dry weight of γ-HCH and atrazine, respectively. Most histological alterations were highly localized in the epithelium of the gills and mantle tissues; epithelia were found to be detached from the remaining tissue parts. Histopathological results showed the activation of resistance mechanisms that allow mussels to survive under sublethal stresses. The histopathological effects ranged from infiltration responses up to mediated cellular responses, characterized by the presence of hemolymph cells. Histological and ultrastructural changes in various tissues were positively correlated with the bioaccumulation of the pesticides, suggesting that they may serve as biomarkers for pesticide exposure.%为开发快速、敏感的生物标记物以监测海洋贝类生物中是否存在

  1. Complete amino acid sequence of Mytilus anterior byssus retractor paramyosin and its putative phosphorylation site.

    Science.gov (United States)

    Watabe, S; Iwasaki, K; Funabara, D; Hirayama, Y; Nakaya, M; Kikuchi, K

    2000-01-01

    A cDNA encoding the full-length paramyosin molecule was cloned from the mussel Mytilus galloprovincialis, a species closely related to Mytilus edulis. It contained 3,497 nucleotides (nt), with 79 and 826 nt for the 5' and 3' non-coding regions, respectively. The coding region was composed of 2,592 nt for 864 amino acid residues, a size typical of paramyosin. While genomic DNA digests with either HindIII or PstI exhibited a single band when hybridized with a SacI fragment of paramyosin cDNA, the digests with either EcoRV or EcoRI showed two bands, suggesting that the mussel has at least two genes encoding paramyosin. The mRNAs encoding paramyosin were most abundant in muscle tissues from byssus retractor and adductor muscles. Only traces of paramyosin transcripts were found in the tissue of foot, gill, inner mantle, and outer mantle. The same phosphorylatable peptide previously reported for paramyosin from the bivalve Mercenaria mercenaria, Ser-Arg-Ser-Met-Ser(P)-Val-Ser-Arg (Watabe et al. 1989. Comp Biochem Physiol 94B:813-821) was found in the C-terminal non-helical part of this Mytilus paramyosin. We predict that this particular paramyosin has a coiled-coil structure composed of two alpha-helices that show the heptad repeats (a-b-c-d-e-f-g) with further 28-amino acid repeat zones, where a and d tend to be occupied by nonpolar residues.

  2. Further identification of bioactive peptides in the anterior byssus retractor muscle of Mytilus: two contractile and three inhibitory peptides.

    Science.gov (United States)

    Fujisawa, Y; Takahashi, T; Ikeda, T; Muneoka, Y; Kubota, I; Minakata, H; Nomoto, K; Nose, T; Miki, W

    1993-09-01

    1. Two contractile and three inhibitory peptides were newly isolated from the anterior byssus retractor muscles (ABRMs) of the bivalve mollusc Mytilus edulis by using the muscle as the bioassay system. 2. The structures of the two contractile peptides were GPFGTHIKamide (GPFG-8) and GPFGLNKHGamide (GPFG-9). The contractile response of the ABRM to the first-time application of GPFG-8 or GPFG-9 was of considerable size. The threshold concentrations of the peptides were around 10(-9) M. However, the contractile response to the second-time application was far smaller than that to the first-time application in both cases. Namely, the muscle showed tachyphylaxis to the peptides. 3. Two of the three inhibitory peptides were members of the Mytilus-inhibitory-peptide (MIP) family. Their structures were RAPLFIamide (MIP6) and RSPMFVamide (MIP7). The peptides, as well as the other MIPs previously identified, showed a potent inhibitory effect on phasic contraction of the ABRM in response to repetitive electrical stimulation. The remaining one was an MIP-related peptide (MIP-RP) having the sequence of MRYFVamide. The MIP-RP was less potent than the two MIPs in inhibiting the contraction of the ABRM.

  3. Genetic diversity and connectivity within Mytilus spp. in the subarctic and Arctic

    DEFF Research Database (Denmark)

    Mathiesen, Sofie Smedegaard; Thyrring, Jakob; Hansen, Jakob Hemmer;

    2016-01-01

    in the European Arctic. Mytilus edulis was the most abundant species found with a clear genetic split between populations in Greenland and the Eastern Atlantic. Surprisingly, analyses revealed the presence of M. trossulus in high Arctic NW Greenland (77°N) and M. galloprovincialis or their hybrids in SW Greenland......Climate changes in the Arctic are predicted to alter distributions of marine species. However, such changes are difficult to quantify because information on present species distribution and the genetic variation within species is lacking or poorly examined. Blue mussels, Mytilus spp. are ecosystem...... engineers in the coastal zone globally. In order to improve knowledge of distribution and genetic structure of the Mytilus edulis complex in the Arctic, we analyzed 81 SNPs in 534 Mytilus spp. individuals sampled at 13 sites to provide baseline data for distribution and genetic variation of Mytilus mussels...

  4. Biosorption of thorium on the external shell surface of bivalve mollusks: the role of shell surface microtopography.

    Science.gov (United States)

    Zuykov, Michael; Pelletier, Emilien; Saint-Louis, Richard; Checa, Antonio; Demers, Serge

    2012-02-01

    External shell surface (ESS) of bivalve mollusks is known to adsorb various metals dissolved in ambient water in high concentration. It is hypothesized here that the surface microtopography of the thin organic coating layer, periostracum, or calcareous shell (if periostracum was destroyed) plays a major role in the adsorption of actinides on ESS. Thorium (natural alpha-emitter) was used in short-term biosorption experiment with shell fragments of five bivalve mollusks. After a 72 h exposure to Th (~6 kBq L(-1)), thorium concentration was measured on ESS using laser ablation inductively coupled plasma mass spectrometry; the distribution and density of alpha tracks were subsequently visualized by α-track autoradiography. A trend in reduced Th concentrations on the ESS was observed depending upon the species tested: (group 1 ~4000 μg g(-1)) Chlamys islandica (M.), Mercenaria mercenaria (L.), Dreissena polymorpha (P.)>(group 2 ~1200 μg g(-1)) Crassostrea virginica (G.)≫(group 3 ~150 μg g(-1)) Mytilus edulis L. The microtopography of ESS was characterized by scanning electron microscopy revealing the high porosity of the calcareous surface of C. islandica and M. mercenaria, lamellate surface of periostracum in D. polymorpha, uneven but a weakly porous surface of periostracum of C. virginica, and a nearly smooth surface of the periostracum of M. edulis. This work has demonstrated, for the first time, the presence of a strong correlation between concentration of adsorbed Th and ESS microtopography, and the role of the periostracum in this process is discussed.

  5. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  6. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Science.gov (United States)

    Alberti, Angelo; Chiaravalle, Eugenio; Fuochi, Piergiorgio; Macciantelli, Dante; Mangiacotti, Michele; Marchesani, Giuliana; Plescia, Elena

    2011-12-01

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy.We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with 60Co γ-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO2-, CO33-, SO2- and SO3- radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters.

  7. Occurrence of pharmaceuticals and endocrine disrupting compounds in macroalgaes, bivalves, and fish from coastal areas in Europe

    NARCIS (Netherlands)

    Álvarez-Muñoz, D.; Rodríguez-Mozaz, S.; Maulvault, A.L.; Tediosi, A.; Fernández-Tejedor, M.; Heuvel, Van den F.; Kotterman, M.; Marques, A.; Barceló, D.

    2015-01-01

    The ocurrence and levels of PhACs, Endocrine Disrupting and related Compounds (EDCs) in seafood from potential contaminated areas in Europe has been studied. Macroalgae (S. accharina latissima and Laminaria digitata), bivalves (Mytilus galloprovincialis, Mytilus spp., Chamalea gallina and Crassos

  8. Layer-by-Layer Proteomic Analysis of Mytilus galloprovincialis Shell.

    Directory of Open Access Journals (Sweden)

    Peng Gao

    Full Text Available Bivalve shell is a biomineralized tissue with various layers/microstructures and excellent mechanical properties. Shell matrix proteins (SMPs pervade and envelop the mineral crystals and play essential roles in biomineralization. Despite that Mytilus is an economically important bivalve, only few proteomic studies have been performed for the shell, and current knowledge of the SMP set responsible for different shell layers of Mytilus remains largely patchy. In this study, we observed that Mytilus galloprovincialis shell contained three layers, including nacre, fibrous prism, and myostracum that is involved in shell-muscle attachment. A parallel proteomic analysis was performed for these three layers. By combining LC-MS/MS analysis with Mytilus EST database interrogations, a whole set of 113 proteins was identified, and the distribution of these proteins in different shell layers followed a mosaic pattern. For each layer, about a half of identified proteins are unique and the others are shared by two or all of three layers. This is the first description of the protein set exclusive to nacre, myostracum, and fibrous prism in Mytilus shell. Moreover, most of identified proteins in the present study are novel SMPs, which greatly extended biomineralization-related protein data of Mytilus. These results are useful, on one hand, for understanding the roles of SMPs in the deposition of different shell layers. On the other hand, the identified protein set of myostracum provides candidates for further exploring the mechanism of adductor muscle-shell attachment.

  9. Layer-by-Layer Proteomic Analysis of Mytilus galloprovincialis Shell.

    Science.gov (United States)

    Gao, Peng; Liao, Zhi; Wang, Xin-Xing; Bao, Lin-Fei; Fan, Mei-Hua; Li, Xiao-Min; Wu, Chang-Wen; Xia, Shu-Wei

    2015-01-01

    Bivalve shell is a biomineralized tissue with various layers/microstructures and excellent mechanical properties. Shell matrix proteins (SMPs) pervade and envelop the mineral crystals and play essential roles in biomineralization. Despite that Mytilus is an economically important bivalve, only few proteomic studies have been performed for the shell, and current knowledge of the SMP set responsible for different shell layers of Mytilus remains largely patchy. In this study, we observed that Mytilus galloprovincialis shell contained three layers, including nacre, fibrous prism, and myostracum that is involved in shell-muscle attachment. A parallel proteomic analysis was performed for these three layers. By combining LC-MS/MS analysis with Mytilus EST database interrogations, a whole set of 113 proteins was identified, and the distribution of these proteins in different shell layers followed a mosaic pattern. For each layer, about a half of identified proteins are unique and the others are shared by two or all of three layers. This is the first description of the protein set exclusive to nacre, myostracum, and fibrous prism in Mytilus shell. Moreover, most of identified proteins in the present study are novel SMPs, which greatly extended biomineralization-related protein data of Mytilus. These results are useful, on one hand, for understanding the roles of SMPs in the deposition of different shell layers. On the other hand, the identified protein set of myostracum provides candidates for further exploring the mechanism of adductor muscle-shell attachment.

  10. Layer-by-Layer Proteomic Analysis of Mytilus galloprovincialis Shell

    Science.gov (United States)

    Wang, Xin-xing; Bao, Lin-fei; Fan, Mei-hua; Li, Xiao-min; Wu, Chang-wen; Xia, Shu-wei

    2015-01-01

    Bivalve shell is a biomineralized tissue with various layers/microstructures and excellent mechanical properties. Shell matrix proteins (SMPs) pervade and envelop the mineral crystals and play essential roles in biomineralization. Despite that Mytilus is an economically important bivalve, only few proteomic studies have been performed for the shell, and current knowledge of the SMP set responsible for different shell layers of Mytilus remains largely patchy. In this study, we observed that Mytilus galloprovincialis shell contained three layers, including nacre, fibrous prism, and myostracum that is involved in shell-muscle attachment. A parallel proteomic analysis was performed for these three layers. By combining LC-MS/MS analysis with Mytilus EST database interrogations, a whole set of 113 proteins was identified, and the distribution of these proteins in different shell layers followed a mosaic pattern. For each layer, about a half of identified proteins are unique and the others are shared by two or all of three layers. This is the first description of the protein set exclusive to nacre, myostracum, and fibrous prism in Mytilus shell. Moreover, most of identified proteins in the present study are novel SMPs, which greatly extended biomineralization-related protein data of Mytilus. These results are useful, on one hand, for understanding the roles of SMPs in the deposition of different shell layers. On the other hand, the identified protein set of myostracum provides candidates for further exploring the mechanism of adductor muscle-shell attachment. PMID:26218932

  11. Genetic composition of Mytilus species in mussel populations from southern Chile Composición genética de especies de Mytilus en poblaciones de mejillón del sur de Chile

    Directory of Open Access Journals (Sweden)

    María Angélica Larraín

    2012-11-01

    Full Text Available Mussels are one of the most cultivated and commercialized bivalves worldwide and in southern Chile its culture represent an important economic activity. The species identification within the Mytilus genera, by morphological features, is unreliable, so we used a polymorphism RFLP in the gene encoding the polyphenolic adhesive protein as a species-specific genetic marker to describe Mytilus species diversity in southern Chile, and evaluate possible applications in traceability, food quality and safety. Using Me 15-16 marker most mussels were M. chilensis, finding no other pure individuals; however, putative hybrids of M. chilensis x M. trossulus and M. chilensis x M. galloprovincialis were detected. There was no evidence of M. edulis. The presence of the M. trossulus allele, faraway from its distribution area, demands further analysis with different genetic markers to allow a better understanding of its origin. In addition, the correspondence between markers that distinguishes northern from southern hemisphere M. galloprovincialis, with those who discriminates between M. chilensis and M. galloprovincialis would contribute to the taxonomic status of Chilean blue mussels. In Chile, the genetic composition of Mytilus indicates that geographical origin of mussels and its traceability cannot be established merely from the identification of the species. The use of other markers would be required.Los mejillones son una de las especies de bivalvos más cultivadas y comercializadas, en el sur de Chile donde su cultivo representa una actividad económica importante. La identificación de la especie dentro del género Mytilus, basada en las características morfológicas no es confiable por lo que se utilizó un polimorfismo RFLP en el gen que codifica la proteína adhesiva polifenólica como marcador genético específico de la especie para describir la diversidad de especies Mytilus en el sur de Chile, y evaluar posibles aplicaciones en trazabilidad

  12. Cross-habitat interactions among bivalve species control community structure on intertidal flats

    NARCIS (Netherlands)

    Donadi, Serena; van der Heide, Tjisse; van der Zee, Els M.; Eklöf, Johan S.; van de Koppel, Johan; Weerman, Ellen J.; Piersma, Theunis; Olff, Han; Eriksson, Britas Klemens

    2013-01-01

    Increasing evidence shows that spatial interactions between sedentary organisms can structure communities and promote landscape complexity in many ecosystems. Here we tested the hypothesis that reef-forming mussels (Mytilus edulis L.), a dominant intertidal ecosystem engineer in the Wadden Sea, prom

  13. Polychlorinated biphenyls, organochlorine pesticides and trace metals in cultured and harvested bivalves from the eastern Adriatic coast (Croatia).

    Science.gov (United States)

    Milun, Vesna; Lušić, Jelena; Despalatović, Marija

    2016-06-01

    Polychlorinated biphenyls, organochlorine pesticides and trace metals were determined in tissues of bivalve molluscs (Mytilus galloprovincialis, Ostrea edulis, Venus verrucosa, Arca noae and Callista chione), collected from 11 harvesting and 2 cultured locations along the eastern Adriatic coast, in May and November 2012. Concentrations (ng g(-1) dry weight) of organochlorines ranged from 1.53 to 21.1 for PCBs and 0.68 to 5.21 for p,p'-DDTs. HCB, lindane, heptachlor and aldrin-like compounds were found in lower levels or were not detected. Metal concentrations (mg kg(-1) dry weight) ranged from 0.23 to 4.03 for Cd, 0.87-3.43 for Cr, 3.69-202.3 for Cu, 0.06-0.26 for HgT, 0.62-9.42 for Ni, 0.95-4.64 for Pb, and 55.76-4010.3 for Zn. Established organochlorine and trace metal levels were lower than the maximum allowable levels in seafood set by the European Commission.

  14. On the identity of broad-shelled mussels (Mollusca, Bivalvia, Mytilus) from the Dutch delta region

    NARCIS (Netherlands)

    Groenenberg, D.S.J.; Wesselingh, F.P.; Rajagopal, S.; Jansen, J.M.; Bos, M.M.; Velde, van der G.; Gittenberger, E.; Hoeksema, B.W.; Raad, H.; Hummel, H.

    2011-01-01

    Late Quaternary (Eemian) deposits of the Netherlands contain shells that resemble those of living Mytilus galloprovincialis. Similar broad-shelled mytilids also occur in estuaries of the southwestern Netherlands together with slender individuals typical of M. edulis. We sampled living mussels along

  15. Validation of the flow-through chamber (FTC and steady-state (SS methods for clearance rate measurements in bivalves

    Directory of Open Access Journals (Sweden)

    Poul S. Larsen

    2011-09-01

    To obtain precise and reliable laboratory clearance rate (filtration rate measurements with the ‘flow-through chamber method’ (FTC the design must ensure that only inflow water reaches the bivalve's inhalant aperture and that exit flow is fully mixed. As earlier recommended these prerequisites can be checked by a plot of clearance rate (CR versus increasing through-flow (Fl to reach a plateau, which is the true CR, but we also recommend to plot percent particles cleared versus reciprocal through-flow where the plateau becomes the straight line CR/Fl, and we emphasize that the percent of particles cleared is in itself neither a criterion for valid CR measurement, nor an indicator of appropriate ‘chamber geometry’ as hitherto adapted in many studies. For the ‘steady-state method’ (SS, the design must ensure that inflow water becomes fully mixed with the bivalve's excurrent flow to establish a uniform chamber concentration prevailing at its incurrent flow and at the chamber outlet. These prerequisites can be checked by a plot of CR versus increasing Fl, which should give the true CR at all through-flows. Theoretically, the experimental uncertainty of CR for a given accuracy of concentration measurements depends on the percent reduction in particle concentration (100×P from inlet to outlet of the ideal ‘chamber geomety’. For FTC, it decreases with increasing values of P while for SS it first decreases but then increases again, suggesting the use of an intermediate value of P. In practice, the optimal value of P may depend on the given ‘chamber geometry’. The fundamental differences between the FTC and the SS methods and practical guidelines for their use are pointed out, and new data on CR for the blue mussel, Mytilus edulis, illustrate a design and use of the SS method which may be employed in e.g. long-term growth experiments at constant algal concentrations.

  16. Lower Jurassic beds with bivalves in south Slovenia

    Directory of Open Access Journals (Sweden)

    Irena Debeljak

    1995-12-01

    Full Text Available The Lower Jurassic beds of south Slovenia outcrop on a surface of several hundred km^ with their thickness in places exceeding 300 meters. They were deposited on the Dinaric Carbonate Platform. In them rich accumulations of characteristic bivalves occur that in Pliensbachian and Toarcian inhabited the wide interconnected shallow water regions of the western and southern margins of Tethysand the eastern Pacific. The most interesting are three large bivalve species:Lithiotis problematica, Cochlearites loppianus and Lithiopedalion scutatus.In addition, numerous other genera can be found: Gervilleiopema, Mytilus, Opisoma and Pachyrisma (with subgenera Pachymegalodon and Durga.The bivalves formed in the region of south Slovenia, in the prevailingly quiet environment of the restricted shelf, sea-bottom mats or biostromes. Their shells can be only rarely found in their growth position. The horizon with bivalves ("lithiotid horizon" in south Slovenia is attributed to Pliensbachian (Domerian. It isup to 75 metres thick and it almost does not pinch out. Within it individual lumachelles of bivalves occur which are from several centimetres to ten metres thick.They are almost exclusively associated with dark, micritic, in places marly limestone and bituminous dolomite. The biodiversity in lumachelles is very low. The intermediate beds that do not contain bivalves mostly consist of oolitic and biospariticlimestone. In this article some localities from various areas of the carbonate platform are described. Considered are paleogeographical and paleoecological conditions that permitted the existence of this typical bivalve fauna.

  17. Growth potential of blue mussels (M. edulis) exposed to different salinities evaluated by a Dynamic Energy Budget model

    DEFF Research Database (Denmark)

    Maar, Marie; Saurel, Camille; Landes, Anja;

    2015-01-01

    For bluemussels,Mytilus edulis, onemajor constrain in the Baltic Sea is the low salinities that reduce the efficiency of mussel production. However, the effects of living in low and variable salinity regimes are rarely considered in models describing mussel growth. The aim of the present study wa...

  18. Cruzamientos interpoblacionales en Mytilus chilensis, un bivalvo de importancia comercial y sus efectos sobre el crecimiento en longitud de la valva durante la etapa larval Inter-population breeding in Mytilus chilensis, an economically important bivalve, and its effects on the shell length during the larval stage

    Directory of Open Access Journals (Sweden)

    JE Toro

    2008-01-01

    Full Text Available Dos poblaciones naturales de Mytilus chilensis aisladas geográficamente fueron utilizadas para realizar los cruzamientos experimentales en el presente trabajo. En todos los cruzamientos, utilizando un diseño factorial con réplicas, ocurrió fertilización de las ovas, no detectándose diferencias significativas entre los cruzamientos intra e interpoblacionales en cuanto al porcentaje de ovas que desarrollaron larvas al día 4 (P > 0,05. Sin embargo, el porcentaje de larvas anormales al día 4 fue significativamente mayor en los cruzamientos interpoblacionales (P Two geographically separated natural populations of Mytilus chilensis were utilized to carry out the experimental crosses on the present study. In every crossing, using the factorial design with replication, fertilization of eggs occurred without detection of significant differences among inter and intra-population crosses in relation to percentage of eggs developed into larvae at day 4 (P > 0.05. However, the percentage of abnormal larvae at day 4, was significantly higher among inter-population crosses (P < 0.05. The larvae from each cross were placed into a 200 l fiber-glass tank containing 1 µm filtered and U.V. treated fresh sea water, at a density of 100 larvae per ml. A high cell concentration of the micro algae Isochrysis galbana was used as food. Samples for analyzing larval growth were taken from the larval cultures at 4, 10 and 20 days after fertilization. Larval samples were videotyped from a plankton decantation chamber in an inverted microscope fitted with a Pulnex video camera. Selected images were captured for subsequent processing and measurement of each larva using a Scion Image 3.0b PC Software. Significantly differences (P < 0.05 were found in the size of the larvae among the experimental crosses. The sibs from inter-population crosses showed significantly (P < 0.05 higher sizes than those produced by the intra-population crosses. These higher values in the shell

  19. In-situ bioassays using caged bivalves

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    It is important to make the distinction between chemical measurements to assess bioaccumulation potential versus biological measurements to assess potential bioeffects because bioaccumulation is not a bioeffect. Caging provides a unique opportunity to make synoptic measurements of each and facilitates making these measurements over space and time. Measuring bioaccumulation in resident and transplanted bivalves has probably been the most frequently used form of an in-situ bioassay because bivalves concentrate chemicals in their tissues. They are also easy to collect, cage, and measure. The authors have refined bivalve bioassay methods by minimizing the size range of test animals, making repetitive measurements of the same individuals, and standardizing test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Growth measurements can serve two purposes in this assessment strategy: (1) An integrated biological response endpoint that is easily quantifiable and with significance to the population, and (2) A means of calibrating bioaccumulation by assessing the relative health and physiological state of tissues that have accumulated the chemicals. In general, the authors have found the highest bioconcentration factors associated with the highest growth rates, the highest concentrations ({micro}g/g) of chemicals in juvenile mussels, and the highest chemical content ({micro}g/animal) in adult mussels. Without accounting for possible dilution of chemical concentrations by tissue growth or magnification through degrowth, contaminant concentrations can be misleading. Examples are provided for the Sudbury River in Massachusetts (Elliptio complanata), San Diego Bay (Mytilus galloprovincialis), and the Harbor Island Superfund Site in Puget Sound (Mytilus trossulus).

  20. Changes in distribution patterns of 0-group bivalves in the Wadden Sea: Byssus-drifting releases juveniles from the constraints of hydrography

    Science.gov (United States)

    Armonies, W.

    1996-06-01

    The large-scale (km) distributional patterns of juvenile bivalves are established by larval settlement and subsequently changed due to actively initiated postlarval migrations (byssus-drifting), resuspension during sediment disturbance, and local differences in mortality. Repeated mapping of 0-group bivalve distribution during two summers was combined with simultaneous registrations of the numbers of drifting specimens. Species differed in their susceptibility to passive resuspension and their activity in byssus-drifting, but the two ways of entry into the water column were independent of each other. As a result, the relative magnitude of byssus-drifting and passive resuspension varied with the species. While hydrographical conditions always determined the changes in the distributional patterns of passively eroded species, this was not the case in active migrations of byssus-drifting bivalves. A comparison of the distributional patterns of juveniles over two consecutive years showed similar patterns in the tellinid clam Macoma balthica and the razor clam Ensis americanus. In these two species spatfall mainly occurred around mean low-tide level. Subsequently, juvenile M. balthica rapidly accumulated in the upper intertidal, whereas juvenile E. americanus accumulated subtidally. In mussels Mytilus edulis the distribution of juveniles only changed in a longshore direction, not in the tidal level occupied. The spatial pattern of cockles Cerastoderma edule changed from aggregation of the early spat in the mid and lower intertidal towards a more uniform distribution of recruits over these tidal flats. There were only a few patches of high abundance left at the end of summer. Finally, in juvenile clams Mya arenaria the spatial patterns of both spatfall and redistribution were unpredictable. On a km-scale, abundance of some species correlated with sediment granulometry. Presumably, this does not reflect a causal relationship but is a consequence of the correlation between

  1. Differences in sperm ultrastructure between Mytilus chilensis and Mytilus galloprovincialis (Bivalvia, Mytilidae: could be used as a taxonomic trait?

    Directory of Open Access Journals (Sweden)

    Pablo A Oyarzún

    2014-03-01

    Full Text Available The sperm ultrastructure has been used to solve several systematic and phylogenetic problems in marine invertebrates. The sperm ultrastructure of the Chilean mussel Mytilus chilensis and Mytilus galloprovincialis corresponds to the ect-aquasperm type. Sperm from both taxa measured 55-60 μm between head (acrosome + nucleus, midpiece (only 5 mitochondria and the flagellum which in its end piece has a smaller diameter tail. The differences between both taxa are clearly shown, in the structure of the acrosome and nucleus. Therefore, according to our results and those reported in the literature, we indicate that Chilean native mussel sperm is different from other species of the Mytilus complex (M. trossulus, M. galloprovincialis and M. edulis. These differences in sperm ultrastructure found in M. chilensis, are another trait that can be used to validate the taxonomic status of the species. Differences in sperm morphology are related with reproductive isolation, and probably will be useful to understand future data on speciation. Finally, we discussed the finding that Mytilus galloprovincialis sperm from Chile have an acrosome notoriously smaller than those reported for specimens from Europe and Africa, though they have a great similarity with specimens from Japan, as reported in the literature.

  2. Nursery function of coastal temperate benthic habitats: New insight from the bivalve recruitment perspective

    Science.gov (United States)

    Barbier, Pierrick; Meziane, Tarik; Forêt, Martin; Tremblay, Réjean; Robert, René; Olivier, Frédéric

    2017-03-01

    Marine habitat function has been typically investigated in terms of biogeochemical regulation but rarely in terms of population renewal, which is mainly controlled by recruitment dynamics. The recruitment phase is crucial for organisms with a bentho-pelagic life cycle, such as bivalves, and it regulates the population renewal success. This study provides new insight on the role of temperate benthic habitats on bivalve recruitment, as a function of nursery areas. Six dominant benthic habitats of the Chausey archipelago (Normandy, France) were studied. In each habitat, bivalve recruit assemblages were described at the end of two reproductive seasons. Furthermore, Ostrea edulis juveniles were immerged on each habitat during two months to compare growth performances and feeding status, estimated by fatty acid composition. Recruit assemblages differ from each habitat according to sediment grain-size composition and bathymetrical levels. Subtidal habitats, and especially Crepidula fornicata banks and Glycymeris glycymeris coarse sands, supported the highest species abundance and richness of recruits. All O. edulis juveniles fed on the same trophic resources but digestive glands of juveniles from C. fornicata banks were more concentrated in total fatty acids than those from subtidal G. glycymeris coarse sands and maerl banks. Our results depict the key role of subtidal and structured habitats, composed of ecosystem engineers, in enhancing bivalve recruitment and extending the bivalve population renewal. This study suggests that the crucial role of these habitats as bivalve nurseries must be integrated in management perspectives.

  3. Adaptive morphologies and guild structure in a high-diversity bivalve fauna from an early Campanian rocky shore, Ivö Klack (Sweden)

    DEFF Research Database (Denmark)

    Sørensen, Anne Mehlin; Surlyk, Finn; Jagt, John W. M.

    2012-01-01

    The bivalve fauna from a late early Campanian rocky shore at Ivö Klack (southern Sweden), comprises just over sixty species, a very high diversity in comparison to other Late Cretaceous and modern rocky shore bivalve assemblages. This high diversity is here considered to represent a reliable census...... adjacent environments. It includes some of the most northerly known, very small rudistid bivalves, in addition to the oldest known occurrences of Mytilus and Barbatia in association with rocky shores. Bivalves constituted the most important invertebrate group inhabiting the late early Campanian rocky shore...

  4. Differences in copper bioaccumulation and biological responses in three Mytilus species.

    Science.gov (United States)

    Brooks, Steven J; Farmen, Eivind; Heier, Lene Sørlie; Blanco-Rayón, Esther; Izagirre, Urtzi

    2015-03-01

    Mytilus species are important organisms in marine systems being highly abundant and widely distributed along the coast of Europe and worldwide. They are typically used in biological effects studies and have a suite of biological effects endpoints that are frequently measured and evaluated for stress effects in laboratory experiments and field monitoring programmes. Differences in bioaccumulation and biological responses of the three Mytilus species following exposure to copper (Cu) were investigated. A laboratory controlled exposure study was performed with three genetically confirmed Mytilus species; M. galloprovincialis, M. edulis and M. trossulus. Chemical bioaccumulation and biomarkers were assessed in all three Mytilus species following a 4 day and a 21 day exposure to waterborne copper concentrations (0, 10, 100 and 500μg/L). Differences in copper bioaccumulation were measured after both 4 and 21 days, which suggests some physiological differences between the species. Furthermore, differences in response for some of the biological effects endpoints were also found to occur following exposure. These differences were discussed in relation to either real physiological differences between the species or merely confounding factors relating to the species natural habitat and seasonal cycles. Overall the study demonstrated that differences in chemical bioaccumulation and biomarker responses between the Mytilus spp. occur with potential consequences for mussel exposure studies and biological effects monitoring programmes. Consequently, the study highlights the importance of identifying the correct species when using Mytilus in biological effects studies.

  5. Determination of Two Diarrhetic Shellfish Poisons Residues in Mytilus edulis Linnaeus by High Performance Liquid Chromatography Tandem Mass Spectrometry%高效液相色谱-串联质谱法测定贻贝中腹泻性贝类毒素的含量

    Institute of Scientific and Technical Information of China (English)

    张海琪; 何欣; 郑重莺

    2012-01-01

    Establish the detection method of okadaic acid(OA) and dinophysistoxins(DTX-1) in Mytilus edulis using high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).Shellfish sample was extracted by 80% methyl.Shellfish extract solution was clean-up by Sep-pak silica column.A triple-quadrupole tandem mass spectrometer was used as a detector for HPLC to determine OA.As for the MS/MS,the multi-reactions monitoring(MRM) scan type and the negative ion electrospray ionization(-ESI) mode were applied.The precursor ion→product ion(m/z 803.5→m/z 255.1,m/z 803.5→m/z 563.1) was selected as OA quantitate detection ion pair.The precursor ion→product ion(m/z 817.4→m/z 255.1,m/z 817.4→m/z 113.1) was selected as DTX-1 quantitate detection ion pair.The mobile phase of HPLC was the methyl cyanide: 1% methanoic acid-water(vol/vol: 70:30) and the chromatographic column was Zorbax XDB-C18(2.1mm×150mm×5μm).The standard OA and DTX-1,the shellfish being added with OA and DTX-1,the shellfish sample were determine by the HPLC-MS/MS.The standard curve for OA showed good linearity over the concentration range of 5~640 ng/ml,the equation of linear regression was Y =207X-241(Q1/Q3:m/z 803.5→255.1),r was 0.9998,The recovery of sample being added with OA was 79.5%~88.6% and the RSD was 8.43%~10.4%.The standard curve for DTX-1 showed good linearity over the concentration range of 0 ~ 200 ng/ml,the equation of linear regression was Y =141X +3.59×103(Q1 /Q3: m / z817.4→255.1),r was 0.9997,The recovery of sample being added with DTX-1 was83.8%~91.2% and the RSD was 4.22%~6.54%.This HPLC-MS/MS is highly sensitive,fast,and very accurate.So it can be used for detecting the remain of OA and its natural derivative DTX-1 in shellfish.Among the 45 samples from the origin and market,4 samples were detected DSP,the ratio was 8.9%.%采用液相色谱-串联质谱法检测了贻贝中大田软

  6. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Science.gov (United States)

    Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

    2015-01-01

    Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

  7. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Directory of Open Access Journals (Sweden)

    George G Waldbusser

    Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

  8. 双壳类线粒体基因组结构分析%Analysis of Mitochondrial Genomic Structures in Bivalves

    Institute of Scientific and Technical Information of China (English)

    孟学平; 申欣; 赵娜娜; 田美; 郑立波; 程汉良; 阎斌伦; 董志国

    2013-01-01

    chain ,and mitochondrial genes from Unionoida in the 2 chains. A few species (12 species from Unionoida ,2 species from Veneroida ,1 species from Mytiloida ,and 1 species from Myoida , species from oyster Crassostrea) mitochondrial genomes contain 13 protein-coding genes (PCGs) ,and the remainings are comprised of 12 PCGs ,w hich are lack of AT P8 gene. The gene arrangements of PCGs and rRNAs are identical within same genus or family ,including 4 species from Meretrix ,4 species from Crassostrea ,11 species from Unionidae and Margaritiferidae , two species (Mytilus edulis and M. galloprovincialis) from mussel Mytilus. The gene arrangements of 10 mitochondrial genomes from Ostreidae can be divided into 7 types. There were no shared gene blocks in mitochondrial genomes from Pectinidae except similar gene structures were detected in bay scallop Argopecten irradians irradians f arreri(NC_012977)and A. irradians(NC_009687). The mussels Mytilus edulis and M. trossulus from Mytilidae have very similar genomic structures ,and the genomic structure of Musculista senhousia is very special with a duplicated cox2 genes. The gene arrangement of Hiatella arctica from Myoida is very different from other species. The proportions of non-coding regions in mitogenomes are ranged from 7.6%to 40.3% ,the major non-coding region ranging from 374nt to 4341nt in size in bivalves. The minimum divergence is found to be 0.2-1.0/0-1.0 in Meretrix ,0.4-2.0/0-3.2 in Mytilus and 1.9-13.9/0-6.4 in oyster Crassostrea based on nucleotides of PCGs genes/amino acids of proteins.

  9. Genes of the mitochondrial apoptotic pathway in Mytilus galloprovincialis.

    Directory of Open Access Journals (Sweden)

    Noelia Estévez-Calvar

    Full Text Available Bivalves play vital roles in marine, brackish, freshwater and terrestrial habitats. In recent years, these ecosystems have become affected through anthropogenic activities. The ecological success of marine bivalves is based on the ability to modify their physiological functions in response to environmental changes. One of the most important mechanisms involved in adaptive responses to environmental and biological stresses is apoptosis, which has been scarcely studied in mollusks, although the final consequence of this process, DNA fragmentation, has been frequently used for pollution monitoring. Environmental stressors induce apoptosis in molluscan cells via an intrinsic pathway. Many of the proteins involved in vertebrate apoptosis have been recognized in model invertebrates; however, this process might not be universally conserved. Mytilus galloprovincialis is presented here as a new model to study the linkage between molecular mechanisms that mediate apoptosis and marine bivalve ecological adaptations. Therefore, it is strictly necessary to identify the key elements involved in bivalve apoptosis. In the present study, six mitochondrial apoptotic-related genes were characterized, and their gene expression profiles following UV irradiation were evaluated. This is the first step for the development of potential biomarkers to assess the biological responses of marine organisms to stress. The results confirmed that apoptosis and, more specifically, the expression of the genes involved in this process can be used to assess the biological responses of marine organisms to stress.

  10. Recombinant mitochondrial genome with standard transmission route from Mediterranean mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Śmietanka, Beata; Filipowicz, Monika; Burzyński, Artur

    2016-01-01

    Several bivalve species, including marine mussels Mytilus are atypical in having two gender-specific and highly divergent mtDNA genomes. This peculiar genetic system allows not only the recombination to occur but also facilitates its detection. Previous reports associated the existence of mosaic recombinant haplotypes with the switch of their transmission route. Here we report nearly complete sequence of a mitochondrial genome isolated from a homoplasmic female individual of Mediterranean Mytilus galloprovincialis. The genome has clear phylogenetic affinity with and organization identical to the M. galloprovincialis female haplotypes, in the coding part. However, the genome is very large, approximately 20,600 bp long, exclusively due to a long and complex control region. It contains an array of repeats, some of which are degenerated. A large part of the control region is derived from the paternal genome. This finding shows that not all haplotypes with recombinant control regions must be paternally inherited in Mytilus.

  11. The health status of mussels, Mytilus spp., in Ireland and Wales with the molecular identification of a previously undescribed haplosporidian.

    Science.gov (United States)

    Lynch, S A; Morgan, E; Carlsson, J; Mackenzie, C; Wooton, E C; Rowley, A F; Malham, S; Culloty, S C

    2014-05-01

    Both wild and cultured mussels (Mytilus edulis, Mytilus galloprovincialis and hybrids), are found along most of the Irish coastline. M. edulis is widespread along all Irish coasts and is the only mussel species present on both the east coast of Ireland and the Welsh coast in the Irish Sea. M. galloprovincialis and hybrids are found along the Irish coastline except for the east coast. Samples of Mytilus spp. were collected from twenty-four sites, encompassing all coasts of Ireland and the Welsh coast, at different times of the year and over several years (2008-2011). In total, 841 mussels were examined histologically to assess their health status and the presence of any parasites or commensals. Mussels from 14 of the 24 sites were screened using polymerase chain reaction (PCR) to determine which mytilid species were present. A range of parasites were observed, generally at low levels. The most diverse community of parasites was observed at a sheltered site with poor water quality. Of significance, a previously undescribed haplosporidian was detected in a single mussel sample in the Menai Strait, Wales, by PCR and was confirmed by direct sequencing and is most closely related to Minchina chitonis and a haplosporidian of the Florida marsh clam Cyrenoida floridana. While M. edulis were infected by a variety of micro- and macro-parasites, only trematodes were observed in M. galloprovincialis and hybrids. Habitat description and the environmental factors influencing the study sites, including water quality and exposure, were recorded.

  12. Can bivalve veligers escape feeding currents of adult bivalves?

    NARCIS (Netherlands)

    Troost, K.; Veldhuizen, R.; Stamhuis, E.J.; Wolff, W.

    2008-01-01

    While the stock of introduced Pacific oysters (Crassostrea gigas) increased in the Oosterschelde estuary (SW Netherlands), so did the filtration pressure of all bivalve species together. In the same period, stocks of native bivalves declined slightly. The expansion of Pacific oysters in Dutch estuar

  13. Insights into shell deposition in the Antarctic bivalve Laternula elliptica: gene discovery in the mantle transcriptome using 454 pyrosequencing

    Directory of Open Access Journals (Sweden)

    Power Deborah M

    2010-06-01

    ,084 Single Nucleotide Polymorphisms(SNPs/INDELS, providing a resource for population and also gene function studies. Conclusions This is the first 454 data from an Antarctic marine invertebrate. Sequencing of mantle tissue from this non-model species has considerably increased resources for the investigation of the processes of shell deposition and repair in molluscs in a changing environment. A number of promising candidate genes were identified for functional analyses, which will be the subject of further investigation in this species and also used in model-hopping experiments in more tractable and economically important model aquaculture species, such as Crassostrea gigas and Mytilus edulis.

  14. Recirculation nursery systems for bivalves

    NARCIS (Netherlands)

    Kamermans, P.; Blanco Garcia, A.; Joaquim, Sandra; Matias, Domitilia; Magnesen, Thorolf; Nicolas, J.; Petten, Bruno; Robert, Rene

    2016-01-01

    n order to increase production of bivalves in hatcheries and nurseries, the development of new technology and its integration into commercial bivalve hatcheries is important. Recirculation aquaculture systems (RASs) have several advantages: high densities of the species can be cultured resulting in

  15. First evidence of immunomodulation in bivalves under seawater acidification and increased temperature.

    Directory of Open Access Journals (Sweden)

    Valerio Matozzo

    Full Text Available Water acidification, temperature increases and changes in seawater salinity are predicted to occur in the near future. In such a global climate change (GCC scenario, there is growing concern for the health status of both wild and farmed organisms. Bivalve molluscs, an important component of coastal marine ecosystems, are at risk. At the immunological level, the ability of an organism to maintain its immunosurveillance unaltered under adverse environmental conditions may enhance its survival capability. To our knowledge, only a few studies have investigated the effects of changing environmental parameters (as predicted in a GCC scenario on the immune responses of bivalves. In the present study, the effects of both decreased pH values and increased temperature on the important immune parameters of two bivalve species were evaluated for the first time. The clam Chamelea gallina and the mussel Mytilus galloprovincialis, widespread along the coast of the Northwestern Adriatic Sea, were chosen as model organisms. Bivalves were exposed for 7 days to three pH values (8.1, 7.7 and 7.4 at two temperatures (22 and 28°C. Three independent experiments were carried out at salinities of 28, 34 and 40 PSU. The total haemocyte count, Neutral Red uptake, haemolymph lysozyme activity and total protein levels were measured. The results obtained demonstrated that tested experimental conditions affected significantly most of the immune parameters measured in bivalves, even if the variation pattern of haemocyte responses was not always linear. Between the two species, C. gallina appeared more vulnerable to changing pH and temperature than M. galloprovincialis. Overall, this study demonstrated that climate changes can strongly affect haemocyte functionality in bivalves. However, further studies are needed to clarify better the mechanisms of action of changing environmental parameters, both individually and in combination, on bivalve haemocytes.

  16. Histopathological and apoptotic changes on marine mussels Mytilus galloprovincialis (Lamark, 1819) following exposure to environmental pollutants.

    Science.gov (United States)

    Yavaşoğlu, Altuğ; Özkan, Dilara; Güner, Adem; Katalay, Selma; Oltulu, Fatih; Yavaşoğlu, N Ülkü Karabay

    2016-08-15

    Marine bivalve mussels, especially Mytilus species are an earlywarning system used for determining of damage caused by the various aquatic pollutions. In the present study, Mytilus galloprovincialis L. (black mussel) have been utilised as a biomonitoring organism to reveal environmental pollution in the Aliaga, Foca and Urla where located along the Izmir Coast of Turkey. Mussels were collected at these areas and gill and hepatopancreas (digestive gland) tissues were excised. mRNA expressions of initiator (caspase-2 and -8) and executioner (caspase -3/7-1, -3/7-2, -3/7-3 and -3/7-4) caspases of mussels tissues in areas exposed to pollution agent have been observed. TUNEL immunoreactivity in paralel to histopathological changes in both Aliaga and Foca areas were compared with Urla. This study is the first report to reveal the pollution with apoptotic expression on mussels in the coast of Turkey.

  17. MICROBIOLOGICAL ASSESSMENT OF MUSSELS (MYTILUS GALLOPROVINCIALIS FARMED AND COMMERCIALIZED IN CAMPANIA REGION

    Directory of Open Access Journals (Sweden)

    N. Costanzo

    2011-01-01

    Full Text Available Mytilus galloprovincialis is one of the most commonly consumed bivalve molluscs. Several samples of Mytilus galloprovincialis were collected from different sea farms or bought in retail shops and from irregular peddlers. Total Mesophilic and Psicrophilic Aerobic Bacteria, Enterobatteriacee, E. coli, Salmonella spp., Vibrio spp. and L. monocytogenes were researched following ISO methods and EU Regulations. In mussels taken from the farms the limits were higher than those established by EU Regulation 2073/2005 only in one sample for E.coli and one for Salmonella spp. The mussels bought in retail shops showed good results and no sample exceed the law limits. Only one sample collected from irregular peddlers showed high levels of E.coli.

  18. Seasonal changes in functional parameters of the hemolymph of Mytilus galloprovincialis

    Directory of Open Access Journals (Sweden)

    C Ciacci

    2009-04-01

    Full Text Available n bivalves, many functional parameters show seasonal changes in relation to both abiotic (such as temperature and salinity and biotic factors (such as gonad maturation, food availability. Available data indicate that also immune parameters can show seasonal fluctuations in the marine mussel Mytilus spp.. In this work we report data on hemocyte lysosomal membrane stability (LMS and phagocytic activity, as well as on soluble lysozyme activity, in the hemolymph of mussels (Mytilus galloprovincialis collected over a 24 month period in the Adriatic Sea (2006-2007. The results indicate that all the parameters measured show seasonal fluctuations over the year, with lysozyme activity showing the largest changes. Lowest LMS values were observed in early winter and early autumn, whereas maximal values of phagocytic activity were observed in winter and increasing serum lysozyme activities were recorded in autumn. The observed seasonal fluctuations are discussed in relation to both abiotic (temperature and biotic (changes in endogenous modulators factors.

  19. Micropropagation of Alibertia edulis Rich

    Directory of Open Access Journals (Sweden)

    Fernanda Augusta Boato da Silva

    2008-12-01

    Full Text Available The aim of this work was to develop a micropropagation protocol for Alibertia edulis, a medicinal Brazilian Cerrado plant. A. edulis seeds were sterilized and germinated in water-agar. Fifteen millimeter long explants from the seedlings cultivated for 50 days were used for the multiplication in three consecutive subcultures. The cytokinin benzyladenine (BA alone or combined with indole-3-butyric acid (IBA was added to ¼ MS medium. The treatments containing combinations of the BA + IBA induced more shoot proliferation than the BA alone, with the optimum concentration of 0.5 mg.L-1 for both growth regulators. A. edulis shoots elongated easily and the presence of growth regulators did have a positive effect on the shoot elongation. Consecutive subcultures also had a positive effect on both sprouting and shoot elongation. Activated charcoal was essential for rooting, and all rooted plants were able to acclimatize.Foi desenvolvido um protocolo de micropropagação para A. edulis, uma espécie arbórea frutífera e medicinal presente no Cerrado brasileiro. Sementes de A. edulis foram esterilizadas e germinadas em ágar-água. Explantes de 15 mm foram retirados das plântulas e cultivados por 50 dias em meio de multiplicação e três subculturas. A citocinina benzilalanina (BA, sozinha ou em combinação com ácido indol butírico (IBA foram adicionados em no meio ¼ MS. Os tratamentos contendo combinações de BA-IBA induziram uma maior proliferação de brotos que aqueles somente com BA, e a concentração ótima desses reguladores de crescimento foi de 0.5 mg.L-1 para cada. Os brotos de A. edulis facilmente se alongaram e a presença de reguladores de crescimento no meio de cultura teve efeito positivo sobre o alongamento. Da mesma forma, as consecutivas subculturas tiveram um efeito positivo tanto sobre a brotação quanto no alongamento. Carvão ativado foi essencial para o enraizamento dos ramos, e todas as plantas foram aclimatadas com sucesso.

  20. Studies on filtration rate in four species of suspension feeding bivalves

    Institute of Scientific and Technical Information of China (English)

    林元烧; 罗文新; 曹文清; 郭东晖; 郑爱榕; 黄长江

    2002-01-01

    The filtration rates of four kinds of bivalves that were cultivated dominantly around Xiamen sea area were measured by using a laboratory flowing system. The experimental results were shown below: (1) Filtration rates were measured in the range of 54~74.8 ml/ (g@min) among the four bivalves, sequencing descently Saccostrea cucullata > Sinonovacula constricta > Mytilus viridis > Ruditapes philippinarum. (2) The relationship between filtration rates on individual size showed a negative exponential function (FR = aWb, FR' = aWb-1), with b - 1 = - 0.435 6 and - 0.392. (3) Filtration rates on Skeletonema costatum were much higher than on Alexandrium tamarensis and Scrippsilla trochoidea inS. Cucullata and R. Philippinarum. (4) FR'on algal densities was also shown a negative function(FR' = aDb-1), with b-1 =-0.143 and-0.215 2 in S.cucullata and R.philippinarum, respectively.

  1. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three di

  2. Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

    Directory of Open Access Journals (Sweden)

    Tiziana Tedde

    2013-06-01

    Full Text Available Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oocysts, and are responsible for enteritis in several animal species and humans worldwide. These (oocysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i staining for light and fluorescence microscopy; ii direct immunofluorescence (IF Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA; and iii molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas.

  3. Complete mitochondrial DNA sequence of the European flat oyster Ostrea edulis confirms Ostreidae classification

    Directory of Open Access Journals (Sweden)

    Morga Benjamin

    2011-10-01

    Full Text Available Abstract Background Because of its typical architecture, inheritance and small size, mitochondrial (mt DNA is widely used for phylogenetic studies. Gene order is generally conserved in most taxa although some groups show considerable variation. This is particularly true in the phylum Mollusca, especially in the Bivalvia. During the last few years, there have been significant increases in the number of complete mitochondrial sequences available. For bivalves, 35 complete mitochondrial genomes are now available in GenBank, a number that has more than doubled in the last three years, representing 6 families and 23 genera. In the current study, we determined the complete mtDNA sequence of O. edulis, the European flat oyster. We present an analysis of features of its gene content and genome organization in comparison with other Ostrea, Saccostrea and Crassostrea species. Results The Ostrea edulis mt genome is 16 320 bp in length and codes for 37 genes (12 protein-coding genes, 2 rRNAs and 23 tRNAs on the same strand. As in other Ostreidae, O. edulis mt genome contains a split of the rrnL gene and a duplication of trnM. The tRNA gene set of O. edulis, Ostrea denselamellosa and Crassostrea virginica are identical in having 23 tRNA genes, in contrast to Asian oysters, which have 25 tRNA genes (except for C. ariakensis with 24. O. edulis and O. denselamellosa share the same gene order, but differ from other Ostreidae and are closer to Crassostrea than to Saccostrea. Phylogenetic analyses reinforce the taxonomic classification of the 3 families Ostreidae, Mytilidae and Pectinidae. Within the Ostreidae family the results also reveal a closer relationship between Ostrea and Saccostrea than between Ostrea and Crassostrea. Conclusions Ostrea edulis mitogenomic analyses show a high level of conservation within the genus Ostrea, whereas they show a high level of variation within the Ostreidae family. These features provide useful information for further

  4. P-glycoprotein and its inducible expression in three bivalve species after exposure to Prorocentrum lima.

    Science.gov (United States)

    Huang, Lu; Liu, Su-Li; Zheng, Jian-Wei; Li, Hong-Ye; Liu, Jie-Sheng; Yang, Wei-Dong

    2015-12-01

    P-glycoprotein (P-gp or ABCB1) belongs to the family of ATP-binding cassette (ABC) transporters responsible for multixenobiotic resistance (MXR) in aquatic organisms. To provide more information of P-gp in shellfish, in this study, complete cDNA of P-gp in three bivalve species including Ruditapes philippinarum, Scapharca subcrenata and Tegillarca granosa were cloned and its expressions in gill, digestive gland, adductor muscle and mantle of the three bivalves were detected after exposure to Prorocentrum lima, a toxogenic dinoflagellate. The complete sequences of R. philippinarum, S. subcrenata and T. granosa P-gp showed high homology with MDR/P-gp/ABCB proteins from other species, having a typical sequence organization as full transporters from the ABCB family. Phylogenetic analyses revealed that the amino acid sequences of P-gp from S. subcrenata and T. granosa had a closest relationship, forming an independent branch, then grouping into the other branch with Mytilus californianus, Mytilus galloprovincialis and Crassostrea gigas. However, P-gp sequences from R. philippinarum were more similar to the homologs from the more distantly related Aplysia californica than to homologs from S. subcrenata and T. granosa, suggesting that bivalves P-gp might have different paralogs. P-glycoprotein expressed in all detected tissues but there were large differences between them. After exposure to P. lima, the expression of P-gp changed in the four tissues in varying degrees within the same species and between different species, but the changes in mRNA and protein level were not always synchronous.

  5. Trace element ratios in bivalve shells as records of environmental conditions

    Science.gov (United States)

    Tynan, S.; Opdyke, B.; Welch, S.; Beavis, S.

    2007-12-01

    Stable isotope and trace element data from the carbonate of both marine and freshwater bivalves are proving to be useful tools in studies of palaeoclimate and environmental change. However, much of the work already done has shown that the trace element ratios in bivalve shells exhibit a complex relationship with the ambient environment and caution must be exercised when attempting to use them as environmental proxies. This work examines the feasibility of using the trace element ratios Mg/Ca, Sr/Ca, Ba/Ca and Mn/Ca of the shells of a number of different species of bivalves as records of the temperature and salinity of their ambient aquatic environment. The species analysed were the estuarine oysters Saccostrea glomerata, Ostrea angasi, and Crassostrea gigas, an estuarine mussel, Mytilus galloprovincialis, and the freshwater mussel Velesunio ambiguus. The estuarine shells were taken from monitoring experiments conducted over a period of 12 months at two different field sites. Freshwater shells were collected wild, from locations close to water monitoring stations. Preliminary results show distinct variations in the Mg/Ca of O. angasi shells with an apparent seasonal pattern. V. ambiguus shells show clear patterns in Mn/Ca, linked to environmental variations.

  6. Galeommatid bivalves from Phuket, Thailand

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Nielsen, Claus

    2005-01-01

    Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established. The spec......Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established...... crustacean, the remainder hide under shale, rocks and coral blocks, often in small intra- or interspecific family flocks. The behaviour was also noted for some of the species. It is presumed that galeommatid species go through a lengthy planktonic phase....

  7. Aggregation and attachment responses of blue mussels, Mytilus edulis—impact of substrate composition, time scale and source of mussel seed

    DEFF Research Database (Denmark)

    Christensen, Helle Torp; Dolmer, Per; Hansen, Benni Winding

    2015-01-01

    Survival after transplantation of mussel seeds is crucial for the production output of blue mussels (Mytilus edulis L.) in bottom cultures. Hence, an understanding of the interactions between bed formation, habitat structure and performance of mussel seed of different origins can contribute...... to an optimization of the production. The effect of substrate composition and timing of formation of a mussel bed in relation to aggregation and attachment of mussels were investigated with mussel seeds obtained from two different sources: mussel seed dredged from a natural mussel bed and mussel seed collected from...

  8. Biologically induced deposition of fine suspended particles by filter-feeding bivalves in land-based industrial marine aquaculture wastewater.

    Science.gov (United States)

    Zhou, Yi; Zhang, Shaojun; Liu, Ying; Yang, Hongsheng

    2014-01-01

    Industrial aquaculture wastewater contains large quantities of suspended particles that can be easily broken down physically. Introduction of macro-bio-filters, such as bivalve filter feeders, may offer the potential for treatment of fine suspended matter in industrial aquaculture wastewater. In this study, we employed two kinds of bivalve filter feeders, the Pacific oyster Crassostrea gigas and the blue mussel Mytilus galloprovincialis, to deposit suspended solids from marine fish aquaculture wastewater in flow-through systems. Results showed that the biodeposition rate of suspended particles by C. gigas (shell height: 8.67 ± 0.99 cm) and M. galloprovincialis (shell height: 4.43 ± 0.98 cm) was 77.84 ± 7.77 and 6.37 ± 0.67 mg ind(-1) • d(-1), respectively. The total solid suspension (TSS) deposition rates of oyster and mussel treatments were 3.73 ± 0.27 and 2.76 ± 0.20 times higher than that of the control treatment without bivalves, respectively. The TSS deposition rates of bivalve treatments were significantly higher than the natural sedimentation rate of the control treatment (P aquaculture wastewater, and simultaneously yield value-added biological products.

  9. Sequence analysis of novel CYP4 transcripts from Mytilus galloprovincialis.

    Science.gov (United States)

    Ravlić, Sanda; Žučko, Jurica; Tanković, Mirta Smodlaka; Fafanđel, Maja; Bihari, Nevenka

    2015-07-01

    Cytochrome P450 enzymes (CYPs) are essential components of cellular detoxification system. We identified and characterized seven new cytochrome P450 gene transcript clusters in the populations of bivalve mollusc Mytilus galloprovincialis from three different locations. The phylogenetic analysis identified all transcripts as clusters within the CYP4 branch. Identified clusters, each comprising a number of transcript variants, were designated CYP4Y1, Y2, Y3, Y4, Y5, Y6 and Y7. Transcript clusters CYP4Y2 and Y7, and CYP4Y5 and Y6 showed site specificity, while the transcript clusters CYP4Y1, Y3 and Y4 were present at all investigated locations. The comparison of transcripts deduced amino acid sequences with CYP4s from vertebrate and invertebrate species showed high conservation of the residues and domains essential to the putative function of the enzyme, as terminal ω-hydroxylation and prostaglandin hydroxylation. Our results suggest the great expansion of the CYP4Y cDNAs indicative of CYP4 proteins in the mussel M. galloprovincialis presumably as a response to different environmental conditions.

  10. Sperm proteome of Mytilus galloprovincialis: Insights into the evolution of fertilization proteins in marine mussels.

    Science.gov (United States)

    Zhang, Yanjie; Mu, Huawei; Lau, Stanley C K; Zhang, Zhifeng; Qiu, Jian-Wen

    2015-12-01

    Cataloging the sperm proteome of an animal can improve our understanding of its sperm-egg interaction and speciation, but such data are available for only a few free-spawning invertebrates. This study aimed to identify the sperm proteome of Mytilus galloprovincialis, a free-spawning marine mussel. We integrated public transcriptome datasets by de novo assembly, and applied SDS-PAGE coupled LC-MS/MS analysis to profile the sperm proteome, resulting in the identification of 550 proteins. Comparing the homologous sperm protein coding genes between M. galloprovincialis and its closely related species M. edulis revealed that fertilization proteins have the highest mean nonsynonymous substitution rate (Ka/Ks = 0.62) among 11 functional groups, consistent with previous reports of positive selection of several fertilization proteins in Mytilus. Moreover, 78 sperm proteins in different functional groups have Ka/Ks values > 0.5, indicating the presence of many candidate sperm proteins for further analysis of rapid interspecific divergence. The MS data are available in ProteomeXchange with the identifier PXD001665.

  11. The production of relaid blue mussels ( Mytilus edulis L.) in a Danish fjord

    DEFF Research Database (Denmark)

    Kristensen, Per Sand; Lassen, H.

    1997-01-01

    based on samples from commercial landings in Limfjorden. The calculated harvest was compared to the observed yield from two commercial culture beds. The productivity in kg m(-2) in a bed of relaid mussels was found to be 2-7 times higher than in natural mussel beds in Limfjorden. (C) 1997 International...

  12. Area-intensive bottom culture production of blue mussels, Mytilus edulis (L.)

    DEFF Research Database (Denmark)

    Christensen, Helle Torp

    it is therefore necessary to focus on area-intensive production methods for mussel exploitation. For that purpose bottom culture production of blue mussels is relevant. Despite a long tradition for bottom culturing in Europe the method is still de-pendent on natural conditions, such as recruitment, food...... insights in biological mechanisms can be used as a tool to develop and optimize bottom culture production methods. The study was addressed through the following questions: 1) How can the seed mussel source in bottom culturing be supported? 2) How can survival of mussels in bottom culturing be improved...... column have the potential to become an alternative seed source for mussel production in bottom cultures. When compared to mussels collected from natural benthic mussel beds, suspended mussels had an active predator response by developing a significantly stronger attach-ment to the substrate and having...

  13. Short-term impact of blue mussel dredging ( Mytilus edulis L.) on a benthic community

    DEFF Research Database (Denmark)

    Dolmer, Per; Kristensen, T.; Christiansen, M.L.

    2001-01-01

    outside the mussel beds just after dredging, but this effect lasted for less than 7 days. After dredging, brown shrimps, C. crangon invaded the dredged areas. This species is an important predator of smaller invertebrates, and it is suspected that it was feeding on small vulnerable polychaetes exposed...... to the boundary area. This indicates that the disturbance of the mussel bed structure reduced growth and that the lowering of intraspecific food competition caused by a reduced density of mussels did not increase the accumulation of biomass in the mussels which remained in the dredged area.......The short-term effect of mussel dredging in a brackish Danish sound was studied. A commercial dredging track was identified and an analysis of the species composition inside the track and at an adjacent control area showed that dredging changed the community structure by reducing the density...

  14. Biomixing in stagnant wate above population of blue mussels (Mytilus edulis)

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Andrup, P.; Tang, B.

    2016-01-01

    Dense beds of filter-feeding mussels can exert a considerable grazing impact on phytoplankton in many marine areas depending on downmixing promoted by current, wave- and wind action. But downmixing may also be promoted by biomixing caused by the action of the strong exhalent jets of water from......% of the initial level after 120 min, which implied a population filtration rate of about 0.3 m3.h-1.m-2 in agreement with prior clearance measurements. Comparing to numerical solutions of a one-dimensional diffusion model, varying the eddy diffusivity, a value of D = 550 × 10-6 m2.s-1 was estimated. This high...

  15. Impact of elevated pCO2 on the ecophysiology of Mytilus edulis

    OpenAIRE

    Thomsen, Jörn

    2012-01-01

    Increasing atmospheric CO2 concentrations equilibrate with the surface water of the oceans and thereby increase seawater pCO2 and decrease [CO32-] and pH. This process of ocean acidification is expected to cause a drastic change of marine ecosystem composition and a decrease in calcification ability of various benthic invertebrates. The studied area, Kiel Fjord, is characterized by high pCO2 variability due to upwelling of O2 depleted and CO2 enriched bottom water. Within less than 50 years, ...

  16. Effects of nanopolystyrene on the feeding behavior of the blue mussel (Mytilus edulis L.)

    NARCIS (Netherlands)

    Wegner, A.; Besseling, E.; Foekema, E.M.; Kamermans, P.; Koelmans, A.A.

    2012-01-01

    As the industrial production of nanoplastic and the degradation of microplastic into smaller particles at sea increase, the potential amount of nanoplastics in the marine environment rises. It has been reported that mussels uptake 100-nm polystyrene (PS) beads; to date, however, the effects of this

  17. Blue mussel (Mytilus edulis) growth at various salinity regime determined by a Dynamic Energy Budget model

    DEFF Research Database (Denmark)

    Saurel, Camille; Maar, Marie; Landes, Anja

    such as food supply, temperature and salinity. In the Baltic Sea - highly disturbed eutrophied environment-mussel growth efficiency is limited due to the very low levels of salinity and in area where the salinity is below 8 psu, mussels appear on a dwarf form. The aim of the present study was to incorporate...... the effects of low salinity into an eco-physiological model of blue mussels and to identify areas suitable for cost-effective mussel production for mitigation culture. A standard Dynamic Energy Budget (DEB) model was modified with respect to i) the morphological parameters (DW/WW-ratio, shape factor), ii......) change in ingestion rate and iii) metabolic costs due to osmotic regulatory mechanisms to adapt in different salinity environments. The modified DEB model was validated with experimental data from different locations in the Western Baltic Sea including the Limfjorden, with salinities ranging from 8...

  18. Histochemical and structural analysis of mucous glycoprotein secreted by the gill of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Hae-Young.

    1988-01-01

    Studies were carried out to characterized various mucous cells in the gill filament, to ascertain structural characteristics of the secreted mucous glycoproteins, and to determine the ability of the gill epithelium to incorporate ({sup 14}C)glucosamine as a precursor in the biosynthesis and secretion of mucous glycoproteins. Using histochemical staining techniques, mucous cells containing neutral and acidic mucins were found in the lateral region, whereas mucous cells containing primarily neutral or sulfated mucins were found in the postlateral region. Serotonin, but not dopamine, stimulated the mucous secretion. In tissues pretreated with ({sup 14}C)glucosamine, the secreted glycoproteins contain incorporated radiolabel. Analysis by column chromatography using Bio-Gel P-2 and P-6 shows that the secretion contains two glycoprotein populations. Glycoprotein II has a molecular weight of 2.3 {times} 10{sup 4} daltons. Upon alkaline reductive borohydride cleavage of the O-glycosidic linkages of glycoprotein I, about 70% of the radiolabel was removed from the protein. Gas chromatographic analysis of the carbohydrate composition shows that the glycoproteins contains N-acetylglucosamine (GluNAc), N-acetylgalactosamine (GalNAc), and galactose, fucose and mannose. Amino acid analysis shows that the glycoproteins are rich in serine, threonine and proline.

  19. Oxygen isotope ratios in the shell of Mytilus edulis: Archives of glacier meltwater in Greenland?

    DEFF Research Database (Denmark)

    Versteegh, E.A.A.; Blicher, M.E.; Mortensen, J.

    2012-01-01

    Melting of the Greenland Ice Sheet (GrIS) is accelerating and will contribute significantly to global sea level rise during the 21st century. Instrumental data on GrIS melting only cover the last few decades, and proxy data extending our knowledge into the past are vital for validating models...

  20. The utilization of glycogen and accumulation of some intermediates during anaerobiosis in Mytilus edulis L.

    NARCIS (Netherlands)

    Zwaan, A.; Zandee, D.I.

    1972-01-01

    1. 1. Glycogen degradation in the mussel under anaerobic conditions was measured at two temperatures. Glycogen decrease at 6·6°C was about 3 mg and at 20°C about 6 mg/24 hr per mussel. A Pasteur effect was observed. 2. 2. The decrease of glycogen was almost entirely restricted to muscles, including

  1. Does the antibiotic amoxicillin affect haemocyte parameters in non-target aquatic invertebrates? The clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis as model organisms.

    Science.gov (United States)

    Matozzo, Valerio; Bertin, Valeria; Battistara, Margherita; Guidolin, Angelica; Masiero, Luciano; Marisa, Ilaria; Orsetti, Alessandro

    2016-08-01

    Amoxicillin (AMX) is one of the most widely used antibiotics worldwide, and its levels in aquatic ecosystems are expected to be detectable. At present, information concerning the toxic effects of AMX on non-target aquatic organisms, such as bivalves, is scarce. Consequently, in this study, we investigated for the first time the effects of AMX on the haemocyte parameters of two bivalve species, the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis, which share the same habitat in the Lagoon of Venice, in order to compare the relative sensitivity of the two species. The bivalves were exposed to 100, 200 and 400 μg AMX/L for 1, 3 and 7 days, and the effects on the total haemocyte count (THC), the diameter and volume of the haemocytes, haemocyte proliferation, lactate dehydrogenase (LDH) activity in cell-free haemolymph, the haemolymph pH, and the formation of micronuclei were evaluated. The actual concentrations of AMX in the seawater samples from the experimental tanks were also measured. Overall, the obtained results demonstrated that AMX affected slightly the haemocyte parameters of bivalves. In addition, no clear differences in terms of sensitivity to AMX exposure were recorded between the two bivalve species.

  2. Geographic and seasonal patterns and limits on the adaptive response to temperature of European Mytilus spp. and Macoma balthica populations.

    Science.gov (United States)

    Jansen, Jeroen M; Pronker, Annelies E; Kube, Sandra; Sokolowski, Adam; Sola, J Carlos; Marquiegui, Mikel A; Schiedek, Doris; Wendelaar Bonga, Sjoerd; Wolowicz, Maciej; Hummel, Herman

    2007-11-01

    Seasonal variations in seawater temperature require extensive metabolic acclimatization in cold-blooded organisms inhabiting the coastal waters of Europe. Given the energetic costs of acclimatization, differences in adaptive capacity to climatic conditions are to be expected among distinct populations of species that are distributed over a wide geographic range. We studied seasonal variations in the metabolic adjustments of two very common bivalve taxa at European scale. To this end we sampled 16 populations of Mytilus spp. and 10 Macoma balthica populations distributed from 39 degrees to 69 degrees N. The results from this large-scale comprehensive comparison demonstrated seasonal cycles in metabolic rates which were maximized during winter and springtime, and often reduced in the summer and autumn. Studying the sensitivity of metabolic rates to thermal variations, we found that a broad range of Q (10) values occurred under relatively cold conditions. As habitat temperatures increased the range of Q (10) narrowed, reaching a bottleneck in southern marginal populations during summer. For Mytilus spp., genetic-group-specific clines and limits on Q (10) values were observed at temperatures corresponding to the maximum climatic conditions these geographic populations presently experience. Such specific limitations indicate differential thermal adaptation among these divergent groups. They may explain currently observed migrations in mussel distributions and invasions. Our results provide a practical framework for the thermal ecophysiology of bivalves, the assessment of environmental changes due to climate change and its impact on (and consequences for) aquaculture.

  3. Genetic traits in the bivalve Mytilus from Europe, with an emphasis on Arctic populations

    NARCIS (Netherlands)

    Hummel, H.; Colucci, P.; Bogaards, R.H.; Strelkov, P.P.

    2001-01-01

    Genetic and some ecophysiological traits of mussels collected in the European Arctic, up to their northeastern distribution limit in the Barents Sea, were studied and compared with traits of mussels from the Mediterranean, Atlantic and Baltic. The genetic traits of these populations we-re analysed b

  4. Biologically induced deposition of fine suspended particles by filter-feeding bivalves in land-based industrial marine aquaculture wastewater.

    Directory of Open Access Journals (Sweden)

    Yi Zhou

    Full Text Available Industrial aquaculture wastewater contains large quantities of suspended particles that can be easily broken down physically. Introduction of macro-bio-filters, such as bivalve filter feeders, may offer the potential for treatment of fine suspended matter in industrial aquaculture wastewater. In this study, we employed two kinds of bivalve filter feeders, the Pacific oyster Crassostrea gigas and the blue mussel Mytilus galloprovincialis, to deposit suspended solids from marine fish aquaculture wastewater in flow-through systems. Results showed that the biodeposition rate of suspended particles by C. gigas (shell height: 8.67 ± 0.99 cm and M. galloprovincialis (shell height: 4.43 ± 0.98 cm was 77.84 ± 7.77 and 6.37 ± 0.67 mg ind(-1 • d(-1, respectively. The total solid suspension (TSS deposition rates of oyster and mussel treatments were 3.73 ± 0.27 and 2.76 ± 0.20 times higher than that of the control treatment without bivalves, respectively. The TSS deposition rates of bivalve treatments were significantly higher than the natural sedimentation rate of the control treatment (P < 0.001. Furthermore, organic matter and C, N in the sediments of bivalve treatments were significantly lower than those in the sediments of the control (P < 0.05. It was suggested that the filter feeders C. gigas and M. galloprovincialis had considerable potential to filter and accelerate the deposition of suspended particles from industrial aquaculture wastewater, and simultaneously yield value-added biological products.

  5. Genetic characterization of Mytilus coruscus and M. galloprovincialis using microsatellite markers.

    Science.gov (United States)

    Kang, J H; Lee, J M; Noh, E S; Park, J Y; An, C M

    2013-01-01

    Korean (hard-shelled) mussels (Mytilus coruscus) are an economically important endemic marine bivalve mollusk of Korea; yet, the population has rapidly declined because of overharvesting and habitat competition from the invasive Mytilus galloprovincialis species. The population structures of M. coruscus and M. galloprovincialis were analyzed by next-generation sequencing using 5 microsatellite markers specifically developed for M. coruscus. M. galloprovincialis had an average of 5.4 alleles per locus (range = 2-10), with an average allelic richness of 4.9 per locus (range = 2.0-9.3). M. coruscus had an average of 5.7 alleles per locus (range = 2-13), with an average allelic richness of 5.2 per locus (range = 2.0-11.9). Excessive homozygosity was observed at 3 loci, which was assumed to be due to the presence of null alleles at these loci. Pairwise multilocus FST estimates showed that the M. coruscus and M. galloprovincialis populations were clearly separated. Six populations of M. galloprovincialis from the western, eastern, and southern coast of Korea formed 2 separate clusters, indicating that more than 2 populations of M. galloprovincialis have been introduced to the Korean Peninsula. Hybrids between M. coruscus and M. galloprovincialis were not identified, probably because of genetic differences or different habitat preferences. Further genetic information is required to perform selective breeding, population management, and restoration of M. coruscus.

  6. Mercury concentration in bivalve molluscs

    Directory of Open Access Journals (Sweden)

    Szkoda Józef

    2015-09-01

    Full Text Available A total of 85 mussel samples of eight species were examined. Analysis of mercury in the freeze-dried samples was carried out by atomic absorption spectrometry method using direct mercury analyser AMA 254. The analytical procedure for determination of mercury was covered by the quality assurance programme of research and participation in national and international proficiency tests. Concentrations of total mercury in all investigated samples were found to be generally low, in the range of 0.033-0.577 mg/kg of dry weight and of 0.003-0.045 mg/kg of wet weight. The results indicate that obtained levels of mercury in bivalve molluscs are not likely to pose a risk to the health of consumers.

  7. Norovirus in bivalve molluscs: a study of the efficacy of the depuration system

    Directory of Open Access Journals (Sweden)

    Giovanni Savini

    2009-12-01

    Full Text Available Noroviruses are the most common viral agents of acute gastroenteritis in humans and are often associated with the consumption of either fresh or undercooked live bivalve molluscs. The aim of the study was to evaluate the efficacy of the water depuration systems in the presence of Norovirus contamination A total of 96 shellfish samples was examined by reverse transcriptase-polymerase chain reaction, as follows: 58 mussel samples (Mytilus galloprovincialis, 35 Manila clam samples (Tapes decussatus and 3 Pacific oyster samples (Crassostrea gigas. Of these, 67 were collected before and 29 following depuration. Viral RNA was detected in one of the 67 non-depurated samples examined (1.5%; 95% confidence interval: 0.36-7.92% and in one of the 29 depurated samples (3.4%; 95% confidence interval: 0.82-17.22%. There were no statistically significant differences between depurated and non-depurated samples which indicated that the purifying systems in place were not able to remove Norovirus contamination from the live bivalve molluscs.

  8. Polycyclic Aromatic Hydrocarbons in Sediments and Bivalves on the Pacific Coast of Japan: Influence of Tsunami and Fire

    Science.gov (United States)

    Onozato, Mayu; Nishigaki, Atsuko; Okoshi, Kenji

    2016-01-01

    Surface sediments and at least one edible bivalve species (Ruditapes philippinarum, Mytilus galloprovincialis, and Crassostrea gigas) were collected from each of seven intertidal sites in Japan in 2013. The sites had experienced varying levels of tsunami and fire disturbance following the major earthquake of 2011. Eight polycyclic aromatic hydrocarbons (PAHs) were identified and analyzed by gas chromatography–mass spectrometry. Total sediment PAH concentration (CT), the sum of the average concentrations of the eight PAHs, was 21–1447 μg kg-1-dry. Relative to the average level of one type of PAH in sediments collected around Japan in 2002 (benzo[a]pyrene = 21 μg kg-1-dry), five of the seven sites showed concentrations significantly lower than this average in 2013. The CTs for the three bivalves (134–450 μg kg-1-dry) were within the range of the previous reports (2.2–5335 μg kg-1-dry). The data suggest that the natural disaster did not increase PAH concentrations or affect the distribution within sediment or bivalves in Tohoku district. Although PAH concentrations at the sites pose no risk to human health, the findings highlight that the observed PAH levels derive from pre- rather than post-quake processes. PMID:27232189

  9. Polycyclic Aromatic Hydrocarbons in Sediments and Bivalves on the Pacific Coast of Japan: Influence of Tsunami and Fire.

    Directory of Open Access Journals (Sweden)

    Mayu Onozato

    Full Text Available Surface sediments and at least one edible bivalve species (Ruditapes philippinarum, Mytilus galloprovincialis, and Crassostrea gigas were collected from each of seven intertidal sites in Japan in 2013. The sites had experienced varying levels of tsunami and fire disturbance following the major earthquake of 2011. Eight polycyclic aromatic hydrocarbons (PAHs were identified and analyzed by gas chromatography-mass spectrometry. Total sediment PAH concentration (CT, the sum of the average concentrations of the eight PAHs, was 21-1447 μg kg-1-dry. Relative to the average level of one type of PAH in sediments collected around Japan in 2002 (benzo[a]pyrene = 21 μg kg-1-dry, five of the seven sites showed concentrations significantly lower than this average in 2013. The CTs for the three bivalves (134-450 μg kg-1-dry were within the range of the previous reports (2.2-5335 μg kg-1-dry. The data suggest that the natural disaster did not increase PAH concentrations or affect the distribution within sediment or bivalves in Tohoku district. Although PAH concentrations at the sites pose no risk to human health, the findings highlight that the observed PAH levels derive from pre- rather than post-quake processes.

  10. Persistent free radical ESR signals in marine bivalve tissues

    Energy Technology Data Exchange (ETDEWEB)

    Mehlorn, R.J. [California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering; Mendez, A.T. [Fundacion Educativa Ana G. Mendez, Rio Piedras (Puerto Rico); Higashi, R. [California Univ., Bodega Bay, CA (United States). Bodega Marine Lab.; Fan, T. [California Univ., Davis, CA (United States)

    1992-08-01

    Freeze-dried homogenates of the oyster Crassostrea rhizophorae collected from waters in Puerto Rico near urban and industrial sites as well as at relatively pristine locations yielded electron spin resonance (ESR) spectra characteristic of free radicals as well as spectral components of transition metal ions, dominated by manganese. The magnitudes of these ESR signals and the concentrations of trace elements (determined by X-ray fluorescence) varied considerably among oyster samples, masking any potential correlation with polluted waters. Laboratory studies were initiated to identify the factors controlling the magnitudes of the tissue free radical ESR signals. Another mollusc, Mytilus californianus collected at the Bodega Marine laboratory in northern California, was fractionated into goneds and remaining tissue. Freeze-dried homogenates of both fractions exhibited ESR signals that increased gradually with time. ESR signals were observed in freeze-dried perchloric acid (PCA) precipitates of the homogenates, delipidated PCA precipitates, and in chloroform extracts of these precipitates. Acid hydrolysis to degrade proteins to amino acids produced a residue, which yielded much larger ESR free radical signals after freeze-drying. Freshly thawed homogenates of Crassostrea rhizophorae also exhibited ESR signals. A laboratory model of copper stress in Crassostrea rhizophorae was developed to study the effect of this transition metal on dssue free radicals. Preliminary results suggested that sublethal copper exposure had little effect on tissue fire radicals, except possibly for a signal enhancement in an oyster fraction that was enriched in kidney granules. Since kidney granules are known to accumulate heavy metals in mussels and probably other marine bivalves, this signal enhancement may prove to be an indicator of free radical processes associated with heavy metal deposition in molluscs.

  11. Phenylpropanoid derivatives from edible canna, Canna edulis.

    Science.gov (United States)

    Yun, Young Sook; Satake, Motoyoshi; Katsuki, Shigeki; Kunugi, Akira

    2004-07-01

    Two phenylpropanoid sucrose esters were isolated from dry rhizomes of Canna edulis Ker Gawl., along with a known phenylpropanoid sucrose ester and four known phenylpropanoids. On the basis of analysis of spectroscopic data and chemical evidence, these two phenylpropanoid sucrose esters were shown to be 3-O-p-coumaroyl-6-O-feruloyl-beta-D-fructofuranosyl 6-O-acetyl-alpha-D-glucopyranoside and 3,6-di-O-p-coumaroyl-beta-D-fructofuranosyl 6-O-acetyl-alpha-D-glucopyranoside.

  12. Morphology, Structure of Dimorphic Sperm, and Reproduction in the Hermaphroditic Commensal Bivalve Pseudopythina tsurumaru (Galeommatoidea: Kellidae)

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Jespersen, Åse; Takahashi, Tohru

    2004-01-01

    Galeommatoide, commensal bivalve, reproduction, dimorphic sperm, sperm ultrastructure, spermatozeugma......Galeommatoide, commensal bivalve, reproduction, dimorphic sperm, sperm ultrastructure, spermatozeugma...

  13. Oxidative stress and bivalves: a proteomic approach

    Directory of Open Access Journals (Sweden)

    B McDonagh

    2008-09-01

    Full Text Available Bivalves are of major importance in aquatic ecology, aquaculture, are widely used as sentinel species in environmental toxicology and show remarkable plasticity to molecular oxygen. Excess reactive oxygen species (ROS arising from molecular oxygen can cause oxidative stress and this is also a consequence of exposure to many common environmental pollutants. Indices of oxidative stress have therefore found favor as biomarkers of exposure and effect in environmental toxicology. However, there is a growing body of literature on the use of discovery-led proteomics methods to detect oxidative stress in bivalves. This is because proteins absorb up to 70 % of ROS leading to complication of the proteome. This article explores the background to these developments and assesses the practice and future potential of proteomics in the study of oxidative stress in bivalves.

  14. Caracterización molecular de materiales cultivados de gulupa (Passiflora edulis f. edulis

    Directory of Open Access Journals (Sweden)

    Jairo Hernán Moreno-Osorio

    2009-12-01

    Full Text Available Molecular characterization of cultivated materials of gulupa (Passiflora edulis f. edulis. Objective. To evaluate through RAM(Random Amplified Microsatellites molecular markers the genetic diversity of cultivated materials of gulupa (Passiflora edulis f. edulis,collected in the departments of Boyacá, Cundinamarca and Huila. Materials and methods. Young and healthy leaves were collected fromcrop fields of gulupa for DNA extraction and characterization through RAM molecular markers, according to Hantula’s protocol (1996.Binary data of the type presence/absence were collected from the electrophoretic profiles. Data were analyzed with NTSYS- pc- 2.0statistical package, obtaining a similarity matrix using the Dice coefficient. Results. RAM markers were efficient in detecting polymorphismin this species. Four universal primers were used that produced 88.8% of polymorphism. In general terms, with the RAM molecularmarkers a high genetic diversity was detected in the areas where gulupa is cultivated in Colombia. In the present study no geographicalrelatedness was found with the accessions evaluated for department or locality. Conclusions. The materials of gulupa evaluated in thisstudy showed a high genetic diversity (0.291-1, probably due to the propagation method, its diverse provenances and the short time ofestablishment of the culture in Colombia.

  15. Assessment of the fitness of the mussel Mytilus galloprovincialis two years after the Hebei Spirit oil spill.

    Science.gov (United States)

    Donaghy, Ludovic; Hong, Hyun-Ki; Kim, Moonkoo; Park, Heung-Sik; Choi, Kwang-Sik

    2016-12-15

    In December 2007, >150km of the West coast of Korea were heavily polluted by crude oil leaked from the oil tanker Hebei Spirit, leading to mass mortality of bivalve mollusks on the intertidal areas. Two years after, mussels Mytilus galloprovincialis were collected from two impacted sites to investigate sub-lethal effects of the oil spill. Tissue content in polycyclic aromatic hydrocarbons (PAHs), hemocyte parameters, reproductive status and energetic reserves were analyzed. PAHs in tissues of mussels as well as hemocyte parameters were not different between impacted and control sites. Energetic reserves were altered in mussels from the impacted sites. Glycogen content remained low at polluted sites, whatever the season. Two years after the Hebei Spirit oil spill, mussels then presented altered energetic metabolism. Further investigations are thus warranted to monitor the sustainability of mussel populations on the oil spilled West coast of Korea.

  16. Alien parasitic copepods in mussels and oysters of the Wadden Sea

    NARCIS (Netherlands)

    Elsner, N.O.; Jacobsen, S.; Thieltges, D.W.; Reise, K.

    2011-01-01

    Molluscan intestinal parasites of the genus Mytilicola, specifically M. intestinalis, were initially introduced into bivalves in the North Sea in the 1930s. It was presumably introduced from the Mediterranean with ship-fouling mussels, then attained epidemic proportions in Mytilus edulis in the 1950

  17. Poscosecha de la gulupa: (passiflora edulis sims)

    OpenAIRE

    Orjuela-Baquero, Nubia Marcela; Campos Alba, Sandra; Sánchez Nieves, Jimena; Melgarejo, Luz Marina; Hernández, María Soledad; Sierra A., César A.; Gutiérrez Carranza, Luis Alejandro; Martínez, Sugey M.; Moreno-Chacón, Leonardo; Pérez-Martínez, Laura Victoria; Flórez, Laura Marcela

    2011-01-01

    Este libro presenta resultados de investigación, generados a través del proyecto “Efecto de las condiciones poscosecha sobre la fisiología, bioquímica, conservación y análisis proteómico en frutos de gulupa “Passiflora edulis Sims” ejecutado por la Universidad Nacional de Colombia, con la colaboración de la empresa OCATI S.A, y financiación por Colciencias; con el apoyo del proyecto “Materiales poliméricos para la fabricación de un empaque apropiado para el manejo poscosecha de la Gulupa” fi...

  18. Distribution of Mytilus taxa in European coastal areas as inferred from molecular markers

    Science.gov (United States)

    Kijewski, T.; Śmietanka, B.; Zbawicka, M.; Gosling, E.; Hummel, H.; Wenne, R.

    2011-02-01

    The genetic constitution of mussels ( Mytilus spp.) was studied by means of three nuclear (Me 15/16, EF-bis, ITS) and one mtDNA (ND2-COIII) marker on a large European scale. In addition to a sharp cline between Atlantic and Mediterranean M. galloprovincialis, we observed a clear genetic distinction between the Black Sea and Mediterranean populations and a higher incidence of M. trossulus than reported so far in northern European populations. The frequency of M. galloprovincialis nuclear alleles was high along the Iberian Peninsula and decreased abruptly along the French coasts with a high frequency of M. edulis alleles in the Bay of Biscay, The Netherlands, Germany, Iceland, Barents and White Seas, and with little evidence of introgression between the two taxa. M. trossulus alleles were observed in the Baltic Sea and Danish Straits as expected. In addition, occurrence of M. trossulus alleles in cold waters of Iceland, Barents Sea and White Sea is reported for the first time.

  19. Microplastics in commercial bivalves from China.

    Science.gov (United States)

    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong

    2015-12-01

    We investigated microplastic pollution in 9 commercial bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The number of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on average 10.5 items/g and exhibited the highest levels of microplastics by weight. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33-84% of the total microplastics calculated by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in commercial bivalves from China. More intensive investigations on microplastics should be conducted in seafood.

  20. A study of model bivalve siphonal currents

    Science.gov (United States)

    Monismith, Stephen G.; Koseff, Jeffrey R.; Thompson, Janet K.; O'Riordan, Catherine A.; Nepf, Heidi M.

    1990-01-01

    We carried out experiments studying the hydrodynamics of bivalve siphonal currents in a laboratory flume. Rather than use living animals, we devised a simple, model siphon pair connected to a pump. Fluorescence-based flow visualization was used to characterize siphon-jet flows for several geometric configurations and flow speeds. These measurements show that the boundary-layer velocity profile, siphon height, siphon pair orientation, and size of siphon structure all affect the vertical distribution of the excurrent flow downstream of the siphon pair and the fraction of excurrent that is refiltered. The observed flows may effect both the clearance rate of an entire population of siphonate bivalves as well as the efficiency of feeding of any individual. Our results imply that field conditions are properly represented in laboratory flume studies of phytoplankton biomass losses to benthic bivalves when the shear velocity and bottom roughness are matched to values found in the field. Numerical models of feeding by a bivalve population should include an effective sink distribution which is created by the combined incurrent-excurrent flow field. Near-bed flows need to be accounted for to properly represent these benthic-pelagic exchanges. We also present velocity measurements made with a laser-Doppler anemometer (LDA) for a single configuration (siphons flush with bed, inlet downstream) that show that the siphonal currents have a significant local effect on the properties of a turbulent boundary layer.

  1. Bivalve grazing can shape phytoplankton communities

    Science.gov (United States)

    Lucas, Lisa; Cloern, James E.; Thompson, Janet K.; Stacey, Mark T.; Koseff, Jeffrey K.

    2016-01-01

    The ability of bivalve filter feeders to limit phytoplankton biomass in shallow waters is well-documented, but the role of bivalves in shaping phytoplankton communities is not. The coupled effect of bivalve grazing at the sediment-water interface and sinking of phytoplankton cells to that bottom filtration zone could influence the relative biomass of sinking (diatoms) and non-sinking phytoplankton. Simulations with a pseudo-2D numerical model showed that benthic filter feeding can interact with sinking to alter diatom:non-diatom ratios. Cases with the smallest proportion of diatom biomass were those with the fastest sinking speeds and strongest bivalve grazing rates. Hydrodynamics modulated the coupled sinking-grazing influence on phytoplankton communities. For example, in simulations with persistent stratification, the non-sinking forms accumulated in the surface layer away from bottom grazers while the sinking forms dropped out of the surface layer toward bottom grazers. Tidal-scale stratification also influenced vertical gradients of the two groups in opposite ways. The model was applied to Suisun Bay, a low-salinity habitat of the San Francisco Bay system that was transformed by the introduction of the exotic clam Potamocorbula amurensis. Simulation results for this Bay were similar to (but more muted than) those for generic habitats, indicating that P. amurensis grazing could have caused a disproportionate loss of diatoms after its introduction. Our model simulations suggest bivalve grazing affects both phytoplankton biomass and community composition in shallow waters. We view these results as hypotheses to be tested with experiments and more complex modeling approaches.

  2. Identification and Characterization of a Novel Family of Cysteine-Rich Peptides (MgCRP-I) from Mytilus galloprovincialis.

    Science.gov (United States)

    Gerdol, Marco; Puillandre, Nicolas; De Moro, Gianluca; Guarnaccia, Corrado; Lucafò, Marianna; Benincasa, Monica; Zlatev, Ventislav; Manfrin, Chiara; Torboli, Valentina; Giulianini, Piero Giulio; Sava, Gianni; Venier, Paola; Pallavicini, Alberto

    2015-07-21

    We report the identification of a novel gene family (named MgCRP-I) encoding short secreted cysteine-rich peptides in the Mediterranean mussel Mytilus galloprovincialis. These peptides display a highly conserved pre-pro region and a hypervariable mature peptide comprising six invariant cysteine residues arranged in three intramolecular disulfide bridges. Although their cysteine pattern is similar to cysteines-rich neurotoxic peptides of distantly related protostomes such as cone snails and arachnids, the different organization of the disulfide bridges observed in synthetic peptides and phylogenetic analyses revealed MgCRP-I as a novel protein family. Genome- and transcriptome-wide searches for orthologous sequences in other bivalve species indicated the unique presence of this gene family in Mytilus spp. Like many antimicrobial peptides and neurotoxins, MgCRP-I peptides are produced as pre-propeptides, usually have a net positive charge and likely derive from similar evolutionary mechanisms, that is, gene duplication and positive selection within the mature peptide region; however, synthetic MgCRP-I peptides did not display significant toxicity in cultured mammalian cells, insecticidal, antimicrobial, or antifungal activities. The functional role of MgCRP-I peptides in mussel physiology still remains puzzling.

  3. Immunomodulation of Mytilus hemocytes by individual estrogenic chemicals and environmentally relevant mixtures of estrogens: in vitro and in vivo studies.

    Science.gov (United States)

    Canesi, Laura; Lorusso, Lucia Cecilia; Ciacci, Caterina; Betti, Michele; Rocchi, Marco; Pojana, Giulio; Marcomini, Antonio

    2007-02-15

    Endocrine disrupting compounds (EDCs) are almost ubiquitous in the aquatic environment. In the marine bivalve Mytilus the natural estrogen 17beta-estradiol (E2) and different EDCs have been recently demonstrated to affect the function of the immune cells, the hemocytes. The effects were Tamoxifen-sensitive and were mediated by rapid modulation of kinase-mediated transduction pathways. In this work we compared the in vitro effects of individual estrogenic chemicals (E2, EE: 17alpha-ethynyl estradiol; MES: mestranol; NP: nonylphenol; NP1EC: nonylphenol monoethoxylate carboxylate; BPA: bisphenol A; BP: benzophenone) on hemocyte parameters: lysosomal membrane stability (LMS), phagocytosis, lysozyme release. LMS was the most sensitive effect parameter, showing a decreasing trend at increasing concentrations of estrogens. EC50 values obtained from LMS data were utilized to calculate the estradiol equivalency factor (EEF) for each compound; these EEFs allowed for an estimation of the estrogenic potential of a synthetic mixture with a composition very similar to that previously found in waters of the Venice lagoon. Concentrated mixtures significantly affected hemocyte parameters in vitro and the effects were prevented by Tamoxifen. Significant effects of the mixture were also observed in vivo, at longer exposure times and at concentrations comparable with environmental exposure levels. The results indicate that Mytilus immune parameters can be suitably utilized to evaluate the estrogenic potential of environmental samples.

  4. Chemical constituents of Carissa edulis Vahl

    Directory of Open Access Journals (Sweden)

    Hanan M. Al-Youssef

    2017-01-01

    Full Text Available Reinvestigation of the biologically active ethyl acetate and butanol extracts of the aerial parts of Carissa edulis afforded 3-O-acetyl chlorogenic acid (I, along with four known flavonol glucosides including, kaempferol 3-O-β-d glucopyranoside (II, quercetin-3-O-β-d glucopyranoside (III, rhamnetin-3-O-β-d glucopyranoside (IV and isorhamnetin-3-O-β-d-glucopyranoside (V from ethyl acetate fraction. Isorhamnetin-3-O-β-d-glucopyranoside-(2″→1″′-rhamnopyranoside (VI, Caredulis, 1-{1-[2-(2 hydroxypropoxy propoxy] propan-2-yloxy} propan-2-ol (VII and (+ butyl-O-α-l-rhamnoside (VIII were isolated from butanol fraction. Characterization of these compounds was achieved by various spectroscopic methods (UV, MS, 1H NMR, 13C NMR, COSY, HSQC and HMBC and through comparison with published data. Compounds I–VIII were isolated from C. edulis for the first time, while compounds VII and VIII were isolated for the first time from nature.

  5. Insights into the innate immunity of the Mediterranean mussel Mytilus galloprovincialis

    Directory of Open Access Journals (Sweden)

    Novoa Beatriz

    2011-01-01

    Full Text Available Abstract Background Sessile bivalves of the genus Mytilus are suspension feeders relatively tolerant to a wide range of environmental changes, used as sentinels in ecotoxicological investigations and marketed worldwide as seafood. Mortality events caused by infective agents and parasites apparently occur less in mussels than in other bivalves but the molecular basis of such evidence is unknown. The arrangement of Mytibase, interactive catalogue of 7,112 transcripts of M. galloprovincialis, offered us the opportunity to look for gene sequences relevant to the host defences, in particular the innate immunity related genes. Results We have explored and described the Mytibase sequence clusters and singletons having a putative role in recognition, intracellular signalling, and neutralization of potential pathogens in M. galloprovincialis. Automatically assisted searches of protein signatures and manually cured sequence analysis confirmed the molecular diversity of recognition/effector molecules such as the antimicrobial peptides and many carbohydrate binding proteins. Molecular motifs identifying complement C1q, C-type lectins and fibrinogen-like transcripts emerged as the most abundant in the Mytibase collection whereas, conversely, sequence motifs denoting the regulatory cytokine MIF and cytokine-related transcripts represent singular and unexpected findings. Using a cross-search strategy, 1,820 putatively immune-related sequences were selected to design oligonucleotide probes and define a species-specific Immunochip (DNA microarray. The Immunochip performance was tested with hemolymph RNAs from mussels injected with Vibrio splendidus at 3 and 48 hours post-treatment. A total of 143 and 262 differentially expressed genes exemplify the early and late hemocyte response of the Vibrio-challenged mussels, respectively, with AMP trends confirmed by qPCR and clear modulation of interrelated signalling pathways. Conclusions The Mytibase collection is rich

  6. New insights into the apoptotic process in mollusks: characterization of caspase genes in Mytilus galloprovincialis.

    Directory of Open Access Journals (Sweden)

    Alejandro Romero

    Full Text Available Apoptosis is an essential biological process in the development and maintenance of immune system homeostasis. Caspase proteins constitute the core of the apoptotic machinery and can be categorized as either initiators or effectors of apoptosis. Although the genes encoding caspase proteins have been described in vertebrates and in almost all invertebrate phyla, there are few reports describing the initiator and executioner caspases or the modulation of their expression by different stimuli in different apoptotic pathways in bivalves. In the present work, we characterized two initiator and four executioner caspases in the mussel Mytilus galloprovincialis. Both initiators and executioners showed structural features that make them different from other caspase proteins already described. Evaluation of the genes' tissue expression patterns revealed extremely high expression levels within the gland and gills, where the apoptotic process is highly active due to the clearance of damaged cells. Hemocytes also showed high expression values, probably due to of the role of apoptosis in the defense against pathogens. To understand the mechanisms of caspase gene regulation, hemocytes were treated with UV-light, environmental pollutants and pathogen-associated molecular patterns (PAMPs and apoptosis was evaluated by microscopy, flow cytometry and qPCR techniques. Our results suggest that the apoptotic process could be tightly regulated in bivalve mollusks by overexpression/suppression of caspase genes; additionally, there is evidence of caspase-specific responses to pathogens and pollutants. The apoptotic process in mollusks has a similar complexity to that of vertebrates, but presents unique features that may be related to recurrent exposure to environmental changes, pollutants and pathogens imposed by their sedentary nature.

  7. KERAGAMAN KARAKTER MORFOLOGI PLASMA NUTFAH GANYONG (CANNA EDULIS KERR.)

    OpenAIRE

    TINTIN SUHARTINI; HADIATMI -

    2012-01-01

    Morphological Characters Diversity of Canna (Canna edulis kerr.) Germplasm. Edible canna (Canna edulis) is the source of potentially of foodstuf. Edible canna have high carbohydrate and nutritions. The starch of edible canna could be exploited as a food materials and industry. Evaluation and characterization were needed to get informations good characters of edible canna for genetic variability to get improved edible canna varieties. Indonesian Center of Agricultural Biotechnology and Genetic...

  8. Oxidative stress and bivalves: a proteomic approach

    OpenAIRE

    2008-01-01

    Bivalves are of major importance in aquatic ecology, aquaculture, are widely used as sentinel species in environmental toxicology and show remarkable plasticity to molecular oxygen. Excess reactive oxygen species (ROS) arising from molecular oxygen can cause oxidative stress and this is also a consequence of exposure to many common environmental pollutants. Indices of oxidative stress have therefore found favor as biomarkers of exposure and effect in environmental toxicology. However, there i...

  9. Interactions of cationic polystyrene nanoparticles with marine bivalve hemocytes in a physiological environment: Role of soluble hemolymph proteins.

    Science.gov (United States)

    Canesi, Laura; Ciacci, Caterina; Fabbri, Rita; Balbi, Teresa; Salis, Annalisa; Damonte, Gianluca; Cortese, Katia; Caratto, Valentina; Monopoli, Marco P; Dawson, Kenneth; Bergami, Elisa; Corsi, Ilaria

    2016-10-01

    The bivalve Mytilus galloprovincialis has proven as a suitable model invertebrate for evaluating the potential impact of nanoparticles (NPs) in the marine environment. In particular, in mussels, the immune system represents a sensitive target for different types of NPs. In environmental conditions, both NP intrinsic properties and those of the receiving medium will affect particle behavior and consequent bioavailability/uptake/toxicity. However, the evaluation of the biological effects of NPs requires additional understanding of how, once within the organism, NPs interact at the molecular level with cells in a physiological environment. In mammalian systems, different NPs associate with serum soluble components, organized into a "protein corona", which affects particle interactions with target cells. However, no information is available so far on the interactions of NPs with biological fluids of aquatic organisms. In this work, the influence of hemolymph serum (HS) on the in vitro effects of amino modified polystyrene NPs (PS-NH2) on Mytilus hemocytes was investigated. Hemocytes were incubated with PS-NH2 suspensions in HS (1, 5 and 50µg/mL) and the results were compared with those obtained in ASW medium. Cell functional parameters (lysosomal membrane stability, oxyradical production, phagocytosis) were evaluated, and morphological changes were investigated by TEM. The activation state of the signalling components involved in Mytilus immune response (p38 MAPK and PKC) was determined. The results show that in the presence of HS, PS-NH2 increased cellular damage and ROS production with respect to ASW medium. The effects were apparently mediated by disregulation of p38 MAPK signalling. The formation of a PS-NH2-protein corona in HS was investigated by centrifugation, and 1D- gel electrophoresis and nano-HPLC-ESI-MS/MS. The results identified the Putative C1q domain containing protein (MgC1q6) as the only component of the PS-NH2 hard protein corona in Mytilus

  10. Uptake and retention of metallic nanoparticles in the Mediterranean mussel (Mytilus galloprovincialis)

    Energy Technology Data Exchange (ETDEWEB)

    Hull, Matthew S.; Vikesland, Peter J. [Virginia Tech Department of Civil and Environmental Engineering, Blacksburg, VA (United States); Virginia Tech Institute for Critical Technology and Applied Science (ICTAS) (United States); Virginia Tech Center for Sustainable Nanotechnology (VT SuN) (United States); Center for the Environmental Implications of Nanotechnology (CEINT) (United States); Schultz, Irvin R., E-mail: ir_schultz@pnl.gov [Battelle Pacific Northwest National Laboratory (PNNL), Marine Sciences Laboratory, Sequim, WA (United States)

    2013-09-15

    Highlights: •We measured uptake of two types of nanomaterials in a marine mussel. •Uptake from water was rapid and complete in less than 24 h. •Only particles suspended in the water appeared to be absorbed. •Most absorbed nanomaterial was concentrated in the digestive gland. -- Abstract: We measured the uptake, distribution and elimination of two types of metallic nanoparticles (MetNPs) by the aquatic mussel Mytilus galloprovincialis in static seawater column exposures. Test MetNPs included polyethylene glycol (PEG) functionalized Fe{sub 3}O{sub 4} nanoparticles (PEG-FeOxNP) and PEG-functionalized cadmium-selenide quantum dots (PEG-Qdot). Exposure water was sampled at various times to assess MetNP clearance, and mussels were serially euthanized to assess uptake of MetNPs into the hemolymph, digestive gland, and remaining carcass. Results indicated that >90% of both types of MetNPs were taken up by mussels within 8 h of initial exposure. Nearly the entire retained dose of FeOxNPs and PEG-Qdots was deposited in the digestive gland. Our results provide important insights on the uptake and elimination kinetics of MetNPs in filter-feeding marine bivalves, and will be useful for subsequent development of toxicokinetic models to predict the kinetics of these processes.

  11. Toxicokinetics and tissue distribution of cadmium-based Quantum Dots in the marine mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Rocha, Thiago Lopes; Gomes, Tânia; Pinheiro, José Paulo; Sousa, Vânia Serrão; Nunes, Luís Miguel; Teixeira, Margarida Ribau; Bebianno, Maria João

    2015-09-01

    Environmental health hazards of Quantum Dots (QDs) are of emergent concern, but limited data is available about their toxicokinetics (TK) and tissue distribution in marine bivalves. This study investigated the QDs behavior in seawater, their TK and tissue distribution in Mytilus galloprovincialis, in comparison with soluble Cd. Mussels were exposed to CdTe QDs and soluble Cd for 21 days at 10 μgCd L(-1) followed by a 50 days depuration. TK of QDs in mussels is related to the homo-aggregate uptake, surface charge, aggregation and precipitation as key factors. There were tissue- and time-dependent differences in the TK of both Cd forms, and soluble Cd is the most bioavailable form. Digestive gland is a preferential site for QDs storage and both Cd forms are not eliminated by mussels (t1/2>50 days). Results indicate that the TK model of CdTe QDs in marine mussels is distinct from their soluble counterparts.

  12. The myostatin gene of Mytilus chilensis evidences a high level of polymorphism and ubiquitous transcript expression.

    Science.gov (United States)

    Núñez-Acuña, Gustavo; Gallardo-Escárate, Cristian

    2014-02-15

    Myostatin (MSTN) is a protein of the Transforming Growth Factor-β (TGF-β) superfamily and plays a crucial role in muscular development for higher vertebrates. However, its biological function in marine invertebrates remains undiscovered. This study characterizes the full-length sequence of the Mytilus chilensis myostatin gene (Mc-MSTN). Furthermore, tissue transcription patterns and putative single nucleotide polymorphisms (SNPs) were also identified. The Mc-MSTN cDNA sequence showed 3528 base pairs (bp), consisting of 161 bp of 5' UTR, 2,110 bp of 3' UTR, and an open reading frame of 1,257 bp encoding for 418 amino acids and with an RXXR proteolytic site and nine cysteine-conserved residues. Gene transcription analysis revealed that the Mc-MSTN has ubiquitous expression among several tissues, with higher expression in the gonads and mantle than in the digestive gland, gills, and hemolymph. Furthermore, high levels of polymorphisms were detected (28 SNPs in 3'-UTR and 9 SNPs in the coding region). Two SNPs were non-synonymous and involved amino acid changes between Glu/Asp and Thr/Ile. Until now, the MSTN gene has been mainly related to muscle growth in marine bivalves. However, the present study suggests a putative biological function not entirely associated to muscle tissue and contributes molecular evidence to the current debate about the function of the MSTN gene in marine invertebrates.

  13. Tissue distribution of neutral deoxyribonuclease (DNase) activity in the mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Bihari, Nevenka; Fafandel, Maja; Perić, Lorena

    2007-07-01

    The presence of neutral DNase activity in bivalves is reported for the first time. The enzyme activity in four tissues of the mussel Mytilus galloprovincialis was analyzed by three different methods (i) specific denaturating SDS-PAGE zymogram, (ii) sensitive single radial enzyme diffusion (SRED) assay and (iii) rapid and sensitive fluorimetric determination of DNase activity with PicoGreen. The fluorimetric assay was rapid and sensitive enough for determination of hydrolytic activity of dsDNA in mussel hepatopancreas, adductor, gills and mantle. Maximal activity in all mussel tissue extracts was obtained in the presence of Ca(2+) and Mg(2+) at pH 7.0 with dsDNA as substrate. The neutral DNase activity in mussel tissue decreases in order hepatopancreas, mantle>gills>adductor. The enzyme activity displays interindividual variability in particular tissue as well as variability among tissues within one specimen. In the hepatopancreas one to three distinct proteins expressing neutral, Ca(2+), Mg(2+)-dependent, DNase activity were detected by denaturating SDS-PAGE zymogram. This heterogeneity of neutral nucleases involved in DNA hydrolysis in hepatopancreas could reflect interindividual variability in mussel food utilization and nutrient requirement.

  14. Ciclo gonadal del chorito Mytilus chilensis (Bivalvia: Mytilidae en dos localidades del sur de Chile Gonadal cycle of the mussel Mytilus chilensis (Bivalvia: Mytilidae at two localities in southern of Chile

    Directory of Open Access Journals (Sweden)

    Pablo A Oyarzún

    2011-11-01

    Full Text Available Se analizó de forma cualitativa y cuantitativa el ciclo gonadal del bivalvo Mytilus chilensis en las localidades de Chaihuín y bahía Yal, sur de Chile, entre octubre 2007 y junio 2008. Por medio de análisis histológico gonadal se determinaron cuatro estadios gametogénicos y a su vez se estimó en forma cuantitativa, el Volumen de la Fracción Gamética (VFG, el porcentaje de tejido interfolicular y el índice gonadal. El análisis cuantitativo (VFG fue el mejor indicador para determinar los desoves. En los ejemplares de Chaihuín se observaron dos eventos de emisión gamética en forma simultánea en ambos sexos, que ocurrieron en octubre y marzo. Sin embargo, en los ejemplares de bahía Yal se registraron cuatro desoves, principalmente de marzo a junio (otoño, cuando la temperatura del agua disminuyó. Se determinó una escasa relación entre el Índice Gonadosomático (IG y los estadios gametogénicos, al igual que entre el IG y el porcentaje de ovocitos maduros, por ende el IG no sería un indicador apropiado para los desoves en esta especie. Se sugiere la revisión del periodo de veda de Mytilus chilensis (1 noviembre a 31 diciembre, ya que la mayor parte de los individuos de las poblaciones estudiadas, maduran principalmente en octubre. En ambas localidades, el porcentaje de tejido conjuntivo de los especímenes estudiados fluctúo entre 15 y 70% de cobertura gonadal. Los resultados obtenidos mostraron diferencias en los ciclos reproductivos de Mytilus chilensis entre las localidades analizadas, las que se podrían atribuir a diferencias ambientales (e.g. temperatura causadas por el gradiente latitudinal.A qualitative and quantitative analysis was carried out of the gonadal cycle of the bivalve Mytilus chilensis from Chaihuín and Yal bay, southern Chile, between October 2007 and June 2008. Four gametogenic stages were determined using histological analysis of the gonads, and quantitative estimates were made of the Gametic Volume

  15. Active pelagic migrations of the bivalve Macoma balthica are dangerous

    NARCIS (Netherlands)

    Hiddink, J.G.; Kock, R.P; Wolff, W.J.

    2002-01-01

    The bivalve Macoma balthica migrates twice during the benthic part of its life cycle. During the spring migration (May-June), the newly settled spat (0-group) migrates to the nurseries in the high intertidal. Seven to nine months later, the bivalves migrate back to the low tidal flats and the subtid

  16. The role of the starfish (Asterias rubens L.) predation in blue mussel (Mytilus edulis L.) seedbed stability

    NARCIS (Netherlands)

    Agüera García, A.

    2015-01-01

    Abstract Mussel beds are an important ecological component in the Wadden Sea. Mussels’ offspring settle massively in new suitable areas, forming seedbeds that may disappear again within months. The probability of a seedbed to survive the first winter is defined as seedbed sta

  17. Effects of tidal zonation on size and genetic traits of Mytilus edulis (L.) and Macoma balthica (L.)

    NARCIS (Netherlands)

    Hummel, H.; Bijok, P.; Bogaards, R.H.

    1996-01-01

    Genetic and some ecophysiological traits of mussels collected in the European Arctic, up to their northeastern distribution limit in the Barents Sea, were studied and compared with traits of mussels from the Mediterranean, Atlantic and Baltic. The genetic traits of these populations we-re analysed b

  18. Changes in benthos associated with mussel (Mytilus edulis L.) farms on the west-coast of Scotland.

    Science.gov (United States)

    Wilding, Thomas A; Nickell, Thomas D

    2013-01-01

    Aquaculture, as a means of food production, is growing rapidly in response to an increasing demand for protein and the over-exploitation of wild fisheries. This expansion includes mussels (family Mytilidae) where production currently stands at 1.5 million tonnes per annum. Mussel culture is frequently perceived as having little environmental impact yet mussel biodeposits and shell debris accumulate around the production site and are linked to changes in the benthos. To assess the extent and nature of changes in benthos associated with mussel farming grab and video sampling around seven mussel farms was conducted. Grab samples were analysed for macrofauna and shell-hash content whilst starfish were counted and the shell-hash cover estimated from video imaging. Shell-hash was patchily distributed and occasionally dominated sediments (maximum of 2116 g per 0.1 m(2) grab). Mean shell-hash content decreased rapidly at distances >5 m from the line and, over the distance 1-64 m, decreased by three orders of magnitude. The presence of shell-hash and the distance-from-line influenced macrofaunal assemblages but this effect differed between sites. There was no evidence that mussel farming was associated with changes in macrobenthic diversity, species count or feeding strategy. However, total macrofaunal count was estimated to be 2.5 times higher in close proximity to the lines, compared with 64 m distance, and there was evidence that this effect was conditional on the presence of shell-hash. Starfish density varied considerably between sites but, overall, they were approximately 10 times as abundant close to the mussel-lines compared with 64 m distance. There was no evidence that starfish were more abundant in the presence of shell-hash visible on the sediment surface. In terms of farm-scale benthic impacts these data suggest that mussel farming is a relatively benign way of producing food, compared with intensive fish-farming, in similar environments.

  19. Interactions between the introduced Pacific oyster Crassostrea gigas and the indigenous blue mussel Mytilus edulis. Local-scale food competition

    NARCIS (Netherlands)

    Hans, I.W.

    2004-01-01

    The aim of this study was to determine if food competition between mussels and oysters occurs, and how mussel and oyster growth is affected by this interaction. This was done by relating mussel growth to oyster density relating oyster growth to oyster biomass and perform a field control, by inventor

  20. Bioenergetic model predictions of actual growth and allometric transitions during ontogeny of juvenile blue mussels Mytilus edulis

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Lundgreen, Kim; Riisgård, Hans Ulrik

    2013-01-01

    with predictions based on a previously developed bioenergetic growth model (BEG) for W> 10 mg (μ =aWb, a = 0.871× C – 0.986; b = –0.34, with μ in % d−1 and W in g) which explicitly takes into account the prevailing chla concentration C (μg L−1). Results for W...Wb), now with exponent b = −0.13 close to the suggested value (b ≈ −0.1) from experimentally established correlations for filtration and respiration rate of post-metamorphic mussels. Using the stated W(L)-relation for L> 10 mm the growth model has been expressed in terms of shell length specific growth...

  1. Pelagic and benthic nutrient regeneration processes in mussel cultures (Mytilus edulis) in a eutrophic coastal area (Skive Fjord, Denmark)

    DEFF Research Database (Denmark)

    Holmer, Marianne; Thorsen, Sandra Walløe; Carlsson, Marita Sundstein

    2015-01-01

    Long-line mussel farming has been proposed as a mitigation tool in eutrophic coastal areas as nutrients are removed from the ecosystem upon harvest of the crops and transferred back to land. Further mussels filter the water and thereby increase water transparency and promote benthic plant growth...... of this study was to explore the environmental interactions of a long-line mussel farm located in a eutrophic coastal area (Skive Fjord, Denmark) by studying the nutrient cycling in the water column and sediments and assessing their contribution to the nutrient dynamics and oxygen conditions in the fjord....... The mussel lines contributed with nutrients, primarily ammonium, to the pool of nutrients in the water column and the contribution increased as the biomass of mussels in the farm increased. The sedimentation of biodeposits was only slightly higher at the farm (51–86 %) compared with a reference site...

  2. Reducing the impact of blue mussel (Mytilus edulis) dredging on the ecosystem in shallow water soft bottom areas

    DEFF Research Database (Denmark)

    Frandsen, Rikke; Eigaard, Ole Ritzau; Poulsen, Louise K.

    2015-01-01

    performance of the two gears by fishing in areas with a known blue mussel density. Results from the twin haul experiment demonstrate that the weight of sediment retained in the gear per square metre fished is 49% less in the light dredge compared with the Dutch dredge which will reduce resuspension...... reduce the impact of the fishery on the ecosystem by (i) reducing resuspension of sediment, (ii) reducing fuel consumption, and (iii) potentially reducing energy transfer to the sediment through a reduced gear drag resistance. A potential increase in catch efficiency may reduce the area affected. Fishing...

  3. Bioenergetic model predictions of actual growth and allometric transitions during ontogeny of juvenile blue mussels Mytilus edulis

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Lundgreen, Kim; Riisgård, Hans Ulrik

    2013-01-01

    The growth rates of blue mussels Mytilusedulis on ropes in the Great Belt (Denmark) have been studied during the growth season of one year, from settling to about 30 mm shell length mussels, covering >4 decades of body mass. Measured shell length (L, mm) and dry weight of soft parts (W, μg) for L...... > 10 mm followed a power-law (W = 2.15L3.40) which supplemented an existing power-law for L ... with predictions based on a previously developed bioenergetic growth model (BEG) for W> 10 mg (μ =aWb, a = 0.871× C – 0.986; b = –0.34, with μ in % d−1 and W in g) which explicitly takes into account the prevailing chla concentration C (μg L−1). Results for Wlaw (μ =a...

  4. Changes in benthos associated with mussel (Mytilus edulis L. farms on the west-coast of Scotland.

    Directory of Open Access Journals (Sweden)

    Thomas A Wilding

    Full Text Available Aquaculture, as a means of food production, is growing rapidly in response to an increasing demand for protein and the over-exploitation of wild fisheries. This expansion includes mussels (family Mytilidae where production currently stands at 1.5 million tonnes per annum. Mussel culture is frequently perceived as having little environmental impact yet mussel biodeposits and shell debris accumulate around the production site and are linked to changes in the benthos. To assess the extent and nature of changes in benthos associated with mussel farming grab and video sampling around seven mussel farms was conducted. Grab samples were analysed for macrofauna and shell-hash content whilst starfish were counted and the shell-hash cover estimated from video imaging. Shell-hash was patchily distributed and occasionally dominated sediments (maximum of 2116 g per 0.1 m(2 grab. Mean shell-hash content decreased rapidly at distances >5 m from the line and, over the distance 1-64 m, decreased by three orders of magnitude. The presence of shell-hash and the distance-from-line influenced macrofaunal assemblages but this effect differed between sites. There was no evidence that mussel farming was associated with changes in macrobenthic diversity, species count or feeding strategy. However, total macrofaunal count was estimated to be 2.5 times higher in close proximity to the lines, compared with 64 m distance, and there was evidence that this effect was conditional on the presence of shell-hash. Starfish density varied considerably between sites but, overall, they were approximately 10 times as abundant close to the mussel-lines compared with 64 m distance. There was no evidence that starfish were more abundant in the presence of shell-hash visible on the sediment surface. In terms of farm-scale benthic impacts these data suggest that mussel farming is a relatively benign way of producing food, compared with intensive fish-farming, in similar environments.

  5. Morfoanatomia de folhas e caules de Passiflora edulis Sims, Passifloraceae Leaf and stem morphoanatomy of Passiflora edulis Sims, Passifloraceae

    Directory of Open Access Journals (Sweden)

    Josseara Beraldo

    2010-05-01

    Full Text Available Passiflora edulis Sims, espécie vegetal empregada na medicina popular e amplamente cultivada no território nacional, tem suas folhas e seus caules, muitas vezes utilizados como adulterante de amostras comerciais da droga vegetal oficializada no país também conhecida como maracujá, Passiflora alata Curtis. Caracteres morfoanatômicos de folhas e de caules de P. edulis, foram descritos e documentados. Dentre os caracteres auxiliares na distinção entre a droga oficial e os órgãos aéreos de P. edulis podem-se destacar o contorno da lâmina foliar, a forma da nervura mediana em secção transversal, o número e a localização de nectários extraflorais e, o indumentoPassiflora edulis Sims, vegetal species employed in the Brazilian traditional medicine and broadly cultivated across its territory, has its leaves and stems often used as an adulterant for commercial samples of the crude drug Passiflora alata Curtis, officially known in Brazil as "maracujá". Morphoanatomic data from leaves and stems in P. edulis were described and documented. Amongst these characteristics, the shape of the foliar blade, the shape of the midrib in transverse section, the number and the location of the extrafloral nectaries and the indumentum are all emphasized.

  6. Cambrian bivalved arthropod reveals origin of arthrodization.

    Science.gov (United States)

    Legg, David A; Sutton, Mark D; Edgecombe, Gregory D; Caron, Jean-Bernard

    2012-12-07

    Extant arthropods are diverse and ubiquitous, forming a major constituent of most modern ecosystems. Evidence from early Palaeozoic Konservat Lagerstätten indicates that this has been the case since the Cambrian. Despite this, the details of arthropod origins remain obscure, although most hypotheses regard the first arthropods as benthic predators or scavengers such as the fuxianhuiids or megacheirans ('great-appendage' arthropods). Here, we describe a new arthropod from the Tulip Beds locality of the Burgess Shale Formation (Cambrian, series 3, stage 5) that possesses a weakly sclerotized thorax with filamentous appendages, encased in a bivalved carapace, and a strongly sclerotized, elongate abdomen and telson. A cladistic analysis resolved this taxon as the basal-most member of a paraphyletic grade of nekto-benthic forms with bivalved carapaces. This grade occurs at the base of Arthropoda (panarthropods with arthropodized trunk limbs) and suggests that arthrodization (sclerotization and jointing of the exoskeleton) evolved to facilitate swimming. Predatory and fully benthic habits evolved later in the euarthropod stem-lineage and are plesiomorphically retained in pycnogonids (sea spiders) and euchelicerates (horseshoe crabs and arachnids).

  7. Nutritional strategies of the hydrothermal ecosystem bivalves

    Science.gov (United States)

    Le Pennec, Marcel; Donval, Anne; Herry, Angèle

    Studies of deep-sea hydrothermal bivalves have revealed that the species, which are strictly dependent upon the interstitial fluid emissions, derive their food indirectly via symbiotic relationships with chemosynthetic bacteria present in their gill tissues. As the gill plays the main trophic role, structural and ultrastructural modifications occur in the digestive tract. Scanning and transmission electron microscope studies reveal that the digestive system of species belonging to the genera Calyptogena, Bathymodiolus and Bathypecten have anatomical differences. In Calyptogena, the reduction of several parts of the digestive tract and the stomach content which is either empty or full, according to the various species examined indicate that the digestive system is hardly if at all functional. In Bathymodiolus, the labial palps are well developed, the stomach is always full with particles and the two cellular types, digestive and secretory, are present in the digestive gland. All these characteristics indicate that the digestive system is functional. In Bathypecten, the digestive tract is well developed and it seems that it plays the main trophic role. We conclude that the nutritional strategies of the hydrothermal vents bivalves are quite varied. They range from a normal trophic process, through a mixotrophic diet, to one based purely on chemoautotrophic bacteria. The strategy of each species is adapted to and influences its distribution.

  8. Validation of the flow-through chamber (FTC) and steady-state (SS) methods for clearance rate measurements in bivalves

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgård, Hans Ulrik

    2012-01-01

    of particles cleared is in itself neither a criterion for valid CR measurement, nor an indicator of appropriate ‘chamber geometry’ as hitherto adapted in many studies. For the ‘steady-state method’ (SS), the design must ensure that inflow water becomes fully mixed with the bivalve’s excurrent flow to establish...... measurements depends on the percent reduction in particle concentration (1006P) from inlet to outlet of the ideal ‘chamber geomety’. For FTC, it decreases with increasing values of P while for SS it first decreases but then increases again, suggesting the use of an intermediate value of P. In practice......, the optimal value of P may depend on the given ‘chamber geometry’. The fundamental differences between the FTC and the SS methods and practical guidelines for their use are pointed out, and new data on CR for the blue mussel, Mytilus edulis, illustrate a design and use of the SS method which may be employed...

  9. Hypoxia-Inducible Factor α and Hif-prolyl Hydroxylase Characterization and Gene Expression in Short-Time Air-Exposed Mytilus galloprovincialis.

    Science.gov (United States)

    Giannetto, Alessia; Maisano, Maria; Cappello, Tiziana; Oliva, Sabrina; Parrino, Vincenzo; Natalotto, Antonino; De Marco, Giuseppe; Barberi, Chiara; Romeo, Orazio; Mauceri, Angela; Fasulo, Salvatore

    2015-12-01

    Aquatic organisms experience environmental hypoxia as a result of eutrophication and naturally occurring tidal cycles. Mytilus galloprovincialis, being an anoxic/hypoxic-tolerant bivalve, provides an excellent model to investigate the molecular mechanisms regulating oxygen sensing. Across the animal kingdom, inadequacy in oxygen supply is signalled predominantly by hypoxia-inducible factors (HIF) and Hif-prolyl hydroxylases (PHD). In this study, hif-α 5'-end and partial phd mRNA sequences from M. galloprovincialis were obtained. Phylogenetic and molecular characterization of both HIF-α and PHD putative proteins showed shared key features with the respective orthologues from animals strongly suggesting their crucial involvement in the highly conserved oxygen sensing pathway. Both transcripts displayed a tissue-specific distribution with prominent expression in gills. Quantitative gene expression analysis of hif-α and phd mRNAs from gills of M. galloprovincialis demonstrated that both these key sensors are transcriptionally modulated by oxygen availability during the short-time air exposure and subsequent re-oxygenation treatments proving that they are critical players of oxygen-sensing mechanisms in mussels. Remarkably, hif-α gene expression showed a prompt and transient response suggesting the precocious implication of this transcription factor in the early phase of the adaptive response to hypoxia in Mytilus. HIF-α and PHD proteins were modulated in a time-dependent manner with trends comparable to mRNA expression patterns, thus suggesting a central role of their transcriptional regulation in the hypoxia tolerance strategies in marine bivalves. These results provide molecular information about the effects of oxygen deficiency and identify hypoxia-responsive biomarker genes in mussels applicable in ecotoxicological studies of natural marine areas.

  10. Allometry of a neotropical palm, Euterpe edulis Mart. Alometria de uma palmeira Neotropical, Euterpe edulis Mart

    Directory of Open Access Journals (Sweden)

    Luciana F. Alves

    2004-06-01

    Full Text Available The stem allometry (stem diameter vs. tree height of a Neotropical palm (Euterpe edulis found in rain and seasonal forest of Southeastern Brazil was examined. Observed height-diameter relationships along the stem (diameter at ground level, (dgl, and diameter at breast height (dbh were compared to three theoretical stability mechanical models: elastic similarity, stress similarity and geometric similarity. Slopes of log-transformed height-diameter relationships did not lie near those predicted by any stability mechanical models. Significant differences in stem allometry were found when comparing dgl to dbh, suggesting greater increase in dbh with height. The relationship between stability safety factor (SSF and palm height showed that both dgl and dbh were found to be above McMahon's theoretical buckling limit for dicotyledonous trees, but some individuals approached this limit in relation to dbh. Despite displaying a similar decreasing pattern of SSF with height, differences found in SSF along the stem - greater SSF for dgl when compared to dbh - indicate that the risk of mechanism failure in palms depends upon the size and varies along the stem. Distinct allometric relationships along the stem obtained for Euterpe edulis may be reflecting possible differences in stem design and growth strategies.Neste trabalho foram analisadas as relações entre o diâmetro e a altura de uma palmeira Neotropical (Euterpe edulis comum na Floresta Atlântica do SE do Brasil. As relações observadas entre a altura e o diâmetro ao longo do estipe (diâmetro ao nível do solo (DAS, e diâmetro ao nível do peito (DAP foram comparadas a três modelos teóricos de estabilidade mecânica: similaridade elástica, similaridade de estresse e similaridade geométrica. As inclinações das regressões altura-diâmetro não se ajustaram a nenhum dos modelos de estabilidade mecânica. Diferenças significativas na alometria do estipe foram encontradas comparando-se as rela

  11. Dynamics of sheet nacre formation in bivalves.

    Science.gov (United States)

    Rousseau, Marthe; Meibom, Anders; Gèze, Marc; Bourrat, Xavier; Angellier, Martine; Lopez, Evelyne

    2009-03-01

    Formation of nacre (mother-of-pearl) is a biomineralization process of fundamental scientific as well as industrial importance. However, the dynamics of the formation process is still not understood. Here, we use scanning electron microscopy and high spatial resolution ion microprobe depth-profiling to image the full three-dimensional distribution of organic materials around individual tablets in the top-most layer of forming nacre in bivalves. Nacre formation proceeds by lateral, symmetric growth of individual tablets mediated by a growth-ring rich in organics, in which aragonite crystallizes from amorphous precursors. The pivotal role in nacre formation played by the growth-ring structure documented in this study adds further complexity to a highly dynamical biomineralization process.

  12. Evidence for variable crystallinity in bivalve shells

    Science.gov (United States)

    Jacob, D. E.; Wehrmeister, U.

    2012-04-01

    Bivalve shells are used as important palaeoclimate proxy archives and monitor regional climate variations. The shells mostly exist of two crystalline polymorphic phases of calcium carbonate calcite (rombohedric) and aragonite (orthorhombic). Calcite is the most stable polymorph at standard conditions, whereas vaterite (hexagonal) is the least stable and only rarely found in these structures. Shells are characterized by organized structures and several micro architectures of mollusc shell structures have been identified: Nacre shows different types: columnar and bricked forms and consists of composite inorganic- organic at the nano-scale. They are well known to display a "brick and mortar" structure. By AFM and FIB/TEM methods it could be shown, that its nanostructure consists of the structures in the range of 50 - 100 nm [1, 2]. These structures are vesicles, consisting of CaCO3 and are individually coated by a membrane. Most probably, the mantle epithelian cells of the bivalve extrude CaCO3 vesicles. By Raman spectroscopic investigations the crystalline CaCO3 polymorphs calcite, aragonite and vaterite, as well as ACC were determined. For some species (Diplodon chilensis patagonicus, Hyriopsis cumingii) pure ACC (i.e. not intermingled with a crystalline phase) could be identified. The presence of an amorphous phase is generally deduced from the lack of definite lattice modes, whereas a broad Raman band in this region is to observe. In most of the cultured pearls (Pinctada maxima and genus Hyriopsis) the ν1-Raman band of ACC clearly displays an asymmetric shape and splits into two different bands according to a nanocrystalline and an amorphous fraction. The FWHMs of most of the crystalline fractions are too high for well crystallized materials and support the assumption of nanocrystalline calcium carbonate polymorph clusters in ACC. They are primarily composed of amorphous calcium carbonate (ACC) which is later transformed into a crystalline modification [3

  13. Initial development of passion fruit trees (Passiflora edulis f. flavicarpa, P. edulis f. edulis and P. alata grafted onto Passiflora cincinnata

    Directory of Open Access Journals (Sweden)

    Valdir Zucareli

    2014-10-01

    Full Text Available The present work aimed to evaluate the initial growth and leaf mineral levels in passion fruit trees (Passiflora edulis f. flavicarpa Deg., P. edulis f. edulis Sims. and P. alata Dryander grafted onto Passiflora cincinnata. To obtain seedlings, seeds were sown in plastic bags (500 mL and hypocotyl grafting was performed when seedlings reached the stage of two fully expanded leaves. Fifteen days after grafting, plants were transplanted to 10L pots filled with previously limed and fertilized soil. Each pot contained two plants and corresponded to one plot. For each commercial species studied as rootstock, experimental design was completely randomized, in 3x5 (plant type x time of harvest factorial arrangement, with four replicates of two plants per plot and five destructive harvests. Plant types were ungrafted P. cincinnata, ungrafted commercial passion fruit tree and commercial passion fruit tree grafted onto P. cincinnata. The first harvest was performed at 15 days after transplanting and the remaining ones at 14-day intervals (60, 74, 88, 102 and 116 DAS. At each harvest, the number of leaves per plant was counted, and leaf area, stem length, and stem, root, leaf and total dry matter were estimated. At the last harvest, the mineral composition (macro and micronutrients of plants was analyzed. In general, it was observed that grafting onto P. cincinnata did not interfere negatively with the initial development and mineral levels of commercial passion fruit trees, and this interference varied according to the used canopy.

  14. Characterization of pathogenic vibrios isolated from bivalve hatcheries in Galicia, NW Atlantic coast of Spain. Description of Vibrio tubiashii subsp. europaeus [corrected] subsp. nov.

    Science.gov (United States)

    Prado, Susana; Dubert, Javier; Barja, Juan L

    2015-02-01

    The taxonomic position of the bivalve pathogen PP-638 was studied together with five similar isolates. The strains were isolated from flat oyster (Ostrea edulis) and Manila clam (Venerupis philippinarum) cultures during outbreaks of disease in two shellfish hatcheries (Galicia, NW Spain). The pathogenicity, previously established for PP-638, was demonstrated with all isolates and for several bivalve species, including the original hosts. On the basis of phenotypic characterization and 16S rRNA gene sequences, a tight group was defined within the genus Vibrio. Multilocus sequence analysis (MLSA) based on concatenated sequences of the 16S rRNA gene and the five housekeeping genes recA, rpoA, pyrH, gyrB and ftsZ revealed that these strains form a cluster within the Orientalis clade, close to the species Vibrio tubiashii. The results of MLSA, the DDH rate and the phenotypic differences with the type strain of V. tubiashii supported the differentiation of the Galician isolates as a new subspecies within V. tubiashii, for which the name V. tubiashii subsp. europaeus [corrected] subsp. nov. is proposed (type strain PP-638(T)=CECT 8136(T)=DSM 7349(T)) The emended description of V. tubiashii is included. The pathogenicity assays widen the host range of V. tubiashii to add two unreported species, Venerupis decussata and Donax trunculus, and the described as relatively resistant species V. philippinarum.

  15. Biodeposition of suspended particles in fresh seawater for industrial aquaculture by filter-feeding bivalves%贝类对海水养殖新源水悬浮物的生物沉积作用

    Institute of Scientific and Technical Information of China (English)

    张延青; 张少军; 周毅; 刘鹰; 徐洋

    2011-01-01

    It is so slow to remove these materials though gravity sedimentation; and other methods will consume large energy as general mechanical filter or foam separation. In this study, In order to remove the suspended particles in fresh seawater for industrial seawater aquaculture. We chose two kinds of filter-feeding bivalves, the Pacific oyster Crassostrea gigas and the blue mussel Mytilus galloprovincialis for biodeposition of suspended particles. The biological deposition rate(BDR) by spot experiments in different times was calculated, and the efficiency of removing the suspended particles in reservoir with fresh seawater by these two kinds of bivalves was assessed. The results showed that when the temperature of reservoir was at 17-25℃, bio-deposition rates of the two kinds of filter-feeding bivalves were 1.08-1.32 g/(ind-d) (Crassostrea gigas) and 0.65~0.85 g/(ind-d) (Mytilus galloprovincialis), respectively. Compared with no bivalves in reservoir, the bio-deposition rates with cultivation of a large number of bivalves in the reservoir was higher than no bivalves. The study shows that filter-feeding bivalve could remove suspended particles in fresh seawater and reduce the treatment load of fresh seawater.%为了去除工厂化海水养殖新源水中含有的大量悬浮颗粒物,针对蓄水池中悬浮物重力沉降速率较慢,利用一般的机械过滤或泡沫分离又消耗大量能源的缺点,该试验选择适应能力强的滤食性双壳贝类太平洋牡蛎(Crassostrea gigas)和紫贻贝(Mytilus galloprovincialis),在不同时期进行现场试验,测定其对蓄水池新源水中悬浮物的生物沉积速率并评估通过一定规模放养贝类对整个蓄水池中悬浮物的沉积效果.结果表明,在适宜的温度条件下( 17~25℃),太平洋牡蛎对蓄水池水中悬浮物生物沉积速率为1.08~1.32 g/(ind-d),紫贻贝为0.65~0.85 g/(ind-d).通过在蓄水池中大量吊笼养贝类,蓄水池中贝类养殖区的悬浮物沉降

  16. Uncovering the Complex Transcriptome Response of Mytilus chilensis against Saxitoxin: Implications of Harmful Algal Blooms on Mussel Populations

    Science.gov (United States)

    Detree, Camille; Núñez-Acuña, Gustavo; Roberts, Steven; Gallardo-Escárate, Cristian

    2016-01-01

    Saxitoxin (STX), a principal phycotoxin contributing to paralytic shellfish poisoning, is largely produced by marine microalgae of the genus Alexandrium. This toxin affects a wide range of species, inducing massive deaths in fish and other marine species. However, marine bivalves can resist and accumulate paralytic shellfish poisons. Despite numerous studies on the impact of STX in marine bivalves, knowledge regarding STX recognition at molecular level by benthic species remains scarce. Therefore, the aim of this study was to identify novel genes that interact with STX in the Chilean mussel Mytilus chilensis. For this, RNA-seq and RT-qPCR approaches were used to evaluate the transcriptomic response of M. chilensis to a purified STX as well as in vivo Alexandrium catenella exposure. Approximately 800 million reads were assembled, generating 138,883 contigs that were blasted against the UniProt Mollusca database. Pattern Recognition Receptors (PRRs) involved in mussel immunity, such as Toll-like receptors, tumor necrosis factor receptors, and scavenger-like receptors were found to be strongly upregulated at 8 and 16 h post-STX injection. These results suggest an involvement of PRRs in the response to STX, as well as identifying potential, novel STX-interacting receptors in this Chilean mussel. This study is the first transcriptomic overview of the STX-response in the edible species M. chilensis. However, the most significant contribution of this work is the identification of immune receptors and pathways potentially involved in the recognition and defense against STX’s toxicity and its impact of harmful algae blooms on wild and cultivated mussel populations. PMID:27764234

  17. Bivalve reefs from the Upper Triassic of Iran

    Directory of Open Access Journals (Sweden)

    Franz T. Fürsich

    2005-10-01

    Full Text Available In the Upper Triassic Nayband Formation of east-central Iran, bivalves repeatedly form small patch reefson a mid to outer mixed carbonate-siliciclastic ramp in close stratigraphic neighbourhood to coral and coralspongereefs. In contrast to other Triassic-Jurassic bivalve-dominated patch reefs, the bivalve reefs of theNayband Formation are characterized by a comparatively high diversity of framebuilding taxa. These includetaxa from three different families, i.e., the ostreids Umbostrea emamii, U. iranica and U.? aff. parasiticum, the prospondylids Newaagia stocklini and Persia monstrosa, and the plicatulids Eoplicatula parvadehensis and Pseudoplacunopsis asymmetrica. The bivalve reef constructors may have had a competitive advantage over coral and calcareous sponges in environments characterized by a higher degree of turbidity and/or higher nutrient contents.

  18. Persistent free radical ESR signals in marine bivalve tissues. [Electron Spin Resonance (ESR)

    Energy Technology Data Exchange (ETDEWEB)

    Mehlorn, R.J. (California Univ., Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering); Mendez, A.T. (Fundacion Educativa Ana G. Mendez, Rio Piedras (Puerto Rico)); Higashi, R. (California Univ., Bodega Bay, CA (United States). Bodega Marine Lab.); Fan, T. (California Univ., Davis, CA (United States))

    1992-08-01

    Freeze-dried homogenates of the oyster Crassostrea rhizophorae collected from waters in Puerto Rico near urban and industrial sites as well as at relatively pristine locations yielded electron spin resonance (ESR) spectra characteristic of free radicals as well as spectral components of transition metal ions, dominated by manganese. The magnitudes of these ESR signals and the concentrations of trace elements (determined by X-ray fluorescence) varied considerably among oyster samples, masking any potential correlation with polluted waters. Laboratory studies were initiated to identify the factors controlling the magnitudes of the tissue free radical ESR signals. Another mollusc, Mytilus californianus collected at the Bodega Marine laboratory in northern California, was fractionated into goneds and remaining tissue. Freeze-dried homogenates of both fractions exhibited ESR signals that increased gradually with time. ESR signals were observed in freeze-dried perchloric acid (PCA) precipitates of the homogenates, delipidated PCA precipitates, and in chloroform extracts of these precipitates. Acid hydrolysis to degrade proteins to amino acids produced a residue, which yielded much larger ESR free radical signals after freeze-drying. Freshly thawed homogenates of Crassostrea rhizophorae also exhibited ESR signals. A laboratory model of copper stress in Crassostrea rhizophorae was developed to study the effect of this transition metal on dssue free radicals. Preliminary results suggested that sublethal copper exposure had little effect on tissue fire radicals, except possibly for a signal enhancement in an oyster fraction that was enriched in kidney granules. Since kidney granules are known to accumulate heavy metals in mussels and probably other marine bivalves, this signal enhancement may prove to be an indicator of free radical processes associated with heavy metal deposition in molluscs.

  19. Isotopic fingerprints of bacterial chemosymbiosis in the bivalve Loripes lacteus

    Science.gov (United States)

    Dreier, A.; Stannek, L.; Blumenberg, M.; Taviani, M.; Sigovini, M.; Wrede, C.; Thiel, V.; Hoppert, M.

    2012-04-01

    Metazoans with chemosynthetic bacterial endosymbionts are widespread in marine habitats and respective endosymbioses are known from seven recent animal phyla. However, little is known about endosymbioses in fossil settings and, hence, ecological significance in earth history. In the presented project, we investigate the ancient and recent bivalve fauna living at marine sedimentary oxic/anoxic interfaces. Two bivalve species collected from the same benthic environment - a Mediterranean lagoon - were studied in detail. The diet of Loripes lacteus is based on thiotrophic gill symbionts whereas Venerupis aureus is a filter feeding bivalve without symbionts. The presence of three key enzymes from sulfur oxidation (APS-reductase), carbon fixation (RubisCO) and assimilation of nitrogen (glutamine synthetase [GS]) were detected by immunofluorescence in symbionts of Loripes and/or by activity tests in living specimens. In search of biosignatures associated with thiotrophic chemosymbionts that might be suitable for detection of chemosymbiotic diets in recent and fossil bivalve shells, we analyzed the isotopic composition of shell lipids (δ13C) and the bulk organic matrix of the shell (δ13C, δ15N, δ34S). We could show that the combined δ15N and δ13C values from shell extracts are stable in subfossil (Pleistocene) bivalve specimens, as long as the isotopic data is "calibrated" with respective signatures from a filter feeding bivalve sampled from the same site or lithostratigraphic bed.

  20. Co-option of bacteriophage lysozyme genes by bivalve genomes

    Science.gov (United States)

    Wang, Chunyang; Jin, Min; Lan, Jiangfeng; Ye, Ting; Hui, Kaimin; Tan, Jingmin; Wang, Zheng; Wang, Wen; Han, Guan-Zhu

    2017-01-01

    Eukaryotes have occasionally acquired genetic material through horizontal gene transfer (HGT). However, little is known about the evolutionary and functional significance of such acquisitions. Lysozymes are ubiquitous enzymes that degrade bacterial cell walls. Here, we provide evidence that two subclasses of bivalves (Heterodonta and Palaeoheterodonta) acquired a lysozyme gene via HGT, building on earlier findings. Phylogenetic analyses place the bivalve lysozyme genes within the clade of bacteriophage lysozyme genes, indicating that the bivalves acquired the phage-type lysozyme genes from bacteriophages, either directly or through intermediate hosts. These bivalve lysozyme genes underwent dramatic structural changes after their co-option, including intron gain and fusion with other genes. Moreover, evidence suggests that recurrent gene duplication occurred in the bivalve lysozyme genes. Finally, we show the co-opted lysozymes exhibit a capacity for antibacterial action, potentially augmenting the immune function of related bivalves. This represents an intriguing evolutionary strategy in the eukaryote–microbe arms race, in which the genetic materials of bacteriophages are co-opted by eukaryotes, and then used by eukaryotes to combat bacteria, using a shared weapon against a common enemy. PMID:28100665

  1. Bioaccumulation and retention of lead in the mussel Mytilus galloprovincialis following uptake from seawater

    Energy Technology Data Exchange (ETDEWEB)

    Boisson, Florence; Cotret, Olivier; Fowler, Scott W. [International Atomic Energy Agency, Marine Environment Laboratory, 4 Quai Antoine Ier, BP 800, MC-98012 Monaco (France)

    1998-10-15

    Bioaccumulation of lead in the mussel Mytilus galloprovincialis from {sup 210}Pb-labeled bulk seawater (dissolved and particulate pathways combined) was examined over 21 days. The lead bioaccumulation factor (BAF) at equilibrium was estimated to be 211{+-}10 ml g{sup -1}. This value was two orders of magnitude lower than BAFs reported in the literature for other trace metals in this bivalve indicating that lead is not efficiently accumulated by mussels from bulk seawater. The resultant lead distribution in mussels was 49{+-}10% in soft tissues and 46{+-}16% in the shell suggesting similar uptake rates (Bq day{sup -1}) in both compartments throughout the exposure. Total elimination for lead in mussels was adequately described by a short-term compartment with a biological half-life for loss of 1.4{+-}0.3 days and a long-term compartment which released lead only very slowly (T{sub b1/2}=2.5{+-}0.7 months). No difference was noted for lead elimination rates in shell and in soft parts. When experimentally exposed to lead under conditions representative of natural environmental lead levels in water, including both that in the dissolved phase and in the food, the shell compartment was shown to contain the major fraction of the total lead accumulated by mussels. Therefore mussels may be considered as good bioindicators of lead contamination accumulated from the dissolved rather than from the particulate source. Furthermore, the relatively slow uptake and the long depuration half-life of lead will limit the ability of mussels to accurately record short-term variations in lead concentrations in the surrounding waters, a fact that should be taken into consideration in order to define the appropriate sampling frequency for mussels used in biomonitoring programs involving lead

  2. Embryotoxicity of TiO2 nanoparticles to Mytilus galloprovincialis (Lmk).

    Science.gov (United States)

    Libralato, Giovanni; Minetto, Diego; Totaro, Sara; Mičetić, Ivan; Pigozzo, Andrea; Sabbioni, Enrico; Marcomini, Antonio; Volpi Ghirardini, Annamaria

    2013-12-01

    Few data exist on the ecotoxicological effects of nanosized titanium dioxide (nTiO2) towards marine species with specific reference to bivalve molluscs and their relative life stages. Mytilus galloprovincialis Lamarck was selected to assess the potential adverse effects of nTiO2 (0-64 mg/L) on its early larval development stages (pre-D shell stage, malformed D-shell stage and normal D-shell stage larvae) considering two exposure scenarios characterised by total darkness (ASTM protocol) and natural photoperiod (light/dark). This approach was considered to check the presence of potential effects associated to the photocatalytic properties of nTiO2. Parallel experiments were carried on with the bulk reference TiCl4. The toxicity of nTiO2 showed to be mainly related to its "nano" condition and to be influenced by the exposure to light that supported the increase in the number of pre-D shell stage (retarded) larvae compared to the malformed ones especially at the maximum effect concentrations (4 and 8 mg nTiO2/L). The non-linear regression toxicity data analysis showed the presence of two EC50 values per exposure scenario: a) EC(50)1 = 1.23 mg/L (0.00-4.15 mg/L) and EC(50)2 = 38.56 mg/L (35.64-41.47 mg/L) for the dark exposure conditions; b) EC(50)1 = 1.65 mg/L (0.00-4.74 mg/L) and EC(50)2 = 16.39 mg/L (13.31-19.48 mg/L) for the light/dark exposure conditions. The potential implication of agglomeration and sedimentation phenomena on ecotoxicological data was discussed.

  3. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Science.gov (United States)

    Balseiro, Pablo; Falcó, Alberto; Romero, Alejandro; Dios, Sonia; Martínez-López, Alicia; Figueras, Antonio; Estepa, Amparo; Novoa, Beatriz

    2011-01-01

    Previous research has shown that an antimicrobial peptide (AMP) of the myticin class C (Myt C) is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH) libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme). Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped). Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  4. Mytilus galloprovincialis myticin C: a chemotactic molecule with antiviral activity and immunoregulatory properties.

    Directory of Open Access Journals (Sweden)

    Pablo Balseiro

    Full Text Available Previous research has shown that an antimicrobial peptide (AMP of the myticin class C (Myt C is the most abundantly expressed gene in cDNA and suppressive subtractive hybridization (SSH libraries after immune stimulation of mussel Mytilus galloprovincialis. However, to date, the expression pattern, the antimicrobial activities and the immunomodulatory properties of the Myt C peptide have not been determined. In contrast, it is known that Myt C mRNA presents an unusual and high level of polymorphism of unidentified biological significance. Therefore, to provide a better understanding of the features of this interesting molecule, we have investigated its function using four different cloned and expressed variants of Myt C cDNA and polyclonal anti-Myt C sera. The in vivo results suggest that this AMP, mainly present in hemocytes, could be acting as an immune system modulator molecule because its overexpression was able to alter the expression of mussel immune-related genes (as the antimicrobial peptides Myticin B and Mytilin B, the C1q domain-containing protein MgC1q, and lysozyme. Moreover, the in vitro results indicate that Myt C peptides have antimicrobial and chemotactic properties. Their recombinant expression in a fish cell line conferred protection against two different fish viruses (enveloped and non-enveloped. Cell extracts from Myt C expressing fish cells were also able to attract hemocytes. All together, these results suggest that Myt C should be considered not only as an AMP but also as the first chemokine/cytokine-like molecule identified in bivalves and one of the few examples in all of the invertebrates.

  5. Total antioxidant capacity in the black mussel ( Mytilus galloprovincialis) from Black Sea coasts

    Science.gov (United States)

    Moncheva, S.; Trakhtenberg, S.; Katrich, E.; Zemser, M.; Goshev, I.; Toledo, F.; Arancibia-Avila, P.; Doncheva, V.; Gorinstein, S.

    2004-03-01

    The aim of this investigation was to evaluate the total antioxidant radical scavenging capacity (TARSC) in tissue extracts for understanding biochemical adaptations involving the antioxidant defense system of a bivalve mussel, Mytilus galloprovincialis, sampled in polluted (Pol) and non-polluted (Npol) sites from Black Sea coasts. Antioxidant-rich polyphenol fractions were extracted from whole dry mussel tissue with methanol and water in different proportions. The extracts were screened for polyphenol content and their potential as antioxidants using various in vitro models, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH rad ), β-carotene-linoleate (β-carotene) and nitric oxide (NO rad ). The total polyphenol extract of the whole mussel tissue from polluted site (TPMEPol) showed the highest antioxidant capacity among all of the extracts with the tested methods and was comparable with the antioxidant capacity of butylated hydroxyanisole (BHA). The antioxidant capacities of this extract determined by DPPH rad , β-carotene and NO rad methods and polyphenol content showed the highest correlation coefficients ( R2) such as 0.9985, 0.9915 and 0.9895, respectively. The free polyphenol extracts (FPMEPol and FPMENPol) had lower antioxidant capacity than the two others of total polyphenols (TPMEPol and TPMENPol) with three scavenging methods. Responses were linear in all tested methods and the antioxidant capacity values of soluble antioxidants showed the following relative order: Trolox>BHA>TPMEPol>TPMENPol>FPMEPol>FPMENPol. Nutritional antioxidants, such as polyphenols, were probably the main antioxidant contribution to mussel antioxidants. The mussel extracts from the polluted site exhibited higher antioxidant capacity than from the non-polluted one. The results presented in this report indicate that the antioxidant capacity of the whole tissue of the mussel extract could possibly be a useful biomarker for aquatic environments.

  6. Immune responses during the larval stages of Mytilus galloprovincialis: metamorphosis alters immunocompetence, body shape and behavior.

    Science.gov (United States)

    Balseiro, Pablo; Moreira, Rebeca; Chamorro, Rubén; Figueras, Antonio; Novoa, Beatriz

    2013-08-01

    We investigated the development of the immune system during the larval stages of the mussel Mytilus galloprovincialis. The ability of trochophore and veliger larvae to phagocytose foreign particles (Escherichia coli and zymosan) was measured. Phagocytosis was detected as early as 24 h post-fertilization (hpf) using flow cytometry and fluorescence microscopy. However, although there was a high basal production of reactive oxygen and nitrogen species (ROS and NRS), the phagocytosis of zymosan did not trigger an associated increase in radical production. In addition, a panel of immune-related mussel genes (Myticin B, Myticin C, Mytilin B, Mytimycin precursor 1, Macrophage migration inhibition factor, lysozyme, C1q, membrane attack complex protein and fibrinogen-related protein) was selected for expression profile analysis throughout the different developmental stages (trochophore, veliger, metamorphosis, post-settlement and spat). The expression of these genes increased during the transition from trochophore to spat, and the level of expression was higher in oocytes than in trochophores, suggesting that gene expression during the first larval stages might be maternal in origin. Metamorphosis was identified as a crucial stage when larvae increased the expression of immune-related genes and responded to environmental signals. Whole-mount in situ hybridization studies showed the mantle edge as an important area in the development of immunocompetence in bivalve larvae. Larvae responded to both live and heat-inactivated bacteria by modulating expression of immune-related genes. Altogether, our results support that during the early stages of M. galloprovincialis development, immune mechanisms emerge to aid larvae in managing infections.

  7. Marine bivalve shell geochemistry and ultrastructure from modern low pH environments: environmental effect versus experimental bias

    Science.gov (United States)

    Hahn, S.; Rodolfo-Metalpa, R.; Griesshaber, E.; Schmahl, W. W.; Buhl, D.; Hall-Spencer, J. M.; Baggini, C.; Fehr, K. T.; Immenhauser, A.

    2012-05-01

    Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy) were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island. Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

  8. Marine bivalve shell geochemistry and ultrastructure from modern low pH environments: environmental effect versus experimental bias

    Directory of Open Access Journals (Sweden)

    S. Hahn

    2012-05-01

    Full Text Available Bivalve shells can provide excellent archives of past environmental change but have not been used to interpret ocean acidification events. We investigated carbon, oxygen and trace element records from different shell layers in the mussels Mytilus galloprovincialis combined with detailed investigations of the shell ultrastructure. Mussels from the harbour of Ischia (Mediterranean, Italy were transplanted and grown in water with mean pHT 7.3 and mean pHT 8.1 near CO2 vents on the east coast of the island. Most prominently, the shells recorded the shock of transplantation, both in their shell ultrastructure, textural and geochemical record. Shell calcite, precipitated subsequently under acidified seawater responded to the pH gradient by an in part disturbed ultrastructure. Geochemical data from all test sites show a strong metabolic effect that exceeds the influence of the low-pH environment. These field experiments showed that care is needed when interpreting potential ocean acidification signals because various parameters affect shell chemistry and ultrastructure. Besides metabolic processes, seawater pH, factors such as salinity, water temperature, food availability and population density all affect the biogenic carbonate shell archive.

  9. Distribution and growth of Vibrio parahaemolyticus in southern Chilean clams (Venus antiqua) and blue mussels (Mytilus chilensis).

    Science.gov (United States)

    Aranda, Carlos P; Yévenes, Marco; Rodriguez-Benito, Cristina; Godoy, Félix A; Ruiz, Magdalena; Cachicas, Viviana

    2015-01-01

    We evaluated the distribution and growth of Vibrio parahaemolyticus in the inland sea of southern Chile, where the world's largest foodborne gastroenteritis outbreak by the pandemic strain O3:K6 occurred in 2005. Intertidal samples of Mytilus chilensis and Venus antiqua were collected around port towns between 41°28'S and 43°07'S, during April to May 2011 and January to March 2012. We used most probable number real-time polymerase chain reaction (MPN-PCR) for enumeration of the tlh, tdh, and trh genes in freshly harvested bivalves and after a controlled postharvest temperature abuse. Pathogenic markers (tdh+ or trh+) were not detected. Total V. parahaemolyticus (tlh+) in freshly harvested samples reached up to 0.38 and 3.66 log MPN/g in 2011 and 2012, respectively, with values close to or above 3 log MPN/g only near Puerto Montt (41°28'S, 72°55'W). Enrichments by temperature abuse (>2 log MPN/g) occurred mainly in the same zone, regardless of the year, suggesting that both natural or anthropogenic exposure to high temperatures were more critical. Lower salinity and higher sea surface temperature in Reloncaví Sound and Reloncaví Estuary were consistent with our observations and allowed confirmation of the existence of a high-risk zone near Puerto Montt. Based on the results, a strategy focused on risk management inside this defined hazard zone is recommended.

  10. A protein binding site in the M mitochondrial genome of Mytilus galloprovincialis may be responsible for its paternal transmission.

    Science.gov (United States)

    Kyriakou, Eleni; Kravariti, Lara; Vasilopoulos, Themistoklis; Zouros, Eleftherios; Rodakis, George C

    2015-05-10

    Sea mussels (genus Mytilus) have two mitochondrial genomes in obligatory co-existence, one that is transmitted through the egg and the other through the sperm. The phenomenon, known as Doubly Uniparental Inheritance (DUI) of mitochondrial DNA (mtDNA), is presently known to occur in more than 40 molluscan bivalve species. Females and the somatic tissues of males contain mainly the maternal (F) genome. In contrast, the sperm contains only the paternal (M) genome. Through electrophoretic mobility shift assay (EMSA) experiments we have identified a sequence element in the control region (CR) of the M genome that acts as a binding site for the formation of a complex with a protein factor that occurs in the male gonad. An adenine tract upstream to the element is also essential for the formation of the complex. The reaction is highly specific. It does not occur with protein extracts from the female gonad or from a male or female somatic tissue. Further experiments showed that the interaction takes place in mitochondria surrounding the nucleus of the cells of male gonads, suggesting a distinct role of perinuclear mitochondria. We propose that at a certain point during spermatogenesis mitochondria are subject to degradation and that perinuclear mitochondria with the M mtDNA-protein complex are protected from this degradation with the result that mature spermatozoa contain only the paternal mitochondrial genome.

  11. ANTIBIOTIC RESISTANT BACTERIA FROM HALIOTIS TUBERCULATA AND MYTILUS GALLOPROVINCIALIS

    Directory of Open Access Journals (Sweden)

    F. Conte

    2009-12-01

    Full Text Available The antibiotic resistance (AR of Gram negative bacteria from Haliotis tuberculata (Ht and Mytilus galloprovincialis (Mg was assessed. Essential differences between R profiles of Pseudomonas spp and of other strains was not observed. Strains AR from Ht and Mg was similar.

  12. Antiallergic herbal composition from Scutellaria baicalensis and Phyllostachys edulis.

    Science.gov (United States)

    Kim, Dong-Seon; Son, Eun-Jung; Kim, Miran; Heo, Young-Moon; Nam, Jeong-Bum; Ro, Jai Youl; Woo, Sung-Sick

    2010-05-01

    We aimed to find antiallergic agents from natural sources using mast cells activated during allergic reaction. We screened over 2000 plants for blockade of histamine release and identified two of them, S. baicalenesis and P. edulis. Bioassay-guided fractionation led to two main constituent flavonoids, baicalin from S. baicalenesis roots and isoorientin from P. edulis leaves. Based on these two compounds, two standardized extracts (SSBE and SPEE) and a combined standardized herb composition (SHC) were developed. SSBE, SPEE, and SHC remarkably inhibited histamine and leukotriene release from mast cells activated by anti-OVA/OVA binding, and SHC showed a stronger inhibition than either extract alone. SHC also showed greater inhibition potency than either aspirin or cromolyn, which are known antiallergic agents. Our results suggest that SHC reduce degranulation during mast cell activation and could be a promising candidate for the treatment of immune/allergic diseases related to mast cells.

  13. The complete plastid genome sequence of Bomarea edulis (Alstroemeriaceae: Liliales).

    Science.gov (United States)

    Kim, Jung Sung; Kim, Hyoung Tae; Yoon, Chang Young; Kim, Joo-Hwan

    2016-05-01

    Bomarea, a member of the family Alstroemeriaceae, is distributed from Chile to Mexico and includes approximately 120 species. Recent molecular phylogenetic studies have clarified the monophyly of the family within the order Liliales and the sister relationship with the family Colchicaceae. At this time, five plastid genomes of Liliales have been analyzed at the familial level. To examine plastid genome variation at the generic level, we sequenced the plastid genome of Bomarea edulis, which is the most widely distributed species in the genus, and compared it with Alstroemeria aurea. The plastid genome sequence of B. edulis was 154,925 bp in length with a similar structure as A. aurea, excluding the IR-LSC junction. Ycf68 and infA were pseudogenes caused by frameshift mutations, and the ycf15 gene was deleted, similar to A. aurea.

  14. COMPARISON OF RNA EXTRACTION METHODS FOR Passiflora edulis SIMS LEAVES

    OpenAIRE

    2016-01-01

    ABSTRACT Functional genomic analyses require intact RNA; however, Passiflora edulis leaves are rich in secondary metabolites that interfere with RNA extraction primarily by promoting oxidative processes and by precipitating with nucleic acids. This study aimed to analyse three RNA extraction methods, Concert™ Plant RNA Reagent (Invitrogen, Carlsbad, CA, USA), TRIzol® Reagent (Invitrogen) and TRIzol® Reagent (Invitrogen)/ice -commercial products specifically designed to extract RNA, and...

  15. Actividad hipoglucemiante de Bouvardia terniflora, Brickellia veronicaefolia y Parmentiera edulis Hypoglicemic activity of Bouvardia terniflora, Brickellia veronicaefolia and Parmentiera edulis

    Directory of Open Access Journals (Sweden)

    Rosa Martha Pérez-Gutiérrez

    1998-07-01

    Full Text Available Objetivo. Evaluar la actividad hipoglucemiante de los extractos de hexano, cloroformo y metanol de Brickellia veronicaefolia, Bouvardia terniflora y Parmentiera edulis. Material y métodos. Se probaron los extractos de las plantas (100, 200 y 300 mg/kg, vía intraperitoneal en ratones normoglucémicos y con diabetes inducida con aloxana. Resultados. La administración de 300 mg/kg de los extractos clorofórmicos de P. edulis, B. terniflora y hexánico de B. veronicaefolia en ratones diabéticos disminuye el nivel de glucosa sanguínea en 43.75, 58.56 y 72.13%, respectivamente. Estos extractos (300 mg/kg, administrados en ratones normoglucémicos, reducen la glucosa sanguínea en 29.61, 33.42 y 39.84%, respectivamente. Conclusiones. Con este estudio se confirma la actividad hipoglucemiante de estas plantas usadas en la medicina tradicional para el tratamiento de la diabetes.Objective. To evaluate the hypoglycemic activity of the hexane, chloroform and methanol extracts of Bouvardia terniflora, Brickelia veronicaefolia and Parmentiera edulis. Material and methods. Normal and alloxan-induced diabetic mice were administered these plant extracts (intraperitoneal 100, 200 and 300 mg/kg. Results. The administration of 300 mg/kg of chloroform extracts from P. edulis and B. terniflora and hexane from B. veronicaefolia to diabetic mice decreased the blood glucose levels in 43.75, 58.56 and 72.13%, respectively. These extracts administered to normal mice reduced blood glucose levels in 29.61, 33.42 and 39.84%, respectively. Conclusions. The hypoglycemic effect of these plant extracts used in traditional medicine for diabetes treatment is confirmed.

  16. Modeling the carbon isotope composition of bivalve shells (Invited)

    Science.gov (United States)

    Romanek, C.

    2010-12-01

    The stable carbon isotope composition of bivalve shells is a valuable archive of paleobiological and paleoenvironmental information. Previous work has shown that the carbon isotope composition of the shell is related to the carbon isotope composition of dissolved inorganic carbon (DIC) in the ambient water in which a bivalve lives, as well as metabolic carbon derived from bivalve respiration. The contribution of metabolic carbon varies among organisms, but it is generally thought to be relatively low (e.g., organism and high (>90%) in the shells from terrestrial organisms. Because metabolic carbon contains significantly more C-12 than DIC, negative excursions from the expected environmental (DIC) signal are interpreted to reflect an increased contribution of metabolic carbon in the shell. This observation contrasts sharply with modeled carbon isotope compositions for shell layers deposited from the inner extrapallial fluid (EPF). Previous studies have shown that growth lines within the inner shell layer of bivalves are produced during periods of anaerobiosis when acidic metabolic byproducts (e.g., succinic acid) are neutralized (or buffered) by shell dissolution. This requires the pH of EPF to decrease below ambient levels (~7.5) until a state of undersaturation is achieved that promotes shell dissolution. This condition may occur when aquatic bivalves are subjected to external stressors originating from ecological (predation) or environmental (exposure to atm; low dissolved oxygen; contaminant release) pressures; normal physiological processes will restore the pH of EPF when the pressure is removed. As a consequence of this process, a temporal window should also exist in EPF at relatively low pH where shell carbonate is deposited at a reduced saturation state and precipitation rate. For example, EPF chemistry should remain slightly supersaturated with respect to aragonite given a drop of one pH unit (6.5), but under closed conditions, equilibrium carbon isotope

  17. Pengaruh Pemanfaatan Rumput Laut Gracilaria Edulis dalam Pakan terhadap Kinerja Ayam Fase Pullet (The Influence of Seaweed Gracilaria Edulis in the Diets on the Performance of Pullet

    Directory of Open Access Journals (Sweden)

    Wiesje Martha Horhoruw

    2012-02-01

    ppm; 0.50 ppm; 0.52 ppm; 0.55 ppm; 0.56 ppm and 0.60 ppm. It was concluded that the use of seaweed Gracilaria edulis until 15.00% in the diet did not decrease the performance of pullet phase and increased egg yolk color, also did not increase iodine in the yolk. (Key words: Seaweed Gracilaria edulis, Diets, Chicken’s work, Pullet phase

  18. Additions to the Marine bivalve mollusks of Peru

    Directory of Open Access Journals (Sweden)

    Carlos Paredes

    2013-06-01

    Full Text Available The following species of marine bivalve mollusks were recorded for the first time from the Peruvian sea: Glycymeris (Axinactus delessertii (Reeve, 1843; Botula cylista Berry, 1959; Parahyotissa (Pliohyotissa quercinus (Sowerby II, 1871; Pitar (Pitar helenae Olsson, 1961; Eurhomalea lenticularis (Sowerby I, 1835; and Cardiomya planetica (Dall, 1908. Description, habitat and the geographical distribution are cited for each species.

  19. The adaptive value of migrations for the bivalve Macoma balthica

    NARCIS (Netherlands)

    Hiddink, Johan Gerrit

    2002-01-01

    This thesis is about the movements of the coastal marine bivalve Macoma balthica. M. balthica migrates over several kilometres between nurseries at high tidal flats, where juveniles are found in high numbers, and the adult habitat on low-lying tidal flats. Most benthic species in the Wadden Sea have

  20. Molecular approaches to bivalve population studies: a review

    Directory of Open Access Journals (Sweden)

    Dragomir-Cosmin David

    2011-12-01

    Full Text Available This paper presents a literature review concerning the importance of molecular approaches in bivalve’s population study. The class Bivalvia counts more than 20,000 species with a wide distribution both in freshwater and marine environment. Given their importance especially in aquaculture as a source of food, they have also a strong economic impact upon human society. This review encompasses best practices in bivalve studies from field sampling to laboratory analyses, addressing questions about molecular methods and tools commonly used by specialized researchers. Molecular tools specifically deals with phylogeography, population genetics, biology, ecology and taxonomy. In all these fields, molecular markers play an important role by completing some unanswered questions such as the role of the bivalves in the ecosystems in relation to anthropogenic and global change issues. Numerous genetic markers were developed for specific problems, thereferore we identify as a major issue the absence of uniform and universally recognized methods. The various sections of the paper emphasize from peer reviewed literature literature which are considered the most useful markers, costs and benefits of different methodology, major gaps of knowledge.in bivalve population studies. By reviewing virtually all genetic markers employed during nearly half a century of bivalve molecular research, in our opinion two are the best option “tools: the mitochondrial COI (cytochrome oxidase subunit I and nuclear ITS2 (internal transcribed spacer 2.

  1. The Holocene and Recent marine Bivalve Mollusca of Surinam

    NARCIS (Netherlands)

    Regteren Altena, van C.O.

    1968-01-01

    As the preparation of an annotated check list of the marine Mollusca of Surinam (Dutch Guiana) will take some more years, it was thought appropriate to publish a preliminary report on the bivalves. This report consists of a list of 126 species with a few notes containing, i.a., the description of se

  2. Lower Carboniferous marine bivalves from the Cantabrian Mountains (Spain)

    NARCIS (Netherlands)

    Amler, M.R.W.; Winkler Prins, C.F.

    1999-01-01

    The Lower Carboniferous bivalves of the Vegamián and Genicera formations are described, followed by a brief discussion on palaeoenvironmental and palaeogeographical aspects. The black shales of the Vegamián Fm. (Tournaisian) yield a peculiar association of euchondriid taxa (Euchondria wagneri sp. no

  3. Artificially evolved functional shell morphology of burrowing bivalves

    DEFF Research Database (Denmark)

    Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

    2014-01-01

    dimensional (3D) objects, the first ever artificial evolution of a physical bivalve shell was performed. The result was a vertically flattened shell occupying only the top sediment layers. Insufficient control of the sediment was the major limitation of the setup and restricted the significance of the results...

  4. EFECTOS DE LA VARIACIÓN ALTITUDINAL SOBRE LA POLINIZACIÓN EN CULTIVOS DE GULUPA (Passiflora edulis F. edulis Effects of Altitudinal Variation on Pollination in Purple Passion Fruit Crops (Passiflora edulis F. edulis

    Directory of Open Access Journals (Sweden)

    JULIÁN MEDINA-GUTIÉRREZ

    2012-05-01

    Full Text Available El propósito de este trabajo es reconocer y diferenciar las especies visitantes y los verdaderos polinizadores de dos cultivos de gulupa (Passiflora edulis f. edulis Sims. ubicados a diferente altitud (2225 msnm y 1657 msnm en el municipio de Buenavista - Boyacá cordillera Oriental de Colombia. En los dos cultivos se encontraron diferencias en composición, en número de visitantes y en polinizadores. En el cultivo ubicado a 2225 msnm, se registraron siete especies, mientras que en el cultivo ubicado a 1657 msnm, se encontraron 18 especies de visitantes. Se realizaron observaciones del recurso colectado por los visitantes y la estructura floral con la que el visitante entra en contacto. Además, se realizaron cuatro tratamientos experimentales de biología floral: polinización pasiva, polinización natural, polinización manual y eficiencia de polinizadores mediante "visitas únicas", concluyendo que las especies polinizadoras son: en C1 Apis mellifera, y en C2 Xylocopa frontalis, Xylocopa lachnea y Epicharis sp.The purpose of this paper is to study in two crops of purple passionfruit Passiflora edulis f. edulis harvested at different altitudes (2225 m.a.s.l. and 1657 m.a.s.l. in the municipality of Buenavista - Boyacá, located in the eastern Mountain range of Colombia, in order to familiarize with visitors and pollinators. This study reveals that in both crops there were differences found in composition, the number of visitors and pollinators. In the crop at 2225 m.a.s.l., 7 species were registered, while 18 species were recorded at the 1657 m.a.s.l. crop. In order to achieve this, collected material by the visitors and the floral structures with which they approach, were observed; at the same time four experiments took place: passive pollination, natural pollination, manual pollination and pollinator's efficiency. These experiments established that pollinator species are: in C1 Apis mellifera, and in C2 and Xylocopa frontalis, Xylocopa

  5. Feeding traits of the European flat oyster, Ostrea edulis, and the invasive Pacific oyster, Crassostrea gigas

    DEFF Research Database (Denmark)

    Nielsen, Mette; Hansen, Benni Winding; Vismann, Bent

    2016-01-01

    Two oysters, the native flat oyster, Ostrea edulis, and the non-indigenous Pacific oyster, Crassostrea gigas, have partially overlapping distributions in European waters. Relatively little is known about particle selection by O. edulis, and the goal of the present study was to establish baselines...... °C and a salinity of 25. The CR of O. edulis was one to three times lower than that of C. gigas for the three smaller algal species (5−15 µm) but not different for the two larger algae. Algae in the size range 7−32 µm were retained with 100% RE by both oysters, but the smallest alga was retained...

  6. Physico-chimie des fruits du safoutier (Dacryodes edulis camerounais

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    Kapseu, C.

    1999-01-01

    Full Text Available Physico-Chemistry of Cameroonian Safou Tree Fruits Dacryodes edulis. Safou tree (Dacryodes edulis is a part of the agrarian landscapes of tropical countries. Although it is known as a multiple purposes tree, it is still underexploited. This is due to the lack of scientific knowledge and data. The aim of this work is to determine the physicochemical properties of safou tree fruits. These fruits, called safou, are consumed less than two days after harvest. The morphologic character vary according to the area and the types. In Cameroon, oil content varies from 47.4 to 61.1 % according to the agro-climatic areas : soudano saharian, high lands and continental area. The fatty acid composition of the oil, determined by gas chromatographie on capillary column, is rich in palmatic acid (35.4-46.0 % of total fatty acids and in oleic acid (27.2-39.8 %. Analysis of triglycerides shows that 4 triglycerides only represent more than 70 % of total triglycerides : palmitodiolein (19.2-27 %, dipalmito-olein (16.8-26.1 %, palmito-oleo-linolein (14.7-18.5 %, dipalmito-linolein (10.5-17.6 %.

  7. COMPARISON OF RNA EXTRACTION METHODS FOR Passiflora edulis SIMS LEAVES

    Directory of Open Access Journals (Sweden)

    ANNY CAROLYNE DA LUZ

    2016-02-01

    Full Text Available ABSTRACT Functional genomic analyses require intact RNA; however, Passiflora edulis leaves are rich in secondary metabolites that interfere with RNA extraction primarily by promoting oxidative processes and by precipitating with nucleic acids. This study aimed to analyse three RNA extraction methods, Concert™ Plant RNA Reagent (Invitrogen, Carlsbad, CA, USA, TRIzol® Reagent (Invitrogen and TRIzol® Reagent (Invitrogen/ice -commercial products specifically designed to extract RNA, and to determine which method is the most effective for extracting RNA from the leaves of passion fruit plants. In contrast to the RNA extracted using the other 2 methods, the RNA extracted using TRIzol® Reagent (Invitrogen did not have acceptable A260/A280 and A260/A230 ratios and did not have ideal concentrations. Agarose gel electrophoresis showed a strong DNA band for all of the Concert™ method extractions but not for the TRIzol® and TRIzol®/ice methods. The TRIzol® method resulted in smears during electrophoresis. Due to its low levels of DNA contamination, ideal A260/A280 and A260/A230 ratios and superior sample integrity, RNA from the TRIzol®/ice method was used for reverse transcription-polymerase chain reaction (RT-PCR, and the resulting amplicons were highly similar. We conclude that TRIzol®/ice is the preferred method for RNA extraction for P. edulis leaves.

  8. Actividad hipoglucemiante de Bouvardia terniflora, Brickellia veronicaefolia y Parmentiera edulis

    Directory of Open Access Journals (Sweden)

    Pérez-Gutiérrez Rosa Martha

    1998-01-01

    Full Text Available Objetivo. Evaluar la actividad hipoglucemiante de los extractos de hexano, cloroformo y metanol de Brickellia veronicaefolia, Bouvardia terniflora y Parmentiera edulis. Material y métodos. Se probaron los extractos de las plantas (100, 200 y 300 mg/kg, vía intraperitoneal en ratones normoglucémicos y con diabetes inducida con aloxana. Resultados. La administración de 300 mg/kg de los extractos clorofórmicos de P. edulis, B. terniflora y hexánico de B. veronicaefolia en ratones diabéticos disminuye el nivel de glucosa sanguínea en 43.75, 58.56 y 72.13%, respectivamente. Estos extractos (300 mg/kg, administrados en ratones normoglucémicos, reducen la glucosa sanguínea en 29.61, 33.42 y 39.84%, respectivamente. Conclusiones. Con este estudio se confirma la actividad hipoglucemiante de estas plantas usadas en la medicina tradicional para el tratamiento de la diabetes.

  9. KERAGAMAN KARAKTER MORFOLOGI PLASMA NUTFAH GANYONG (CANNA EDULIS KERR.

    Directory of Open Access Journals (Sweden)

    TINTIN SUHARTINI

    2012-11-01

    Full Text Available Morphological Characters Diversity of Canna (Canna edulis kerr. Germplasm. Edible canna (Canna edulis is the source of potentially of foodstuf. Edible canna have high carbohydrate and nutritions. The starch of edible canna could be exploited as a food materials and industry. Evaluation and characterization were needed to get informations good characters of edible canna for genetic variability to get improved edible canna varieties. Indonesian Center of Agricultural Biotechnology and Genetic Resources and Development ( BB-Biogen germplasm have two groups edible canna collection , they are red edible canna and white edible canna. The result showed the morphology characters of 27 edible canna accecions were not different on qualitative characters. Such as of 23 white edible canna have not different on qualitative characters. The red edible canna have red color on part of shoot, while in white edible canna have green color. The tuber of red edible canna have pink color and white color of white edible canna. The different are in the flower of white edible canna, there are 17 accecions have yellow color and 6 accecions have orange color. The quantitative characters of flowering, leaf length, leaf width, total leaf and leaf stalk length have low variability(cv <10 %. The character of plant hight, number of tiller per hill and tuber weight per hill have high coeficient variability with range of 14%-21%.

  10. Mycorrhization between Cistus ladanifer L. and Boletus edulis Bull is enhanced by the mycorrhiza helper bacteria Pseudomonas fluorescens Migula.

    Science.gov (United States)

    Mediavilla, Olaya; Olaizola, Jaime; Santos-del-Blanco, Luis; Oria-de-Rueda, Juan Andrés; Martín-Pinto, Pablo

    2016-02-01

    Boletus edulis Bull. is one of the most economically and gastronomically valuable fungi worldwide. Sporocarp production normally occurs when symbiotically associated with a number of tree species in stands over 40 years old, but it has also been reported in 3-year-old Cistus ladanifer L. shrubs. Efforts toward the domestication of B. edulis have thus focused on successfully generating C. ladanifer seedlings associated with B. edulis under controlled conditions. Microorganisms have an important role mediating mycorrhizal symbiosis, such as some bacteria species which enhance mycorrhiza formation (mycorrhiza helper bacteria). Thus, in this study, we explored the effect that mycorrhiza helper bacteria have on the efficiency and intensity of the ectomycorrhizal symbiosis between C. ladanifer and B. edulis. The aim of this work was to optimize an in vitro protocol for the mycorrhizal synthesis of B. edulis with C. ladanifer by testing the effects of fungal culture time and coinoculation with the helper bacteria Pseudomonas fluorescens Migula. The results confirmed successful mycorrhizal synthesis between C. ladanifer and B. edulis. Coinoculation of B. edulis with P. fluorescens doubled within-plant mycorrhization levels although it did not result in an increased number of seedlings colonized with B. edulis mycorrhizae. B. edulis mycelium culture time also increased mycorrhization levels but not the presence of mycorrhizae. These findings bring us closer to controlled B. edulis sporocarp production in plantations.

  11. Prevalence and intensity of pathologies induced by the toxic dinoflagellate, Heterocapsa circularisquama, in the Mediterranean mussel, Mytilus galloprovincialis.

    Science.gov (United States)

    Basti, Leila; Endo, Makoto; Segawa, Susumu; Shumway, Sandra E; Tanaka, Yuji; Nagai, Satoshi

    2015-06-01

    The harmful dinoflagellate, Heterocapsa circularisquama, has been causing mass mortalities of bivalve molluscs in Japan, at relatively low cell densities. Although several studies have been conducted to determine the toxicity mechanisms, the specific cause of death is still unclear. In a previous study, in our laboratory, it was shown that H. circularisquama (10(3) cells ml(-1)) caused extensive cytotoxicity in the gills of short-neck clams, Ruditapes philippinarum. In the present study, Mediterranean mussels, Mytilus galloprovincialis, were exposed to H. circularisquama at four cell densities (5, 50, 500, 10(3) cells ml(-1)), three temperatures (15, 20, and 25°C), and three exposure durations (3, 24, and 48 h), and the pathologies in nine organs (gills, labial palps, mantle, hepatopancreas, stomach, intestines, exhalant siphon, adductor muscles, and foot) were assessed. Foot, adductor muscles, and exhalent siphons of mussels were not affected; however, 16 inflammatory (hemocytic infiltration and aggregation, diapedesis, hyperplasia, hypertrophy, edema, melanization, and firbrosis) and degenerative (thrombus, thrombosed edema, cilia matting and exfoliation, epithelial desquamation, atrophy, and necrosis) pathologies were identified in the gills, labial palps, mantle, hepatopancreas, stomach, and intestines. The total prevalence and total intensity of pathology in each individual mussel, and the prevalence and intensity of pathology in each organ increased significantly with increased cell density, exposure duration, and temperature. The prevalence of pathology was the highest in gills, followed by the prevalence in labial palps, mantle, stomach, and intestines. Pathology was least prevalent in the hepatopancreas. The intensity of pathology was the highest in the gills, followed by the labial palps and mantle, the stomach and intestines, and the hepatopancreas. This detailed quantitative histopathological study demonstrates that exposure to H. circularisquama

  12. Acute effects of non-weathered and weathered crude oil and dispersant associated with the Deepwater Horizon incident on the development of marine bivalve and echinoderm larvae.

    Science.gov (United States)

    Stefansson, Emily S; Langdon, Chris J; Pargee, Suzanne M; Blunt, Susanna M; Gage, Susan J; Stubblefield, William A

    2016-08-01

    Acute toxicity tests (48-96-h duration) were conducted with larvae of 2 echinoderm species (Strongylocentrotus purpuratus and Dendraster excentricus) and 4 bivalve mollusk species (Crassostrea virginica, Crassostrea gigas, Mytilus galloprovincialis, and Mercenaria mercenaria). Developing larvae were exposed to water-accommodated fractions (WAFs) and chemically enhanced water-accommodated fractions (CEWAFs) of fresh and weathered oils collected from the Gulf of Mexico during the Deepwater Horizon incident. The WAFs (oils alone), CEWAFs (oils plus Corexit 9500A dispersant), and WAFs of Corexit alone were prepared using low-energy mixing. The WAFs of weathered oils had no effect on survival and development of echinoderm and bivalve larvae, whereas WAFs of fresh oils showed adverse effects on larval development. Similar toxicities were observed for weathered oil CEWAFs and WAFs prepared with Corexit alone for oyster (C. gigas and C. virginica) larvae, which were the most sensitive of the tested invertebrate species to Corexit. Mean 10% effective concentration values for total polycyclic aromatic hydrocarbons and dipropylene glycol n-butyl ether (a marker for Corexit) in the present study were higher than all concentrations reported in nearshore field samples collected during and after the Deepwater Horizon incident. The results suggest that water-soluble fractions of weathered oils and Corexit dispersant associated with the Deepwater Horizon incident had limited, if any, acute impacts on nearshore larvae of eastern oysters and clams, as well as other organisms with similar sensitivities to those of test species in the present study; however, exposure to sediments and long-term effects were not evaluated. Environ Toxicol Chem 2016;35:2016-2028. © 2016 SETAC.

  13. The Bivalve Yangtzedonta is not the Brachiopod Xianfengella

    Institute of Scientific and Technical Information of China (English)

    YU Wen

    2005-01-01

    The alleged "holotype" of the bivalve Yangtzedontaprimitiva Yu, 1985 figured by Qian (2001) is a broken and distorted specimen of the brachiopod Xianfengella prima He and Yang, 1982 and not the holotype of Y. primitiva. Qian contends that the oldest recognized monoplacophoran, Maikhanella pristinis (Jiang, 1980), is neither a monoplacophoran nor the oldest molluscan fossil in the Meishucunian Stage of China. Furthermore, he considers that the oldest bivalve Xianfengoconcha elliptica Zhang, 1980 is an inarticulate brachiopod, not a mollusc. Watsonella yunnanensis (He and Yang, 1982), is associated with Yangtzedonta primitiva Yu but indicates no evolutionary relationship between the Classes Rostroconchia and Bivalvia in the Lower Cambrian Zhongyicun Member of the Yuhucun Formation. Qian's confusion in using non-molluscan fossils to discuss the early evolution of shelled molluscs also confuses the basic concepts of the respective groups.

  14. Bivalves: Indicateurs de pollution microbienne des eaux littorales

    OpenAIRE

    Plusquellec, A; Beucher, M; Legal, Y

    1984-01-01

    Une étude a été réalisée en baie de Concarneau (France), dans le but de comparer la contamination de l'eau et de moules d'un même site naturel par le dénombrement des indicateurs fécaux usuels : Coliformes fécaux et Streptocoques fécaux. La concentration par les bivalves est importante, mais diffère pour les deux indicateurs bactériens. Le dénombrement des Streptocoques fécaux dans les bivalves permet d'annuler une partie des variations observées dans l'eau. L'efficacité des moules comme maté...

  15. STUDIES ON ANTIOXIDANT, ANTIHYPERGLYCEMIC AND ANTIMICROBIAL EFFECTS OF EDIBLE MUSHROOMS BOLETUS EDULIS AND CANTHARELLUS CIBARIUS

    OpenAIRE

    Daniela Elena ZAVASTIN; Alexandra BUJOR; Tuchiluş, Cristina; Cornelia Geanina MIRCEA; Simona Petronela GHERMAN; Ana Clara APROTOSOAIE; Miron, Anca

    2016-01-01

    The study evaluated the antioxidant, antihyperglycemic and antimicrobial effects of both ethanolic and hydromethanolic extracts of the fruiting bodies of wild edible mushrooms Boletus edulis (penny bun) and Cantharellus cibarius (golden chanterelle) sampled in Poiana Stampei (Suceava county, Romania). The total phenolic contents of extracts were also determined. Boletus edulis hydromethanolic extract showed the highest total phenolic content (72.78±0.29 mg/g). This extract was also the most a...

  16. Pertumbuhan dan struktur anatomi daun dua varietas ganyong (Canna edulis) pada ketersediaan air berbeda

    OpenAIRE

    OCTAVIANA RAISA DEWI; ARI PITOYO; ENDANG ANGGARWULAN

    2014-01-01

    Dewi OR, Pitoyo A, Anggarwulan E. 2013. Pertumbuhan dan struktur anatomi daun dua varietas ganyong (Canna edulis) pada ketersediaan air berbeda. Bioteknologi 11: 5-10. The aim of the research was to study the effect of different water availability on growth and anatomical structure of leaves of two varieties of canna (Canna edulis Kerr.), which are verdos varieties (white varieties) and morados varieties (red varieties). Information about physiological and anatomical character of canna is imp...

  17. Indian marine bivalves: Potential source of antiviral drugs

    Digital Repository Service at National Institute of Oceanography (India)

    Chatterji, A.; Ansari, Z.A.; Ingole, B.S.; Bichurina, M.A.; Sovetova, M.; Boikov, Y.A.

    in large quantities by traditional methods and sold live in the market for human consumption. The economically important sp e cies of marine bivalves are green mussel ( Perna viridis ), e s tuarine oyster ( Crassostrea madrasensis ), giant oyster... in developing an effecti ve drug has been the unique characteristics of antigenic variation of virus resulting in the emergence of new variant virus strains 14 . There are a number of antiviral drugs introduced in the market such as tricyclic sy m- metric...

  18. Comparative central effects of the aqueous leaf extract of two populations of Passiflora edulis

    Directory of Open Access Journals (Sweden)

    Adriana S.F.S.J. Ayres

    2015-10-01

    Full Text Available ABSTRACTPassiflora edulis Sims, Passifloraceae, has been used in Brazilian traditional folk medicine to the treatment of anxiety and insomnia. P. edulis is commonly known for its economic interests in Brazil. This species exhibits significant variability in the fruit rind color, then two subpopulations has been described (P. edulis fo. flavicarpa O. Deg. (PEF; P. edulis fo. edulis (PEE. This study compared phytochemical profile and biological actions of aqueous leaf extract of PEE and PEF. HPLC analysis showed marked distinct chromatograms to the P. edulisvarieties. However, in both extracts the major compounds observed were flavonoids C-glycosides. Behavioral studies showed that PEE (300 mg/kg, p.o. and PEF (100 and 300 mg/kg, p.o. reduced anxiety in the elevated plus maze test. PEE (300 and 1000 mg/kg, p.o. and PEF (1000 mg/kg, p.o. also induced antidepressant-like actions in the forced swimming test. PEE 1000 mg/kg significantly reduced distance moved, thus suggesting sedation. No alterations in sleeping time were observed with PEE and PEF extracts. In conclusion, despite the similarities between the biological actions observed for both P. edulis varieties, quite different phytochemical profile was herein reported. These data suggest that the anxiolytic and antidepressant actions are not due to a specific phytochemical component.

  19. Molecular and acute temperature stress response characterizations of caspase-8 gene in two mussels, Mytilus coruscus and Mytilus galloprovincialis.

    Science.gov (United States)

    Zhang, Duo; Wang, Hong-Wei; Yao, Cui-Luan

    2014-01-01

    The caspase family represents aspartate-specific cysteine proteases that play key roles in initiation of apoptosis in various cells response to environmental stress. In this study, two caspase-8 cDNA sequences were cloned from two Mytilus mussels, Mytilus coruscus (Mccaspase-8) and Mytilus galloprovincialis (Mgcaspase-8), respectively. The full-length cDNA of Mccaspase-8 was 1884bp, including a 5'-terminal untranslated region (UTR) of 140bp, a 3'-terminal UTR of 238bp and an open reading frame (ORF) of 1506bp encoding a polypeptide of 501 amino acids. The 1775bp full-length Mg caspase-8 cDNA sequence contained an ORF of 1488bp encoding a polypeptide of 495 amino acid residues, a 5'-UTR of 51bp and a 3'-UTR of 236bp. Both the Mccaspase-8 and Mgcaspase-8 amino acid sequences contained two highly conservative death effector domains (DEDs) at N-terminal, the caspase family domains P20 and P10 and the caspase family cysteine active site 'KPKLFFIQACQG'. Phylogenetic analysis revealed that Mccaspase-8 and Mgcaspase-8 were clustered with the caspase-8 from other organisms, with the close relationship with caspase-8 from mollusk. Quantitative real-time reverse transcription PCR (qRT-PCR) analysis indicated that the predominant transcripts of Mccaspase-8 were in mantle and gonad tissue of M. coruscus and the high expression levels of Mgcaspase-8 were in digestive gland and gill tissue of M. galloprovincialis, respectively. The impacts of temperature stress on Mccaspase-8 and Mgcaspase-8 expressions were tested in gill tissue and hemocytes of both species. Our results showed that both Mccaspase-8 and Mgcaspase-8 transcripts and caspase-8 activity in gill tissue and hemocytes could be induced significantly after cold and heat stress (pgalloprovincialis.

  20. Comparative study of immune responses in the deep-sea hydrothermal vent mussel Bathymodiolus azoricus and the shallow-water mussel Mytilus galloprovincialis challenged with Vibrio bacteria.

    Science.gov (United States)

    Martins, Eva; Figueras, António; Novoa, Beatriz; Santos, Ricardo Serrão; Moreira, Rebeca; Bettencourt, Raul

    2014-10-01

    The deep-sea hydrothermal vent mussel Bathymodiolus azoricus and the continental European coast Mytilus galloprovincialis are two bivalves species living in highly distinct marine habitats. Mussels are filter-feeding animals that may accumulate rapidly bacteria from the environment. Contact with microorganism is thus inevitable during feeding processes where gill tissues assume a strategic importance at the interface between the external milieu and the internal body cavities promoting interactions with potential pathogens during normal filtration and a constant challenge to their immune system. In the present study B. azoricus and M. galloprovincialis were exposed to Vibrio alginolyticus, Vibrio anguillarum and Vibrio splendidus suspensions and to a mixture of these Vibrio suspensions, in order to ascertain the expression level of immune genes in gill samples, from both mussel species. The immune gene expressions were analyzed by means of quantitative-Polymerase Chain Reaction (qPCR). The gene expression results revealed that these bivalve species exhibit significant expression differences between 12 h and 24 h post-challenge times, and between the Vibrio strains used. V. splendidus induced the strongest gene expression level in the two bivalve species whereas the NF-κB and Aggrecan were the most significantly differentially expressed between the two mussel species. When comparing exposure times, both B. azoricus and M. galloprovincialis showed similar percentage of up-regulated genes at 12 h while a marked increased of gene expression was observed at 24 h for the majority of the immune genes in M. galloprovincialis. This contrasts with B. azoricus where the majority of the immune genes were down-regulated at 24 h. The 24 h post-challenge gene expression results clearly bring new evidence supporting time-dependent transcriptional activities resembling acute phase-like responses and different immune responses build-up in these two mussel species when challenged

  1. In Vitro Analysis of Early Genotoxic and Cytotoxic Effects of Okadaic Acid in Different Cell Types of the Mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Laffon, Blanca; Eirín-López, José M; Méndez, Josefina

    2015-01-01

    Okadaic acid (OA) is the predominant biotoxin responsible for diarrhetic shellfish poisoning (DSP) syndrome in humans. While its harmful effects have been extensively studied in mammalian cell lines, the impact on marine organisms routinely exposed to OA is still not fully known. Few investigations available on bivalve molluscs suggest less genotoxic and cytotoxic effects of OA at high concentrations during long exposure times. In contrast, no apparent information is available on how sublethal concentrations of OA affect these organisms over short exposure times. In order to fill this gap, this study addressed for the first time in vitro analysis of early genotoxic and cytotoxic effects attributed to OA in two cell types of the mussel Mytilus galloprovincialis. Accordingly, hemocytes and gill cells were exposed to low OA concentrations (10, 50, 100, 200, or 500 nM) for short periods of time (1 or 2 h). The resulting DNA damage, as apoptosis and necrosis, was subsequently quantified using the comet assay and flow cytometry, respectively. Data demonstrated that (1) mussel hemocytes seem to display a resistance mechanism against early genotoxic and cytotoxic OA-induced effects, (2) mussel gill cells display higher sensitivity to early OA-mediated genotoxicity than hemocytes, and (3) mussel gill cells constitute more suitable systems to evaluate the genotoxic effect of low OA concentrations in short exposure studies. Taken together, this investigation provides evidence supporting the more reliable suitability of mussel gill cells compared to hemocytes to evaluate the genotoxic effect of low short-duration exposure to OA.

  2. Mitochondrial DNA transcription levels during spermatogenesis and early development in doubly uniparental inheritance of the mitochondrial DNA system of the blue mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Sano, Natsumi; Obata, Mayu; Komaru, Akira

    2013-08-01

    In some species of bivalve, there are two highly diverged mitochondrial genomes, one found in all individuals (F type) and the other normally in males only (M type). In Mytilus, a maternally-dependent sex ratio of the progeny has been reported. Some females almost exclusively produce daughters, while others produce a high proportion of sons. We previously reported that in M. galloprovincialis, M type mtDNA copy number may be maintained during spermatogenesis and the development of larvae of male-biased mothers to sustain the doubly uniparental inheritance system. In this study, we investigated transcription levels of M type mtDNA before and after fertilization to understand its function in the germ line. First, we quantified transcription levels of M type mtDNA in testicular cells dissected using laser-capture micro-dissection. The transcription levels of M type mtDNA were not significantly different between spermatogonia and spermatocytes versus spermatids and spermatozoa. Next, we examined differences in transcription levels of M type mtDNA between larvae from male-biased and female-biased mothers. The transcription levels of M type mtDNA significantly increased 24 and 48 h after fertilization in male-biased crosses. By contrast, transcription levels significantly decreased in female-biased crosses. These results suggest M type mtDNA may play a role in early germ line formation.

  3. Application of monoclonal antibody against granulocytes of scallop Chlamys farreri on granulocytes occurrence at different developmental stages and antigenic cross-reactivity of granulocytes in five other bivalve species.

    Science.gov (United States)

    Xing, Jing; Tang, Xiaoqian; Ni, Yongqing; Zhan, Wenbin

    2014-01-01

    A monoclonal antibody (MAb) 6H7 raised specifically against granulocytes of scallop (Chlamys farreri) was employed to observe granulocyte occurrence successively in blastulae, gastrulae, trochophore larvae, D-shape larvae, umbo-veliger larvae and creeping larvae of C. farreri by immunohistochemistry assay contrasted with H&E stain using semi-thin sections. Moreover, the reactivity of the MAb with granulocytes of C. farreri, Bay scallop Argopecten irradians, Japanese scallop Patinopecten yessoensis, Blue mussel Mytilus edulis, Pacific oyster Crassostrea gigas and Manila clam Ruditapes philippinarum, was detected by immunofluorescence assay (IFA) with differential interference contrast and fluorescent microscopy and flow cytometric immunofluorescence assay (FCIFA). The results showed that positive signals were first observed at D-shape larval stage, about 28 h post fertilization, after that, umbo-veliger larvae exhibited the positive cells with a diameter of 3-5 μm distributed in velum, digestive gland and esophagus. Then in creeping larvae, the number of positive cells increased with average diameter of 5-7 μm, and widely distributed in foot, digestive gland, gills and adductor muscles. No positive signal was found in blastulae, gastrulae and trochophore larvae. The results of IFA and FCIFA showed MAb 6H7 reacted to granulocytes of C. farreri, A. irradians, P. yessoensis and C. gigas, and the positive percentage reactivity were 53 ± 2.5%, 15 ± 2.5%, 12 ± 2.1% and 19 ± 2.1%, respectively, however, no cross-reaction was detected in hemocytes of R. philippinarum and M. edulis.

  4. 化学物质诱导变态后紫贻贝稚贝的生长及存活%Growth and survival of the mussel Mytilus galloprovincialis post-larvae metamorphosed using different chemical compounds as inducers

    Institute of Scientific and Technical Information of China (English)

    杨金龙; 李一峰; 沈和定; SATUITO Glenn Cyril; KITAMUTRA Hitoshi

    2009-01-01

    在以往实验的基础上,跟踪调查了筛选出的化学诱导物质对紫贻贝(Mytilus edulis)幼虫变态后的生长和成活率的影响,并比较了其与相同条件下自然诱导物、微生物膜诱导后的稚贝的生长和成活率.实验结果表明,肾上腺素、苯肾上腺素、可乐宁、KCI和NH_4Cl 5种化学物质均成功地诱导了该种幼虫的变态,其变态后稚贝同微生物诱导变态后的稚贝以相同的速度生长,且在培育过程中无死亡稚贝出现.因此,这些化学物质可作为该种养殖以及海洋防污染研究中幼虫变态的有效人工诱导物.%The growth and survival of Mytilus galloprovincialis post-larvae metamorphosed using different chemical compounds were investigated in this study to identify potential inducers in aquaculture and anti-fouling and biofouling researches. All tested chemical compounds including epinephrine, phenylephrine, clonidine, KCl and NH_4 Cl induced larvae to metamorphose, and post-larvae metamorphosed using these compounds survived as juveniles and grew at the same rate as those from microbial biofilms. These chemical compounds, therefore, can be used as effective inducers of larval metamorphosis in aquaculture and antifoul-ing and biofouling studies using juveniles.

  5. Source and impact of lead contamination on {delta}-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

    Energy Technology Data Exchange (ETDEWEB)

    Company, R.; Serafim, A.; Lopes, B.; Cravo, A. [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Kalman, J.; Riba, I.; DelValls, T.A. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Blasco, J. [Instituto Ciencias Marinas Andalucia (CSIC), Campus Rio San Pedro, 11510 Puerto Real, Cadiz (Spain); Delgado, J. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Sarmiento, A.M. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Nieto, J.M. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Shepherd, T.J.; Nowell, G. [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Bebianno, M.J., E-mail: mbebian@ualg.pt [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2011-01-17

    Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme ({delta}-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ({sup 206}Pb/{sup 204}Pb, {sup 207}Pb/{sup 204}Pb and {sup 208}Pb/{sup 204}Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 {+-} 1.09 {mu}g g{sup -1} Pb d.w.) and D. trunculus (1.95 {+-} 0.10 {mu}g g{sup -1} Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels (<0.38 {mu}g g{sup -1} Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e{sup -8.3[Pb]}; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in

  6. Effect of dietary polyunsaturated fatty acids on reproductive output and larval growth of bivalves

    NARCIS (Netherlands)

    Hendriks, I.E.; Van Duren, L.A.; Herman, P.M.J.

    2003-01-01

    The pre-spawning condition of adult bivalves is influenced by quantity and quality of available food. For bivalves, the essential polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) 20:5(n-3) and docosahexaenoic acid (DHA) 22:6(n-3) are presumed to determine the nutritional value of alga

  7. Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India

    Indian Academy of Sciences (India)

    R P Kachhara; R L Jodhawat; K Bigyapati Devi

    2012-04-01

    Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions – the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina (Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten (Amussiopecten) labadyei d’Archiac and Haime, Periglypta puerpera (Linne’) var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23° 50′N; 68

  8. Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India

    Science.gov (United States)

    Kachhara, R. P.; Jodhawat, R. L.; Devi, K. Bigyapati

    2012-04-01

    Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions - the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina ( Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten ( Amussiopecten) labadyei d'Archiac and Haime, Periglypta puerpera (Linne') var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23°50'N; 68°47'E

  9. Indigenous multiplication and production practices of the tuber crop Plectranthus edulis in Chencha and Wolaita, Southern Ethiopia

    NARCIS (Netherlands)

    Taye, M.; Lommen, W.J.M.; Struik, P.C.

    2007-01-01

    Plectranthus edulis (syn. Coleus edulis) is a tuber-bearing labiate species cultivated in parts of southern Ethiopia. To learn about traditional cultural practices and their rationale, a survey was conducted among farmers from Chencha and Wolaita experienced in growing this crop. A pre-tested questi

  10. Intra-population variability of ocean acidification impacts on the physiology of Baltic blue mussels (Mytilus edulis): integrating tissue and organism response.

    Science.gov (United States)

    Stapp, L S; Thomsen, J; Schade, H; Bock, C; Melzner, F; Pörtner, H O; Lannig, G

    2016-12-05

    Increased maintenance costs at cellular, and consequently organism level, are thought to be involved in shaping the sensitivity of marine calcifiers to ocean acidification (OA). Yet, knowledge of the capacity of marine calcifiers to undergo metabolic adaptation is sparse. In Kiel Fjord, blue mussels thrive despite periodically high seawater PCO2, making this population interesting for studying metabolic adaptation under OA. Consequently, we conducted a multi-generation experiment and compared physiological responses of F1 mussels from 'tolerant' and 'sensitive' families exposed to OA for 1 year. Family classifications were based on larval survival; tolerant families settled at all PCO2 levels (700, 1120, 2400 µatm) while sensitive families did not settle at the highest PCO2 (≥99.8% mortality). We found similar filtration rates between family types at the control and intermediate PCO2 level. However, at 2400 µatm, filtration and metabolic scope of gill tissue decreased in tolerant families, indicating functional limitations at the tissue level. Routine metabolic rates (RMR) and summed tissue respiration (gill and outer mantle tissue) of tolerant families were increased at intermediate PCO2, indicating elevated cellular homeostatic costs in various tissues. By contrast, OA did not affect tissue and routine metabolism of sensitive families. However, tolerant mussels were characterised by lower RMR at control PCO2 than sensitive families, which had variable RMR. This might provide the energetic scope to cover increased energetic demands under OA, highlighting the importance of analysing intra-population variability. The mechanisms shaping such difference in RMR and scope, and thus species' adaptation potential, remain to be identified.

  11. Trematod-inficeret reduktion i byssus produktion øger blåmuslingers (Mytilus edulis) mortalitet på grund af predation fra strandkrabber

    DEFF Research Database (Denmark)

    Karin Svane, Bech; Mouritsen, Kim Nørgaard

    fod, hvilket kan påvirke antallet af afsatte byssus tråde og dermed muslingens fasthæftningsstyrke. To feltforsøg i Limfjorden bekræftede, at infektion med H. elongata reducerer antallet af afsatte byssus tråde mens diameteren på trådene øges. Dette antyder, at muslingens evne til at producere byssus...... matrix ikke nedsættes betydeligt som følge af trematod infektionen men at reduktionen i antallet af byssus tråde måske skyldes en mekanisk funktionsfejl i foden. Det reducerede antal byssus tråde betyder, at inficerede muslingerne ikke er så sikkert fasthæftet til deres substrat og et forsøg viste...

  12. Source of error in the chromatographic study of /sup 35/S-sulfate labeled mucous glycoproteins secreted by the gill epithelium of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Sabouni, A.H.; Ma, J.K.; Malanga, C.J.

    1986-01-01

    HPLC combined with (/sup 35/S)-sulfate/(/sup 3/H)-glucosamine radiolabeling were employed to study the synthesis and secretion of mucous glycoproteins. The secreted radiolabeled glycoproteins were separated from the medium by precipitation with a mixture of trichloroacetic-phosphotungstic acids (TCA/PTA). The redissolved glycoproteins were chromatographed on an anion exchange protein column at varying pH of the mobile phase and fractions were collected for liquid scintillation counting. Varying the pH of the mobile phase from pH 3 to 7 resulted in a decrease of glycoprotein bound (/sup 35/S) from 69.5 to 0.5% of the total recovered (/sup 35/S)-sulfate with the remainder recovered as free (/sup 35/S)-sulfate. The (/sup 3/H)-labeled glycoprotein recovered under the uV peaks at this pH range was 99.5%. When high performance size exclusion chromatography was performed the change in mobile phase pH did not affect the 100% recovery of either (/sup 35/S)-or (/sup 3/H)-labels under the uV peaks. No free (/sup 35/S)-sulfate was obtained when (/sup 35/S)-labeled glycoproteins were separated from the medium using dialysis. These data suggest that the standard method of TCA/PTA precipitation of (/sup 35/S)-labeled glycoproteins may cleave the (/sup 35/S)-sulfate ester linkages to the oligosaccharide chains. The (/sup 35/S)-sulfate may then rebind to the macromolecule by a relatively strong noncovalent bond. This may prove critical in anion exchange protein HPLC studies.

  13. High performance liquid chromatography (HPLC) study of (/sup 35/S)- and (/sup 3/H)-labeled mucus glycoproteins secreted by the isolated mucociliated gill epithelium of Mytilus edulis

    Energy Technology Data Exchange (ETDEWEB)

    Sabouni, A.; Ma, J.K.; Malanga, C.J.

    1986-03-05

    HPLC combined with (/sup 35/S)-sulfate/(/sup 3/H)-glucosamine radiolabeling were employed to study the synthesis and secretion of mucous glycoproteins. The radiolabeled secreted glycoproteins were separated from the medium by precipitation with a mixture of trichloroacetic-phosphotungstic acids (TCA/PTA). The redissolved glycoproteins were chromatographed on an anion exchange protein column at varying pH of the mobile phase and fractions were collected for liquid scintillation counting. Varying the pH of the mobile phase from pH 3 to 7 resulted in a decrease of glycoprotein bound (/sup 35/S) from 69.5 to 0.5% of the total recovered (/sup 35/S)-sulfate with the remainder recovered as free (/sup 35/S)-sulfate. The (/sup 3/H)-labeled glycoprotein recovered under the uV peaks at this pH range was 99.5%. When high performance size exclusion chromatography was performed the change in mobile phase pH did not affect the 100% recovery of either (/sup 35/S)- or (/sup 3/H)-labels under the uV peaks. No free (/sup 35/S)-sulfate was obtained when (/sup 35/S)-labeled glycoproteins were separated form the medium using dialysis. These data suggest that the standard method of TCA/PTA precipitation of (/sup 35/S)-labeled glycoproteins may cleave the (/sup 35/S)-sulfate ester linkages to the oligosaccharide chains. The (/sup 35/S)-sulfate may then rebind to the macromolecule by a relatively strong noncovalent bond. This may prove critical in anion exchange protein HPLC studies.

  14. Seagrass beds as ocean acidification refuges for mussels? High resolution measurements of pCO2 and O2 in a Zostera marina and Mytilus edulis mosaic habitat

    Directory of Open Access Journals (Sweden)

    V. Saderne

    2015-07-01

    Full Text Available It has been speculated that macrophytes beds might act as a refuge for calcifiers from ocean acidification. In the shallow nearshores of the western Kiel Bay (Baltic Sea, mussel and seagrass beds are interlacing, forming a mosaic habitat. Naturally, the diverse physiological activities of seagrasses and mussels are affected by seawater carbonate chemistry and they locally modify it in return. Calcification by shellfishes is sensitive to seawater acidity; therefore the photosynthetic activity of seagrasses in confined shallow waters creates favorable chemical conditions to calcification at daytime but turn the habitat less favorable or even corrosive to shells at night. In contrast, mussel respiration releases CO2, turning the environment more favorable for photosynthesis by adjacent seagrasses. At the end of summer, these dynamics are altered by the invasion of high pCO2/low O2 coming from the deep water of the Bay. However, it is in summer that mussel spats settle on the leaves of seagrasses until migrating to the permanent habitat where they will grow adult. These early life phases (larvae/spats are considered as most sensitive with regard to seawater acidity. So far, the dynamics of CO2 have never been continuously measured during this key period of the year, mostly due to the technological limitations. In this project we used a combination of state-of-the-art technologies and discrete sampling to obtain high-resolution time-series of pCO2 and O2 at the interface between a seagrass and a mussel patch in Kiel Bay in August and September 2013. From these, we derive the entire carbonate chemistry using statistical models. We found the monthly average pCO2 more than 50 % (approx. 640 μatm for August and September above atmospheric equilibrium right above the mussel patch together with large diel variations of pCO2 within 24 h: 887 ± 331 μatm in August and 742 ± 281 μatm in September (mean ± SD. We observed important daily corrosiveness for calcium carbonates (Ωarag and Ωcalc < 1 centered on sunrise. On the positive side, the investigated habitat never suffered from hypoxia during the study period. We emphasize the need for more experiments on the impact of these acidic conditions on (juvenile mussels with a focus on the distinct day-night variations observed.

  15. Effects of various pollutant mixtures on immune responses of the blue mussel (Mytilus edulis) collected at a salinity gradient in the Danish belt

    DEFF Research Database (Denmark)

    Höher, N.; Köhler, A.; Strand, Jakob

    The Baltic Sea is a unique semi-enclosed sea with a steady salinity gradient (5‰ to 30‰). Organisms have adapted to such low salinities, but are suspected to be more susceptible to stress. Within the frame of the integrated environmental monitoring BONUS+ project “BEAST” (Biological Effects...... of Anthropogenic Chemical Stress) the applicability of immune responses as salinity independent biomarkers for toxic effects in the blue mussel was investigated at 5 stations in the Danish Belt Sea (Baltic Sea) in autumn 2009. These stations were characterised by a salinity range (10.9 to 18.8‰) and different...

  16. Dredging of blue mussels ( Mytilus edulis L.) in a Danish sound: stock sizes and fishery-effects on mussel population dynamic

    DEFF Research Database (Denmark)

    Dolmer, Per; Kristensen, Per Sand; Hoffmann, Erik

    1999-01-01

    in the mussel stock. In summer 1994, there was a long period of oxygen depletion in parts of Limfjorden. This caused mortality of 33% of the mussels in the affected areas. In fishery zones without oxygen depletion a 46% increase in the mussel stocks was estimated. The massive loss of blue mussels caused...

  17. Growth-Prediction Model for Blue Mussels (Mytilus edulis) on Future Optimally Thinned Farm-Ropes in Great Belt (Denmark)

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgård, Hans

    2016-01-01

    20). Similar results were obtained by use of the ad hoc BEG model which also demonstrated the sensitivity of growth prediction to levels of chl a concentration, but less to temperature. The results suggest that it is possible (when the conditions are optimal, i.e., no intraspecific competition...... competition may deviate from the potential (optimal) growth under specified chl a and temperature conditions, and this implies that the effect of thinning to optimize the individual growth by eliminating intraspecific competition can be rationally evaluated....

  18. Pollution from mining in South Greenland: Uptake and release of Pb by blue mussels (Mytilus edulis L.) documented by transplantation experiments

    DEFF Research Database (Denmark)

    Zimmer, L.A.; Asmund, G.; Johansen, P.;

    2011-01-01

    the same level as the resident population 12–16 months following transplantation. Mussels transplanted from the polluted mining site at Ivittuut to the pristine Kugnait Bay depurated only 7–21% of their original Pb content, and the release was within the first 10 days following transplantation, after which...... spectrometry (flame AAS) and graphite furnace atomic absorption spectrometry (graphite furnace AAS). Uptake and release of Pb were documented to be slow processes. For mussels transplanted from the pristine Kugnait Bay to the polluted mining site at Ivittuut, a continuous accumulation throughout...

  19. Seagrass beds as ocean acidification refuges for mussels? High resolution measurements of pCO2 and O2 in a Zostera marina and Mytilus edulis mosaic habitat

    Science.gov (United States)

    Saderne, V.; Fietzek, P.; Aßmann, S.; Körtzinger, A.; Hiebenthal, C.

    2015-07-01

    It has been speculated that macrophytes beds might act as a refuge for calcifiers from ocean acidification. In the shallow nearshores of the western Kiel Bay (Baltic Sea), mussel and seagrass beds are interlacing, forming a mosaic habitat. Naturally, the diverse physiological activities of seagrasses and mussels are affected by seawater carbonate chemistry and they locally modify it in return. Calcification by shellfishes is sensitive to seawater acidity; therefore the photosynthetic activity of seagrasses in confined shallow waters creates favorable chemical conditions to calcification at daytime but turn the habitat less favorable or even corrosive to shells at night. In contrast, mussel respiration releases CO2, turning the environment more favorable for photosynthesis by adjacent seagrasses. At the end of summer, these dynamics are altered by the invasion of high pCO2/low O2 coming from the deep water of the Bay. However, it is in summer that mussel spats settle on the leaves of seagrasses until migrating to the permanent habitat where they will grow adult. These early life phases (larvae/spats) are considered as most sensitive with regard to seawater acidity. So far, the dynamics of CO2 have never been continuously measured during this key period of the year, mostly due to the technological limitations. In this project we used a combination of state-of-the-art technologies and discrete sampling to obtain high-resolution time-series of pCO2 and O2 at the interface between a seagrass and a mussel patch in Kiel Bay in August and September 2013. From these, we derive the entire carbonate chemistry using statistical models. We found the monthly average pCO2 more than 50 % (approx. 640 μatm for August and September) above atmospheric equilibrium right above the mussel patch together with large diel variations of pCO2 within 24 h: 887 ± 331 μatm in August and 742 ± 281 μatm in September (mean ± SD). We observed important daily corrosiveness for calcium carbonates (Ωarag and Ωcalc < 1) centered on sunrise. On the positive side, the investigated habitat never suffered from hypoxia during the study period. We emphasize the need for more experiments on the impact of these acidic conditions on (juvenile) mussels with a focus on the distinct day-night variations observed.

  20. Relation between the concentration of Dinophysis acuminata and diarrheic shellfish poisoning toxins in blue mussels (Mytilus edulis) during a toxic episode in the Limfjord (Denmark), 2006

    DEFF Research Database (Denmark)

    Jørgensen, Kevin; Andersen, Per

    2008-01-01

    were observed. The maximum concentration level of approximately 600-700 mu g OA equivalents kg(-1) was reached at approximately 5,000 cells1(-1) of D. acuminata. A further increase in the concentration of D. acuminata did not lead to any further increase in the concentration of OA in the blue mussels...... equivalents in the raw blue mussels was 706 mu g/kg. Single cell toxicity measurements showed a mean content of 31 pg OA cell(-1) (min 19; max 72 pg OA cell(-1)). The impact of the concentration procedure was investigated using a range of volumes filtered from 0,21-101 filter(-1). Toxins were lost during...

  1. 生产性加工及采集贻贝(Mytilus edulis L.)卵的方法

    Institute of Scientific and Technical Information of China (English)

    严隽箕

    1985-01-01

    在对虾工厂化育苗中,饵料培养,特别是动物性饵料轮虫的生产性培养,目前尚有一定的困难。一般来说,因为需要一定规模的培养设备和条件,同时,尚需一定的培养方法与技术。因此,目前大部分生产单位在对虾人工育苗中所使用的活体动物性饵料主要以卤虫(Artemia salina)无节幼体为主,

  2. Efficiency of blue mussel (Mytilus edulis) spat collectors in highly dynamic tidal environments of the Lower Saxonian coast (southern North Sea).

    Science.gov (United States)

    Walter, Uwe; Liebezeit, Gerd

    2003-07-01

    Traditional mussel culture in the Wadden Sea, southern North Sea, is carried out by taking seed mussels of about 1-4 cm shell length from natural beds and transplanting them to permanently water covered sites. Besides the damage done to the natural beds, the ratio of seeded to harvested mussels is only about 1:1-1.3, i.e. about the same tonnage of mussels seeded is recovered. In addition, this technique relies exclusively on natural spat falls, which do not occur regularly. In order to overcome these difficulties spat collectors have been deployed in the Jade Bay, southern North Sea. These provided suitable settlement grounds for mussel larvae. Blue mussel weights reached weights of about 8-9 kg/m collector rope with maximum shell lengths of 4-5 cm within one growing season.

  3. DNA damage, acetylcholinesterase activity and lysosomal stability in native and transplanted mussels (Mytilus edulis) in areas close to coastal chemical dumping sites in Denmark

    DEFF Research Database (Denmark)

    Rank, Jette; Lehtonen, Kari K.; Strand, Jakob

    2007-01-01

    potentially affected by anthropogenic pollution originating from chemical dumping sites. The results indicate responses to pollution in all the biomarkers applied at the suspected areas, but the results were not consistent. Seasonal fluctuations in exposure situations at the study sites make interpretation...

  4. Laboratory Evaluation of Adenylate Energy Charge as a Test for Stress in Mytilus edulis and Nephtys incisa Treated with Dredged Material.

    Science.gov (United States)

    1985-02-01

    concentrations of three adenine nucleotides, adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP), which are...that all trace metals but iron were eliminated and the concentration of the vitamins thiamin and B12 were doubled. Adenylate Extraction 13. The adductor

  5. THE AVAILABILITY OF Mytilus galloprovincialis FOR MONITORING ENTERIC BACTERIA

    Directory of Open Access Journals (Sweden)

    Nüket SĐVRĐ

    2012-01-01

    Full Text Available In this study, the usage of Mediterranean Mussel (Mytilus galloprovincialis Lamarck, 1819 as monitoring organism on enteric bacteria concentrations in heavily polluted marine environments and its use possibilities as water quality improving tool were investigated. The ability of the Mediterranean Mussel to accumulate and purge fecal coliform bacteria investigated in laboratory experiments. First, increase on bacteria concentration was observed on 1,5th hour and sharp decrease rate lasted until 10th hours after that period slow but steady declining bacteria concentration rate was observed and beginning bacteria concentration rate was reached within next 30- 50 hours. Time dependent bacteria concentration reduction has found statistically significant at p<0.001 (r-sq = 0.81. The investigation has also revealed that mussel farming could be established in the over polluted area which is the case only in the different discharge points in the sea.

  6. Plinia edulis - leaf architecture and scanning electron micrographs

    Directory of Open Access Journals (Sweden)

    Ana M. Donato

    2013-06-01

    Full Text Available Many species of Myrtaceae, including Plinia edulis (Vell. Sobral (cambucá, have pharmacological properties and are used as hypoglycemiants and therapeutic agents against stomach problems and throat infections. Samples were collected from Tijuca Forest in Rio de Janeiro, and the morpho-anatomical data were compared with other specimens obtained from Trindade, Paraty, found in the literature. Variations in leaf anatomy were observed, and the possible causes for these effects are discussed. The plant material collected from Tijuca Forest was analyzed using scanning electron and optical microscopy. Histochemical tests were applied to identify starch, lipids, phenolic compounds and lignin. The epidermal cells exhibit straight or slightly sinuous anticlinal walls covered by a smooth cuticle with granules of wax. Simple trichomes are restricted to the midrib region, and paracytic stomata are only observed on the abaxial leaf surface. The mesophyll is dorsiventral, with conspicuous intercellular spaces in the spongy parenchyma. Intercalated columns of crystalliferous cells and subepidermal secretory cavities are observed in the single layer of palisade parenchyma. The samples obtained from Trindade, Paraty, show larger leaves, anomocytic stomata and trichomes scattered throughout the leaf surface. This plasticity might reflect leaf adaptations to environmental factors or different stages of leaf development.

  7. Development of Polymorphic Microsatellite Markers for Phyllostachys edulis (Poaceae, an Important Bamboo Species in China

    Directory of Open Access Journals (Sweden)

    Wei-Xin Jiang

    2013-06-01

    Full Text Available Premise of the study: Polymorphic microsatellite markers were developed for Phyllostachys edulis (Poaceae, an ecologically and economically important bamboo species in China, to evaluate the genetic diversity and population genetic structure of P. edulis and other Phyllostachys species. Methods and Results: Twenty microsatellite markers were developed and their polymorphisms were tested on 71 samples from three geographically disparate populations. Each locus exhibited between two and 10 alleles with an average of five alleles. Excluding monomorphic loci, observed and expected heterozygosity ranged from zero to one and from 0.041 to 0.676, respectively. Conclusions: These 20 polymorphic microsatellite loci will be useful for studies on the molecular ecology, population genetics, and conservation of P. edulis.

  8. Soluble dietary fiber from Canna edulis Ker by-product and its physicochemical properties.

    Science.gov (United States)

    Zhang, Juan; Wang, Zheng-Wu

    2013-01-30

    Using Canna edulis Ker by-product as raw materials, soluble dietary fiber (SDF) was prepared using six different methods, including chemical, physical-chemical, enzymatic, physical-enzymatic, chemical-enzymatic and physical-chemical-enzymatic methods. As main component in the C. edulis by-product composed of cellulose, glucose converts to other single sugars, which form a series of compounds in the SDF. The treated methods have impact effects on single sugar composition, metal ion content, molecular size distribution, chemical bonds and groups in the structure, thermal property and color of the final product. In view of security, high yield and homogeneity as well as good thermal stability of final product, physical-enzymatic method will be a best choice for the production of SDF from C. edulis by-product. The SDF obtained can be used as dietary supplement and additive in the food industry.

  9. Short-term feeding response of the mussel Mytilus chilensis exposed to diets containing the toxic dinoflagellate Alexandrium catenella Respuesta alimentaria inicial del bivalvo Mytilus chilensis expuesto a dietas conteniendo el dinoflagelado tóxico Alexandrium catenella

    Directory of Open Access Journals (Sweden)

    JORGE M NAVARRO

    2008-03-01

    Full Text Available The short-term feeding response of the bivalve Mytilus chilensis was measured using four diets containing different proportions of the toxic dinoflagellate Alexandrium catenella. The diets containing the highest concentrations of the dinoflagellate showed the greatest effect on the feeding activity in the mussel, with clearance and ingestión rates significantly reduced during the first hours of exposure. After this period, M. chilensis demonstrated a capacity to acclimate to the toxic diets, with feeding parameters reaching values similar to those of untreated control organisms. It was not clear if the negative effect on the feeding behavior was caused by the presence of the paralytic toxin, or due to the larger size of the dinoflagellate cells in comparison with cells of Isochrysis galbana used in the control diet. However, parallel studies with diets containing the nontoxic dinoflagellate Alexandrium affine of similar size and shape to that of A. catenella, suggested the cell size was the main cause for impairment of feeding behavior. The capacity for acclimation to either toxin or cell size by M. chilensis makes it a good indicator species for the early detection of harmful PSP events, since its relative insensitivity to the toxin allows it to quickly recover normal feeding behavior and permits it to accumulate PSP in its tissues in a short timeLa respuesta inicial del bivalvo Mytilus chilensis fue medida bajo cuatro dietas que contenían diferentes proporciones del dinoflagelado tóxico Alexandrium catenella. Las dietas que contenían las concentraciones más altas de este dinoflagelado mostraron el mayor efecto durante las primeras horas de exposición. Después de este periodo inicial, M. chilensis demostró la capacidad para aclimatarse a estas dietas tóxicas, con parámetros de alimentación que alcanzaron valores similares a aquellos de los organismos controles. No fue claro si el efecto negativo sobre la conducta de alimentación fue

  10. Heavy metal complexation in polluted molluscs. II. Oysters (Ostrea edulis and Crassostrea gigas)

    Energy Technology Data Exchange (ETDEWEB)

    Howard, A.G.; Nickless, G.

    1977-06-01

    Cadmium, zinc and copper, accumulated from polluted habitats by the oysters Ostrea edulis and Crassostrea gigas, were studued. Three distinct low molecular weight (less than 3000 daltons) zinc complexes were separated from highly contaminated C. gigas, one of which may be a complex with the amino acid taurine. Only one of these zinc complexes was present in less contaminatd specimens of O. edulis. On gel permeation chromatography of oyster extracts, copper was eluted together with amino acids (principally taurine) and the betaine homarine. No evidence of metallothionein type proteins was found.

  11. Identification and antioxidant activity of several flavonoids of Inga edulis leaves

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Jesus N.S.; Silva, Evaldo M.; Larondelle, Yvan [Universite Catholique de Louvain et Institut des Sciences de la Vie, Croix du Sud, Louvain-la-Neuve (Belgium). Unite de Biochimie de la Nutrition; Silva, Milton N. da; Arruda, Mara S.P. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Faculdade de Quimica; Rogez, Herve [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Faculdade de Engenharia de Alimentos]. E-mail: frutas@ufpa.br

    2007-07-01

    A methanol-water extract of Inga edulis leaves was fractionated to identify the polyphenolic compounds. The identified compounds were gallic acid, catechin, epicatechin, myricetin-3-rhamnopyranoside, quercetin-3-glucopyranoside and quercetin-3-rhamnopyranoside. The antioxidant activity of the extract and of pure polyphenols was measured by the ORAC assay and compared with the Total Phenolic (TP) content. The dry crude extract presented very high values for ORAC (11.16 mmol TE per g) and TP (496.5 mg GAE per g). The identified compounds were responsible for 9.53 % and 12.10 % of the ORAC value and TP content of the Inga edulis leaf extract, respectively. (author)

  12. The cloning and expression of M7 lysin in Mytilus coruscus%厚壳贻贝M7lysin分子的克隆与表达

    Institute of Scientific and Technical Information of China (English)

    刘慧慧; 薛超波; 常抗美; 杨刚

    2011-01-01

    M7 lysin is located in the mussel sperm acrosome. As an important protein for fertilization,it can dissolve vitelline membrane and determine the specificity of sperm-egg recognition of mussel. At present, the M7 lysin sequences of Mytilus edulis Linnaeus,M. Galloprovincialis and M. Trossulus have been recognized, but it hasn' t been reported in M. Coruscus. In this study, we cloned M7 lysin of At. Coruscus with homology cloning method,and it was expressed in E. Coli Rosseta( DE3). The results showed that the amplified product was about 540 bp fragment. The further sequencing revealed that the cDNA of open reading frame was 543 bp, and it had high similarity with those of M. Edulis, M. Galloprovincialis and M. Trossulus. The protein included 180 amino acids through online translation,its molecular weight was 20 ku,and its isoelectric point was 8.48. The phylogenetic tree from the amino acid sequence of M7 lysin showed that M. Edulis and M. Galloprovincialis had closest relationship, followed by M. Trossulus, and finally M. Coruscus. The results suggested that M7 lysin could be used as molecular markers to study mussel' s evolution. The protein of 25 ku was showed in SDS-PAGE when M7 lysin was expressed in the prokaryotes, which included the amino acid sequences in vector. This band was consistent with the expected molecular weight. Disulfide bonds' positions in M7 lysin were highly conservative, which was similar to C-type lectin carbohydrates identification area(CRD). We speculated that M7 lysin dissolved the yolk membrane through combining its sugar and sugar-based protein. The conclusions helped us to reveal the mussel' s reproductive mechanism, and further provide a reference for the cross breeding of mussels.%M7 lysin位于贻贝精子顶体中,是溶解卵黄膜、促进受精作用的重要蛋白质,决定了贻贝种间精卵识别的特异性.采用同源克隆法得到厚壳贻贝M7 lysin分子,并在原核生物中对该分子进行重组表达.

  13. Environmental proteomics of the mussel Mytilus: implications for tolerance to stress and change in limits of biogeographic ranges in response to climate change.

    Science.gov (United States)

    Tomanek, Lars

    2012-11-01

    Climate change will affect temperature extremes and averages, and hyposaline conditions in coastal areas due to extreme precipitation events and oceanic pH. How climate change will push species close to, or beyond, their physiological tolerance limits as well as change the limits of their biogeographic ranges can probably be investigated best in species that have already responded to climate change and whose distribution ranges are currently in flux. Blue mussels provide such a study system, with the invading warm-adapted Mediterranean Mytilus galloprovincialis having replaced the native more cold-adapted Mytilus trossulus from the southern part of its range in southern California over the past century, possibly due to climate change. However, freshwater input may prevent the latter species from expanding further north. We used a proteomics approach to characterize the responses of the two congeners to acute heat stress, chronic thermal acclimation, and hyposaline stress. In addition, we investigated the proteomic changes in response to decreasing seawater pH in another bivalve, the eastern oyster Crassostrea virginica. The results suggest that reactive oxygen species (ROS) are a common costressor during environmental stress, including oceanic acidification, and possibly cause modifications of cytoskeletal elements. All stressors disrupted protein homeostasis, indicated by the induction of molecular chaperones and, in the case of acute heat stress, proteasome isoforms, possibly due both to protein denaturation directly by the stressor and to the production of ROS. Acute stress by heat and hyposalinity changed several small G-proteins implicated in cytoskeletal modifications and vesicular transport, respectively. Changes in abundance of proteins involved in energy metabolism and ROS scavenging further suggest a possible trade-off during acute and chronic stress from heat and cold between ROS-generating NADH-producing pathways and ROS-scavenging NADPH

  14. Protozoan parasites of bivalve molluscs: literature follows culture.

    Science.gov (United States)

    Fernández Robledo, José A; Vasta, Gerardo R; Record, Nicholas R

    2014-01-01

    Bivalve molluscs are key components of the estuarine environments as contributors to the trophic chain, and as filter -feeders, for maintaining ecosystem integrity. Further, clams, oysters, and scallops are commercially exploited around the world both as traditional local shellfisheries, and as intensive or semi-intensive farming systems. During the past decades, populations of those species deemed of environmental or commercial interest have been subject to close monitoring given the realization that these can suffer significant decline, sometimes irreversible, due to overharvesting, environmental pollution, or disease. Protozoans of the genera Perkinsus, Haplosporidium, Marteilia, and Bonamia are currently recognized as major threats for natural and farmed bivalve populations. Since their identification, however, the variable publication rates of research studies addressing these parasitic diseases do not always appear to reflect their highly significant environmental and economic impact. Here we analyzed the peer- reviewed literature since the initial description of these parasites with the goal of identifying potential milestone discoveries or achievements that may have driven the intensity of the research in subsequent years, and significantly increased publication rates. Our analysis revealed that after initial description of the parasite as the etiological agent of a given disease, there is a time lag before a maximal number of yearly publications are reached. This has already taken place for most of them and has been followed by a decrease in publication rates over the last decade (20- to 30- year lifetime in the literature). Autocorrelation analyses, however, suggested that advances in parasite purification and culture methodologies positively drive publication rates, most likely because they usually lead to novel molecular tools and resources, promoting mechanistic studies. Understanding these trends should help researchers in prioritizing research

  15. Analysis of passion fruit rinds (Passiflora edulis: isoorientin quantification by HPTLC and evaluation of antioxidant (radical scavenging capacity

    Directory of Open Access Journals (Sweden)

    Maria Luiza Zeraik

    2012-01-01

    Full Text Available The content of isoorientin in passion fruit rinds (Passiflora edulis fo. flavicarpa O. Degener was determined by HPTLC (high performance thin layer chromatography with densitometric analysis. The results revealed a higher amount of isoorientin in healthy rinds of P. edulis (92.275 ± 0.610 mg L-1 than in rinds with typical symptoms of PWV (Passion fruit Woodiness Virus infection (28.931 ± 0.346 mg L-1. The HPTLC data, allied to assays of radical scavenging activity, suggest the potential of P. edulis rinds as a natural source of flavonoids or as a possible functional food.

  16. Interspecies comparison of the mechanical properties and biochemical composition of byssal threads.

    Science.gov (United States)

    Bouhlel, Zeineb; Genard, Bertrand; Ibrahim, Neilly; Carrington, Emily; Babarro, José M F; Lok, Aynur; Flores, Augusto A V; Pellerin, Christian; Tremblay, Réjean; Marcotte, Isabelle

    2017-03-15

    Several bivalve species produce byssus threads to provide attachment to substrates, with mechanical properties highly variable among species. Here, we examined the distal section of byssal threads produced by a range of bivalve species (Mytilus edulis, Mytilus trossulus, Mytilus galloprovincialis, Mytilus californianus, Pinna nobilis, Perna perna, Xenostrobus securis, Brachidontes solisianus and Isognomon bicolor) collected from different nearshore environments. Morphological and mechanical properties were measured, and biochemical analyses were performed. Multivariate redundancy analyses on mechanical properties revealed that byssal threads of M. californianus, M. galloprovincialis and P. nobilis have very distinct mechanical behaviours compared with the remaining species. Extensibility, strength and force were the main variables separating these species groups, which were highest for M. californianus and lowest for P. nobilis Furthermore, the analysis of the amino acid composition revealed that I. bicolor and P. nobilis threads are significantly different from the other species, suggesting a different underlying structural strategy. Determination of metal contents showed that the individual concentration of inorganic elements varies, but that the dominant elements are conserved between species. Altogether, this bivalve species comparison suggests some molecular bases for the biomechanical characteristics of byssal fibres that may reflect phylogenetic limitations.

  17. Determination of the variability of both hydrophilic and lipophilic toxins in endemic wild bivalves and carnivorous gastropods from the southern part of Chile.

    Science.gov (United States)

    Zamorano, Ruben; Marín, Michelle; Cabrera, Fabiola; Figueroa, Diego; Contreras, Cristóbal; Barriga, Andrés; Lagos, Néstor; García, Carlos

    2013-01-01

    The aim of this study was to analyse and determine the composition of paralytic shellfish poisoning (PSP) toxins and lipophilic toxins in the Region of Aysén, Chile, in wild endemic mussels (Mytilus chilensis, Venus antiqua, Aulacomya ater, Choromytilus chorus, Tagelus dombeii and Gari solida) and in two endemic carnivorous molluscs species (Concholepas concholepas and Argobuccinum ranelliforme). PSP-toxin contents were determined by using HPLC with fluorescence detection, while lipophilic toxins were determined by using LC-MS/MS. Mean concentrations for the total of PSP toxins were in the range 55-2505 μg saxitoxin-equivalent/100 g. The two most contaminated samples for PSP toxicity were bivalve Gari solida and carnivorous Argobuccinum ranelliforme with 2505 ± 101 and 1850 ± 137 μg saxitoxin-equivalent/100 g, respectively (p < 0.05). The lipophilic toxins identified were okadaic acid, dinophysistoxin-1 (DTX-1), azaspiracid-1 (AZA-1), pectenotoxin-2 (PTX-2) and yessotoxins (YTX). All analysed molluscs contained lipophilic toxins at levels ranging from 56 ± 4.8 to 156.1 ± 8.2 μg of okadaic acid-equivalent/kg shellfish together with YTX at levels ranging from 1.0 ± 0.1 to 18 ± 0.9 μg of YTX-equivalent/kg shellfish and AZA at levels ranging from 3.6 ± 0.2 to 31 ± 2.1 μg of AZA-equivalent/kg shellfish. Furthermore, different bivalves and gastropods differ in their capacity of retention of lipophilic toxins, as shown by the determination of their respective lipophilic toxins levels. In all the evaluated species, the presence of lipophilic toxins associated with biotransformation in molluscs and carnivorous gastropods was not identified, in contrast to the identification of PSP toxins, where the profiles identified in the different species are directly related to biotransformation processes. Thus, this study provides evidence that the concentration of toxins in the food intake of the evaluated species (Bivalvia and Gastropoda class) determines the degree of

  18. Epidemiology of Bonamia ostreae infecting European flat oysters (Ostrea edulis) from Lake Grevelingen, The Netherlands

    NARCIS (Netherlands)

    Engelsma, M.Y.; Kerkhoff, S.; Roozenburg, I.; Haenen, O.L.M.; van Gool, A.; Sistermans, W.C.H.; Wijnhoven, S.; Hummel, H.

    2010-01-01

    Production of European flat oysters Ostrea edulis in the Netherlands has been hampered by the presence of the haplosporidian parasite Bonamia ostreae, which is now an enzootic species following its establishment after 1980. We analyzed histopathological data from annual shellfish disease monitoring

  19. Epidemiology of Bonamia ostrea infecting European flat oysters Ostrea edulis from Lake Grevelingen, The Netherlands

    NARCIS (Netherlands)

    Engelsma, M.Y.; Kerkhoff, S.; Roozenburg, I.; Haenen, O.L.M.; Gool, van A.C.M.

    2010-01-01

    Production of European flat oysters Ostrea edulis in the Netherlands has been hampered by the presence of the haplosporidian parasite Bonamia ostreae, which is now an enzootic species following its establishment after 1980. We analyzed histopathological data from annual shellfish disease monitoring

  20. Bioconcentration and biotransformation of [¹⁴C]methoxychlor in the brackish water bivalve Corbicula japonica.

    Science.gov (United States)

    Masuda, Minoru; Ohyama, Kazutoshi; Hayashi, Osamu; Satsuma, Koji; Sato, Kiyoshi

    2011-09-01

    To obtain basic information on the metabolic fate of xenobiotics in the brackish water, bivalve Corbicula japonica, bioconcentration and biotransformation experiments were performed using methoxychlor (MXC) as a model compound. Bivalves were exposed to [ring-U-¹⁴C]MXC (10 µg L⁻¹) for 28 days under semi-static conditions followed by a 14-day depuration phase. The ¹⁴C concentration in the bivalves rapidly increased and reached a steady state after exposure for 7 days (BCFss = 2010); however, it rapidly decreased with a half-life of 2.2 days in the depuration phase. Mono- and bis-demethylated MXC, and their corresponding sulphate conjugates, were identified as minor metabolites. No glycoside conjugates (including glucuronide and glucoside) were detected. Despite this biotransformation system, bivalves were found to excrete retained MXC mostly unchanged although its relatively hydrophobic nature.

  1. Effect of different extraction procedures on antimicrobial activity of marine bivalves: A comparison

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, S.; Chatterji, A.; Das, P.

    Anti-bacterial activity was evaluated in different crude extracts of five commercially important edible marine bivalves, namely Meretrix casta (Chemnitz), Polymesoda (Geloina) P. erosa (Solander), Perna viridis (Linnaeus), Crassostrea gryphoides...

  2. Hydraulic architecture and photoinhibition influence spatial distribution of the arborescent palm Euterpe edulis in subtropical forests.

    Science.gov (United States)

    Gatti, M Genoveva; Campanello, Paula I; Villagra, Mariana; Montti, Lía; Goldstein, Guillermo

    2014-06-01

    Physiological characteristics of saplings can be considered one of the most basic constraints on species distribution. The shade-tolerant arborescent palm Euterpe edulis Mart. is endemic to the Atlantic Forest of Argentina, Brazil and Paraguay. At a local scale, saplings of this species growing in native forests are absent in gaps. We tested the hypothesis whether sensitivity to photoinhibition or hydraulic architecture constrains the distribution of E. edulis saplings in sun-exposed forest environments. Using shade houses and field studies, we evaluated growth, survival, hydraulic traits and the susceptibility of Photosystem II to photoinhibition in E. edulis saplings under different growth irradiances. Survival rates in exposed sites in the field were very low (a median of 7%). All saplings exhibited photoinhibition when exposed to high radiation levels, but acclimation to a high radiation environment increased the rate of recovery. Petiole hydraulic conductivity was similar across treatments regardless of whether it was expressed per petiole cross-sectional area or per leaf area. At the plant level, investment in conductive tissues relative to leaf area (Huber values) increased with increasing irradiance. Under high irradiance conditions, plants experienced leaf water potentials close to the turgor-loss point, and leaf hydraulic conductance decreased by 79% relative to its maximum value. Euterpe edulis saplings were able to adjust their photosynthetic traits to different irradiance conditions, whereas hydraulic characteristics at the leaf level did not change across irradiance treatments. Our results indicate that uncoupling between water demand and supply to leaves apparently associated with high resistances to water flow at leaf insertion points, in addition to small stems with low water storage capacity, weak stomatal control and high vulnerability of leaves to hydraulic dysfunction, are the main ecophysiological constraints that prevent the growth and

  3. [Energy metabolism and body mass ratio in bivalves mollusca (Mollusca: Bivalvia)].

    Science.gov (United States)

    Vladimirova, I G; Kleĭmenov, S Iu; Radzinskaia, L I

    2003-01-01

    On the basis of experimental and published data, the interspecific and intraspecific (ontogenetic) dependence of energy metabolism on body weight in bivalves was calculated. Changes in the parameters of intraspecific allometric dependence under the effect of environmental factors were analyzed. The rate of comparable standard metabolism (coefficient a at k = 0.76) was shown to vary in different taxonomic and zoogeographic groups of bivalves.

  4. Influence of intertidal recreational fisheries and 'bouchot' mussel culture on bivalve recruitment.

    Science.gov (United States)

    Toupoint, Nicolas; Barbier, Pierrick; Tremblay, Réjean; Archambault, Philippe; McKindsey, Christopher W; Winkler, Gesche; Meziane, Tarik; Olivier, Frédéric

    2016-06-01

    In coastal environments, fishing and aquaculture may be important sources of disturbance to ecosystem functioning, the quantification of which must be assessed to make them more sustainable. In the Chausey Archipelago, France, recreational fishing and commercial shellfish farming are the only two evident anthropogenic activities, dominated by bivalve hand-raking and 'bouchot' mussel culture, respectively. This study evaluates the impact of both activities on bivalve recruitment dynamics by comparing primary recruitment intensity (short-term effect) and recruitment efficiency (medium-term effect) by sampling bivalves in reference (undisturbed) and disturbed (i.e. subjected to hand-raking or in 'bouchot' mussel culture areas) parcels throughout and at the end of the recruitment season, respectively. Specific hypotheses evaluated were that (H1) bivalve hand-raking negatively affects bivalve recruitment and that (H2) 'bouchot' mussel culture promotes bivalve recruitment. Patterns in bivalve community structure in reference parcels (i.e. natural pattern) differed between initial and final recruitment, underlining the great importance of early post-settlement processes, particularly secondary dispersal. Primary recruitment intensity was inhibited in hand-raking parcels whereas it was promoted in 'bouchot' mussel culture parcels, but the effect on recruitment efficiency was muted for both activities due to post-settlement processes. Nevertheless, the importance of effects that occur during the first step of recruitment should not be ignored as they may affect bivalve communities and induce immediate consequences on the trophic web through a cascade effect. Finally, it is highlighted that hand-raking damages all life stages of the common cockle Cerastoderma edule, one of the major target species, suggesting that this activity should be managed with greater caution than is currently done.

  5. Hyperunstable matrix proteins in the byssus of Mytilus galloprovincialis.

    Science.gov (United States)

    Sagert, Jason; Waite, J Herbert

    2009-07-01

    The marine mussel Mytilus galloprovincialis is tethered to rocks in the intertidal zone by a holdfast known as the byssus. Functioning as a shock absorber, the byssus is composed of threads, the primary molecular components of which are collagen-containing proteins (preCOLs) that largely dictate the higher order self-assembly and mechanical properties of byssal threads. The threads contain additional matrix components that separate and perhaps lubricate the collagenous microfibrils during deformation in tension. In this study, the thread matrix proteins (TMPs), a glycine-, tyrosine- and asparagine-rich protein family, were shown to possess unique repeated sequence motifs, significant transcriptional heterogeneity and were distributed throughout the byssal thread. Deamidation was shown to occur at a significant rate in a recombinant TMP and in the byssal thread as a function of time. Furthermore, charge heterogeneity presumably due to deamidation was observed in TMPs extracted from threads. The TMPs were localized to the preCOL-containing secretory granules in the collagen gland of the foot and are assumed to provide a viscoelastic matrix around the collagenous fibers in byssal threads.

  6. Probing the adhesive footprints of Mytilus californianus byssus.

    Science.gov (United States)

    Zhao, Hua; Robertson, Nicholas B; Jewhurst, Scott A; Waite, J Herbert

    2006-04-21

    California mussels Mytilus californianus owe their tenacity to a holdfast known as the byssus, a fibrous extracellular structure that ends distally in flattened adhesive plaques. The "footprints" of freshly secreted plaques deposited onto glass coverslips were shown by matrix-assisted laser desorption ionization time of flight mass spectrometry to consist chiefly of proteins ranging in mass from 5200 to 6700 Da. These proteins, variants of a family known as mcfp3 (M. californianus foot protein 3), were purified from acetic acid/urea extracts of plaques and foot tissue. Mcfp3 appears to sort into fast and slow electrophoretic variants. Both are rich in Gly and Asn and exhibit post-translational hydroxylation of Tyr and Arg to Dopa and 4-hydroxyarginine, respectively, with the fast variant containing more than twice as much Lys + Arg. Both the slow and fast variants were partially sequenced from the N terminus, and the complete sequences of 12 variants were deduced from cDNA using degenerate oligonucleotides, PCR, and rapid amplification of cDNA ends. Mcfp3s are highly polar molecules and contain up to 28 mol % Dopa, which remains intact and may be crucial for adhesion to metal and mineral surfaces.

  7. Effects of silver nanoparticles exposure in the mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Gomes, Tânia; Pereira, Catarina G; Cardoso, Cátia; Sousa, Vânia Serrão; Teixeira, Margarida Ribau; Pinheiro, José P; Bebianno, Maria João

    2014-10-01

    Silver nanoparticles (Ag NPs) have emerged as one of the most commonly used NPs in a wide range of industrial and commercial applications. This has caused increasing concern about their fate in the environment as well as uptake and potential toxicity towards aquatic organisms. Accordingly, mussels Mytilus galloprovincialis were exposed to 10 μg L(-1) of Ag NPs and ionic silver (Ag+) for 15 days, and biomarkers of oxidative stress and metal accumulation were determined. Accumulation results show that both Ag NPs and Ag+ accumulated in both gills and digestive glands. Antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were activated by Ag NPs and Ag+, showing different antioxidant patterns in both gills and digestive glands. Moreover, metallothionein was inducted in gills, directly related to Ag accumulation, while in the digestive glands only a small fraction of Ag seems to be associated with this protein. Lipid peroxidation was higher in gills exposed to Ag NPs, whereas in the digestive glands only Ag+ induced lipid peroxidation. Ag NPs and Ag+ cause oxidative stress with distinct modes of action and it's not clear if for Ag NPs the observed effects are attributed to free Ag+ ions associated with the nanoparticle effect.

  8. Biochemical and histological alterations of Mytilus galloprovincialis digestive gland

    Directory of Open Access Journals (Sweden)

    R Auriemma

    2004-11-01

    Full Text Available Electrophoretical and histological analysis were performed on Mytilus galloprovincialis digestivegland samples, in order to detect the presence of a previously identified protein ca 30 kDa MW,synthesized during Dinophysis spp. blooms, and assess a possible correlation between the occurrenceof this protein and okadaic acid (OA exposure by ingestion. Mussels were sampled monthly from July2000 to November 2001 in the Gulf of Trieste (upper Adriatic Sea and immediately processed. Parallelsamples were maintained in sea water plastic tanks and fed with marine invertebrate feed mixed withOA and derivatives at different concentration of toxins for each experimental group (25 mg, 50 mg, 100mg. In tank reared mussels fed with OA, degeneration of digestive cells and appearance of 24.6 kDaprotein were observed, while in wild mussels, neither histological alterations nor presence of a 24.6kDa protein, were detected. A correlation between the toxins concentration and time of appearancewas highlighted, to demonstrate this protein is synthesized in response to OA and derivativesexposure. About the identity of 24.6 kDa protein, it could be an enzyme involved in detoxificationreactions, probably Glyoxalase I.

  9. Cholinesterase activity in the tissues of bivalves Noah's ark shell (Arca noae) and warty venus (Venus verrucosa): characterisation and in vitro sensitivity to organophosphorous pesticide trichlorfon.

    Science.gov (United States)

    Perić, Lorena; Ribarić, Luka; Nerlović, Vedrana

    2013-08-01

    Cholinesterase (ChE, EC 3.1.1.7) activity was investigated in gills and adductor muscle of two bivalve species: Arca noae and Venus verrucosa. The properties of ChEs were investigated using acetylcholine iodide (ASCh), butyrylcholine iodide (BSCh) and propionylcholine iodide (PrSCh) as substrates and eserine, BW254c51 and iso-OMPA as specific inhibitors. The highest level of ChE activity in crude tissue extracts was detected with PrSCh followed by ASCh, while values obtained with BSCh were apparently low, except in A. noae adductor muscle. The enzyme activity in A. noae gills and V. verrucosa gills and adductor muscle was significantly inhibited by BW254c51, but not with iso-OMPA. ChE activity in adductor muscle of A. noae was significantly reduced by both diagnostic inhibitors. The effect of organophosphorous pesticide trichlorfon on ChE activity was investigated in vitro in both species as well as in the gills of mussels Mytilus galloprovincialis. The highest sensitivity of ChE to trichlorfon was observed in A. noae gills and adductor muscle (IC50 1.6×10(-7)M and 1.1×10(-7)M, respectively), followed by M. galloprovincialis gills (IC50 1.0×10(-6)M) and V. verrucosa gills and adductor muscle (IC50 1.7×10(-5)M and 0.9×10(-5)M, respectively). The results of this study suggest the potential of ChE activity measurement in the tissues of A. noae as effective biomarker of OP exposure in marine environment.

  10. eDNA and specific primers for early detection of invasive species--A case study on the bivalve Rangia cuneata, currently spreading in Europe.

    Science.gov (United States)

    Ardura, Alba; Zaiko, Anastasija; Martinez, Jose L; Samulioviene, Aurelija; Semenova, Anna; Garcia-Vazquez, Eva

    2015-12-01

    Intense human activities facilitate the successful spread and establishment of non-indigenous aquatic organisms in marine and freshwater ecosystems. In some cases such intrusions result in noticeable and adverse changes in the recipient environments. In the Baltic Sea, the discovery and rapid initial spread of the North American wedge clam Rangia cuneata represents a new wave of invasion which may trigger unpredictable changes of the local benthic communities. In this study we present a species-specific DNA-based marker developed in silico and experimentally tested on environmental samples. Marker specificity and sensitivity were assessed in vitro from water samples containing different mixtures of the target species and other five bivalves currently present in the region: the native Cerastoderma glaucum, Macoma balthica and Mytilus trossulus, the invasive Dreissena polymorpha and the cryptogenic Mya arenaria. Cross-species amplification was not found in any case. The method allows to detecting at least 0.4 ng of R. cuneata DNA per μl, and 0.1 g of tissue per liter of water. Finally, the marker performance was assessed in water samples from the Baltic Sea and Vistula Lagoon. The coincidence between independent visual observations of R. cuneata and positive PCR amplification of the marker from the water samples confirmed the efficiency of this highly reproducible, fast, and technically easy method. R. cuneata traces can be detected from environmental DNA even when the population is sparse and small, enabling rapid management responses and allowing to track the invasion dynamics.

  11. Determination of radionuclides in Mytilus galloprovicialis by Alpha And Gamma-Spectroscopy

    Directory of Open Access Journals (Sweden)

    H. FLOROU

    2012-12-01

    Full Text Available The natural radionuclides 238U ,234Th, 40K and the main man-made 137Cs, have been studied in Mytilus galloprovincialis (Lamarck, 1819 sampled in the Thermaikos gulf – North Aegean Sea, considered as a bioindicator for radiological assessment in the Mediterranean. The ratio 234U/238U has also been determined. In terms of 137Cs, the activity concentrations in seawater from the studied area have been measured as well, and the concentration factors of 137Cs in Mytilus galloprovincialis are given as a parameter of the organism response to radioactive pollution.

  12. Histopathological assessment and inflammatory response in the digestive gland of marine mussel Mytilus galloprovincialis exposed to cadmium-based quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Thiago Lopes [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás (Brazil); Sabóia-Morais, Simone Maria Teixeira [Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás (Brazil); Bebianno, Maria João, E-mail: mbebian@ualg.pt [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2016-08-15

    Highlights: • Digestive gland of marine mussels is target for Cd-based QDs toxicity. • Both Cd forms increase the frequency of atrophic digestive tubules in a time dependent pattern. • QDs induce higher inflammatory responses when compared to dissolved Cd. • Multiparametric tissue-levels biomarkers show distinct mode of action in the digestive gland. - Abstract: Although tissue-level biomarkers have been widely applied in environmental toxicology studies, the knowledge using this approach in marine invertebrates exposed to engineered nanomaterials (ENMs) remains limited. This study investigated histopathological alterations and inflammatory responses induced by Cd-based quantum dots (QDs), in comparison with their dissolved counterparts, in the marine mussel Mytilus galloprovincialis. Mussels were exposed to CdTe QDs and dissolved Cd at the same concentration (10 μg Cd L{sup −1}) for 14 days and a total of 15 histopathological alterations and 17 histomorphometric parameters were analysed in the digestive gland along with the determination of histopathological condition indices (I{sub h}). A multivariate analysis showed that the mussel response to QDs was more related to exposure time, inflammatory conditions (frequency of haemocytic infiltration and granulocytomas) and changes of cell-type composition (especially the rate between basophilic and digestive cells) when compared to dissolved Cd, while the response to dissolved Cd was associated with histomorphometric parameters of the epithelium and lumen of digestive tubules and increase of the atrophic tubule frequency. Both Cd forms induced higher I{sub h} compared to unexposed mussels indicating a significant decrease in the health status of digestive gland in a Cd form and time-dependent pattern. Results indicate that the multiparametric tissue-level biomarkers in the digestive gland provide a suitable approach to assess the ecotoxicity and mode of action of metal-based ENMs in marine bivalves.

  13. cDNA and Gene Structure of MytiLec-1, A Bacteriostatic R-Type Lectin from the Mediterranean Mussel (Mytilus galloprovincialis).

    Science.gov (United States)

    Hasan, Imtiaj; Gerdol, Marco; Fujii, Yuki; Rajia, Sultana; Koide, Yasuhiro; Yamamoto, Daiki; Kawsar, Sarkar M A; Ozeki, Yasuhiro

    2016-01-01

    MytiLec is an α-d-galactose-binding lectin with a unique primary structure isolated from the Mediterranean mussel (Mytilus galloprovincialis). The lectin adopts a β-trefoil fold that is also found in the B-sub-unit of ricin and other ricin-type (R-type) lectins. We are introducing MytiLec(-1) and its two variants (MytiLec-2 and -3), which both possess an additional pore-forming aerolysin-like domain, as members of a novel multi-genic "mytilectin family" in bivalve mollusks. Based on the full length mRNA sequence (911 bps), it was possible to elucidate the coding sequence of MytiLec-1, which displays an extended open reading frame (ORF) at the 5' end of the sequence, confirmed both at the mRNA and at the genomic DNA sequence level. While this extension could potentially produce a polypeptide significantly longer than previously reported, this has not been confirmed yet at the protein level. MytiLec-1 was revealed to be encoded by a gene consisting of two exons and a single intron. The first exon comprised the 5'UTR and the initial ATG codon and it was possible to detect a putative promoter region immediately ahead of the transcription start site in the MytiLec-1 genomic locus. The remaining part of the MytiLec-1 coding sequence (including the three sub-domains, the 3'UTR and the poly-A signal) was included in the second exon. The bacteriostatic activity of MytiLec-1 was determined by the agglutination of both Gram-positive and Gram-negative bacteria, which was reversed by the co-presence of α-galactoside. Altogether, these data support the classification of MytiLec-1 as a member of the novel mytilectin family and suggest that this lectin may play an important role as a pattern recognition receptor in the innate immunity of mussels.

  14. Neurotoxicological effects on marine mussel Mytilus galloprovincialis caged at petrochemical contaminated areas (eastern Sicily, Italy): ¹H NMR and immunohistochemical assays.

    Science.gov (United States)

    Cappello, Tiziana; Maisano, Maria; Giannetto, Alessia; Parrino, Vincenzo; Mauceri, Angela; Fasulo, Salvatore

    2015-03-01

    The neurotoxicological potential of environmental pollution, mainly related to petrochemical activities, was investigated in marine mussel Mytilus galloprovincialis. Bivalve mollusks, particularly mussels, are widely used as sentinel organisms in biomonitoring studies for assessing the impact of anthropogenic contaminants. The gills, mainly involved in nutrient uptake, digestion, gas exchange and neuronal signaling, are the first organ to be affected by pollutants present in the external environment, and therefore were selected as the target organ for this study. Mussels from an aquaculture farm were caged at a highly polluted petrochemical area and a reference site along the Augusta coastline (eastern Sicily, Italy) for one month. A battery of biomarkers indicative of neuronal perturbations was applied on gills in order to investigate on the serotonergic (i.e. serotonin, 5-HT, and its receptor, 5-HT3R), cholinergic (i.e. acetylcholine, acetylcholinesterase, AChE, and choline acetyltransferase, ChAT), and dopaminergic systems (i.e. tyrosine and tyrosine hydroxylase, TH). Overall, impairment in the normal ciliary motility was found in mussels caged at the polluted site. Alterations in serotoninergic and cholinergic systems were revealed, with enhancement of dopaminergic neurotransmission resulting in a cilio-inhibitory effect. However, the over-expression in 5-HT3R and ChAT at cellular level may indicate an adaptive response of mussels to recover a regular physiological activity in gills. To our knowledge, this is the first study that uses (1)H NMR and immunohistochemical assays. Their concurrent use demonstrated to be sensitive and effective for assessing environmental influences on the health status of aquatic organisms, and thus suitable to be applied in ecotoxicological studies.

  15. The influence of agroforestry silviculture on productivity and quality of Canna edulis Ker on private forest land

    OpenAIRE

    A. Sudomo; Hani, A.

    2014-01-01

    The productivity of private forest land by using agroforestry of Canna edulis Ker aims to achieve food security at the smallholder level. The purpose of this study was to determine the effect of agroforestry cropping patterns on productivity and quality of Canna edulis Ker tuber on private forest land. The study was conducted in dry area of the private forest land who are administrativelyincluding Tenggerraharja Village area, SukamantriSubdistrict, Ciamis District, West Java Province, Indones...

  16. Anoxic survival potential of bivalves: (arte)facts.

    Science.gov (United States)

    de Zwaan, Albertus; Babarro, Jose M F; Monari, Marta; Cattani, Otello

    2002-03-01

    The anoxic survival time of the bivalves Chamelea gallina, Cerastoderma edule and Scapharca inaequivalvis from two different ecosystems and differing anoxia tolerances was studied in static (closed) and flow-through systems. The antibiotics chloramphenicol, penicillin and polymyxin were added, and molybdate (specific inhibitor of the process of sulfate reduction). Survival in (near) anoxic seawater of Chamelea was studied in a static system by comparing untreated seawater with autoclaved seawater and untreated clams with clams incubated in well-aerated seawater, containing the broad-spectrum antibiotic chloramphenicol, prior to the anoxic survival test. With untreated clams and natural seawater (median mortality time 2.4 days) a decrease in pH and exponential accumulation of sulfide and ammonium was observed in the anoxic medium, indicating excessive growth of (sulfate reducing) bacteria. In sterilized seawater LT50 (2.1 days) was not significantly different and again considerable amounts of ammonium and sulfide accumulated. However, pre-treatment of clams with chloramphenicol resulted in an increase of LT50 (11.0 days) by approximately fivefold. Accumulation of ammonium and sulfide was retarded, but was finally even stronger than in the medium containing untreated clams. Median mortality times were 2.5 and 2.4 days for Chamelea and 2.7 and 2.9 days for Cerastoderma for static and flow-through incubations, respectively. Addition of chloramphenicol increased strongly survival time in both systems with corresponding values of 11.0 and 16.3 days for Chamelea, and 6.4 and 6.5 days for Cerastoderma. LT50 of Scapharca in anoxic seawater was 14.4 days. Chloramphenicol and penicillin increased median survival time to 28.5 and 28.7 days, respectively, whereas polymyxin displayed no effect (LT50=13.6 days). Molybdate added to artificial sulfate free seawater blocked biotic sulfide formation, but did not improve survival time (LT50=13.7 days). Overall the results indicate

  17. Genomic characterization of the aquaculture resource Mytilus galloprovincialis

    Directory of Open Access Journals (Sweden)

    Maria Murgarella

    2014-06-01

    Full Text Available In the autonomous community of Galicia (NW Spain, M. galloprovincialis is a natural resource of high economic importance to the economy of this region. More than 250,000 MTs of mussels are produced per year, representing 40% of the European production of this bivalve and 80% of the marine aquacultural production of the country. Besides its aquaculture interest, study of the biology M. galloprovincialis may also help to understand better fundamental aspects of molluscan biology. On the other hand, some fascinating features of mediterranean mussels are unique to this species such as its extraordinary resistance to diseases. In fact, in comparison with other bivalves, no records of massive mortality of this organism caused by pathogens has been reported so far. Although some of the molecular components of the innate immune system, responsible of this resistance, have been previously identified and characterized, the genetic mechanisms underlying their diversity are poorly understood. In order to understand better this organism at genome level and search for the genetic basis of its disease resistance, we sequenced its genome at high depth using Illumina technology. After assembling the resulting reads and assisted with transcriptomic data, we annotated its genome sequence. First, we analysed the content of repetitive elements, finding those that are common among molluscs as well as identifying new repeat families unique to M. galloprovincialis. Second, we predicted and annotated its gene repertoire, defining the total number of genes and their density in its genome. Finally, the resulting in silico predicted genes were functionally annotated. Altogether, this information will allow the identification of genes of interest, such as those participating in the innate immunity and will allow us to delve into the possibility of whether their variability has a genetic basis or relies on post-transcriptional events. In addition to this annotation, some

  18. Different carbon sources affect PCB accumulation by marine bivalves.

    Science.gov (United States)

    Laitano, M V; Silva Barni, M F; Costa, P G; Cledón, M; Fillmann, G; Miglioranza, K S B; Panarello, H O

    2016-02-01

    Pampean creeks were evaluated in the present study as potential land-based sources of PCB marine contamination. Different carbon and nitrogen sources from such creeks were analysed as boosters of PCB bioaccumulation by the filter feeder bivalve Brachidontes rodriguezii and grazer limpet Siphonaria lessoni. Carbon of different source than marine and anthropogenic nitrogen assimilated by organisms were estimated through their C and N isotopic composition. PCB concentration in surface sediments and mollusc samples ranged from 2.68 to 6.46 ng g(-1) (wet weight) and from 1074 to 4583 ng g(-1) lipid, respectively, reflecting a punctual source of PCB contamination related to a landfill area. Thus, despite the low flow of creeks, they should not be underestimated as contamination vectors to the marine environment. On the other hand, mussels PCB bioaccumulation was related with the carbon source uptake which highlights the importance to consider this factor when studying PCB distribution in organisms of coastal systems.

  19. Effects of active pharmaceutical ingredients mixtures in mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Gonzalez-Rey, M; Mattos, J J; Piazza, C E; Bainy, A C D; Bebianno, M J

    2014-08-01

    Active pharmaceutical ingredients (APIs) are emergent environmental contaminants widely detected in surface waters as result of incomplete waste water treatment plant (WWTP) removal processes and improper disposal. The assessment of potential effects of APIs on non-target organisms is still scarce since besides presenting multiple chemical structures, properties and modes of action, these compounds occur as complex mixtures. This study comprises a 15-day exposure of mussels Mytilus galloprovincialis to mixtures (at environmentally relevant nominal concentrations) of non-steroidal inflammatory drugs ibuprofen (IBU) and diclofenac (DCF) (250 ng L(-1) each) and selective serotonin reuptake inhibitor (SSRI) fluoxetine (FLX) (75 ng L(-1)) (MIX 1) along with the addition of classical pro-oxidant copper (Cu) (5 μg L(-1)) (MIX 2). The goals included the assessment of oxidative stress, neurotoxic and endocrine effects on this sentinel species applying both a multibiomarker and gene expression (here and later gene expression is taken as synonym to gene transcription, although it is acknowledged that it is also affected by, e.g. translation, and mRNA and protein stability) analysis approaches. The results revealed a swifter antioxidant response in digestive glands than in gills induced by MIX 1, nevertheless the presence of Cu in MIX 2 promoted a higher lipid peroxidation (LPO) induction. Neither mixture altered acetylcholinesterase (AChE) activity, while both triggered the formation of vitellogenin-like proteins in females confirming the xenoestrogenic effect of mixtures. All these results varied with respect to those obtained in previous single exposure essays. Moreover, RT-PCR analysis revealed a catalase (CAT) and CYP4Y1 gene expression down- and upregulation, respectively, with no significant changes in mRNA levels of genes encoding superoxide dismutase (SOD) and glutathione-S-transferase (GST). Finally, this study highlights variable tissue and time-specific biomarker

  20. Changing restoration rules: exotic bivalves interact with residence time and depth to control phytoplankton productivity

    Science.gov (United States)

    Lucas, Lisa V.; Thompson, Janet K.

    2012-01-01

    Non-native species are a prevalent ecosystem stressor that can interact with other stressors to confound resource management and restoration. We examine how interactions between physical habitat attributes and a particular category of non-native species (invasive bivalves) influence primary production in aquatic ecosystems. Using mathematical models, we show how intuitive relationships between phytoplankton productivity and controllable physical factors (water depth, hydraulic transport time) that hold in the absence of bivalves can be complicated—and even reversed—by rapid bivalve grazing. In light-limited environments without bivalves, shallow, hydrodynamically “slow” habitats should generally have greater phytoplankton biomass and productivity than deeper, “faster” habitats. But shallower, slower environments can be less productive than deeper, faster ones if benthic grazing is strong. Moreover, shallower and slower waters exhibit a particularly broad range of possible productivity outcomes that can depend on whether bivalves are present. Since it is difficult to predict the response of non-native bivalves to habitat restoration, outcomes for new shallow, slow environments can be highly uncertain. Habitat depth and transport time should therefore not be used as indicators of phytoplankton biomass and production where bivalve colonization is possible. This study provides for ecosystem management a particular example of a broad lesson: abiotic ecosystem stressors should be managed with explicit consideration of interactions with other major (including biotic) stressors. We discuss the applicability and management implications of our models and results for a range of aquatic system types, with a case study focused on the Sacramento-San Joaquin Delta (California, USA). Simple mathematical models like those used here can illuminate interactions between ecosystem stressors and provide process-based guidance for resource managers as they develop strategies

  1. [The byssus of Mytilus: electrophoresis of hydroxyproline-rich proteins from the "collagen gland"].

    Science.gov (United States)

    Pujol, J P; Bocquet, J; Borel, J P

    1976-09-20

    An hydroxyproline rich fraction has been extracted from the byssus gland of Mytilus. This fraction could be the intracellular precursor of the "secreted collagen" found in the byssus threads. Its molecular weight, estimated through SDS gel electrophoresis, appears lower than that of a chains of mesenchymal collagen.

  2. The respiratory capacity of marine mussels (Mytilus galloprovincialis) in relation to the high temperature threshold

    NARCIS (Netherlands)

    Jansen, J.M.; Hummel, H.; Bonga, S.W.

    2009-01-01

    Thermal tolerance limits of ectotherms may result from respiratory limitations. In response to declining oxygen availability, organisms have shown to exhibit oxyregulation by enhancing ventilation and heartbeat rates. In this study we examined how this regulatory response in mussels (Mytilus) change

  3. Distribution of Mytilus taxa in European coastal areas as inferred from molecular markers

    NARCIS (Netherlands)

    Kijewski, T.; Zmietanka, B.; Zbawicka, M.; Gosling, E.; Hummel, H.; Wenne, R.

    2011-01-01

    The genetic constitution of mussels (Mytilus spp.) was studied by means of three nuclear (Me 15/16, EF-bis, ITS) and one mtDNA (ND2-COIII) marker on a large European scale. In addition to a sharp cline between Atlantic and Mediterranean M. galloprovincialis, we observed a clear genetic distinction b

  4. Genetic diversity and connectivity within Mytilus spp. in the subarctic and Arctic

    DEFF Research Database (Denmark)

    Mathiesen, Sofie Smedegaard; Thyrring, Jakob; Hansen, Jakob Hemmer;

    2017-01-01

    Climate changes in the Arctic are predicted to alter distributions of marine species. However, such changes are difficult to quantify because information on present species distribution and the genetic variation within species is lacking or poorly examined. Blue mussels, Mytilus spp., are ecosyst...

  5. The influence of agroforestry silviculture on productivity and quality of Canna edulis Ker on private forest land

    Directory of Open Access Journals (Sweden)

    A. Sudomo

    2014-04-01

    Full Text Available The productivity of private forest land by using agroforestry of Canna edulis Ker aims to achieve food security at the smallholder level. The purpose of this study was to determine the effect of agroforestry cropping patterns on productivity and quality of Canna edulis Ker tuber on private forest land. The study was conducted in dry area of the private forest land who are administrativelyincluding Tenggerraharja Village area, SukamantriSubdistrict, Ciamis District, West Java Province, Indonesia. The planting of Canna edulis Ker was implemented under the 32 months old Manglieta glauca BI stands. The main plots were three pruning intensity of Manglietia glauca BI stands i.e. P0 (0 % , P1 (50%, and P2 (75%. The sub plots were three planting spaces of Manglietia glauca BI, i.e. S1 (2m x 2m, S2 (2m x 3 m, and S3 (3m x 3m. The planting of Canna edulis Ker by monoculture technique was conducted as a comparison. The results showed that the interaction of planting space and pruning intensity gave a significant result on height growth, wet weight and dry weight of plant, wet weight and dry weight of Canna edulis Ker tuber. The growth of Canna edulis Ker that ranged from 181.85 cm (P0S1 to 186.30 cm (P1S1 were higher than the monoculture system on Canna edulis Ker (138.20 cm. The wet weight and dry weight of tuber that ranged from 2089.3 g and 1429.99 g (P2J2 to 3695.5 g and 2678.09 g (P1S2, whreas those in the monoculture system on Canna edulis Ker were 2363.1 g and 1528.7 g. However, the protein, fiber and carbohydrate contents of P0S1, P1S1, P2S1 treatments were lower than those of the monoculture system on Canna edulis Ker. The planting pattern of agroforestry were able to improve the plant height of Canna edulis Ker tuber but giving less percentage of carbohydrate and protein of tuber than the monoculture

  6. KOMPOSISI KIMIA BIJI DAN SIFAT FUNGSIONAL PATI GAYAM (Inocarpus edulis Forst.) [Chemical Composition of Gayam (Inocarpus edulis Forst.) Seed and Functional Properties of Its Starch

    OpenAIRE

    2002-01-01

    Basic information on physical and chemical properties of Gayam (Inocarpus edulis Forst), one of the domestic commodities, is still very limited. The objectives of this research were to investigate chemical composition of gayam seed and the functional properties of gayam starch, especially the pasting behavior and the characteristic of its gel.Moisture, crude protein, lipid, ash, and carbohydrate content of gayam seed, respectively, were 50.11% (w/w), 11.66%, 8.21 %, 3.39% , and 76.74% (dw). ...

  7. The earliest post-paleozoic freshwater bivalves preserved in coprolites from the karoo basin, South Africa.

    Directory of Open Access Journals (Sweden)

    Adam M Yates

    Full Text Available BACKGROUND: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic. PRINCIPAL FINDINGS: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative. CONCLUSIONS: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.

  8. Chitin in the silk gland ducts of the spider Nephila edulis and the silkworm Bombyx mori.

    Directory of Open Access Journals (Sweden)

    Gwilym J G Davies

    Full Text Available Here we report the detection and localisation of chitin in the cuticle of the spinning ducts of both the spider Nephila edulis and the silkworm Bombyx mori. Our observations demonstrate that the duct walls of both animals contain chitin notwithstanding totally independent evolutionary pathways of the systems. We conclude that chitin may well be an essential component for the construction of spinning ducts; we further conclude that in both species chitin may indicate the evolutionary origin of the spinning ducts.

  9. Chitin in the silk gland ducts of the spider Nephila edulis and the silkworm Bombyx mori.

    Science.gov (United States)

    Davies, Gwilym J G; Knight, David P; Vollrath, Fritz

    2013-01-01

    Here we report the detection and localisation of chitin in the cuticle of the spinning ducts of both the spider Nephila edulis and the silkworm Bombyx mori. Our observations demonstrate that the duct walls of both animals contain chitin notwithstanding totally independent evolutionary pathways of the systems. We conclude that chitin may well be an essential component for the construction of spinning ducts; we further conclude that in both species chitin may indicate the evolutionary origin of the spinning ducts.

  10. Chitin in the Silk Gland Ducts of the Spider Nephila edulis and the Silkworm Bombyx mori

    OpenAIRE

    Davies, Gwilym J. G.; Knight, David P; Fritz Vollrath

    2013-01-01

    Here we report the detection and localisation of chitin in the cuticle of the spinning ducts of both the spider Nephila edulis and the silkworm Bombyx mori. Our observations demonstrate that the duct walls of both animals contain chitin notwithstanding totally independent evolutionary pathways of the systems. We conclude that chitin may well be an essential component for the construction of spinning ducts; we further conclude that in both species chitin may indicate the evolutionary origin of...

  11. ANALISIS KUALITATIF KANDUNGAN SAKARIDA DALAM TEPUNG DAN PATI UMBI GANYONG (Canna edulis Ker.)

    OpenAIRE

    Aprilia Kusbandari

    2015-01-01

    Canna Tubers (Canna edulis Ker.) is one of the plants producing carbohydrates. Its also contains of protein, fat, vitamins, minerals, phosphorus, iron and more calciums. The purpose of this study is to identify of sugar in the powder and starch from canna tuber is a hydrolysis and didn’t hydrolysis. The method of qualitative analysis with tube test and Thin Layer Chromatography (TLC). The result indicated that before hydrolysis canna powder gave sucrose (Rf = 0.45) and mannose (Rf=0...

  12. Edible Film Making of Starch Canna Tuber (Canna Edulis Kerr) and Aplication to Packaging Galamai

    OpenAIRE

    Hafnimardiyanti Hafnimardiyanti; M.Ikhlas Armin; Martalius Martalius

    2014-01-01

    Canna (Canna edulis Kerr) was a tuber that had a high carbohydrate content so canna had excellent prospects to develop into edible film. The purpose of this study was to make edible film of canna starch, knowing storability galamai was packed with edible film and determine the level of preference panelists through organoleptic tests. In this research, manufacture of edible films with various concentrations of canna starch 2%, 3%, 4% and the use of plasticizer (glycerol) 1%, 2% and 3% with 100...

  13. Toxic effect of khat (Catha edulis) on memory: Systematic review and meta-analysis

    Science.gov (United States)

    Berihu, Birhane Alem; Asfeha, Gebrekidan Gebregzabher; Welderufael, Abadi Leul; Debeb, Yared Godefa; Zelelow, Yibrah Berhe; Beyene, Hafte Assefa

    2017-01-01

    Background: People use khat (Catha edulis) for its pleasant stimulant effect of physical activity, consciousness, motor, and mental functions. Although there are reports assessing the effect of khat on memory, there was no study based on formal systematic review and meta-analysis. Objective: We have therefore conducted this meta-analysis to determine the level of evidence for the effect of khat (C. edulis Forsk) on memory discrepancy. Methods: MEDLINE, Cochrane Library, PubMed, Academic Search Complete, SPORTDiscus, ScienceDirect, Scopus, Web of Science, and Google Scholar were searched to retrieve the papers for this review. Keywords utilized across database search were khat, cat, chat, long-term memory, short-term memory, memory deficit, randomized control trial, and cross-sectional survey. The search was limited to studies in humans and rodents; published in English language. Result: Finding of various studies included in our meta-analysis showed that the effect of acute, and subchronic exposure to khat showed that short-term memory appears to be affected depending on the duration of exposure. However, does not have any effect on long-term memory. Conclusion: Although a number of studies regarding the current topic are limited, the evidenced showed that khat (C. edulis) induced memory discrepancy. PMID:28149078

  14. Evaluation of physicochemical properties, proximate and nutritional composition of Gracilaria edulis collected from Palk Bay.

    Science.gov (United States)

    Sakthivel, Ravi; Pandima Devi, Kasi

    2015-05-01

    Gracilaria edulis, a red alga present in southeast coast of India was evaluated for its nutritional composition. FT-IR analysis of soluble polysaccharides revealed the presence of galactans, 3,6-anhydro-α-L-galactopyranose, sulphated galactose and the gelling agent agar, with the sulphate content estimated as 51.01 μg/mg of polysaccharide. Results of physicochemical properties and nutritional profile reveal the presence of dietary fibre (8.9 ± 0.62% DW), carbohydrate (101.61 ± 1.8 mg/g DW), crude protein (6.68 ± 0.94 mg/g DW) and lipid content (8.3 ± 1.03 mg/g DW). G. edulis contains biologically important fatty acids like palmitic acid (2.06%), linolenic acid (2.56%), and oleic acid (1.98%). The other nutritional components present in high amounts are proline, chlorophyll A and B, all the essential amino acids and vitamin A, E and C. These findings suggest that G. edulis has potent nutritional value which might be used as a source of nutrients for human and animals.

  15. Photocatalytic degradation of Congo red using Carissa edulis extract capped zinc oxide nanoparticles.

    Science.gov (United States)

    Fowsiya, J; Madhumitha, G; Al-Dhabi, Naif Abdullah; Arasu, Mariadhas Valan

    2016-09-01

    The use of plant extract to synthesize nanoparticle has been considered as one of the eco-friendly method. Additionally, it is a strong alternate for conventional methods which includes chemical and physical approach. In this study, microwave assisted extraction of Carissa edulis (C. edulis) at 70°C and 400W was used to extract the secondary metabolites. Further, the metabolites were used as capping agent and Zn (NO3)2 as the metal precursor to synthesize ZnO nanoparticles (ZnO NPs). UV-Vis spectroscopy, FT-IR, XRD, SEM and HR-TEM were used for the characterization of nanoparticles. The Surface Plasmon Resonance around 358nm from the UV-Vis spectroscopy result represents the ZnO NPs formation. The FT-IR confirms the presence of functional groups that acts as the capping agent for the synthesis of ZnO NPs. The crystalline structure of nanoparticles is revealed in the XRD result, morphology showed by SEM results and the size of the ZnO NPs were predicted by HR-TEM. We have carried out the photocatalytic degradation of Congo red at 365nm in photo reactor using ZnO NPs. The result from the photocatalytic degradation Congo red showed rate constant is (-k) 0.4947 with 97% of degradation. This is our first attempt on the C. edulis extract on ZnO NPs preparation and Congo red dye degradation revels that ZnO NPs exhibit good photocatalytic property.

  16. Applying design of experiments (DOE to flavonoid extraction from Passiflora alata and P. edulis

    Directory of Open Access Journals (Sweden)

    Peky Noriega

    2012-10-01

    Full Text Available The Passifloraceae family is extensively used in native Brazilian folk medicine to treat a wide variety of diseases. The problem of flavonoid extraction from Passiflora was treated by application of design of experiments (DOE, as an experiment with mixture including one categorical process variable. The components of the binary mixture were: ethanol (component A and water (component B; the categorical process variable: extraction method (factor C was varied at two levels: (+1 maceration and (-1 percolation. ANOVA suggested a cubic model for P. edulis extraction and a quadratic model for P. alata.These results indicate that the proportion of components A and B in the mixture is the main factor involved in significantly increasing flavonoid extraction. In regard to the extraction methods, no important differences were observed, which indicates that these two traditional extraction methods could be effectively used to extract flavonoids from both medicinal plants. The evaluation of antioxidant activity of the extract by ORAC method showed that P. edulis displays twice as much antioxidant activity as P. alata. Considering that maceration is a simple, rapid and environmentally friendly extraction method, in this study, the optimized conditions for flavonoid extraction from these Passiflora species is maceration with 75% ethanol for P. edulis and 50% ethanol for P. alata.

  17. Environmental influence on population dynamics of the bivalve Anomalocardia brasiliana

    Science.gov (United States)

    Corte, Guilherme Nascimento; Coleman, Ross A.; Amaral, A. Cecília Z.

    2017-03-01

    Understanding how species respond to the environment in terms of population attributes (e.g. abundance, growth, mortality, fecundity, and productivity) is essential to protect ecologically and economically important species. Nevertheless, responses of macrobenthic populations to environmental features are overlooked due to the need of consecutive samplings and time-consuming measurements. We examined the population dynamics of the filter-feeding bivalve Anomalocardia brasiliana on a tidal flat over the course of one year to investigate the hypothesis that, as accepted for macrobenthic communities, populations inhabiting environments with low hydrodynamic conditions such as tidal flat should have higher attributes than populations inhabiting more energetic habitats (i.e. areas more influenced by wave energy such as reflective and intermediate beaches). This would be expected because the harsh conditions of more energetic habitats force organisms to divert more energy towards maintenance, resulting in lower population attributes. We found that A. brasiliana showed moderate growth and secondary production at the study area. Moreover the recruitment period was restricted to a few months. A comparison with previous studies showed that, contrary to expected, A. brasiliana populations from areas with low hydrodynamic conditions have lower abundance, growth, recruitment and turnover rate. It is likely that morphodynamic characteristics recorded in these environments, such as larger periods of air exposure and lower water circulation, may affect food conditions for filter-feeding species and increase competition. In addition, these characteristics may negatively affect macrobenthic species by enhancing eutrophication processes and anoxia. Overall, our results suggest that models accepted and applied at the macrobenthic community level might not be directly extended to A. brasiliana populations.

  18. Seasonal variations of arsenic in mussels Mytilus galloprovincialis

    Science.gov (United States)

    Klarić, Sanja; Pavičić-Hamer, Dijana; Lucu, Čedomil

    2004-10-01

    Total arsenic concentration in the edible part of mussels Mytilus galloprovincialis was evaluated seasonally in the coastal area of Rijeka Bay (North Adriatic Sea, Croatia). Sampling stations were located close to the City of Bakar with no industrial facilities (site 1), in the vicinity of the oil refinery and oil thermoelectric power plant (Urinj, site 2), and 4 miles away from the Plomin coal thermoelectric power plant (Brseč village, site 3). Additionally, the concentration of arsenic in the tail muscle of the lobster Nephrops norvegicus, collected in Rijeka Bay, was studied. During winter at sites 2 and 3, the total arsenic in the edible part of the mussels was 16.4 mg As/kg FW (FW=fresh weight) and 4.38 mg As/kg FW, respectively, and increased during springtime at site 2 (6.5 mg As/kg FW) compared to the rest of the year, when individual total arsenic concentration at all sites ranged from 1.7 to 3.7 mg As/kg FW. In the winter (sites 2 and 3) and springtime (site 2) there was no correlation between the length of the mussel shell and the arsenic concentration in the edible part of the mussels. In the other seasons, at sites 1, 2 and 3, there was a correlation between arsenic in the edible part of mussels and shell length in most cases (correlation coefficients r varied from 0.64 to 0.85; P <0.05 to P <0.01). Correlation between shell length (in the narrow range of shell lengths from 3.4 to 5.0 cm) and arsenic in the edible part of the mussels shows linearity with a high regression coefficient (r =0.914; P <0.001). The increase of arsenic in the mussels during winter and spring was suggested at least partially as a result of a low nutritional status, i.e. reduced weight of the mussels' edible part during winter. In addition, a linear relationship was found between body length and arsenic concentration in the tail muscle (mean 17.11±4.48 mg As/kg FW) of the Norway lobster.

  19. A comparative study on the effects of barite, ilmenite and bentonite on four suspension feeding bivalves.

    Science.gov (United States)

    Strachan, Maia F; Kingston, Paul F

    2012-10-01

    The impact of drilling mud components on the filtration activity and survival of bivalve molluscs was investigated by exposing them to suspensions of 'standard' barite, finely milled barite, ilmenite and bentonite in sea water. Introduction of the components stimulated filtration activity in all four bivalves. In addition, the introduction of standard barite and ilmenite both had lethal effects, with none of the bivalves surviving the full duration of the experiments. In-vivo observations of the gill surfaces provided direct evidence of physical damage caused by the administration of barite and ilmenite. A marked difference between filtration activity and survival of animals dosed with 'standard' barite and 'fine' barite suggests that the observed effects were primarily caused by physical interference with gill function. The results also suggest that the use of fine barite in offshore drilling may provide a more favourable environmental impact profile than the use of ilmenite.

  20. Saturation-state sensitivity of marine bivalve larvae to ocean acidification

    Science.gov (United States)

    Waldbusser, George G.; Hales, Burke; Langdon, Chris J.; Haley, Brian A.; Schrader, Paul; Brunner, Elizabeth L.; Gray, Matthew W.; Miller, Cale A.; Gimenez, Iria

    2015-03-01

    Ocean acidification results in co-varying inorganic carbon system variables. Of these, an explicit focus on pH and organismal acid-base regulation has failed to distinguish the mechanism of failure in highly sensitive bivalve larvae. With unique chemical manipulations of seawater we show definitively that larval shell development and growth are dependent on seawater saturation state, and not on carbon dioxide partial pressure or pH. Although other physiological processes are affected by pH, mineral saturation state thresholds will be crossed decades to centuries ahead of pH thresholds owing to nonlinear changes in the carbonate system variables as carbon dioxide is added. Our findings were repeatable for two species of bivalve larvae could resolve discrepancies in experimental results, are consistent with a previous model of ocean acidification impacts due to rapid calcification in bivalve larvae, and suggest a fundamental ocean acidification bottleneck at early life-history for some marine keystone species.

  1. Arsenic and trace metals in commercially important bivalves, Anadara granosa and Paphia undulata

    Energy Technology Data Exchange (ETDEWEB)

    Mat, I. (Univ. of Malaya, Kuala Lumpur (Malaysia))

    1994-06-01

    The semi-culture of marine bivalves particularly Anadara granosa is of considerable economic importance in Malaysia. Currently, about 4-5000 ha of mudflats along the west coast are utilized for this purpose. Therefore, contamination of the highly productive mudflats with heavy metals tend to be accumulated in the filter feeding organisms such as bivalve molluscs which often serve as important environmental sinks of heavy metals. Bivalve molluscs, A. granosa and Paphia undulata are commercially important seafoods and popular among the locals in Malaysia. With this point in mind, it is intended to evaluate the concentration levels of arsenic as well as trace metals (Co, Cu, Ni, Cd, Zn, Cr and Pb) in both species derived from retail outlets in the city of Kuala Lumpur. Although this analysis may not indicate the site of capture but may act as a direct check on the contamination of seafoods available to the consumers. 17 refs., 2 tabs.

  2. Approaches for evaluating the effects of bivalve filter feeding on nutrient dynamics in Puget Sound, Washington

    Science.gov (United States)

    Konrad, Christopher P.

    2014-01-01

    Marine bivalves such as clams, mussels, and oysters are an important component of the food web, which influence nutrient dynamics and water quality in many estuaries. The role of bivalves in nutrient dynamics and, particularly, the contribution of commercial shellfish activities, are not well understood in Puget Sound, Washington. Numerous approaches have been used in other estuaries to quantify the effects of bivalves on nutrient dynamics, ranging from simple nutrient budgeting to sophisticated numerical models that account for tidal circulation, bioenergetic fluxes through food webs, and biochemical transformations in the water column and sediment. For nutrient management in Puget Sound, it might be possible to integrate basic biophysical indicators (residence time, phytoplankton growth rates, and clearance rates of filter feeders) as a screening tool to identify places where nutrient dynamics and water quality are likely to be sensitive to shellfish density and, then, apply more sophisticated methods involving in-situ measurements and simulation models to quantify those dynamics.

  3. Pathogenic marine microbes influence the effects of climate change on a commercially important tropical bivalve.

    Science.gov (United States)

    Turner, Lucy M; Alsterberg, Christian; Turner, Andrew D; Girisha, S K; Rai, Ashwin; Havenhand, Jonathan N; Venugopal, M N; Karunasagar, Indrani; Godhe, Anna

    2016-01-01

    There is growing evidence that climate change will increase the prevalence of toxic algae and harmful bacteria, which can accumulate in marine bivalves. However, we know little about any possible interactions between exposure to these microorganisms and the effects of climate change on bivalve health, or about how this may affect the bivalve toxin-pathogen load. In mesocosm experiments, mussels, Perna viridis, were subjected to simulated climate change (warming and/or hyposalinity) and exposed to harmful bacteria and/or toxin-producing dinoflagellates. We found significant interactions between climate change and these microbes on metabolic and/or immunobiological function and toxin-pathogen load in mussels. Surprisingly, however, these effects were virtually eliminated when mussels were exposed to both harmful microorganisms simultaneously. This study is the first to examine the effects of climate change on determining mussel toxin-pathogen load in an ecologically relevant, multi-trophic context. The results may have considerable implications for seafood safety.

  4. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    NARCIS (Netherlands)

    Filgueira, R.; Byron, C.J.; Comeau, L.A.; Jansen, H.M.; Smaal, A.C.

    2015-01-01

    The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities,

  5. Facilitation on an intertidal mudflat : the effect of siphon nipping by flatfish on burying depth of the bivalve Macoma balthica

    NARCIS (Netherlands)

    de Goeij, P; Luttikhuizen, PC; van der Meer, J; Piersma, T

    2001-01-01

    During deposit feeding on benthic microalgae, the siphon of buried tellinid bivalves like Macoma balthica is vulnerable to nipping by plaice Pleuronectes platessa and other flatfish. We experimentally tested the hypothesis that siphon nippers facilitate predation on the entire bivalve (by shorebirds

  6. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    DEFF Research Database (Denmark)

    Filgueira, Ramón; Byron, C.J.; Comeau, L.A.;

    2015-01-01

    The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densitie...

  7. A Darriwilian (Middle Ordovician bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

    Directory of Open Access Journals (Sweden)

    Kristian G. Jakobsen

    2016-12-01

    Full Text Available A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of the molluscs comprise bivalves, especially nuculoids, which were biogeographically restricted to low latitudes during the Ordovician. The molluscan assemblage displays a very high degree of endemism at species level, though the bivalve Sthenodonta eastii also occurs in the Georgina Basin farther to the northeast. This indicates a possible marine connective seaway between the Georgina and Amadeus basins during the Darriwilian. Nuculites, Cyrtodonta, and Modiolopsis are cosmopolitan and previously reported from North China, Avalonia, and Southern Gondwana.

  8. Physiological responses of two seaweed biofilter candidates, Gracilariopsis bailiniae Zhang et Xia and Hydropuntia edulis (S Gmelin, to nutrient source and environmental factors

    Directory of Open Access Journals (Sweden)

    Rhea Joy Carton

    2011-12-01

    Full Text Available Two gracilarioid species, Gracilariopsis bailiniae and Hydropuntia edulis, were comparedbased on their growth under different temperature and salinity levels and nitrogen source and on theirphotosynthetic responses under different irradiance levels. Results show that growth of Gp. bailiniaewas significantly higher than that of H. edulis. Both species were euryhaline and had optimum growthrates at 27˚C (16.06 % d-1 ± 0.10 for Gp. bailiniae and 9.53 % d-1 ± 0.62 for H. edulis under bothammonium and nitrate enrichment. Gracilariopsis bailiniae was able to use both N-forms as a nitrogensource in all temperature and salinity levels tested. Meanwhile, the interactive effect of nitrogensource with temperature was observed for H. edulis with plants grown in nitrate enrichment showingsignificantly higher growth rates than those in ammonium. Nitrate enrichment also resulted to highergrowth rates for H. edulis in all salinity levels tested. Photosynthetic rates of Gp. bailiniae were higherthan H. edulis. We also found a two-fold difference between the maximum photosynthetic rate (Pmaxof Gp. bailiniae (12.41 ± 1.81 and that of H. edulis (6.44 ± 0.62. However, photosynthetic efficiency(α was significantly higher in H. edulis than in Gp. bailiniae while compensation and saturation pointirradiance levels were similar in both species.

  9. Heavy metals in bivalves collected from river estuaries of Thailand. [Perna viridis

    Energy Technology Data Exchange (ETDEWEB)

    Menasveta, P.; Cheevapora, V.; Wongwit, C.

    1984-01-01

    This investigation was undertaken to determine the levels of lead, zinc, copper, cadmium, and mercury in five species of bivalves collected from six river estuaries of Thailand during July 1978 to January 1979. The in situ bioassay for studying heavy metals uptake by green mussels (Perna viridis) was also conducted at the Chao Phraya river estuary during February 1980 to March 1981. The results revealed high contamination of lead in mussels during the period of river run-off. The factors that might contribute to this incidence were discussed. Contaminations of the other four metals in bivalves did not show great variation and they were still within the acceptable limits.

  10. 九种现代双壳类壳体物相组成的对比研究%Comparison Study on the Shell Mineralogy of 9 Species of Modern Bivalves Living in Yellow Sea

    Institute of Scientific and Technical Information of China (English)

    范德江; 刘升发; 张爱滨; 于子山; 王文正

    2005-01-01

    利用X射线衍射分析技术,对黄东海常见的9种现代双壳类壳体进行了物相分析,结果表明这些双壳类壳体分别属于三种类型,即文石质壳、方解石质壳、文石+方解石混合质壳.其中,菲律宾蛤仔(Ruditapes philippinarum)、中国蛤蜊(Mactra chinensis)、四角蛤蜊(Mactra veneriformis)、薄片镜蛤(Dosinia laminata)、毛蚶(Scapharca subcrenuzta)属于文石质壳,长牡蛎(Crassostrea gigas)、中国不等蛤(Anomia chinensis)、海湾扇贝(Argopecten irradieus)属于方解石质壳,紫贻贝(Mytilus edulis)属于文石+方解石质的混合质壳;双壳类壳体物相组成与其生活方式有着一定的联系,营底栖埋入式生活者趋于形成文石质壳,底栖固着生活方式者趋于形成方解石质壳或混合质壳;不同大小的菲律宾蛤仔(Ruditapes philippinarum)的物相组成上几乎没有差别,表明其壳体物相组成不受生命效应的影响.

  11. Molecular phylogenetics of genus Mytilus based on the 16S rRNA sequences%基于16S rRNA序列初步探讨贻贝属的系统发育

    Institute of Scientific and Technical Information of China (English)

    沈玉帮; 李家乐; 牟月军

    2009-01-01

    通过比较贻贝属5个物种包括中国的两种贻贝的线粒体16S rRNA基因部分序列,来初步确定它们的系统发育关系和了解中国沿海两种贻贝的遗传多样性情况.以Perna viridis为外群,采用NJ法和MP法构建分子系统树.系统发育分析表明,5种贻贝(Mytilus californianus, M. corcuscus, M. galloprovincialis, M. edulis, M. trossulus)在系统树上依次进行分叉,呈放射状.M. californianus最为原始,M. corcuscus次之.每一个贻贝物种都形成单系.其中,M. edulis和M. trossulus是非常相似的,M. corcuscus和M. californianus的亲缘关系近.同时发现,我国沿海分布的紫贻贝(M. galloprovincialis)和厚壳贻贝(M. corcuscus)的遗传多样性都较高,但厚壳贻贝的遗传多样性要低于紫贻贝,可能是由于厚壳贻贝过度被渔民开采等导致厚壳贻贝群体大小降低的缘故.这里系统发育分析为将来进行物种进化、迁移和育种方面的比较研究提供理论基础.

  12. Detection of Arcobacter spp. in Mytilus galloprovincialis samples collected from Apulia region

    Directory of Open Access Journals (Sweden)

    Elisabetta Bonerba

    2015-02-01

    Full Text Available The aim of the study was to evaluate the occurrence of Arcobacter spp. in 20 samples of Mytilus galloprovincialis purchased at fish markets in Apulia region. The detection of Arcobacter spp. was performed, after selective enrichment, on modified charcoal cefoperazone deoxycholate (mCCD agar supplemented with Cefoperazone, Amphotericin B and Teicoplanin (CAT. In 6 out of the 20 tested samples the presence of Arcobacter spp. was found and confirmed by genus-based polymerase chain reaction. All the isolates were identified as belonging to the species Arcobacter butzleri using 16S rDNA sequencing and BLAST online. The results represent the first report in Italy of A. butzleri detection in marketed Mytilus galloprovincialis. The survey underlines the epidemiological importance of A. butzleri as an emerging pathogen, and highlights that mussels should be considered as a potential cause of foodborne disease outbreak.

  13. THE PHENOTYPIC STRUCTURE OF A MYTILUS GALLOPROVINCIALIS LMK POPULATION FROM THE ROMANIAN BLACK SEA SHORE

    Directory of Open Access Journals (Sweden)

    Aliona Novac

    2006-08-01

    Full Text Available : Among the specimens of Mytilus galloprovincialis Lmk. from the Black Sea, function of the color of the ostracum (brown, dark blue or brown with blue stripes, one can differentiate several forms. These colors are genetically determined (Stolbova, Pirkova, Ladyghina, 1996; Scherban, 2000; Shurova, 2001. The present paper analyzes the situation of these phenotypic groups, using specimens sampled at different depths in the area of Agigea dike.

  14. Mathematical modeling of the growth and development of the mussel Mytilus galloprovincialis on artificial substrates

    Science.gov (United States)

    Vasechkina, E. F.; Kazankova, I. I.

    2014-11-01

    A mathematical model simulating the growth and development of the mussel Mytilus galloprovincialis Lam. on artificial substrates has been constructed. The model is based on experimental data and contains mathematical descriptions of the filtration, respiration, excretion, spawning, and growth of an individual during its ontogenesis from the moment it attaches to a solid substrate to the attainment of a marketable size. The test computations have been compared to the available observation data for mussel farms.

  15. Comparative Analysis of Gender-Associated Complete Mitochondrial Genomes in Marine Mussels (Mytilus spp.)

    OpenAIRE

    Breton, Sophie; Burger, Gertraud; Stewart, Donald T.; Blier, Pierre U.

    2006-01-01

    Marine mussels of the genus Mytilus have an unusual mode of mitochondrial DNA (mtDNA) transmission termed doubly uniparental inheritance (DUI). Female mussels are homoplasmic for the F mitotype, which is inherited maternally, while males are usually heteroplasmic, carrying a mixture of the maternal F mitotype and the paternally inherited M genome. Two classes of M genomes have been observed: “standard” M genomes and “recently masculinized” M genomes. The latter are more similar to F genomes a...

  16. Shell growth and environmental control of methanophyllic Thyasirid bivalves from Svalbard cold seeps

    Science.gov (United States)

    Carroll, Michael; Åström, Emmelie; Ambrose, William; Locke, William; Oliver, Graham; Hong, Wei-Li; Carroll, JoLynn

    2016-04-01

    The analysis of molluscan shell material (sclerochronology) can provide information about an organism's age, growth history, and environmental conditions during its lifetime. Bivalve molluscs are common members of hydrothermal vents and methane cold seeps communities where, supported by chemosynthetic symbionts, they can reach high density and biomass. But little is known about methane-associated bivalve populations inhabiting high-Arctic cold seeps, and sclerochronological analysis of methane-influenced bivalves is rare. We measured growth rates and elemental and isotopic shell signatures in a newly discovered species of bivalve (Thyasiridae) from cold seeps at 350-390m depth southwest of Svalbard. First discovered in 2014, recently described shells of Thyasira capitanea sp.nov. were found at 2 independent seep systems in Storfjordrenna. Mean shell carbon isotopic ratios from inorganic δ13C (mean = -4.8‰) and organic δ13C (mean = -26.9‰) fractions clearly indicate a methane influenced habitat and food source for these organisms. Shell mineral ratios (Li/Ca, Mg/Ca, Mn/Ca, Fe/Ca, Sr/Ca, Ba/Ca, Pb/Ca) sampled along the axis of growth with laser-ablated ICP-MS exhibit variability through time and between sites, suggesting that concentrations of these elements that may be affected by methane emissions. The mineralogical data also elucidates the internal pattern of shell deposition and growth checks, and combined with the isotopic and growth rate data, enables us to interpret the temporal history of methane release from these locations.

  17. Bivalve aquaculture transfers in Atlantic Europe. Part A: Transfer activities and legal framework

    DEFF Research Database (Denmark)

    Muehlbauer, F.; Fraser, D.; Brenner, M.

    2014-01-01

    Intentional transfers of numerous bivalve species have had a long tradition and are commonly conducted along the European Atlantic coast. However numerous studies have concluded that intentional transfer of species for aquaculture purposes is one of the most principal vectors for the introduction...

  18. Validation and comparison of methods for enumeration of faecal coliforms and Escherichia coli in bivalve molluscs

    NARCIS (Netherlands)

    Mooijman KA; Poelman M; Stegeman H; Warmerdam C; Teunis PFM; Roda Husman AM de; RIKILT; MGB

    2007-01-01

    The main result of the validation study to show the equivalence of two methods for the enumeration of faecal coliforms in bivalve molluscs is that the plate count method on Mac Conkey agar was indeed found to be equivalent to the MPN method. Meaning that the Netherlands fulfilled the demands as stat

  19. A predatory bivalved euarthropod from the Cambrian (Stage 3) Xiaoshiba Lagerstätte, South China

    Science.gov (United States)

    Yang, Jie; Ortega-Hernández, Javier; Lan, Tian; Hou, Jin-Bo; Zhang, Xi-Guang

    2016-06-01

    Bivalved euarthropods represent a conspicuous component of exceptionally-preserved fossil biotas throughout the Lower Palaeozoic. However, most of these taxa are known from isolated valves, and thus there is a limited understanding of their morphological organization and palaeoecology in the context of early animal-dominated communities. The bivalved euarthropod Clypecaris serrata sp. nov., recovered from the Cambrian (Stage 3) Hongjingshao Formation in Kunming, southern China, is characterized by having a robust first pair of raptorial appendages that bear well-developed ventral-facing spines, paired dorsal spines on the trunk, and posteriorly oriented serrations on the anteroventral margins of both valves. The raptorial limbs of C. serrata were adapted for grasping prey employing a descending stroke for transporting it close the mouth, whereas the backwards-facing marginal serrations of the bivalved carapace may have helped to secure the food items during feeding. The new taxon offers novel insights on the morphology of the enigmatic genus Clypecaris, and indicates that the possession of paired dorsal spines is a diagnostic trait of the Family Clypecarididae within upper stem-group Euarthropoda. C. serrata evinces functional adaptations for an active predatory lifestyle within the context of Cambrian bivalved euarthropods, and contributes towards the better understanding of feeding diversity in early ecosystems.

  20. Burrowing Behavior of a Deposit Feeding Bivalve Predicts Change in Intertidal Ecosystem State

    NARCIS (Netherlands)

    Compton, T.J.; Bodnar, W.; Koolhaas, A.; Dekinga, A.; Holthuijsen, S.; Ten Horn, J.; McSweeney, N.; van Gils, J.A.; Piersma, T,

    2016-01-01

    Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

  1. Burrowing behavior of a deposit feeding bivalve predicts change in intertidal ecosystem state

    NARCIS (Netherlands)

    Compton, Tanya J.; Bodnar, Wanda; Koolhaas, Anita; Dekinga, Anne; Holthuijsen, Sander; ten Horn, Job; McSweeney, Niamh; van Gils, Jan; Piersma, Theunis

    2016-01-01

    Behavior has a predictive power that is often underutilized as a tool for signaling ecological change. The burrowing behavior of the deposit feeding bivalve Macoma balthica reflects a typical food-safety trade-off. The choice to live close to the sediment surface comes at a risk of predation and is

  2. Bivalve grazing, nutrient cycling and phytoplankton dynamics in an estuarine ecosystem.

    NARCIS (Netherlands)

    Prins, T.C.

    1996-01-01

    This thesis has considered the impact of the suspension feeding bivalve Mytilusedulis on nutrient cycling and phytoplankton in an estuarine ecosystem. The research was started within the framework of an extensive research project with the objective to evaluate the changes in the Oosterschelde ecosys

  3. Temperature dependent larval occurrence and spat settlement of the invasive brackish water bivalve

    NARCIS (Netherlands)

    van der Gaag, M.; van der Velde, G.; Wijnhoven, S.; Rajagopal, S.

    2014-01-01

    Mytilopsis leucophaeata, an invasive bivalve species, causes fouling problems by settling on submerged constructions and in cooling water circuits in brackish water. To predict spat fall we studied the larval occurrence and settlement of this species in the brackish Noordzeekanaal canal in the Nethe

  4. Novas ocorrências de gastrópodes e bivalves marinhos no Brasil (Mollusca

    Directory of Open Access Journals (Sweden)

    Absalão Ricardo Silva

    2003-01-01

    Full Text Available The gastropods Costaclis egregia (Dall, 1889, Thaleia nisonis (Dall, 1889, Tjaernoeia michaeli Engl, 2001 and the bivalves Bathyarca sp., Myonera aff. ruginosa (Jeffreys, 1882 are recorded for the first time in Brazilian waters. This paper presents a brief description of these species and also include ilustrations.

  5. Fossil predation: did some clavilithine fasciolariid gastropods employ valve-wedging to feed on bivalves?

    NARCIS (Netherlands)

    Vermeij, Geerat J.

    2015-01-01

    Several gastropods, including members of the Busyconinae, wedge or chip bivalve prey by inserting the outer lip between the valves. This habit, which is associated with an abapically downwardly convex outer lip, often results in breakage and subsequent repair of the lip. I tested the hypothesis that

  6. Mosaic haploid-diploid embryos and polyspermy in the tellinid bivalve Macoma balthica

    NARCIS (Netherlands)

    Luttikhuizen, PC; Pijnacker, LP

    2002-01-01

    We investigated meiosis, fertilization, and early development in eggs of the tellinid bivalve Macoma balthica (L.), which has external fertilization. Meiosis is standard but polyspermy is found to be very common. In all eight crosses examined, mosaic embryos consisting of a mixture of diploid (2n =

  7. Nutritional and reproductive strategies in a chemsoymbiotic bivalve living in a tropical intertidal seagrass bed

    NARCIS (Netherlands)

    van der Geest, Matthijs; Sall, Amadou Abderahmane; Ely, SIdi Ould; Nauta, Reindert W.; Gils, Jan A. van; Piersma, Theunis

    2014-01-01

    Sulphide-oxidizing endosymbiont-bearing bivalves often dominate the infauna of seagrass-covered sediments, where they control sulphide levels and contribute to carbon cycling by feeding on chemosynthetically fixed carbon and suspended particulate organic matter (SPOM). Previous studies from temperat

  8. Nutritional and reproductive strategies in a chemosymbiotic bivalve living in a tropical intertidal seagrass bed

    NARCIS (Netherlands)

    van der Geest, M.; Sall, A.A.; Ely, S.O.; Nauta, R.W.; van Gils, J.A.; Piersma, T.

    2014-01-01

    Sulphide-oxidizing endosymbiont-bearing bivalves often dominate the infauna of seagrass-covered sediments, where they control sulphide levels and contribute to carbon cycling by feeding on chemosynthetically fixed carbon and suspended particulate organic matter (SPOM). Previous studies from temperat

  9. A molecular phylogeny of bivalve mollusks: ancient radiations and divergences as revealed by mitochondrial genes.

    Directory of Open Access Journals (Sweden)

    Federico Plazzi

    Full Text Available BACKGROUND: Bivalves are very ancient and successful conchiferan mollusks (both in terms of species number and geographical distribution. Despite their importance in marine biota, their deep phylogenetic relationships were scarcely investigated from a molecular perspective, whereas much valuable work has been done on taxonomy, as well as phylogeny, of lower taxa. METHODOLOGY/PRINCIPAL FINDINGS: Here we present a class-level bivalve phylogeny with a broad sample of 122 ingroup taxa, using four mitochondrial markers (MT-RNR1, MT-RNR2, MT-CO1, MT-CYB. Rigorous techniques have been exploited to set up the dataset, analyze phylogenetic signal, and infer a single final tree. In this study, we show the basal position of Opponobranchia to all Autobranchia, as well as of Palaeoheterodonta to the remaining Autobranchia, which we here propose to call Amarsipobranchia. Anomalodesmata were retrieved as monophyletic and basal to (Heterodonta + Pteriomorphia. CONCLUSIONS/SIGNIFICANCE: Bivalve morphological characters were traced onto the phylogenetic trees obtained from the molecular analysis; our analysis suggests that eulamellibranch gills and heterodont hinge are ancestral characters for all Autobranchia. This conclusion would entail a re-evaluation of bivalve symplesiomorphies.

  10. In situ method for measurements of community clearance rate on shallow water bivalve populations

    DEFF Research Database (Denmark)

    Hansen, Benni W.; Dolmer, Per; Vismann, Bent

    2011-01-01

    with an air lift connected to a SCUBA diver pressure tank generating a continuous and gentle water circulation. This ensures a complete mixture of suspended particles, and thereby, a maximum filtration by the bivalves. An in situ fluorometer was mounted to record plant pigment reduction due to mussel...

  11. Draft Genome Sequence of the Emerging Bivalve Pathogen Vibrio tubiashii subsp. europaeus.

    Science.gov (United States)

    Spinard, Edward J; Dubert, Javier; Nelson, David R; Gomez-Chiarri, Marta; Barja, Juan L

    2016-07-28

    Vibrio tubiashii subsp. europaeus is a bivalve pathogen isolated during episodes of mortality affecting larval cultures in different shellfish hatcheries. Here, we announce the draft genome sequence of the type strain PP-638 and describe potential virulence factors, which may provide insight into the mechanism of pathogenicity.

  12. Modiolarca lateralis (Pteryomorphia: Mytilidae: bivalve associated to six species of ascidians from Bocas del Toro, Panama

    Directory of Open Access Journals (Sweden)

    Juan I Cañete

    2013-11-01

    Full Text Available We describe the presence of the bivalve Modiolarca lateralis (Say, 1822 in six tropical ascidians Ascidia curvata, A. sydneiensis, A. panamensis, A. interrupta, Herdmania pallida and Polycarpa spongiabilis collected at depths of 1-3 m on coral reefs, mangrove roots and dock supports in Almirante Bay, Bocas del Toro, Panama (9°18'N, 82°13'W during June-July 2011. Bivalve prevalence varied between 9-30% across species, but was mainly associated with A. panamensis, P. spongiabilis and A. interrupta. Prevalence seems to be influenced by tunic thickness rather than by the ascidian size. Bivalves varied in size (0.6-11 mm shell length, with the smallest individual found in A. sydneiensis. There were only one or two bivalves per ascidians, although a maximum of 18 was found in one A. panamensis. M. lateralis seems to behave similarly to its temperate counterparts: it has a variety of hosts, occurs mainly in the anterior region of the ascidians, and has a variable abundance per host.

  13. 76 FR 65200 - Risk Assessment on Norovirus in Bivalve Molluscan Shellfish: Request for Comments and for...

    Science.gov (United States)

    2011-10-20

    ... preventive practices and controls, food preparation and consumption practices, and the relationship between... thousands of cases in Canada annually (Refs. 2 to 4). The viruses can be transmitted through consumption of... consumption have been traced to contamination during growth and harvest (Refs. 1 and 6). Bivalve...

  14. Freshwater bivalve mollusca (unionidae, sphaeriidae, corbiculidae) of the Savannah River Plant, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Britton, J.C.; Fuller, S.L.H.

    1980-11-01

    A guide to freshwater bivalve molluscs found at the Savannah River Plant is presented. A dichotomous taxonomic key is provided to common forms and to unreported species whose geographic distributions include nearby localities. Discussions of ecology, life history, larval hosts, and other pertinent information is provided. (ACR)

  15. Monobrachium parasitum (Cnidaria: Hydrozoa) epizoic on antarctic bivalves and its bipolarity

    NARCIS (Netherlands)

    Jarms, G.; Mühlenhardt-Siegel, U.

    1998-01-01

    During antarctic macrozoobenthos research, colonies of Monobrachium were found on small bivalves. The species problem of the genus Monobrachium is discussed and it is stated that there are three species. However, the widespread species Monobrachium parasitum might be a species-complex comprising sev

  16. Immunocytotoxicity, cytogenotoxicity and genotoxicity of cadmium-based quantum dots in the marine mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Rocha, Thiago Lopes; Gomes, Tânia; Cardoso, Cátia; Letendre, Julie; Pinheiro, José Paulo; Sousa, Vânia Serrão; Teixeira, Margarida Ribau; Bebianno, Maria João

    2014-10-01

    There is an increased use of Quantum Dot (QDs) in biological and biomedical applications, but little is known about their marine ecotoxicology. So, the aim of this study was to investigate the possible immunocytotoxic, cytogenotoxic and genotoxic effects of cadmium telluride QDs (CdTe QDs) on the marine mussel Mytilus galloprovincialis. Mussels were exposed to 10 μg L(-1) of CdTe QDs or to soluble Cd [Cd(NO3)2] for 14 days and Cd accumulation, immunocytotoxicity [hemocyte density, cell viability, lysosomal membrane stability (LMS), differential cell counts (DCC)], cytogenotoxicity (micronucleus test and nuclear abnormalities assay) and genotoxicity (comet assay) were analyzed. Results show that in vivo exposure to QDs, Cd is accumulated in mussel soft tissues and hemolymph and induce immunotoxic effects mediated by a decrease in LMS, changes in DCC, as well as genotoxicity (DNA damage). However, QDs do not induce significant changes in hemocytes density, cell viability and cytogenetic parameters in opposition to Cd(2+). Soluble Cd is the most cytotoxic and cytogenotoxic form on Mytilus hemocytes due to a higher accumulation of Cd in tissues. Results indicate that immunotoxicity and genotoxicity of CdTe QDs and Cd(2+) are mediated by different modes of action and show that Mytilus hemocytes are important targets for in vivo QDs toxicity.

  17. Analysis of Passion Fruit rinds (Passiflora edulis): Isoorientin quantification by hptlc and evaluation of antioxidant (radical scavenging) capacity

    OpenAIRE

    Maria Luiza Zeraik; Yariwake,Janete H.; Jean-Noël Wauters; Monique Tits; Luc Angenot

    2012-01-01

    The content of isoorientin in passion fruit rinds (Passiflora edulis fo. flavicarpa O. Degener) was determined by HPTLC (high performance thin layer chromatography) with densitometric analysis. The results revealed a higher amount of isoorientin in healthy rinds of P. edulis (92.275 ± 0.610 mg L-1) than in rinds with typical symptoms of PWV (Passion fruit Woodiness Virus) infection (28.931 ± 0.346 mg L-1). The HPTLC data, allied to assays of radical scavenging activity, suggest the potential ...

  18. Morphoanatomic aspects and phytochemical screening of Plinia edulis (Vell. Sobral (Myrtaceae Aspectos morfoanatômicos e triagem fitoquímica de Plinia edulis (Vell. Sobral (Myrtaceae

    Directory of Open Access Journals (Sweden)

    Tati Ishikawa

    2008-09-01

    Full Text Available Plinia edulis (Myrtaceae, popularly known as "cambucá", is a Brazilian medicinal plant employed in the treatment of stomach problems and throat affections by the "caiçaras", fishermen of coastal localities. Aiming to contribute with the species knowledge the leaves of P. edulis were analyzed macro and microscopically and the chemical composition of the volatile oil was determined using a combination of GC/MS and retention indices. The antimicrobial assay and the phytochemical screening of the aqueous ethanol extract of the leaves have been performed to correlate the secondary metabolites and the traditional use. Leaves present morphological characteristics of others Myrtaceae species and some particularities, such as the circular idioblasts in number of 2 to 4, scattered perpendicularly at the adaxial surface, with druses or prismatic crystals. In the volatile oil fifteen components have been identified, of which epi-α-cadinol (21.7%, α-cadinol (20.2% and trans-caryophyllene (14.2% were major. The phytochemical screening of the aqueous ethanol extract showed the presence of substances with pharmacological interest, such as flavonoids, tannins, saponins and terpenoids but, despite of the presence of these classes, the extract did not inhibit the growth of Aspergillus niger, Candida albicans, Escherichia coli and Staphylococcus aureus in a concentration of 1,000 mg/mL.Plinia edulis (Myrtaceae, popularmente conhecida como "cambucá", é uma planta medicinal nativa do Brasil e empregada no tratamento de problemas estomacais e afecções de garganta por populações caiçaras. Buscando contribuir para o conhecimento da espécie, as folhas de P. edulis foram caracterizadas macro e microscopicamente e a composição química do óleo volátil foi determinada usando uma combinação de CG/EM e índices de retenção. O extrato hidroetanólico das folhas foi avaliado quanto ao perfil fitoquímico e à atividade antimicrobiana procurando-se a correla

  19. Boletus edulis biologically active biopolymers induce cell cycle arrest in human colon adenocarcinoma cells.

    Science.gov (United States)

    Lemieszek, Marta Kinga; Cardoso, Claudia; Ferreira Milheiro Nunes, Fernando Hermínio; Ramos Novo Amorim de Barros, Ana Isabel; Marques, Guilhermina; Pożarowski, Piotr; Rzeski, Wojciech

    2013-04-25

    The use of biologically active compounds isolated from edible mushrooms against cancer raises global interest. Anticancer properties are mainly attributed to biopolymers including mainly polysaccharides, polysaccharopeptides, polysaccharide proteins, glycoproteins and proteins. In spite of the fact that Boletus edulis is one of the widely occurring and most consumed edible mushrooms, antitumor biopolymers isolated from it have not been exactly defined and studied so far. The present study is an attempt to extend this knowledge on molecular mechanisms of their anticancer action. The mushroom biopolymers (polysaccharides and glycoproteins) were extracted with hot water and purified by anion-exchange chromatography. The antiproliferative activity in human colon adenocarcinoma cells (LS180) was screened by means of MTT and BrdU assays. At the same time fractions' cytotoxicity was examined on the human colon epithelial cells (CCD 841 CoTr) by means of the LDH assay. Flow cytometry and Western blotting were applied to cell cycle analysis and protein expression involved in anticancer activity of the selected biopolymer fraction. In vitro studies have shown that fractions isolated from Boletus edulis were not toxic against normal colon epithelial cells and in the same concentration range elicited a very prominent antiproliferative effect in colon cancer cells. The best results were obtained in the case of the fraction designated as BE3. The tested compound inhibited cancer cell proliferation which was accompanied by cell cycle arrest in the G0/G1-phase. Growth inhibition was associated with modulation of the p16/cyclin D1/CDK4-6/pRb pathway, an aberration of which is a critical step in the development of many human cancers including colon cancer. Our results indicate that a biopolymer BE3 from Boletus edulis possesses anticancer potential and may provide a new therapeutic/preventive option in colon cancer chemoprevention.

  20. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Science.gov (United States)

    Duperron, S.; Gaudron, S. M.; Rodrigues, C. F.; Cunha, M. R.; Decker, C.; Olu, K.

    2013-05-01

    Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae). Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  1. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2012-11-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria which ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, East America, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous more easily accessible shallow marine species were studied. We here provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to Marmara Sea, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 51 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae, and compared among families with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions, yet relatively little is known regarding their diversity and functioning apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on Oceans, we advocate for a better assessment of bivalve symbioses diversity in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change

  2. How predictable is high bivalve recruitment in the Wadden Sea after a severe winter?

    Science.gov (United States)

    Strasser, Matthias; Dekker, Rob; Essink, Karel; Günther, Carmen-Pia; Jaklin, Sandra; Kröncke, Ingrid; Madsen, Poul Brinch; Michaelis, Hermann; Vedel, Grace

    2003-02-01

    Higher than average recruitment among bivalves on the intertidal flats of the Wadden Sea was often observed after severe winters in the period 1940-1995. The occurrence of another severe winter in 1995/96 prompted us to test the hypothesis of severe winters leading to universally high bivalve recruitment on a large geographic scale (500 km coastline) in temperate shallow waters. We analysed data sets on bivalve abundance from seven areas in the Dutch, German and Danish Wadden Sea. The longer data sets showed generally higher bivalve recruitment in the 1970s and 1980s than in the 1990s which may be related to the near absence of severe winters since 1987. Considering the period 1988 onwards (the longest possible period in which 1995/96 was the only severe winter), recruitment of Cerastoderma edule was in 1996 - in agreement with our hypothesis - above average in all seven areas investigated. In contrast, recruitment of Macoma balthica and Mya arenaria was for the same period above average only in the southern Wadden Sea (south-west of Jade Bay) but not in the northern Wadden Sea (north of Eiderstedt peninsula). These regional differences may be related to (i) the different topography of the northern Wadden Sea (with barrier islands west of the mainland) compared to the southern Wadden Sea (with barrier islands north of the mainland) and subsequent differential effects of wind-induced currents on bivalve recruitment, (ii) differences in biotic factors such as standing stocks, larval supply or epibenthic predation or (iii) changes in environmental conditions. Our results demonstrate that large-scale comparisons along coasts are an indispensable addition to insights derived from local studies alone.

  3. First records of Freshwater Bivalves of Ilha Grande National Park, Paraná, Brazil

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    Flávio Henrique Ragonha

    2014-03-01

    Full Text Available The Ilha Grande National Park, Paraná, Brazil, is located in the Upper Paraná River and has characteristics typical of a floodplains. This protected area includes lagoons connected and disconnected to the Paraná River, although the latter also connect during periods of high water level, thus composing a heterogeneous group of lacustrine environments. The enormous potential the flora and fauna diversities are still little known to the region, as can be seen through benthic invertebrates, inclunding bivalves mollusks. The granulometric composition of these floodplain lagoons was formed mainly by mud and very fine sand. Furthermore, organic matter composition was predominantly of fine particulate. The other abiotic factors differed from lagoons located within the island of the park to those located in the left margin of Paraná River. The results demonstrated the importance of abiotic factors such as the physical composition of granulometric texture, organic matter and macrophyte banks, to the establishment of bivalves in these floodplain lagoons. We recorded bivalves of Pisidium (native, Diplodon (native, and Corbicula (invasive. The highest values of Diplodon sp. density were observed at São João/C lake, for Pisidium sterkianum (Pilsbry, 1897 at São João/M lake, and to Jatobá/C lagoon with high density of invasive species Corbicula fluminea (Müller, 1774. This study to obtain conduct the first records of freshwater bivalves in floodplains lagoon in the Ilha Grande National Park, and provides contributions to better understanding the ecology of these mollusks. The recording of native species in the region of Upper Paraná River floodplain after a lomg period without new records, demonstrated the importance of protecting the lagoons of the Ilha Grande National Park as they can be a possible refuge to some species of native freshwater bivalves.

  4. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2013-05-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae. Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  5. Antidermatophytic and Toxicological Evaluations of Dichloromethane-Methanol Extract, Fractions and Compounds Isolated from Coula edulis

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    Jean De Dieu Tamokou

    2011-06-01

    Full Text Available Background: Coula edulis Bail (Olacaceae, is an evergreen tree growing to a height of 25-38 m. This study aimed at evaluating the antidermatophytic and toxicological properties of the stem bark of C. edulis extract as well as fractions and compounds isolated from it. Methods: The plant extract was prepared by maceration in CH2Cl2-MeOH (1:1 v/v. The fractionation of this extract was done by silica gel column chromatography. Antidermatophytic activities were assayed using agar dilution method. The acute and sub-acute toxicities of oral administrations of the extract were studied in rodents. Results: The crude extract of C. edulis displayed antidermatophytic activity against the tested microorganisms with highest activity against Microsporum audouinii and Trichophyton mentagrophytes. The fractionation enhanced the antidermatophytic activity in fraction F3 (MIC=0.62-1.25 mg/ml compared to the crude extract (MIC=1.25-5 mg/ml. Further fractionation and purification of the fractions F2 and F3 gave respectively 3-O-β-D-glucopyranoside of sitosterol (MIC=0.20-0.40 mg/ml and a mixture of β-sitosterol, stigmasterol and n-hexadecanoid acid (MIC=0.80 mg/ml. The median lethal doses (LD50 of the crude extract were 16.8 and 19.6 g/kg body weight (BW in male and female mice, respectively. At 200 mg/kg BW, there was a decrease in body weight gain, food and water consumptions. Gross anatomical analysis revealed white vesicles on the liver of the rats treated with the extract at 200 mg/kg BW. This dose also induced significant (P<0.05 changes on hematological and biochemical parameters in rats after 28 days of treatment. Conclusion: These data suggest that the CH2Cl2-MeOH (1:1 v/v extract of C. edulis stem bark possesses antidermatophytic properties. They also show that at high doses (≥ 200 mg/kg BW, the extract has significant hepatotoxic and nephrotoxic activities

  6. Ecofisiología del cultivo de la gulupa (Passiflora edulis Sims)

    OpenAIRE

    Pérez Martínez, Laura Victoria; MELGAREJO, LUZ MARINA; Flórez Gutiérrez, Laura Marcela; Cruz Aguilar, Marisol; Hernández, María Soledad; Hoyos Carvajal, Liliana María; Guerrero, Eugenio; Potosí, Carmen Tulia; Valeryevich Magnitskiy , Stanislav; Velásquez Villamil, Juan David; Nates Parra, María Guiomar; Ospina Torres, Rodolfo; Amaya Márquez, Marisol; Ángel Coca, Catalina; Medina, Julián

    2012-01-01

    Este libro muestra los resultados de la investigación realizada en gulupa (Passiflora edulis Sims), la cual es una de las especies incluidas en la apuesta exportadora de Colombia en la vigencia 2019. En Colombia se cultiva en los departamentos de Risaralda, Quindío, Cundinamarca y Boyacá, entre otros. La demanda por esta fruta se ha incrementado y el sector productivo frutícola colombiano se beneficia con los precios alcanzados en la ventana de exportación cuando no se provee de otras partes ...

  7. Determination of the mineral fraction and rheological properties of microwave modified starch from Canna edulis.

    Science.gov (United States)

    Lares, Mary; Pérez, Elevina

    2006-09-01

    The goal of this study was to evaluate the effect of the physical modification by microwave irradiation on the mineral fraction and rheological properties of starch isolated from Canna edulis rhizomes. Phosphorus, sodium, potassium, magnesium, iron, calcium and zinc were evaluated using atomic absorption spectrophotometry. Rheological properties were determined using both the Brabender amylograph and Brookfield viscosimeter. Except for the calcium concentration, mineral contents decreased significantly (p canna starch may be modified by microwave irradiation in order to change its functional properties. This information should be considered when using microwave irradiation for food processing. Furthermore, the altered functional attributes of canna modified starch could be advantageous in new product development.

  8. cDNA and Gene Structure of MytiLec-1, A Bacteriostatic R-Type Lectin from the Mediterranean Mussel (Mytilus galloprovincialis

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    Imtiaj Hasan

    2016-05-01

    Full Text Available MytiLec is an α-d-galactose-binding lectin with a unique primary structure isolated from the Mediterranean mussel (Mytilus galloprovincialis. The lectin adopts a β-trefoil fold that is also found in the B-sub-unit of ricin and other ricin-type (R-type lectins. We are introducing MytiLec(-1 and its two variants (MytiLec-2 and -3, which both possess an additional pore-forming aerolysin-like domain, as members of a novel multi-genic “mytilectin family” in bivalve mollusks. Based on the full length mRNA sequence (911 bps, it was possible to elucidate the coding sequence of MytiLec-1, which displays an extended open reading frame (ORF at the 5′ end of the sequence, confirmed both at the mRNA and at the genomic DNA sequence level. While this extension could potentially produce a polypeptide significantly longer than previously reported, this has not been confirmed yet at the protein level. MytiLec-1 was revealed to be encoded by a gene consisting of two exons and a single intron. The first exon comprised the 5′UTR and the initial ATG codon and it was possible to detect a putative promoter region immediately ahead of the transcription start site in the MytiLec-1 genomic locus. The remaining part of the MytiLec-1 coding sequence (including the three sub-domains, the 3′UTR and the poly-A signal was included in the second exon. The bacteriostatic activity of MytiLec-1 was determined by the agglutination of both Gram-positive and Gram-negative bacteria, which was reversed by the co-presence of α-galactoside. Altogether, these data support the classification of MytiLec-1 as a member of the novel mytilectin family and suggest that this lectin may play an important role as a pattern recognition receptor in the innate immunity of mussels.

  9. Impacts of Carpobrotus edulis (L. N.E.Br. on the germination, establishment and survival of native plants: a clue for assessing its competitive strength.

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    Ana Novoa

    Full Text Available Does Carpobrotus edulis have an impact on native plants? How do C. edulis' soil residual effects affect the maintenance of native populations? What is the extent of interspecific competition in its invasion process? In order to answer those questions, we established pure and mixed cultures of native species and C. edulis on soil collected from invaded and native areas of Mediterranean coastal dunes in the Iberian Peninsula. We examined the impact of the invader on the germination, growth and survival of seeds and adult plants of two native plant species (Malcolmia littorea (L. R.Br, and Scabiosa atropurpurea L. growing with ramets or seeds of C. edulis. Residual effects of C. edulis on soils affected the germination process and early growth of native plants in different ways, depending on plant species and density. Interspecific competition significantly reduced the germination and early growth of native plants but this result was soil, density, timing and plant species dependent. Also, at any density of adult individuals of C. edulis, established native adult plants were not competitive. Moreover, ramets of C. edulis had a lethal effect on native plants, which died in a short period of time. Even the presence of C. edulis seedlings prevents the recruitment of native species. In conclusion, C. edulis have strong negative impacts on the germination, growth and survival of the native species M. littorea and S. atropurpurea. These impacts were highly depended on the development stages of native and invasive plants. Our findings are crucial for new strategies of biodiversity conservation in coastal habitats.

  10. US Mussel Watch Program: Transuranic element data from Woods Hole Oceanographic Institution 1976-1983. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Palmieri, J.; Livingston, H.; Farrington, J.W.

    1984-05-01

    Bivalves (Mytilus edulis, Mytilus californianus, Crassostrea virginica and Ostrea equestris) were collected once per year during 1976, 1977, and 1978 along the United States coast and analyzed for (239,240)Pu, (241)Am and (137)Cs as part of the U.S. Mussel Watch program. Monthly samples were collected during 1976-1980 from Narragansett Bay, Rhode Island and Bodega Head, California and analyzed for (239,240)Pu, (241)Am, and (137)Cs. There is no evidence in the data for systematic regional or local elevated concentrations of radionuclides as a result of releases from the nuclear fuel cycle. Monthly fluctuations in radionuclide concentrations in the Narragansett Bay mussels appear to be primarily influenced by spawning.

  11. Consumer Preference and Sensory Properties of the Pacific Cupped Oyster (Crassostrea gigas) and the European Flat Oyster (Ostrea edulis)

    NARCIS (Netherlands)

    Houcke, van Jasper; Altintzoglou, Themistoklis; Stieger, Markus; Linssen, Jozef; Luten, Joop

    2016-01-01

    Experts in the oyster supply chain (farmers, retailers, and gourmet chefs) in The Netherlands have suggested that the European flat oyster (Ostrea edulis) has superior sensory qualities compared to the Pacific cupped oyster (Crassostrea gigas). However, scientific evidence is lacking. The aim of

  12. Bonamia exitiosa (Haplosporidia) observed infecting the European flat oyster Ostrea edulis cultured on the Spanish Mediterranean coast

    NARCIS (Netherlands)

    Carrasco, N.; Villalba, A.; Andree, K.; Engelsma, M.Y.; Lacuesta, B.; Ramilo, A.; Gairin, I.; Furones, M.D.

    2012-01-01

    Bonamia exitiosa and Bonamia ostreae are parasites that reproduce within the haemocytes of several oyster species. In Europe, the host species is the flat oyster Ostrea edulis. The parasite B. ostreae has been responsible for mortalities since the late 1970s throughout the European Atlantic coast. B

  13. Seed size variation in the palm Euterpe edulis and the effects of seed predators on germination and seedling survival

    Science.gov (United States)

    Pizo, Marco A.; Von Allmen, Christiane; Morellato, L. Patricia C.

    2006-05-01

    Intraspecific variation in seed size is common in wild plant populations and has important consequences for the reproductive success of individual plants. Multiple, often conflicting evolutionary forces mediated by biotic as well as abiotic agents may maintain such a variation. In this paper we assessed seed size variation in a population of the threatened, commercially important palm Euterpe edulis in southeast Brazil. We investigated (i) how this variation affects the probability of attack by vertebrate and invertebrate post-dispersal seed predators, and (ii) if seed size influences the outcome of seeds damaged by beetles in terms of seed germination and early survival of seedlings. Euterpe edulis seeds varied in diameter from 8.3 to 14.1 mm. Neither insects nor rodents selected the seeds they preyed upon based on seed size. Seed germination and total, shoot and root biomasses of one-year seedlings were significantly and positively affected by seed size. Root biomass and seedling survival were negatively affected by seed damage caused by a scolytid beetle ( Coccotrypes palmarum) whose adults bore into seeds to consume part of the endosperm, but do not oviposit on them. Seed size had a marginally significant effect on seedling survival. Therefore, if any advantage is accrued by E. edulis individuals producing large seeds, this is because of greater seed germination success and seedling vigor. If this is so, even a relatively narrow range of variation in seed size as observed in the E. edulis population studied may translate into differential success of individual plants.

  14. Bamboo thickets alter the demographic structure of Euterpe edulis population: A keystone, threatened palm species of the Atlantic forest

    Science.gov (United States)

    Rother, Débora Cristina; Rodrigues, Ricardo Ribeiro; Pizo, Marco Aurélio

    2016-01-01

    The rapid spread of bamboos can strongly affect forest structure by interfering plant regeneration and reducing local biodiversity. Considering that bamboos exert a negative influence on the plant community, our main goal was to investigate how this influence manifests at the population level. We compared the demographic structure of the threatened palm Euterpe edulis between bamboo and non-bamboo dominated patches within the Atlantic forest. In the study site, the native bamboo Guadua tagoara has created a marked patchiness and heterogeneity in the vegetation. Plots were set up randomly in bamboo and non-bamboo patches and the heights of all E. edulis individuals were measured. Data from canopy openness and litter depth were collected for both patches. Greater number of E. edulis was recorded in bamboo patches. However, frequency distribution of the height classes differed between patches revealing a predominance of seedling and sapling I classes in bamboo patches, in comparison to a more evenly distribution of height classes in non-bamboo patches. The canopy in bamboo patches was more open and the litter depth was thicker. Our analyses evidenced G. tagoara is functioning as a demographic bottleneck of natural population of E. edulis by arresting its later stages of regeneration and in high densities that bamboos may limit recruitment of this palm species.

  15. Consumer Preference and Sensory Properties of the Pacific Cupped Oyster (Crassostrea gigas) and the European Flat Oyster (Ostrea edulis)

    NARCIS (Netherlands)

    Houcke, van Jasper; Altintzoglou, Themistoklis; Stieger, Markus; Linssen, Jozef; Luten, Joop

    2015-01-01

    Experts in the oyster supply chain (farmers, retailers, and gourmet chefs) in The Netherlands have suggested that the European flat oyster (Ostrea edulis) has superior sensory qualities compared to the Pacific cupped oyster (Crassostrea gigas). However, scientific evidence is lacking. The aim of

  16. Partículas flexuosas de aspecto viral aisladas de achira (canna edulis ker.) afectada por clorosis en colombia

    OpenAIRE

    Reichel, Helena

    2010-01-01

    Observaciones al microscopio electrónico de extractos de hojas de achira (Canna edulis) afectada por una clorosis, precedente del departamento del Huila (Colombia) revelaron la presencia de partículas flexuosas de aspecto viral de aproximadamente 600 nm x 10 nm. Este es el primer reporte de partículas flexuosas de aspecto viral infectando a achira en Colombia.

  17. Electron Paramagnetic Resonance Study of Defects in γ-irradiated Marine Mussel (Mytilus galloprovincialis) and Scallop (Pecten jacobaeus) Shells

    Science.gov (United States)

    Köseoğlu, R.; Köksal, F.; Birey, M.

    2004-11-01

    EPR studies have been performed on some gamma-irradiated marine mussels (Mytilus galloprovincialis) and scallops (Pecten jacobaeus) from the families of Mytilidae and Pectinidae, respectively. Before γ-irradiation, the EPR lines of Mytilus galloprovincialis indicated the existence of Mn2+ ions, which were not observed in the powders of scallop shells. γ -irradiation induced defects in powders of Mytilus galloprovincialis shells, were attributed to orthorhombic CO-3 , axial CO3-3 , orthorhombic CO-2 , freely rotating CO-2 , freely rotating SO-2 , axial SO-3 , isotropic PO2-4 and organic free radicals. γ -irradiation induced defects in powders of Pecten jacobaeus shells were attributed to orthorhombic CO-3 , axial CO3-3 , orthorhombic CO-2 , freely rotating CO-2 , freely rotating SO-2 , and axial SO-3 free radicals. The EPR parameters of the free radicals were compared with literature data on similar defects

  18. Composition and antioxidant properties of wild mushrooms Boletus edulis and Xerocomus badius prepared for consumption.

    Science.gov (United States)

    Jaworska, Grażyna; Pogoń, Krystyna; Skrzypczak, Aleksandra; Bernaś, Emilia

    2015-12-01

    Wild edible mushrooms Boletus edulis and Xerocomus badius were prepared for consumption by braising with 10 % canola oil (half of the batch was blanched prior to braising). Fresh X.badius had comparable to B.edulis amounts of proximate components and higher levels of most B-group vitamins and antioxidants. Analyzed mushrooms prepared for consumption fulfilled 7-14 % RDA of vitamin B1 for healthy adults and 15-35, 18-37 and 1 % RDA of B2, B3 and B3 respectively. Prepared for consumption mushrooms were rich in antioxidants containing in 100 g dry weight 164,601 mg total polyphenols, 19-87 mg total flavonoids, 22.1-27.4 mg L-ascorbic acid, 0.531-1.031 mg β-carotene, 0.325-0.456 mg lycopene and 38.64-44.49 mg total tocopherols and presented high antioxidant activity against ABTS (4.9-36.5 mmol TE), against DPPH (7.8-21.3 mmol TE) and in FRAP assay (15.0-28.1 mmol Fe(2+)). Mushrooms prepared for consumption with blanching prior to culinary treatment showed lower antioxidant properties and vitamin content in comparison to mushrooms braised raw.

  19. Total phenolic content, antioxidant and antimicrobial activities of Blepharis edulis extracts

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    Mohaddese Mahboubi

    2013-02-01

    Full Text Available Blepharis edulis is traditionally used as an antiseptic, purgative, aphrodisiac and anti-inflammatory agent. The extractsof plant aerial parts were screened for total phenolic content (TPC gallic acid equivalents (GAE, total flavonoid compound(TFC quercetin equivalents (QE, antioxidant capacity and its antimicrobial activity by micro broth dilution assay. The 50%-inhibition values of BHT and 70% (v/v aqueous ethanol, 70% (v/v aqueous methanol, methanol, and water extracts of B.edulis according to the DPPH method were found to be 19.6, 71.2, 73.7, 81.4, and 218.4 g/ml, respectively. TPC ranged from38.9 to 102.7 mg GAE/g dry extracts. The antimicrobial activity showed that yeast and fungi were sensitive and resistantmicroorganisms to the extracts. The 70%-methanol extract showed more drastic antimicrobial activity than the others. Theantimicrobial activity of ethanolic extract is the same as of the methanolic extract; water extract had the weakest antimicrobialactivity.

  20. Genome-wide identification and characterization of aquaporin gene family in moso bamboo (Phyllostachys edulis).

    Science.gov (United States)

    Sun, Huayu; Li, Lichao; Lou, Yongfeng; Zhao, Hansheng; Gao, Zhimin

    2016-05-01

    Aquaporins (AQPs) are known to play a major role in maintaining water and hydraulic conductivity balance in the plant system. Numerous studies have showed AQPs execute multi-function throughout plant growth and development, including water transport, nitrogen, carbon, and micronutrient acquisition etc. However, little information on AQPs is known in bamboo. In this study, we present the first genome-wide identification and characterization of AQP genes in moso bamboo (Phyllostachys edulis) using bioinformatics. In total, 26 AQP genes were identified by homologous analysis, which were divided into four groups (PIPs, TIPs, NIPs, and SIPs) based on the phylogenetic analysis. All the genes were located on 26 different scaffolds respectively on basis of the gene mapped to bamboo genome. Evolutionary analysis indicated that Ph. edulis was more close to Oryza sativa than Zea mays in the genetic relationship. Besides, qRT-PCR was used to analyze gene expression profiles, which revealed that AQP genes were expressed constitutively in all the detected tissues, and were all responsive to the environmental cues such as drought, water, and NaCl stresses. This data suggested that AQPs may play fundamental roles in maintaining normal growth and development of bamboo, which would contribute to better understanding for the complex regulation mechanism involved in the fast-growing process of bamboo. Furthermore, the result could provide valuable information for further research on bamboo functional genomics.

  1. What science says about khat (Catha edulis Forsk? Overview of chemistry, toxicology and pharmacology

    Directory of Open Access Journals (Sweden)

    Nasir Tajure Wabe

    2012-02-01

    Full Text Available Catha edulis (khat is a plant grown commonly in the horn of Africa. The leaves of khat are chewed by the people for its stimulant action. Khat is an evergreen shrub, which is cultivated as a bush or small tree. The leaves have an aromatic odour. The taste is astringent and slightly sweet. The plant is seedless and hardy, growing in a variety of climates and soils. Khat contains more than 40 alkaloids, glycosides, tannins, amino acids, vitamins and minerals. Many different compounds are found in khat including alkaloids, terpenoids, flavonoids, sterols, glycosides, tannins, amino acids, vitamins and minerals. The phenylalkylamines and the cathedulins are the major alkaloids which are structurally related to amphetamine. The major effects of khat include those on the gastro-intestinal system and on the nervous system. Constipation, urine retention and acute cardiovascular effects may be regarded as autonomic (peripheral nervous system effects; increased alertness, dependence, tolerance and psychiatric symptoms as effects on the central nervous system. The main toxic effects include increased blood pressure, tachycardia, insomnia, anorexia, constipation, general malaise, irritability, migraine and impaired sexual potency in men. The purpose of this review is to summarize the chemistry, pharmacology, toxicology of khat (Catha edulis Forsk. [J Exp Integr Med 2012; 2(1.000: 29-37

  2. Evaluation of gastroprotective activity of Plinia edulis (Vell.) Sobral (Myrtaceae) leaves in rats.

    Science.gov (United States)

    Ishikawa, Tati; Donatini, Raquel dos Santos; Diaz, Ingrit Elida Collantes; Yoshida, Massayoshi; Bacchi, Elfriede Marianne; Kato, Edna Tomiko Myiake

    2008-08-13

    Plinia edulis, an arboreous species popularly known as "cambucá", is native to the Brazilian Atlantic Rain Forest. Despite its traditional uses, no reports are available on the safety of this utilization or on the relationship between the antiulcer activity of its extract and its phytochemical compounds. This paper reports on the investigation of the acute toxicity and gastroprotective effect of the aqueous ethanol extract of leaves of Plinia edulis on HCl/ethanol-induced ulcers. In order to correlate the secondary metabolites and the efficacy of the crude drug in traditional medicine, the extract was submitted to chromatographic fractionation after solvent partition. The extract did not show acute toxicity in mice treated with 5 g/kg p.o., but exhibited significant antiulcer activity in rats at doses of 100, 200, and 400mg/kg p.o., more active than the reference drug lansoprazole.The ethyl acetate fraction yielded beta-amyrin, oleanolic acid, ursolic acid, and maslinic acid, which were identified based on spectrometric analyses. Since antiulcerogenic activity is not restricted to one class of compounds in plants, the triterpenoids isolated in the extract can be associated with the observed effect.

  3. First report of phytochelatins in a mushroom: induction of phytochelatins by metal exposure in Boletus edulis.

    Science.gov (United States)

    Collin-Hansen, Christian; Pedersen, Sindre A; Andersen, Rolf A; Steinnes, Eiliv

    2007-01-01

    Some species of macromycetes (mushrooms) consistently are found to contain high concentrations of toxic metals such as cadmium (Cd) and mercury (Hg), and consumption of wild-growing mushrooms is acknowledged as a significant source for Cd and Hg in humans. Yet little is known about the speciation of Cd and Hg in mushroom tissues. Here we present the first evidence of peptides of the phytochelatin family being responsible for binding a large fraction of Cd in caps of the macromycete Boletus edulis exposed to excess metals. Concentrations of Cd, Zn, Cu and Hg, as well as cytosolic Cd-binding capacity (CCBC), glutathione (GSH) and free proline (Pro) were quantified in fruiting bodies of B. edulis differentially exposed to a wide range of metals. Metal distribution among cytosolic compounds were investigated by size exclusion chromatography (SEC), followed by metal determinations with atomic absorption chromatography (AAS) and HR-ICP-MS. Cd-binding compounds in SEC elutates were investigated further by high performance liquid chromatography-mass spectrometry (HPLC-MS). CCBC was >90 times higher in the exposed group relative to the reference group (Mann-Whitney's P phytochelatins (PCs), a family of cystein-rich oligopeptides, was confirmed in Cd-containing SEC fractions by HPLC-MS. The appearance of more complex PCs was coupled to declining concentrations of GSH. To our knowledge this is the first report demonstrating the presence of PCs in a macromycete.

  4. Pharmacology of Casimiroa edulis; II. Cardiovascular effects in the anesthesized dog.

    Science.gov (United States)

    Vidrio, H; Magos, G A

    1991-06-01

    The cardiovascular effects of an aqueous extract of seeds of Casimiroa edulis were assessed in pentobarbital-anesthetized dogs. The extract produced marked hypotension which lasted more than two hours; it was accompanied by moderate and less persistent bradycardia. The histaminergic nature of these effects was investigated in animals pretreated with the specific antagonists diphenhydramine, cimetidine, or a combination of both agents. These experiments showed that both H1- and H2-receptors were involved in the hypotensive response, while the bradycardia was mediated solely through an H1-mechanism. In open-chest dogs instrumented for recording cardiac output (ascending aortic flow), left ventricular contractility (dp/dt), central venous pressure (superior vena cava), systemic blood pressure, heart rate, total peripheral resistance and stroke volume, the extract decreased blood pressure and peripheral resistance and increased cardiac output and stroke volume, without modifying the other parameters. It was concluded that the cardiovascular pattern of Casimiroa edulis in the dog is that of a peripheral arterial vasodilator and that it increases cardiac output by reducing left ventricular afterload.

  5. Pulsed counter-current ultrasound-assisted extraction and characterization of polysaccharides from Boletus edulis.

    Science.gov (United States)

    You, Qinghong; Yin, Xiulian; Ji, Chaowen

    2014-01-30

    Four methods for extracting polysaccharides from Boletus edulis, namely, hot-water extraction, ultrasonic clearer extraction, static probe ultrasonic extraction, and pulsed counter-current probe ultrasonic extraction (CCPUE), were studied. Results showed that CCPUE has the highest extraction efficiency among the methods studied. Under optimal CCPUE conditions, a B. edulis polysaccharide (BEP) yield of 8.21% was obtained. Three purified fractions, BEP-I, BEP-II, and BEP-III, were obtained through sequential purification by DEAE-52 and Sephadex G-75 chromatography. The average molecular weights of BEP-I, BEP-II, and BEP-III were 10,278, 23,761, and 42,736 Da, respectively. The polysaccharides were mainly composed of xylose, mannose, galactose, and glucose; of these, mannose contents were the highest. The antioxidant activities of the BEPs were further investigated by measurement of their ability to scavenge DPPH and hydroxyl radicals as well as their reducing power. The results indicated that the BEPs have good antioxidant activity.

  6. Analysis of the essential oil of leaves Catha edulis from Yemen

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    M. N. Algabr

    2014-02-01

    Full Text Available Summary.  The essential oil obtained by hydrodistillation from dried aerial parts of Catha edulis  (Celastraceae growing in Yemen and some East Africa countries, was analyzed by gas chromatography-flame ionization detector (GC-FID and gas chromatography coupled with mass spectrometry (GC-MS. The main constituents of the essential oil were carvotanacetone (84.41%, trans pulegol (2.16%, trans para menthan-2-one (1.29%, 2,5-dimethoxy-p-cymene (1.89%. The Other constituents are mainly non oxygenated monoterpenes.Industrial relevance. I've been evaluating extracts Celastraceae plant family, which belongs to the khat plant since antiquity, where it proved that it has many uses in medicine and agriculture is astonishing, and includes stimulant, appetite suppressive, sedative, emetic, purgative, memoryrestorative, male contraceptive, anti-tumour, anti-leukemic,anti-bacterial, insecticidal and insect repellent activities. The study and analysis of the volatile oils of the plant khat real step to find out how to take advantage of these extracts for medical and industrial purposes.Keywords. Celastraceae; Catha edulis; essential oil; carvotanacetone.

  7. Pertumbuhan dan struktur anatomi daun dua varietas ganyong (Canna edulis pada ketersediaan air berbeda

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    OCTAVIANA RAISA DEWI

    2014-05-01

    Full Text Available Dewi OR, Pitoyo A, Anggarwulan E. 2013. Pertumbuhan dan struktur anatomi daun dua varietas ganyong (Canna edulis pada ketersediaan air berbeda. Bioteknologi 11: 5-10. The aim of the research was to study the effect of different water availability on growth and anatomical structure of leaves of two varieties of canna (Canna edulis Kerr., which are verdos varieties (white varieties and morados varieties (red varieties. Information about physiological and anatomical character of canna is important in order to their cropping development. The research done in randomized design with 2 factors and 3 replicates. The first factor was canna’s varieties (white and red. The second factor was water availability in 5 different fields capacities (20%, 40%, 60%, 80% and 100%. The treatments were be done in 8 weeks, with variable measured, the character growth of plant height, fresh weight, dry weight and leaf anatomical structure indexes include stomata, tick of mesophyll and epidermis. The data were analyzed by analysis of varians, followed by DMRT in 5% confident level. The results showed that differences in crop varieties and the availability of water affect the growth and anatomical structure of cannas’ leaves. Optimum growth found in 80% water availability FC both white and red varieties. Fresh weight, dry weight, stomatal index showed a significant difference, while plant height, thick mesophyll and epidermal thickness showed no significant difference. White varieties more resistant to water stress than red varieties.

  8. Canna edulis Ker by-product: chemical composition and characteristics of the dietary fiber.

    Science.gov (United States)

    Juan Zhang; Wang, Zheng-Wu; Shi, Xian-Ming

    2010-08-01

    Canna edulis Ker by-product was recycled and utilized after starch extraction. The chemical composition, physical properties and antioxidant activity of the by-product were investigated. The by-product was mainly composed of dietary fiber (54.84% measured by AOAC method), and the insoluble dietary fiber constituted the major fraction. Then, the chemical composition of dietary fiber was tested using modified AOAC and Englyst methods. The results showed that dietary fiber was comprised of cellulose, hemicelluloses (including xyloglucans, arabinoxylans and glucuronoxylans), pectin and lignin. Moreover, the by-product contained relatively high content of phenolic compounds and exhibited a moderate antioxidant activity. In addition, the by-product showed both high water-holding capacity (12.5 mL/g) and oil-holding capacity (14 mL/g), and its suspension exhibited controllable viscosity. Therefore, the by-product from C. edulis is not only a source of dietary fiber but also a functional ingredient for food industry.

  9. Anodontites trapesialis (LAMARCK, 1819: a bivalve parasite of freshwater fishes / Anodontites trapesialis (LAMARCK, 1819: um bivalve parasito de peixes de água doce

    Directory of Open Access Journals (Sweden)

    Ângela Teresa Silva-Souza

    2008-08-01

    Full Text Available The bivalve mollusk Anodontites trapesialis has been indicated as an alternative source for aquaculture because it is considered a food of good nutritional value with a protein content close to that of fish. Its shells can be utilized as fertilizer and mixed to the food of domestic animals, and the nacre can be used to manufacture buttons and crafts. However, the larvae of A. trapesialis, which are the lasidium type, are obligatory parasites of freshwater fishes, and the introduction of this bivalve in fish farm tanks have caused trouble and losses for producers. Nothing is known, however, about their development in these environments. On the other hand, it should be pointed out that A. trapesialis is on Brazil’s list of species threatened with extinction. This article provides a compilation of information present in the literature, offering a detailed review, with the aim of presenting a general panorama of what is known about Anodontites trapesialis and its larval parasitism of fishes.O molusco bivalve, Anodontites trapesialis, tem sido indicado como fonte alternativa para a aqüicultura, por ser considerado um alimento de bom valor nutricional com um conteúdo protéico próximo ao do pescado. Suas conchas podem ser utilizadas como fertilizantes calcáreos e ser agregadas a alimentos de animais domésticos e o nácar pode ser utilizado para fabricar botões e artesanatos. No entanto, as larvas de A. trapesialis, que são do tipo lasidium, são parasitas obrigatórias de peixes de água doce e a introdução desse bivalve em tanques de piscicultura tem causado transtornos e prejuízos aos produtores. Nada se conhece, porém, sobre o seu desenvolvimento nesses ambientes. Por outro lado, ressalta-se que A. trapesialis consta da lista brasileira de espécies ameaçadas de extinção. No presente artigo são compiladas as informações presentes na literatura, em uma revisão detalhada, com o objetivo de apresentar o panorama geral do

  10. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses.

    Directory of Open Access Journals (Sweden)

    Sikai Wang

    Full Text Available Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI and fatty acid (FA techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25% to particular organic matter (POM in summer, while diatoms contributed the most (12.68 ± 1.17% during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44% and winter (25.51 ± 0.59%, and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems.

  11. Wavelength dispersive X-ray fluorescence analysis using fundamental parameter approach of Catha edulis and other related plant samples

    Energy Technology Data Exchange (ETDEWEB)

    Shaltout, Abdallah A., E-mail: shaltout_a@hotmail.com [Spectroscopy Department, Physics Division, National Research Center, El Behooth Str., 12622 Dokki, Cairo (Egypt); Faculty of science, Taif University, 21974 Taif, P.O. Box 888 (Saudi Arabia); Moharram, Mohammed A. [Spectroscopy Department, Physics Division, National Research Center, El Behooth Str., 12622 Dokki, Cairo (Egypt); Mostafa, Nasser Y. [Faculty of science, Taif University, 21974 Taif, P.O. Box 888 (Saudi Arabia); Chemistry Department, Faculty of Science, Suez Canal University, Ismailia (Egypt)

    2012-01-15

    This work is the first attempt to quantify trace elements in the Catha edulis plant (Khat) with a fundamental parameter approach. C. edulis is a famous drug plant in east Africa and Arabian Peninsula. We have previously confirmed that hydroxyapatite represents one of the main inorganic compounds in the leaves and stalks of C. edulis. Comparable plant leaves from basil, mint and green tea were included in the present investigation as well as trifolium leaves were included as a non-related plant. The elemental analyses of the plants were done by Wavelength Dispersive X-Ray Fluorescence (WDXRF) spectroscopy. Standard-less quantitative WDXRF analysis was carried out based on the fundamental parameter approaches. According to the standard-less analysis algorithms, there is an essential need for an accurate determination of the amount of organic material in the sample. A new approach, based on the differential thermal analysis, was successfully used for the organic material determination. The obtained results based on this approach were in a good agreement with the commonly used methods. Depending on the developed method, quantitative analysis results of eighteen elements including; Al, Br, Ca, Cl, Cu, Fe, K, Na, Ni, Mg, Mn, P, Rb, S, Si, Sr, Ti and Zn were obtained for each plant. The results of the certified reference materials of green tea (NCSZC73014, China National Analysis Center for Iron and Steel, Beijing, China) confirmed the validity of the proposed method. - Highlights: Black-Right-Pointing-Pointer Quantitative analysis of Catha edulis was carried out using standardless WDXRF. Black-Right-Pointing-Pointer Differential thermal analysis was used for determination of the loss of ignition. Black-Right-Pointing-Pointer The existence of hydroxyapatite in Catha edulis plant has been confirmed. Black-Right-Pointing-Pointer The CRM results confirmed the validity of the developed method.

  12. А new Gal/GalNAc-specific lectin from the mussel Mytilus trossulus: Structure, tissue specificity, antimicrobial and antifungal activity.

    Science.gov (United States)

    Chikalovets, Irina V; Kovalchuk, Svetlana N; Litovchenko, Alina P; Molchanova, Valentina I; Pivkin, Mikhail V; Chernikov, Oleg V

    2016-03-01

    In the present study, a new Gal/GalNAc specific lectin from the mussel Mytilus trossulus (designated as MTL) was identified, and its expression levels, both in tissues and toward pathogen stimulation, were then characterized. The MTL primary structure was determined via cDNA sequencing. Deduced sequence of 150 amino acid residues showed 89% similarity to lectins from the mussels Crenomytilus grayanus and Mytilus galloprovincialis that were the first members of a new family of zoolectins. The results indicated that the MTL might be involved in immune response toward pathogen infection, and it might perform different recognition specificity toward bacteria or fungi.

  13. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    DEFF Research Database (Denmark)

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche;

    2012-01-01

    An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social...... and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–environment interactions and policy-related developments and decisions. The Drivers-Pressures-State Change...... to assess DPSIR framework components, are reviewed with a focus on the key environmental issues associated with bivalve farming. Indicator selection criteria are provided to facilitate constraining the number of indicators within the management framework. It is recommended that an ecosystem-based approach...

  14. Anticoagulant activity of marine bivalve Donax incarnates Lin, 1758 Collected from Thazhanguda, Southeast coast of India

    Institute of Scientific and Technical Information of China (English)

    P. Bharathirajan

    2012-01-01

    Objective: Molluscs are highly delicious seafood and they are also very good source for biomedically imported products. Among the molluscs some have pronounced pharmacological activities or other properties which are useful in biomedical area. Methods: In the present study GAGs was isolated from the bivalve such as Donax incarnates. Results: The isolated GAGs were quantified in crude samples and they were estimated as 6.84 gm/kg crude GAGs in Donax incarnates. The bivalve showed the anticoagulant activity of the crude samples 124.53 USP units/mg in Donax incarnates. FTIR analysis reveals the presence of anticoagulant substance signals at different ranges. Conclusions: The determined in this research show that gastropod Donax incarnates tissue is value medicinal due to high quality of anticoagulant compounds.

  15. Contamination of raw bivalve molluscs available in Poland between 2009 and 2013 with marine biotoxins

    Directory of Open Access Journals (Sweden)

    Michalski Mirosław

    2016-12-01

    Full Text Available Introduction: Growing consumption of shellfish is associated with an increased risk of food poisoning. The study was carried out on live bivalve molluscs available on the Polish market between 2009 and 2013. Material and Methods: ELISA was used for the determination of the following marine biotoxins: paralytic shellfish poison (PSP, amnaesic shellfish poison (ASP, and diarrhoeic shellfish poison (DSP. The molluscs, of which seven species were examined, were obtained from wholesale companies and markets. Results: Marine biotoxins were detected below the permitted levels in 67.6% of the samples. The maximum amounts of PSP and ASP biotoxins were found in great scallops (532.6 μg/kg and 1.0 mg/kg respectively and the peak for DSP was in blue mussels (107 μg/kg. Conclusion: The analysis of toxicological status of raw bivalve molluscs available on the market in Poland indicates that they are safe for consumers.

  16. Paleoenvironmental and paleoclimatic significance of freshwater bivalves in the Upper Jurassic Morrison Formation, Western Interior, USA

    Science.gov (United States)

    Good, Steven C.

    2004-05-01

    Freshwater unionid bivalves are spatially and temporally distributed throughout the Morrison depositional basin, and locally dominate the biomass of many aquatic depositional environments. Two bivalve assemblages are identified. Within-channel assemblages are death assemblages that have been transported and may represent mixed assemblages from multiple communities. These assemblages are predominately disarticulated, in current stable orientations, and composed of higher stream velocity ecophenotypes (medium size, lanceolate form, and very thick shells). The floodplain-pond assemblages are disturbed neighborhood assemblages in the mudstones inhabited during life. The bivalves are predominately articulated, variable in size, and composed of low stream velocity ecophenotypes (large maximum sizes, ovate shell shapes, and thinner shells). The glochidial parasitic larval stage of unionid bivalves provides an effective means of dispersing species throughout drainage basins. These larvae attach to fish and are carried through the fluvial drainage where the larvae detach and establish new bivalve communities. Preliminary paleobiogeographic analyses are drawn at the genus level because of the need to reevaluate bivalve species of the Morrison. Unio spp. and Vetulonaia spp. are widespread throughout the Morrison depositional basin, but Hadrodon spp. are restricted to the eastern portion of the Colorado Plateau during Salt Wash Member deposition, suggesting that Salt Wash drainage was isolated from other contemporaneous regions of the basin. Bivalves from five localities in the Morrison Formation were thin-sectioned for growth band analysis. Growth bands of modern unionid bivalves are produced when the valves are forced to close. Closure can produce annual growth bands in response to seasonal variation, such as temperature-induced hibernation, or precipitation-induced aestivation or turbidity. Pseudoannual growth bands form from non-cyclical events such as predation attacks or

  17. Marine Fouling at HMAS STIRLING, Western Australia,

    Science.gov (United States)

    1984-01-01

    sp. Molluscs Anomia trigonopsis Myti.Zus edulis Mytilus edulis %1k Bryozoans Rhamphostomella? sp. Watersipora subovoidea Cryptosula pallasiana Bugula...USA/CAN/NZ ABCA Armies Standardisation Representative (4 copies) Director, Defence Research Centre, Kuala Lumpur, Malaysia Exchange Section, British

  18. [Isolation of enteropathogenic Vibrio in bivalves and mud from the Nicoya Gulf, Costa Rica].

    Science.gov (United States)

    García Cortés, V; Antillón, F

    1990-11-01

    The presence of enteropathogenic Vibrio was evaluated in 36 sediment samples and 41 bivalve samples obtained from 3 collecting sites in the Golfo de Nicoya, Costa Rica. Isolation methods for halophilic and non halophilic Vibrio were used. The biochemical profiles of the strains obtained revealed the presence of the following isolates: 224 Vibrio parahaemolyticus, 3 V. furnissii, 1 V. damsela and 3 V. fluvialis. V. cholerae was not isolated, due principally to the use of TCBS agar.

  19. Bivalves and gastropods from the middle Campanian Anacacho limestone, South Central Texas

    Science.gov (United States)

    Elder, W.P.

    1996-01-01

    The Anacacho Limestone was deposited during the Campanian and represents two depositional intervals, one of early Campanian and one of middle Campanian age. These two intervals correspond to periods of major eustatic sea level rise. This study focuses on the molluscan paleontology of the middle Campanian interval in the eastern part of the Anacacho exposure belt in Medina County, Texas. Molluscan assemblages in this area are indicative of inner to mid-shelf environments. No significant reef components are present. These eastern Anacacho deposits are interpreted to represent more offshore, deeper water environments than those to the southwest, where reef and lagoonal deposits have been reported. Analysis of the macrofossil components from these eastern localities has expanded the number of invertebrate species known from the Anacacho Limestone by nearly three-fold. This increase in diversity, based on a small amount of new work, suggests that many more taxa are yet to be identified, particularly in the western part of the exposure belt in Uvalde and Kinney Counties. This paper documents the bivalve and gastropod fauna, discussing and illustrating 24 bivalve taxa and 11 gastropod species. Two new bivalve species are named, Panopea anacachoensis new species and Spondylus siccus new species, and two potentially new gastropod species are identified but not named herein due to inadequate material. This paper expands the distribution of many eastern Gulf Coast and Atlantic Coast taxa westward into Texas and shows strong ties between the Anacacho fauna and that of the Campanian Tar Heel and Bladen Formations of the Black Creek Group in North Carolina. The taxonomic ties between these two areas probably reflect the thorough documentation of the North Carolina fauna, which is the best documented Campanian bivalve fauna in the Gulf or Atlantic Coast regions.

  20. Evaluation of the antioxidant activity of passion fruit (Passiflora edulis and Passiflora alata) extracts on stimulated neutrophils and myeloperoxidase activity assays.

    Science.gov (United States)

    Zeraik, Maria Luiza; Serteyn, Didier; Deby-Dupont, Ginette; Wauters, Jean-Nöel; Tits, Monique; Yariwake, Janete H; Angenot, Luc; Franck, Thierry

    2011-09-15

    The antioxidant activity of methanol extracts from Passiflora edulis and Passiflora alata pulp, and P. edulis rinds, healthy or infected with the passion fruit woodiness virus (PWV), was investigated using the oxidant activities of the neutrophil and the neutrophil granule enzyme myeloperoxidase (MPO), both playing key roles in inflammation. The reactive oxygen species produced by stimulated neutrophils were evaluated by lucigenin-enhanced chemiluminescence (CL) and the activity of purified MPO was measured by SIEFED (Specific Immunological Extraction Followed by Enzymatic Detection), a technique for studying the direct interaction of a compound with the enzyme. The rind extracts of P. edulis possessed higher and dose-dependent inhibitory effects on CL response and on the peroxidase activity of MPO than total pulp extracts from both passion fruit species. The quantification of isoorientin in the extracts showed a correlation with their antioxidant activity, suggesting the potential of P. edulis rinds as functional food or as a possible source of natural flavonoids.