Cross-kingdom signalling: exploitation of bacterial quorum sensing molecules by the green seaweed Ulva.

Science.gov (United States)

Joint, Ian; Tait, Karen; Wheeler, Glen

2007-07-29

The green seaweed Ulva has been shown to detect signal molecules produced by bacteria. Biofilms that release N-acylhomoserine lactones (AHLs) attract zoospores--the motile reproductive stages of Ulva. The evidence for AHL involvement is based on several independent lines of evidence, including the observation that zoospores are attracted to wild-type bacteria that produce AHLs but are not attracted to mutants that do not produce signal molecules. Synthetic AHL also attracts zoospores and the attraction is lost in the presence of autoinducer inactivation (AiiA) protein. The mechanism of attraction is not chemotactic but involves chemokinesis. When zoospores detect AHLs, the swimming rate is reduced and this results in accumulation of cells at the source of the AHL. It has been demonstrated that the detection of AHLs results in calcium influx into the zoospore. This is the first example of a calcium signalling event in a eukaryote in response to bacterial quorum sensing molecules. The role of AHLs in the ecology of Ulva is discussed. It is probable that AHLs act as cues for the settlement of zoospores, rather than being directly involved as a signalling mechanism.

An evaluation of the toxicity and bioaccumulation of cisplatin in the marine environment using the macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Easton, Cecilia [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Sewell, Graham [School of Health Professions, University of Plymouth, Peninsula Allied Health Centre, Plymouth PL6 8BH (United Kingdom)

2011-12-15

The cytotoxic drug, cisplatin (cis-PtCl{sub 2}(NH{sub 3}){sub 2}), has been added to cultures of the marine macroalga, Ulva lactuca, under various experimental conditions. Both accumulation and internalisation over a 48 h period was greater when cisplatin was added to coastal sea water (salinity = 33) from a distilled water solution than when added to either sea water or estuarine water (salinity = 16.5) from a saline solution. This effect is attributed to the greater abundance of the more reactive monoaqua complex (cis-PtCl(OH{sub 2})(NH{sub 3}){sub 2}{sup +}) in the distilled water solution and kinetic constraints on its conversion back to cis-PtCl{sub 2}(NH{sub 3}){sub 2} in sea water. Despite its mode of action at the cellular level, cisplatin added up to concentrations of 150 nM did not incur a measurable reduction in the efficiency of photochemical energy conversion under any of experimental conditions tested. - Highlights: > This study is the first to examine the biogeochemistry and toxicity of a cytotoxic drug in the marine environment. > Cisplatin is accumulated and internalised by the marine macroalga, Ulva lactuca. > Accumulation is greater when the drug is administered from a distilled water solution than from a saline solution. > Results are consistent with the greater abundance of the more reactive aquated complexes in pure water. > Cisplatin is not phytotoxic to the alga over the concentration range (<150 nM) studied. - The cytotoxic drug, cisplatin, is accumulated and internalised by the marine macroalga, Ulva lactuca, but is not phytotoxic up to concentrations of 150 nM

Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei.

Science.gov (United States)

Elizondo-González, Regina; Quiroz-Guzmán, Eduardo; Escobedo-Fregoso, Cristina; Magallón-Servín, Paola; Peña-Rodríguez, Alberto

2018-01-01

Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1) for wastewater bioremediation, and (2) using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE) resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE). Shrimp under no water exchange (NWE) resulted in significant lower growth and higher feed conversion rate (FCR) compared to the other treatments ( p   0.05). In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL). Shrimp fed the 3 UL diet resulted in a significant ( p  shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

Antimicrobial activity of extracts from macroalgae Ulva lactuca against clinically important Staphylococci is impacted by lunar phase of macroalgae harvest.

Science.gov (United States)

Deveau, A M; Miller-Hope, Z; Lloyd, E; Williams, B S; Bolduc, C; Meader, J M; Weiss, F; Burkholder, K M

2016-05-01

Staphylococcus aureus is a common human bacterial pathogen that causes skin and soft tissue infections. Methicillin-resistant Staph. aureus (MRSA) are increasingly drug-resistant, and thus there is great need for new therapeutics to treat Staph. aureus infections. Attention has focused on potential utility of natural products, such as extracts of marine macroalgae, as a source of novel antimicrobial compounds. The green macroalgae Ulva lactuca produces compounds inhibitory to human pathogens, although the effectiveness of U. lactuca extracts against clinically relevant strains of Staph. aureus is poorly understood. In addition, macroalgae produce secondary metabolites that may be influenced by exogenous factors including lunar phase, but whether lunar phase affects U. lactuca antimicrobial capacity is unknown. We sought to evaluate the antibacterial properties of U. lactuca extracts against medically important Staphylococci, and to determine the effect of lunar phase on antimicrobial activity. We report that U. lactuca methanolic extracts inhibit a range of Staphylococci, and that lunar phase of macrolagae harvest significantly impacts antimicrobial activity, suggesting that antimicrobial properties can be maximized by manipulating time of algal harvest. These findings provide useful parameters for future studies aimed at isolating and characterizing U. lactuca anti-Staphylococcal agents. The growing prevalence of antibiotic-resistant human pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) has intensified efforts towards discovery and development of novel therapeutics. Marine macroalgae like Ulva lactuca are increasingly recognized as potential sources of antimicrobials, but the efficacy of U. lactuca extracts against common, virulent strains of Staph. aureus is poorly understood. We demonstrate that U. lactuca methanolic extracts inhibit a variety of clinically relevant Staphylococcus strains, and that the antimicrobial activity can

Metabolic regulatory oscillations in intertidal green seaweed Ulva lactuca against tidal cycles.

Science.gov (United States)

Gupta, Vishal; Kushwaha, Hemant R

2017-11-27

The survival of wetland plant species largely relies on physiological adaptations essential for submergence and desiccation. Intertidal seaweeds, unlike terrestrial plants, have unique adaptations to submergence and can also sustain desiccation arising from tidal rhythms. This study determined the differential metabolic regulations in the inter-tidal seaweed species Ulva lactuca against the submergence and desiccation. During desiccation, the relative water content of the algal thalli declined with concomitant increase in reactive oxygen species (ROS) and lipid peroxidation. Nevertheless, the trends reversed during recovery on re-submergence and attained homeostasis. Metabolite profiling of U. lactuca revealed desiccation induced balance in energy reserve utilization by adjusting carbohydrate metabolism and switch over to ammonia metabolism. Upon re-submergence, thalli showed an increase in fermentative metabolites, pyruvate-alanine conversion, and the GABA shunt. Prolonged submergence induced substrate level phosphorylation mediated sugar biosynthesis while continuing the alternative carbon flux through fermentative metabolism, an increase in osmoprotectants glycine and betaine, sulfur bearing compounds cysteine and hypotaurine, and phenolic compound coniferaldehyde. The determined metabolic regulations in U. lactuca for submergence tolerance provide insights into potential evolutionarily conserved protective mechanisms across the green lineage and also highlights the possible role of sulfur oxoforms as strong free radical scavengers.

Evaluation of Nutritional Composition of The Dried Seaweed Ulva lactuca from Pameungpeuk Waters, Indonesia.

Science.gov (United States)

Rasyid, Abdullah

2017-07-01

The nutritional composition of the dried seaweed Ulva lactuca from Pameungpeuk waters, including proximate, vitamins, minerals, dietary fibre and heavy metal has been carried out. The objective of this present study is to know the nutritional composition of the dried seaweed U. lactuca for utilisation in human nutrition in the future. Results show that carbohydrate was the major component in the proximate analysis of U. lactuca in the present study. The carbohydrate content was 58.1%. Moisture, ash, protein and fat content were 16.9%, 11.2%, 13.6% and 0.19% respectively, while dietary fibre was 28.4%. The vitamin A content was examined in this study less than 0.5 IU/100 mg while vitamin B1 (thiamine) and vitamin B2 (riboflavin) were 4.87 mg/kg and 0.86 mg/kg respectively. The calcium content was 1828 mg/100 g higher than other minerals. The heavy metal content examined in this study were lower than the limit of the quality criteria applied to edible seaweeds sold in Indonesia. Based on the results of this study show that U. lactuca has potential to be developed as an alternative source of a healthy food for human in the future.

Lead (Pb heavy metal impacts in the green Ulva lactuca (Chlorophyceae marine algae

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B. Saleh

2016-05-01

Full Text Available Toxicity of different lead (Pb (0, 2, 4 and 8 mg/L concentrations in the green Ulva lactuca (Chlorophyta marine algae at physiological level has been investigated 48 h after Pb treatment under laboratory conditions. Thalus algae damages followed Pb treatment as revealed by microscopy test showed that the 4 and 8 mg/L Pb caused morphological changes in cells viability; whereas, no effect observed at the lowest Pb applied concentration (2 mg/L. Data revealed that Pb stress caused reduction in most investigated physiological parameters i.e. Pigments content, osmotic potential and membrane stability index values. This decline in osmotic potential was significantly (p ≤ 0.001 different. Whereas, estimated electric conductivity (EC values increased significantly (p ≤ 0.001 as applied Pb concentration increased. The current study allowed somewhat to highlight and better understanding Pb impacts in U. lactuca algae. Thereby, the studied algae could be used as a useful bioindicator in Pb polluted ecosystems.

Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei

Directory of Open Access Journals (Sweden)

Regina Elizondo-González

2018-03-01

Full Text Available Two experimental feeding trials were conducted during four weeks to evaluate the use of Ulva lactuca in shrimp culture: (1 for wastewater bioremediation, and (2 using different inclusion levels of U. lactuca meal in shrimp feed. In feeding trial 1, shrimp reared under seaweed U. lactuca water exchange in a re-circulation system (SWE resulted in similar growth and feed utilization as shrimp reared with clean water exchange (CWE. Shrimp under no water exchange (NWE resulted in significant lower growth and higher feed conversion rate (FCR compared to the other treatments (p  0.05. In feeding trial 2, U. lactuca biomass produced by wastewater bioremediation in SWE treatment were dried and ground to formulate diets containing 0, 1, 2, and 3% U. lactuca meal (0UL, 1UL, 2UL, and 3UL. Shrimp fed the 3 UL diet resulted in a significant (p < 0.05 improvement of growth and FCR, and enhanced whole shrimp lipid and carotenoid content by 30 and 60%, respectively, compared to control diet. Seaweed U. lactuca is suggested as a desirable species for wastewater bioremediation in integrated aquaculture systems, and its meal as a good feed additive for farmed shrimp.

Marine biomass research in Florida. [Gracilaria tikvahiae, Ulva Lactuca

Energy Technology Data Exchange (ETDEWEB)

Ryther, J.H.

1983-01-01

The red alga Gracilaria tikvahiae may be grown outdoors year-round in central Florida with yields averaging 35.5 g dry weight/sq. m/day, greater than the most productive terrestrial plants. This occurs when the plants are grown in suspended culture, with vigorous aeration and an exchange of 25 or more culture volumes of enriched seawater per day. A culture system was designed in which Gracilaria, stocked at a density of 2 kg wet weight/sq.m, grows to double its biomass in one to two weeks; it is then harvested to its starting density, and anaerobically digested to methane. The biomass is soaked for 6 hours in the digester residue, storing enough nutrients for two week's growth in unenriched seawater. The methane is combusted for energy and the waste gas is fed to the culture to provide mixing of CO/sub 2/ eliminating the need for aeration and seawater exchange. The green alga Ulva lactuca, unlike Gracilaria, uses bicarbonate as a photosynthesis carbon source, and can be grown at high pH, with little or no free CO/sub 2/. It can therefore produce higher yields than Gracilaria in low water exchange conditions. It is also more efficiently converted to methane than is Gracilaria, but cannot tolerate Florida's summer temperatures so cannot be grown year-round. Attempts are being made to locate or produce through selective breeding, a high-temperature tolerant strain of Ulva. 21 references.

Production of acetone, butanol, and ethanol from biomass of the green seaweed Ulva lactuca.

Science.gov (United States)

van der Wal, Hetty; Sperber, Bram L H M; Houweling-Tan, Bwee; Bakker, Robert R C; Brandenburg, Willem; López-Contreras, Ana M

2013-01-01

Green seaweed Ulva lactuca harvested from the North Sea near Zeeland (The Netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. Solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. A hydrolysate was used for the production of acetone, butanol and ethanol (ABE) by Clostridium acetobutylicum and Clostridium beijerinckii. Hydrolysate-based media were fermentable without nutrient supplementation. C. beijerinckii utilized all sugars in the hydrolysate and produced ABE at high yields (0.35 g ABE/g sugar consumed), while C. acetobutylicum produced mostly organic acids (acetic and butyric acids). These results demonstrate the great potential of U. lactuca as feedstock for fermentation. Interestingly, in control cultures of C. beijerinckii on rhamnose and glucose, 1,2 propanediol was the main fermentation product (9.7 g/L). Copyright © 2012 Elsevier Ltd. All rights reserved.

Biorefinery of the green seaweed Ulva lactuca to produce animal feed, chemicals and biofuels.

Science.gov (United States)

Bikker, Paul; van Krimpen, Marinus M; van Wikselaar, Piet; Houweling-Tan, Bwee; Scaccia, Nazareno; van Hal, Jaap W; Huijgen, Wouter J J; Cone, John W; López-Contreras, Ana M

2016-01-01

The growing world population demands an increase in animal protein production. Seaweed may be a valuable source of protein for animal feed. However, a biorefinery approach aimed at cascading valorisation of both protein and non-protein seaweed constituents is required to realise an economically feasible value chain. In this study, such a biorefinery approach is presented for the green seaweed Ulva lactuca containing 225 g protein ( N  × 4.6) kg -1 dry matter (DM). The sugars in the biomass were solubilised by hot water treatment followed by enzymatic hydrolysis and centrifugation resulting in a sugar-rich hydrolysate (38.8 g L -1 sugars) containing glucose, rhamnose and xylose, and a protein-enriched (343 g kg -1 in DM) extracted fraction. This extracted fraction was characterised for use in animal feed, as compared to U. lactuca biomass. Based on the content of essential amino acids and the in vitro N (85 %) and organic matter (90 %) digestibility, the extracted fraction seems a promising protein source in diets for monogastric animals with improved characteristics as compared to the intact U. lactuca . The gas production test indicated a moderate rumen fermentation of U. lactuca and the extracted fraction, about similar to that of alfalfa. Reduction of the high content of minerals and trace elements may be required to allow a high inclusion level of U. lactuca products in animal diets. The hydrolysate was used successfully for the production of acetone, butanol, ethanol and 1,2-propanediol by clostridial fermentation, and the rhamnose fermentation pattern was studied.

Marine Bacteria from Danish Coastal Waters Show Antifouling Activity against the Marine Fouling Bacterium Pseudoalteromonas sp. Strain S91 and Zoospores of the Green Alga Ulva australis Independent of Bacteriocidal Activity▿†

Science.gov (United States)

Bernbom, Nete; Ng, Yoke Yin; Kjelleberg, Staffan; Harder, Tilmann; Gram, Lone

2011-01-01

The aims of this study were to determine if marine bacteria from Danish coastal waters produce antifouling compounds and if antifouling bacteria could be ascribed to specific niches or seasons. We further assess if antibacterial effect is a good proxy for antifouling activity. We isolated 110 bacteria with anti-Vibrio activity from different sample types and locations during a 1-year sampling from Danish coastal waters. The strains were identified as Pseudoalteromonas, Phaeobacter, and Vibrionaceae based on phenotypic tests and partial 16S rRNA gene sequence similarity. The numbers of bioactive bacteria were significantly higher in warmer than in colder months. While some species were isolated at all sampling locations, others were niche specific. We repeatedly isolated Phaeobacter gallaeciensis at surfaces from one site and Pseudoalteromonas tunicata at two others. Twenty-two strains, representing the major taxonomic groups, different seasons, and isolation strategies, were tested for antiadhesive effect against the marine biofilm-forming bacterium Pseudoalteromonas sp. strain S91 and zoospores of the green alga Ulva australis. The antiadhesive effects were assessed by quantifying the number of strain S91 or Ulva spores attaching to a preformed biofilm of each of the 22 strains. The strongest antifouling activity was found in Pseudoalteromonas strains. Biofilms of Pseudoalteromonas piscicida, Pseudoalteromonas tunicata, and Pseudoalteromonas ulvae prevented Pseudoalteromonas S91 from attaching to steel surfaces. P. piscicida killed S91 bacteria in the suspension cultures, whereas P. tunicata and P. ulvae did not; however, they did prevent adhesion by nonbactericidal mechanism(s). Seven Pseudoalteromonas species, including P. piscicida and P. tunicata, reduced the number of settling Ulva zoospores to less than 10% of the number settling on control surfaces. The antifouling alpP gene was detected only in P. tunicata strains (with purple and yellow pigmentation), so

Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: Equilibrium, kinetic and thermodynamic study

International Nuclear Information System (INIS)

Rathinam, Aravindhan; Zou, Linda

2010-01-01

Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of ΔH o and the negative value of ΔG o show that the sorption process is endothermic and spontaneous. The positive value of change in entropy ΔS o shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed.

Bioremediation of reject water from anaerobically digested waste water sludge with macroalgae (Ulva lactuca, Chlorophyta).

Science.gov (United States)

Sode, Sidsel; Bruhn, Annette; Balsby, Thorsten J S; Larsen, Martin Mørk; Gotfredsen, Annemarie; Rasmussen, Michael Bo

2013-10-01

Phosphorus and biologically active nitrogen are valuable nutrient resources. Bioremediation with macroalgae is a potential means for recovering nutrients from waste streams. In this study, reject water from anaerobically digested sewage sludge was successfully tested as nutrient source for cultivation of the green macroalgae Ulva lactuca. Maximal growth rates of 54.57±2.16% FW d(-1) were achieved at reject water concentrations equivalent to 50 μM NH4(+). Based on the results, the growth and nutrient removal was parameterised as function of NH4(+) concentration a tool for optimisation of any similar phycoremediation system. Maximal nutrient removal rates of 22.7 mg N g DW(-1) d(-1) and 2.7 mg P g DW(-1) d(-1) were achieved at reject water concentrations equivalent to 80 and 89 μM NH4(+), respectively. A combined and integrated use of the produced biomass in a biorefinery is thought to improve the feasibility of using Ulva for bioremediation of reject water. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: Equilibrium, kinetic and thermodynamic study

Energy Technology Data Exchange (ETDEWEB)

Rathinam, Aravindhan [Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020 (India); Zou, Linda, E-mail: linda.zou@unisa.edu.au [SA Water Centre for Water Management and Reuse, University of South Australia, Mawson Lakes Campus, Adelaide, SA 5095 (Australia)

2010-12-15

Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of {Delta}H{sup o} and the negative value of {Delta}G{sup o} show that the sorption process is endothermic and spontaneous. The positive value of change in entropy {Delta}S{sup o} shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed.

Biosorption of bovine serum albumin by Ulva lactuca biomass from industrial wastewater: equilibrium, kinetic and thermodynamic study.

Science.gov (United States)

Rathinam, Aravindhan; Zou, Linda

2010-12-15

Batch biosorption experiments have been carried out for the removal of bovine serum albumin (BSA) from simulated industrial wastewater onto Ulva lactuca seaweed. Various vital parameters influencing the biosorption process such as initial concentration of BSA, pH of the solution, adsorbent dosage and temperature have been determined. The biosorption kinetics follows a pseudo-second order kinetic model. Equilibrium isotherm studies demonstrate that the biosorption followed the Freundlich isotherm model, which implies a heterogeneous sorption phenomenon. Various thermodynamic parameters such as changes in enthalpy, free energy and entropy have been calculated. The positive value of ΔH° and the negative value of ΔG° show that the sorption process is endothermic and spontaneous. The positive value of change in entropy ΔS° shows increased randomness at the solid-liquid interface during the biosorption of BSA onto U. lactuca seaweed. Copyright © 2010 Elsevier B.V. All rights reserved.

In vitro exposure of Ulva lactuca Linnaeus (Chlorophyta) to gasoline - Biochemical and morphological alterations.

Science.gov (United States)

Pilatti, Fernanda Kokowicz; Ramlov, Fernanda; Schmidt, Eder Carlos; Kreusch, Marianne; Pereira, Débora Tomazi; Costa, Christopher; de Oliveira, Eva Regina; Bauer, Cláudia M; Rocha, Miguel; Bouzon, Zenilda Laurita; Maraschin, Marcelo

2016-08-01

Refined fuels have considerable share of pollution of marine ecosystems. Gasoline is one of the most consumed fuel worldwide, but its effects on marine benthic primary producers are poorly investigated. In this study, Ulva lactuca was chosen as a biological model due to its cosmopolitan nature and tolerance to high levels and wide range of xenobiotics and our goal was to evaluate the effects of gasoline on ultrastructure and metabolism of that seaweed. The experimental design consisted of in vitro exposure of U. lactuca to four concentrations of gasoline (0.001%, 0.01%, 0.1%, and 1.0%, v/v) over 30 min, 1 h, 12 h, and 24 h, followed by cytochemical, SEM, and biochemical analysis. Increase in the number of cytoplasmic granules, loss of cell turgor, cytoplasmic shrinkage, and alterations in the mucilage were some of the ultrastructural alterations observed in thalli exposed to gasoline. Decrease in carotenoid and polyphenol contents, as well as increase of soluble sugars and starch contents were associated with the time of exposure to the xenobiotic. In combination, the results revealed important morphological and biochemical alterations in the phenotype of U. lactuca upon acute exposure to gasoline. This seaweed contain certain metabolites assigned as candidates to biomarkers of the environmental stress investigated and it is thought to be a promise species for usage in coastal ecosystems perturbation monitoring system. In addition, the findings suggest that U. lactuca is able to metabolize gasoline hydrocarbons and use them as energy source, acting as bioremediator of marine waters contaminated by petroleum derivatives. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dietary Supplementation of Seaweed (Ulva lactuca to alleviate the Impact of Heat Stress in Growing Lambs

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Kkalid A. Abdoun, Aly B. Okab, Ahmed M. El-Waziry, Emad M. Samara and Ahmed A. Al-Haidary

2014-01-01

Full Text Available Several environmental and nutritional management approaches have been used to mitigate heat stress and improve performance of farm animals in semi-arid and arid regions. The present study was designed with the intention to alleviate the negative effects of heat stress and to promote the performance of growing lambs reared under hot environmental conditions. The study was conducted on 18 male Naimey lambs with average body weight of 22.78±0.49 kg, and 4-5 months old. The animals were randomly divided into 3 equal groups (A, B and C, and fed diets containing different concentrations of seaweed (Ulva lactuca for 90 days. Group A served as control and was offered diet containing 0.0% seaweed. Groups B and C served as treated groups and were offered diets containing 3.0 and 5.0% seaweed, respectively. Dietary inclusion of seaweed to the diet of growing lambs exposed to heat stress (max Ta 43.9oC, max RH 81.1%, max THI 84.6 neither influenced (P>0.05 the thermo-physiological parameters (rectal and skin temperatures, nor affected (P>0.05 the performance parameters (feed intake, body weight gain, feed conversion efficiency. Furthermore, dietary seaweed supplementation did not alter (P>0.05 blood constituents or blood antioxidant capacity. However, dietary seaweed supplementation significantly (P<0.05 reduced respiratory rate, and increased serum potassium concentration. Based on the data of the present study, seaweed (Ulva lactuca supplementation to the diets of growing lambs reared under heat stress conditions did not show any indication of promoting their production performance or heat tolerance.

Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Masakorala, Kanaji [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: aturner@plymouth.ac.uk; Brown, Murray T. [School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2008-12-15

Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga.

Influence of synthetic surfactants on the uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca

International Nuclear Information System (INIS)

Masakorala, Kanaji; Turner, Andrew; Brown, Murray T.

2008-01-01

Uptake of Pd, Cd and Pb by the marine macroalga, Ulva lactuca, has been studied in the presence of an anionic (sodium dodecyl sulphate, SDS), cationic (hexadecyltrimethylammonium bromide; HDTMA) and non-ionic (Triton X-100; TX) surfactant. Compared with the surfactant-free system, metal sorption was reduced in the presence of SDS or TX. Neither surfactant, however, had any measurable impact on cell membrane permeability, determined by leakage of dissolved free amino acids (DFAA), or on metal internalisation. We attribute these observations to the stabilisation of aqueous Cd and Pb by SDS and the shielding of otherwise amenable sorption sites by TX. Presence of HDTMA resulted in a reduction in the extent of both sorption and internalisation of all metals and a significant increase in the leakage of DFAA. Thus, by enhancing membrane permeability, HDTMA exerts the greatest influence on metal behaviour in the presence of U. lactuca. - Synthetic surfactants exert a significant impact on the uptake and internalisation of metals by a marine macroalga

Effect of dietary seaweed (Ulva lactuca) supplementation on growth performance of sheep and on in vitro gas production kinetics

OpenAIRE

EL-WAZIRY, Ahmed; AL-HAIDARY, Ahmed; OKAB, Aly; SAMARA, Emad; ABDOUN, Khalid

2015-01-01

This study was carried out to determine the effect of dietary seaweed (Ulva lactuca) supplementation on growth performance of sheep, in vitro gas production, estimated energy, and microbial protein synthesis. A total of 18 Naimey male sheep with average live weight of 22.78 ± 0.24 kg were randomly allocated to 3 groups. Sheep in group 1 were fed a diet containing commercial feed without seaweed as a control diet, sheep in group 2 were fed the control diet with 3% seaweed, and sheep in group 3...

Detection of Genetic Variations in Marine Algae Ulva lactuca (Chlorophyta Induced by Heavy Metal Pollutants

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Basel Saleh

2015-09-01

Full Text Available Ulva lactuca (Chlorophyta green macroalgae has been successfully used as bioindicator for heavy metals pollution in ecosystems. Random amplified microsatellite polymorphism (RAMP marker was employed to investigate genetic DNA pattern variability in green U. lactuca 5 days after exposure to Cu, Pb, Cd and Zn heavy metals stress. Genomic template stability (GTS% value was employed as a qualitative DNA changes measurement based on RAMP technique. In this respect, estimated GTS% value was recorded to be 65.215, 64.630, 59.835 and 59.250% for Pb, Cu, Cd and Zn treatment, respectively. Moreover, genetic similarity (GS induced by the above heavy metals was also evaluated to measure genetic distance between algae treated plants and their respective control. In this respect, estimated GS values generated by RAMP marker ranged between 0.576 (between control and Zn treatment - 0.969 (for both case; between Pb and Cu and between Cd and Zn treatment with an average of 0.842. Based upon data presented herein based on variant bands number (VB, GTS% and GS values; the present study could be suggested that Pb and Cu followed similar tendency at genomic DNA changes. Similar finding was also observed with Cd and Zn ions. Thereby, RAMP marker successfully highlighted DNA change patterns induced by heavy metals stress.

Effects of different drying conditions on the rehydration ratio and water holding capacity properties in three different species of algae Ulva lactuca, Codium vermilara and Codium tomentosum

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Paulo Marques Nunes

2014-06-01

In this work, it was concluded that higher drying temperature conditions originate lower rehydration ratio and consequent lower water holding capacity possibly due to a higher physical damage in the algae tissues. It was also observed that both Codium species have higher values for these two parameters than Ulva lactuca, under the same rehydration conditions.

Nutrient uptake efficiency of Gracilaria chilensis and Ulva lactuca in an IMTA system with the red abalone Haliotis rufescens

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Juan Macchiavello

2014-07-01

Full Text Available The current study examined the nutrient uptake efficiency of Ulva lactuca and Gracilaria chilensis cultivated in tanks associated with the wastewater of a land-based abalone culture. The experiments evaluated different seaweed stocking densities (1200, 1900, 2600, and 3200 g m-2 and water exchange rates (60, 80, 125, and 250 L h-1. The results show that both U. lactuca and G. chilensis were efficient in capturing and removing all of the inorganic nutrients originating from the abalone cultivation for all of the tested conditions. Furthermore, an annual experiment was performed with U. lactuca, cultivated at a stocking density of 1900 g m-2 and at a water exchanged rate of 125 L h-1, in order to evaluate seasonal changes in the nutrient uptake efficiency, productivity, and growth rate associated with the wastewater of a land-based abalone culture. The results confirmed high uptake efficiency during the entire year, equivalent to a 100% removal of the NH4, NO3, and PO4 produced by the land-based abalone culture. The growth rate and productivity of U. lactuca presented a marked seasonality, increasing from fall until summer and varying from 0.5 ± 0.2% to 2.6 ± 0.2% d-1 and 10 ± 6.1% to 73.6 ± 8.4% g m-2 d-1 for sustainable growth rate and productivity, respectively. We conclude that there is sufficient evidence that demonstrates the high possibility of changing the traditional monoculture system of abalone in Chile, to a sustainable integrated multi-trophic aquaculture system, generating positive environmental externalities, including the use of U. lactuca as a biofiltration unit.

Chemical and biological evaluation of the nutritive value of Algerian green seaweed Ulva lactuca using in vitro gas production technique fior ruminant animals

OpenAIRE

Zitouni, Hind; Arhab, Rabah; Boudry, Christelle; Bousseboua, Hacène; Beckers, Yves

2014-01-01

This study aimed to determine the nutritive value of seaweed Ulva lactuca collected from the Algerian coast by estimation of its chemical composition and fermentation characteristics, comparatively to vetch-oat hay (control), using in vitro gas production technique. Seaweed and control were incubated with rumen liquor taken from fistulated and non lactating cows. Gas production was recorded at: 2, 4, 6, 8, 12, 24, 48 and 72h. The in vitro rumen fermentation parameters were measured after 24h ...

Influence of seaweed liquid fertilizer of ulva lactuca on the seed germination, growth, productivity of Abelmoschus esculentus (L.

Directory of Open Access Journals (Sweden)

Kaisarla Divya

2015-12-01

Full Text Available The present investigation is an attempt to study the influence of seaweed liquid fertiliger (SLF extracted from the marine green algae ulva lactuca on the growth parameters of Abelmoschus esculentus (l medikus. The seeds were soaked in different concentrations of SLF viz., 2.5%, 5%, 10%, 20% and control for 6h. The foliar spry was applied twice at four concentrations of seaweed extract. The maximum growth was recorded at 5% concentration viz., seed germination, shoot length, root length, no. of flowers, no. of fruits, fresh weight and dry weight when compare to control and remaining concentrations of seaweed extract. The seaweed extract are found effective in increasing the growth parameters.

An evaluation of the toxicity and bioaccumulation of thallium in the coastal marine environment using the macroalga, Ulva lactuca.

Science.gov (United States)

Turner, Andrew; Furniss, Oliver

2012-12-01

Thallium(I) has been added to cultures of the marine macroalga, Ulva lactuca, for a period of 48 h and the accumulation of the metal and its effects on the photochemical efficiency of photosystem II (PS II) measured. Thallium elicited a measurable toxic response above concentrations of 10 μg L⁻¹ in both coastal seawater (salinity 33) and estuarine water (salinity 20). The accumulation of Tl was defined by a linear relationship with aqueous Tl and accumulation factors of about 900 mL g⁻¹ in both media. Thallium accumulated by U. lactuca that was resistant to an EDTA extraction and, by operational definition, internalised, exceeded 90% in both cases. Accumulation and toxicity of Tl in the presence of a ∼10⁵-fold excess of its biogeochemical analogue, potassium, suggests that Tl has a high intrinsic phytotoxicity and that its mode of action involves permeation of the cell membrane as Tl⁺ through NaCl-KCl co-transporter sites rather than (or in addition to) transport through K⁺ ion channels. Copyright © 2012 Elsevier Ltd. All rights reserved.

Solar ultraviolet radiation affects the activity of ribulose-1, 5-bisphosphate carboxylase-oxygenase and the composition of photosynthetic and xanthophyll cycle pigments in the intertidal green alga Ulva lactuca L.

NARCIS (Netherlands)

Bischof, K; Krabs, G; Wiencke, C; Hanelt, D

The effect of solar UV radiation on the physiology of the intertidal green macroalga Ulva lactuca L. was investigated. A natural Ulm community at the shore of Helgoland was covered with screening foils, excluding UV-B or UV-B + UV-A from the solar spectrum. In the sampled material, changes in the

Chemical compositions of the marine algae Gracilaria salicornia (Rhodophyta) and Ulva lactuca (Chlorophyta) as a potential food source.

Science.gov (United States)

Tabarsa, Mehdi; Rezaei, Masoud; Ramezanpour, Zohreh; Waaland, Joseph Robert

2012-09-01

The nutritional compositions of two edible red (Gracilaria salicornia) and green (Ulva lactuca) seaweeds were determined to evaluate their possible uses as potential food ingredients. In general, these species contained limited amounts of lipids ranging between 0.99 and 2.00 g 100 g(-1) dry weight) and considerably high amount of minerals, especially in G. salicornia (38.91 g 100 g(-1) d.w.). The crude protein values varied between 9.58 and 10.69 g 100 g(-1) d.w. Amounts for total amino acids were 889.78 ± 22.64 mg g(-1) protein d.w. in G. salicornia and 543.3 ± 15.14 mg g(-1) protein d.w. in U. lactuca. The most abundant fatty acids were C12:0, C16:0, C20:4 ω6 and C22:5 ω3, in addition to C18:1 in G. salicornia. Both seaweed species were balanced sources of ω3 and ω6 fatty acids with a ratio of ω6/ω3 that varied between 1.2 and 1.17. Between the seaweeds investigated, high levels of K (2414.02-11 380.06 mg 100 g(-1) d.w.) were observed and the amounts of Ca, Na and Fe were higher than those reported for land plants. Thus, G. salicornia and U. lactuca may be utilised as value-added products for human nutrition purposes. Copyright © 2012 Society of Chemical Industry.

Structure and cytotoxic activity of ulvan extracted from green seaweed Ulva lactuca.

Science.gov (United States)

Thanh, Thi Thu Thuy; Quach, Thi Minh Thu; Nguyen, Thi Nu; Vu Luong, Dang; Bui, Minh Ly; Tran, Thi Thanh Van

2016-12-01

The structure of an ulvan obtained by water extraction from green seaweed Ulva lactuca was elucidated by using IR, NMR, SEC-MALL and ESIMS methods. The ulvan was also evaluated for its cytotoxic effects on three human cancer cell lines. The results showed that the ulvan was composed of rhamnose, galactose, xylose, manose, glucose (with a mole ratio of Rha: Gal: Xyl: Man: Glu equal to 1: 0.03: 0.07: 0.01: 0.06), uronic acid (21.5%) and sulfate content (18.9%) with a molecular weight of 347000. This ulvan mainly consists of disaccharide [→4)-β-d-GlcA-(1→4)-α-l-Rha3S-(1→] and other minor disaccharide β-GlcA-(1→2)-α-Xyl and β-GlcA-(→2)-α-Rha. The ulvan showed a significant cytotoxic activity against hepatocellular carcinoma (IC 50 29.67±2.87μg/ml), human breast cancer (IC 50 25.09±1.36μg/ml), and cervical cancer (IC 50 36.33±3.84μg/ml). Copyright © 2016 Elsevier B.V. All rights reserved.

Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta: comparison with Ulva mutabilis and potential for laboratory culture

Directory of Open Access Journals (Sweden)

Eleanor Fay Vesty

2015-01-01

Full Text Available Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development and evolution. They are untapped resources for food, fuel and high-value compounds, but can also form nuisance blooms. To fully analyse green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal-bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. Ulva linza can be reliably induced to sporulate (form gametes and zoospores in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors. The germ cells work as an ideal feed stock for standardized algae cultures.The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal-microbial interactions.

Biorefinery of the macroalgae Ulva lactuca: extraction of proteins and carbohydrates by mild disintegration.

Science.gov (United States)

Postma, P R; Cerezo-Chinarro, O; Akkerman, R J; Olivieri, G; Wijffels, R H; Brandenburg, W A; Eppink, M H M

2018-01-01

The effect of osmotic shock, enzymatic incubation, pulsed electric field, and high shear homogenization on the release of water-soluble proteins and carbohydrates from the green alga Ulva lactuca was investigated in this screening study. For osmotic shock, both temperature and incubation time had a significant influence on the release with an optimum at 30 °C for 24 h of incubation. For enzymatic incubation, pectinase demonstrated being the most promising enzyme for both protein and carbohydrate release. Pulsed electric field treatment was most optimal at an electric field strength of 7.5 kV cm -1 with 0.05 ms pulses and a specific energy input relative to the released protein as low as 6.6 kWh kg prot -1 . Regarding literature, this study reported the highest protein (~ 39%) and carbohydrate (~ 51%) yields of the four technologies using high shear homogenization. Additionally, an energy reduction up to 86% was achieved by applying a novel two-phase (macrostructure size reduction and cell disintegration) technique.

[Seasonal variations of metal contents (Cd, Cu, Fe, Mn and Zn) in seaweed Ulva lactuca from the coast of El Jadida city (Morocco)].

Science.gov (United States)

Kaimoussi, Aziz; Mouzdahir, Abdelkrim; Saih, Abdelkbir

2004-04-01

The quality of El Jadida Atlantic coastal water was monitored from April 1998 to March 1999 by measuring hydrological parameters (dissolved oxygen, suspended particulate matter, phosphates and nitrites) and using the seaweed Ulva lactuca as a quantitative bio-indicator of cadmium, copper, iron, manganese and zinc contamination. Metal content in seaweeds, collected every month from four stations characterized by the discharge of urban and industrial waste water, showed significant variations depending on the station and sampling period. However, the seaweed of El Jadida exhibited generally lower contents compared to those of similar species from other geographical areas.

A macroalgae-based biotechnology for water remediation: Simultaneous removal of Cd, Pb and Hg by living Ulva lactuca.

Science.gov (United States)

Henriques, Bruno; Rocha, Luciana S; Lopes, Cláudia B; Figueira, Paula; Duarte, A C; Vale, Carlos; Pardal, M A; Pereira, E

2017-04-15

Metal uptake from contaminated waters by living Ulva lactuca was studied during 6 days, under different relevant contamination scenarios. In mono-metallic solutions, with concentrations ranging from 10 to 100 μg L -1 for Hg, 10-200 μg L -1 for Cd, and 50-1000 μg L -1 for Pb, macroalgae (500 mg L -1 , d.w.) were able to remove, in most cases 93-99% of metal, allowing to achieve water quality criteria regarding both surface and drinking waters. In multi-metallic solutions, comprising simultaneously the three metals, living macroalgae still performed well, with Hg removal (c.a. 99%) not being significantly affected by the presence of Cd and Pb, even when those metals were in higher concentrations. Removal efficiencies for Cd and Pb varied between 57 and 96%, and 34-97%, respectively, revealing an affinity of U. lactuca toward metals: Hg > Cd > Pb. Chemical quantification in macroalgae, after bioaccumulation assays demonstrated that all Cd and Hg removed from solution was really bound in macroalgae biomass, while only half of Pb showed to be sorbed on the biomass. Overall, U. lactuca accumulated up to 209 μg g -1 of Hg, up to 347 μg g -1 of Cd and up to 1641 μg g -1 of Pb, which correspond to bioconcentration factors ranging from 500 to 2200, in a dose-dependent accumulation. Pseudo-first order, pseudo-second order and Elovich models showed a good performance in describing the kinetics of bioaccumulation, in the whole period of time. In the range of experimental conditions used, no mortality was observed and U. lactuca relative growth rate was not significantly affected by the presence of metals. Results represent an important contribution for developing a macroalgae-based biotechnology, applied for contaminated saline water remediation, more "green" and cost-effective than conventional treatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Differential growth response of Ulva lactuca to ammonium and nitrate assimilation

DEFF Research Database (Denmark)

Ale, Marcel Tutor; Mikkelsen, Jørn Dalgaard; Meyer, Anne S

2011-01-01

and fluctuating levels of nitrogen sources. Our understanding of the influences of this varying condition on the uptake and growth responses of U. lactuca is limited. In this present work, we examined the growth response of U. lactuca exposed to different sources of nitrogen (NH4+; NO3−; and the combination NH4NO...... as the nitrogen source. The NH4Cl and NaNO3 rich media (50 μM of N) accelerated U. lactuca growth to a maximum specific growth rate of 16.4 ± 0.18% day−1 and 9.4 ± 0.72% day−1, respectively. The highest biomass production rate obtained was 22.5 ± 0.24 mg DW m−2·day−1. The presence of ammonium apparently...... discriminated the nitrate uptake by U. lactuca when exposed to NH4NO3. Apart from showing the significant differential growth response of U. lactuca to different nitrogen sources, the work exhibits the applicability of a photo-scanning approach for acquiring precise quantitative growth data for U. lactuca...

Ulva blooms in the southwestern Gulf of California: Reproduction and biomass

Science.gov (United States)

Chávez-Sánchez, Tonatiuh; Piñón-Gimate, Alejandra; Serviere-Zaragoza, Elisa; López-Bautista, Juan Manuel; Casas-Valdez, Margarita

2018-01-01

Ulvacean blooms are generally characterized by one or more Ulva species, some of which are common to blooms across a broad geographic range. In tropical environments the identified stimuli that induce reproductive development of Ulva are restricted to temperature, salinity, dehydration and fragmentation. Culture studies have been prolific in describing the reproduction of Ulva species, but its reproductive changes in natural environment have not been described yet. Hence, seasonal changes were described in reproductive stages and their relationship with biomass and environmental factors of Ulva species at four macroalgal blooms in a subtropical bay. Eight Ulva species were found: U. acanthophora, U. clathrata, U. flexuosa, U. intestinalis, U. lactuca, U. lobata, U. nematoidea and U. rigida. Reproductive stage and biomass varied according to site and season. Five species showed four reproductive stages (vegetative, thallus with fully differentiated zooids in formation and empty cells after zooids release); for the remaining species only vegetative thalli were found. Ulva rigida showed the highest biomass values, followed by U. acanthophora, following a seasonal pattern.

Enzymatic regulation of photosynthetic and light-independent carbon fixation in Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta and Iridaea cordata (Rhodophyta Regulación enzimática de la fotosíntesis y la fijación de carbono en obscuridad por Laminaria setchellii (Phaeophyta, Ulva lactuca (Chlorophyta e Iridaea cordata (Rhodophyta

Directory of Open Access Journals (Sweden)

ALEJANDRO CABELLO-PASINI

2001-06-01

Full Text Available Carbon is acquired through photosynthetic and non-photosynthetic processes in marine algae. However, little is known about the biochemical regulation of these metabolic pathways along the thallus of seaweeds. Consequently, the objective of this study was to assess the distribution of in vivo carboxylation pathways and to relate them to the in vitro activity of ribulose 1,5-bisphosphate carboxylase/oxygenase (RUBISCO, phosphoenolpyruvate carboxykinase (PEPCK, and phosphoenolpyruvate carboxylase (PEPC in the Phaeophyte Laminaria setchellii, the Chlorophyte Ulva lactuca, and the Rhodophyte Iridaea cordata. Chlorophyll-a levels did not vary in U. lactuca and I. cordata. However, pigment levels were significantly lower in the meristematic region of L. setchellii probably as a result of a lack of differentiation of the chloroplasts in this region. Similarly, net photosynthesis did not vary in the thallus of U. lactuca and I. cordata, while it increased from the stipe and meristem towards the lamina of L. setchellii. In contrast to photosynthesis, light-independent carbon fixation rates were significantly greater in the meristematic region of L. setchellii suggesting a compensating mechanism for carbon incorporation in photosynthetically limited tissue. The activity of RUBISCO and PEPCK followed a pattern similar to that of in vivo carboxylation processes indicating that in vivo carbon assimilation is regulated by the activity of the carboxylating enzymes throughout the thallus of L. setchelliiLa incorporación de carbono en algas marinas se lleva a cabo mediante procesos fotosintéticos y no-fotosintéticos. Sin embargo, poco se sabe sobre la regulación bioquímica de estas rutas metabólicas en el tejido de algas marinas. En consecuencia, el objetivo de este estudio fue el de evaluar la distribución de la carboxilación in vivo y relacionarlas a la actividad in vitro de ribulosa 1,5-bisfosfato carboxilasa/oxigenasa (RUBISCO, fosfoenolpiruvato

Regulation of gametogenesis and zoosporogenesis in Ulva linza (Chlorophyta): comparison with Ulva mutabilis and potential for laboratory culture

Science.gov (United States)

Vesty, Eleanor F.; Kessler, Ralf W.; Wichard, Thomas; Coates, Juliet C.

2015-01-01

Green Ulvophyte macroalgae represent attractive model systems for understanding growth, development, and evolution. They are untapped resources for food, fuel, and high-value compounds, but can also form nuisance blooms. To fully analyze green seaweed morphogenesis, controlled laboratory-based culture of these organisms is required. To date, only a single Ulvophyte species, Ulva mutabilis Føyn, has been manipulated to complete its whole life cycle in laboratory culture and to grow continuously under axenic conditions. Such cultures are essential to address multiple key questions in Ulva development and in algal–bacterial interactions. Here we show that another Ulva species, U. linza, with a broad geographical distribution, has the potential to be grown in axenic culture similarly to U. mutabilis. U. linza can be reliably induced to sporulate (form gametes and zoospores) in the laboratory, by cutting the relevant thallus tissue into small pieces and removing extracellular inhibitors (sporulation and swarming inhibitors). The germ cells work as an ideal feed stock for standardized algae cultures. The requirement of U. linza for bacterial signals to induce its normal morphology (particularly of the rhizoids) appears to have a species-specific component. The axenic cultures of these two species pave the way for future comparative studies of algal–microbial interactions. PMID:25674100

Removal of basic dye methylene blue by using bioabsorbents Ulva ...

African Journals Online (AJOL)

In the present study, the removal of textile dye methylene blue was studied by adsorption technique using adsorbents such as, alumina, Ulva lactuca and Sargassum (Maine algae). The batch technique was adopted under the optimize condition of amount of adsorbent, stay time, concentration, temperature and pH. By using ...

Seasonal changes in nutrient limitation and nitrate sources in the green macroalga Ulva lactuca at sites with and without green tides in a northeastern Pacific embayment.

Science.gov (United States)

Van Alstyne, Kathryn L

2016-02-15

In Penn Cove, ulvoid green algal mats occur annually. To examine seasonal variation in their causes, nitrogen and carbon were measured in Ulva lactuca in May, July, and September and stable nitrogen and oxygen isotope ratios were quantified in U. lactuca, Penn Cove seawater, upwelled water from Saratoga Passage, water near the Skagit River outflow, and effluents from wastewater treatment facilities. Ulvoid growth was nitrogen limited and the sources of nitrogen used by the algae changed during the growing season. Algal nitrogen concentrations were 0.85-4.55% and were highest in September and at sites where algae were abundant. Upwelled waters were the primary nitrogen source for the algae, but anthropogenic sources also contributed to algal growth towards the end of the growing season. This study suggests that small nitrogen inputs can result in crossing a "tipping point", causing the release of nutrient limitation and localized increases in algal growth. Copyright © 2015 Elsevier Ltd. All rights reserved.

A link between lead and cadmium kinetic speciation in seawater and accumulation by the green alga Ulva lactuca

International Nuclear Information System (INIS)

Muse, J.O.; Carducci, C.N.; Stripeikis, J.D.; Tudino, M.B.; Fernandez, F.M.

2006-01-01

In this work, studies on the bioaccumulation of Cd and Pb by Ulva lactuca at different sites of Gulf San Jorge (Patagonia, Argentina) are presented. Higher values of bioaccumulated Cd were found in Punta Maqueda - a site believed to serve as a control - in comparison to those in Punta Borja, a place highly exposed to urban and industrial activities. Consequently; the labile fractions of Cd and Pb in seawater were determined with a flow injection-preconcentration manifold interfaced to a graphite furnace-atomic absorption spectrometer (FI-GFAAS). The results obtained by kinetic speciation showed that the variable that correctly explains heavy metals accumulation in the alga, is the labile metal fraction in seawater. We propose to use an enhancement ratio - on the basis of the kinetically labile metal fraction - for calculation of the metal accumulated by the alga relative to its environment. - Metal kinetic speciation can overcome CF limitations for the evaluation of marine pollution

Methanosarcina Play an Important Role in Anaerobic Co-Digestion of the Seaweed Ulva lactuca: Taxonomy and Predicted Metabolism of Functional Microbial Communities.

Directory of Open Access Journals (Sweden)

Jamie A FitzGerald

Full Text Available Macro-algae represent an ideal resource of third generation biofuels, but their use necessitates a refinement of commonly used anaerobic digestion processes. In a previous study, contrasting mixes of dairy slurry and the macro-alga Ulva lactuca were anaerobically digested in mesophilic continuously stirred tank reactors for 40 weeks. Higher proportions of U. lactuca in the feedstock led to inhibited digestion and rapid accumulation of volatile fatty acids, requiring a reduced organic loading rate. In this study, 16S pyrosequencing was employed to characterise the microbial communities of both the weakest (R1 and strongest (R6 performing reactors from the previous work as they developed over a 39 and 27-week period respectively. Comparing the reactor communities revealed clear differences in taxonomy, predicted metabolic orientation and mechanisms of inhibition, while constrained canonical analysis (CCA showed ammonia and biogas yield to be the strongest factors differentiating the two reactor communities. Significant biomarker taxa and predicted metabolic activities were identified for viable and failing anaerobic digestion of U. lactuca. Acetoclastic methanogens were inhibited early in R1 operation, followed by a gradual decline of hydrogenotrophic methanogens. Near-total loss of methanogens led to an accumulation of acetic acid that reduced performance of R1, while a slow decline in biogas yield in R6 could be attributed to inhibition of acetogenic rather than methanogenic activity. The improved performance of R6 is likely to have been as a result of the large Methanosarcina population, which enabled rapid removal of acetic acid, providing favourable conditions for substrate degradation.

Methanosarcina Play an Important Role in Anaerobic Co-Digestion of the Seaweed Ulva lactuca: Taxonomy and Predicted Metabolism of Functional Microbial Communities.

Science.gov (United States)

FitzGerald, Jamie A; Allen, Eoin; Wall, David M; Jackson, Stephen A; Murphy, Jerry D; Dobson, Alan D W

2015-01-01

Macro-algae represent an ideal resource of third generation biofuels, but their use necessitates a refinement of commonly used anaerobic digestion processes. In a previous study, contrasting mixes of dairy slurry and the macro-alga Ulva lactuca were anaerobically digested in mesophilic continuously stirred tank reactors for 40 weeks. Higher proportions of U. lactuca in the feedstock led to inhibited digestion and rapid accumulation of volatile fatty acids, requiring a reduced organic loading rate. In this study, 16S pyrosequencing was employed to characterise the microbial communities of both the weakest (R1) and strongest (R6) performing reactors from the previous work as they developed over a 39 and 27-week period respectively. Comparing the reactor communities revealed clear differences in taxonomy, predicted metabolic orientation and mechanisms of inhibition, while constrained canonical analysis (CCA) showed ammonia and biogas yield to be the strongest factors differentiating the two reactor communities. Significant biomarker taxa and predicted metabolic activities were identified for viable and failing anaerobic digestion of U. lactuca. Acetoclastic methanogens were inhibited early in R1 operation, followed by a gradual decline of hydrogenotrophic methanogens. Near-total loss of methanogens led to an accumulation of acetic acid that reduced performance of R1, while a slow decline in biogas yield in R6 could be attributed to inhibition of acetogenic rather than methanogenic activity. The improved performance of R6 is likely to have been as a result of the large Methanosarcina population, which enabled rapid removal of acetic acid, providing favourable conditions for substrate degradation.

Water-stable diblock polystyrene-block-poly(2-vinyl pyridine) and diblock polystyrene-block-poly(methyl methacrylate) cylindrical patterned surfaces inhibit settlement of zoospores of the green alga Ulva.

Science.gov (United States)

Grozea, Claudia M; Gunari, Nikhil; Finlay, John A; Grozea, Daniel; Callow, Maureen E; Callow, James A; Lu, Zheng-Hong; Walker, Gilbert C

2009-04-13

Nanopatterned surfaces with hydrophobic and hydrophilic domains were produced using the diblock copolymer polystyrene-block-poly(2-vinyl pyridine) (PS-b-P2VP) and polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA). The PS-b-P2VP diblock copolymer, mixed with the cross-linker benzophenone and spin-coated onto silicon wafers, showed self-assembled cylindrical structures, which were retained after UV treatment for cross-linking. The thin films displayed cylindrical domains after immersion in water. This study shows that pattern retention in water is possible for a long period of time, at least for two weeks in pure water and three weeks in artificial seawater. The PS-b-PMMA diblock showed self-assembled cylindrical structures. PS-b-P2VP and PS-b-PMMA cylindrical patterned surfaces showed reduced settlement of zoospores of the green alga Ulva compared to unpatterned surfaces. The copolymers were investigated using atomic force microscopy and X-ray photoelectron spectroscopy.

Ulva lactuca polysaccharides prevent Wistar rat breast carcinogenesis through the augmentation of apoptosis, enhancement of antioxidant defense system, and suppression of inflammation

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Abd-Ellatef GF

2017-02-01

Full Text Available Gamal-Eldein F Abd-Ellatef,1 Osama M Ahmed,2 Eman S Abdel-Reheim,2 Abdel-Hamid Z Abdel-Hamid,1 1Pharmaceutical and Drug Industries Research Division, Therapeutic Chemistry Department, National Research Centre, Cairo, Egypt; 2Division of Physiology, Department of Zoology, Faculty of Science, Beni-Suef University, Beni-Suef, Egypt Background: Recently, several research studies have been focused on the isolation and function of the polysaccharides derived from different algal species, which revealed multiple biological activities such as antioxidant and antitumor activities. This study assesses the possible breast cancer chemopreventive properties of common seaweeds, sea lettuce, Ulva lactuca (ulvan polysaccharides using in vitro bioassays on human breast cancer cell line (MCF-7 and an in vivo animal model of breast carcinogenesis. Methods: Cytotoxic effect of ulvan polysaccharides on MCF-7 was tested in vitro. For an in vivo investigation, a single dose of 25 mg/kg body weight 7,12-dimethylbenz[a]anthracene (DMBA and ulvan polysaccharides (50 mg/kg body weight every other day for 10 weeks were administered orally to the Wistar rats. Results: Deleterious histopathological alterations in breast tissues including papillary cyst adenoma and hyperplasia of ductal epithelial lining with intraluminal necrotic materials and calcifications were observed in the DMBA-administered group. These lesions were prevented in the DMBA-administered group treated with ulvan polysaccharides. The immunohistochemical sections depicted that the treatment of DMBA-administered rats with ulvan polysaccharides markedly increased the lowered pro-apoptotic protein, p53, and decreased the elevated anti-apoptotic marker, bcl2, expression in the breast tissue. The elevated lipid peroxidation and the suppressed antioxidant enzyme activities in DMBA-administered control were significantly prevented by the treatment with ulvan polysaccharides. The elevated levels of inflammatory

Bioremediation potential, growth and biomass yield of the green seaweed, Ulva lactuca in an integrated marine aquaculture system at the Red Sea coast of Saudi Arabia at different stocking densities and effluent flow rates

KAUST Repository

Al-Hafedh, Yousef S.

2014-03-19

Growth, production and biofiltration rates of seaweed, Ulva lactuca were investigated at two stocking densities (3 kg and 6 kg m-2) and two effluent flow rates (5.4 and 10.8 m3 day-1) to optimize an integrated mariculture system at Saudi Red Sea coast. effluents from fish-rearing tank, stocked with 200 kg fish (Oreochromis spilurus), fed to six seaweed tanks via sedimentation tank. Fish growth (weight gain 1.75 g fish day-1), net production (NP, 10.16 kg m-3) and survival (94.24%) were within acceptable limits. Ulva showed significantly higher (F = 62.62, d.f. 3, 35; P < 0.0001) specific growth rates at lower density compared with higher density and under high flow versus low flow (SGR = 5.78% vs. 2.55% at lower flow and 10.60% vs. 6.26% at higher flow). Biomass yield of Ulva at low- and high-stocking densities (111.11 and 83.2 g wet wt m-2 day-1, respectively) at low flow and (267.44 and 244.19 g wet wt m-2 day-1, respectively) at high flow show that high flow rate and lower density favoured growth. Removal rates of total ammonia nitrogen (TAN) (0.26-0.31 g m-2 day-1) and phosphate phosphorus (0.32-0.41 g m-2 day-1) by U. lactuca were not significantly different (F = 1.9, d.f. 3, 59; P = 0.1394 for TAN and F = 0.29, d.f. 3, 59; P = 0.8324 for phosphates) at both the flow rates and stocking densities. Results show that the effluent flow rate has significant impact over the performance of the seaweed than stocking density.

Bioremediation potential, growth and biomass yield of the green seaweed, Ulva lactuca in an integrated marine aquaculture system at the Red Sea coast of Saudi Arabia at different stocking densities and effluent flow rates

KAUST Repository

Al-Hafedh, Yousef S.; Alam, Aftab; Buschmann, Alejandro H.

2014-01-01

Growth, production and biofiltration rates of seaweed, Ulva lactuca were investigated at two stocking densities (3 kg and 6 kg m-2) and two effluent flow rates (5.4 and 10.8 m3 day-1) to optimize an integrated mariculture system at Saudi Red Sea coast. effluents from fish-rearing tank, stocked with 200 kg fish (Oreochromis spilurus), fed to six seaweed tanks via sedimentation tank. Fish growth (weight gain 1.75 g fish day-1), net production (NP, 10.16 kg m-3) and survival (94.24%) were within acceptable limits. Ulva showed significantly higher (F = 62.62, d.f. 3, 35; P < 0.0001) specific growth rates at lower density compared with higher density and under high flow versus low flow (SGR = 5.78% vs. 2.55% at lower flow and 10.60% vs. 6.26% at higher flow). Biomass yield of Ulva at low- and high-stocking densities (111.11 and 83.2 g wet wt m-2 day-1, respectively) at low flow and (267.44 and 244.19 g wet wt m-2 day-1, respectively) at high flow show that high flow rate and lower density favoured growth. Removal rates of total ammonia nitrogen (TAN) (0.26-0.31 g m-2 day-1) and phosphate phosphorus (0.32-0.41 g m-2 day-1) by U. lactuca were not significantly different (F = 1.9, d.f. 3, 59; P = 0.1394 for TAN and F = 0.29, d.f. 3, 59; P = 0.8324 for phosphates) at both the flow rates and stocking densities. Results show that the effluent flow rate has significant impact over the performance of the seaweed than stocking density.

Facile green synthesis of zinc oxide nanoparticles using Ulva lactuca seaweed extract and evaluation of their photocatalytic, antibiofilm and insecticidal activity.

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Ishwarya, Ramachandran; Vaseeharan, Baskaralingam; Kalyani, Subramanian; Banumathi, Balan; Govindarajan, Marimuthu; Alharbi, Naiyf S; Kadaikunnan, Shine; Al-Anbr, Mohammed N; Khaled, Jamal M; Benelli, Giovanni

2018-01-01

The bioactivity of semiconductor nanocomplexes has been poorly studied in the field of pesticide science. In this research, the synthesis of zinc nanoparticles was accomplished through new effortless green chemistry process, using the Ulva lactuca seaweed extract as a reducing and capping agent. The production of U. lactuca-fabricated ZnO nanoparticles (Ul-ZnO Nps) was characterized by powder X-ray diffraction (XRD), UV-visible, Fourier transform infrared (FTIR) spectroscopy, selected area electron diffraction (SAED) analysis and transmission electron microscopy (TEM). The U. lactuca-fabricated ZnO NPs were tested for their photodegradative action against organic dyes, as well as for antibiofilm and larvicidal activities. The UV visible absorbance spectrum of Ul-ZnO NPs exhibited the absorbance band at 325nm and TEM highlighted average crystallite sizes of nanoparticles of 10-50nm. Methylene blue (MB) dye was efficiently corrupted under sunlight in presence of Ul-ZnO NPs. Excellent bactericidal activity was shown by the Ul-ZnO Nps on Gram positive (Bacillus licheniformis and Bacillus pumilis) and Gram negative (Escherichia coliand Proteus vulgaris) bacteria. High antibiofilm potential was noted under both dark and sunlight conditions. The impact of a single treatment with Ul-ZnO NPs on biofilm architecture was also analyzed by confocal laser scanning microscopy (CLSM) on both Gram positive and Gram negative bacteria. Moreover, Ul-ZnO NPs led to 100% mortality of Aedes aegypti fourth instar larvae at the concentration of 50μg/ml within 24h. The effects of ZnO nanoparticle-based treatment on mosquito larval morphology and histology were monitored. Overall, based on our results, we believe that the synthesis of multifunctional Ul-ZnO Nps using widely available seaweed products can be promoted as a potential eco-friendly option to chemical methods currently used for nanosynthesis of antimicrobials and insecticides. Copyright © 2017 Elsevier B.V. All rights reserved.

Analgesic and anti-inflammatory actions on bradykinin route of a polysulfated fraction from alga Ulva lactuca.

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de Araújo, Ianna Wivianne Fernandes; Rodrigues, José Ariévilo Gurgel; Quinderé, Ana Luíza Gomes; Silva, Jane de Fátima Teixeira; Maciel, Gabrielle de Freitas; Ribeiro, Natássia Albuquerque; de Sousa Oliveira Vanderlei, Edfranck; Ribeiro, Kátia Alves; Chaves, Hellíada Vasconcelos; Pereira, Karuza Maria Alves; Bezerra, Mirna Marques; Benevides, Norma Maria Barros

2016-11-01

We investigated structural features of polysaccharides from Ulva lactuca and their effects on the classical models of nociception and inflammation. Crude extract was obtained by enzymatic digestion and isolated by ion exchange chromatography on DEAE-cellulose. The fraction with higher yield was used in the tests (SP-Ul). Swiss mice received SP-Ul (1, 3 or 9mg/kg; i.v.), 30min prior to injection of 0.8%-acetic acid or 1%-formalin or prior to a thermal stimulus. At same doses, SP-Ul was tested on Wistar rats on paw edema elicited by different irritants (carrageenan, dextran, bradykinin, histamine or serotonin). The results of infrared characterization indicated the presence of hydroxyl groups, sulfate, uronic acid and glycosidic linkages in all SP fractions spectrums. SP-Ul decreased significantly the antinociception in response to acetic acid or formalin (second phase), but not in the hot-plate test, suggesting that its analgesia occurs through a peripheral mechanism. SP-Ul did not reduce carrageenan-induced paw edema as supported by both histological and myeloperoxidase activity assessments. However, SP-Ul (1mg/kg; s.c.) reduced dextran-elicited edema, showing vascular anti-inflammatory effect, with bradykinin as major target because it did not reduce histamine- and serotonin-induced paw edemas. Therefore, SP-Ul acts on bradykinin pathway in its antinociceptive and anti-inflammatory responses. Copyright © 2016 Elsevier B.V. All rights reserved.

Isolation, structure, and surfactant properties of polysaccharides from Ulva lactuca L. from South China Sea.

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Tian, Hua; Yin, Xueqiong; Zeng, Qinghuan; Zhu, Li; Chen, Junhua

2015-08-01

Two polysaccharides (ULP1 and ULP2) were isolated through ultrasonic-assisted extraction from green seaweed Ulva lactuca L. which was collected from the South China Sea. The highest yield of 17.57% was obtained under the conditions of 2% NaOH, 90 °C, material/water mass ratio 1:80, liquid extraction 5h and subsequent ultrasound-assisted extraction 1h. The structure of ULPs were characterized with periodate oxidation followed by Smith degradation, (1)H NMR, (13)C NMR spectroscopy, FTIR, and GPC. The molecular weights of ULP1 and ULP2 were 189 kDa and 230 kDa, respectively. The structural characteristics of ULP1 and ULP2 were quite similar. They were composed of rhamnose, xylose, glucose, and glucuronic acid. The content of rhamnose, xylose, glucose, glucuronic acid, sulfate was 51.2%, 12.3%, 20.1%, 16.4%, 12.0% for ULP1, respectively, and 60.8%, 14.2%, 8.2%, 16.8%, 26.8%, respectively, for ULP2. Both ULP1 and ULP2 showed good surface activity. 5 mg/mL ULP1 (2.62×10(-2) mmol/L) decreased the water surface tension to 51.63 mN/m. The critical micellar concentration of ULP1 and ULP2 was 1.01 mg/mL (5.3×10(-3) mmol/L) and 1.14 mg/mL (5.0×10(-3) mmol/L), respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

Protective effect of Ulva lactuca extract during hepatic cold preservation in rats.

Science.gov (United States)

Ferchichi, Henda; Bacha, Sarra; Kourda, Nadia; Melaouhia, Salma; Gaies, Emna; Lakhal, Mohamed; Klouz, Anis; Trabelsi, S; Salouage, Issam

2016-04-01

from the green seaweed Ulva lactuca to improve the conservation solution of organs against the hepatic effects of ischemia.

Especies de Ulva del Golfo San Jorge, Patagonia Argentina: variaciones bioquímicas estacionales - espaciales y su relación con la producción de metabolitos bioactivos

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Analía Verónica Uhrich

Full Text Available Objetivos: Investigar especies de Ulva del Golfo San Jorge, Patagonia Argentina, integrando aspectos bioquímicos, actividad biológica y variaciones estacionales/habitacionales que permitan determinar su potencial aplicación en Salud. Métodos: Las algas se colectaron estacionalmente en playas con y sin contaminación antrópica; se secaron, molieron y extrajeron con etanol. Los extractos se fraccionaron mediante solventes de distinta polaridad. Cada fracción fue caracterizada mediante reacciones químicas cualitativas y cromatografía. Las fracciones ricas en flavonoides se analizaron por HPLC-DAD y los lípidos, por TLC. La actividad biológica se ensayó mediante el test de citotoxicidad de Artemia salina, inhibición de la elongación radicular, inhibición de la xantino oxidasa, actividad antioxidante y antibacteriana. Resultados: Se identificaron Ulva rigida y Ulva lactuca. Ambas evidenciaron flavonoides, taninos, quinonas, lípidos, carbohidratos, esteroides. Los flavonoides resultaron mayoritarios en U. rigida (otoño e invierno y en U. lactuca (primavera e invierno, destacándose kayaflavona. Se detectaron alcaloides en Ulva rigida (verano. Los lípidos fueron mayoritarios en verano; U. lactuca en invierno mostró monogalactosildiacilglicérido y en otoño, digalactosilacilglicérido y fosfatidilcolina. La actividad inhibitoria de la elongación radicular, que presume actividad antitumoral, fue importante y dosis dependiente, destacándose U. rigida de otoño y primavera (DE50= 480 y 520 µg/ml, respectivamente. Las demás bioactividades resultaron escasas o negativas. Conclusiones: Las variaciones metabólicas observadas muestran la importancia de considerar las condiciones espacio - temporales al planificar una colecta de ejemplares para su estudio y/o aplicación. Este primer análisis integral de especies de Ulva de la Patagonia Argentina, evidencia su potencialidad como antitumoral.

Zoospore exudates from Phytophthora nicotianae affect immune responses in Arabidopsis.

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Kong, Ping; McDowell, John M; Hong, Chuanxue

2017-01-01

Zoospore exudates play important roles in promoting zoospore communication, homing and germination during plant infection by Phytophthora. However, it is not clear whether exudates affect plant immunity. Zoospore-free fluid (ZFF) and zoospores of P. nicotianae were investigated comparatively for effects on resistance of Arabidopsis thaliana Col-0 and mutants that affect signaling mediated by salicylic acid (SA) and jasmonic acid (JA): eds16 (enhanced disease susceptibility16), pad4 (phytoalexin deficient4), and npr1 (nonexpressor of pathogenesis-related genes1). Col-0 attracted more zoospores and had severe tissue damage when flooded with a zoospore suspension in ZFF. Mutants treated with ZFF alone developed disease symptoms similar to those inoculated with zoospores and requirements of EDS16 and PAD4 for plant responses to zoospores and the exudates was apparent. Zoospore and ZFFs also induced expression of the PR1 and PDF1.2 marker genes for defense regulated by SA and JA, respectively. However, ZFF affected more JA defense signaling, down regulating PR1 when SA signaling or synthesis is deficient, which may be responsible for Arabidopsis mutant plants more susceptible to infection by high concentration of P. nicotianae zoospores. These results suggest that zoospore exudates can function as virulence factors and inducers of plant immune responses during plant infection by Phytophthora.

Zoospore exudates from Phytophthora nicotianae affect immune responses in Arabidopsis.

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Ping Kong

Full Text Available Zoospore exudates play important roles in promoting zoospore communication, homing and germination during plant infection by Phytophthora. However, it is not clear whether exudates affect plant immunity. Zoospore-free fluid (ZFF and zoospores of P. nicotianae were investigated comparatively for effects on resistance of Arabidopsis thaliana Col-0 and mutants that affect signaling mediated by salicylic acid (SA and jasmonic acid (JA: eds16 (enhanced disease susceptibility16, pad4 (phytoalexin deficient4, and npr1 (nonexpressor of pathogenesis-related genes1. Col-0 attracted more zoospores and had severe tissue damage when flooded with a zoospore suspension in ZFF. Mutants treated with ZFF alone developed disease symptoms similar to those inoculated with zoospores and requirements of EDS16 and PAD4 for plant responses to zoospores and the exudates was apparent. Zoospore and ZFFs also induced expression of the PR1 and PDF1.2 marker genes for defense regulated by SA and JA, respectively. However, ZFF affected more JA defense signaling, down regulating PR1 when SA signaling or synthesis is deficient, which may be responsible for Arabidopsis mutant plants more susceptible to infection by high concentration of P. nicotianae zoospores. These results suggest that zoospore exudates can function as virulence factors and inducers of plant immune responses during plant infection by Phytophthora.

A surface complexation model of YREE sorption on Ulva lactuca in 0.05-5.0 M NaCl solutions

Science.gov (United States)

Zoll, Alison M.; Schijf, Johan

2012-11-01

We present distribution coefficients, log iKS, for the sorption of yttrium and the rare earth elements (YREEs) on BCR-279, a dehydrated tissue homogenate of a marine macroalga, Ulva lactuca, resembling materials featured in chemical engineering studies aimed at designing renewable biosorbents. Sorption experiments were conducted in NaCl solutions of different ionic strength (0.05, 0.5, and 5.0 M) at T = 25 °C over the pH range 2.7-8.5. Distribution coefficients based on separation of the dissolved and particulate phase by conventional filtration (3 kDa) using an existing pH-dependent model. Colloid-corrected values were renormalized to free-cation concentrations by accounting for YREE hydrolysis and chloride complexation. At each ionic strength, the pH dependence of the renormalized values is accurately described with a non-electrostatic surface complexation model (SCM) that incorporates YREE binding to three monoprotic functional groups, previously characterized by alkalimetric titration, as well as binding of YREE-hydroxide complexes (MOH2+) to the least acidic one (pKa ∼ 9.5). In non-linear regressions of the distribution coefficients as a function of pH, each pKa was fixed at its reported value, while stability constants of the four YREE surface complexes were used as adjustable parameters. Data for a single fresh U. lactuca specimen in 0.5 M NaCl show generally the same pH-dependent behavior but a lower degree of sorption and were excluded from the regressions. Good linear free-energy relations (LFERs) between stability constants of the YREE-acetate and YREE-hydroxide solution complex and surface complexes with the first and third functional group, respectively, support their prior tentative identifications as carboxyl and phenol. A similar confirmation for the second group is precluded by insufficient knowledge of the stability of YREE-phosphate complexes and a perceived lack of YREE binding in 0.05 M NaCl; this issue awaits further study. The results

Rhamnolipids as platform molecules for production of potential anti-zoospore agrochemicals.

Science.gov (United States)

Miao, Shida; Dashtbozorg, Soroosh Soltani; Callow, Nicholas V; Ju, Lu-Kwang

2015-04-08

Rhamnolipid biosurfactants have potential applications in the control of zoosporic plant pathogens. However, rhamnolipids have not been closely investigated for the anti-zoospore mechanism or for developing new anti-zoospore chemicals. In this study, RhL-1 and RhL-3 groups of rhamnolipids were used to generate the corresponding RhL-2 and RhL-4 groups and the free diacids. Conversion of RhL-3 to RhL-1 was also accomplished in vitro with cellobiase as the catalyst. The anti-zoospore effects of RhL-1-RhL-4 and the diacids were investigated with zoospores of Phytophthora sojae. For RhL-1-RhL-4, approximately 20, 30, 40, and 40 mg/L, respectively, were found to be the lowest concentrations required to stop movement of all zoospores, which indicates that the anti-zoospore effect remains strong even after RhL-1 and RhL-3 are hydrolyzed into RhL-2 and RhL-4. The free diacids required a significantly higher critical concentration of about 125 mg/L. Rhamnose can be obtained as a co-product.

Bioactive compounds and antifungal activity of three different seaweed species Ulva lactuca, Sargassum tenerrimum and Laurencia obtusa collected from Okha coast, Western India

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Megha Barot

2016-04-01

Full Text Available Objective: To evaluate bioactive compounds responsible for antifungal activity from seaweeds of Okha coast, Western India. Methods: Each species were extracted with different solvents with increasing polarity: hexane, ethyl acetate, chloroform and methanol using Soxhlet apparatus. The antifungal activity was determined by agar diffusion plate method by using fluconazole, ketoconazole and amphotericin B as standards. Gas chromatography-mass spectrometer analysis was done for identification of bioactive compounds present in crude extract. Results: The gas chromatography-mass spectrometer analysis of all the extracts revealed the presence of steroids, fatty acids and esters compounds. Among the three species, the maximum crude extract yield (53.46% and the largest inhibition zone (36 mm were recorded in methanol extract of Ulva lactuca, whereas the minimum crude extract yield and inhibition zone were recorded in chloroform extract of the same species as 0.5% and 10 mm, respectively. Methanol and ethyl acetate extract showed the maximum antifungal activity and the major important compounds like steroids, fatty acids and esters were detected with higher amount in all the extracts. Conclusions: The present study revealed that the different seaweed extracts showed moderate to significant antifungal activity against the strains tested as compared with the standard fungicides, and polar solvents methanol and ethyl acetate were comparatively efficient for extraction of different metabolites that are responsible for antifungal activity.

Toxic effects of imidazolium ionic liquids on the green seaweed Ulva lactuca: oxidative stress and DNA damage.

Science.gov (United States)

Kumar, Manoj; Trivedi, Nitin; Reddy, C R K; Jha, Bhavanath

2011-11-21

The green credentials of ionic liquids (ILs) are being increasingly questioned due to the growing evidence of their toxicity to aquatic ecosystems, although the mechanisms of toxicity are unknown. This study provides insights into the mechanism of toxicity and biological effects of 1-alkyl-3-methylimidazolium bromide [C(n)mim]Br (n = 4 to 16) on the marine macroalga Ulva lactuca. The cell viability of this alga during IL exposure was found to be negatively correlated to the chain length of the alkyl group. The IL ([C(12)mim]Br) exposure triggers the generation of reactive oxygen species (ROS viz. O(2)(•-), H(2)O(2), and OH(•)), damage of the membrane and DNA, and inhibition of antioxidant systems in the alga. The enhanced production of ROS and lipid peroxidation in the alga subjected to LC(50) concentration for 4 days was largely attributed to lipoxygenase (LOX) activity coupled with the induction of two LOX isoforms (~80 kDa and ~55 kDa). Pretreatment of the algal thallus with enzyme inhibitors such as diphenylene iodonium, sodium azide, cantharidin, and oxadiazoloquinoxalin-1-one, prior to [C(12)mim]Br exposure showed the regulation of ROS by the activation of membrane bound NADPH-oxidase and cytochrome oxidase. The IL exposure resulted in the accumulation of n-3 and n-6 fatty acids at 0.5 LC(50) concentration indicating the induction of desaturase enzymes. Furthermore, antioxidant enzyme activities such as superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR) were enhanced by 1.3-2.0-fold, while glutathione peroxidase (GSH-Px) diminished, together with a higher regeneration rate of reduced ascorbate and glutathione. The isoforms of antioxidant enzymes, namely, Mn-SOD (~85 kDa), APX (~125 and 45 kDa), and GR (~135 kDa) regulated differentially to IL exposure. The comet assay performed for the first time for seaweeds revealed the significant induction of DNA damage (>50-70% increase in % tail DNA over control) in alga exposed

Copper (II) Lead (II) and Zinc (II) reduce growth and zoospore release in four zoosporic true fungi from soils of NSW, Australia

DEFF Research Database (Denmark)

Henderson, Linda; Pilgaard, Bo; Gleason, Frank

2015-01-01

This study examined the responses of a group of four zoosporic true fungi isolated from soils in NSW Australia, to concentrations of toxic metals in the laboratory that may be found in polluted soils. All isolates showed greatest sensitivity to Cu and least sensitivity to Pb. All isolates showed ...... in 60 ppm Cu. If these metals cause similar effects in the field, Cu, Pb and Zn contamination of NSW soils is likely to reduce biomass of zoosporic true fungi. Loss of the fungi may reduce the rate of mineralisation of soil organic matter.......This study examined the responses of a group of four zoosporic true fungi isolated from soils in NSW Australia, to concentrations of toxic metals in the laboratory that may be found in polluted soils. All isolates showed greatest sensitivity to Cu and least sensitivity to Pb. All isolates showed...

Fungal infection intensity and zoospore output of Atelopus zeteki, a potential acute chytrid supershedder.

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Graziella V Direnzo

Full Text Available Amphibians vary in their response to infection by the amphibian-killing chytrid fungus, Batrachochytrium dendrobatidis (Bd. Highly susceptible species are the first to decline and/or disappear once Bd arrives at a site. These competent hosts likely facilitate Bd proliferation because of ineffective innate and/or acquired immune defenses. We show that Atelopus zeteki, a highly susceptible species that has undergone substantial population declines throughout its range, rapidly and exponentially increases skin Bd infection intensity, achieving intensities that are several orders of magnitude greater than most other species reported. We experimentally infected individuals that were never exposed to Bd (n = 5 or previously exposed to an attenuated Bd strain (JEL427-P39; n = 3. Within seven days post-inoculation, the average Bd infection intensity was 18,213 zoospores (SE: 9,010; range: 0 to 66,928. Both average Bd infection intensity and zoospore output (i.e., the number of zoospores released per minute by an infected individual increased exponentially until time of death (t50 = 7.018, p<0.001, t46 = 3.164, p = 0.001, respectively. Mean Bd infection intensity and zoospore output at death were 4,334,422 zoospores (SE: 1,236,431 and 23.55 zoospores per minute (SE: 22.78, respectively, with as many as 9,584,158 zoospores on a single individual. The daily percent increases in Bd infection intensity and zoospore output were 35.4% (SE: 0.05 and 13.1% (SE: 0.04, respectively. We also found that Bd infection intensity and zoospore output were positively correlated (t43 = 3.926, p<0.001. All animals died between 22 and 33 days post-inoculation (mean: 28.88; SE: 1.58. Prior Bd infection had no effect on survival, Bd infection intensity, or zoospore output. We conclude that A. zeteki, a highly susceptible amphibian species, may be an acute supershedder. Our results can inform epidemiological models to estimate Bd outbreak probability, especially as they relate

Ulva Lactuca

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Cristina Peri Rossi

2015-12-01

Full Text Available She looked loathingly at the spoon. It was a metal spoon, dark, with a small engraving on its handle – a sharp taste. “Open your mouth, slowly, eaaaasy, like a little birdie in its nest,” he said, bringing the spoon to her mouth. He hated spoons; they had seemed despicable little things since he was small. Why did he now find himself having to wield it, full of soup, having to usher it now into this young child’s mouth, as his parents had done to him, as surely as his parents’ parents had also done? If they even had spoons then, if some fool had already invented them. He had to find himself an encyclopedia and figure out when the first spoon had been forged; he had to get his hands on an encyclopedia, a source of infinite knowledge by which he might survive. Spoon: A piece of silverware with a concave scoop at its end; typically used for carrying liquids to the mouth.

Bacteria-induced morphogenesis of Ulva intestinalis and Ulva mutabilis (Chlorophyta): a contribution to the lottery theory.

Science.gov (United States)

Ghaderiardakani, Fatemeh; Coates, Juliet C; Wichard, Thomas

2017-08-01

The green marine macroalgae of the class Ulvophyceae (Ulvophytes) are common algae distributed worldwide particularly in intertidal areas, which play a key role in aquatic ecosystems. They are potentially valuable resources for food, animal feed and fuel but can also cause massive nuisance blooms. Members of Ulvaceae, like many other seaweeds, harbour a rich diversity of epiphytic bacteria with functions related to host growth and morphological development. In the absence of appropriate bacterially derived signals, germ cells of the genus Ulva develop into 'atypical' colonies consisting of undifferentiated cells with abnormal cell walls. This paper examines the specificity of bacteria-induced morphogenesis in Ulva, by cross-testing bacteria isolated from several Ulva species on two Ulva species, the emerging model system Ulva mutabilis and the prominent biofouler species Ulva intestinalis. We show that pairs of bacterial strains isolated from species other than U. mutabilis and U. intestinalis can fully rescue axenic plantlets generated either from U. mutabilis or U. intestinalis gametes. This laboratory-based study demonstrates that different compositions of microbial communities with similar functional characteristics can enable complete algal morphogenesis and thus supports the 'competitive lottery' theory for how symbiotic bacteria drive algal development. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Seaweed extracts and unsaturated fatty acid constituents from the green alga Ulva lactuca as activators of the cytoprotective Nrf2-ARE pathway.

Science.gov (United States)

Wang, Rui; Paul, Valerie J; Luesch, Hendrik

2013-04-01

Increased amounts of reactive oxygen species (ROS) have been implicated in many pathological conditions, including cancer. The major machinery that the cell employs to neutralize excess ROS is through the activation of the antioxidant-response element (ARE) that controls the activation of many phase II detoxification enzymes. The transcription factor that recognizes the ARE, Nrf2, can be activated by a variety of small molecules, most of which contain an α,β-unsaturated carbonyl system. In the pursuit of chemopreventive agents from marine organisms, we built, fractionated, and screened a library of 30 field-collected eukaryotic algae from Florida. An edible green alga, Ulva lactuca, yielded multiple active fractions by ARE-luciferase reporter assay. We isolated three monounsaturated fatty acid (MUFA) derivatives as active components, including a new keto-type C18 fatty acid (1), the corresponding shorter chain C16 acid (2), and an amide derivative (3) of the C18 acid. Their chemical structures were elucidated by NMR and mass spectrometry. All three contain the conjugated enone motif between C7 and C9, which is thought to be responsible for the ARE activity. Subsequent biological studies focused on 1, the most active and abundant ARE activator isolated. C18 acid 1 induced the expression of ARE-regulated cytoprotective genes, including NAD(P)H:quinone oxidoreductase 1, heme oxygenase 1, thioredoxin reductase 1, both subunits of the glutamate-cysteine ligase (catalytic subunit and modifier subunit), and the cystine/glutamate exchange transporter, in IMR-32 human neuroblastoma cells. Its cellular activity requires the presence of Nrf2 and PI3K function, based on RNA interference and pharmacological inhibitor studies, respectively. Treatment with 1 led only to Nrf2 activation, and not the increase in production of NRF2 mRNA. To test its ARE activity and cytoprotective potential in vivo, we treated mice with a single dose of a U. lactuca fraction that was enriched with

Strong Endemism of bloom-forming tubular Ulva in Indian West Coast, with description of Ulva paschima Sp. Nov. (Ulvales, Chlorophyta).

Science.gov (United States)

Bast, Felix; John, Aijaz Ahmad; Bhushan, Satej

2014-01-01

Ulva intestinalis and Ulva compressa are two bloom-forming morphologically-cryptic species of green seaweeds widely accepted as cosmopolitan in distribution. Previous studies have shown that these are two distinct species that exhibit great morphological plasticity with changing seawater salinity. Here we present a phylogeographic assessment of tubular Ulva that we considered belonging to this complex collected from various marine and estuarine green-tide occurrences in a ca. 600 km stretch of the Indian west coast. Maximum Likelihood and Bayesian Inference phylogenetic reconstructions using ITS nrDNA revealed strong endemism of Indian tubular Ulva, with none of the Indian isolates forming part of the already described phylogenetic clades of either U. compressa or U. intestinalis. Due to the straightforward conclusion that Indian isolates form a robust and distinct phylogenetic clade, a description of a new bloom-forming species, Ulva paschima Bast, is formally proposed. Our phylogenetic reconstructions using Neighbor-Joining method revealed evolutionary affinity of this new species with Ulva flexuosa. This is the first molecular assessment of Ulva from the Indian Subcontinent.

Seaweed extracts and unsaturated fatty acid constituents from the green alga Ulva lactuca as activators of the cytoprotective Nrf2–ARE pathway

Science.gov (United States)

Wang, Rui; Paul, Valerie J.; Luesch, Hendrik

2013-01-01

Increased amounts of reactive oxygen species (ROS) have been implicated in many pathological conditions, including cancer. The major machinery that the cell employs to neutralize excess ROS is through the activation of the antioxidant-response element (ARE) that controls the activation of many phase II detoxification enzymes. The transcription factor that recognizes the ARE, Nrf2, can be activated by a variety of small molecules, most of which contain an α,β-unsaturated carbonyl system. In the pursuit of chemopreventive agents from marine organisms, we built, fractionated, and screened a library of 30 field-collected eukaryotic algae from Florida. An edible green alga, Ulva lactuca, yielded multiple active fractions by ARE–luciferase reporter assay. We isolated three monounsaturated fatty acid (MUFA) derivatives as active components, including a new keto-type C18 fatty acid (1), the corresponding shorter chain C16 acid (2), and an amide derivative (3) of the C18 acid. Their chemical structures were elucidated by NMR and mass spectrometry. All three contain the conjugated enone motif between C7 and C9, which is thought to be responsible for the ARE activity. Subsequent biological studies focused on 1, the most active and abundant ARE activator isolated. C18 acid 1 induced the expression of ARE-regulated cytoprotective genes, including NAD(P)H:quinone oxidoreductase 1, heme oxygenase 1, thioredoxin reductase 1, both subunits of the glutamate–cysteine ligase (catalytic subunit and modifier subunit), and the cystine/glutamate exchange transporter, in IMR-32 human neuroblastoma cells. Its cellular activity requires the presence of Nrf2 and PI3K function, based on RNA interference and pharmacological inhibitor studies, respectively. Treatment with 1 led only to Nrf2 activation, and not the increase in production of NRF2 mRNA. To test its ARE activity and cytoprotective potential in vivo, we treated mice with a single dose of a U. lactuca fraction that was enriched

Zoosporic Tolerance to pH Stress and Its Implications for Phytophthora Species in Aquatic Ecosystems▿

OpenAIRE

Kong, Ping; Moorman, Gary W.; Lea-Cox, John D.; Ross, David S.; Richardson, Patricia A.; Hong, Chuanxue

2009-01-01

Phytophthora species, a group of destructive plant pathogens, are commonly referred to as water molds, but little is known about their aquatic ecology. Here we show the effect of pH on zoospore survival of seven Phytophthora species commonly isolated from irrigation reservoirs and natural waterways and dissect zoospore survival strategy. Zoospores were incubated in a basal salt liquid medium at pH 3 to 11 for up to 7 days and then plated on a selective medium to determine their survival. The ...

Defective zoospore encystment and suppressed cyst germination of Phytophthora palmivora caused by transient leaching treatments

NARCIS (Netherlands)

Dijksterhuis, J; Deacon, J W

2003-01-01

The behaviour of encysting zoospores of Phytophthora palmivora during leaching conditions was studied. Zoospores encysted and germinated successfully on polycarbonate membranes after mechanical agitation. Transient (10 min) leaching treatments with nutrient-free buffer underneath the membranes

A novel method for efficient and abundant production of Phytophthora brassicae zoospores on Brussels sprout leaf discs

Directory of Open Access Journals (Sweden)

Govers Francine

2009-08-01

Full Text Available Abstract Background Phytophthora species are notorious oomycete pathogens that cause diseases on a wide range of plants. Our understanding how these pathogens are able to infect their host plants will benefit greatly from information obtained from model systems representative for plant-Phytophthora interactions. One attractive model system is the interaction between Arabidopsis and Phytophthora brassicae. Under laboratory conditions, Arabidopsis can be easily infected with mycelial plugs as inoculum. In the disease cycle, however, sporangia or zoospores are the infectious propagules. Since the current P. brassicae zoospore isolation methods are generally regarded as inefficient, we aimed at developing an alternative method for obtaining high concentrations of P. brassicae zoospores. Results P. brassicae isolates were tested for pathogenicity on Brussels sprout plants (Brassica oleracea var. gemmifera. Microscopic examination of leaves, stems and roots infected with a GFP-tagged transformant of P. brassicae clearly demonstrated the susceptibility of the various tissues. Leaf discs were cut from infected Brussels sprout leaves, transferred to microwell plates and submerged in small amounts of water. In the leaf discs the hyphae proliferated and abundant formation of zoosporangia was observed. Upon maturation the zoosporangia released zoospores in high amounts and zoospore production continued during a period of at least four weeks. The zoospores were shown to be infectious on Brussels sprouts and Arabidopsis. Conclusion The in vitro leaf disc method established from P. brassicae infected Brussels sprout leaves facilitates convenient and high-throughput production of infectious zoospores and is thus suitable to drive small and large scale inoculation experiments. The system has the advantage that zoospores are produced continuously over a period of at least one month.

Copper (II) lead (II), and zinc (II) reduce growth and zoospore release in four zoosporic true fungi from soils of NSW, Australia.

Science.gov (United States)

Henderson, Linda; Pilgaard, Bo; Gleason, Frank H; Lilje, Osu

2015-07-01

This study examined the responses of a group of four zoosporic true fungi isolated from soils in NSW Australia, to concentrations of toxic metals in the laboratory that may be found in polluted soils. All isolates showed greatest sensitivity to Cu and least sensitivity to Pb. All isolates showed significant reduction in growth at 60 ppm (0.94 mmol m(-3)) for Cu, while three declined significantly at 60 ppm (0.92 mmol m(-3)) Zn. The growth of two isolates declined significantly at 100 ppm (0.48 mmol m(-3)) Pb and one at 200 ppm (0.96 mmol m(-3)) Pb. The rate of production of zoospores for all isolates was reduced when sporangia were grown in solid PYG media with 60 ppm Cu. Three isolates significantly declined in production at 60 ppm Zn and three at 100 ppm Pb. All isolates recovered growth after incubation in solid media with 60 ppm Zn or 100 ppm Pb. Two isolates did not recover growth after incubation in 60 ppm Cu. If these metals cause similar effects in the field, Cu, Pb, and Zn contamination of NSW soils is likely to reduce biomass of zoosporic true fungi. Loss of the fungi may reduce the rate of mineralisation of soil organic matter. Copyright © 2015 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

The green seaweed Ulva: A model system to study morphogenesis

Directory of Open Access Journals (Sweden)

Thomas eWichard

2015-02-01

Full Text Available Green macroalgae, mostly represented by the Ulvophyceae, the main multicellular branch of the Chlorophyceae, constitute important primary producers of marine and brackish coastal ecosystems. Ulva or sea lettuce species are some of the most abundant representatives, being ubiquitous in coastal benthic communities around the world. Nonetheless the genus also remains largely understudied. This review highlights Ulva as an exciting novel model organism for studies of algal growth, development and morphogenesis as well as mutualistic interactions. The key reasons that Ulva is potentially such a good model system are: (i patterns of Ulva development can drive ecologically important events, such as the increasing number of green tides observed worldwide as a result of eutrophication of coastal waters, (ii Ulva growth is symbiotic, with proper development requiring close association with bacterial epiphytes, (iii Ulva is extremely developmentally plastic, which can shed light on the transition from simple to complex multicellularity and (iv Ulva will provide additional information about the evolution of the green lineage.

The green seaweed Ulva: a model system to study morphogenesis.

Science.gov (United States)

Wichard, Thomas; Charrier, Bénédicte; Mineur, Frédéric; Bothwell, John H; Clerck, Olivier De; Coates, Juliet C

2015-01-01

Green macroalgae, mostly represented by the Ulvophyceae, the main multicellular branch of the Chlorophyceae, constitute important primary producers of marine and brackish coastal ecosystems. Ulva or sea lettuce species are some of the most abundant representatives, being ubiquitous in coastal benthic communities around the world. Nonetheless the genus also remains largely understudied. This review highlights Ulva as an exciting novel model organism for studies of algal growth, development and morphogenesis as well as mutualistic interactions. The key reasons that Ulva is potentially such a good model system are: (i) patterns of Ulva development can drive ecologically important events, such as the increasing number of green tides observed worldwide as a result of eutrophication of coastal waters, (ii) Ulva growth is symbiotic, with proper development requiring close association with bacterial epiphytes, (iii) Ulva is extremely developmentally plastic, which can shed light on the transition from simple to complex multicellularity and (iv) Ulva will provide additional information about the evolution of the green lineage.

Stable carbon and nitrogen isotope signatures indicate recovery of marine biota from sewage pollution at Moa Point, New Zealand

International Nuclear Information System (INIS)

Rogers, Karyne M.

2003-01-01

Stable carbon and nitrogen isotopes have been used to assess sewage contamination of a sewage outfall, discharging milli-screened effluent into Moa Point Bay, New Zealand, and monitor the recovery of flora and fauna after the outfall's closure. An initial study characterising the extent of the discharge and the effects on seaweed (Ulva lactuca L.), blue mussels (Mytilus galloprovincialis) and limpets (Cellana denticulata) from the area, showed effects of the sewage discharge on flora and fauna were localised within in the bay. The immediate area surrounding the discharge area was found to contain limited biodiversity, with an abundance of Ulva lactuca, a bright green lettuce-like seaweed, typically found in areas with high nutrient input, limpets and small blue mussels. The nitrogen isotopic signature (δ 15 N) is shown to be a good tracer of sewage pollution in seaweed and associated grazers (i.e. limpets) as a result of the increased contribution of urea and ammonia to seawater nitrogen derived from the effluent. The carbon isotopic signature (δ 13 C) is suggested as a more appropriate sewage tracer for mussels, which filter feed the effluent's particulate organic matter from the water. Lower carbon:nitrogen ratios were found in Ulva lactuca sampled from around the outfall region compared to uncontaminated control sites. However carbon:nitrogen ratios do not vary significantly amongst shellfish species. After closure, monitoring continued for 9 months and showed that the carbon and nitrogen isotopic signatures of algae (Ulva lactuca L.) returned to similar control site levels within 3 months. Limpet and blue mussels (Cellana denticulata and Mytilus galloprovincialis) showed slower recovery times than the Ulva lactuca, with detectable levels of the sewage-derived carbon and nitrogen remaining in the animal's tissue for up to 9 months

Stable carbon and nitrogen isotope signatures indicate recovery of marine biota from sewage pollution at Moa Point, New Zealand

Energy Technology Data Exchange (ETDEWEB)

Rogers, Karyne M

2003-07-01

Stable carbon and nitrogen isotopes have been used to assess sewage contamination of a sewage outfall, discharging milli-screened effluent into Moa Point Bay, New Zealand, and monitor the recovery of flora and fauna after the outfall's closure. An initial study characterising the extent of the discharge and the effects on seaweed (Ulva lactuca L.), blue mussels (Mytilus galloprovincialis) and limpets (Cellana denticulata) from the area, showed effects of the sewage discharge on flora and fauna were localised within in the bay. The immediate area surrounding the discharge area was found to contain limited biodiversity, with an abundance of Ulva lactuca, a bright green lettuce-like seaweed, typically found in areas with high nutrient input, limpets and small blue mussels. The nitrogen isotopic signature ({delta}{sup 15}N) is shown to be a good tracer of sewage pollution in seaweed and associated grazers (i.e. limpets) as a result of the increased contribution of urea and ammonia to seawater nitrogen derived from the effluent. The carbon isotopic signature ({delta}{sup 13}C) is suggested as a more appropriate sewage tracer for mussels, which filter feed the effluent's particulate organic matter from the water. Lower carbon:nitrogen ratios were found in Ulva lactuca sampled from around the outfall region compared to uncontaminated control sites. However carbon:nitrogen ratios do not vary significantly amongst shellfish species. After closure, monitoring continued for 9 months and showed that the carbon and nitrogen isotopic signatures of algae (Ulva lactuca L.) returned to similar control site levels within 3 months. Limpet and blue mussels (Cellana denticulata and Mytilus galloprovincialis) showed slower recovery times than the Ulva lactuca, with detectable levels of the sewage-derived carbon and nitrogen remaining in the animal's tissue for up to 9 months.

Adaption of Ulva pertusa to multiple-contamination of heavy metals and nutrients: Biological mechanism of outbreak of Ulva sp. green tide.

Science.gov (United States)

Ge, Changzi; Yu, Xiru; Kan, Manman; Qu, Chunfeng

2017-12-15

The multiple-contamination of heavy metals and nutrients worsens increasingly and Ulva sp. green tide occurs almost simultaneously. To reveal the biological mechanism for outbreak of the green tide, Ulva pertusa was exposed to seven-day-multiple-contamination. The relation between pH variation (V pH ), Chl a content, ratio of (Chl a content)/(Chl b content) (R chla/chlb ), SOD activity of U. pertusa (A SOD ) and contamination concentration is [Formula: see text] (pcontamination concentrations of seawaters where Ulva sp. green tide occurred and the contamination concentrations set in the present work, U. pertusa can adapt to multiple-contaminations in these waters. Thus, the adaption to multiple-contamination may be one biological mechanism for the outbreak of Ulva sp. green tide. Copyright © 2017 Elsevier Ltd. All rights reserved.

Can fungal zoospores be the source of energy for the rumen protozoa Eudiplodinium maggii?

Science.gov (United States)

Miltko, Renata; Bełżecki, Grzegorz; Kowalik, Barbara; Michałowski, Tadeusz

2014-10-01

Results of our earlier studies showed the ability of ciliates Eudiplodinium maggii to digest and metabolize commercial chitin. The natural source of this polysaccharide in the rumen are fungi. The objectives of present research were to determine the effect of fungal zoospores on the survival and population density of E. maggii to quantify the concentration of chitin in the cells of protozoa and to examine the ability of E. maggii, to ferment chitin of fungal zoospores. The cultivation experiment showed that the survival of protozoa was shorter than 4 days when the culture medium was composed of buffer solution and lyophilized fungal spores. An enrichment of this medium with wheat gluten prolonged the survival of ciliates up to 8 days. The supplementation of the last medium with meadow hay enabled the protozoa to survive for 28 days but a positive effect was observed only during the last 8 days of experiment. The chitin content was 0.27 ng and 0.21-0.35 ng per single zoospore and ciliate, respectively. An increase in the concentration of volatile fatty acids (VFA) was found when protozoa were incubated with zoospores. The production rate of VFA was 46.3 pM/protozoan per h whereas the endogenous production did not exceed 31 pM/protozoan per h. The molar proportion of acetic acid was 77.7% and these of butyric and propionic acids-12.2 and 11.0%, respectively. The obtained results make it evident that carbohydrates present in fungal zoospores were utilized by protozoa in energy yielding processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Green seaweed Ulva as a monitor for pollution in coastal waters

Energy Technology Data Exchange (ETDEWEB)

Levine, H.G.

1983-01-01

Methods have been developed which capitalize on the capacity of Ulva to function as a bioindicator of pollution in coastal waters. Studies have been performed evaluating the growth of both Ulva tissue discs and Ulva germlings as they relate to physical and chemical parameters of the environment. The Ulva tissue disc method for the in situ monitoring of organic load (nitrogen and phosphorus) in coastal waters was demonstrated to be marginally effective. The in situ differential growth reponse of parthenogenetically developed germlings fulfilled the monitoring objective, but multi-faceted environmental considerations introduced complications which reduced the feasibility of the germling deployment method for routine monitoring. The assessment of Ulva as a bioaccumulator was undertaken. Use of Ulva as an in situ sampling device has demonstrated appreciable success. This in situ monitor can provide concentrated samples of environmental pollutants. Analytical techniques have been employed to extract information on trace metals, pesticides, PCBs and other accumulated organohalides. Ulva is a bioacumulator which, by all standards, has much to recommend it. Precedures have been developed to reduce much of the inherent biological varation. Ulva has world-wide occurrence, and is therefore capable of providing a standard for comparison of data. This alga merits consideration as an international monitor for pollutants in the marine environment.

Death by Ulva

Science.gov (United States)

We report on a series of field and laboratory mesocosm experiments where we examined the effects of two levels of decomposing Ulva on Spartina alterniflora growth, soil biogeochemistry, and nitrogen dynamics. Monitoring of porewater revealed rapid mineralization to ammonium from...

Use of the vital stain FUN-1 indicates viability of Phytophthora capsici propagules and can be used to predict maximum zoospore production.

Science.gov (United States)

Lewis Ivey, Melanie L; Miller, Sally A

2014-01-01

The fluorescent vital dye FUN®-1 (2-chloro-4-[2,3-dihydro-3-methyl-{benzo-1,3-thiazol-2-yl}-methylidene]-1-phenylquinolinium iodide) was evaluated as a tool to assess Phytophthora capsici sporangia and zoospore metabolic activity and viability. Under aerobic conditions, mycelia, sporangia and zoospores cultured on agar medium and stained with FUN-1 exhibited red fluorescent cylindrical intravacuolar structures (CIVS) that were clearly visible at 100× magnification. Encysted zoospores did not exhibit CIVS after exposure to FUN-1 dye. Over 7 d there was a significant reduction in the percent of sporangia containing CIVS, which corresponded with a significant increase in zoospore formation and release. The decline in the percentage of metabolically active sporangia and increase in the number of zoospores fit both a linear and log regression model. The FUN-1 dye was suitable for distinguishing between live and dead sporangia and effective in monitoring the change in metabolic activity of sporangia over time. It will be useful in determining parameters, including P. capsici culture age, that maximize production of zoospores in vitro.

Genetic investigation of the nonhost resistance of wild lettuce, Lactuca saligna, to lettuce downy mildew, Bremia lactucae

NARCIS (Netherlands)

Boer, den E.

2014-01-01

Abstract

Downy mildew (Bremia lactucae) in lettuce (Lactuca sativa) is a devastating foliar disease causing high losses in lettuce cultivation. The wild lettuce and nonhost species, Lactuca saligna, is absolute resistant to downy mildew and

Assessment and Characterisation of Ireland's Green Tides (Ulva Species).

Science.gov (United States)

Wan, Alex H L; Wilkes, Robert J; Heesch, Svenja; Bermejo, Ricardo; Johnson, Mark P; Morrison, Liam

2017-01-01

Enrichment of nutrients and metals in seawater associated with anthropogenic activities can threaten aquatic ecosystems. Consequently, nutrient and metal concentrations are parameters used to define water quality. The European Union's Water Framework Directive (WFD) goes further than a contaminant-based approach and utilises indices to assess the Ecological Status (ES) of transitional water bodies (e.g. estuaries and lagoons). One assessment is based upon the abundance of opportunistic Ulva species, as an indication of eutrophication. The objective of this study was to characterise Ireland's Ulva blooms through the use of WFD assessment, metal concentrations and taxonomic identity. Furthermore, the study assessed whether the ecological assessment is related to the metal composition in the Ulva. WFD algal bloom assessment revealed that the largest surveyed blooms had an estimated biomass of 2164 metric tonnes (w/w). DNA sequences identified biomass from all locations as Ulva rigida, with the exception of New Quay, which was Ulva rotundata. Some blooms contained significant amounts of As, Cu, Cr, Pb and Sn. The results showed that all metal concentrations had a negative relationship (except Se) with the Ecological Quality Ratio (EQR). However, only in the case of Mn were these differences significant (p = 0.038). Overall, the metal composition and concentrations found in Ulva were site dependent, and not clearly related to the ES. Nevertheless, sites with a moderate or poor ES had a higher variability in the metals levels than in estuaries with a high ES.

Assessment and Characterisation of Ireland's Green Tides (Ulva Species)

Science.gov (United States)

Wilkes, Robert J.; Heesch, Svenja; Bermejo, Ricardo; Johnson, Mark P.; Morrison, Liam

2017-01-01

Enrichment of nutrients and metals in seawater associated with anthropogenic activities can threaten aquatic ecosystems. Consequently, nutrient and metal concentrations are parameters used to define water quality. The European Union’s Water Framework Directive (WFD) goes further than a contaminant-based approach and utilises indices to assess the Ecological Status (ES) of transitional water bodies (e.g. estuaries and lagoons). One assessment is based upon the abundance of opportunistic Ulva species, as an indication of eutrophication. The objective of this study was to characterise Ireland’s Ulva blooms through the use of WFD assessment, metal concentrations and taxonomic identity. Furthermore, the study assessed whether the ecological assessment is related to the metal composition in the Ulva. WFD algal bloom assessment revealed that the largest surveyed blooms had an estimated biomass of 2164 metric tonnes (w/w). DNA sequences identified biomass from all locations as Ulva rigida, with the exception of New Quay, which was Ulva rotundata. Some blooms contained significant amounts of As, Cu, Cr, Pb and Sn. The results showed that all metal concentrations had a negative relationship (except Se) with the Ecological Quality Ratio (EQR). However, only in the case of Mn were these differences significant (p = 0.038). Overall, the metal composition and concentrations found in Ulva were site dependent, and not clearly related to the ES. Nevertheless, sites with a moderate or poor ES had a higher variability in the metals levels than in estuaries with a high ES. PMID:28045947

The Influenced of Lactobacillus plantarum Starter Addition and The Length Time of Fermentation Process on The Activity of Seaweed Antioxidant Ulva lactuca from Krakal Beach, Yogyakarta

Science.gov (United States)

Ambarsari, N. D.; Rushanti, I. R. P. A.; Setyaji, A.; Ningsih, T. R.; Nurhana, N.; Subekhi, I.; Dewi, E. N.

2018-02-01

Seaweed contains phenol compound functioning as antioxidant. Lactobacillus plantarum starter addition in a fermentation process was expected will increase the activity of antioxidant. The purpose of this research was to determine the influence of L. plantarum addition and the length of fermentation on the activity of antioxidant in U. lactuca. The experiment was conducted with factorial design. The first treatment consisted 2 different factors namely without L. plantarum addition and L. plantarum addition. While the second treatment were the different length fermentation time: 0, 12, 24, and 36 hours. Each treatment were done in thriplicate. The data was analyzed using ANOVA and BNJ test was applied if there any differences betweenthe treatments. The results showed that the fresh U. lactuca with L. plantarum addition for 36 hours fermentation had TPC BAL 9,83 CFU/ml, pH 4,26, phenol 231 ppm and antioxidant activity IC501375,12 ppm. Dried U. lactuca with L. plantarum addition that was fermentized for 36 hours had TPC BAL 9,10 CFU/ml, pH 4,75, phenol 166,24 ppm and antioxidant activity IC504070,32 ppm. The fresh U. lactuca with L. plantarum addition for 36 hours fermentation was the best treatment since the antioxidant activity is IC501375,12 ppm. Although the antioxidant activity was categorized as weak but it was still showed an increase compared to the result of antioxidant activity with maceration method using n-hexana dissolver which was 11213,76 ppm, ethyl acetate 9770,285 ppm, and ethanol extact 4921,79 ppm.

Antimicrobial activity of Ulva reticulata and its endophytes

Science.gov (United States)

Dhanya, K. I.; Swati, V. I.; Vanka, Kanth Swaroop; Osborne, W. J.

2016-04-01

Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of prospective metabolites from seaweed and its endophytes, thereby exploiting the properties in resisting bacterial diseases. The current study was aimed to assess the antimicrobial activity of extracts obtained from Ulva reticulate, for which metabolites of Ulva reticulata and its endophytes were extracted and assessed against human pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Bacillus subtilis. It was observed that the hexane extract of isolate VITDSJ2 was effective against all the tested pathogens but a significant inhibition was observed for Staphylococcus aureus and Escherichia coli. Further, Gas chromatography coupled with Mass spectroscopy (GC-MS) revealed the existence of phenol, 3, 5-bis (1, 1-dimethylethyl) in the crude hexane extract which is well-known to possess antibacterial activity. The effective isolate VITDSJ2 was identified to be the closest neighbour of Pseudomonas stutzeri by phenotypic and genotypic methods. The crude extracts of the seaweed Ulva reticulata was also screened for antibacterial activity and the hexane extract was effective in showing inhibition against all the tested pathogens. The compound in the crude extract of Ulva reticulata was identified as hentriacontane using GC-MS. The extracts obtained from dichloromethane did not show significant activity in comparison with the hexane extracts. Hence the metabolites of Ulva reticulata and the bacterial secondary metabolites of the endophytes could be used in the treatment of bacterial infections.

A Myb transcription factor of Phytophthora sojae, regulated by MAP kinase PsSAK1, is required for zoospore development.

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Meng Zhang

Full Text Available PsSAK1, a mitogen-activated protein (MAP kinase from Phytophthora sojae, plays an important role in host infection and zoospore viability. However, the downstream mechanism of PsSAK1 remains unclear. In this study, the 3'-tag digital gene expression (DGE profiling method was applied to sequence the global transcriptional sequence of PsSAK1-silenced mutants during the cysts stage and 1.5 h after inoculation onto susceptible soybean leaf tissues. Compared with the gene expression levels of the recipient P. sojae strain, several candidates of Myb family were differentially expressed (up or down in response to the loss of PsSAK1, including of a R2R3-type Myb transcription factor, PsMYB1. qRT-PCR indicated that the transcriptional level of PsMYB1 decreased due to PsSAK1 silencing. The transcriptional level of PsMYB1 increased during sporulating hyphae, in germinated cysts, and early infection. Silencing of PsMYB1 results in three phenotypes: a no cleavage of the cytoplasm into uninucleate zoospores or release of normal zoospores, b direct germination of sporangia, and c afunction in zoospore-mediated plant infection. Our data indicate that the PsMYB1 transcription factor functions downstream of MAP kinase PsSAK1 and is required for zoospore development of P. sojae.

Removal of heavy metals from aqueous solution by nonliving Ulva seaweed as biosorbent.

Science.gov (United States)

Suzuki, Yoshihiro; Kametani, Takuji; Maruyama, Toshiroh

2005-05-01

The growth of dense green seaweed mats of Ulva spp. is an increasing problem in estuaries and coasts worldwide. The enormous amount of Ulva biomass thus becomes a troublesome waste disposal problem. On the other hand, it has been revealed that nonliving seaweed biomass, particularly brown seaweeds, has a high capacity for assimilating heavy metals. In this study, the possibility of using Ulva seaweed biomass as a biosorbent for the removal of heavy metals was examined. After processing, the biomass material was very easy to separate from the aqueous solution using a mesh. The sorption capacity of Cd on Ulva biomass increased upon pretreatment with alkali solution. The outstanding function of the biosorbent was demonstrated at around pH 8. On the basis of the Langmuir isotherms of Cd, Zn and Cu using the alkali-pretreated biomass, the parameters q(m) and b were determined to be within the narrow range of 60-90 mg/g and 0.03-0.04 L/mg, respectively, for each metal. Given the q(m) and b values, Ulva seaweed is a good biosorbent material for removing heavy metals. In an experiment using artificial wastewater containing Cd, Zn, Cu, Cr and Ni, it was possible to remove each metal simultaneously using Ulva biomass. Adsorption by Ulva biomass is effective for the removal of heavy metals from wastewater.

Effects of sewage contamination on macro-algae and shellfish at Moa Point, New Zealand, using stable carbon and nitrogen isotopes

International Nuclear Information System (INIS)

Rogers, K.M.

1999-01-01

Stable carbon and nitrogen isotopes have been used to characterise sewage discharge and effects on seaweed (Ulva lactuca L.), blue mussels (Mytilus galloprovincialis), and limpets (Cellana denticulata) from Moa Point Bay, New Zealand. The nitrogen ( 15 N / 14 N) ratio is shown to be a good tracer of sewage pollution in Ulva lactuca and associated grazers (Cellana denticulata) as a result of the increased contribution of urea and ammonia to the surrounding marine environment from the sewage outfall. The carbon ( 13 C / 12 C) ratio is suggested as a more appropriate sewer tracer for mussels (Mytilus galloprovincialis), which filter feed the particulate organic matter from the effluent. Lower carbon : nitrogen ratios were found in U. lactuca sampled from the outfall region, compared to uncontaminated control sites, however carbon : nitrogen ratios do not vary significantly amongst shellfish species. (author). 18 refs., 4 figs., 2 tabs

Morphological and ultrastructural studies on Ulva flexuosa subsp. pilifera (Chlorophyta from Poland

Directory of Open Access Journals (Sweden)

Beata Messyasz

2013-06-01

Full Text Available Ulva flexuosa subsp. pilifera (Kütz. M. J. Wynne 2005 (= Enteromorpha pilifera Kützing 1845 was previously found in Argentina, the Czech Republic, Germany, Hungary, Romania, Slovakia and Sweden, recently also in Poland. The genus Ulva was first time described as Enteromorpha. Interestingly, Enteromorpha is used nowadays as a synonym for Ulva, a development which is based on molecular data. The morphologies of both young and mature specimens were studied, and most life cycle stages could be observed. Further, the formation of calcium carbonate crystals on the surface of Ulva thalli seems to influence the arrangement of the cells. A detailed ultrastructural (TEM analysis of cell walls is presented. The TEM reveals in great details highly complex, irregular structures with stratification lines.

Multimodal sensorimotor system in unicellular zoospores of a fungus.

Science.gov (United States)

Swafford, Andrew J M; Oakley, Todd H

2018-01-19

Complex sensory systems often underlie critical behaviors, including avoiding predators and locating prey, mates and shelter. Multisensory systems that control motor behavior even appear in unicellular eukaryotes, such as Chlamydomonas , which are important laboratory models for sensory biology. However, we know of no unicellular opisthokonts that control motor behavior using a multimodal sensory system. Therefore, existing single-celled models for multimodal sensorimotor integration are very distantly related to animals. Here, we describe a multisensory system that controls the motor function of unicellular fungal zoospores. We found that zoospores of Allomyces arbusculus exhibit both phototaxis and chemotaxis. Furthermore, we report that closely related Allomyces species respond to either the chemical or the light stimuli presented in this study, not both, and likely do not share this multisensory system. This diversity of sensory systems within Allomyces provides a rare example of a comparative framework that can be used to examine the evolution of sensory systems following the gain/loss of available sensory modalities. The tractability of Allomyces and related fungi as laboratory organisms will facilitate detailed mechanistic investigations into the genetic underpinnings of novel photosensory systems, and how multisensory systems may have functioned in early opisthokonts before multicellularity allowed for the evolution of specialized cell types. © 2018. Published by The Company of Biologists Ltd.

Efficacy of marine green alga Ulva fasciata extract on the management of shrimp bacterial diseases Eficacia del extracto del alga marina verde Ulva fasciata sobre el manejo de las enfermedades bacterianas en camarones

Directory of Open Access Journals (Sweden)

Joseph Selvin

2011-07-01

Full Text Available Secondary metabolites of the green algae, Ulva fasciata, were tested to determine the efficacy of controlling shrimp bacterial pathogens. Exploratory experiments indicated that an intermediate dose (1 g kg-1 of shrimp of Ulva in the diet was highly effective at controlling bacterial pathogens of shrimp, as compared to lower (500 mg kg-1 and higher (1.5 g kg-1 doses. The pilot experiments evaluated the percent of relative protection afforded shrimps treated with Ulva diet and faced with various concentrations of bacterial pathogen. The survival of shrimps treated with Ulva diet was significant (P Metabolites secundario de algas verdes Ulva fasciata fue probado para determinar la eficacia de controlar el camarón pathogens bacterial. Las conclusiones de experimentos exploratorios indicaron que la dosis mediana (1 g kg-1 de camarón de dieta Ulva era sumamente eficaz en el control de pathogens bacterial de camarón cuando comparado al más abajo (500 mg kg-1 y más alto (1,5 g kg-1 dosis. En los experimentos pilotos, la protección de pariente de por ciento de camarones trató con la dieta Ulva y desafió con varias concentraciones de bacterial patógeno fueron evaluados. La supervivencia de camarones trató con la dieta Ulva era significativo (P < 0,01. Basado en las conclusiones presentes, podría ser deducido que U. verde fasciata puede ser una fuente excelente para desarrollar la comida potente medicinal para la dirección de enfermedad de camarón.

Origin and domestication of Lactuca sativa L.

NARCIS (Netherlands)

Vries, de I.M.

1997-01-01

The domestication of lettuce, Lactuca sativa L. is described on the basis of literature study. The centre of origin is discussed. A historical survey is made of the distribution of the groups of Lactuca cultivars over the world.

Biochemical studies in Ulva reticulata Forsskal

Digital Repository Service at National Institute of Oceanography (India)

Dhargalkar, V.K.

Major metabolites like proteins, carbohydrates and lipids in the alga Ulva reticulata were estimated. Carbohydrate was found to decrease after December which may perhaps be due to the spore formation and extensive growth of the thallus. Protein...

The green seaweed Ulva: A model system to study morphogenesis

OpenAIRE

Thomas eWichard; Benedicte eCharrier; Benedicte eCharrier; Frédéric eMineur; John Henry Bothwell; Olivier eDe Clerck; Juliet C. Coates

2015-01-01

Green macroalgae, mostly represented by the Ulvophyceae, the main multicellular branch of the Chlorophyceae, constitute important primary producers of marine and brackish coastal ecosystems. Ulva or sea lettuce species are some of the most abundant representatives, being ubiquitous in coastal benthic communities around the world. Nonetheless the genus also remains largely understudied. This review highlights Ulva as an exciting novel model organism for studies of algal growth, development and...

The green seaweed Ulva: a model system to study morphogenesis

OpenAIRE

Wichard, Thomas; Charrier, Bénédicte; Mineur, Frédéric; Bothwell, John H; De Clerck, Olivier; Coates, Juliet C

2015-01-01

International audience; Green macroalgae, mostly represented by the Ulvophyceae, the main multicellular branch of the Chlorophyceae, constitute important primary producers of marine and brackish coastal ecosystems. Ulva or sea lettuce species are some of the most abundant representatives, being ubiquitous in coastal benthic communities around the world. Nonetheless the genus also remains largely understudied. This review highlights Ulva as an exciting novel model organism for studies of algal...

Composition, nutritional aspects and effect on serum parameters of marine algae Ulva rigida.

Science.gov (United States)

Taboada, Cristina; Millán, Rosendo; Míguez, Isabel

2010-02-01

Algae are commonly consumed in Asia and have also gained popularity in Europe. However, data on the bioavailability of their components are limited. The present study was designed to determine the composition of Ulva rigida and the effects of inclusion of 10% of the algae in a standard diet for 4 weeks on nutritive value and serum parameters in order to consider the usefulness of Ulva as a dietary supplement. Ulva rigida is rich in protein, carbohydrates, fibre, vitamins and minerals and has a low lipid content. Analysis of the amino acid composition revealed good-quality protein. The algae were well accepted by experimental animals and did not significantly change nutritional parameters but reduced LDL cholesterol. Ulva rigida is an excellent source of nutrients and could improve a balanced diet. Further studies are required to research the potential of the seaweed as a natural source of bioactive compounds.

Changes in N cycling induced by Ulva detritus enrichment of sediments

DEFF Research Database (Denmark)

Garcia-Robledo, Emilio; Revsbech, Niels Peter; Risgaard-Petersen, Nils

2013-01-01

Macroalgal accumulation and decomposition in shallow water environments typically result in an increase in the organic matter content of the sediment, affecting both benthic metabolism and nutrient dynamics. The present study investigates how a pulse addition of Ulva detritus to estuarine sediment...... of oxygen and nitrate. Nitrification increased significantly in response to enhanced NH4 + supply from decomposition of the Ulva detritus. Aerobic ammonia oxidation exceeded rates of nitrite oxidation, leading to accumulation of NO2 − in the oxic zone of the sediment. Nitrite and NO3 − produced via...... nitrification diffused up to the sediment surface, inducing a net efflux to the water column, and downwards, supporting a high rate of denitrification coupled to nitrification. The present study shows that organic enrichment with Ulva detritus enhances sediment oxygen uptake, nitrification and denitrification...

Marine macrophytes of Minicoy (Lakshadweep) coral atoll of the Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Untawale, A.G.; Jagtap, T.G.

Thirty-seven species of marine algae, belonging to 31 genera 5 seagrass species and one mangrove species, were recorded from Minicoy Atoll. The predominant seaweeds observed were Enteromorpha clathrata, Caulerpa species, Ulva lactuca, Halimeda...

Methods for the induction of reproduction in a tropical species of filamentous ulva.

Directory of Open Access Journals (Sweden)

Christina Carl

Full Text Available The green seaweed Ulva is a major fouling organism but also an edible aquaculture product in Asia. This study quantified for the first time the effect of key factors on the reproduction of a tropical species of filamentous Ulva (Ulva sp. 3. The controlled timing of release of swarmers (motile reproductive bodies was achieved when experiments were initiated in the early afternoon by exposing the thalli to a temperature shock (4°C for 10 min and subsequently placing them into autoclaved filtered seawater under a 12 h light: 12 h dark photoperiod at 25°C. The release of swarmers then peaked two days after initiation. In contrast, segmentation, dehydration, salinity or time of initiation of experiments had no effect of any magnitude on reproduction. The released swarmers were predominantly biflagellate (95%, negatively phototactic and germinated without complementary gametes. This indicates that Ulva sp. 3 has a simple asexual life history dominated by biflagellate zoids.

Methods for the induction of reproduction in a tropical species of filamentous ulva.

Science.gov (United States)

Carl, Christina; de Nys, Rocky; Lawton, Rebecca J; Paul, Nicholas A

2014-01-01

The green seaweed Ulva is a major fouling organism but also an edible aquaculture product in Asia. This study quantified for the first time the effect of key factors on the reproduction of a tropical species of filamentous Ulva (Ulva sp. 3). The controlled timing of release of swarmers (motile reproductive bodies) was achieved when experiments were initiated in the early afternoon by exposing the thalli to a temperature shock (4°C) for 10 min and subsequently placing them into autoclaved filtered seawater under a 12 h light: 12 h dark photoperiod at 25°C. The release of swarmers then peaked two days after initiation. In contrast, segmentation, dehydration, salinity or time of initiation of experiments had no effect of any magnitude on reproduction. The released swarmers were predominantly biflagellate (95%), negatively phototactic and germinated without complementary gametes. This indicates that Ulva sp. 3 has a simple asexual life history dominated by biflagellate zoids.

Genetic diversity and evolution in Lactuca L. (Asteraceae)

NARCIS (Netherlands)

Wei, Z.

2016-01-01

Cultivated lettuce (Lactuca sativa L.) is an important leafy vegetable worldwide. However, the phylogenetic relationships between domesticated lettuce and its wild relatives are still not clear. In this thesis, I focus on the phylogenetic relationships within Lactuca L.,

Effect of graded levels of dietary seaweed (Ulva sp.) on growth, hematological and serum biochemical parameters in dusky kob, Argyrosomus japonicus, sciaenidae

OpenAIRE

Molatelo Junior Madibana; Victor Mlambo; Brett Lewis; Chris Fouché

2017-01-01

This study was designed to assess the effect of incorporating graded levels of green macroalgae seaweed (Ulva sp.) into diets of juvenile dusky kob (Argyrosomus japonicus) on growth performance, hematology and serum biochemistry. Five experimental diets were formulated to contain 0 (Ulva0), 50 (Ulva50), 100 (Ulva100), 150 (Ulva150) and 200 (Ulva200) g seaweed meal/kg commercial kob feed on a dry matter basis. Seventy-seven dusky kob fingerlings (mean body mass 9.14â¯Â±â¯0.30â¯g) were distribu...

Effect of graded levels of dietary seaweed (Ulva sp. on growth, hematological and serum biochemical parameters in dusky kob, Argyrosomus japonicus, sciaenidae

Directory of Open Access Journals (Sweden)

Molatelo Junior Madibana

2017-09-01

Full Text Available This study was designed to assess the effect of incorporating graded levels of green macroalgae seaweed (Ulva sp. into diets of juvenile dusky kob (Argyrosomus japonicus on growth performance, hematology and serum biochemistry. Five experimental diets were formulated to contain 0 (Ulva0, 50 (Ulva50, 100 (Ulva100, 150 (Ulva150 and 200 (Ulva200 g seaweed meal/kg commercial kob feed on a dry matter basis. Seventy-seven dusky kob fingerlings (mean body mass 9.14 ± 0.30 g were distributed into each of 20 experimental tanks and offered diets at 2.8% body mass. Weight and length of fish were measured weekly for 9 weeks. At the end of the feeding trial, fish fed Ulva50 had higher body mass (38.20 ± 1.38 g compared to those fed the other three Ulva-based diets. Fish offered Ulva200 had significantly (P  .05 by dietary treatments. However, the levels of both blood cholesterol and alkaline phosphatase tended to decrease as dietary Ulva inclusion levels increased. These results indicate that Ulva could be incorporated at the rate of 50 g kg−1 in future commercial dusky kob diets without any negative effects on feed utilizationa and growth performance. Hematology and serum biochemistry results indicate that dietary inclusion of Ulva had no adverse effects on physiological status of the fish. Keywords: Ulva sp., Haematology, Dusky kob, Feed conversion efficiency, Specific growth rate

Implications of Zostera noltii recolonization on Hydrobia ulvae population structure success.

Science.gov (United States)

Grilo, T F; Cardoso, P G; Pardal, M A

2012-02-01

Over 1990-1998, the Mondego estuary, Portugal, experienced profound modifications due to eutrophication, culminating in the disappearance and replacement of Zostera noltii by opportunistic macroalgae in the inner most disturbed areas. A decade after restoration measures implementation, Z. noltii started to gradually recolonize the inner parts, following 20 years of absence. This work explores the factors underlying successful Z. noltii recolonization and its subsequent implications on a mud snail Hydrobia ulvae population. During the macroalgal bloom, highest values in H. ulvae abundance, biomass and production were recorded, strongly declining afterwards. Three recovery attempts characterized the post-restoration phase, with considerably increases in H. ulvae abundance, biomass and production since Z. noltii reappearance. The seagrass provided long-term protection and abundant food resources for reproductive adults, contrarily to the ephemeral macroalgae. Through time, large size individuals increased, becoming the population more stable, structured and similar to the one inhabiting the "original"Z. noltii meadows. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cultivation and conversion of marine macroalgae. [Gracilaria and Ulva

Energy Technology Data Exchange (ETDEWEB)

Ryther, J.H.; DeBusk, T.A.; Blakeslee, M.

1984-05-01

Research was conducted on the development of an alternative ocean energy farm concept that would not be dependent upon deep ocean water or other extraneous sources for its nutrient supply and that could be located in shallow, near shore, and protected coastal ocean areas. There are five tasks reported in this document: determination of the annual yield of Ulva in non-intensive cultures; evaluation of the effect of carbon concentration on Gracilaria and Ulva yields; evaluation of spray/mist culture of Ulva and Gracilaria; species screening for the production of petroleum replacement products; and synthesis analysis, and economic energy evaluation of culture data. An alternative concept to open ocean culture is a land-based energy production system utilizing saline waters from underground aquifers or enclosed coastal areas. Research was performed to evaluate growth and biomass production of all macroscopic algal species that could be obtained in adequate quantity in the central Florida area. A total of 42 species were grown in specially adapted burial vaults. These included 16 green algae (Garcilaria 4 weekshlorophyta), 2 brown algae (Phaeophyta), and 18 red algae (Rhodophyta). Of these, the most successful and suitable species were a strain of Gracilaria (a red seaweed) and Ulva (a green seaweed). These two species have a high carbohydrate content that may be anaerobically digested to methane gas. Well-nourished Gracilaria will double its biomass in 1 to 4 weeks, depending on the season, water flow, and other variables. After its biomass has doubled (i.e., from 2 to 4 kg/m/sup 2/) the incremental growth is harvested to return the crop to a starting density. Enrichment of the new starting crop following harvest could conceivably be accomplished onsite at the seaweed farm, but the rapid uptake and storage of nutrients by depleted seaweeds makes possible a simpler process, known as pulse fertilization.

Stability of Cucumber Necrosis Virus at the Quasi-6-Fold Axis Affects Zoospore Transmission.

Science.gov (United States)

Sherman, Michael B; Kakani, Kishore; Rochon, D'Ann; Jiang, Wen; Voss, Neil R; Smith, Thomas J

2017-10-01

Cucumber necrosis virus (CNV) is a member of the genus Tombusvirus and has a monopartite positive-sense RNA genome. CNV is transmitted in nature via zoospores of the fungus Olpidium bornovanus As with other members of the Tombusvirus genus, the CNV capsid swells when exposed to alkaline pH and EDTA. We previously demonstrated that a P73G mutation blocks the virus from zoospore transmission while not significantly affecting replication in plants (K. Kakani, R. Reade, and D. Rochon, J Mol Biol 338:507-517, 2004, https://doi.org/10.1016/j.jmb.2004.03.008). P73 lies immediately adjacent to a putative zinc binding site (M. Li et al., J Virol 87:12166-12175, 2013, https://doi.org/10.1128/JVI.01965-13) that is formed by three icosahedrally related His residues in the N termini of the C subunit at the quasi-6-fold axes. To better understand how this buried residue might affect vector transmission, we determined the cryo-electron microscopy structure of wild-type CNV in the native and swollen state and of the transmission-defective mutant, P73G, under native conditions. With the wild-type CNV, the swollen structure demonstrated the expected expansion of the capsid. However, the zinc binding region at the quasi-6-fold at the β-annulus axes remained intact. By comparison, the zinc binding region of the P73G mutant, even under native conditions, was markedly disordered, suggesting that the β-annulus had been disrupted and that this could destabilize the capsid. This was confirmed with pH and urea denaturation experiments in conjunction with electron microscopy analysis. We suggest that the P73G mutation affects the zinc binding and/or the β-annulus, making it more fragile under neutral/basic pH conditions. This, in turn, may affect zoospore transmission. IMPORTANCE Cucumber necrosis virus (CNV), a member of the genus Tombusvirus , is transmitted in nature via zoospores of the fungus Olpidium bornovanus While a number of plant viruses are transmitted via insect vectors

Effect of temperature, salinity and biofilm on the zoospores settlement of Enteromorpha flexuosa (Wulfen) J.Agardh

Digital Repository Service at National Institute of Oceanography (India)

Imchen, T.

by permanent adhesion through rapid secretion and curing of an N-linked, self-aggregating glycoprotein that anchors the spore to the substratum surface4. A variety of factors influence settlement of zoospores (biological4; topography of surface5-6; charge...

The fast expansion of Pyropia aquaculture in ;Sansha; regions should be mainly responsible for the Ulva blooms in Yellow Sea

Science.gov (United States)

Zhang, Jianheng; Zhao, Peng; Huo, Yuanzi; Yu, Kefeng; He, Peimin

2017-04-01

Massive Ulva blooms became an environmental disaster in the Yellow Sea from 2007 to 2015. In this study, field shipboard observations indicated that Ulva blooms originated in Pyropia aquaculture area, and the morphology of initial floating Ulva seaweed have the structure of rhizoid, which is similar with the attached Ulva on the Pyropia rafts. The spatial distribution of Ulva microscopic propagules in the southern Yellow Sea also supported that the blooms originated in the Pyropia aquaculture area. Besides, numerical model was used in this study, showing the origin of macroalgal blooms was traced to "Sansha" regions which accounted for almost 70% of the total Pyropia aquaculture area. We conclude that the significant biomass (4252 tons) of Ulva species on the Pyropia rafts during the harvesting season in "Sansha" regions played an important role in the early rapid development of blooms in the Yellow Sea.

Stable isotope variations in benthic primary producers along the Bosphorus (Turkey): A preliminary study

International Nuclear Information System (INIS)

Calizza, Edoardo; Aktan, Yelda; Costantini, Maria Letizia; Rossi, Loreto

2015-01-01

Highlights: • Nitrogen pollution along the Bosphorus Strait was investigated. • C and N isotopic and elemental analyses on benthic primary producers were performed. • δ 15 N decreased, while δ 13 C and N% increased from north to south along the Strait. • Ulva lactuca was more useful than epiphytes as indicator of nitrogen pollution. • Preliminary isotopic analyses on resident organisms are useful monitoring tools. - Abstract: The Bosphorus Strait is a dynamic and complex system. Recent evidences showed nitrogen and heavy metal concentrations to follow opposite patterns across the Strait, suggesting a complex spatial organisation of the anthropogenic disturbance in this system. Here, we provide isotopic information on the origin and transportation of dissolved nitrogen along the Bosphorus. C and N isotopic and elemental analyses were performed on specimens of Ulva lactuca and associated epiphytes sampled in five locations across the Strait. Variations in C and N isotopic signatures were observed in U. lactuca, pointing to a decrease in the availability of anthropogenic organic dissolved nitrogen along a north-south direction. Conversely, epiphytes did not show isotopic or elemental patterns across the Strait. These results suggest that preliminary stable isotope surveys in extended costal systems basing on U. lactuca can represent a valuable tool to focus meaningful targets and hypotheses for pollution studies in the Mediterranean region

UJI AKTIVITAS ANTIBAKTERI EKSTRAK KASAR LIPID Ulva fasciata TERHADAP Bacillus cereus

Directory of Open Access Journals (Sweden)

Riong Seulina Panjaitan

2017-01-01

Full Text Available Abstract: The increasing of antimicrobial resistance in medical field has become a serious problem which is have to be solved by exploring raw material on natural product. Seaweed or macroalgae is one of marine natural wealth of Indonesia’s sea. In this research, lipid extraction of seaweed (macroalgae Ulva fasciata has been done according to Folch method by using sochlet and mixure of solvent namely chloroform:methanol (2:1/ (v/v. The result gave two phase namely chloroform phase (0,6% (v/b and methanol phase (7,79% (v/b. Furthermore, both of phase of crude extract lipid Ulva fasciata were tested their antibacterial activities against Bacillus cereus bacterial which is three times. Tetracyclin is used as positive control and the solvent (methanol-chloroform is used as negative control. The results were both of phase gave antibacterial activity namely 0,02 mm/ μg extract for chloroform phase and 0,02 mm/ μg extract for methanol phase.Abstrak: Peningkatan kasus resistensi antimikroba pada dunia medis telah menjadi masalah yang serius sehingga perlu dilakukan pengeksplorasian bahan baku untuk antibiotik khususnya dari bahan alam. Rumput laut (makroalga merupakan salah satu kekayaan alam hayati laut Indonesia yang memiliki kandungan lipid. Pada penelitian ini dilakukan ekstraksi lipid rumput laut (makroalga Ulva fasciata berdasarkan metode Folch dengan menggunakan sokhlet dan campuran pelarut yang digunakan yaitu kloroform:metanol (2:1/ (v/v. Hasil ekstraksi lipid Ulva fasciata menghasilkan dua fasa yaitu fasa kloroform sebanyak 0,6 % (v/b dan fasa metanol sebanyak 7,79 % (v/b. Selanjutnya kedua fasa ekstrak kasar lipid Ulva fasciata tersebut diuji aktivitas antibakterinya terhadap bakteri Bacillus cereus sebanyak tiga kali pengulangan. Kontrol positif yang digunakan adalah tetrasiklin dan kontrol negatifnya adalah pelarut yaitu kloroform dan metanol. Hasil penelitian menunjukkan bahwa kedua fasa tersebut memberikan aktivitas antibakteri

Studies of marine macroalgae: saline desert water cultivation and effects of environmental stress on proximate composition. Final subcontract report. [Gracilaria tikvahiae; Ulva lactuca

Energy Technology Data Exchange (ETDEWEB)

Ryther, J.H.; DeBusk, T.A.; Peterson, J.E.

1985-11-01

The results presented in this report address the growth potential of marine macroalgae cultivated in desert saline waters, and the effects of certain environmental stresses (e.g., nitrogen, salinity, and temperature) on the proximate composition of several marine macroalgae. Two major desert saline water types were assayed for their ability to support the growth of Gracilaria, Ulva, and Caulerpa. Both water types supported short term growth, but long term growth was not supported. Carbohydrate levels in Gracilaria were increased by cultivation under conditions of high salinity, low temperature, and low nitrogen and phosphorous availability. Data suggests that it may be possible to maximize production of useful proximate constituents by cultivating the algae under optimum conditions for growth, and then holding the resulting biomass under the environmental conditions which favor tissue accumulation of the desired storage products. 16 refs., 21 figs., 19 tabs.

Evidence for a race-specific resistance factor in some lettuce (Lactuca sativa L.) cultivars previously considered to be universally susceptible to Bremia lactucae regel.

Science.gov (United States)

Crute, I R; Lebeda, A

1981-05-01

Previously undetected race-specific resistance to Bremia lactucae (downy mildew) was located in many lettuce cultivars hitherto considered to be universally susceptible to this disease. This resistance factor(s) may also be widely distributed in other cultivars known to carry combinations of already recognised factors R1 to R11. Specific virulence to match this resistance is almost invariably present in pathogen collections. This situation may be either a relic of the evolutionary history of the B. lactucae - L. sativa asssociation or may reflect a rare mutation in B. lactucae for avirulence on all but a few specialised L. sativa genotypes.

Energetic consequences of a major change in habitat use: endangered Brent Geese Branta bernicla hrota losing their main food source

DEFF Research Database (Denmark)

Clausen, Kevin Kuhlmann; Clausen, Preben; Fælled, Casper Cæsar

2012-01-01

breeding population of Light-bellied Brent Geese Branta bernicla hrota has experienced substantial changes in habitat use at this traditional autumn staging area. Declines in seagrasses have caused birds to depend increasingly on Sea Lettuce Ulva lactuca in recent years, and forced birds into terrestrial...

Cardioprotective effect of melatonin-standardized ethanol extract of ...

African Journals Online (AJOL)

Results: ISO-treated group demonstrated a significant (p < 0.05) elevation in the level of ... Journal Citation Reports/Science Edition, Directory of Open Access Journals ... water, dried and were grinded to make powder. .... radicals and antioxidative defense system, .... Potentials of Seaweed Biomass Ulva lactuca and.

The effect of rumen ciliates on chitinolytic activity, chitin content and the number of fungal zoospores in the rumen fluid of sheep.

Science.gov (United States)

Miltko, Renata; Bełżecki, Grzegorz; Herman, Andrzej; Kowalik, Barbara; Skomiał, Jacek

2016-12-01

The objective of this study was to investigate the effect of selected protozoa on the degradation and concentration of chitin and the numbers of fungal zoospores in the rumen fluid of sheep. Three adult ewes were fed a hay-concentrate diet, defaunated, then monofaunated with Entodinium caudatum or Diploplastron affine alone and refaunated with natural rumen fauna. The average density of the protozoa population varied from 6.1 · 10(4) (D. affine) to 42.2 · 10(4) cells/ml rumen fluid (natural rumen fauna). The inoculation of protozoa in the rumen of defaunated sheep increased the total activity of chitinolytic enzymes from 2.9 to 3.6 μmol N-acetylglucosamine/g dry matter (DM) of rumen fluid per min, the chitin concentration from 6.3 to 7.2 mg/g DM of rumen fluid and the number of fungal zoospores from 8.1 to 10.9 · 10(5) cells/ml rumen fluid. All examined indices showed diurnal variations. Ciliate population density was highest immediately prior to feeding and lowest at 4 h thereafter. The opposite effects were observed for the numbers of fungal zoospores, the chitin concentration and chitinolytic activity. Furthermore, it was found that chitin from zoospores may account for up to 95% of total microbial chitin in the rumen fluid of sheep. In summary, the examined ciliate species showed the ability of chitin degradation as well as a positive influence on the development of the ruminal fungal population.

Photosynthetic response of two seaweed species along an urban pollution gradient: evidence of selection of pollution-tolerant species.

Science.gov (United States)

Scherner, F; Bonomi Barufi, J; Horta, P A

2012-11-01

Urbanization leads to the expansion of ephemeral seaweed species and the decline of important perennial, canopy-forming seaweed species. Understanding the mechanisms that lead to these changes is a current challenge. In the present study, laboratory assays and field transplantations were performed with two seaweed species: the perennial, canopy-forming seaweed Sargassum stenophyllum and the ephemeral seaweed Ulva lactuca. Photosynthetic efficiency was assessed using modulated chlorophyll fluorometry. Brief exposure to urban waters does not appear to be a major stressor to the photosynthetic efficiency of either species. However, after 26 days of transplantation in urban waters, S. stenophyllum declined, whereas U. lactuca had enhanced photosynthetic efficiency. This difference reflects their divergent abilities to regulate the energy distribution at the PSII and shows that urban stressors alter these mechanisms. Our results provide evidence of the physiological causes for the decline of Sargassum species and the expansion of Ulva species in impacted urban areas. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nutritional and Functional Bioactivity Value of Selected Azorean Macroalgae: Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea.

Science.gov (United States)

Paiva, Lisete; Lima, Elisabete; Neto, Ana Isabel; Marcone, Massimo; Baptista, José

2017-07-01

This study presents information on the biochemical composition (dry weight basis), nutritional aspects, and angiotensin I-converting enzyme (ACE) inhibitory properties of selected macroalgae (Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea) from Azores. Moisture content was very high (83.2% to 90.0% of fresh weight). Total dietary fiber (33.7% to 41.0%) that presented a good balance of both soluble and insoluble fibers (15.5% to 19.2% and 18.2% to 21.8%, respectively) was the most abundant component in these macroalgae. Protein and ash (ranged from 15.7% to 23.4% and 10.7% to 20.7%, respectively) were the 2nd most abundant components in red and green macroalgae, respectively. Moderate soluble carbohydrate contents (14.5% to 19.8%) were found in all species. Lipid contents were low (1.0% to 4.3%), particularly in Ulva species (1.0% to 1.7%), but contained higher unsaturated fatty acids (FAs) (7.5% to 32.9% and 29.6% to 69.2% of total FA for monounsaturated fatty acid and polyunsaturated fatty acid groups, respectively) than saturated fatty acid (23.3% to 46.8% of total FA) contents. All the macroalgal proteins had high digestibility in vitro (82.2% to 89.4%, relatively to sodium caseinate), contained high quantity of essential amino acids (45.3% to 58.1% of total amino acids), but in different proportions, and were rich in aspartic and glutamic acids that together account for 17.2% to 36.2% of the total amino acids. These results suggested that regular consumption of the selected macroalgae may improve human health and revealed that they can be used for producing food supplements for human and animal nutrition and/or pharmaceuticals with potential effect on the regional economy. Furthermore, the ACE-inhibitory IC 50 values of 0.095 to 0.695 mg/mL for the <1 kDa protein hydrolysate fraction revealed a potential impact on hypertension disorder. © 2017 Institute of Food Technologists®.

Phylogenetic relationships among Lactuca (Asteraceae) species and related genera based on ITS-1 DNA sequences.

Science.gov (United States)

Koopman, W J; Guetta, E; van de Wiel, C C; Vosman, B; van den Berg, R G

1998-11-01

Internal transcribed spacer (ITS-1) sequences from 97 accessions representing 23 species of Lactuca and related genera were determined and used to evaluate species relationships of Lactuca sensu lato (s.l.). The ITS-1 phylogenies, calculated using PAUP and PHYLIP, correspond better to the classification of Feráková than to other classifications evaluated, although the inclusion of sect. Lactuca subsect. Cyanicae is not supported. Therefore, exclusion of subsect. Cyanicae from Lactuca sensu Feráková is proposed. The amended genus contains the entire gene pool (sensu Harlan and De Wet) of cultivated lettuce (Lactuca sativa). The position of the species in the amended classification corresponds to their position in the lettuce gene pool. In the ITS-1 phylogenies, a clade with L. sativa, L. serriola, L. dregeana, L. altaica, and L. aculeata represents the primary gene pool. L. virosa and L. saligna, branching off closest to this clade, encompass the secondary gene pool. L. virosa is possibly of hybrid origin. The primary and secondary gene pool species are classified in sect. Lactuca subsect. Lactuca. The species L. quercina, L. viminea, L. sibirica, and L. tatarica, branching off next, represent the tertiary gene pool. They are classified in Lactuca sect. Lactucopsis, sect. Phaenixopus, and sect. Mulgedium, respectively. L. perennis and L. tenerrima, classified in sect. Lactuca subsect. Cyanicae, form clades with species from related genera and are not part of the lettuce gene pool.

An efficient method for zoospore production, infection and real-time quantification of Phytophthora cajani causing Phytophthora blight disease in pigeonpea under elevated atmospheric CO₂.

Science.gov (United States)

Sharma, Mamta; Ghosh, Raju; Tarafdar, Avijit; Telangre, Rameshwar

2015-03-25

Phytophthora blight caused by Phytophthora cajani is an emerging disease of pigeonpea (Cajanus cajan L.) affecting the crop irrespective of cropping system, cultivar grown and soil types. Current detection and identification methods for Phytophthora species rely primarily on cultural and morphological characteristics, the assessment of which is time-consuming and not always suitable. Sensitive and reliable methods for isolation, identification, zoospore production and estimating infection severity are therefore desirable in case of Phytophthora blight of pigeonpea. In this study, protocols for isolation and identification of Phytophthora blight of pigeonpea were standardized. Also the method for zoospore production and in planta infection of P. cajani was developed. Quantification of fungal colonization by P. cajani using real-time PCR was further standardized. Phytophthora species infecting pigeonpea was identified based on mycological characters such as growth pattern, mycelium structure and sporangial morphology of the isolates and confirmed through molecular characterization (sequence deposited in GenBank). For Phytophthora disease development, zoospore suspension of 1 × 10(5) zoospores per ml was found optimum. Phytophthora specific real-time PCR assay was developed using specific primers based on internal transcribed spacer (ITS) 1 and 2. Use of real-time PCR allowed the quantitative estimation of fungal biomass in plant tissues. Detection sensitivities were within the range of 0.001 pg fungal DNA. A study to see the effect of elevated CO₂ on Phytophthora blight incidence was also conducted which indicated no significant difference in disease incidence, but incubation period delayed under elevated CO₂ as compared to ambient level. The zoospore infection method for Phytophthora blight of pigeonpea will facilitate the small and large scale inoculation experiments and thus devise a platform for rapid and reliable screening against Phytophthora blight

African Journal of Aquatic Science - Vol 34, No 2 (2009)

African Journals Online (AJOL)

... of tissue nitrogen in cultivated Gracilaria gracilis (Rhodophyta) and Ulva lactuca (Chlorophyta) · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. DV Robertson-Andersson, DT Wilson, JJ Bolton, RJ Anderson, GW Maneveldt. http://dx.doi.org/10.2989/AJAS.2009.34.2.7.894 ...

Thermochemical hydrolysis of macroalgae Ulva for biorefinery: Taguchi robust design method

Science.gov (United States)

Jiang, Rui; Linzon, Yoav; Vitkin, Edward; Yakhini, Zohar; Chudnovsky, Alexandra; Golberg, Alexander

2016-06-01

Understanding the impact of all process parameters on the efficiency of biomass hydrolysis and on the final yield of products is critical to biorefinery design. Using Taguchi orthogonal arrays experimental design and Partial Least Square Regression, we investigated the impact of change and the comparative significance of thermochemical process temperature, treatment time, %Acid and %Solid load on carbohydrates release from green macroalgae from Ulva genus, a promising biorefinery feedstock. The average density of hydrolysate was determined using a new microelectromechanical optical resonator mass sensor. In addition, using Flux Balance Analysis techniques, we compared the potential fermentation yields of these hydrolysate products using metabolic models of Escherichia coli, Saccharomyces cerevisiae wild type, Saccharomyces cerevisiae RN1016 with xylose isomerase and Clostridium acetobutylicum. We found that %Acid plays the most significant role and treatment time the least significant role in affecting the monosaccharaides released from Ulva biomass. We also found that within the tested range of parameters, hydrolysis with 121 °C, 30 min 2% Acid, 15% Solids could lead to the highest yields of conversion: 54.134-57.500 gr ethanol kg-1 Ulva dry weight by S. cerevisiae RN1016 with xylose isomerase. Our results support optimized marine algae utilization process design and will enable smart energy harvesting by thermochemical hydrolysis.

Thermochemical hydrolysis of macroalgae Ulva for biorefinery: Taguchi robust design method.

Science.gov (United States)

Jiang, Rui; Linzon, Yoav; Vitkin, Edward; Yakhini, Zohar; Chudnovsky, Alexandra; Golberg, Alexander

2016-06-13

Understanding the impact of all process parameters on the efficiency of biomass hydrolysis and on the final yield of products is critical to biorefinery design. Using Taguchi orthogonal arrays experimental design and Partial Least Square Regression, we investigated the impact of change and the comparative significance of thermochemical process temperature, treatment time, %Acid and %Solid load on carbohydrates release from green macroalgae from Ulva genus, a promising biorefinery feedstock. The average density of hydrolysate was determined using a new microelectromechanical optical resonator mass sensor. In addition, using Flux Balance Analysis techniques, we compared the potential fermentation yields of these hydrolysate products using metabolic models of Escherichia coli, Saccharomyces cerevisiae wild type, Saccharomyces cerevisiae RN1016 with xylose isomerase and Clostridium acetobutylicum. We found that %Acid plays the most significant role and treatment time the least significant role in affecting the monosaccharaides released from Ulva biomass. We also found that within the tested range of parameters, hydrolysis with 121 °C, 30 min 2% Acid, 15% Solids could lead to the highest yields of conversion: 54.134-57.500 gr ethanol kg(-1) Ulva dry weight by S. cerevisiae RN1016 with xylose isomerase. Our results support optimized marine algae utilization process design and will enable smart energy harvesting by thermochemical hydrolysis.

Investigation of the optimal percentage of green seaweed that may be co-digested with dairy slurry to produce gaseous biofuel.

Science.gov (United States)

Allen, Eoin; Wall, David M; Herrmann, Christiane; Murphy, Jerry D

2014-10-01

Ulva lactuca, a green seaweed, accumulates on beaches and shallow estuaries subject to eutrophication. As a residue, and a macro-algae, it is a source of sustainable third generation biofuel. Production of biomethane from mono-digestion of U. lactuca, however is problematic due to high levels of sulphur and low ratios of carbon to nitrogen. Fresh and dried U. lactuca were continuously co-digested with dairy slurry at ratios of 25%, 50% and 75% (by volatile solid content) in 6 number 5L reactors for 9months. The reactors digesting a mix with 75% U. lactuca struggled to reach stable conditions. Volatile fatty acid levels of 14,000mgl(-1) were experienced. The levels of ammonia increased with percentage U. lactuca in the mix. Optimum conditions were observed with a mix of 25% fresh U. lactuca and 75% slurry. A yield of 170LCH4kg(-1)VS was achieved at an organic loading rate of 2.5kgVSm(-3)d(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

Cloning and characterization of nitrate reductase gene in Ulva prolifera (Ulvophyceae, Chlorophyta).

Science.gov (United States)

Guo, Yang; Wang, Hao Zhe; Wu, Chun Hui; Fu, Hui Hui; Jiang, Peng

2017-10-01

Ulva spp. dominates green tides around the world, which are occurring at an accelerated rate. The competitive nitrogen assimilation efficiency in Ulva is suggested to result in ecological success against other seaweeds. However, molecular characterization of genes involved in nitrogen assimilation has not been conducted. Here, we describe the identification of the nitrate reductase (NR) gene from a green seaweed Ulva prolifera, an alga which is responsible for the world's largest green tide in the Yellow Sea. Using rapid amplification of cDNA ends and genome walking, the NR gene from U. prolifera (UpNR) was cloned, which consisted of six introns and seven exons encoding 863 amino acids. According to sequence alignment, the NR in U. prolifera was shown to possess all five essential domains and 21 key invariant residues in plant NRs. The GC content of third codon position of UpNR (82.75%) was as high as those of green microalgae, and the intron number supported a potential loss issue from green microalga to land plant. Real-time quantitative PCR results showed that UpNR transcript level was induced by nitrate and repressed by ammonium, which could not be removed by addition of extra nitrate, indicating that U. prolifera preferred ammonium to nitrate. Urea would not repress NR transcription by itself, while it weakened the induction effect of nitrate, implying it possibly inhibited nitrate uptake rather than nitrate reduction. These results suggest the use of UpNR as a gene-sensor to probe the N assimilation process in green tides caused by Ulva. © 2017 Phycological Society of America.

Inhibition of hydrogen peroxide induced injuring on human skin fibroblast by Ulva prolifera polysaccharide.

Science.gov (United States)

Cai, Chuner; Guo, Ziye; Yang, Yayun; Geng, Zhonglei; Tang, Langlang; Zhao, Minglin; Qiu, Yuyan; Chen, Yifan; He, Peimin

2016-10-01

Ulva prolifera can protect human skin fibroblast from being injured by hydrogen peroxide. This work studied the composition of Ulva prolifera polysaccharide and identified its physicochemical properties. The results showed that the cell proliferation of 0.5mg/mL crude polysaccharide was 154.4% of that in negative control group. Moreover, ROS detection indices, including DCFH-DA, GSH-PX, MDA and CAT, indicated that crude polysaccharide could improve cellular ability to scavenge free radical and decrease the injury on human skin fibroblast by hydrogen peroxide. In purified polysaccharide, the activity of fraction P1-1 was the highest, with 174.6% of that in negative control group. The average molecular weight of P1-1 was 137kD with 18.0% of sulfate content. This work showed the inhibition of hydrogen peroxide induced injuries on human skin fibroblast by Ulva prolifera polysaccharide, which may further evaluate the application of U. prolifera on cosmetics. Copyright © 2016 Elsevier B.V. All rights reserved.

KERTAS SENI BERBAHAN LIMBAH PEWARNA ALAM RUMPUT LAUT JENIS SARGASSUM, ULVA DAN PELEPAH PISANG ABAKA

Directory of Open Access Journals (Sweden)

Guring Briegel Mandegani

2016-06-01

Full Text Available ABSTRAKKertas seni merupakan kerajinan tangan dengan bahan dasar berbagai macam tanaman berserat. Serat pisang abaka, serat jerami dan serat padi telah mampu diolah menjadi kertas seni secara mandiri tanpa bahan perekat tambahan. Selama ini industri kertas seni yang ada sebagian besar menggunakan bahan baku pelepah pisang raja, pisang abaka, jerami, serat padi dan sebagainya. Oleh karena itu, perlu adanya peningkatan keanekaragaman bahan baku, di antaranya dengan memanfaatkan material dari rumput laut maupun limbah rumput laut limbah pewarna alam tekstil. Tujuan dari penelitian ini adalah untuk mengetahui karakter kertas seni yang terbuat dari limbah pewarna alam dari rumput laut Sargassum sp. dan Ulva serta kombinasinya dengan material serat pisang abaka. Bahan baku pelepah pisang abaka dan limbah rumput laut diolah dengan cara pencacahan dengan ukuran 2-3 cm, direbus dengan soda api selama 2 jam, kemudian disaring dan didinginkan. Bahan kemudian saling dikombinasi dan dijadikan pulp menggunakan mesin blender. Pulp kemudian dicetak dan dianalisis secara fisik. Limbah rumput laut jenis Sargassum sp. dan Ulva dalam keadaan murni (100% tidak dapat digunakan sebagai bahan pembuatan produk kertas seni, dikarenakan kandungan selulosa yang masih di bawah 40% sehingga kertas yang dihasilkan dari proses pencetakan bersifat rapuh, mudah sobek dan tidak rekat antara satu dengan yang lain. Sedangkan kertas dengan campuran serat pisang abaka, menghasilkan kualitas kertas seni dengan kekuatan fisik yang lebih baik daripada kertas seni murni dari rumput laut Sargassum sp. dan Ulva. Kata Kunci: kertas seni, rumput laut, Sargassum sp., Ulva, pisang abaka  ABSTRACTPaper art is a craft that uses a wide variety of fibrous plants. Abaca, straw and rice fibers can be processed into paper art independently without additional adhesive material. During this time, the existing art paper industries use many raw materials such as banana, abaca, etc., Therefore, it is

Effector-mediated discovery of a novel resistance gene against Bremia Lactucae in a nonhost lettuce species

NARCIS (Netherlands)

Giesbers, A.K.J.; Pelgrom, Alexandra; Visser, R.G.F.; Niks, R.E.; Ackerveken, Van Den Guido; Jeuken, M.J.W.

2017-01-01

Candidate effectors from lettuce downy mildew (Bremia lactucae) enable high-throughput germplasm screening for the presence of resistance (R) genes. The nonhost species Lactuca saligna comprises a source of B. lactucae R genes that has hardly been exploited in lettuce breeding. Its

Effector-mediated discovery of a novel resistance gene against Bremia lactucae in a nonhost lettuce species

NARCIS (Netherlands)

Giesbers, Anne K J; Pelgrom, Alexandra J E; Visser, Richard G F; Niks, Rients E; Van den Ackerveken, Guido; Jeuken, Marieke J W

2017-01-01

Candidate effectors from lettuce downy mildew (Bremia lactucae) enable high-throughput germplasm screening for the presence of resistance (R) genes. The nonhost species Lactuca saligna comprises a source of B. lactucae R genes that has hardly been exploited in lettuce breeding. Its

Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion

DEFF Research Database (Denmark)

Bangsø Nielsen, Henrik; Heiske, Stefan

2011-01-01

In the present study we tested four macroalgae species – harvested in Denmark – for their suitability of bioconversion to methane. In batch experiments (53 WC) methane yields varied from 132 ml g volatile solids1 (VS) for Gracillaria vermiculophylla, 152 ml g VS1 for Ulva lactuca, 166 ml g VS1...

The seeding and cultivation of a tropical species of filamentous Ulva for algal biomass production.

Directory of Open Access Journals (Sweden)

Christina Carl

Full Text Available Filamentous species of Ulva are ideal for cultivation because they are robust with high growth rates and maintained across a broad range of environments. Temperate species of filamentous Ulva are commercially cultivated on nets which can be artificially 'seeded' under controlled conditions allowing for a high level of control over seeding density and consequently biomass production. This study quantified for the first time the seeding and culture cycle of a tropical species of filamentous Ulva (Ulva sp. 3 and identified seeding density and nursery period as key factors affecting growth and biomass yield. A seeding density of 621,000 swarmers m(-1 rope in combination with a nursery period of five days resulted in the highest growth rate and correspondingly the highest biomass yield. A nursery period of five days was optimal with up to six times the biomass yield compared to ropes under either shorter or longer nursery periods. These combined parameters of seeding density and nursery period resulted in a specific growth rate of more than 65% day(-1 between 7 and 10 days of outdoor cultivation post-nursery. This was followed by a decrease in growth through to 25 days. This study also demonstrated that the timing of harvest is critical as the maximum biomass yield of 23.0 ± 8.8 g dry weight m(-1 (228.7 ± 115.4 g fresh weight m(-1 was achieved after 13 days of outdoor cultivation whereas biomass degraded to 15.5 ± 7.3 g dry weight m(-1 (120.2 ± 71.8 g fresh weight m(-1 over a longer outdoor cultivation period of 25 days. Artificially seeded ropes of Ulva with high biomass yields over short culture cycles may therefore be an alternative to unattached cultivation in integrated pond-based aquaculture systems.

Quantitative, molecular and growth analyses of Ulva microscopic propagules in the coastal sediment of Jiangsu province where green tides initially occurred.

Science.gov (United States)

Liu, Feng; Pang, Shao Jun; Zhao, Xiao Bo; Hu, Chuan Ming

2012-03-01

From 2007 to 2011, large-scale green tides formed by unattached filamentous alga, Ulva prolifera in Ulva linza-procera-prolifera complex, have initially occurred in Jiangsu coasts of China. The real niche or the substrate(s) on which U. prolifera attaches before it starts to float is still under debate. However, great numbers of Ulva propagules would be supposed to exist in the microscopic, overwintering stage for the next spring's bloom in coastal environments. This study was designed to confirm the above prediction and investigate abundance, species composition and growth characteristics of Ulva propagules in the sediments. Quantification result showed that Ulva propagules widely distributed in the sediments and the abundance of these isolates did not change much over a 3-month testing period at low temperature in darkness. Molecular data based on three DNA markers revealed that four Ulva species existed in the sediments, among which green-tide forming alga, U. prolifera, was included. Elevated levels of temperature, irradiance as well as nutrients in seawater greatly facilitated recovery and growth of propagules. Results of this investigation indicated the possibility of microscopic propagules turning directly into floating biomass in season when temperature, irradiance and nutrients together meet the required levels in questioned coastal water area. Copyright © 2011 Elsevier Ltd. All rights reserved.

INFLUENCIA DE LAS CONDICIONES DE INCUBACIÓN SOBRE LA ACTIVACIÓN DE ZOOSPORAS DE Spongospora subterranea, EN BUSCA DE UN INÓCULO PARA EL ESTUDIO DE LA SARNA POLVOSA INFLUENCE OF INCUBATION CONDITIONS ON THE ACTIVATION OF ZOOSPORES OF Spongospora subterranea, SEARCHING FOR AN INOCULUM TO THE STUDY OF THE POWDERY SCAB

Directory of Open Access Journals (Sweden)

Edgar Beltrán Sánchez

2009-12-01

Full Text Available La sarna polvosa es una enfermedad que decrece la producción de papa. Es causada por el parásito obligado Spongospora subterranea f. sp. subterranea, el cual produce grupos de zoosporas enquistadas llamados quistosoros. Cuando las zoosporas están activas pueden infectar raíces y tubérculos iniciando un nuevo ciclo reproductivo. Para estudiar la influencia de las condiciones de incubación sobre la activación de las zoosporas, suspensiones acuosas de quistosoros fueron incubadas bajo diferentes condiciones. Los quistosoros y las zoosporas activas fueron diariamente contados utilizando microscopio óptico. El mayor número de zoosporas activas se encontró al cuarto día de incubación, mientras que el menor número de quistosoros se registró al quinto día de incubación. Esto sugiere que las zoosporas permanecen activas por un corto periodo. El número de zoosporas activas por quistosoro fue significativamente (PThe powdery scab is a disease that decreases potato production. It is caused by Spongospora subterranea f. sp. subterranea. This obligate parasite produces cystosori, which are groups of encysted zoospores. When these zoospores are active, they can infect roots and tubers initiating a new replication cycle. To investigate the influence of the incubation conditions on the zoospore activation, suspensions of cystosori in water were incubated under different conditions. The cystosori and the active zoospores were daily counted under microscope. The higher number of active zoospores was found after four days of incubation, meanwhile the lower number of cystosori was found after five days of incubation. This suggests that zoospores are active for a short period. The number of active zoospores per cystosorus was significantly (P<0.05 higher in tap water than in distillated water, and in presence of light than in dark. More zoospores per cystosorus were activated at 19 °C than at 5 °C, but potato roots did not have a significant (P<0

Ecological studies of Ulva reticulata Forsskal in Chapora bay (Goa)

Digital Repository Service at National Institute of Oceanography (India)

Untawale, A.G.; Dhargalkar, V.K.

The patchy occurrence of Ulva reticulata Forskal along the west coast of India lead to its ecological studies. The total annual yield of . reticulata calculated for 3800 sq. m. area of the bay amounts to 6.74 tonnes wet weight and 0.932 tonnes dry...

Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

Directory of Open Access Journals (Sweden)

Hanan M. Khairy

2013-05-01

Full Text Available Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta,Jania rubens (Linnaeus J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin Bornet(Rhodophyta were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied parameters in the three species. Pterocladia capillacea was characterized by the highest protein andcarbohydrate content throughout the different seasons, whereas Ulva lactuca contained more lipids (4.09 ± 0.2% than J. rubens and P. capillacea. The highest total fatty acids were recorded in J. rubens during the three seasons, while saturated fatty acids were predominant in P. capillacea during spring. This is due mainly to the presence of palmitic acid(C16:0, which made up 74.3% of the saturated fatty acids. The highest level of polyunsaturated fatty acids (PUFA in these algae was measured in J. rubens; DHA (22:6ω3 was the main acid, making up 26.4% of the total fatty acids especiallyduring summer. Proline was the major component of the amino acids in the three algal species, with maximum amounts in U. lactuca.

Antibacterial activity of Ulva reticulata from southwest coast of Kanyakumari, India

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Sundaram Ravikumar

2016-03-01

Full Text Available Objective: To evaluate the antibacterial activity of Ulva reticulata species collected from the Kanyakumari coast of India to determine their potential for bioactivity. Methods: The algal extract was prepared using n-butanol for evaluating the antibacterial activity of Salmonella typhi, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Vibrio cholerae, Vibrio parahaemolyticus, Bacillus cereus and Listeria monocytogenes. Results: It was observed that the n-butanolic extract of the seaweed powder of Ulva reticulata (25–100 mg/mL exerted notable antibacterial activity against tested bacterial strains. The maximum antibacterial activity was exhibited against Escherichia coli and Bacillus cereus in all concentrations. Conclusions: The results obtained in the present investigation supported the traditional use of the seaweeds against various infections. However, further investigation has been carried out to elucidate the exact mechanism and isolation of active principle.

948 15 N as a tool to demonstrate the contribution of fish-waste ...

African Journals Online (AJOL)

This study uses stable isotope ratios of nitrogen (ä15N) to test the hypothesis that a bloom of the green seaweed Ulva lactuca, which occurred in Saldanha Bay, South Africa, in summer 1993/94 was linked to an adjacent discharge of nitrogen from pelagic fish processing waste. It is suggested that only two significant ...

Energy Production from Marine Biomass (Ulva lactuca)

DEFF Research Database (Denmark)

Nikolaisen, Lars; Daugbjerg Jensen, Peter; Svane Bech, Karin

The background for this research activity is that the 2020 goals for reduction of the CO2 emissions to the atmosphere are so challenging that exorbitant amounts of biomass and other renewable sources of energy must be mobilised in order to – maybe – fulfil the ambitious 2020 goals. The macroalgae...... is an unexploited, not researched, not developed source of biomass and is at the same time an enormous resource by mass. It is therefore obvious to look into this vast biomass resource and by this report give some of the first suggestions of how this new and promising biomass resource can be exploited....

Effector-mediated discovery of a novel resistance gene against Bremia lactucae in a nonhost lettuce species.

Science.gov (United States)

Giesbers, Anne K J; Pelgrom, Alexandra J E; Visser, Richard G F; Niks, Rients E; Van den Ackerveken, Guido; Jeuken, Marieke J W

2017-11-01

Candidate effectors from lettuce downy mildew (Bremia lactucae) enable high-throughput germplasm screening for the presence of resistance (R) genes. The nonhost species Lactuca saligna comprises a source of B. lactucae R genes that has hardly been exploited in lettuce breeding. Its cross-compatibility with the host species L. sativa enables the study of inheritance of nonhost resistance (NHR). We performed transient expression of candidate RXLR effector genes from B. lactucae in a diverse Lactuca germplasm set. Responses to two candidate effectors (BLR31 and BLN08) were genetically mapped and tested for co-segregation with disease resistance. BLN08 induced a hypersensitive response (HR) in 55% of the L. saligna accessions, but responsiveness did not co-segregate with resistance to Bl:24. BLR31 triggered an HR in 5% of the L. saligna accessions, and revealed a novel R gene providing complete B. lactucae race Bl:24 resistance. Resistant hybrid plants that were BLR31 nonresponsive indicated other unlinked R genes and/or nonhost QTLs. We have identified a candidate avirulence effector of B. lactucae (BLR31) and its cognate R gene in L. saligna. Concurrently, our results suggest that R genes are not required for NHR of L. saligna. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

The effects of feedstock pre-treatment and pyrolysis temperature on the production of biochar from the green seaweed Ulva.

Science.gov (United States)

Roberts, David A; de Nys, Rocky

2016-03-15

Green seaweeds from the genus Ulva are a promising feedstock for the production of biochar for carbon (C) sequestration and soil amelioration. Ulva can be cultivated in waste water from land-based aquaculture and Ulva blooms ("green tides") strand millions of tons of biomass on coastal areas of Europe and China each year. The conversion of Ulva into biochar could recycle C and nutrients from eutrophic water into agricultural production. We produce biochar from Ulva ohnoi, cultivated in waste water from an aquaculture facility, and characterize its suitability for C sequestration and soil amelioration through bio-chemical analyses and plant growth experiments. Two biomass pre-treatments (fresh water rinsing to reduce salt, and pelletisation to increase density) were crossed with four pyrolysis temperatures (300-750 °C). Biomass rinsing decreased the ash and increased the C content of the resulting biochar. However, biochar produced from un-rinsed biomass had a higher proportion of fixed C and a higher yield. C sequestration decreased with increasing pyrolysis temperatures due to the combination of lower yield and lower total C content of biochar produced at high temperatures. Biochar produced from un-rinsed biomass at 300 °C had the greatest gravimetric C sequestration (110-120 g stable C kg(-1) seaweed). Biochar produced from un-pelletised Ulva enhanced plant growth three-fold in low fertility soils when the temperature of pyrolysis was less than 450 °C. The reduced effectiveness of the high-temperature biochars (>450 °C) was due to a lower N and higher salt content. Soil ameliorated with biochar produced from pelletised biomass had suppressed plant germination and growth. The most effective biochar for C sequestration and soil amelioration was produced from un-rinsed and un-pelletised Ulva at 300 °C. The green tide that occurs annually along the Shandong coastline in China generates sufficient biomass (200,000 tons dry weight) to ameliorate 12,500�

Changes in N cycling induced by Ulva detritus enrichment of sediments

DEFF Research Database (Denmark)

Garcia-Robledo, Emilio; Revsbech, Niels Peter; Risgaard-Petersen, Nils

2013-01-01

Macroalgal accumulation and decomposition in shallow water environments typically result in an increase in the organic matter content of the sediment, affecting both benthic metabolism and nutrient dynamics. The present study investigates how a pulse addition of Ulva detritus to estuarine sedimen...

Growth and Cell Cycle of ULVA Compressa (Ulvophyceae) under Led Illumination

Czech Academy of Sciences Publication Activity Database

Kuwano, K.; Abe, N.; Nishi, Y.; Seno, H.; Nishihara, G.N.; Iima, M.; Zachleder, Vilém

2014-01-01

Roč. 50, č. 2 (2014), s. 744-752 ISSN 0022-3646 Grant - others:Ministry of Education, Science and Culture(JP) 22580379 Institutional support: RVO:61388971 Keywords : cell cycle * ulva * elongation Subject RIV: EE - Microbiology, Virology Impact factor: 2.844, year: 2014

Anxiolytic property of hydro-alcohol extract of Lactuca sativa and its effect on behavioral activities of mice.

Science.gov (United States)

Harsha, Singapura Nagesh; Anilakumar, Kandangath Raghavan

2013-01-01

Lactuca sativa, belonging to the Asteraceae family, is a leafy vegetable known for its medicinal properties. This study aimed to understand the mechanism of Lactuca sativa extract with respect to pharmacological action.We investigated the anxiolytic effects of hydro-alcoholic extract of leaves of Lactuca sativa on mice. The behavioral tests performed on mice models to assess anti-anxiety properties were: open field test (OFT), elevated plus maze test (EPM), elevated T maze test, and marble burying test. Increased locomotor activity and time spent in the "open-arm" were observed in extract fed group. Malondialdehyde (MDA) and nitrite levels were decreased, catalase and glutathione levels were increased in Lactuca sativa treated mice. The data obtained in the present study suggests that the extract of Lactuca sativa can afford significant protection against anxiolytic activity.

Feeding trials of green seaweed Ulva fasciata

OpenAIRE

Alam, J.M.; Qasim, R.

1993-01-01

For the nutritional evaluation of green seaweed Ulva fasciata, a feeding trial was performed in albino rats. The results indicated that the 20% replacement of seaweed U. fasciata instead of carrot or lettuce in rad diet causes no harmful effects, as evident by a non-significant change in blood constituents and serum enzyme levels. The weight gain observed in rats with U. fasciata diet was same as that of control diet. The true digestibility ratio of U. fasciata was 80.20% with carrot and 83.4...

Genetic dissection of nonhost resistance of wild lettuce, Lactuca saligna, to downy mildew

NARCIS (Netherlands)

Zhang, N.

2008-01-01

Lettuce downy mildew is the most destructive disease in lettuce (Lactuca spp.) cultivation and is caused by Bremia lactucae. The successful cross between its host L. sativa and the nonhost, L. saligna, and offers a rare chance to study the genetics of the nonhost resistance. From a set of 29

Synchronous fluorescence spectroscopy for studying extracellular organic substances of Ulva rigida C. Ag; Analisi spettroscopica per fluorescenza sincrona nello studio delle sostanze organiche extracellulari dell`Ulva rigida C. Ag

Energy Technology Data Exchange (ETDEWEB)

Ferrari, G.M. [IRSA, Marine Environment Unit, Ispra (Italy). Centro Comune di Ricerca; Targa, C. [Univ. degli studi, Venice (Italy). Dip. di scienze ambientali

1996-01-01

Experiments performed using Ulva rigida thalli and enriched culture solutions demonstrated that Ulva emits extra-cellular organic substances the complexity of which can be monitored by synchronous fluorescence spectroscopy. It was found that synchronous peak intensities hA (excitation at 270-280 nm), hB (340-350 nm) and hC (390-400 nm) varies in relation to the age of the thallus and the quality of the emitted substances by the alga. The peak height ratio hA/hB display an inverse relationship with the age of the alga and a direct relationship with the slope of the absorption curves. That occurs since hA, after a first increase, tends to diminish in correspondence to a progressive increase of the peaks hB and hC due to the emission of the more and more complex fluorescent organic substances.

Ulva biomass as a co-substrate for stable anaerobic digestion of spent coffee grounds in continuous mode.

Science.gov (United States)

Kim, Jaai; Kim, Hakchan; Lee, Changsoo

2017-10-01

Ulva biomass was evaluated as a co-substrate for anaerobic digestion of spent coffee grounds at varying organic loads (0.7-1.6g chemical oxygen demand (COD)/Ld) and substrate compositions. Co-digestion with Ulva (25%, COD basis) proved beneficial for SCG biomethanation in both terms of process performance and stability. The beneficial effect is much more pronounced at higher organic and hydraulic loads, with the highest COD removal and methane yield being 51.8% and 0.19L/g COD fed, respectively. The reactor microbial community structure changed dynamically during the experiment, and a dominance shift from hydrogenotrophic to aceticlastic methanogens occurred with increase in organic loading rate. Network analysis provides a comprehensive view of the microbial interactions involved in the system and confirms a direct positive correlation between Ulva input and methane productivity. A group of populations, including Methanobacterium- and Methanoculleus-related methanogens, was identified as a possible indicator for monitoring the biomethanation performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Analysis of essential oil extracted from Lactuca sativa seeds growing in Xinjiang by GC-MS].

Science.gov (United States)

Xu, Fang; Wang, Qiang; Haji, Akber Aisa

2011-12-01

To analyze the components of essential oil from Lactuca sativa seeds growing in Xinjiang. The components of essential oil from Lactuca sativa seeds were analyzed by gas chromatography-mass spectrometry (GC-MS). 62 components were identified from 71 separated peaks,amounting to total mass fraction 95.07%. The dominant compounds were n-Hexanol (36.31%), n-Hexanal (13.71%), trans-2-Octen-l-ol (8.09%) and 2-n-Pentylfuran (4.41%). The research provides a theoretical basis for the exploitation and use of Lactuca sativa seeds resource.

Effects of Seaweed Substitution on Breadmaking. : (IV) Ulva pertusa

OpenAIRE

筒井, 知己; 金井, 節子; 牛腸, ヒロミ; 小見山, 二郎; ツツイ, トモミ; カナイ, セツコ; ゴチョウ, ヒロミ; コミヤマ, ジロウ; TOMOMI, TSUTSUI; SETSUKO, KANAI; HIROMI, GOCHO; JIRO, KOMIYAMA

2003-01-01

Physical properties of wheat flour replaced with 0.5 to 1.5 % of seaweed Ulva pertusa (WFRS) and baking properties of them were estimated. Water absorption capacity of WFRS increased gradually as seaweed level increased. Among the bread made from WFRS, the bread made from wheat flour replaced with 0.5% of seaweed showed better loaf volume and also showed better sensory evaluation score. Electronic nose analysis concurred with sensory descriptor ratings.

A taxonomic revision of the genus lactuca L. (cicihorieae- asteraceae) from Pakistan and Kashmir

International Nuclear Information System (INIS)

Qaiser, M.; Bano, R.

2011-01-01

The genus Lactuca L. of the tribe Cichorieae-Asteraceae is taxonomically revised from Pakistan and Kashmir. The revision is based on study of large number of herbarium specimens. In few cases plants have also been studied in their natural habitat. A total of 13 species are recognized from Pakistan and Kashmir including 1 new species i.e. Lactuca erostrata Roohi Bano and Qaiser. A new combination Lactuca orientalis subsp. nuristanica (Podlech) Roohi Bano and Qaiser is also proposed. All the taxa valid or synonyms have been typified with the help of type specimens and literature. Key to the species along with detailed morphological description and ecological notes of each taxon are also given. (author)

Saturating light and not increased carbon dioxide under ocean acidification drives photosynthesis and growth in Ulva rigida (Chlorophyta)

Science.gov (United States)

Rautenberger, Ralf; Fernández, Pamela A; Strittmatter, Martina; Heesch, Svenja; Cornwall, Christopher E; Hurd, Catriona L; Roleda, Michael Y

2015-01-01

Carbon physiology of a genetically identified Ulva rigida was investigated under different CO2(aq) and light levels. The study was designed to answer whether (1) light or exogenous inorganic carbon (Ci) pool is driving growth; and (2) elevated CO2(aq) concentration under ocean acidification (OA) will downregulate CAext-mediated dehydration and alter the stable carbon isotope (δ13C) signatures toward more CO2 use to support higher growth rate. At pHT 9.0 where CO2(aq) is Ulva found putative light-dependent transporters to which the remaining NPS can be attributed. The shift in δ13C signatures from –22‰ toward –10‰ under saturating light but not under elevated CO2(aq) suggest preference and substantial use to support photosynthesis and growth. U. rigida is Ci saturated, and growth was primarily controlled by light. Therefore, increased levels of CO2(aq) predicted for the future will not, in isolation, stimulate Ulva blooms. PMID:25750714

Phthalate esters in marine algae

OpenAIRE

Gezgin, Tuncay; Güven, Kasim Cemal; Akçin, Göksel

2001-01-01

Abstract o-Phthalate esters as diethyl phthalate, dibutyl phthalate, di-isobutyl phthalate and diethylhexyl phthalate were identified at surface and inner part of algae collected in the Bosphorus, as Ulva lactuca, Enteromorpha linza, Cystoseria barbata, Pterocladia capillaceaeand Ceramium rubrum. The same esters were also detected in seawater samples taken from the same area. Thus parallelism in pollution was noted between the algae and the surrounding seawater,

Sulphur fate and anaerobic biodegradation potential during co-digestion of seaweed biomass (Ulva sp.) with pig slurry.

Science.gov (United States)

Peu, P; Sassi, J-F; Girault, R; Picard, S; Saint-Cast, Patricia; Béline, F; Dabert, P

2011-12-01

Seaweed (Ulva sp.) stranded on beaches were utilized as co-substrate for anaerobic digestion of pig slurry in three-month co-digestion tests in pilot scale anaerobic digesters in the laboratory. The methanogenic potential of Ulva sp. was low compared to that of other potential co-substrates available for use by farmers: 148 N m3CH4/t of volatile solids or 19 N m3CH4/t of crude product. When used as a co-substrate with pig manure (48%/52% w/w), Ulva sp. seaweed did not notably disrupt the process of digestion; however, after pilot stabilisation, biogas produced contained 3.5% H2S, making it unsuitable for energy recovery without treatment. Sequentially addition of the sulphate reduction inhibitor, potassium molybdate, to a final concentration of 3mM, temporarily reduced H2S emissions, but was unable to sustain this reduction over the three-month period. According to these pilot tests, the use of seaweed stranded on beaches as co-substrate in farm-based biogas plants shows some limitations. Copyright © 2011 Elsevier Ltd. All rights reserved.

Wild lettuce (Lactuca virosa) toxicity

OpenAIRE

Besharat, Sima; Besharat, Mahsa; Jabbari, Ali

2009-01-01

Wild lettuce (Lactuca virosa) can cause toxic effects when eaten. Wild lettuce grows in the north of Iran and some natives consume it unaware of its adverse side effects. We describe eight patients with manifestations of wild lettuce toxicity, admitted to a general hospital affiliated to the Golestan University of Medical Sciences. All the patients recovered (although one had to spend 48 h in the intensive care unit) and no chronic complications were reported. A clinical suspicion of toxicity...

Changes in Microtubular Alignment in Lactuca spp. (Asteraceae) Epidermal Cells during Early Stages of Infection by Bremia lactucae (Peronosporaceae)

Czech Academy of Sciences Publication Activity Database

Sedlářová, M.; Binarová, Pavla; Lebeda, A.

2001-01-01

Roč. 41, č. 1 (2001), s. 21-34 ISSN 0079-2047 R&D Projects: GA AV ČR IAA5020803; GA MŠk ME 397 Institutional research plan: CEZ:AV0Z5038910 Keywords : Bremia lactuca e * Peronosporaceae * resistance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.275, year: 2001

Polyunsaturated fatty acids in various macroalgal species from north Atlantic and tropical seas

OpenAIRE

van Ginneken, Vincent JT; Helsper, Johannes PFG; de Visser, Willem; van Keulen, Herman; Brandenburg, Willem A

2011-01-01

Abstract Background In this study the efficacy of using marine macroalgae as a source for polyunsaturated fatty acids, which are associated with the prevention of inflammation, cardiovascular diseases and mental disorders, was investigated. Methods The fatty acid (FA) composition in lipids from seven sea weed species from the North Sea (Ulva lactuca, Chondrus crispus, Laminaria hyperborea, Fucus serratus, Undaria pinnatifida, Palmaria palmata, Ascophyllum nodosum) and two from tropical seas (...

Isolation of a lactic acid bacterium and yeast consortium from a fermented material of Ulva spp. (Chlorophyta).

Science.gov (United States)

Uchida, M; Murata, M

2004-01-01

Microbiota in a fermented culture of Ulva spp. was examined with the objective to characterize the type of fermentation and to obtain starter microbes for performing seaweed fermentation. Fermented Ulva spp. cultures which were obtained and transferred in a laboratory were examined for their microbiota. With phenotypic characterization and phylogenetic analysis based on rRNA gene nucleotide sequences, the predominant micro-organisms were identified as Lactobacillus brevis, Debaryomyces hanseni var. hansenii, and a Candida zeylanoides-related specimen, suggesting that the observed fermentation can be categorized to lactic acid and ethanol fermentation. Inoculating the individually cultured cell suspensions of the three kinds of micro-organisms with cellulase induced the fermentation in various kinds of seaweed. A microbial consortium composed of a lactic acid bacterium, L. brevis, and yeasts, D. hansenii and a C. zeylanoides-related specimen, were predominant in a fermented culture of Ulva spp. Lactic acid and ethanol fermentation could be induced in various kinds of seaweed by adding this microbial consortium along with cellulase. This is the first report of lactic acid and ethanol fermentation in seaweed, which is expected to provide a new material for food and dietary applications.

Genetic dissection of nonhost resistance of wild lettuce, Lactuca saligna, to downy mildew

OpenAIRE

Zhang, N.

2008-01-01

Lettuce downy mildew is the most destructive disease in lettuce (Lactuca spp.) cultivation and is caused by Bremia lactucae. The successful cross between its host L. sativa and the nonhost, L. saligna, and offers a rare chance to study the genetics of the nonhost resistance. From a set of 29 Backcross Inbred Lines (BILs) representing in total 96% of the L. saligna genome, 15 introgressions were identified to contribute to this resistance at one to four tested lettuce developmental stages and ...

Anaerobic digestion of macroalgae: methane potentials, pre-treatment, inhibition and co-digestion.

Science.gov (United States)

Nielsen, H B; Heiske, S

2011-01-01

In the present study we tested four macroalgae species--harvested in Denmark--for their suitability of bioconversion to methane. In batch experiments (53 degrees C) methane yields varied from 132 ml g volatile solids(-1) (VS) for Gracillaria vermiculophylla, 152 mi gVS(-1) for Ulva lactuca, 166 ml g VS(-1) for Chaetomorpha linum and 340 ml g VS(-1) for Saccharina latissima following 34 days of incubation. With an organic content of 21.1% (1.5-2.8 times higher than the other algae) S. latissima seems very suitable for anaerobic digestion. However, the methane yields of U. lactuca, G. vermiculophylla and C. linum could be increased with 68%, 11% and 17%, respectively, by pretreatment with maceration. U. lactuca is often observed during 'green tides' in Europe and has a high cultivation potential at Nordic conditions. Therefore, U. lactuca was selected for further investigation and co-digested with cattle manure in a lab-scale continuously stirred tank reactor. A 48% increase in methane production rate of the reactor was observed when the concentration of U. lactuca in the feedstock was 40% (VS basis). Increasing the concentration to 50% had no further effect on the methane production, which limits the application of this algae at Danish centralized biogas plant.

Two new mountainous species of Lactuca (Cichorieae, Asteraceae) from Iran, one presenting a new, possibly myrmecochorous achene variant.

Science.gov (United States)

Kilian, Norbert; Djavadi, Seyyedeh Bahereh; Eskandari, Majid

2012-01-01

It is shown that the concept of the Iranian endemic Lactuca polyclada in the sense of both its original author Boissier and its current use actually admixes two entirely different species, as was first noted by Beauverd a hundred years ago but has been neglected by later workers. One is a putative relative of Lactuca rosularis, the other was recognised by Beauverd as a member of the genus Cicerbita. The name Lactuca polyclada Boiss. is lectotypified here, maintaining its use as established by Beauverd for the Cicerbita species. Both species are morphologically delimited and mature achenes of Cicerbita polyclada are illustrated for the first time. The putative relative of Lactuca rosularis, a rare local endemic of the summit area of Kuh e-Dena, which has remained without a valid name by now, is described as a new species, Lactuca denaensis N. Kilian & Djavadi, and illustrated. A third member of the Lactuca rosularis group, Lactuca hazaranensis Djavadi & N. Kilian, discovered among a recent collection and apparently being a rare chasmophyte of the Hazaran mountain massif in the province of Kerman, Iran, is described as a species new to science, illustrated and delimited from the other two species. This new species has peculiar achenes representing a hitherto unknown variant: the body of the beaked achenes is divided into two segments by a transversal constriction in the distal third. The proximal segment contains the embryo, the distal segment is solid with a lipid-containing yellow tissue. The easily detachable pappus and the equally easily detachable beak potentially obstruct dispersal by wind. Since detachment of the beak also exposes the lipid-containing tissue of the distal segment, its potential as an elaiosome and myrmecochory as a possible mode of dispersal are discussed.

Pathway of /sup 14/Co/sub 2/ fixation in marine algae

Energy Technology Data Exchange (ETDEWEB)

Joshi, G V; Karekar, M D [Shivaji Univ., Kolhapur (India). Dept. of Botany

1973-08-01

Marine plants have a different metabolic environment which is likely to affect pathways of CO/sub 2/ fixation. It has been observed that in marine alga, Ulva lactuca, during short term light fixation of /sup 14/CO/sub 2/, besides PGA, an appreciable amount of activity was located in aspartate. This curious observation can now be explained on the basis of Hatch, Slack and Kortschak pathway of CO/sub 2/ fixation. In order to trace pathways of /sup 14/CO/sub 2/ in marine algae, a wide variety of algal specimens were exposed to NaH/sup 14/CO/sub 3/ in light and the products were analyzed. The algae selected were Ulva lactuca, Sargassum ilicifolium, Sphacelaria sp., Padina tetrastromatica, Chaetomorpha media and Enteromorpha tubulosa. It has been found that the pathways of CO/sub 2/ in the above marine algae differ from the conventional pattern recorded in Chlorella. The early labelling of aspartate and its subsequent utilization indicates that HSK pathway is operative in the marine algae. Malate synthesis is inhibited due to the effect of saline environment on the activity of malic dehydrogenase. Appreciable label in PGA is suggestive of the fact that Calvin and Bassham pathway as well as the HSK route are simultaneously operating. (auth)

Zooming in on the lettuce genome: species relationships in Lactuca s.l., inferred from chromosomal and molecular characters

NARCIS (Netherlands)

Koopman, W.J.M.

2002-01-01

Lactuca sativa (cultivated lettuce) is the world's most important leafy salad vegetable. Apart from L. sativa , the genus Lactuca contains ca. 75 wild species, potentially useful to improve, for example, taste, texture, and

Algal bioremediation of waste waters from land-based aquaculture using ulva: selecting target species and strains.

Directory of Open Access Journals (Sweden)

Rebecca J Lawton

Full Text Available The optimised reduction of dissolved nutrient loads in aquaculture effluents through bioremediation requires selection of appropriate algal species and strains. The objective of the current study was to identify target species and strains from the macroalgal genus Ulva for bioremediation of land-based aquaculture facilities in Eastern Australia. We surveyed land-based aquaculture facilities and natural coastal environments across three geographic locations in Eastern Australia to determine which species of Ulva occur naturally in this region and conducted growth trials at three temperature treatments on a subset of samples from each location to determine whether local strains had superior performance under local environmental conditions. DNA barcoding using the markers ITS and tufA identified six species of Ulva, with U. ohnoi being the most common blade species and U. sp. 3 the most common filamentous species. Both species occurred at multiple land-based aquaculture facilities in Townsville and Brisbane and multiple strains of each species grew well in culture. Specific growth rates of U. ohnoi and U. sp. 3 were high (over 9% and 15% day(-1 respectively across temperature treatments. Within species, strains of U. ohnoi had higher growth in temperatures corresponding to local conditions, suggesting that strains may be locally adapted. However, across all temperature treatments Townsville strains had the highest growth rates (11.2-20.4% day(-1 and Sydney strains had the lowest growth rates (2.5-8.3% day(-1. We also found significant differences in growth between strains of U. ohnoi collected from the same geographic location, highlighting the potential to isolate and cultivate fast growing strains. In contrast, there was no clearly identifiable competitive strain of filamentous Ulva, with multiple species and strains having variable performance. The fast growth rates and broad geographical distribution of U. ohnoi make this an ideal species to

Aqueous-Based Fabrication of Low-VOC Nanostructured Block Copolymer Films as Potential Marine Antifouling Coatings.

Science.gov (United States)

Kim, Kris S; Gunari, Nikhil; MacNeil, Drew; Finlay, John; Callow, Maureen; Callow, James; Walker, Gilbert C

2016-08-10

The ability to fabricate nanostructured films by exploiting the phenomenon of microphase separation has made block copolymers an invaluable tool for a wide array of coating applications. Standard approaches to engineering nanodomains commonly involve the application of organic solvents, either through dissolution or annealing protocols, resulting in the release of volatile organic compounds (VOCs). In this paper, an aqueous-based method of fabricating low-VOC nanostructured block copolymer films is presented. The reported procedure allows for the phase transfer of water insoluble triblock copolymer, poly(styrene-block-2 vinylpyridine-block-ethylene oxide) (PS-b-P2VP-b-PEO), from a water immiscible phase to an aqueous environment with the assistance of a diblock copolymeric phase transfer agent, poly(styrene-block-ethylene oxide) (PS-b-PEO). Phase transfer into the aqueous phase results in self-assembly of PS-b-P2VP-b-PEO into core-shell-corona micelles, which are characterized by dynamic light scattering techniques. The films that result from coating the micellar solution onto Si/SiO2 surfaces exhibit nanoscale features that disrupt the ability of a model foulant, a zoospore of Ulva linza, to settle. The multilayered architecture consists of a pH-responsive P2VP-"shell" which can be stimulated to control the size of these features. The ability of these nanostructured thin films to resist protein adsorption and serve as potential marine antifouling coatings is supported through atomic force microscopy (AFM) and analysis of the settlement of Ulva linza zoospore. Field trials of the surfaces in a natural environment show the inhibition of macrofoulants for 1 month.

Effects of ultraviolet radiation and temperature on the ultrastructure of zoospores of the brown macroalga Laminaria hyperborea.

Science.gov (United States)

Steinhoff, F S; Wiencke, C; Müller, R; Bischof, K

2008-05-01

The interactive effects of an 8 h exposure to UV radiation and altered temperatures on the ultrastructure and germination of zoospores of the sublittoral brown alga Laminaria hyperborea (Gunn.) Foslie were investigated for the first time. Spores were exposed to four temperatures (2, 7, 12 and 17 degrees C) and three light regimes (PAR, PAR + UV-A, PAR + UV-A+UV-B). Freshly-released spores of L. hyperborea lack a cell wall and contain a nucleus with fine granular nucleoplasm and a nucleolus, one chloroplast, several mitochondria, dictyosomes and an endoplasmatic reticulum. Further, several kinds of so-called adhesive vesicles, lipid globuli and physodes containing UV-absorbing phlorotannins are embedded in the cytoplasm. No eye-spot is present. Physodes were found but they were rare and small. After an 8 h exposure to UV-B, the nucleoplasm had a mottled structure, chloroplasts contained plastoglobuli, the structure of the mitochondria changed from crista- to sacculus-type and germination was strongly inhibited at all temperatures. UV-A only had an impact on the ultrastructure at the highest temperature tested. The strongest effects were found at 17 degrees C, where germination was reduced to 35%, 32% and 9% after exposure to PAR, PAR+UV-A and PAR + UV-A + UV-B, respectively. This study indicates that UV-B radiation has strong damaging effects on the physiology and ultrastructure of zoospores of L. hyperborea. The results are important for developing scenarios for the effect of enhanced UV radiation and increasing temperatures caused by global climate changes.

Sulfur isotope variability of oceanic DMSP generation and its contributions to marine biogenic sulfur emissions.

Science.gov (United States)

Oduro, Harry; Van Alstyne, Kathryn L; Farquhar, James

2012-06-05

Oceanic dimethylsulfoniopropionate (DMSP) is the precursor to dimethylsulfide (DMS), which plays a role in climate regulation through transformation to methanesulfonic acid (MSA) and non-seasalt sulfate (NSS-SO(4)(2-)) aerosols. Here, we report measurements of the abundance and sulfur isotope compositions of DMSP from one phytoplankton species (Prorocentrum minimum) and five intertidal macroalgal species (Ulva lactuca, Ulva linza, Ulvaria obscura, Ulva prolifera, and Polysiphonia hendryi) in marine waters. We show that the sulfur isotope compositions (δ(34)S) of DMSP are depleted in (34)S relative to the source seawater sulfate by ∼1-3‰ and are correlated with the observed intracellular content of methionine, suggesting a link to metabolic pathways of methionine production. We suggest that this variability of δ(34)S is transferred to atmospheric geochemical products of DMSP degradation (DMS, MSA, and NSS-SO(4)(2-)), carrying implications for the interpretation of variability in δ(34)S of MSA and NSS-SO(4)(2-) that links them to changes in growth conditions and populations of DMSP producers rather than to the contributions of DMS and non-DMS sources.

Uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida.

Science.gov (United States)

Cheney, Donald; Rajic, Ljiljana; Sly, Elizabeth; Meric, Dogus; Sheahan, Thomas

2014-11-15

The uptake of PCBs contained in marine sediments by the green macroalga Ulva rigida was investigated in both laboratory and field experiments. Under laboratory conditions, total PCBs (tPCBs) uptake was significantly greater in live vs dead plants. The concentration of tPCB taken up in live plants was greatest in the first 24h (1580 μg kg(-1) dry weight), and then increased at a lower rate from day 2 to 14. Dead plants had a significantly lower tPCB concentration after 24h (609 μg kg(-1) dry weight) and lower uptake rate through day 14. Lesser chlorinated PCB congeners (below 123) made up the majority of PCBs taken up. Congener composition in both laboratory and field experiments was correlated to congener logKow value and sediment content. Field experiments showed that Ulva plants could concentrate PCBs to 3.9 mg kg(-1) in 24h. Thus, U. rigida is capable of removing PCBs in sediments at a rapid rate. Copyright © 2014 Elsevier Ltd. All rights reserved.

Genetic transformation of lettuce ( Lactuca sativa ): A review | Dan ...

African Journals Online (AJOL)

Lettuce (Lactuca sativa L.) is a globally important leafy vegetable that can be grown worldwide. Due to the rapid growth of population and the human desire to progress, there have been a lot of studies made by researchers, especially in genetic engineering. Improvements in regeneration system and transformation ...

Seaweed-synthesized silver nanoparticles: an eco-friendly tool in the fight against Plasmodium falciparum and its vector Anopheles stephensi?

Science.gov (United States)

Murugan, Kadarkarai; Samidoss, Christina Mary; Panneerselvam, Chellasamy; Higuchi, Akon; Roni, Mathath; Suresh, Udaiyan; Chandramohan, Balamurugan; Subramaniam, Jayapal; Madhiyazhagan, Pari; Dinesh, Devakumar; Rajaganesh, Rajapandian; Alarfaj, Abdullah A; Nicoletti, Marcello; Kumar, Suresh; Wei, Hui; Canale, Angelo; Mehlhorn, Heinz; Benelli, Giovanni

2015-11-01

Malaria, the most widespread mosquito-borne disease, affects 350-500 million people each year. Eco-friendly control tools against malaria vectors are urgently needed. This research proposed a novel method of plant-mediated synthesis of silver nanoparticles (AgNP) using a cheap seaweed extract of Ulva lactuca, acting as a reducing and capping agent. AgNP were characterized by UV-vis spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The U. lactuca extract and the green-synthesized AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi. In mosquitocidal assays, LC50 values of U. lactuca extract against A. stephensi larvae and pupae were 18.365 ppm (I instar), 23.948 ppm (II), 29.701 ppm (III), 37.517 ppm (IV), and 43.012 ppm (pupae). LC50 values of AgNP against A. stephensi were 2.111 ppm (I), 3.090 ppm (II), 4.629 ppm (III), 5.261 ppm (IV), and 6.860 ppm (pupae). Smoke toxicity experiments conducted against mosquito adults showed that U. lactuca coils evoked mortality rates comparable to the permethrin-based positive control (66, 51, and 41%, respectively). Furthermore, the antiplasmodial activity of U. lactuca extract and U. lactuca-synthesized AgNP was evaluated against CQ-resistant (CQ-r) and CQ-sensitive (CQ-s) strains of Plasmodium falciparum. Fifty percent inhibitory concentration (IC50) values of U. lactuca were 57.26 μg/ml (CQ-s) and 66.36 μg/ml (CQ-r); U. lactuca-synthesized AgNP IC50 values were 76.33 μg/ml (CQ-s) and 79.13 μg/ml (CQ-r). Overall, our results highlighted out that U. lactuca-synthesized AgNP may be employed to develop newer and safer agents for malaria control.

TOXICITY PROPENSITIES OF SOME MARINE AND FRESH-WATERALGAE AS THEIR CHEMICAL DEFENSE

OpenAIRE

ORHAN, İlkay; WISESPONGPAND, Puntip; ATICI, Tahir; ŞENER, Bilge

2003-01-01

Five species of the marine brown-algae, namely Halopteris scoparia (L.) Sauvagau, Padina vickersiae Hoyt, Dictyota dichotoma (Huds) Lam., Scinaia furcellata L., and Sargassum natans (L.) J. Meyer, a species of the marine green-alga, Ulva lactuca L., a species of the sea grass, Posidonia oceanica L., six species of fresh-water green-algae, namely Vaucheria sessilis (Vauch.) De Candolle, Zygnema pectinatum (Vauch.) C.A. Agardh, Maugeotia sp. (C.A. Agardh) Wittrock, Cladophora fracta (Dilw.) Kti...

Seasonal variations in the biochemical composition of some common seaweed species from the coast of Abu Qir Bay, Alexandria, Egypt

OpenAIRE

Khairy, Hanan M.; El-Shafay, Shimaa M.

2013-01-01

Variations in protein, carbohydrate, lipid, ash, moisture, fatty acid and aminoacid contents of the seaweeds Ulva lactuca Linnaeus (Chlorophyta),Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet(Rhodophyta) were studied seasonally from spring to autumn 2010. The seaweeds were collected from a rocky site near Boughaz El-Maadya on the coast of Abu Qir Bay east of Alexandria, Egypt. Remarkable seasonal variations were recorded in the levels of the studied pa...

Effects of Lactuca sativa extract on exploratory behavior pattern, locomotor activity and anxiety in mice

Directory of Open Access Journals (Sweden)

S.N. Harsha

2012-05-01

Full Text Available Objective: To evaluate antianxiety property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties belongs to Asteraceae family. Methods: Elevated plus maze (EPM, open field test (OFT, rat exposure test, hyponeophagia and marble burying test were performed in mice models to assess the exploratory behaviour and to assess anxiolytic property of hydro-alcohol extract of Lactuca sativa. Diazepam (1 mg/kg body wt. served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and evaluated exploratory behaviour, locomotor and anxiolytic activities. Results: Time spent and number of entries into the open arm was measured in EPM followed by total locomotor activity in OFT and latency to enter the food zone in hyponeophagia. Conclusions: The study suggested that hydro-alcohol extract of Lactuca sativa leaves possess potent anxiolytic property.

Enzymatic hydrolysis and production of bioethanol from common macrophytic green alga Ulva fasciata Delile.

Science.gov (United States)

Trivedi, Nitin; Gupta, Vishal; Reddy, C R K; Jha, Bhavanath

2013-12-01

The green seaweed Ulva which proliferates fast and occurs abundantly worldwide was used as a feedstock for production of ethanol following enzymatic hydrolysis. Among the different cellulases investigated for efficient saccharification, cellulase 22119 showed the highest conversion efficiency of biomass into reducing sugars than Viscozyme L, Cellulase 22086 and 22128. Pre-heat treatment of biomass in aqueous medium at 120°C for 1h followed by incubation in 2% (v/v) enzyme for 36 h at 45°C gave a maximum yield of sugar 206.82±14.96 mg/g. The fermentation of hydrolysate gave ethanol yield of 0.45 g/g reducing sugar accounting for 88.2% conversion efficiency. These values are substantially higher than those of reported so far for both agarophytes and carrageenophytes. It was also confirmed that enzyme can be used twice without compromising on the saccharification efficiency. The findings of this study reveal that Ulva can be a potential feedstock for bioethanol production. Copyright © 2013 Elsevier Ltd. All rights reserved.

Heavy metal concentrations in macroalgae species from Sinop coasts of the Southern Black Sea

Directory of Open Access Journals (Sweden)

Levent Bat

2016-10-01

Full Text Available Objective: To determine the concentrations of Fe, Zn, Ni, Cu, Mn, Pb, Cd and Co in macroalgae from Sinop coasts of the Sounthern Black Sea. Methods: Chlorophyta-green algae (Chaetomorpha spp., Cladophora spp., Ulva linza, Ulva intestinalis, Ulva lactuca, Ulva rigida; Ochrophyta-brown alga [Cystoseira barbata (C. barbata] and Rhodophyta-red algae (Ceramium spp., Corallina panizzoi were collected seasonally in the year 2010 from the upper infralittoral zone of inner harbour, outer harbour, Gerze and Ayancık of Sinop coasts of the Black Sea. The samples were analysed by atomic absorption spectrophotometer in order to determine heavy metal levels in different algal division species along Sinop coasts and to provide information of marine environment quality as marine strategy framework directive is aimed to ensure good environmental status of the seas by 2020 in the European Union. Results: The results showed that metal concentrations in all studied green algae, brown alga and red algae increase in the order: Cd < Co < Ni < Pb < Cu < Zn < Mn < Fe, Cd < Co < Cu < Ni < Pb < Mn < Zn < Fe and Co < Cd < Ni < Cu < Pb < Mn < Zn < Fe, respectively. In all divisions, among the essential elements the highest concentrations exhibited by Fe, in Gerze station- (2328 ± 89 µg/g dry weight in Chaetomorpha spp.; (2143 ± 78 µg/g dry weight in C. barbata and (968 ± 20 µg/g dry weight in Ceramium spp. Conclusions: The highest accumulation of different metals in the analysed algae species were: Fe and Co in Chaetomorpha spp., Zn in C. barbata, Ni and Cu in Ulva linza, Mn in Ulva intestinalis, Pb and Cd in Corallina panizzoi.

Variation within Lactuca for resistance to Impatiens necrotic spot virus

Science.gov (United States)

Lettuce (Lactuca sativa L.) production in coastal California, one of the major lettuce-producing areas of the US, is affected by outbreaks of Impatiens necrotic spot virus (INSV) from the genus Tospovirus. Transmission of INSV among lettuce crops in this growing region has been attributed mostly to ...

An integrated interspecific AFLP map of lettuce (Lactuca) based on two L. Saligna x L. sativa F2-populations

NARCIS (Netherlands)

Jeuken, M.; Wijk, van R.; Peleman, J.; Lindhout, P.

2001-01-01

AFLP markers were obtained with 12 EcoRI/ MseI primer combinations on two independent F2 populations of Lactuca sativa 2 Lactuca saligna. The polymorphism rates of the AFLP products between the two different L. saligna lines was 39°between the two different L. sativa cultivars 13 nd between the L.

Phosphomannose isomerase gene for selection in lettuce (Lactuca sativa L.) transformation

Czech Academy of Sciences Publication Activity Database

Bříza, Jindřich; Růžičková, N.; Niedermeierová, Hana; Dusbábková, Jana; Vlasák, Josef

2010-01-01

Roč. 57, č. 1 (2010), s. 63-68 ISSN 0001-527X Institutional research plan: CEZ:AV0Z50510513 Keywords : pmi * npt II * Lactuca sativa Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.234, year: 2010

Influence of Salicylic Acid on the Growth of Lettuce (Lactuca sativa ...

African Journals Online (AJOL)

PROF HORSFALL

2018-04-10

Apr 10, 2018 ... Keywords: Water stress, Salicylic acid, Growth, Lactuca sativa. Water stress in plant is an ... processes in plant adaptation to drought stress as it synthesis and ... manure was added to the soil in the preparation for planting.

Freqüência de enteroparasitas em amostras de alface (Lactuca sativa comercializadas em Lavras, Minas Gerais Frequency of intestinal parasites in samples of lettuce (Lactuca sativa commercialized in Lavras, Minas Gerais State

Directory of Open Access Journals (Sweden)

Antônio Marcos Guimarães

2003-10-01

Full Text Available O objetivo deste trabalho foi realizar uma avaliação parasitológica em amostras de alface (Lactuca sativa comercializadas em Lavras, MG. As amostras de alfaces apresentaram baixos padrões higiênicos, indicados pela presença de formas parasitológicas de origem animal ou humana e alta concentração de coliformes fecais.The aim of this study was to evaluate the parasitological contamination in samples of lettuce (Lactuca sativa commercialized in Lavras city, Minas Gerais. The samples of lettuce showed low hygienic conditions, indicated by the presence of parasites of animal or human origin and high concentration of fecal coliforms.

Wild lettuce (Lactuca virosa) toxicity.

Science.gov (United States)

Besharat, Sima; Besharat, Mahsa; Jabbari, Ali

2009-01-01

Wild lettuce (Lactuca virosa) can cause toxic effects when eaten. Wild lettuce grows in the north of Iran and some natives consume it unaware of its adverse side effects. We describe eight patients with manifestations of wild lettuce toxicity, admitted to a general hospital affiliated to the Golestan University of Medical Sciences. All the patients recovered (although one had to spend 48 h in the intensive care unit) and no chronic complications were reported. A clinical suspicion of toxicity caused by wild lettuce intake and an accurate history formed the basis of the diagnosis. Conservative treatment, vital sign monitoring, control of patient intake and output, and reducing patient agitation provided the basis for treatment.

Potential of macroalgae for biodiesel production: Screening and evaluation studies.

Science.gov (United States)

Abomohra, Abd El-Fatah; El-Naggar, Amal Hamed; Baeshen, Areej Ali

2018-02-01

Nowadays, biofuel production is a fast expanding industry and is facing a growing dilemma about a feedstock source capable of keeping up with demand. Recently, macroalgae have been attracting a wide attention as a source for biofuel. In the present study, ten macroalgae were collected and screened as biodiesel feedstocks. As a result of their high biomass production and relatively high lipid content, Ulva lactuca, Padina boryana and Ulva intestinalis showed the highest significant lipids and fatty acid methyl esters (FAMEs) areal productivities among the studied species. Saturated fatty acids (SAFs) showed insignificant differences in the selected species, with noticeably significant higher polyunsaturated fatty acids (PUFAs) content in U. lactuca by 4.2 and 3 times, with respect to P. boryana and U. intestinalis, respectively. The recorded increase in PUFAs was attributed to higher content of C16:4n-3, C18:3n-3 and C18:4n-3. By lipid fractionation, P. boryana showed significant higher concentration of neutral lipids (37.7 mg g -1 CDW, representing 46.7% of total fatty acids) in comparison to U. lactuca and U. intestinalis, which showed 16% and 17% lower neutral lipid fractions, respectively. In addition, biodiesel characteristics of the studied macroalgae complied with that of international standards. Furthermore, oil-free residual biomass can be readily converted into fermentable sugars or biogas due to its high carbohydrates content, which adds to the economics of macroalgae as biofuel feedstock. In conclusion, the present study confirmed that macroalgae represent an attractive alternative renewable feedstock for biodiesel and other biofuels. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Zooming in on the lettuce genome: species relationships in Lactuca s.l., inferred from chromosomal and molecular characters

OpenAIRE

Koopman, W.J.M.

2002-01-01

Lactuca sativa (cultivated lettuce) is the world's most important leafy salad vegetable. Apart from L. sativa , the genus Lactuca contains ca. 75 wild species, potentially useful to improve, for example, taste, texture, and disease resistance of cultivated lettuce. The wild species L. serriola (Prickly Lettuce), L. saligna (Least Lettuce), and L. virosa (Great...

Plant Age Affects Wound-Induced Senescense in Lactuca Sativa L

NARCIS (Netherlands)

Witkowska, I.M.; Woltering, E.J.

2014-01-01

In the present study we investigated the performance of dark-stored wounded leaf discs and pieces (to some extent mimicking fresh-cut product) of Lactuca sativa L. in relation to the physiological maturity at harvest. We used two related genotypes, i.e. a green (cv. Troubadour) and a red butterhead

Green tide to green fuels: TG–FTIR analysis and kinetic study of Ulva prolifera pyrolysis

International Nuclear Information System (INIS)

Ceylan, Selim; Goldfarb, Jillian L.

2015-01-01

Highlights: • Distributed Activation Energy Model applied to Ulva prolifera pyrolysis. • Model and experimental data in good agreement to predict activation energy. • Ulva prolifera shows relatively low activation energy compared to other macroalgae. • Evolved gas analysis shows CO 2 emission decreasing with temperature. • Methane evolution increases with temperature, peaks at 800 °C. - Abstract: The world grapples with identifying renewable replacements for fossil fuels. Ulva prolifera, a macroalgae species that has caused green tides in China and Europe, represents a possible source of renewable energy. Given its low lipid content, thermochemical conversion techniques such as pyrolysis may be more suitable than biochemical techniques. We apply the Distributed Activation Energy Model to determine the activation energy of pyrolysis of U. prolifera from thermogravimetric data with combined evolved gas analysis via FTIR. Correlation coefficients for the DAEM were greater than 0.98 at each conversion; the apparent activation energy ranged from 130 to 152 kJ/mol, in good accord with the literature. Three stages of decomposition were noted over the entire temperature range; below 110 °C mass loss due to moisture removal. The largest stage of pyrolysis occurred between 190 and 400 °C with peak mass loss conversion rates up to 8.1 wt% per minute at 20 °C/min. The concentration of CO 2 in the evolved gas peaked along with mass loss rate at 242.7 °C. Stage III of pyrolysis saw a slow mass loss rate and a significant amount of methane from the macroalgae. Given its low energy, nutrient, land and maintenance requirements to grow, tolerance to a variety of environmental conditions, and low pyrolysis activation energies (as compared to other macroalgae), thermochemical conversion via pyrolysis is a viable way to extract energy from this seaweed species

Root constituents of Lactuca sibirica and a comparison of metabolite profiles of L. sibirica and L. tatarica

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Wanda Kisiel

2011-01-01

Full Text Available Nine known sesquiterpene lactones, including four lactucin-type guaianolides, four costuslactone-type guaianolides and one germacranolide, were isolated from roots of Lactuca sibirica (Asteraceae, six of which were glycoside derivatives. The chemosystematic significance of the compounds is discussed in the context of sesquiterpenoids present in roots of the closely related species Lactuca tatarica. A comparison of sesquiterpene lactone profiles indicate that the species can be differentiated on the basis of their germacranolide glycoside compositions.

Reduction of nitrogen in the excretion on Japanese flounder using Ulva and Capitellid; Anaaosa to itogokai ni yoru hirame haisetsubutsuchu no chisso shori

Energy Technology Data Exchange (ETDEWEB)

Honda, H.; Kikuchi, K.; Sakaguchi, I. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1997-03-01

To develop the culture residue treatment technique using aquatic organisms, the ammonia and nitrate uptake rates of seaweed Ulva and the nitrogen reduction rate of polychaeta annelid Captella sp. with organic sediment predaceous ability were examined in the excretion of Japanese flounder. Nitrogen uptake rate of Ulva was affected by water temperature. It was highest at 20degC, followed at 15degC and 25degC in the order. It was not affected by light intensity between 1500 and 6000 lux. Ammonia and nitrate uptake rates by Ulva were estimated to be 28.2 and 14.6 {mu}g-N/g/h at 20degC under 3000 lux, respectively. Proportion of feces excreted from Capitellid to ingested sediments was 0.38. At 25degC, Capitellid population of one thousand individuals ingested-N at the rate of 24 mg-N/day, and excreted the feces-N of Capitellid at the rate of 7 mg-N/day. About 70% of nitrogen in the sediment was reduced through this process. 15 refs., 9 figs., 13 tabs.

True identity of the European freshwater Ulva (Chlorophyta, Ulvophyceae) revealed by a combined molecular and morphological approach

Czech Academy of Sciences Publication Activity Database

Mareš, Jan; Leskinen, E.; Sitkowska, M.; Skácelová, O.; Blomster, J.

2011-01-01

Roč. 47, č. 5 (2011), 1177-1192 ISSN 0022-3646 R&D Projects: GA ČR GA206/09/0697 Institutional research plan: CEZ:AV0Z60050516 Keywords : green algae * taxonomy * Ulva Subject RIV: EF - Botanics Impact factor: 2.071, year: 2011

Uptake of perfluorinated alkyl acids by hydroponically grown lettuce (Lactuca sativa)

NARCIS (Netherlands)

Felizeter, S.; McLachlan, M.; de Voogt, P.

2012-01-01

An uptake study was carried out to assess the potential human exposure to perfluorinated alkyl acids (PFAAs) through the ingestion of vegetables. Lettuce (Lactuca sativa) was grown in PFAA-spiked nutrient solutions at four different concentrations, ranging from 10 ng/L to 10 μg/L. Eleven

Aspectos ecologicos de las algas marinas de la provincia de Concepcion, Chile

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Krisler Alveal

1980-12-01

Full Text Available Studies carried out in various localities of the Province of Concepción, Chile (36º40'S; 70º06'W estabilished the existence of two principal patterns of zonation defined by the populations of Mastocarpus sp. (¿ ?, Tridaea laminarioides, Gelidium pussilum, Ulva lactuca and Perumytilus purpuratus which occupy the lower hydrolittoral. In submerged levels the populations of Gracilaria and Macrocystis. form growths of moderate dimensions and in shallow waters, Iridaea ciliata, Gymnogongrus furcellatus and Gigartina chamissoii in scatterd patches.

FACTORES QUE INCIDEN EN LA LIBERACIÓN DE ZOOSPORAS DE Spongospora subterranea (Wallroth Lagerheim f. sp. subterranea Tomlinson FACTORS AFECTING THE ZOOSPORE RELEASE OF Spongospora subterranean (Wallroth Lagerheim f. sp. subterranea Tomlinson

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Daniel Esteban Alzate Velez

2008-12-01

Full Text Available Spongospora subterranea (Wallroth Lagerheim f. sp. subterranea Tomlinson es el agente causal de la sarna polvosa de la papa. Este patógeno es un protozoario, su infección ocurre por medio de zoosporas las cuales se liberan a partir de quistosoros y son el principal modo de dispersión de la enfermedad. Estos pueden encontrarse en tubérculos, raíces y el suelo, donde permanecen como estructuras de resistencia por varios años, hasta cuando las condiciones ambientales favorecen la liberación de zoosporas, para dar inicio a nuevas infecciones. En este trabajo, se evaluó el efecto de los exudados de raíz de papa, temperatura y fuente de inóculo con quistosoros aislados de suelo, raíz y tubérculo con el objetivo de verificar las condiciones en las cuales ocurre la liberación de zoosporas. Para tal fin se realizaron dos experimentos, en el primero se evaluó el efecto del agua y extracto de raíces y en el segundo el extracto de raíces y las diferentes fuentes de inóculo. Las evaluaciones se hicieron por conteo de zoosporas móviles durante 120 horas cada 24 horas. Se observó que el exudado de raíz tiene una alta influencia en la liberación de zoosporas, la cual ocurre entre los 15 y 23 °C a partir de las 48 y hasta las 96 horas, no se detectaron diferencias entre las fuentes de inóculo, lo que indica que independiente de su origen, si existen las condiciones ambientales adecuadas los quistosoros, tienen la capacidad de liberar un número suficiente de zoosporas que potencialmente pueden iniciar el proceso de infección en el hospedero.Spongospora subterranea (Wallroth Lagerheim f. sp. subterranea Tomlinson is the causal agent of potato powdery scab. This pathogen is worldwide distributed on the potato fields, infections occurs by zoospores which are inside resting spores called sporeballs or cystosori which are the principal way of disease spread. Sporeballs can be found on tubers, roots and soil as resistance structure, that can

Effect of arabinogalactan proteins from the root caps of pea and Brassica napus on Aphanomyces euteiches zoospore chemotaxis and germination.

Science.gov (United States)

Cannesan, Marc Antoine; Durand, Caroline; Burel, Carole; Gangneux, Christophe; Lerouge, Patrice; Ishii, Tadashi; Laval, Karine; Follet-Gueye, Marie-Laure; Driouich, Azeddine; Vicré-Gibouin, Maïté

2012-08-01

Root tips of many plant species release a number of border, or border-like, cells that are thought to play a major role in the protection of root meristem. However, little is currently known on the structure and function of the cell wall components of such root cells. Here, we investigate the sugar composition of the cell wall of the root cap in two species: pea (Pisum sativum), which makes border cells, and Brassica napus, which makes border-like cells. We find that the cell walls are highly enriched in arabinose and galactose, two major residues of arabinogalactan proteins. We confirm the presence of arabinogalactan protein epitopes on root cap cell walls using immunofluorescence microscopy. We then focused on these proteoglycans by analyzing their carbohydrate moieties, linkages, and electrophoretic characteristics. The data reveal (1) significant structural differences between B. napus and pea root cap arabinogalactan proteins and (2) a cross-link between these proteoglycans and pectic polysaccharides. Finally, we assessed the impact of root cap arabinogalactan proteins on the behavior of zoospores of Aphanomyces euteiches, an oomycetous pathogen of pea roots. We find that although the arabinogalactan proteins of both species induce encystment and prevent germination, the effects of both species are similar. However, the arabinogalactan protein fraction from pea attracts zoospores far more effectively than that from B. napus. This suggests that root arabinogalactan proteins are involved in the control of early infection of roots and highlights a novel role for these proteoglycans in root-microbe interactions.

Optimization study on the hydrogen peroxide pretreatment and production of bioethanol from seaweed Ulva prolifera biomass.

Science.gov (United States)

Li, Yinping; Cui, Jiefen; Zhang, Gaoli; Liu, Zhengkun; Guan, Huashi; Hwang, Hueymin; Aker, Winfred G; Wang, Peng

2016-08-01

The seaweed Ulva prolifera, distributed in inter-tidal zones worldwide, contains a large percentage of cellulosic materials. The technical feasibility of using U. prolifera residue (UPR) obtained after extraction of polysaccharides as a renewable energy resource was investigated. An environment-friendly and economical pretreatment process was conducted using hydrogen peroxide. The hydrogen peroxide pretreatment improved the efficiency of enzymatic hydrolysis. The resulting yield of reducing sugar reached a maximum of 0.42g/g UPR under the optimal pretreatment condition (hydrogen peroxide 0.2%, 50°C, pH 4.0, 12h). The rate of conversion of reducing sugar in the concentrated hydrolysates to bioethanol reached 31.4% by Saccharomyces cerevisiae fermentation, which corresponds to 61.7% of the theoretical maximum yield. Compared with other reported traditional processes on Ulva biomass, the reducing sugar and bioethanol yield are substantially higher. Thus, hydrogen peroxide pretreatment is an effective enhancement of the process of bioethanol production from the seaweed U. prolifera. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of different algae in diet on growth and interleukin (IL-10 production of juvenile sea cucumber Apostichopus japonicus

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Md Anisuzzaman

2017-10-01

Full Text Available Abstract The experiment was conducted to investigate the effects of different algae in diet on growth, survival, and interleukin-10 productions of sea cucumber. At first, a 9-week feeding trail was conducted to evaluate the growth performance and survival of the sea cucumber fed one of the six experimental diets containing ST (Sargassum thunbergii, UL (Ulva lactuca, UP (Undaria pinnatifida, LJ (Laminaria japonica, SS (Schizochytrium sp., and NO (Nannochloropsis oculata in a recirculating aquaculture system. The result showed that survival was not significantly different among the dietary treatments, and the specific growth rate (SGR of sea cucumber fed the UL diet (1.58% d−1 was significantly higher than that of sea cucumber fed the other diets (P < 0.05, except for the LJ and NO diets. Secondly, interleukin (IL-10 gene expression was determined where mice splenocytes were stimulated with 10 μg ml−1 of sea cucumber extracts for 2 h. The result showed that IL-10 gene expression levels were significantly increased in UL, LJ, and NO diets fed sea cucumber extracts compared to other experimental diets. The results suggest that dietary inclusion with Ulva lactuca, Laminaria japonica, and Nannochloropsis oculata algae may improve the growth of juvenile sea cucumber and could upregulate IL-10 gene expression in mice splenocytes. Such detailed information could be helpful in further development of more appropriate diets for sea cucumber culture.

Culture and hybridization experiments on an ulva clade including the Qingdao strain blooming in the yellow sea.

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Masanori Hiraoka

2011-05-01

Full Text Available In the summer of 2008, immediately prior to the Beijing Olympics, a massive green tide of the genus Ulva covered the Qingdao coast of the Yellow Sea in China. Based on molecular analyses using the nuclear encoded rDNA internal transcribed spacer (ITS region, the Qingdao strains dominating the green tide were reported to be included in a single phylogenetic clade, currently regarded as a single species. On the other hand, our detailed phylogenetic analyses of the clade, using a higher resolution DNA marker, suggested that two genetically separate entities could be included within the clade. However, speciation within the Ulva clade has not yet been examined. We examined the occurrence of an intricate speciation within the clade, including the Qingdao strains, via combined studies of culture, hybridization and phylogenetic analysis. The two entities separated by our phylogenetic analyses of the clade were simply distinguished as U. linza and U. prolifera morphologically by the absence or presence of branches in cultured thalli. The inclusion of sexual strains and several asexual strains were found in each taxon. Hybridizations among the sexual strains also supported the separation by a partial gamete incompatibility. The sexually reproducing Qingdao strains crossed with U. prolifera without any reproductive boundary, but a complete reproductive isolation to U. linza occurred by gamete incompatibility. The results demonstrate that the U. prolifera group includes two types of sexual strains distinguishable by crossing affinity to U. linza. Species identification within the Ulva clade requires high resolution DNA markers and/or hybridization experiments and is not possible by reliance on the ITS markers alone.

Culture and Hybridization Experiments on an Ulva Clade Including the Qingdao Strain Blooming in the Yellow Sea

Science.gov (United States)

Hiraoka, Masanori; Ichihara, Kensuke; Zhu, Wenrong; Ma, Jiahai; Shimada, Satoshi

2011-01-01

In the summer of 2008, immediately prior to the Beijing Olympics, a massive green tide of the genus Ulva covered the Qingdao coast of the Yellow Sea in China. Based on molecular analyses using the nuclear encoded rDNA internal transcribed spacer (ITS) region, the Qingdao strains dominating the green tide were reported to be included in a single phylogenetic clade, currently regarded as a single species. On the other hand, our detailed phylogenetic analyses of the clade, using a higher resolution DNA marker, suggested that two genetically separate entities could be included within the clade. However, speciation within the Ulva clade has not yet been examined. We examined the occurrence of an intricate speciation within the clade, including the Qingdao strains, via combined studies of culture, hybridization and phylogenetic analysis. The two entities separated by our phylogenetic analyses of the clade were simply distinguished as U. linza and U. prolifera morphologically by the absence or presence of branches in cultured thalli. The inclusion of sexual strains and several asexual strains were found in each taxon. Hybridizations among the sexual strains also supported the separation by a partial gamete incompatibility. The sexually reproducing Qingdao strains crossed with U. prolifera without any reproductive boundary, but a complete reproductive isolation to U. linza occurred by gamete incompatibility. The results demonstrate that the U. prolifera group includes two types of sexual strains distinguishable by crossing affinity to U. linza. Species identification within the Ulva clade requires high resolution DNA markers and/or hybridization experiments and is not possible by reliance on the ITS markers alone. PMID:21573216

Time Course Exo-Metabolomic Profiling in the Green Marine Macroalga Ulva (Chlorophyta for Identification of Growth Phase-Dependent Biomarkers

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Taghreed Alsufyani

2017-01-01

Full Text Available The marine green macroalga Ulva (Chlorophyta lives in a mutualistic symbiosis with bacteria that influence growth, development, and morphogenesis. We surveyed changes in Ulva’s chemosphere, which was defined as a space where organisms interact with each other via compounds, such as infochemicals, nutrients, morphogens, and defense compounds. Thereby, Ulva mutabilis cooperates with bacteria, in particular, Roseovarius sp. strain MS2 and Maribacter sp. strain MS6 (formerly identified as Roseobacter sp. strain MS2 and Cytophaga sp. strain MS6. Without this accompanying microbial flora, U. mutabilis forms only callus-like colonies. However, upon addition of the two bacteria species, in effect forming a tripartite community, morphogenesis can be completely restored. Under this strictly standardized condition, bioactive and eco-physiologically-relevant marine natural products can be discovered. Solid phase extracted waterborne metabolites were analyzed using a metabolomics platform, facilitating gas chromatography-mass spectrometry (GC-MS and liquid chromatography-mass spectrometry (LC-MS analysis, combined with the necessary acquisition of biological metadata. Multivariate statistics of the GC-MS and LC-MS data revealed strong differences between Ulva’s growth phases, as well as between the axenic Ulva cultures and the tripartite community. Waterborne biomarkers, including glycerol, were identified as potential indicators for algal carbon source and bacterial-algal interactions. Furthermore, it was demonstrated that U. mutabilis releases glycerol that can be utilized for growth by Roseovarius sp. MS2.

Anaerobic co-digestion of Tunisian green macroalgae Ulva rigida with sugar industry wastewater for biogas and methane production enhancement.

Science.gov (United States)

Karray, Raida; Karray, Fatma; Loukil, Slim; Mhiri, Najla; Sayadi, Sami

2017-03-01

Ulva rigida is a green macroalgae, abundantly available in the Mediterranean which offers a promising source for the production of valuable biomaterials, including methane. In this study, anaerobic digestion assays in a batch mode was performed to investigate the effects of various inocula as a mixture of fresh algae, bacteria, fungi and sediment collected from the coast of Sfax, on biogas production from Ulva rigida. The results revealed that the best inoculum to produce biogas and feed an anaerobic reactor is obtained through mixing decomposed macroalgae with anaerobic sludge and water, yielding into 408mL of biogas. The process was then investigated in a sequencing batch reactor (SBR) which led to an overall biogas production of 375mL with 40% of methane. Further co-digestion studies were performed in an anaerobic up-flow bioreactor using sugar wastewater as a co-substrate. A high biogas production yield of 114mL g -1 VS added was obtained with 75% of methane. The co-digestion proposed in this work allowed the recovery of natural methane, providing a promising alternative to conventional anaerobic microbial fermentation using Tunisian green macroalgae. Finally, in order to identify the microbial diversity present in the reactor during anaerobic digestion of Ulva rigida, the prokaryotic diversity was investigated in this bioreactor by the denaturing gradient gel electrophoresis (DGGE) method targeting the 16S rRNA gene. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of antibacterial activity of some selected green seaweed extracts from Muttam coastal areas, Kanyakumari, Tamil Nadu, India

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Pushparaj Arunachalam

2014-02-01

Full Text Available Objective: To investigate the antimicrobial activity of the selected marine green algae Ulva lactuca (U. lactuca, Cheatomorpha linoides and Helimeda macroloba against six strains of Gram-positive bacteria [Staphylococcus aureus (S. aureus, Bacillus subtilis and Lactobacillus acidophilus (L. acidophilus] and Gram-negative bacteria [Escherichia coli, Pseudomonas aeruginosa (P. aeruginosa and Proteus mirabilis]. Methods: The selected green seaweed extracts were experimented with four different solvents (acetone, ethanol, methanol and chloroform against the selected pathogens by using agar disc diffusion method. Results: The maximum activity (7 mm was observed by the extract of U. lactuca against Proteus mirabilis by using methanol as a solvent and the lowest activity (2 mm was recorded by the extract of U. lactuca against L. acidophilus by using chloroform as a solvent and ethanol extract against P. aeruginosa. The lowest activity (2 mm was seen in the extract of Cheatomorpha linoides by using ethanol and methanol as a solvent against S. aureus. In Helimeda macroloba extract, the lowest activity was recorded against Escherichia coli by using chloroform as a solvent. The microbial strains S. aureus, P. aeruginosa, Bacillus subtilis and L. acidophilus were resistant to the chloroform and methanol of all selected seaweeds. Conclusions: Further study should be needed to identify the prime compound which is responsible for the activity against the selected pathogens especially those causing the human diseases.

Mercury in marine organisms of the Tay region

Energy Technology Data Exchange (ETDEWEB)

Jones, A M; Jones, Y; Stewart, W D.P.

1972-07-21

The problem of mercury pollution in the Tay region of the United Kingdom is discussed with emphasis on mercury concentration within marine algae and invertebrates. High levels of Hg were found in Broughty Ferry algae while there was no detectable mercury in any of the samples collected from north of Arbroath. Most was found in the thallose algae, Ulva lactuca and Porphyra umbilicalis, and in Ceramium rubrum. In studies carried out on molluscs, high levels were found in the lamellibranch, Mytilus edulis and in the gastropods Littorina littoralis and Nucella lapillus. 12 references, 3 tables.

Heavy metal determinations in algae and clams and their possible employment for assessing the sea water quality criteria.

Science.gov (United States)

Locatelli, C; Fabbri, D; Torsi, G

2001-01-01

An empirical criterion for a possible classification of sea water quality is proposed. It is based on the knowledge of metal content in algae (Ulva Rigida) and clams (Tapes Philippinarum), two species present in marine ecosystems. The elements considered are Hg, Cu, Pb, Cd, Zn. The analytical technique employed is Differential Pulse Anodic Stripping Voltammetry (DPASV) in the case of Cu, Pb, Cd, Zn, while the determination of mercury is obtained by the Cold Vapour Atomic Absorption Spectroscopy (CV-AAS) technique with SnCl2 as reducing agent. The analytical procedure has been verified on three standard reference materials: Sea Water BCR-CRM 403, Ulva Lactuca BCR-CRM 279 and Mussel Tissue BCR-CRM 278. For all the elements, in addition to detection limits, accuracy and precision are given: the former, expressed as relative error (e), and the latter, expressed as relative standard deviation (Sr), were in all cases lower than 6%.

Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines

NARCIS (Netherlands)

Broeke, ten C.J.M.; Dicke, M.; Loon, van J.J.A.

2013-01-01

The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains

Acinetobacter lactucae sp. nov., isolated from iceberg lettuce (Asteraceae: Lactuca sativa).

Science.gov (United States)

Rooney, Alejandro P; Dunlap, Christopher A; Flor-Weiler, Lina B

2016-09-01

Strain NRRL B-41902T and three closely related strains were isolated from iceberg lettuce. The strain was found to consist of strictly aerobic, Gram-stain-negative rods that formed cocci in late stationary phase. 16S rRNA gene sequence analysis showed that strain NRRL B-41902T was most closely related to species within the genera Acinetobacter, and that a grouping of it and the three other closely related strains was most closely related to the type strain of Acinetobacter pittii, which was also confirmed through a phylogenomic analysis. Moreover, in silico DNA-DNA hybridization analysis revealed a substantial amount of genomic divergence (39.1 %) between strain NRRL B-41902T and the type strain of A. pittii, which is expected if the strains represent distinct species. Further phenotypic analysis revealed that strain NRRL B-41902T was able to utilize a combination of l-serine, citraconic acid and citramalic acid, which differentiated it from other, closely related Acinetobacter species. Therefore, strain NRRL B-41902T (=CCUG 68785T) is proposed as the type strain of a novel species, Acinetobacter lactucae sp. nov.

Radionuclides in marine macroalgae from Amchitka and Kiska Islands in the Aleutians: establishing a baseline for future biomonitoring

International Nuclear Information System (INIS)

Burger, Joanna; Gochfeld, Michael; Kosson, David S.; Powers, Charles W.; Jewett, Stephen; Friedlander, Barry; Chenelot, Heloise; Volz, Conrad D.; Jeitner, Christian

2006-01-01

Levels of radionuclides in seven species of marine brown algae and Ulva were determined to establish a baseline for the Northern Pacific Ocean/Bering Sea (Aleutian Islands). There were differences in levels among algal species and locations (Amchitka Island vs Kiska Island). No values were above the minimum detectable activity (MDA) level for 137 Cs, 129 I, 6 Co, 152 Eu, 9 Sr, and 99 Tc. There were interspecific differences in some radionuclides: Ulva lactuca (=Ulva fenestrata) had the highest levels of 241 Am, Alaria fistulosa had the highest levels of 239,24 Pu, and Fucus distichus (=Fucus gardneri) had the highest levels of 234 U, 235 U, and 238 U. However, levels of all radionuclides were generally low and near the MDA for all isotopes. Although Amchitka Island had higher levels of 239,24 Pu than Kiska, the differences were very small and not significant biologically. The data indicate that algae can be useful bioindicators of actinides because they accumulate them at very low environmental levels, allowing them to provide early warning of any potential seepage of radionuclides into the marine environment. Further, the data indicate that some species (the intertidal Fucus) are better accumulators than others, and these should be used as bioindicators in future monitoring schemes

Species relationships in Lactuca S.L. (Lactuceae, Asteraceae) inferred from AFLP fingerprints

NARCIS (Netherlands)

Koopman, W.J.M.; Zevenbergen, M.J.; Berg, van den R.G.

2001-01-01

An AFLP data set comprising 95 accessions from 20 species of Lactuca s.l. (sensu lato) and related genera was generated using the primer combinations E35/M48 and E35/M49. In phenetic analyses of a data subset, clustering with UPGMA based on Jaccard's similarity coefficient resulted in the highest

Deoxy-liquefaction of three different species of macroalgae to high-quality liquid oil.

Science.gov (United States)

Li, Jinhua; Wang, Guoming; Chen, Ming; Li, Jiedong; Yang, Yaoyao; Zhu, Qiuyan; Jiang, Xiaohuan; Wang, Zonghua; Liu, Haichao

2014-10-01

Three species of macroalgae (Ulva lactuca, Laminaria japonica and Gelidium amansii) were converted into liquid oils via deoxy-liquefaction. The elemental analysis, FTIR and GC-MS results showed that the three liquid oils were all mainly composed of aromatics, phenols, alkanes and alkenes, other oxygen-containing compounds, and some nitrogen-containing compounds though there were some differences in terms of their types or contents due to the different constituents in the macroalgae feedstocks. The oxygen content was only 5.15-7.30% and the H/C molar ratio was up to 1.57-1.73. Accordingly, the HHV of the three oils were 42.50, 41.76 and 40.00 MJ/kg, respectively. The results suggested that U. lactuca, L. japonica and G. amansii have potential as biomass feedstock for fuel and chemicals and that deoxy-liquefaction technique may be an effective way to convert macroalgae into high-quality liquid oil. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chlorophyta and Rhodophyta macroalgae: a source of health promoting phytochemicals.

Science.gov (United States)

Santos, Sonia A O; Vilela, Carla; Freire, Carmen S R; Abreu, Maria H; Rocha, Silvia M; Silvestre, Armando J D

2015-09-15

A detailed study of the lipophilic composition of Codium tomentosum, Ulva lactuca, Gracilaria vermiculophylla and Chondrus crispus macroalgae cultivated in the Portuguese coast was carried out by gas chromatography-mass spectrometry before and after alkaline hydrolysis. Their long-chain aliphatic alcohols and monoglycerides compositions are reported for the first time. Additionally, other new compounds were also identified: phytol and neophytadiene in C. tomentosum, U. lactuca and G. vermiculophylla and stigmasterol, α-tocopherol and 24-methylenecholesterol in C. tomentosum. The lipophilic fraction of the studied macroalgae are mainly constituted by fatty acids (110.1-1030.5mgkg(-1) of dry material) and sterols (14.8-1309.1mgkg(-1) of dry material). C. tomentosum showed to be a valuable source of stigmasterol (1229.0mgkg(-1) of dry material) and α-tocopherol (21.8mgkg(-1) of dry material). These results are a relevant contribution for the valorisation of these macroalgae species as sources of valuable phytochemicals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Salinity critical threshold values for photosynthesis of two cosmopolitan seaweed species: providing baselines for potential shifts on seaweed assemblages.

Science.gov (United States)

Scherner, Fernando; Ventura, Robson; Barufi, José Bonomi; Horta, Paulo Antunes

2013-10-01

Climate change has increased precipitation in several South American regions leading to higher freshwater inputs into marine systems with potential to cause salinity declines along the coast. The current salinity profile on the southern coast of Brazil was surveyed during four years providing a baseline of the current salinity pattern in the region. Additionally, the effects of salinity decreases on the photosynthesis of the seaweeds Ulva lactuca and Sargassum stenophyllum were investigated in laboratory. Seaweeds were cultured at salinities 5, 15 and 34 and at the mean winter and summer temperatures. Photosynthetic performance was measured following 24 and 96 h from the beginning of experiment. U. lactuca remained practically unaltered by low salinities while S. stenophyllum presented declines of important photosynthetic parameters. This is due to the different regulation abilities of energy distribution at the PSII of the two species. These differences have potential to lead to seaweed community shifts. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preliminary results on laboratory simulations of the decomposition of the green algae Ulva rigida

International Nuclear Information System (INIS)

Karavoltsos, S.; Scoullous, M.; Kaberi, H.

1999-01-01

The Ulva Rigida is a cosmopolitan green algae characteristic of many eutrophic and mesotrophic coastal environments. The effect of its growth and decomposition on the cycle of trace metals has been studied by using enclosures in the site Loutropyrgos over a number of years. The present study is a continuation of that research. Its main aim was to simulate a number of the field experiments in the laboratory, under more controlled conditions and understand better the impact of the decomposition of algae on sea water and sediment

Differential distribution of cadmium in lettuce (Lactuca sativa L.) and maize (Zea mays L.)

NARCIS (Netherlands)

Florijn, P.J.

1993-01-01

Large genotypic variation in shoot Cd concentrations has been reported in literature for several plant species including lettuce ( Lactuca sativa L.) and maize ( Zea mays L.). The objective of this thesis was to elucidate the physiological andlor

Effect of Arabinogalactan Proteins from the Root Caps of Pea and Brassica napus on Aphanomyces euteiches Zoospore Chemotaxis and Germination12[C][W

Science.gov (United States)

Cannesan, Marc Antoine; Durand, Caroline; Burel, Carole; Gangneux, Christophe; Lerouge, Patrice; Ishii, Tadashi; Laval, Karine; Follet-Gueye, Marie-Laure; Driouich, Azeddine; Vicré-Gibouin, Maïté

2012-01-01

Root tips of many plant species release a number of border, or border-like, cells that are thought to play a major role in the protection of root meristem. However, little is currently known on the structure and function of the cell wall components of such root cells. Here, we investigate the sugar composition of the cell wall of the root cap in two species: pea (Pisum sativum), which makes border cells, and Brassica napus, which makes border-like cells. We find that the cell walls are highly enriched in arabinose and galactose, two major residues of arabinogalactan proteins. We confirm the presence of arabinogalactan protein epitopes on root cap cell walls using immunofluorescence microscopy. We then focused on these proteoglycans by analyzing their carbohydrate moieties, linkages, and electrophoretic characteristics. The data reveal (1) significant structural differences between B. napus and pea root cap arabinogalactan proteins and (2) a cross-link between these proteoglycans and pectic polysaccharides. Finally, we assessed the impact of root cap arabinogalactan proteins on the behavior of zoospores of Aphanomyces euteiches, an oomycetous pathogen of pea roots. We find that although the arabinogalactan proteins of both species induce encystment and prevent germination, the effects of both species are similar. However, the arabinogalactan protein fraction from pea attracts zoospores far more effectively than that from B. napus. This suggests that root arabinogalactan proteins are involved in the control of early infection of roots and highlights a novel role for these proteoglycans in root-microbe interactions. PMID:22645070

Plant Age Affects Wound-Induced Senescense in Lactuca Sativa L

OpenAIRE

Witkowska, I.M.; Woltering, E.J.

2014-01-01

In the present study we investigated the performance of dark-stored wounded leaf discs and pieces (to some extent mimicking fresh-cut product) of Lactuca sativa L. in relation to the physiological maturity at harvest. We used two related genotypes, i.e. a green (cv. Troubadour) and a red butterhead (cv. Teodore) differing in their pigment levels. For both genotypes, senescence of the wounded (fresh-cut) tissue prepared from leaves of younger plants was significantly delayed compared to wounde...

Macro algae as substrate for biogas production

DEFF Research Database (Denmark)

Møller, Henrik; Sarker, Shiplu; Gautam, Dhan Prasad

Algae as a substrate for biogas is superior to other crops since it has a much higher yield of biomass per unit area and since algae grows in the seawater there will be no competition with food production on agricultural lands. So far, the progress in treating different groups of algae as a source...... of energy is promising. In this study 5 different algae types were tested for biogas potential and two algae were subsequent used for co-digestion with manure. Green seaweed, Ulva lactuca and brown seaweed Laminaria digitata was co-digested with cattle manure at mesophilic and thermophilic condition...

Energy from algae using microbial fuel cells

KAUST Repository

Velasquez-Orta, Sharon B.; Curtis, Tom P.; Logan, Bruce E.

2009-01-01

Bioelectricity production froma phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73±1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m2 (277 W/m3) using C. vulgaris, and 0.76 W/m2 (215 W/m3) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs. © 2009 Wiley Periodicals, Inc.

Energy from algae using microbial fuel cells

KAUST Repository

Velasquez-Orta, Sharon B.

2009-08-15

Bioelectricity production froma phytoplankton, Chlorella vulgaris, and a macrophyte, Ulva lactuca was examined in single chamber microbial fuel cells (MFCs). MFCs were fed with the two algae (as powders), obtaining differences in energy recovery, degradation efficiency, and power densities. C. vulgaris produced more energy generation per substrate mass (2.5 kWh/kg), but U. lactuca was degraded more completely over a batch cycle (73±1% COD). Maximum power densities obtained using either single cycle or multiple cycle methods were 0.98 W/m2 (277 W/m3) using C. vulgaris, and 0.76 W/m2 (215 W/m3) using U. lactuca. Polarization curves obtained using a common method of linear sweep voltammetry (LSV) overestimated maximum power densities at a scan rate of 1 mV/s. At 0.1 mV/s, however, the LSV polarization data was in better agreement with single- and multiple-cycle polarization curves. The fingerprints of microbial communities developed in reactors had only 11% similarity to inocula and clustered according to the type of bioprocess used. These results demonstrate that algae can in principle, be used as a renewable source of electricity production in MFCs. © 2009 Wiley Periodicals, Inc.

Properties of polysaccharides in several seaweeds from Atlantic Canada and their potential anti-influenza viral activities

Science.gov (United States)

Jiao, Guangling; Yu, Guangli; Wang, Wei; Zhao, Xiaoliang; Zhang, Junzeng; Ewart, Stephen H.

2012-06-01

To explore the polysaccharides from selected seaweeds of Atlantic Canada and to evaluate their potential anti-influenza virus activities, polysaccharides were isolated from several Atlantic Canadian seaweeds, including three red algae ( Polysiphonia lanosa, Furcellaria lumbricalis, and Palmaria palmata), two brown algae ( Ascophyllum nodosum and Fucus vesiculosus), and one green alga ( Ulva lactuca) by sequential extraction with cold water, hot water, and alkali solutions. These polysaccharides were analyzed for monosaccharide composition and other general chemical properties, and they were evaluated for anti-influenza virus activities. Total sugar contents in these polysaccharides ranged from 15.4% (in U. lactuca) to 91.4% (in F. lumbricalis); sulfation level was as high as 17.6% in a polysaccharide from U. lactuca, whereas it could not be detected in an alikali-extract from P. palmaria. For polysaccharides from red seaweeds, the main sugar units were sulfated galactans (agar or carrageenan) for P. lanosa, F. lumbricalis, and xylans for P. palmata. In brown seaweeds, the polysaccharides largely contained sulfated fucans, whereas the polysaccharides in green seaweed were mainly composed of heteroglycuronans. Screening for antiviral activity against influenza A/PR/8/34 (H1N1) virus revealed that brown algal polysaccharides were particularly effective. Seaweeds from Atlantic Canada are a good source of marine polysaccharides with potential antiviral properties.

ANALISIS TUMBUH SELADA (LACTUCA SATIVA L) PADA PERBEDAAN JENIS PUPUK ORGANIK CAIR ( Lettuce (Lactuca Sativa L) Growth Analysis At Different Type Of Liquid Organic Fertilizer)

OpenAIRE

Duaja, Made Deviani; Arzita, .; Redo, Yan

2012-01-01

The objectives of this research are to analysis the growth and yield of Lettuce (Lactuca sativa L) at different type of organic liquid fertilizers. The experiment has conducted at Agriculture Faculty Research Farm, Jambi University. Six treatments were arranged in Randomized Completed Block Design. The treatments are kinds of liquid organic fertilizers, they are P0 (none of liquid organic fertilizers), P1 (Golden Harvest liquid organic fertilizers), P2 (NASA liquid organic fertilizers), P3 (C...

[Analysis of the mineral elements of Lactuca sativa under the condition of different spectral components].

Science.gov (United States)

Chen, Xiao-Li; Guo, Wen-Zhong; Xue, Xu-Zhang; Wang, Li-Chun; Li, Liang; Chen, Fei

2013-08-01

Mineral elements absorption and content of Lactuca sativa under different spectral component conditions were studied by ICP-AES technology. The results showed that: (1) For Lactuca sativa, the average proportion for Ca : Mg : K : Na : P was 5.5 : 2.5 : 2.3 : 1.5 : 1.0, the average proportion for Fe : Mn : Zn : Cu : B was 25.9 : 5.9 : 2.8 : 1.1 : 1.0; (2) The absorptions for K, P, Ca, Mg and B are the largest under the LED treatment R/B = 1 : 2.75, red light from fluorescent lamps and LED can both promote the absorptions of Fe and Cu; (3)The LED treatments exhibiting relatively higher content of mineral elements are R/B = 1 : 2.75 and R/W = 1 : 1 while higher dry matter accumulations are R/B = 1 : 2.75 and B/W = 1 : 1.

Physiological and physico-chemical characterization of dietary fibre from the green seaweed Ulva fasciata Delile

OpenAIRE

Carvalho,AFU.; Portela,MCC.; Sousa,MB.; Martins,FS.; Rocha,FC.; Farias,DF.; Feitosa,JPA.

2009-01-01

This work aims to assess the potential of the green seaweed Ulva fasciata Delile as an alternative source of dietary fibre (DF). Total DF content was determined, some of its physico-chemical properties described and the physiological effects of U. fasciata meal on rats fed a hypercholesterolemic diet were investigated. U. fasciata may be considered a potential alternative source of DF with a total content of about 400 g.kg-1 (dry basis) and interesting physico-chemical properties: water reten...

Sporulation of Bremia lactucae affected by temperature, relative humidity, and wind in controlled conditions

NARCIS (Netherlands)

Su, H.; Bruggen, van A.H.C.; Subbarao, K.V.; Scherm, H.

2004-01-01

The effects of temperature (5 to 25degreesC), relative humidity (81 to 100%), wind speed (0 to 1.0 in s(-1)), and their interactions on sporulation of Bremia lactucae on lettuce cotyledons were investigated in controlled conditions. Sporulation was affected significantly (P <0.0001) by

Dendritic cells pulsed with Pythium insidiosum (1,3)(1,6)-β-glucan, Heat-inactivated zoospores and immunotherapy prime naïve T cells to Th1 differentiation in vitro.

Science.gov (United States)

Ledur, Pauline C; Tondolo, Juliana S M; Jesus, Francielli P K; Verdi, Camila M; Loreto, Érico S; Alves, Sydney H; Santurio, Janio M

2018-03-01

Pythiosis is a life-threatening disease caused by the fungus-like microorganism Pythium insidiosum that can lead to death if not treated. Since P. insidiosum has particular cell wall characteristics, pythiosis is difficult to treat, as it does not respond well to traditional antifungal drugs. In our study, we investigated a new immunotherapeutic approach with potential use in treatment and in the acquisition of immunity against pythiosis. Dendritic cells from both human and mouse, pulsed with P. insidiosum heat-inactivated zoospore, (1,3)(1,6)-β-glucan and the immunotherapeutic PitiumVac ® efficiently induced naïve T cell differentiation in a Th1 phenotype by the activation of specific Th1 cytokine production in vitro. Heat-inactivated zoospores showed the greatest Th1 response among the tested groups, with a significant increase in IL-6 and IFN-γ production in human cells. In mice cells, we also observed a Th17 pathway induction, with an increase on the IL-17A levels in lymphocytes cultured with β-glucan pulsed DCs. These results suggest a potential use of DCs pulsed with P. insidiosum antigens as a new therapeutic strategy in the treatment and acquisition of immunity against pythiosis. Copyright © 2017 Elsevier GmbH. All rights reserved.

Plastid transformation in lettuce (Lactuca sativa L.) by biolistic DNA delivery.

Science.gov (United States)

Ruhlman, Tracey A

2014-01-01

The interest in producing pharmaceutical proteins in a nontoxic plant host has led to the development of an approach to express such proteins in transplastomic lettuce (Lactuca sativa L.). A number of therapeutic proteins and vaccine antigen candidates have been stably integrated into the lettuce plastid genome using biolistic DNA delivery. High levels of accumulation and retention of biological activity suggest that lettuce may provide an ideal platform for the production of biopharmaceuticals.

Semi-high throughput screening for potential drought-tolerance in lettuce (Lactuca sativa) germplasm collections

Science.gov (United States)

This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of th...

Two new mountainous species of Lactuca (Cichorieae, Asteraceae from Iran, one presenting a new, possibly myrmecochorous achene variant

Directory of Open Access Journals (Sweden)

Norbert Kilian

2012-04-01

Full Text Available It is shown that the concept of the Iranian endemic Lactuca polyclada in the sense of both its original author Boissier and its current use actually admixes two entirely different species, as was first noted by Beauverd a hundred years ago but has been neglected by later workers. One is a putative relative of L. rosularis, the other was recognised by Beauverd as a member of the genus Cicerbita. The name L. polyclada Boiss. is lectotypified here, maintaining its use as established by Beauverd for the Cicerbita species. Both species are morphologically delimited and mature achenes of Cicerbita polyclada are illustrated for the first time. The putative relative of Lactuca rosularis, a rare local endemic of the summit area of Kuh e-Dena, which has remained without a valid name by now, is described as a new species, Lactuca denaensis N. Kilian & Djavadi, and illustrated. A third member of the Lactuca rosularis group, L. hazaranensis Djavadi & N. Kilian, discovered among a recent collection and apparently being a rare chasmophyte of the Hazaran mountain massif in the province of Kerman, Iran, is described as a species new to science, illustrated and delimited from the other two species. This new species has peculiar achenes representing a hitherto unknown variant: the body of the beaked achenes is divided into two segments by a transversal constriction in the distal third. The proximal segment contains the embryo, the distal segment is solid with a lipid-containing yellow tissue. The easily detachable pappus and the equally easily detachable beak potentially obstruct dispersal by wind. Since detachment of the beak also exposes the lipid-containing tissue of the distal segment, its potential as an elaiosome and myrmecochory as a possible mode of dispersal are discussed.

Transformation of lettuce (Lactuca sativa) mediated by Agrobacterium tumefaciens.

Science.gov (United States)

Michelmore, R; Marsh, E; Seely, S; Landry, B

1987-12-01

Lactuca sativa can be routinely transformed using Ti plasmids of Agrobacterium tumefaciens containing a chimeric kanamycin resistance gene (NOS.NPTII.NOS). Critical experimental variables were plant genotype, bacterial concentration, presence of a nurse culture and timing of transfers between tissue culture media. Transformation was confirmed by the ability to callus and root in the presence of kanamycin, nopaline production, and by hybridization in Southern blots. Transformation has been achieved with several Ti vectors. Several hundred transformed plants have been regenerated. Kanamycin resistance was inherited monogenically. Homozygotes can be selected by growing R2 seedlings on media containing G418.

Obcy gatunkowo pyłek i czynnik chemiczny w indukcji rozwoju zarodków haploidalnych u Lactuca sativa L.

OpenAIRE

Piosik, Łukasz

2014-01-01

Wydział Biologii Sałata siewna (Lactuca sativa) jest popularną oraz cenną z ekonomicznego punktu widzenia rośliną warzywną. Głównym celem tej pracy było opracowanie efektywnej metody haploidyzacji Lactuca sativa, która byłaby użyteczna dla hodowców sałaty siewnej. Krzyżowanie oddalone oraz chemiczną indukcję prowadzono w warunkach in vivo oraz in vitro. Pyłek wszystkich gatunków należących do Asteraceae, kiełkował na znamionach sałaty już 1h po zapyleniu. Rozwój haploidalnych prazarodk...

Accumulation and effects of metal mixtures in two seaweed species.

Science.gov (United States)

Jarvis, Tayler A; Bielmyer-Fraser, Gretchen K

2015-05-01

Metal pollution, due to various anthropogenic sources, may pose a threat to marine ecosystems. Metals can be introduced into food chains via bioaccumulation in primary producers, and may potentially lead to toxic effects. Macroalgae are used as food by a wide variety of organisms, and are therefore extremely important in aquatic systems. This study investigated the accumulation and effects of metals in two macroalgae species. The green seaweed, Ulva lactuca and the red seaweed, Agardhiella subulata were each concurrently exposed to five metals (Cu, Ni, Pb, Cd, and Zn) and U. lactuca was also exposed to each metal individually for 48 h. Metal accumulation in the seaweed was measured, and various photosynthetic parameters were assessed, using imaging pulse amplitude modulated (PAM) fluorometry. Increased metal accumulation occurred in both seaweed species after 48 h exposure to metal mixtures and each metal individually. The distribution of metals in both seaweed species changed with increasing metal exposure concentrations, resulting in higher proportions of Cu and Zn in the metal-exposed groups, as compared to respective controls. Further, U. lactuca accumulated higher concentrations of metals when exposed to each metal individually rather than in metal mixtures, suggesting interactions among metals for uptake and/or bioaccumulation. Significant impairment of photosynthetic parameters in U. lactuca was observed after exposure to 100 and 1000 μg/L metal mixtures, as well as 100 μg/L of either Cd or Cu. These results demonstrate metal bioaccumulation and toxic effects in important primary producers, and may have implications for higher trophic levels. Published by Elsevier Inc.

The effect of soil environment on germination and emergence of prickly lettuce (Lactuca serriola L.

Directory of Open Access Journals (Sweden)

Jan Kapeluszny

2012-12-01

Full Text Available In 2007 mature achenes of prickly lettuce (Lactuca serriola L. were collected from a winter wheat crop growing on loess-derived brown earth soil, from the side of a dirt road, and from a hybrid alfalfa crop growing on heavy rendzina soil. In March 2008 the germination ability of achenes and the length of roots and above-ground parts of L. serriola seedlings were determined. The experiment was set up as a completely randomized design in 6 replicates and it was done in dishes. The dishes were filled with loess-derived brown soil and podzolic soil derived from light loamy sand with different pH values of 4.5, 5.5 and 7.0 obtained using laboratory methods. The second experiment evaluated the effect of medium type and light conditions on the germination of Lactuca serriola achenes. The experimental design was the same as in the above described experiment. The study found that there were significantly more germinating seeds from the plants growing in the alfalfa crop and on the dirt roadside compared to the plants from the wheat crop. Emerging plants showed higher germination ability on loess-derived soil with a pH of 5.5 and 7.0 than on podzolic soil derived from sand with the same pH. Lactuca serriola prefers soils rich in calcium compounds, and developing segetal cenopopulations produce diaspores capable of germination, thereby the numbers of individuals can increase and the continuity of this species in crop fields can be maintained. Seeds germinated significantly better in the dark than under the conditions of 12-hour illumination.

Levels of essential and toxic elements in Porphyra columbina and Ulva sp. from San Jorge Gulf, Patagonia Argentina

International Nuclear Information System (INIS)

Perez, Adriana Angela; Farias, Silvia Sara; Strobl, Analia Mabel; Perez, Laura Beatriz; Lopez, Clara Magdalena; Pineiro, Adriana; Roses, Otmaro; Fajardo, Maria Angelica

2007-01-01

Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahia Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 μg g -1 dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 μg g -1 dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb

Levels of essential and toxic elements in Porphyra columbina and Ulva sp. from San Jorge Gulf, Patagonia Argentina

Energy Technology Data Exchange (ETDEWEB)

Perez, Adriana Angela [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Farias, Silvia Sara [Comision Nacional de Energia Atomica, Gerencia de Tecnologia y Medio Ambiente, Buenos Aires (Argentina); Strobl, Analia Mabel [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Perez, Laura Beatriz [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Lopez, Clara Magdalena [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Pineiro, Adriana [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Roses, Otmaro [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Fajardo, Maria Angelica [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina)]. E-mail: copipat@sinectis.com.ar

2007-04-15

Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahia Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 {mu}g g{sup -1} dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 {mu}g g{sup -1} dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb.

Comparative study on metal biosorption by two macroalgae in saline waters: single and ternary systems.

Science.gov (United States)

Figueira, Paula; Henriques, Bruno; Teixeira, Ana; Lopes, Cláudia B; Reis, Ana T; Monteiro, Rui J R; Duarte, A C; Pardal, M A; Pereira, E

2016-06-01

The biosorption capability of two marine macroalgae (green Ulva lactuca and brown Fucus vesiculosus) was evaluated in the removal of toxic metals (Hg, Cd and Pb) from saline waters, under realistic conditions. Results showed that, independently of the contamination scenario tested, both macroalgae have a remarkable capacity to biosorb Hg and Pb. In single-contaminant systems, by using only c.a. 500 mg of non-pre-treated algae biomass (size macroalgae exhibited a similar selectivity toward the target metals: Hg > Pb> > Cd, although Pb removal by U. lactuca was more inhibited than that achieved by F. vesiculosus. Under the experimental conditions used, none of the macroalgae was effective to remove Cd (maximum removal of 20 %). In all cases, the kinetics of biosorption was mathematically described with success. Globally, it became clear that the studied macroalgae may be part of simple, efficient, and cost-effective water treatment technologies. Nevertheless, Fucus vesiculosus has greater potential, since it always presented higher initial sorption rates and higher removal efficiencies.

Optimizing the conditions for the microwave-assisted direct liquefaction of Ulva prolifera for bio-oil production using response surface methodology

International Nuclear Information System (INIS)

Liu, Junhai; Zhuang, Yingbin; Li, Yan; Chen, Limei; Guo, Jingxue; Li, Demao; Ye, Naihao

2013-01-01

Microwave-assisted direct liquefaction (MADL) of Ulva prolifera was performed in ethylene glycol (EG) using sulfuric acid (H 2 SO 4 ) as a catalyst. Response Surface Methodology (RSM) based on central composite rotatable design (CCRD) was employed to optimize the conditions of three independent variables (catalyst content, solvent-to-feedstock ratio and temperature) for the liquefaction yield. And the bio-oil was analyzed by elementary analysis, Fourier transform infrared spectroscopic analysis (FT-IR) and gas chromatography–mass spectrometry (GC–MS). The maximum liquefaction yield was 93.17%, which was obtained under a microwave power of 600 W for 30 min at 165 °C with a solvent-to-feedstock ratio of 18.87:1 and 4.93% sulfuric acid. The bio-oil was mainly composed of phthalic acid esters, alkenes and a fatty acid methyl ester with a long chain from C 16 to C 20 . - Highlights: • Ulva prolifera was converted to bio-oil through microwave-assisted direct liquefaction. • Response surface methodology was used to optimize the liquefaction technology. • A maximum liquefaction rate of 93.17 wt% bio-oil was obtained. • The bio-oil was composed of carboxylic acids and esters

Effect of low dose irradiation of 60Co γ-rays on seed germination, seedling growth and enzymes activity of Lactuca sativa

International Nuclear Information System (INIS)

Liu Xiuqing; Zhang Tie

2012-01-01

The seeds of Lactuca sativa were irradiated by different doses (10, 20, 30, 40, 50 Gy) of 60 Co γ-rays. The effects of low dose irradiation on seed germination, seedling growth and enzymes activity were investigated. The results indicated that low dose irradiation could promote germination rate, germinating viability, germination rate in the field, root length and height of seedling. The suitable dosage for low dose irradiation for Lactuca sativa was 30 Gy. POD activity after irradiation treatment in the range of 10 to 50 Gy and CAT activity after irradiation treatment in the range of 20 Gy to 40 Gy was lower than that of control. (authors)

DEVELOPMENTAL CHANGES IN THE GERMINATION, GROWTH AND CHLOROPHYLLASE ACTIVITY OF VIGNA MUNGO L. USING SEAWEED EXTRACT OF ULVA RETICULATA FORSSKAL.

OpenAIRE

Ganapathy Selvam G.; Balamurugan M.; Thinakaran T.; Sivakumar K

2013-01-01

The effect of seaweed extract prepared from Ulva reticulata on seed germination, seedling growth and chlorophyllase activity of Vigna mungo L. was studied. 100% germination was recorded in the seeds treated with lower concentration of seaweed extract. The V. mungo seeds soaked with lower concentrations of the seaweed extracts showed higher rates of germination, while the higher concentrations of the extracts inhibited the germination.

SSH reveals a linkage between a senescence-associated protease and Verticillium wilt symptom development in lettuce (Lactuca sativa)

Science.gov (United States)

Suppression subtractive hybridization (SSH) was employed to identify lettuce (Lactuca sativa) genes that are differentially expressed in symptomatic leaves infected with Verticillium dahliae. Genes expressed only in symptomatic leaves included those with homology to pathogenesis-related (PR) protei...

Effect of fly-ash amended soil on growth of Lactuca sativa L

Energy Technology Data Exchange (ETDEWEB)

Srivastava, K.; Farooqui, A.; Kulshreshtha, K.; Ahmad, K.J. [National Botanical Research Institute, Lucknow (India). Environmental Botany Lab.

1995-04-01

The present study has been undertaken with a view to evaluate the impact of fly-ash amended soil on growth and photosynthetic pigments of Lactuca sativa L. It was seen that 10% treatment showed marked increase in plant growth while 20-30% treated plants showed retarded growth as compared to control. Similar trends of increase and decrease in pigment formation was also observed. Results indicate the utilization of fly-ash in low concentrations for better growth, dry matter production and increased photosynthetic pigments.

The appearance of Ulva laetevirens (Ulvophyceae, Chlorophyta) in the northeast coast of the United States of America

Science.gov (United States)

Mao, Yunxiang; Kim, Jang Kyun; Wilson, Roderick; Yarish, Charles

2014-10-01

Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species, which was found in an embayment (Holly Pond) connected with Long Island Sound, USA. The morphological and anatomical observations in combination with molecular data were used for its identification to species. Anatomy of collected specimens showed that the cell shape in rhizoidal and basal regions was round and the marginal teeth along the basal and median region were not found. These characteristics were primarily identical to the diagnostic characteristics of Ulva laetevirens Areschoug (Chlorophyta). The plastid-encoding tufA and nucleusencoding ITS1 were used for its molecular identification. Phylogenetic analysis for the tufA gene placed the specimens from Holly Pond in a well-supported clade along with published sequences of U. laetevirens identified early without any sequence divergence. In ITS tree, the sample also formed well-supported clades with the sequences of U. laetevirens with an estimated sequence divergence among the taxa in these clades as low as 1%. These findings confirmed the morpho-anatomical conclusion. Native to Australia, this species was reported in several countries along the Mediterranean coast after the late of 1990s. This is the first time that U. laetevirens is found in the northeast coast of United States and the second record for Atlantic North America.

Temporal trending of lead and cadmium contamination in the Vigo estuary intertidal area Evolución temporal de la contaminación por plomo y cadmio en la zona intermareal de la ría de Vigo

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J. Alonso Díaz

2004-12-01

Full Text Available At the present work, limpet (Patella vulgata L. and seaweed (Ulva lactuca specimens have been monthly sampled at the same point from the Vigo estuary, during a year. Heavy metal (cadmium and lead content has been determined by means of differential pulse anodic stripping voltammetry in both limpet and seaweed tissues, as well as in seawater. The obtained results have shown the main heavy metal content in limpet soft tissues with respect to shell, with maximum concentrations of 3 ppm (limpet shell for lead, whereas the highest content for cadmium was identified in seaweed samples (1.1 ppm. The statistical study revealed the existence of a clear correlation between cadmium and lead concentrations in seaweed samples.En el presente trabajo se han recogido muestras de lapa (Patella vulgata L. y alga verde (Ulva lactuca en un mismo punto de muestreo de la ría de Vigo, con una periodicidad mensual, a lo largo de un año, analizándose por medio de voltamperometría de redisolución anódica la concentración en dos metales pesados con claras repercusiones toxicológicas, cadmio y plomo, en estas muestras, así como en el agua marina. Los resultados obtenidos mostraron la mayor concentración de ambos metales en los tejidos blandos de las lapas frente a las valvas de estos moluscos, con valores máximos en el caso del plomo próximos a 3 ppm (valva de lapa, mientras que para el cadmio se situó en torno a 1,1 ppm (alga verde. El estudio estadístico permitió poner en evidencia una clara correlación estadística entre los valores de cadmio y plomo cuantificados en las muestras de algas.

Guaiane sesquiterpenes from seaweed Ulva fasciata Delile and their antibacterial properties.

Science.gov (United States)

Chakraborty, Kajal; Lipton, A P; Paulraj, R; Chakraborty, Rekha D

2010-06-01

Two new guaiane sesquiterpene derivatives, guai-2-en-10alpha-ol (1) and guai-2-en-10alpha-methanol (2), were chromatographically purified as major constituents of the CHCl3/CH3OH (1:1, v/v) soluble fraction of Ulva fasciata. Acetylation of 2 furnished guai-2-en-10alpha-methyl methanoate (3) with acetyl group at C11 position. The structures of the compounds were elucidated using one and two-dimensional NMR and mass spectrometric analysis. Compounds 2 and 3 exhibited significant inhibition to the growth of Vibrio parahaemolyticus with minimum inhibitory concentrations of 25 and 35 microg/mL, respectively. The electronegative C10 acetyl group with high polarisability (7.02x10(-24) cm3) in 3 appeared to withdraw electron cloud from substituted cycloheptyl ring and (R)-3-methylcyclohept-1-ene moiety, thus acting as the nucleophilic center of the molecule resulting in high bioactivity. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

Science.gov (United States)

Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

Effect of crude seaweed extracts on seed germination, seedling growth and some metabolic processes of Vicia faba L.

Science.gov (United States)

el-Sheekh, M M; el-Saied A el-D

2000-01-01

Crude extracts from three green seaweeds (Cladophora dalmatica, Enteromorpha intestinalis, Ulva lactuca) and the three red algae (Corallina mediterranea, Jania rubens, Pterocladia pinnate) were prepared. Their effects on germination, growth of seedlings, chlorophyll content and other metabolic activities of Vicia faba were investigated. The crude extract of C. dalmatica showed maximal activity, and it increased seed germination, length of main root and shoot systems and the number of lateral roots. All the crude extracts of seaweed increased protein content in both root and shoot systems, total soluble sugars and chlorophyll content in leaves. The cytokinin content of the green algae was higher than that in red algae. Growth of seedlings of V. faba was stimulated but to different degrees.

Gas Chromatography-Mass Spectrometry Analysis of Ulva fasciata (Green Seaweed) Extract and Evaluation of Its Cytoprotective and Antigenotoxic Effects.

Science.gov (United States)

Rodeiro, Idania; Olguín, Sitlali; Santes, Rebeca; Herrera, José A; Pérez, Carlos L; Mangas, Raisa; Hernández, Yasnay; Fernández, Gisselle; Hernández, Ivones; Hernández-Ojeda, Sandra; Camacho-Carranza, Rafael; Valencia-Olvera, Ana; Espinosa-Aguirre, Jesús Javier

2015-01-01

The chemical composition and biological properties of Ulva fasciata aqueous-ethanolic extract were examined. Five components were identified in one fraction prepared from the extract by gas chromatography-mass spectrometry, and palmitic acid and its ethyl ester accounted for 76% of the total identified components. Furthermore, we assessed the extract's antioxidant properties by using the DPPH, ABTS, and lipid peroxidation assays and found that the extract had a moderate scavenging effect. In an experiment involving preexposition and coexposition of the extract (1-500 µg/mL) and benzo[a]pyrene (BP), the extract was found to be nontoxic to C9 cells in culture and to inhibit the cytotoxicity induced by BP. As BP is biotransformed by CYP1A and CYP2B subfamilies, we explored the possible interaction of the extract with these enzymes. The extract (25-50 µg/mL) inhibited CYP1A1 activity in rat liver microsomes. Analysis of the inhibition kinetics revealed a mixed-type inhibitory effect on CYP1A1 supersome. The effects of the extract on BP-induced DNA damage and hepatic CYP activity in mice were also investigated. Micronuclei induction by BP and liver CYP1A1/2 activities significantly decreased in animals treated with the extract. The results suggest that Ulva fasciata aqueous-ethanolic extract inhibits BP bioactivation and it may be a potential chemopreventive agent.

Highly abundant and stage-specific mRNAs in the obligate pathogen Bremia lactucae.

Science.gov (United States)

Judelson, H S; Michelmore, R W

1990-01-01

Germinating spores of the obligate pathogen Bremia lactucae (lettuce downy mildew) contain several unusually abundant species of mRNA. Thirty-nine cDNA clones corresponding to prevalent transcripts were isolated from a library synthesized using poly(A)+ RNA from germinating spores; these clones represented only five distinct classes. Each corresponding mRNA accounted for from 0.4 to 9 percent by mass of poly(A)+ RNA from germinating spores and together represented greater than 20 percent of the mRNA. The expression of the corresponding genes, and a gene encoding Hsp70, was analyzed in spores during germination and during growth in planta. The Hsp70 mRNA and mRNA from one abundant cDNA clone (ham34) were expressed constitutively. Two clones (ham9 and ham12) hybridized only to mRNA from spores and germinating spores. Two clones (ham37 and ham27) showed hybridization specific to germinating spores. Quantification of the number of genes homologous to each cDNA clone indicated that four clones corresponded to one or two copies per haploid genome, and one hybridized to an approximately 11-member family of genes. A sequence of the gene corresponding to ham34 was obtained to investigate its function and to identify sequences conferring high levels of gene expression for use in constructing vectors for the transformation of B. lactucae.

Study on the Mediterranean coastal seaweed Ulva linza exposed to natural and stressed environmental conditions

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Ayman Abd Elmoneim El-Gamal

2015-10-01

Full Text Available Objective: To study Ulva linza (U. linza as macro-alga exposed to different levels of ionizing radiation from the natural background of radioactivity. Methods: Samples of U. linza were collected from two different habitats at the two terminals of the rocky shore of Abu Qir Bay, Alexandria, Egypt. The western terminal at Abu Qir represented an area of normal background radiation while the eastern terminal at Rosetta represented an area of relatively high background radiation. Distinguishing between the algae grown in areas of relatively high and normal background radiation was investigated by using different indicators. Moreover, the ambient water quality was measured and the concentrations of natural radionuclides (238U, 232Th and 40K bio-accumulated in the tested macro-alga were detected. Results: The algae naturally exposed to radionuclides (238U series, 232Th series and 40K were investigated. Radiation dose rates in U. linza inhabiting in Rosetta and Abu Qir were calculated as 70.12 and 42.67 nGy/h, respectively. Chemical analysis of algal samples demonstrated that total pigment contents were 2.21 and 2.19 mg/g on a fresh weight basis for U. linza inhabiting in Rosetta and Abu Qir, respectively. Fatty acid compositions showed comparable profiles for both algal samples with saturated fatty acids as major component. The results of protein profiles confirmed slight differential expression in protein bands. Sequence-related randomly amplified polymorphic DNA provided evidence that both samples were strongly similar. By using transmission electron microscopy, no obvious ultra structural changes in the examined cells were observed. Conclusions: These experimental results demonstrate that radiation doses are not high enough to cause damage or manifest any significant variation in Ulva tissues.

Alternative electron transports participate in the maintenance of violaxanthin De-epoxidase activity of Ulva sp. under low irradiance.

Science.gov (United States)

Xie, Xiujun; Gu, Wenhui; Gao, Shan; Lu, Shan; Li, Jian; Pan, Guanghua; Wang, Guangce; Shen, Songdong

2013-01-01

The xanthophyll cycle (Xc), which involves violaxanthin de-epoxidase (VDE) and the zeaxanthin epoxidase (ZEP), is one of the most rapid and efficient responses of plant and algae to high irradiance. High light intensity can activate VDE to convert violaxanthin (Vx) to zeaxanthin (Zx) via antheraxanthin (Ax). However, it remains unclear whether VDE remains active under low light or dark conditions when there is no significant accumulation of Ax and Zx, and if so, how the ΔpH required for activation of VDE is built. In this study, we used salicylaldoxime (SA) to inhibit ZEP activity in the intertidal macro-algae Ulva sp. (Ulvales, Chlorophyta) and then characterized VDE under low light and dark conditions with various metabolic inhibitors. With inhibition of ZEP by SA, VDE remained active under low light and dark conditions, as indicated by large accumulations of Ax and Zx at the expense of Vx. When PSII-mediated linear electron transport systems were completely inhibited by SA and DCMU, alternative electron transport systems (i.e., cyclic electron transport and chlororespiration) could maintain VDE activity. Furthermore, accumulations of Ax and Zx decreased significantly when SA, DCMU, or DBMIB together with an inhibitor of chlororespiration (i.e., propyl gallate (PG)) were applied to Ulva sp. This result suggests that chlororespiration not only participates in the build-up of the necessary ΔpH, but that it also possibly influences VDE activity indirectly by diminishing the oxygen level in the chloroplast.

Alternative electron transports participate in the maintenance of violaxanthin De-epoxidase activity of Ulva sp. under low irradiance.

Directory of Open Access Journals (Sweden)

Xiujun Xie

Full Text Available The xanthophyll cycle (Xc, which involves violaxanthin de-epoxidase (VDE and the zeaxanthin epoxidase (ZEP, is one of the most rapid and efficient responses of plant and algae to high irradiance. High light intensity can activate VDE to convert violaxanthin (Vx to zeaxanthin (Zx via antheraxanthin (Ax. However, it remains unclear whether VDE remains active under low light or dark conditions when there is no significant accumulation of Ax and Zx, and if so, how the ΔpH required for activation of VDE is built. In this study, we used salicylaldoxime (SA to inhibit ZEP activity in the intertidal macro-algae Ulva sp. (Ulvales, Chlorophyta and then characterized VDE under low light and dark conditions with various metabolic inhibitors. With inhibition of ZEP by SA, VDE remained active under low light and dark conditions, as indicated by large accumulations of Ax and Zx at the expense of Vx. When PSII-mediated linear electron transport systems were completely inhibited by SA and DCMU, alternative electron transport systems (i.e., cyclic electron transport and chlororespiration could maintain VDE activity. Furthermore, accumulations of Ax and Zx decreased significantly when SA, DCMU, or DBMIB together with an inhibitor of chlororespiration (i.e., propyl gallate (PG were applied to Ulva sp. This result suggests that chlororespiration not only participates in the build-up of the necessary ΔpH, but that it also possibly influences VDE activity indirectly by diminishing the oxygen level in the chloroplast.

The effect of outer space environments on Lactuca sativa seeds flown on Cosmos biosatellites

International Nuclear Information System (INIS)

Nevzgodina, L.V.; Maksimova, E.N.; Akatov, Yu.A.; Kaminskaya, E.V.; Marennyj, A.M.

1990-01-01

The effect of cosmic radiation on air-dry lettuce (Lactuca sativa) seeds was investigated. It was attempted to discriminate the effects of cosmic ionizing radiation per se and its combination with solar light radiation. It was found that the number of aberrant cells in the seeds exposed to solar light was smaller than that of cells chielded with 0.0008 to 0.0035 g/cm 3 foil which could be attributed to photoreactivity

Enzymatic saccharification of seaweeds into fermentable sugars by xylanase from marine Bacillus sp. strain BT21.

Science.gov (United States)

Parab, Pankaj; Khandeparker, Rakhee; Amberkar, Ujwala; Khodse, Vishwas

2017-10-01

Enzymatic hydrolysis of seaweed biomass was studied using xylanase produced from marine bacteria Bacillus sp. strain BT21 through solid-state fermentation of wheat bran. Three types of seaweeds, Ahnfeltia plicata , Padina tetrastromatica and Ulva lactuca , were selected as representatives of red, brown, and green seaweeds, respectively. Seaweed biomass was pretreated with hot water. The efficiency of pretreated biomass to release reducing sugar by the action of xylanase as well as the type of monosaccharide released during enzyme saccharification of seaweed biomass was studied. It was seen that pretreated biomass of seaweed A. plicata, U. lactuca , and P. tetrastroma , at 121 °C for 45 min, followed by incubation with 50 IU xylanase released reducing sugars of 233 ± 5.3, 100 ± 6.1 and 73.3 ± 4.1 µg/mg of seaweed biomass, respectively. Gas chromatography analysis illustrated the release of xylose, glucose, and mannose during the treatment process. Hot water pre-treatment process enhanced enzymatic conversion of biomass into sugars. This study revealed the important role of xylanase in saccharification of seaweed, a promising feedstock for third-generation bioethanol production.

Experimental determinations of soil copper toxicity to lettuce (Lactuca sativa) growth in highly different copper spiked and aged soils

DEFF Research Database (Denmark)

Christiansen, Karen Søgaard; Borggaard, Ole K.; Holm, Peter Engelund

2015-01-01

Accurate knowledge about factors and conditions determining copper (Cu) toxicity in soil is needed for predicting plant growth in various Cu-contaminated soils. Therefore, effects of Cu on growth (biomass production) of lettuce (Lactuca sativa) were tested on seven selected, very different soils...

Distribution of genetic diversity in wild European populations of prickly lettuce (Lactuca serriola): implications for plant genetic resources management

NARCIS (Netherlands)

Wiel, van de C.C.M.; Sretenovic Rajicic, T.; Treuren, van R.; Dehmer, K.J.; Linden, van der C.G.; Hintum, van T.J.L.

2010-01-01

Genetic variation in Lactuca serriola, the closest wild relative of cultivated lettuce, was studied across Europe from the Czech Republic to the United Kingdom, using three molecular marker systems, simple sequence repeat (SSR, microsatellites), AFLP and nucleotide-binding site (NBS) profiling. The

In intro antioxidant activities of different sulfated polysaccharides from chlorophytan seaweeds Ulva fasciata.

Science.gov (United States)

Shao, Ping; Chen, Meng; Pei, Yaping; Sun, Peilong

2013-08-01

Four different molecular weight sulfated polysaccharides (UFP1, UFP2, UFP3 and UFP4) were extracted and separated from Ulva fasciata by hot water extraction and ultrafiltration. Their chemical and physical characteristics were determined and antioxidant activities were investigated on the basis of superoxide radical assay, hydroxyl radical assay, ABTS radical assay, and reducing power assay. The results showed that four polysaccharides exhibited antioxidant properties, and UFP2 and UFP3, which have lower content of sulfate showed higher antioxidant activities than UFP1 and UFP4, which have higher content of sulfate. Besides, the content of protein, uronic acid and molecular weights of polysaccharides also influence their antioxidant activities. The antioxidant activities of UFP were not a function of a single factor but a combination of several factors. Copyright © 2013 Elsevier B.V. All rights reserved.

LSGermOPA, a custom OPA of 384 EST-derived SNPs for high-throughput lettuce (Lactuca sativa L.) germplasm fingerprinting

Science.gov (United States)

We assessed the genetic diversity and population structure among 148 cultivated lettuce (Lactuca sativa L.) accessions using the high-throughput GoldenGate assay and 384 EST (Expressed Sequence Tag)-derived SNP (single nucleotide polymorphism) markers. A custom OPA (Oligo Pool All), LSGermOPA was fo...

A note on the measurement of genetic diversity within genebank accessions of lettuce (Lactuca sativa L.) using AFLP markers

NARCIS (Netherlands)

Jansen, J.; Verbakel, H.; Peleman, J.; Hintum, van T.J.L.

2006-01-01

This paper discusses a statistical approach for measuring genetic diversity within genebank accessions of a self-fertilising species. This approach is applied to lettuce (Lactuca sativa L.), using AFLP marker data on a set of 1,390 accessions, representing six different lettuce types. Knowledge of

Metal accumulation and oxidative stress responses in Ulva spp. in the presence of nocturnal pulses of metals from sediment: A field transplantation experiment under eutrophic conditions

KAUST Repository

Pereira, Patrícia M R

2014-03-01

In aquatic systems under eutrophic conditions, remobilization of metals from sediment to the overlying water may occur. Consequently, adaptive responses of local organisms could result from the accumulation of metals intermittently released from the sediment. In summer 2007, a field transplantation experiment was performed in the Óbidos lagoon (Portugal) with Ulva spp. comprising three short-term exposures (between 15:30-23:30; 23:30-07:30; 07:30-15:30) during a 24-h period. In each period, Ulva spp. was collected at a reference site located in the lower lagoon (LL) and transplanted to a eutrophic site located at the Barrosa branch (BB), characterized by moderate metal contamination. For comparison purposes, macroalgae samples were simultaneously exposed at LL under the same conditions. Both sites were surveyed in short-time scales (2-4 h) for the analysis of the variability of physical-chemical parameters in the water and metal levels in suspended particulate matter. The ratios to Al of particulate Mn, Fe, Cu and Pb increased during the period of lower water oxygenation at the eutrophic site, reaching 751 × 10-4, 0.67, 12 × 10-4, 9.9 × 10-4, respectively, confirming the release of metals from the sediment to water during the night. At the reference site, dissolved oxygen oscillated around 100%, Mn/Al ratios were considerably lower (81 × 10-4-301 × 10-4) compared to BB (234 × 10-4-790 × 10-4), and no increases of metal/Al ratios were found during the night. In general, algae uptake of Mn, Cu, Fe, Pb and Cd was significantly higher at the eutrophic site compared to the reference site. The results confirmed the potential of Ulva spp. as bioindicator of metal contamination and its capability to respond within short periods. An induction of SOD, an inhibition of CAT and the increase of LPO were recorded in Ulva spp. exposed at BB (between 23:30 and 7:30) probably as a response to the higher incorporation of Mn, Fe and Pb in combination with the lack of

Evaluation of the antidepressant- and anxiolytic-like effects of a hydrophilic extract from the green seaweed Ulva sp. in rats.

Science.gov (United States)

Violle, Nicolas; Rozan, Pascale; Demais, Hervé; Nyvall Collen, Pi; Bisson, Jean-François

2018-05-01

The green seaweed Ulva sp. contains a large amount of ulvans, a family of sulphated polysaccharides. The present study was designed to investigate in rats the antidepressant- and anxiolytic-like effects of a hydrophilic extract of Ulva sp. (MSP) containing about 45% of ulvans. After a 14-day administration of MSP at doses of 10, 20 and 40 mg/kg/day, 48 and 60 male adult Wistar rats were respectively tested in the elevated plus-maze (EPM) and the forced swimming test (FST). In the FST, MSP effects were compared to the reference antidepressant drug imipramine (IMI) (10 mg/kg/day). Acute and sub-chronic toxicities of the extract were also assessed in male and female rats following OECD guidelines. MSP treatment did not modify anxiety-related behaviour in the EPM. In contrast, MSP induced a dose-dependent reduction of immobility behaviour in the FST. At the highest tested dose of 40 mg/kg, MSP displayed a significant antidepressant-like effect similar to IMI. MSP did not modify the exploratory behaviour of rats in the open field test and did not produce any toxic effect. MSP may potentially represent a good adjunct or alternative to existing antidepressant therapeutics. Further studies are necessary to confirm the mechanism of action of MSP and its modulation of brain functioning.

Evaluation of the plant growth-promoting activity of Pseudomonas nitroreducens in Arabidopsis thaliana and Lactuca sativa.

Science.gov (United States)

Trinh, Cao Son; Lee, Hyeri; Lee, Won Je; Lee, Seok Jin; Chung, Namhyun; Han, Juhyeong; Kim, Jongyun; Hong, Suk-Whan; Lee, Hojoung

2018-06-01

Pseudomonas nitroreducens: strain IHB B 13561 (PnIHB) enhances the growth of Arabidopsis thaliana and Lactuca sativa via the stimulation of cell development and nitrate absorption. Plant growth-promoting rhizobacteria (PGPR) enhance plant development through various mechanisms; they improve the uptake of soil resources by plants to greatly promote plant growth. Here, we used Arabidopsis thaliana seedlings and Lactuca sativa to screen the growth enhancement activities of a purified PGPR, Pseudomonas nitroreducens strain IHB B 13561 (PnIHB). When cocultivated with PnIHB, both species of plants exhibited notably improved growth, particularly in regard to biomass. Quantitative reverse transcription polymerase chain reaction analysis indicated high expression levels of the nitrate transporter genes, especially NRT2.1, which plays a major role in the high-affinity nitrate transport system in roots. Moreover, enhanced activity of the cyclin-B1 promoter was observed when wild-type 'Columbia-0' Arabidopsis seedlings were exposed to PnIHB, whereas upregulation of cyclin-B also occurred in the inoculated lettuce seedlings. Overall, these results suggest that PnIHB improves A. thaliana and L. sativa growth via specific pathways involved in the promotion of cell development and enhancement of nitrate uptake.

Rheology and characteristics of sulfated polysaccharides from chlorophytan seaweeds Ulva fasciata.

Science.gov (United States)

Shao, Ping; Qin, Minpu; Han, Longfei; Sun, Peilong

2014-11-26

The rheological characteristics of polysaccharides which were extracted and separated from Ulva fasciata (UFP) were investigated in aqueous solutions under conditions of concentration, temperature, solution pH and salt concentrations. It was described by the power-law model with a consistency index (k) and a flow behavior index (n). The rheology results showed UFP exhibited as a shear-thickening fluid and a possible mechanism was proposed to explain this phenomenon that might be the collapse of UFP necklace-type structures. UFP characteristics were evaluated by determining the chemical analysis and zeta potential. The findings indicated UFP may consist of partially ulvan, as the results were in accordance with the ulvan structure. Additionally, a rod-climbing effect and cold-set gelation were observed in the UFP semidilute solution. Therefore, the cold-set gelling properties and unique shear-thickening fluid properties in this work could be valuable for the exploration of U. fasciata as a new source of water-soluble gelling polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gas Chromatography-Mass Spectrometry Analysis of Ulva fasciata (Green Seaweed Extract and Evaluation of Its Cytoprotective and Antigenotoxic Effects

Directory of Open Access Journals (Sweden)

Idania Rodeiro

2015-01-01

Full Text Available The chemical composition and biological properties of Ulva fasciata aqueous-ethanolic extract were examined. Five components were identified in one fraction prepared from the extract by gas chromatography-mass spectrometry, and palmitic acid and its ethyl ester accounted for 76% of the total identified components. Furthermore, we assessed the extract’s antioxidant properties by using the DPPH, ABTS, and lipid peroxidation assays and found that the extract had a moderate scavenging effect. In an experiment involving preexposition and coexposition of the extract (1–500 µg/mL and benzo[a]pyrene (BP, the extract was found to be nontoxic to C9 cells in culture and to inhibit the cytotoxicity induced by BP. As BP is biotransformed by CYP1A and CYP2B subfamilies, we explored the possible interaction of the extract with these enzymes. The extract (25–50 µg/mL inhibited CYP1A1 activity in rat liver microsomes. Analysis of the inhibition kinetics revealed a mixed-type inhibitory effect on CYP1A1 supersome. The effects of the extract on BP-induced DNA damage and hepatic CYP activity in mice were also investigated. Micronuclei induction by BP and liver CYP1A1/2 activities significantly decreased in animals treated with the extract. The results suggest that Ulva fasciata aqueous-ethanolic extract inhibits BP bioactivation and it may be a potential chemopreventive agent.

Genetic Transformation and Hairy Root Induction Enhance the Antioxidant Potential of Lactuca serriola L.

Directory of Open Access Journals (Sweden)

Mohamed A. El-Esawi

2017-01-01

Full Text Available Lactuca serriola L. is a herbaceous species, used for human nutrition and medicinal purposes. The high antioxidant capacity of L. serriola indicates the possibility of enhancing its edible and health potential by increasing the flavonoid and phenolic contents. The present study aimed at enhancing the production of phenolics and flavonoids by hairy root cultures in Lactuca serriola transformed with Agrobacterium rhizogenes strain AR15834 harbouring the rolB gene. The genetic transformation of rolB in transformed roots was validated, and rolB expression level was evaluated using real-time qPCR analysis. Expression levels of flavonoid biosynthesis genes (CHI, PAL, FLS, and CHS were assessed in the hairy and nontransformed roots. Results showed higher expression levels in the transgenic roots than in the nontransformed ones (p<0.01. Transgenic hairy roots exhibited a 54.8–96.7% increase in the total phenolic content, 38.1–76.2% increase in the total flavonoid content, and 56.7–96.7% increase in the total reducing power when compared with the nontransgenic roots (p<0.01. DPPH results also revealed that the transgenic hairy roots exhibited a 31.6–50% increase in antioxidant potential, when compared to normal roots. This study addressed the enhancement of secondary metabolite biosynthesis by hairy root induction in L. serriola.

Elucidating the genetic basis of antioxidant status in lettuce (Lactuca sativa).

Science.gov (United States)

Damerum, Annabelle; Selmes, Stacey L; Biggi, Gaia F; Clarkson, Graham Jj; Rothwell, Steve D; Truco, Maria José; Michelmore, Richard W; Hancock, Robert D; Shellcock, Connie; Chapman, Mark A; Taylor, Gail

2015-01-01

A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases, but many of the most popular vegetables are low in phytonutrients. Wild relatives of crops may contain allelic variation for genes determining the concentrations of these beneficial phytonutrients, and therefore understanding the genetic basis of this variation is important for breeding efforts to enhance nutritional quality. In this study, lettuce recombinant inbred lines, generated from a cross between wild and cultivated lettuce (Lactuca serriola and Lactuca sativa, respectively), were analysed for antioxidant (AO) potential and important phytonutrients including carotenoids, chlorophyll and phenolic compounds. When grown in two environments, 96 quantitative trait loci (QTL) were identified for these nutritional traits: 4 for AO potential, 2 for carotenoid content, 3 for total chlorophyll content and 87 for individual phenolic compounds (two per compound on average). Most often, the L. serriola alleles conferred an increase in total AOs and metabolites. Candidate genes underlying these QTL were identified by BLASTn searches; in several cases, these had functions suggesting involvement in phytonutrient biosynthetic pathways. Analysis of a QTL on linkage group 3, which accounted for >30% of the variation in AO potential, revealed several candidate genes encoding multiple MYB transcription factors which regulate flavonoid biosynthesis and flavanone 3-hydroxylase, an enzyme involved in the biosynthesis of the flavonoids quercetin and kaempferol, which are known to have powerful AO activity. Follow-up quantitative RT-PCR of these candidates revealed that 5 out of 10 genes investigated were significantly differentially expressed between the wild and cultivated parents, providing further evidence of their potential involvement in determining the contrasting phenotypes. These results offer exciting opportunities to improve the nutritional

Ulva and Enteromorpha (Ulvaceae, Chlorophyta) from two sides of the Yellow Sea: analysis of nuclear rDNA ITS and plastid rbcL sequence data

Science.gov (United States)

Wang, Jinfeng; Li, Nan; Jiang, Peng; Boo, Sung Min; Lee, Wook Jae; Cui, Yulin; Lin, Hanzhi; Zhao, Jin; Liu, Zhengyi; Qin, Song

2010-07-01

Ulvacean green seaweeds are common worldwide; they formed massive green tides in the Yellow Sea in recent years, which caused marine ecological problems as well as a social issue. We investigated two major genera of the Ulvaceae, Ulva and Enteromorpha, and collected the plastid rbcL and nuclear ITS sequences of specimens of the genera in two sides of the Yellow Sea and analyzed them. Phylogenetic trees of rbcL data show the occurrence of five species of Enteromorpha ( E. compressa, E. flexuosa, E. intestinalis, E. linza and E. prolifera) and three species of Ulva ( U. pertusa, U. rigida and U. ohnoi). However, we found U. ohnoi, which is known as a subtropical to tropical species, at two sites on Jeju Island, Korea. Four ribotypes in partial sequences of 5.8S rDNA and ITS2 from E. compressa were also found. Ribotype network analysis revealed that the common ribotype, occurring in China, Korea and Europe, is connected with ribotypes from Europe and China/Japan. Although samples of the same species were collected from both sides of the Yellow Sea, intraspecific genetic polymorphism of each species was low among samples collected worldwide.

Molecular aspects of the antagonistic interaction of smoke-derived butenolides on the germination process of Grand Rapids lettuce (Lactuca sativa) achenes

Czech Academy of Sciences Publication Activity Database

Soós, V.; Sebestyén, E.; Pošta, Martin; Kohout, Ladislav; Light, M. E.; van Staden, J.; Balázs, E.

2012-01-01

Roč. 196, č. 4 (2012), s. 1060-1073 ISSN 0028-646X Institutional research plan: CEZ:AV0Z40550506 Keywords : abscisic acid * fire * germination * karrikinolide * Lactuca sativa * smoke Subject RIV: CE - Biochemistry Impact factor: 6.736, year: 2012

Enteroparasitas em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR / Enteroparasites on commercial lettuce (Lactuca sativa in Guarapuava City, Paraná State

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Silvia Cristina Osaki

2010-08-01

Full Text Available O consumo de hortaliças cruas constitui importante meio de transmissão de enteroparasitoses. O objetivo deste trabalho foi avaliar a contaminação parasitária em alfaces (Lactuca sativa comercializadas na cidade de Guarapuava (PR. No período de julho/2005 a junho/2006, 52 supermercados foram visitados, com colheita de um pé de alface. A análise parasitológica foi realizada após duas lavagens, filtragem em gaze e sedimentação. O sedimento, corado pelo lugol, foi analisado microscopicamente por exame direto e após centrífugo-flutuação em sulfato de zinco. Das 52 amostras de alface avaliadas, 18 (34,6% apresentaram uma ou mais estruturas parasitárias como cistos de Giardia spp. (7,7%, de Entamoeba spp. (11,5% e de Balantidium coli (3,8%, oocistos de coccídios (7,7% e ovos de Capillaria spp. (3,8%. Esse alto número de amostras contaminadas aponta deficiências na cadeia produtiva dessas hortaliças, indicando a necessidade de adequada higienização antes de seu consumo. AbstractThe ingestion of raw vegetables is an important mode of enteroparasites transmission. The aim of this study was to evaluate the parasitological contamination of lettuce (Lactuca sativa commercialized in Guarapuava City, Parana State. Fifty-two samples of lettuce were collected from supermarkets during the period of July 2005 and June 2006. Parasitological analysis was realized by the sedimentation technique. Lugol-stained sediments were microscopically analyzed by direct exam and after centrifugation-fluctuation in zinc sulfate. A total of 18 out of 52 lettuce samples analyzed (34.6% were positive for one or more parasitic structures. The parasites found in the analysis were Giardia spp. (7.7%, Entamoeba spp. (11.5%, Balantidium coli (3.8%, coccidian oocysts (7.7% and Capillaria spp. eggs (3.8%. Such high occurrence of contaminated samples revealed deficiencies in the chain of lettuce cultivation, which suggests a need for improvement in the current

Antioxidant activity and mineral composition of three Mediterranean common seaweeds from Abu-Qir Bay, Egypt

Science.gov (United States)

Khairy, Hanan M.; El-Sheikh, Mohamed A.

2015-01-01

Antioxidant activity and mineral composition were evaluated seasonally from spring to autumn 2010 in the three common seaweeds Ulva lactuca Linnaeus (Chlorophyta), Jania rubens (Linnaeus) J.V. Lamouroux and Pterocladia capillacea (S.G. Gmelin) Bornet (Rhodophyta). The antioxidant activity was measured with β-carotene, total phenol content and DPPH (2,2-diphenyl-1-picrylhydrazyl). Seaweeds were collected from the rocky site near Boughaz El-Maadya Abu-Qir Bay of Alexandria, Egypt. The results showed maximum increase of β-carotene in P. capillacea during summer. A significant increase in total phenolic content at P ⩽ 0.05 was found in the red alga (J. rubens) during summer. Also, U. lactuca showed the maximum antioxidant scavenging activity especially during summer. Minerals in all investigated samples were higher than those in conventional edible vegetables. Na/K ratio ranged between 0.78 and 2.4 mg/100 g, which is a favorable value. All trace metals exceeded the recommended doses by Reference Nutrient Intake (RNI). During summer season, it was found that Cu = 2.02 ± 0.13 and Cr = 0.46 ± 0.14 mg/100 g in U. lactuca and Fe had a suitable concentration (18.37 ± 0.5 mg/100 g) in P. capillacea. The studied species were rich in carotenoids, phenolic compounds, DPPH free radicals and minerals, therefore, they can be used as potential source of health food in human diets and may be of use to food industry. PMID:26288568

Optical properties of Lactuca and Taraxacum seed and fruit coats: Their role as light filters [phytochrome, photoblasty, fiber optics, transmission, spectra

International Nuclear Information System (INIS)

Widell, K.-O.; Vogelmann, T.C.

1985-01-01

The optical properties of seed and fruit coats were examined from several varieties of light-sensitive achenes. Taraxacum vulgare L. and Lactuca sativa L. cv. Grand Rapids achenes with dark fruit coats and L. sativa cvs Huvudsallat and Issallat with white fruit coats were examined. Transmission spectra varied among the different achenes: white fruit coats of Lactuca acted as neutral density filters between 450 and 780 nm, whereas Taraxacum transmitted 2–36% in this region. The ribbed fruit coat structure greatly affected transmission so that at different locations in the same coat, transmission varied between 20 to 80% at 660 and 730 nm. Fruit coats of Grand Rapids lettuce and Taraxacum transmitted more far-red than red light with T 660 /T 730 ratios of 0.8 and 0.4, respectively. The relationship between the optical properties of fruit coats and light-stimulated germination is discussed. (author)

Plant growth-promoting bacterium Acinetobacter calcoaceticus P23 increases the chlorophyll content of the monocot Lemna minor (duckweed) and the dicot Lactuca sativa (lettuce).

Science.gov (United States)

Suzuki, Wakako; Sugawara, Masayuki; Miwa, Kyoko; Morikawa, Masaaki

2014-07-01

Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium that was isolated from the surface of duckweed (Lemna aoukikusa). The bacterium was observed to colonize on the plant surfaces and increase the chlorophyll content of not only the monocotyledon Lemna minor but also the dicotyledon Lactuca sativa in a hydroponic culture. This effect on the Lactuca sativa was significant in nutrient-poor (×1/100 dilution of H2 medium) and not nutrient-rich (×1 or ×1/10 dilutions of H2 medium) conditions. Strain P23 has the potential to play a part in the future development of fertilizers and energy-saving hydroponic agricultural technologies. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Ocorrência de raças de Bremia lactucae no Estado de São Paulo no triênio 2008 - 2010, e desenvolvimento de linhagens de alface crespa resistentes

OpenAIRE

Castoldi, Renata [UNESP

2011-01-01

A alface é a hortaliça folhosa de maior consumo no Brasil, no entanto a dificuldade em produzi-la vem aumentando, principalmente pela infestação das áreas de produção por Bremia lactucae, sendo necessário o monitoramento anual para utilização ou desenvolvimento de cultivares resistentes. Diante do exposto, os objetivos do presente trabalho foram: identificação de raças de B. lactucae no Estado de São Paulo, durante os anos de 2008, 2009 e 2010 e obtenção de linhagens de alface crespa resisten...

Toxicity Effect of Cr Stress on Seed Germination and Seedling Growth in Lactuca Sativa

Science.gov (United States)

Ma, Wan Zheng; Ma, Wan Min; Du, Ying Ying; Dan, Qiong Peng; Yin, Bing; Dai, Shan Shan; Hao, Xiang

2018-03-01

The impact of Cr6+ on the growth of lactuca sativa in Greenhouse Cucumber was investigated. The seeds of lacuna sativa Italian bolting resistance lettuce were treated by different Cr6+ concentration to study the effects on its seed germination and seedling growth. The results showed that the seed germination rate, vigor index of seedlings decreased with increment of Cr6+ concentration to varying degrees, and vigor germination, vigor index, raw weight, root length significantly lower. The absorption of lettuce seedlings on different nutrient elements is impacted by the concentration of Cr6+.

Characteristics and antioxidant of Ulva intestinalis sulphated polysaccharides extracted with different solvents.

Science.gov (United States)

Peasura, Napassorn; Laohakunjit, Natta; Kerdchoechuen, Orapin; Wanlapa, Sorada

2015-11-01

Ulva intestinalis, a tubular green seaweed, is a rich source of nutrient, especially sulphated polysaccharides. Sulphated polysaccharides from U. intestinalis were extracted with distilled water, 0.1N HCl, and 0.1N NaOH at 80°C for 1, 3, 6, 12, and 24h to study the effect of the extraction solvent and time on their chemical composition and antioxidant activity. Different types of solvents and extraction time had a significant influence on the chemical characteristics and antioxidant activity (pMonosaccharide composition and FT-IR spectra analyses revealed that sulphated polysaccharides from all solvent extractions have a typical sugar backbone (glucose, rhamnose, and sulphate attached at C-2 or C-3 of rhamnose). Sulphated polysaccharides extracted with acid exhibited greater antioxidant activity than did those extracted with distilled water and alkali. The results indicated that solvent extraction could be an efficacious method for enhancing antioxidant activity by distinct molecular weight and chemical characteristic of sulphated polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

Cross-shelf transport of sub-thermocline nitrate by the internal tide and rapid (3-6 h) incorporation by an inshore macroalga

Science.gov (United States)

Ladah, Lydia B.; Filonov, Anatoliy; Lavín, Miguel F.; Leichter, James J.; Zertuche-González, José A.; Pérez-Mayorga, Diana M.

2012-07-01

During summer in shallow waters off Baja California, Mexico, the internal tide is a dominant thermal feature of the water column. However, its importance for sub-thermocline nutrient provision to benthic macroalgae is unknown. In order to determine if internal motions provide nutrients to macroalgae in summer, Ulva lactuca was outplanted at inshore stations for short (3 and 6 h) intervals, at the surface, 5 and 10 m depth, and tissue nitrogen content was measured before and after each deployment. Concurrently temperature, currents, and nutrients were measured using moored thermistors, current profilers, CTDs, Niskin bottles, and an in-situ UV absorbance nitrate sensor (ISUS). Discrete pulses of cool, nutrient-rich water were horizontally displaced at least 4 km on the shelf and shoaled more than 20 m depth at the semidiurnal frequency, resulting in more than a 10-fold change in the concentration of nitrate. Inshore, tissue nitrogen of Ulva outplants increased significantly during longer exposures to this cool water. At this site, the semidiurnal signal dominates water column temperature fluctuations from April to November, with summer showing the greatest cooling (up to 5 °C) in a one-hour period. We estimated that 11% of the days of a year show internal waves that would cause a significant change in nutrient availability to macroalgae at 5 m depth. This study supports the hypothesis that nitrate can reach and be rapidly incorporated by inshore macroalgae such as Ulva through transport forced by the internal tide, and that even very short (internal tide provides a significant, yet understudied, high frequency nutrient source to inshore primary producers, particularly in summer.

Initiation and elongation of lateral roots in Lactuca sativa

Science.gov (United States)

Zhang, N.; Hasenstein, K. H.

1999-01-01

Lactuca sativa cv. Baijianye seedlings do not normally produce lateral roots, but removal of the root tip or application of auxin, especially indole-butyric acid, triggered the formation of lateral roots. Primordia initiated within 9 h and were fully developed after 24 h by activating the pericycle cells opposite the xylem pole. The pericycle cells divided asymmetrically into short and long cells. The short cells divided further to form primordia. The effect of root tip removal and auxin application was reversed by 6-benzylaminopurine at concentrations >10(-8) M. The cytokinin oxidase inhibitor N1-(2chloro4pyridyl)-N2-phenylurea also suppressed auxin-induced lateral rooting. The elongation of primary roots was promoted by L-alpha-(2-aminoethoxyvinyl) glycine and silver ions, but only the latter enhanced elongation of lateral roots. The data indicate that the induction of lateral roots is controlled by basipetally moving cytokinin and acropetally moving auxin. Lateral roots appear to not produce ethylene.

Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

Science.gov (United States)

He, Jinzhe; Xu, Yaoyang; Chen, Hongbo; Sun, Peilong

2016-01-01

Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material) on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM) with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW) distribution were analyzed by infrared (IR) spectrometry, gas chromatography (GC), and high-performance gel permeation chromatography (HPGPC). IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP), Ulva lactuca L. polysaccharide (ULLP), and Durvillaea antarctica polysaccharide (DAP) were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP), all belong to β-pyranosidic polysaccharides. The average molecular weight (MW) of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate) (ABTS), hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The

Extraction, Structural Characterization, and Potential Antioxidant Activity of the Polysaccharides from Four Seaweeds

Directory of Open Access Journals (Sweden)

Jinzhe He

2016-11-01

Full Text Available Four seaweed polysaccharides were extracted from Sarcodia ceylonensis, Ulva lactuca L., Gracilaria lemaneiformis, and Durvillaea antarctica, respectively, by microwave-assisted extraction. The effect of three significant variables (extraction time, extraction temperature, and the ratio of water to raw material on the process for extracting polysaccharides was investigated, along with the optimization of the extraction using the response surface method (RSM with a Box–Behnken design. The polysaccharide structure, monosaccharide composition, degree of sulfation, and molecular weight (MW distribution were analyzed by infrared (IR spectrometry, gas chromatography (GC, and high-performance gel permeation chromatography (HPGPC. IR spectrometry showed that Sarcodia ceylonensis polysaccharide (SCP, Ulva lactuca L. polysaccharide (ULLP, and Durvillaea antarctica polysaccharide (DAP were all sulfated polysaccharides and, except Gracilaria lemaneiformis polysaccharide (GLP, all belong to β-pyranosidic polysaccharides. The average molecular weight (MW of SCP, ULLP, GLP, and DAP was 466, 404, 591, and 482 kDa, respectively. The quantitative and comparative results with external standards indicated that the main monosaccharide in SCP and ULLP was mannose; and GLP and DAP were mainly composed of galactose and glucose, respectively. Then the in vitro antioxidant activity of all of the polysaccharides was evaluated using different assays—2,2–azino –bis (3-ethylbenzthiazoline-6- sulfonate (ABTS, hydroxyl radical, nitrite scavenging capacity, and reducing power—and the relationship between their antioxidant activity and chemical characteristics were also examined. ULLP presented the highest ABTS radical scavenging activity; ULLP, SCP and DAP also showed a strong effect on the ABTS radical scavenging activity. SCP and ULLP exhibited excellent hydroxyl radical scavenging activities, about 83.33% ± 2.31% and 80.07% ± 2.17%, respectively, at 4 mg/mL. The

Exogenous Glycine Nitrogen Enhances Accumulation of Glycosylated Flavonoids and Antioxidant Activity in Lettuce (Lactuca sativa L.)

OpenAIRE

Xiao Yang; Xiaoxian Cui; Xiaoxian Cui; Li Zhao; Doudou Guo; Lei Feng; Shiwei Wei; Chao Zhao; Chao Zhao; Danfeng Huang

2017-01-01

Glycine, the simplest amino acid in nature and one of the most abundant free amino acids in soil, is regarded as a model nutrient in organic nitrogen studies. To date, many studies have focused on the uptake, metabolism and distribution of organic nitrogen in plants, but few have investigated the nutritional performance of plants supplied with organic nitrogen. Lettuce (Lactuca sativa L.), one of the most widely consumed leafy vegetables worldwide, is a significant source of antioxidants and ...

Erythrocytes and cell line-based assays to evaluate the cytoprotective activity of antioxidant components obtained from natural sources.

Science.gov (United States)

Botta, Albert; Martínez, Verónica; Mitjans, Montserrat; Balboa, Elena; Conde, Enma; Vinardell, M Pilar

2014-02-01

Oxidative stress can damage cellular components including DNA, proteins or lipids, and may cause several skin diseases. To protect from this damage and addressing consumer's appeal to natural products, antioxidants obtained from algal and vegetal extracts are being proposed as antioxidants to be incorporated into formulations. Thus, the development of reliable, quick and economic in vitro methods to study the cytoactivity of these products is a meaningful requirement. A combination of erythrocyte and cell line-based assays was performed on two extracts from Sargassum muticum, one from Ulva lactuca, and one from Castanea sativa. Antioxidant properties were assessed in erythrocytes by the TBARS and AAPH assays, and cytotoxicity and antioxidant cytoprotection were assessed in HaCaT and 3T3 cells by the MTT assay. The extracts showed no antioxidant activity on the TBARS assay, whereas their antioxidant capacity in the AAPH assay was demonstrated. On the cytotoxicity assays, extracts showed low toxicity, with IC50 values higher than 200μg/mL. C. sativa extract showed the most favourable antioxidant properties on the antioxidant cytoprotection assays; while S. muticum and U. lactuca extracts showed a slight antioxidant activity. This battery of methods was useful to characterise the biological antioxidant properties of these natural extracts. Copyright © 2013 Elsevier Ltd. All rights reserved.

Alg Pigmentlerinin Tekstilde Doğal Boyar Madde Olarak Kullanımı

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Elif BAYRAKTAR

2018-04-01

Full Text Available Bu çalışmada, mikroalglerden Chlorella vulgaris Beyerinck (Beijerinck,  Porphyridium cruentum (S.F.Gray Nageli ve Haematococcus pluvialis Flotow ve makroalglerden  Ulva lactuca Linnaeus ve Gracilaria gracilis  (Stackhouse M.Steentoft, L.M.Irvine & W.F.Farnham türlerinden pigment ekstraksiyonu gerçekleştirilmiş ve elde edilen pigmentlerin tekstil sanayiinde doğal boyar madde olarak kullanımı konusunda verimliliği araştırılmıştır. Kulanılan türlerden üç farklı çözgen aracılığıyla pigment ekstraksiyonu gerçekleştirilmiş ve her ekstrakt için 4 farklı mordanlama kimyasalı kullanılmıştır. Boyama işleminde yün iplikten faydalanılmıştır. Boyanan ipliklerin ışık haslığına göre değerlendirilmiştir. İplik boyamada en etkili olan türlerin U. lactuca ve G. gracilis olduğu tespit edilmiştir. En iyi mordanlama ise CuSO4, FeSO4 kimyasalları ile gerçekleştirilmiştir.

Seasonal variation in the growth responses of some chlorophytic algal flora of the Red Sea

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Abid Ali Ansari

2017-06-01

Full Text Available Seasonal variation in growth responses and antioxidant activities of four chlorophytic algal species, namely Ulva lactuca, Enteromorpha flexuoca, Cladophora prolifera, Chaetomorpha linum was investigated. Seasonal variation in the physico-chemical characteristics of water at the study site of the Red Sea was also determined. A significant variation was observed in water quality parameters in different seasons. All the algal species show higher accumulation of photosynthetic and accessory pigments in July and October and a significant decrease in January. Higher NPK content in all the four algal species was recorded in July, however, the contents were low in other months. Total protein contents were higher in July and October. Total carbohydrates in U. lactuca and E. flexuoca were significantly higher in July but in the other two species, C. prolifera and C. linum, maximum accumulation was observed in October. Antioxidant activities in all the species were most significant in January as compared to the other months. All the chlorphytic algae show prominent growth responses and antioxidant activities and are better adapted to changing climatic conditions. Due to their prompt responses even to minor changes in aquatic environment, they can be used as ecological indicators in coastal marine ecosystems.

Accumulation of platinum group elements by the marine gastropod Littorina littorea

Energy Technology Data Exchange (ETDEWEB)

Mulholland, Rachel [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Turner, Andrew, E-mail: aturner@plymouth.ac.uk [School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2011-04-15

The accumulation and trophic transfer of the platinum group elements (PGE): Rh, Pd and Pt; have been studied in short-term (5 day) exposures conducted in aquaria containing the marine macroalga, Ulva lactuca, and/or the grazing mollusc, Littorina littorea. Metals added to sea water (to concentrations of 20 {mu}g L{sup -1}) were taken up by U. lactuca in the order Rh, Pt > Pd and by L. littorea in the order Pd {>=} Pt {>=} Rh, with greatest metal accumulation in the latter generally occurring in the visceral complex and kidney. When fed contaminated alga, accumulation of Rh and Pd by L. littorea, relative to total available metal, increased by an order of magnitude, while accumulation of Pt was not readily detected. We conclude that the diet is the most important vector for accumulation of Rh and Pd, while accumulation of Pt appears to proceed mainly from the aqueous phase. - Research highlights: > Platinum group elements are accumulated by, Littorina littorea. > The aqueous phase and diet are important vehicles for Rh and Pd accumulation by the snail. > Grazing molluscs may serve as biomonitors of coastal PGE contamination. - Platinum group elements are accumulated by the marine snail, Littorina littorea, from both the aqueous phase and the diet.

Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

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Aline P. Martins

2012-08-01

Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

Comparison of extraction and transesterification methods on the determination of the fatty acid contents of three Brazilian seaweed species

Directory of Open Access Journals (Sweden)

Aline P. Martins

2012-06-01

Full Text Available Seaweeds are photosynthetic organisms important to their ecosystem and constitute a source of compounds with several different applications in the pharmaceutical, cosmetic and biotechnology industries, such as triacylglycerols, which can be converted to fatty acid methyl esters that make up biodiesel, an alternative source of fuel applied in economic important areas. This study evaluates the fatty acid profiles and concentrations of three Brazilian seaweed species, Hypnea musciformis (Wulfen J.V. Lamouroux (Rhodophya, Sargassum cymosum C. Agardh (Heterokontophyta, and Ulva lactuca L. (Chlorophyta, comparing three extraction methods (Bligh & Dyer - B&D; AOAC Official Methods - AOM; and extraction with methanol and ultrasound - EMU and two transesterification methods (7% BF3 in methanol - BF3; and 5% HCl in methanol - HCl. The fatty acid contents of the three species of seaweeds were significantly different when extracted and transesterified by the different methods. Moreover, the best method for one species was not the same for the other species. The best extraction and transesterification methods for H. musciformis, S. cymosum and U. lactuca were, respectively, AOM-HCl, B&D-BF3 and B&D-BF3/B&D-HCl. These results point to a matrix effect and the method used for the analysis of the fatty acid content of different organisms should be selected carefully.

Blue and Green Light-Induced Phototropism in Arabidopsis thaliana and Lactuca sativa L. Seedlings 1

Science.gov (United States)

Steinitz, Benjamin; Ren, Zhangling; Poff, Kenneth L.

1985-01-01

Exposure time-response curves for blue and green light-induced phototropic bending in hypocotyls of Arabidopsis thaliana (L.) Heynh. and Lactuca sativa L. seedlings are presented. These seedlings show significant phototropic sensitivity up to 540 to 550 nanometers. Since wave-lengths longer than 560 nanometers do not induce phototropic bending, it is suggested that the response to 510 to 550 nanometers light is mediated by the specific blue light photoreceptor of phototropism. We advise care in the use of green `safelights' for studies of phototropism. PMID:16664021

Behaviour of technetium in marine algae

International Nuclear Information System (INIS)

Bonotto, S.; Kirchmann, R.; Van Baelen, J.; Hurtger, C.; Cogneau, M.; Van der Ben, D.; Verthe, C.; Bouquegneau, J.M.

1985-01-01

Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95m-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography

Introduced marine macroflora of Lebanon and its distribution on the Levantine coast

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G. BITAR

2017-03-01

Full Text Available The marine macroflora introduced into Lebanon was studied through an analysis of historical data and field studies carried out since 1991. A total of 29 introduced species have been listed: 3 Chromobionta, 13 Rhodobionta, 12 Chlorobionta and 1 Streptobionta. Among them, Caulerpa taxifolia var. distichophylla, Spatoglossum variabile and Womersleyella setacea are recorded for the first time from Lebanon. Among them, Asparagopsis taxiformis, C. taxifolia var. distichophylla, Cladophora patentiramea, Codium arabicum, Codium parvulum, Galaxaura rugosa, Halophila stipulacea, Hypnea cornuta, Laurencia cf. chondrioides, Lophocladia lallemandii, Stypopodium schimperi, Ulva lactuca and Womersleyella setacea are potentially invasive species, and several of them already occupy extensive stretches of the Lebanese coast. The distribution of species on the Levantine coast, their dynamics and the current status of their populations are discussed.

Behaviour of technetium in marine algae

International Nuclear Information System (INIS)

Bonotto, S.; Kirchmann, R.; Baelen, J. van; Hurtgen, C.; Cogneau, M.; Ben, D. van der; Verthe, C.; Bouquegneau, J.M.

1986-01-01

Uptake and distribution of technetium were studied in several green (Acetabularia acetabulum, Boergesenia forbesii, Ulva lactuca) and brown (Ascophyllum nodosum, Fucus serratus, Fucus spiralis and Fucus vesiculosus) marine algae. Technetium was supplied to the algae as Tc-95-pertechnetate. Under laboratory conditions, the algae were capable of accumulating technetium, with the exception, however, of Boergesenia, which showed concentration factors (C.F.) comprised between 0.28 and 0.71. The concentration of technetium-99 in Fucus spiralis, collected along the Belgian coast, was measured by a radiochemical procedure. The intracellular distribution of technetium was studied by differential centrifugation in Acetabularia and by the puncturing technique in Boergesenia. The chemical forms of technetium penetrated into the cells were investigated by selective chemical extractions, molecular sieving and thin layer chromatography. (author)

Influence of tetramethyl lead on the proplastids of plant cells. [Lactuca sativa L

Energy Technology Data Exchange (ETDEWEB)

Herich, R.; Bobak, M.

1974-01-01

The influence of tetramethyl lead upon the meristematic cells of the root tips of lettuce (Lactuca sativa L.) is dealt with in this article. The following phenomena have been observed: (1) differentiation of atypical proplastids; (2) gradual differentiation of tubular formations in the proplastids, the differentiating process is described in detail; (3) destruction of marginal membrane of the proplastid after the differentiation of these tubular formations together with disappearing of the individuality of the proplastid; (4) dislocation of the tubular formations from the plastid into the basic cytoplasm after destruction of the marginal membrane. In the cytoplasm the tubular formations are dispersed or persist in several groups. 8 references, 11 figures.

Analysis of expressed sequence tags from the Ulva prolifera (Chlorophyta)

Science.gov (United States)

Niu, Jianfeng; Hu, Haiyan; Hu, Songnian; Wang, Guangce; Peng, Guang; Sun, Song

2010-01-01

In 2008, a green tide broke out before the sailing competition of the 29th Olympic Games in Qingdao. The causative species was determined to be Enteromorpha prolifera ( Ulva prolifera O. F. Müller), a familiar green macroalga along the coastline of China. Rapid accumulation of a large biomass of floating U. prolifera prompted research on different aspects of this species. In this study, we constructed a nonnormalized cDNA library from the thalli of U. prolifera and acquired 10 072 high-quality expressed sequence tags (ESTs). These ESTs were assembled into 3 519 nonredundant gene groups, including 1 446 clusters and 2 073 singletons. After annotation with the nr database, a large number of genes were found to be related with chloroplast and ribosomal protein, GO functional classification showed 1 418 ESTs participated in photosynthesis and 1 359 ESTs were responsible for the generation of precursor metabolites and energy. In addition, rather comprehensive carbon fixation pathways were found in U. prolifera using KEGG. Some stress-related and signal transduction-related genes were also found in this study. All the evidences displayed that U. prolifera had substance and energy foundation for the intense photosynthesis and the rapid proliferation. Phylogenetic analysis of cytochrome c oxidase subunit I revealed that this green-tide causative species is most closely affiliated to Pseudendoclonium akinetum (Ulvophyceae).

Influence of lead upon the plant cell. [Lactuca sativa L

Energy Technology Data Exchange (ETDEWEB)

Sekerka, V; Bobak, M

1975-01-01

An attempt is made to study the influence of tetramethyl lead upon the mitotic activity of cells, structural changes of the chromosomes, upon the mitotic apparatus and the ultrastructure of the cells in lettuce (Lactuca sativa L.) Tetramethyl lead is an antidetonant additive to the gasoline of automobiles. The authors have found that the Pb ions are toxic for the plant cell, its toxicity increases with an increasing concentration and the prolonged time of action of the Pb solution. Tetramethyl lead influences the cell division causing especially different disturbances of the chromosomes and of the dividing figure during karykinesis and evoking damages of the submicroscopic structure of the plant cell. First of all, the following organels are damaged: the nucleus, the mitochondria, the Golgi apparatus, the endoplasmatic reticulum and the proplastids. A considerable number of formations similar to translosomes arises in the plant cells at the same time.

Efecto de rizobacterias promotoras de crecimiento vegetal solubilizadoras de fosfato en Lactuca sativa cultivar White Boston

Directory of Open Access Journals (Sweden)

Diana Beatriz Sanchez López

2014-07-01

Full Text Available Título en español: Efecto de rizobacterias promotoras de crecimiento vegetal solubilizadoras de fosfato en Lactuca sativa cultivar White Boston Título en ingles: Effect of plant growth promoting rhizobacteria phosate solubilizing  Lactuca sativa cultivar White Boston Resumen:  En las últimas décadas, la agricultura colombiana se ha visto afectada por la reducción de la productividad en las zonas hortícolas, el incremento de los costos de producción y la dependencia del uso de productos químicos, produciendo un daño irreversible al medio ambiente y la calidad de vida de productores y consumidores. El objetivo de investigación fue evaluar el efecto de rizobacterias promotoras del crecimiento  vegetal del género Pseudomonas sp. sobre Lactuca sativa cultivar White Boston como solubilizadoras de roca fosfórica. El estudio se realizó en el Centro de Investigación Tibaitatá (Corpoica ubicado en Mosquera (Cundinamarca-Colombia. Los resultados demostraron que las cepas tienen la capacidad intrínseca para solubilizar fuentes de fósforo de baja solubilidad como la roca fosfórica. La aplicación de inoculantes con base en las cepas: Pseudomonas fluorescens FR1, Pseudomonas sp., UVLO27 y Pseudomonas sp. LEAV18 arrojaron los mejores resultados. Las cepas Pseudomonas sp. FR2, UVLO27 y K35, tienen la capacidad de producir índoles y sideróforos. El experimento en invernadero evidenció que las cepas Pseudomonas fluorescens FR1, Pseudomonas sp. FR2 y UVLO27 incrementaron de manera significativa (P<0.05 la biomasa y el desarrollo de las plantas. El uso de rocas fosfóricas representa una alternativa económica y ecológica viable, en sistemas de agricultura sostenible.  Palabras claves: Pseudomonas sp., Biofertilizantes, Roca fosfórica, Fósforo, Índoles totales. Abstract:  In the last decades, Colombian agriculture has been affected by the reduction in productivity in horticultural areas, increase in production costs and the dependence

Physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata algae polysaccharide.

Science.gov (United States)

Shao, Ping; Ma, Huiling; Qiu, Qiang; Jing, Weiping

2016-11-01

The physical stability of R-(+)-Limonene emulsions stabilized by Ulva fasciata polysaccharide (UFP) was investigated in this study. Emulsion physical stability was evaluated under different polysaccharide concentrations (1%-5%, wt/wt) and pH values (3.0-11.0). The stability of R-(+)-Limonene emulsions was demonstrated by droplet size distribution, rheological properties, zeta potential and visual phase separation. R-(+)-Limonene emulsions displayed monomodal droplet size distributions, high absolute values of zeta potential and good storage stability when 3% (wt/wt) UFP was used. The rheological properties and stability of R-(+)-Limonene emulsions appeared to be dependent on polysaccharide concentration. The emulsion stability was impacted by pH. Higher zeta potential (-52.6mV) and smaller mean droplet diameter (2.45μm) were achieved in neutral liquid environment (pH 7.0). Extreme acidity caused the flocculation of emulsions, which was manifested as phase separation, while emulsions were quite stable in an alkaline environment. Through comparing the stabilities of emulsions stabilized by different emulsifiers (i.e. UFP, GA and Gelatin), the result suggested that UFP was the best emulsifying agent among them. Copyright © 2016 Elsevier B.V. All rights reserved.

Element uptake and physiological responses of Lactuca sativa upon co-exposures to tourmaline and dissolved humic acids.

Science.gov (United States)

Jia, Weili; Wang, Cuiping; Ma, Chuanxin; Wang, Jicheng; Sun, Hongwen

2018-03-27

Element migration and physiological response in Lactuca sativa upon co-exposure to tourmaline (T) and dissolved humic acids (DHAs) were investigated. Different fractions of DHA 1 and DHA 4 and three different doses of T were introduced into Hoagland's solution. The results indicated that T enhanced the contents of elements such as N and C, Si and Al in the roots and shoots. The correlation between TF values of Si and Al (R 2  = 0.7387) was higher than that of Si and Mn (R 2  = 0.4961) without the presence of DHAs. However, both DHA 1 and DHA 4 increased the correlation between Si and Mn, but decreased the one between Si and Al. CAT activities in T treatments were positively correlated to the contents of N and Al in the shoots, whose R 2 was 0.9994 and 0.9897, respectively. In the co-exposure of DHAs and tourmaline, DHA 4 exhibited more impacts on element uptake, CAT activities, as well as ABA contents in comparison with the presence of DHA 1 , regardless of the T exposure doses. These results suggested that DHAs have effects on mineral element behaviors and physiological response in Lactuca sativa upon exposure to tourmaline for the first time, which had great use in guiding soil remediation.

Isolation and culture of protoplast from leaves of Lactuca sativa

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Witool Chaipakdee

2007-07-01

Full Text Available Protoplasts were isolated from leaves of lettuce (Lactuca sativa L. seedlings after in vitro germination for 25, 30, 40 and 50 days. The leaves were stripped and incubated in various combinations of cellulase and pectinase. Protoplasts were cultured on MS medium containing various kinds and concentrations of plant growth regulators in different culture systems including liquid media, hanging, drop culture and solid media. Results revealed that the highest number of viable protoplasts, 14.1x105 cells per gram of fresh weight, was obtained from 30 day-old leaves of lettuce seedlings and isolated by using 2% cellulase in combination with 1% pectinase. Liquid MS medium supplemented with 0.5 mg/l NAA and 0.5 mg/l BA promoted the highest cell division up to 17.67%. First division of protoplasts was observed at 4 days after culture and microcolony formation occurred at the 4th week after culturing. Unfortunately, neither callus formation nor plantlet regeneration were obtained.

Biochemical evaluation of antioxidant activity and polysaccharides fractions in seaweeds

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A. Tariq

2015-01-01

Full Text Available In the present study ethanol and water extracts of 15 seaweeds, Dictyota dichotoma var. velutricata, Dictyota indica, Iyengaria stellata, Padina pavonia, Sargassum swartzii, Sargassum variegatum, Stoechospermum marginatum, Stokeyia indica, Jolyna laminarioides, Caulerpa taxifolia, Halimeda tuna, Ulva fasciata, Ulva lactuca, Solieria robusta, and Melanothamnus afaqhusainii, were evaluated for their antioxidant potential by ABTS or 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid, superoxide and total antioxidant capacity (TAC assays.  The activity was concentration dependent and the variation in antioxidant potential was also observed by different assays in both extracts.  Ethanol extract of D. dichotoma var. velutricata, D. indica and S. marginatum demonstrated highest activity by TAC assay.  The antioxidant potential in organic solvent fractions of seaweeds namely P. pavonia, S. swartzii, S. marginatum and M. afaqhusainii was also determined and chloroform fraction of all the four seaweeds showed highest activity by superoxide assay.  Antioxidant activity of extracted fractions of polysaccharides from S. indica, C. taxifolia and D. dichotoma var. velutricata was also evaluated by superoxide method.  Polysaccharide fractions of S. indica obtained from HCl (at 700C and room temperature and water extract demonstrated highest activity respectively.  All the polysaccharide fractions of C. taxifolia showed excellent activity except CaClF70°C. Polysaccharide fractions of D. dichotoma var. velutricata also exhibited very good activity.

Assess the environmental health status of macrophyte ecosystems using an oxidative stress biomarker. Case studies: The Gulf of Aqaba and the Lagoon of Venice

Science.gov (United States)

Wahsha, Mohammad; Juhmani, Abdul-Salam; Buosi, Alessandro; Sfriso, Andrea; Sfriso, Adriano

2017-04-01

Macrophytes play a fundamental role in structuring communities in aquatic environments. They contribute to maintaining the ecosystem services. Unfortunately, nowadays, they are threatened by different sources of pollution. The release of such potentially toxic elements (PTEs) to the environment may influence negatively the ecosystem health, which often limits and sometimes disqualifies the ecosystem biodiversity. Indeed, the increasing concentration and distribution of PTEs in the marine ecosystem by mismanagement of industrial activities, overuse of agrochemicals, and waste disposal are causing worldwide concern. The aim of this work is to describe the developing of an innovative early warning tool, based on the implementation of the lipid peroxidation oxidative stress biomarker for the assessment and monitoring of ecological status in response to PTEs in different marine environments. Six sites were selected along the Jordanian coastline of the Gulf of Aqaba and the lagoon of Venice in Italy according to different morphological, ecological conditions and anthropogenic impact. Our results indicated that the effect of PTEs causes oxidative stress to macrophytes; in particular: Ulva fasciata and Ulva lactuca collected from the lagoon of Venice and Gulf of Aqaba respectively. The oxidative stress by PTEs alters the biochemical processes, as it stimulates the generation of reactive oxygen species (ROS) and accordingly the oxidative degradation of lipids (LPO). The by-products of LPO, the organic compound malondialdehyde (MDA) is significantly correlated (pVenice, macrophytes, lipid peroxidation.

Hybridization rates between lettuce (Lactuca sativa) and its wild relative (L. serriola) under field conditions

OpenAIRE

D'Andrea, Luigi; Felber, François; Guadagnuolo, Roberto

2008-01-01

Hybridization and introgression between crops and wild relatives may have important evolutionary and ecological consequences such as gene swamping or increased invasiveness. In the present study, we investigated hybridization under field conditions between crop lettuce (Lactuca sativa) and its wild relative prickly lettuce (L. serriola), two cross-compatible, predominantly autogamous and insect pollinated species. In 2003 and 2004, we estimated the rates of hybridization between L. sativa and...

Interspecific somatic hybridization between lettuce (Lactuca sativa) and wild species L. virosa.

Science.gov (United States)

Matsumoto, E

1991-02-01

Somatic hybrids between cultivated lettuce (Lactuca sativa) and a wild species L. virosa were produced by protoplast electrofusion. Hybrid selection was based on inactivation of L. sativa with 20mM iodoacetamide for 15 min, and the inability of L. virosa protoplasts to divide in the culture conditions used. Protoplasts were cultured in agarose beads in a revised MS media. In all 71 calli were formed and 21 of them differentiated shoots on LS medium containing 0.1mg/l NAA and 0.2mg/l BA. Most regenerated plants exhibited intermediate morphology. These plants were confirmed as hybrids by isoenzyme analysis. The majority of somatic hybrids had 2n=4x=36 chromosomes, and had more vigorous growth than either parent. Hybrids had normal flower morphology, but all were sterile.

Biorefinery of the green seaweed Ulva lactuca to produce animal feed, chemicals and biofuels

NARCIS (Netherlands)

Bikker, Paul; Krimpen, van Marinus M.; Wikselaar, van Piet; Houweling-Tan, Bwee; Scaccia, Nazareno; Hal, van Jaap W.; Huijgen, Wouter J.J.; Cone, John W.; López-Contreras, Ana M.

2016-01-01

The growing world population demands an increase in animal protein production. Seaweed may be a valuable source of protein for animal feed. However, a biorefinery approach aimed at cascading valorisation of both protein and non-protein seaweed constituents is required to realise an economically

Formation of seed productivity in lettuce Lactuca sativa var. secalina L. depending on the form of inflorescence habitus

OpenAIRE

Н. В. Лещук

2009-01-01

It is explained the essence of the formation of seed production of lettuce Lactuca sativa var. secalina L. depending on the form of the inflorescence habitus, which formed during the different areas of plant nutrition. It is substantiated the mechanism of seed formation on different parts of the inflorescence of female plant with identification of it’s sowing quality. It is developed the agrotehnologcal measures aimed at improving the productivity of lettuce seed by overcoming its matrical he...

A multiresidue approach for the simultaneous quantification of antibiotics in macroalgae by ultra-high performance liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Leston, Sara; Freitas, Andreia; Rosa, João; Barbosa, Jorge; Lemos, Marco F L; Pardal, Miguel Ângelo; Ramos, Fernando

2016-10-15

Together with fish, algae reared in aquaculture systems have gained importance in the last years, for many purposes. Besides their use as biofilters of effluents, macroalgae's rich nutritional profiles have increased their inclusion in human diets but also in animal feeds as sources of fatty acids, especially important for the fish industry. Nonetheless, algae are continuously exposed to environmental contaminants including antibiotics and possess the ability for bioaccumulation of such compounds. Therefore, the present paper describes the development and validation of an ultra-high performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of antibiotics in the green macroalgae Ulva lactuca. This multi-residue method enables the determination of 38 compounds distributed between seven classes and was fully validated according to EU Decision 2002/657/EC. Copyright © 2016 Elsevier B.V. All rights reserved.

Antalya İli Batı Kıyıları (Lara – Kalkan'nın Ekonomik Amaçlı Deniz Algleri

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Furkan DURUCAN

2014-12-01

Abstract: This study has been carried out with seasonal samples in five stations in order to determine commercial seaweed in west coast of Antalya Province (Lara, Phaselis, Beymelek, Kaş, Kalkan. At the end of study, Rhodophyta (Corallina elongata Ellis & Solander, Corallina officinalis (Linnaeus, Gelidium capillaceum (S.G. Gmelin Kützing, Gelidium latifolium (Greville Bornet & Thuret, Jania adhaerens Lamouroux, Jania rubens (Linnaeus Lamouroux, Porphyra leucosticta Thuret, Heterokontophyta (Cystoseira compressa (Esper Gerloff et Nizamuddin, Cystoseira crinita Duby, Cystoseira elegans Sauvageau, Cystoseira spinosa Sauvageau, Cystoseira stricta (Montagne Sauvageau, Padina pavonica (Linnaeus Thivy, Sargassum vulgare C. Agardh, Chlorophyta (Enteromorpha intestinalis (L. Nees, Gayralia oxysperma (Kützing K.L. Vinogradova ex Scagel et al. ve Ulva lactuca Linnaeus. Species belong to the families have been determined as an important economic potential in this region. Key Words: Mediterranean, Antalya, seaweeds for economic purposing

Active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. / Embalagem ativa para alface americana (Lactuca sativa L. minimamente processada

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Fábio Yamashita

2010-09-01

Full Text Available The minimal processing of horticultural products endears the raw material and is convenient to the consumer due to the facility for preparing and consuming. The objective of this work was to develop an active packaging for fresh-cut iceberg lettuce (Lactuca sativa L. to increase its shelf life. Minimally processing methodology was defined and the product quality was determined by sensorial, physico-chemical and microbiological analysis. The lettuce tree was selected, trimmed, pre-washed, soaked in sanitized water (100ppm of active chlorine for 15 minutes and centrifuged. The lettuce leafs were packed in polypropylene pots with a sachet containing 1-methylcyclopropene (1-MCP and sealed with biodegradable starch film. Soon after the processing, the product was stored at 4oC for 12 days. Periodically samples were evaluated in terms of appearance and purchase intention, soluble solids and vitamin C contents, pH, texture, color, weight loss and total count of mesophilic and psicotrofic microorganisms, lactic bacteria, mould and yeast. Using 1-MCP in sachet format did not increase the lettuce shelf life but the minimal processing combined with packaging sealed with biodegradable film is practicable as the product showed good sensorial acceptance, low microbiological counts and shelf life of 5 days at 4oC.O processamento mínimo de produtos hortícolas agrega valor à matéria-prima e são convenientes ao consumidor, devido à facilidade de preparo e consumo. O objetivo do trabalho foi desenvolver uma embalagem ativa para alface americana (Lactuca sativa L. minimamente processada visando o aumento da vida útil. Foi definida uma metodologia de processamento mínimo e a qualidade do produto foi acompanhada através de avaliação sensorial, físico-química e microbiológica. As cabeças de alface foram desfolhadas, selecionadas, pré-lavadas, sanificadas (100 ppm de cloro ativo por 15 minutos e centrifugadas. As folhas foram acondicionadas em potes de

Allelopathic interactions between the opportunistic species Ulva prolifera and the native macroalga Gracilaria lichvoides.

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Dong Xu

Full Text Available Allelopathy, one type of direct plant competition, can be a potent mechanism through which plant communities are structured. The aim of this study was to determine whether allelopathic interactions occur between the opportunistic green tide-forming species Ulva prolifera and the native macroalga Gracilaria lichvoides, both of which were collected from the coastline of East China sea. In laboratory experiments, the presence of G. lichvoides at 1.25 g wet weight L(-1 significantly inhibited growth and photosynthesis of U. prolifera at concentrations of 1.25, 2.50, and 3.75 g wet weight L(-1 (p0.05. Culture medium experiments further confirmed that some allelochemicals may be released by both of the tested macroalgae, and these could account for the observed physiological inhibition of growth and photosynthesis. Moreover, the native macroalgae G. lichvoides was a stronger competitor than the opportunistic species U. prolifera. Collectively, the results of the present study represent a significant advance in exploring ecological questions about the effects of green tide blooms on the macroalgal community.

De novo sequencing and analysis of the Ulva linza transcriptome to discover putative mechanisms associated with its successful colonization of coastal ecosystems

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Zhang Xiaowen

2012-10-01

Full Text Available Abstract Background The green algal genus Ulva Linnaeus (Ulvaceae, Ulvales, Chlorophyta is well known for its wide distribution in marine, freshwater, and brackish environments throughout the world. The Ulva species are also highly tolerant of variations in salinity, temperature, and irradiance and are the main cause of green tides, which can have deleterious ecological effects. However, limited genomic information is currently available in this non-model and ecologically important species. Ulva linza is a species that inhabits bedrock in the mid to low intertidal zone, and it is a major contributor to biofouling. Here, we presented the global characterization of the U. linza transcriptome using the Roche GS FLX Titanium platform, with the aim of uncovering the genomic mechanisms underlying rapid and successful colonization of the coastal ecosystems. Results De novo assembly of 382,884 reads generated 13,426 contigs with an average length of 1,000 bases. Contiguous sequences were further assembled into 10,784 isotigs with an average length of 1,515 bases. A total of 304,101 reads were nominally identified by BLAST; 4,368 isotigs were functionally annotated with 13,550 GO terms, and 2,404 isotigs having enzyme commission (EC numbers were assigned to 262 KEGG pathways. When compared with four other full sequenced green algae, 3,457 unique isotigs were found in U. linza and 18 conserved in land plants. In addition, a specific photoprotective mechanism based on both LhcSR and PsbS proteins and a C4-like carbon-concentrating mechanism were found, which may help U. linza survive stress conditions. At least 19 transporters for essential inorganic nutrients (i.e., nitrogen, phosphorus, and sulphur were responsible for its ability to take up inorganic nutrients, and at least 25 eukaryotic cytochrome P450s, which is a higher number than that found in other algae, may be related to their strong allelopathy. Multi-origination of the stress related proteins

Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes.

Science.gov (United States)

Rauscher, Gilda; Simko, Ivan

2013-01-22

Lettuce (Lactuca sativa L.) is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L.) revealed that both the genetic heterozygosity (UHe = 0.56) and the number of loci per SSR (Na = 5.50) are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56). Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs) and RGC pseudogenes. Analysis of molecular variance (AMOVA) of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

Formation of seed productivity in lettuce Lactuca sativa var. secalina L. depending on the form of inflorescence habitus

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Н. В. Лещук

2009-12-01

Full Text Available It is explained the essence of the formation of seed production of lettuce Lactuca sativa var. secalina L. depending on the form of the inflorescence habitus, which formed during the different areas of plant nutrition. It is substantiated the mechanism of seed formation on different parts of the inflorescence of female plant with identification of it’s sowing quality. It is developed the agrotehnologcal measures aimed at improving the productivity of lettuce seed by overcoming its matrical heteroquality

Chromosomal study of lettuce and its allied species (Lactuca spp., Asteraceae) by means of karyotype analysis and fluorescence in situ hybridization.

Science.gov (United States)

Matoba, Hideyuki; Mizutani, Takayuki; Nagano, Katsuya; Hoshi, Yoshikazu; Uchiyama, Hiroshi

2007-12-01

In this study, in addition to the karyotype analysis, the chromosomal distributions of 5 S and 18 S rDNAs, and the Arabidopsis-type (T3AG3) telomeric sequences were detected by means of fluorescence in situ hybridization (FISH) to promote the information of chromosomal organization and evolution in the cultivated lettuce and its wild relatives, L. sativa, L. serriola, L. saligna and L. virosa. The karyotype analysis revealed the dissimilarity between L. virosa and the remaining species. In all four Lactuca species studied, one 5 S rDNA and two 18 S rDNA loci were detected. The simultaneous FISH of 5 S and 18 S rDNAs revealed that both rDNA loci of L. sativa, L. serriola and L. saligna were identical, however, that of L. virosa was different from the other species. These analyses indicate the closer relationships between L. sativa/L. serriola and L. saligna rather than L. virosa. Arabidopsis-type telomeric sequences were detected at both ends of their chromatids of all chromosomes not in the other regions. This observation suggests the lack of telomere-mediated chromosomal rearrangements among the Lactuca chromosomes.

Potentiating Effects of Lactuca sativa on Pentobarbital-Induced Sleep.

Science.gov (United States)

Ghorbani, Ahmad; Rakhshandeh, Hassan; Sadeghnia, Hamid Reza

2013-01-01

Traditionally, Lactuca sativa (lettuce) has been recommended for its hypnotic property. The present study was planned to investigate sleep-prolonging effect of this plant. The hydro-alcoholic extract (HAE) of lettuce and its water fraction (WF), ethyl acetate fraction (EAF), and n-butanol fraction (NBF) were administrated (IP) to mice 30 min before the pentobarbital injection. Moreover, both in-vivo and in-vitro toxicity of the extracts were determined. The quality of HAE and NBF was also evaluated using HPLC fingerprint. The HAE prolonged the pentobarbital-induced sleep duration at dose of 400 mg/Kg. The NBF was the only fraction which could increase the sleep duration and decrease sleep latency. The effects of NBF were comparable to those of induced by diazepam. The LD50-value for HAE was found to be 4.8 g/Kg. No neurotoxic effect was observed either by HAE or by its fractions in cultured PC12 neuron-like cells. The results suggest that lettuce potentiates pentobarbital hypnosis without major toxic effect. The main component(s) responsible for this effect is most likely to be non-polar agent(s) which found in NBF of this plant.

Structure, conformation in aqueous solution and antimicrobial activity of ulvan extracted from green seaweed Ulva reticulata.

Science.gov (United States)

Tran, Thi Thanh Van; Truong, Hai Bang; Tran, Nguyen Ha Vy; Quach, Thi Minh Thu; Nguyen, Thi Nu; Bui, Minh Ly; Yuguchi, Yoshiaki; Thanh, Thi Thu Thuy

2017-12-04

The aim of this study is to elucidate the structure and investigate the antimicrobial activity of an ulvan obtained by water extraction from green seaweed Ulva reticulata collected at Nha Trang sea of Vietnam by using IR, NMR, SEC-MALLS and SAXS methods. The ulvan is composed of rhamnose, galactose, xylose, manose and glucose (mole ratio Rha: Gal: Xyl: Man: Glu = 1:0.12:0.1:0.06:0.03), uronic acid (22.5%) and sulphate groups (17.6%). Chemically structural determination showed that the ulvan mainly composed of disaccharide [→4)β-D-GlcA(1→4)α-L-Rha3S-(1→]. The results from SAXS indicated that ulvan under study has a rod-like bulky chain conformation. Ulvan from U. reticulata showed high antimicrobial activity, with inhibition zone diameter of 20 mm against Enterobacter cloace and 18 mm against Escherichia coli.

Acute toxicity of live and decomposing green alga Ulva ( Enteromorpha) prolifera to abalone Haliotis discus hannai

Science.gov (United States)

Wang, Chao; Yu, Rencheng; Zhou, Mingjiang

2011-05-01

From 2007 to 2009, large-scale blooms of green algae (the so-called "green tides") occurred every summer in the Yellow Sea, China. In June 2008, huge amounts of floating green algae accumulated along the coast of Qingdao and led to mass mortality of cultured abalone and sea cucumber. However, the mechanism for the mass mortality of cultured animals remains undetermined. This study examined the toxic effects of Ulva ( Enteromorpha) prolifera, the causative species of green tides in the Yellow Sea during the last three years. The acute toxicity of fresh culture medium and decomposing algal effluent of U. prolifera to the cultured abalone Haliotis discus hannai were tested. It was found that both fresh culture medium and decomposing algal effluent had toxic effects to abalone, and decomposing algal effluent was more toxic than fresh culture medium. The acute toxicity of decomposing algal effluent could be attributed to the ammonia and sulfide presented in the effluent, as well as the hypoxia caused by the decomposition process.

Preliminary study on the responses of three marine algae, Ulva pertusa (Chlorophyta), Gelidium amansii (Rhodophyta) and Sargassum enerve (Phaeophyta), to nitrogen source and its availability

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Liu, Dongyan; Amy, Pickering; Sun, Jun

2004-04-01

An experiment was designed to select economically valuable macroalga species with high nutrient uptake rates. Such species cultured on a large scale could be a potential solution to eutrophication. Three macroalgae species, Ulva pertusa (Chlorophyta), Gelidium amansii (Rhodophyta) and Sargassum enerve (Phaeophyta), were chosen for the experiment because of their economic values and availability. Control and four nitrogen concentrations were achieved by adding NH{4/+} and NO{3/-}. The results indicate that the fresh weights of all species increase faster than that of control after 5 d culture. The fresh weight of Ulva pertusa increases fastest among the 3 species. However, different species show different responses to nitrogen source and its availability. They also show the advantage of using NH{4/+} than using NO{3/-}. U. pertusa grows best and shows higher capability of removing nitrogen at 200µmolL-1, but it has lower economical value. G. amansii has higher economical value but lower capability of removing nitrogen at 200 µmolL-1. The capability of nitrogen assimilation of S. enerve is higher than that of G. amansii at 200µmolL -1, but the former’s increase of fresh weight is lower than those of other two species. Then present preliminary study demonstrates that it is possible to use macroalgae as biofilters and further development of this approach could provide biologically valuable information on the source, fate, and transport of N in marine ecosystems. Caution is needed should we extrapolate these findings to natural environments.

Transfer and expression of the rabbit defensin NP-1 gene in lettuce (Lactuca sativa).

Science.gov (United States)

Song, D; Xiong, X; Tu, W F; Yao, W; Liang, H W; Chen, F J; He, Z Q

2017-01-23

Lettuce (Lactuca sativa L.) is an annual plant of the daisy family, Asteraceae, with high food and medicinal value. However, the crop is susceptible to several viruses that are transmitted by aphids and is highly vulnerable to post-harvest diseases, as well as insect and mammal pests and fungal and bacterial diseases. Here, the rabbit defensin gene NP-1 was transferred into lettuce by Agrobacterium-mediated transformation to obtain a broad-spectrum disease-resistant lettuce. Transgenic lettuce plants were selected and regenerated on selective media. The presence of the NP-1 gene in these plants was confirmed by western blot analyses. Resistance tests revealed native defensin NP-1 expression conferred partial resistance to Bacillus subtilis and Pseudomonas aeruginosa, which suggests new possibilities for lettuce disease resistance.

Fitotoxicidade e citogenotoxicidade da água e sedimento de córrego urbano em bioensaio com Lactuca sativa

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Luiz C. de A. Rodrigues

2013-10-01

Full Text Available Objetivou-se, com este trabalho, avaliar a influência espacial e temporal da fitotoxicidade e da citogenotoxicidade da água e do sedimento de córrego urbano quanto às características germinativas e de crescimento inicial de Lactuca sativa. Amostras de água e de sedimento foram coletadas em 5 pontos do Córrego do Pântano (Alfenas, Minas Gerais, no período de outubro de 2010 a julho de 2011 e as concentrações dos metais Cd, Pb e Zn foram quantificadas. Os ensaios de fitotoxicidade e de citogenotoxicidade foram realizados com as amostras de água e extratos aquosos dos sedimentos. Os parâmetros avaliados foram taxa de germinação, comprimento de raízes, biomassa fresca e seca, índice mitótico e a frequência de anormalidades cromossômicas. Constataram-se maiores concentrações de Cd e Pb nas amostras de água coletadas nos meses com a ocorrência de precipitações pluviométricas. Água e sedimento apresentaram efeito fitotóxico sobre germinação, biomassa fresca e seca de Lactuca sativa. O comprimento de raízes foi estimulado e apenas as amostras de água reduziram o índice mitótico. Evidenciou-se, também, variação temporal significativa relacionada com o regime pluviométrico apenas para o teste de fitotoxicidade.

Scientific rationale for cos lettuce growing technology Lactuca sativa var. longifolia L. in the Forest-Steppe of Ukraine

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Н. В. Лещук

2014-04-01

Full Text Available Scientifically validated items of growing technology disclosed for cos lettuce marketable products in the conditions of Forest-Steppe of Ukraine. Impact of environmental factors onto growth and development of Lactuca sativa var. longifolia L. plants. Sowing terms established for the seed of cos lettuce at field-seeded growing. Development parameters are quoted for plant productivity indices and marketable product indices for cos lettuce of national and foreign breeding. According to VCU characteristics a  typical model has been designed for the cos lettuce indices of suitability for dissemination in Ukraine.

Antioxidant Potential of ulva rigida c. Agardh Extract: Protection from Oxidative Stress Hypothyroidism

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S. TAŞ

2014-06-01

Full Text Available The purpose of this study was to evaluate the effects of Ulva rigida C. Agardh, one of the green algae, on and antioxidative system in the propylthiouracil (PTU-induced hypothyroid rats. Thirty-two rats randomly divided into four groups: control (C, control+U. rigida extract (C+UR, hypothyroid (H and hypothyroid+U. rigida extract (H+UR. U. rigida (2% was administered in drinking water for 5 weeks after the induction of hypothyroidism. Hypothyroid rats were under oxidative stress as reflected by icreased plasma and tissue malondialdehyde (MDA levels. U. rigida reduced serum total cholesterol and,- triglyceride levels and plasma and heart skeletal muscle, liver and,- kidney tissue MDA levels in the H+UR group. Serum total cholesterol and tissues MDA levels were reduced in the C+UR group. Whole blood glutathione peroxidase and erythrocyte superoxide dismutase activities were increased in the H+UR and C+UR groups compared with those of te respective control groups. Paraoxonase and arylesterase activities were lower in the H group and U. rigida increased paraoxonase and arylesterase activities in C+UR and H+UR groups. We conclude that hypothyroidism is associated with oxidative stress and, U. rigida extract might have a potential use as a protective antioxidant agent in hypothroidism.

Ethanol production from marine algal hydrolysates using Escherichia coli KO11.

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Kim, Nag-Jong; Li, Hui; Jung, Kwonsu; Chang, Ho Nam; Lee, Pyung Cheon

2011-08-01

Algae biomass is a potential raw material for the production of biofuels and other chemicals. In this study, biomass of the marine algae, Ulva lactuca, Gelidium amansii,Laminaria japonica, and Sargassum fulvellum, was treated with acid and commercially available hydrolytic enzymes. The hydrolysates contained glucose, mannose, galactose, and mannitol, among other sugars, at different ratios. The Laminaria japonica hydrolysate contained up to 30.5% mannitol and 6.98% glucose in the hydrolysate solids. Ethanogenic recombinant Escherichia coli KO11 was able to utilize both mannitol and glucose and produced 0.4g ethanol per g of carbohydrate when cultured in L. japonica hydrolysate supplemented with Luria-Bertani medium and hydrolytic enzymes. The strategy of acid hydrolysis followed by simultaneous enzyme treatment and inoculation with E. coli KO11 could be a viable strategy to produce ethanol from marine alga biomass. Copyright © 2011 Elsevier Ltd. All rights reserved.

Inhibitory effect of marine green algal extracts on germination of Lactuca sativa seeds.

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Choi, Jae-Suk; Choi, In Soon

2016-03-01

The allelopathic potential of nine green seaweed species was examined based on germination and seedling growth of lettuce (Lactuca sativa L.). Out of nine methanol extracts, Capsosiphon fulvescens and Monostroma nitidum extracts completely inhibited germination of L. sativa at 4 mg/filter paper after 24 hr of treatment. Water extracts of these seaweeds generally showed low anti-germination activities than methanol extracts. Of the nine water extracts, Enteromorpha linza extract completely inhibited L. sativa germination at 16 mg/filter paper after 24 hrs. To identify the primary active compounds, C. fulvescens. powder was successively fractionated according to polarity, and the main active agents against L. sativa were determined to be lipids (0.0% germination at 0.5 mg of lipids/paper disc). According to these results, extracts of C. fulvescens can be used to develop natural herbicidal agents and manage terrestrial weeds.

PENGARUH MACAM MULSA DAN DOSIS PUPUK KANDANG AYAM TERHADAP HASIL TANAMAN SELADA (Lactuca sativa, L.) VAR. NEW GRAND RAPID

OpenAIRE

Herumia, Mia; Haryono, Gembong; Susilowati, Yulia Eko

2017-01-01

The research on the effect of mulch kinds and the effect of chiken manure doses to the lettuce yield (Lactuca sativa, L.) var New Grand Rapid. Experiment conducted in August until October 2016. Location of experiment in Dukuhan, Sumber, Dukuh, Magelang. The latitude is 663 m. The soils regosol with pH 6,3. The research method used factorial experiment (3x4) arranged in a randomized complete block design with three blocks. The first factor is mulch kind, transparant plastic mulch, black silver...

Shifts in bacterial and archaeal community structures during the batch biomethanation of Ulva biomass under mesophilic conditions.

Science.gov (United States)

Kim, Jaai; Jung, Heejung; Lee, Changsoo

2014-10-01

Mesophilic biomethanation of Ulva biomass was performed in a batch bioreactor, and a high organic removal of 77% was obtained on the basis of chemical oxygen demand (COD) after a month of operation. The estimated methane yield was 0.43 ± 0.02 L CH4/g COD(removed) which is close to the theoretical methane potential. Transitions of bacterial and archaeal community structures, associated with process performance data, were investigated using a combination of molecular fingerprinting and biostatistical tools. During the operation, archaeal community structure had no significant changes while bacterial community structure shifted continuously and dynamically. The reactor completely stabilized volatile fatty acids (primarily acetate and propionate) accumulated from the acidogenesis phase, with Methanosaeta- and Methanolinea-related microbes respectively being the main aceticlastic and hydrogenotrophic methanogens. Methanolinea- and Syntrophobacter-related populations were likely the key members to form a syntrophic propionate-degrading consortium. A Methanolinea-related population was likely the dominant methane producer in the experimental reactor. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efficient and stable transformation of Lactuca sativa L. cv. Cisco (lettuce) plastids.

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Kanamoto, Hirosuke; Yamashita, Atsushi; Asao, Hiroshi; Okumura, Satoru; Takase, Hisabumi; Hattori, Masahira; Yokota, Akiho; Tomizawa, Ken-Ichi

2006-04-01

Transgenic plastids offer unique advantages in plant biotechnology, including high-level foreign protein expression. However, broad application of plastid genome engineering in biotechnology has been largely hampered by the lack of plastid transformation systems for major crops. Here we describe the development of a plastid transformation system for lettuce, Lactuca sativa L. cv. Cisco. The transforming DNA carries a spectinomycin-resistance gene (aadA) under the control of lettuce chloroplast regulatory expression elements, flanked by two adjacent lettuce plastid genome sequences allowing its targeted insertion between the rbcL and accD genes. On average, we obtained 1 transplastomic lettuce plant per bombardment. We show that lettuce leaf chloroplasts can express transgene-encoded GFP to approximately 36% of the total soluble protein. All transplastomic T0 plants were fertile and the T1 progeny uniformly showed stability of the transgene in the chloroplast genome. This system will open up new possibilities for the efficient production of edible vaccines, pharmaceuticals, and antibodies in plants.

Qualidade física, microbiológica e parasitológica de alfaces (Lactuca sativa de diferentes sistemas de cultivo Physical, microbiological and parasitological quality of lettuce (Lactuca sativa from different growing processes

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Ligia Regina R. de Santana

2006-06-01

Full Text Available A alface (Lactuca sativa é a hortaliça folhosa mais comercializada no Brasil. Seu baixo valor calórico a qualifica para diversas dietas, o que favorece o seu consumo sob a forma crua, possibilitando a ocorrência de enfermidades intestinais. O objetivo deste trabalho foi realizar uma avaliação física, microbiológica e parasitológica de amostras de alfaces, variedade crespa, provenientes dos sistemas de cultivo orgânico, tradicional e hidropônico, comercializadas nos principais supermercados da cidade de Salvador (BA, no período de setembro de 2003 a junho de 2004. As amostras do cultivo hidropônico apresentaram o menor peso total e da parte bio-comestível, diferindo significativamente (pThe lettuce (Lactuca sativa has economic importance to the people in Brazil. The aim of this study was to carry out a physical, microbiological and parasitological evaluations in the lettuce samples - crisp variety, according to organic, traditional and hydroponics growing processes, commercialized at the supermarkets of the City of Salvador, Bahia, Brazil, collected from September/2003 until June/2004. The hydroponics lettuce samples showed the lowest total and edible part weight; they were inserted into Extra rate quality standard, according to the current legislation, whereas the organic and traditional lettuce samples were inserted into First and Second rate quality standard, respectively. The lettuce samples, independently of the growing process, showed low hygienic conditions, indicated by the presence of parasites of animal or human origin, and high concentration of fecal coliforms; the organic lettuce samples showed the highest frequencies of enteroparasities and fecal coliforms concentration, followed by the traditional and hydroponics lettuce samples. Considering the obtained results, the importance of this kind of food in the transmission of enteroparasities is stressed, as well as the need of actions which improve the sanitary conditions

Role of Ethylene in Lactuca sativa cv ;Grand Rapids' Seed Germination.

Science.gov (United States)

Abeles, F B

1986-07-01

Promotion of thermoinhibited (30 degrees C) lettuce (Lactuca sativa cv ;Grand Rapids') seed germination by ethylene is similar to the action of the gas in other hormonal systems. Ethylene was more active than propylene and ethane was inactive. An inhibitor of ethylene production, aminoethoxy-vinylglycine, reduced ethylene evolution and germination. Inhibitors of ethylene action such as, 5-methyl-7-chloro-4-ethoxycarbonylmethoxy-2,1,3-benzothiadiazole, 2,5-norbornadiene, and silver thiosulfate inhibited germination and the effect was reversed by the addition of ethylene to the gas phase. The action of ethylene appears to be due to the promotion of radial cell expansion in the embryonic hypocotyl. The action of N6-benzyladenine and fusiccocin, which also overcome thermoinhibition, appears to be due to a promotion of hypocotyl elongation. None of the germination promoters studied appeared to function by lowering the mechanical resistance of the endosperm to embryonic growth. Data presented here are consistent with the view that ethylene plays a role in lettuce seed germination under thermoinhibited and normal conditions.

Internalization of Murine Norovirus 1 by Lactuca sativa during Irrigation ▿

Science.gov (United States)

Wei, Jie; Jin, Yan; Sims, Tom; Kniel, Kalmia E.

2011-01-01

Romaine lettuce (Lactuca sativa) was grown hydroponically or in soil and challenged with murine norovirus 1 (MNV) under two conditions: one mimicking a severe one-time contamination event and another mimicking a lower level of contamination occurring over time. In each condition, lettuce was challenged with MNV delivered at the roots. In the first case, contamination occurred on day one with 5 × 108 reverse transcriptase quantitative PCR (RT-qPCR) U/ml MNV in nutrient buffer, and irrigation water was replaced with virus-free buffer every day for another 4 days. In the second case, contamination with 5 × 105 RT-qPCR U/ml MNV (freshly prepared) occurred every day for 5 days. Virus had a tendency to adsorb to soil particles, with a small portion suspended in nutrient buffer; e.g., ∼8 log RT-qPCR U/g MNV was detected in soil during 5 days of challenge with virus inoculums of 5 × 108 RT-qPCR U/ml at day one, but sativa. PMID:21296944

Identification, genetic localization, and allelic diversity of selectively amplified microsatellite polymorphic loci in lettuce and wild relatives (Lactuca spp.).

Science.gov (United States)

Witsenboer, H; Michelmore, R W; Vogel, J

1997-12-01

Selectively amplified microsatellite polymorphic locus (SAMPL) analysis is a method of amplifying microsatellite loci using generic PCR primers. SAMPL analysis uses one AFLP primer in combination with a primer complementary to microsatellite sequences. SAMPL primers based on compound microsatellite sequences provided the clearest amplification patterns. We explored the potential of SAMPL analysis in lettuce to detect PCR-based codominant microsatellite markers. Fifty-eight SAMPLs were identified and placed on the genetic map. Seventeen were codominant. SAMPLs were dispersed with RFLP markers on 11 of the 12 main linkage groups in lettuce, indicating that they have a similar genomic distribution. Some but not all fragments amplified by SAMPL analysis were confirmed to contain microsatellite sequences by Southern hybridization. Forty-five cultivars of lettuce and five wild species of Lactuca were analyzed to determine the allelic diversity for codominant SAMPLs. From 3 to 11 putative alleles were found for each SAMPL; 2-6 alleles were found within Lactuca sativa and 1-3 alleles were found among the crisphead genotypes, the most genetically homogeneous plant type of L. sativa. This allelic diversity is greater than that found for RFLP markers. Numerous new alleles were observed in the wild species; however, there were frequent null alleles. Therefore, SAMPL analysis is more applicable to intraspecific than to interspecific comparisons. A phenetic analysis based on SAMPLs resulted in a dendrogram similar to those based on RFLP and AFLP markers.

Complete genome sequence of the biofilm-forming Curtobacterium sp. strain BH-2-1-1, isolated from lettuce (Lactuca sativa) originating from a conventional field in Norway.

Science.gov (United States)

Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

2016-12-01

Here, we present the 3,795,952 bp complete genome sequence of the biofilm-forming Curtobacterium sp. strain BH-2-1-1, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017580.

Dependence of UV effect on quality of light during raising of seedlings (Lactuca sativa L.)

International Nuclear Information System (INIS)

Bogenrieder, A.; Klein, R.

1978-01-01

Greenhouse seedlings of Lactuca sativa L. show a decreased rate of photosynthesis under normal outdoor light conditions due to the effect of UV-light. In this study, the relationship between the declining rate of photosynthesis and the amount of UV in the spectrum was investigated. The determination was made in climatized gas exchange chambers under Xenon arc lamps (XBO 2500 W, Osram). The amount of UV in the spectrum was varied by the use of different surface mirrors made by aluminium evaporation. A linear relationship between the amount of UV-light in the spectrum and the rate of decrease of photosynthesis was obtained with 12 hour radiation. The decrease in photosynthesis is less when the plants are raised under UV-light lamps. (orig.) [de

Enhancing methane production from U. lactuca using combined anaerobically digested sludge (ADS) and rumen fluid pre-treatment and the effect on the solubilization of microbial community structures.

Science.gov (United States)

Zou, Yu; Xu, Xiaochen; Li, Liang; Yang, Fenglin; Zhang, Shushen

2018-04-01

Methane production by the anaerobic digestion of seaweed is restricted by the slow degradation caused by the influence of the rigid algal cell wall. At the present time, there has been no study focusing on the anaerobic digestion of U. lactuca by co-fermentation and pre-treatment with rumen fluid. Rumen fluid can favor methane production from algal biomass by utilizing the diversity and quantity of bacterial and archaeal communities in the rumen fluid. This research presents a novel method based on combined ADS and rumen fluid pre-treatment to improve the production of methane from seaweed. Biochemical methane potential (BMP) tests were performed to investigate the biogas production using combined ADS and rumen fluid pre-treatment at varied inoculum ratios on the performance of methane production from U. lactuca biomass. Compared to the control (no rumen fluid pre-treatment), the highest BMP yields of U. lactuca increased from 3%, 27.5% and 39.5% to 31.1%, 73% and 85.6%, respectively, for three different types of treatment. Microbial community analysis revealed that the Methanobrevibacter species, known to accept electrons to form methane, were only detected when rumen fluid was added. Together with the significant increase in species of Methanoculleus, Methanospirillum and Methanosaeta, rumen fluid improved the fermentation and degradation of the microalgae biomass not only by pre-treatment to foster cell-wall degradation but also by relying on methane production within itself during anaerobic processes. Batch experiments further indicated that rumen fluid applied to the co-fermentation and pre-treatment could increase the economic value and hold promise for enhancing biogas production from different seaweed species. Copyright © 2017 Elsevier Ltd. All rights reserved.

Assessment of Dual Life Stage Antiplasmodial Activity of British Seaweeds

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Deniz Tasdemir

2013-10-01

Full Text Available Terrestrial plants have proven to be a prolific producer of clinically effective antimalarial drugs, but the antimalarial potential of seaweeds has been little explored. The main aim of this study was to assess the in vitro chemotherapeutical and prophylactic potential of the extracts of twenty-three seaweeds collected from the south coast of England against blood stage (BS and liver stage (LS Plasmodium parasites. The majority (14 of the extracts were active against BS of P. falciparum, with brown seaweeds Cystoseira tamariscifolia, C. baccata and the green seaweed Ulva lactuca being the most active (IC50s around 3 μg/mL. The extracts generally had high selectivity indices (>10. Eight seaweed extracts inhibited the growth of LS parasites of P. berghei without any obvious effect on the viability of the human hepatoma (Huh7 cells, and the highest potential was exerted by U. lactuca and red seaweeds Ceramium virgatum and Halopitys incurvus (IC50 values 14.9 to 28.8 μg/mL. The LS-active extracts inhibited one or more key enzymes of the malarial type-II fatty acid biosynthesis (FAS-II pathway, a drug target specific for LS. Except for the red seaweed Halopitys incurvus, all LS-active extracts showed dual activity versus both malarial intracellular stage parasites. This is the first report of LS antiplasmodial activity and dual stage inhibitory potential of seaweeds.

Evaluation of the contamination of marine algae (seaweed) from the St. Lawrence River and likely to be consumed by humans

Energy Technology Data Exchange (ETDEWEB)

Phaneuf, D.; Cote, I.; Dumas, P.; Ferron, L.A.; LeBlanc, A. [CHUQ, Sainte-Foy, Quebec (Canada). Centre de Toxicologie du Quebec

1999-02-01

The goal of the study was to assess the contamination of marine algae (seaweeds) growing in the St. Lawrence River estuary and Gulf of St. Lawrence and to evaluate the risks to human health from the consumption of these algae. Algae were collected by hand at low tide. A total of 10 sites on the north and south shores of the St. Lawrence as well as in Baie des Chaleurs were sampled. The most frequently collected species of algae were Fucus vesiculosus, Ascophyllum nodosum, Laminaria Longicruris, Palmaria palmata, Ulva lactuca, and Fucus distichus. Alga samples were analyzed for metals iodine, and organochlorines. A risk assessment was performed using risk factors. In general, concentrations in St. Lawrence algae were not very high. Consequently, health risks associated with these compounds in St. Lawrence algae were very low. Iodine concentration, on the other hand, could be of concern with regard to human health. Regular consumption of algae, especially of Laminaria sp., could result in levels of iodine sufficient to cause thyroid problems. For regular consumers, it would be preferable to choose species with low iodine concentrations, such as U. lactuca and P. palmata, in order to prevent potential problems. Furthermore, it would also be important to assess whether preparation for consumption or cooking affects the iodine content of algae. Algae consumption may also have beneficial health effects. Scientific literature has shown that it is a good source of fiber and vitamins, especially vitamin B{sub 12}.

A novel ether-linked phytol-containing digalactosylglycerolipid in the marine green alga, Ulva pertusa

Energy Technology Data Exchange (ETDEWEB)

Ishibashi, Yohei; Nagamatsu, Yusuke [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Miyamoto, Tomofumi [Graduate School of Pharmaceutical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582 (Japan); Matsunaga, Naoyuki; Okino, Nozomu; Yamaguchi, Kuniko [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Ito, Makoto, E-mail: makotoi@agr.kyushu-u.ac.jp [Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

2014-10-03

Highlights: • Alkaline-resistant galactolipid, AEGL, was found in marine algae. • The sugar moiety of AEGL is identical to that of digalactosyldiacylglycerol. • AEGL is the first identified glycolipid that possesses an ether-linked phytol. • AEGL is ubiquitously distributed in green, red and brown marine algae. - Abstract: Galactosylglycerolipids (GGLs) and chlorophyll are characteristic components of chloroplast in photosynthetic organisms. Although chlorophyll is anchored to the thylakoid membrane by phytol (tetramethylhexadecenol), this isoprenoid alcohol has never been found as a constituent of GGLs. We here described a novel GGL, in which phytol was linked to the glycerol backbone via an ether linkage. This unique GGL was identified as an Alkaline-resistant and Endogalactosylceramidase (EGALC)-sensitive GlycoLipid (AEGL) in the marine green alga, Ulva pertusa. EGALC is an enzyme that is specific to the R-Galα/β1-6Galβ1-structure of galactolipids. The structure of U. pertusa AEGL was determined following its purification to 1-O-phytyl-3-O-Galα1-6Galβ1-sn-glycerol by mass spectrometric and nuclear magnetic resonance analyses. AEGLs were ubiquitously distributed in not only green, but also red and brown marine algae; however, they were rarely detected in terrestrial plants, eukaryotic phytoplankton, or cyanobacteria.

A novel ether-linked phytol-containing digalactosylglycerolipid in the marine green alga, Ulva pertusa

International Nuclear Information System (INIS)

Ishibashi, Yohei; Nagamatsu, Yusuke; Miyamoto, Tomofumi; Matsunaga, Naoyuki; Okino, Nozomu; Yamaguchi, Kuniko; Ito, Makoto

2014-01-01

Highlights: • Alkaline-resistant galactolipid, AEGL, was found in marine algae. • The sugar moiety of AEGL is identical to that of digalactosyldiacylglycerol. • AEGL is the first identified glycolipid that possesses an ether-linked phytol. • AEGL is ubiquitously distributed in green, red and brown marine algae. - Abstract: Galactosylglycerolipids (GGLs) and chlorophyll are characteristic components of chloroplast in photosynthetic organisms. Although chlorophyll is anchored to the thylakoid membrane by phytol (tetramethylhexadecenol), this isoprenoid alcohol has never been found as a constituent of GGLs. We here described a novel GGL, in which phytol was linked to the glycerol backbone via an ether linkage. This unique GGL was identified as an Alkaline-resistant and Endogalactosylceramidase (EGALC)-sensitive GlycoLipid (AEGL) in the marine green alga, Ulva pertusa. EGALC is an enzyme that is specific to the R-Galα/β1-6Galβ1-structure of galactolipids. The structure of U. pertusa AEGL was determined following its purification to 1-O-phytyl-3-O-Galα1-6Galβ1-sn-glycerol by mass spectrometric and nuclear magnetic resonance analyses. AEGLs were ubiquitously distributed in not only green, but also red and brown marine algae; however, they were rarely detected in terrestrial plants, eukaryotic phytoplankton, or cyanobacteria

Large-sized seaweed monitoring based on MODIS

Science.gov (United States)

Ma, Long; Li, Ying; Lan, Guo-xin; Li, Chuan-long

2009-10-01

In recent years, large-sized seaweed, such as ulva lactuca, blooms frequently in coastal water in China, which threatens marine eco-environment. In order to take effective measures, it is important to make operational surveillance. A case of large-sized seaweed blooming (i.e. enteromorpha), occurred in June, 2008, in the sea near Qingdao city, is studied. Seaweed blooming is dynamically monitored using Moderate Resolution Imaging Spectroradiometer (MODIS). After analyzing imaging spectral characteristics of enteromorpha, MODIS band 1 and 2 are used to create a band ratio algorithm for detecting and mapping large-sized seaweed blooming. In addition, chlorophyll-α concentration is inversed based on an empirical model developed using MODIS. Chlorophyll-α concentration maps are derived using multitemporal MODIS data, and chlorophyll-α concentration change is analyzed. Results show that the presented methods are useful to get the dynamic distribution and the growth of large-sized seaweed, and can support contingency planning.

Halogenated auxins affect microtubules and root elongation in Lactuca sativa

Science.gov (United States)

Zhang, N.; Hasenstein, K. H.

2000-01-01

We studied the effect of 4,4,4-trifluoro-3-(indole-3-)butyric acid (TFIBA), a recently described root growth stimulator, and 5,6-dichloro-indole-3-acetic acid (DCIAA) on growth and microtubule (MT) organization in roots of Lactuca sativa L. DCIAA and indole-3-butyric acid (IBA) inhibited root elongation and depolymerized MTs in the cortex of the elongation zone, inhibited the elongation of stele cells, and promoted xylem maturation. Both auxins caused the plane of cell division to shift from anticlinal to periclinal. In contrast, TFIBA (100 micromolar) promoted elongation of primary roots by 40% and stimulated the elongation of lateral roots, even in the presence of IBA, the microtubular inhibitors oryzalin and taxol, or the auxin transport inhibitor naphthylphthalamic acid. However, TFIBA inhibited the formation of lateral root primordia. Immunostaining showed that TFIBA stabilized MTs orientation perpendicular to the root axis, doubled the cortical cell length, but delayed xylem maturation. The data indicate that the auxin-induced inhibition of elongation and swelling of roots results from reoriented phragmoplasts, the destabilization of MTs in elongating cells, and promotion of vessel formation. In contrast, TFIBA induced promotion of root elongation by enhancing cell length, prolonging transverse MT orientation, delaying cell and xylem maturation.

Production and characterization of cyanocobalamin-enriched lettuce (Lactuca sativa L.) grown using hydroponics.

Science.gov (United States)

Bito, Tomohiro; Ohishi, Noriharu; Hatanaka, Yuka; Takenaka, Shigeo; Nishihara, Eiji; Yabuta, Yukinori; Watanabe, Fumio

2013-04-24

When lettuces (Lactuca sativa L.) grown for 30 days in hydroponic culture were treated with various concentrations of cyanocobalamin for 24 h, its content in their leaves increased significantly from nondetectable to 164.6 ± 74.7 ng/g fresh weight. This finding indicated that consumption of only two or three of these fresh leaves is sufficient to meet the Recommended Dietary Allowance for adults of 2.4 μg/day. Analyses using a cobalamin-dependent Escherichia coli 215 bioautogram and LC/ESI-MS/MS demonstrated that the cyanocobalamin absorbed from the nutrient solutions by the leaves did not alter any other compounds such as coenzymes and inactive corrinoids. Gel filtration indicated that most (86%) of the cyanocobalamin in the leaves was recovered in the free cyanocobalamin fractions. These results indicated that cyanocobalamin-enriched lettuce leaves would be an excellent source of free cyanocobalamin, particularly for strict vegetarians or elderly people with food-bound cobalamin malabsorption.

Nanocomposite strategies for limiting medical and marine biofouling

Science.gov (United States)

Cooper, Scott Patrick

are likely caused by various rates of silicate hydrolysis, condensation, and hydrogen bonding to PVP. Viscosity of the sol plays little role in determining the diameter of the dried microspheres. An antibiotic, vancomycin, is successfully incorporated into these hybrid microspheres. Vancomycin is released for 5-7 days as measured by UV absorption. An in vitro assay against cultures of Staphylococcus aureus demonstrates that the drug remains effective for 4 days. Marine biofouling is addressed by imparting topography onto silica-reinforced poly(dimethylsiloxane) elastomeric (PDMSe) films. Swimming zoospores from the green alga Ulva are used as a model fouling organism. A bio-inspired topography deterred attachment of the zoospores by 70-80% over a 4-hr assay. Image analysis of the zoospores suggests that the topography may inhibit biofilm formation by disrupting the early-stage aggregation of spores on the surface. The attachment kinetics fit, with high correlation, equations used to describe that adsorption of bacteria to surfaces. This suggests the same physical phenomena drives the attachment of bacteria and swimming algal zoospores to solid surfaces.

Effects of culture conditions on the growth and reproduction of Gut Weed, Ulva intestinalis Linnaeus (Ulvales, Chlorophyta

Directory of Open Access Journals (Sweden)

Rapeeporn Ruangchuay

2012-11-01

Full Text Available In vitro cultivation of Gut Weed, Ulva intestinalis Linnaeus, was experimentally studied to support its near optimalfarming, with potential impact in Thailand on its direct use as human food or its co-cultures in shrimp farming.Germling clusters (2 weeks old and 7.50±2.98 mm long were seeded into 500 mL flasks and biomass growth rateoptimized with respect to the main controllable factors; seedling density, salinity, light intensity, and temperature. These factorswere assumed to each have an optimal value independent of the others, and the factors were optimized one at a time. Themaximum growth at three to four weeks of cultivation was obtained at the factor levels of 0.05 gL-1, 20 ppt, 80 mol photonm-2s-1 and 25°C. Early zoosporangia were obtained from 2nd to 4th weeks. The relative growth rate ranged from 9.47 to 22.18 %day-1, and only asexual reproduction of U. intestinalis was observed under these culture conditions.

Eutrophication and warming-driven green tides (Ulva rigida) are predicted to increase under future climate change scenarios.

Science.gov (United States)

Gao, Guang; Clare, Anthony S; Rose, Craig; Caldwell, Gary S

2017-01-15

The incidence and severity of extraordinary macroalgae blooms (green tides) are increasing. Here, climate change (ocean warming and acidification) impacts on life history and biochemical responses of a causative green tide species, Ulva rigida, were investigated under combinations of pH (7.95, 7.55, corresponding to lower and higher pCO 2 ), temperature (14, 18°C) and nitrate availability (6 and 150μmolL -1 ). The higher temperature accelerated the onset and magnitude of gamete settlement. Any two factor combination promoted germination and accelerated growth in young plants. The higher temperature increased reproduction, which increased further in combination with elevated pCO 2 or nitrate. Reproductive success was highest (64.4±5.1%) when the upper limits of all three variables were combined. Biochemically, more protein and lipid but less carbohydrate were synthesized under higher temperature and nitrate conditions. These results suggest that climate change may cause more severe green tides, particularly when eutrophication cannot be effectively controlled. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Jatropha curcas oil in Lactuca sativa root tip bioassays.

Science.gov (United States)

Andrade-Vieira, Larissa F; Botelho, Carolina M; Laviola, Bruno G; Palmieri, Marcel J; Praça-Fontes, Milene M

2014-03-01

Jatropha curcas L. (Euphorbiaceae) is important for biofuel production and as a feed ingredient for animal. However, the presence of phorbol esters in the oil and cake renders the seeds toxic. The toxicity of J. curcas oil is currently assessed by testing in animals, leading to their death. The identification of toxic and nontoxic improved varieties is important for the safe use of J. curcas seeds and byproducts to avoid their environmental toxicity. Hence, the aim of this study was to propose a short-term bioassay using a plant as a model to screen the toxicity of J. curcas oil without the need to sacrifice any animals. The toxicity of J. curcas oil was evident in germination, root elongation and chromosomal aberration tests in Lactuca sativa. It was demonstrated that J. curcas seeds contain natural compounds that exert phyto-, cyto- and genotoxic effects on lettuce, and that phorbol esters act as aneugenic agents, leading to the formation of sticky chromosomes and c-metaphase cells. In conclusion, the tests applied have shown reproducibility, which is important to verify the extent of detoxification and to determine toxic doses, thus reducing the numbers of animals that would be used for toxicity tests.

Comparative study of the germination of Ulva prolifera gametes on various substrates

Science.gov (United States)

Geng, Huixia; Yan, Tian; Zhou, Mingjiang; Liu, Qing

2015-09-01

Since 2007, massive green tides have occurred every summer in the southern Yellow Sea (YS), China. They have caused severe ecological consequences and huge economic losses. Ulva prolifera originated from Subei Shoal of the YS was confirmed as causative species of the green tides. The Porphyra yezoensis aquaculture rafts in the Subei Shoal have been highly suspected to be the "seed bed" of the green tides, because U. prolifera abundantly fouled the Porphyra yezoensis aquaculture facilities. Besides, various habitats of aquaculture ponds along the Jiangsu coastline and mudflat in the Subei Shoal were proposed to be possible sources of green tides. To understand the "seed" of the green tides in the southern YS and mitigate the original biomass of the green tide, various materials used as substrates for the germination of U. prolifera gametes were tested in this study. Culture experiments showed the following: 1) materials used in the P. yezoensis rafts (plastic, bamboo, jute rope, plastic rope, nylon netting, and plastic netting) displayed a significantly higher germination rate than those associated with mudflats and aquaculture ponds (mud, sand and rock); 2) plastics were the best substrates for the germination of U. prolifera gametes; 3) poor germination was found on old fronds of U. prolifera,, and rubber showed inhibitory effect on germination. The success in germination on P. yezoensis rafts related materials supports the notion that these mariculture structures may be involved in acting as a seed bed for green tide macroalgae. The lack of germination on rubber surfaces may suggest one way to limit the proliferation of early stages of U. prolifera.

Effects of partial desulfation on antioxidant and inhibition of DLD cancer cell of Ulva fasciata polysaccharide.

Science.gov (United States)

Shao, Ping; Pei, Yaping; Fang, Zhongxian; Sun, Peilong

2014-04-01

Ulva fasciata belonging to the family Ulvaceae, commonly known as 'sea lettuce', is an abundantly growing green seaweed in coastal seashore of South China. Three different molecular weight sulfated polysaccharides (UFP1, UFP2 and UFP3) were extracted and separated from U. fasciata by hot water extraction and ultrafiltration. The three native UFP fractions had partial desulfurization by solvolytic desulfation respectively and the effect of sulfate content on the exhibition of the antioxidant and anti-tumor capacities had been evaluated and compared. The results showed that each native polysaccharide (UFP1, UFP2, UFP3) with high sulfate content exhibited better antioxidant activities compared with the partial desulfated polysaccharides (DS-UFP1, DS-UFP2, DS-UFP3). Specifically, UFP2 with relatively high sulfate content, molecular weight and uronic acid content had consistently excellent antioxidant performances. However, UFP2 demonstrated the minimal inhibitory effects on growth of DLD intestinal cancer cells. Instead, DS-UFP3 with the lowest sulfate content but highest uronic acid content and molecular weight exhibited the best antitumor activity. Copyright © 2014 Elsevier B.V. All rights reserved.

A Bayesian analysis of gene flow from crops to their wild relatives: cultivated (Lactuca sativa L.) and prickly lettuce (L. serriola L.) and the recent expansion of L. serriola in Europe

NARCIS (Netherlands)

Uwimana, B; D'andrea, L.; Felber, F.; Hooftman, D.A.P.; den Nijs, H.C.M.; Smulders, M.J.M.; Visser, R.G.F.; van de Wiel, C.C.M.

2012-01-01

Interspecific gene flow can lead to the formation of hybrid populations that have a competitive advantage over the parental populations, even for hybrids from a cross between crops and wild relatives. Wild prickly lettuce (Lactuca serriola) has recently expanded in Europe and hybridization with the

Distributions of radionuclides among green alga (Ulva pertusa), sea water and marine sediment

International Nuclear Information System (INIS)

Nakamura, Ryoichi; Suzuki, Yuzuru; Ueda, Taishi

1976-01-01

Distributions of radionuclides ( 60 Co, 137 Cs, 95 Zr- 95 Nb and 106 Ru- 106 Rh) among green alga (Ulva pertusa), sea water and marine sediment were examined by radioisotope tracer experiment in order to estimate the influence of sediment on the accumulation of radionuclides by the alga. By the application of the compartment model to the experimental results, exponential formulas of distributions were obtained. Through comparison of the transfer coefficients of radionuclides calculated from the exponential formulas, the influence of the sediment on the accumulation of the radionuclides by the green alga was determined to be the largest for 60 Co, followed by 95 Zr,- 95 Nb, 106 Ru- 106 Rh and 137 Cs in this order. The activity ratios of 95 Zr- 95 Nb and 106 Ru- 106 Rh calculated from the transfer coefficients are larger for the alga than for the sediment, inversely those of 60 Co and 137 Cs show higher values for the sediment than for the alga. Especially, in the case of 60 Co, the activity ratio for the sediment is approximately 20 times greater than that for the alga. Biological half lives in green alga estimated from the transfer coefficients were 10 days for 60 Co, 7 days for 137 Cs, 26 days for 95 Zr- 95 Nb and 24 days for 95 Zr- 95 Nb and 24 days for 106 Ru- 106 Rh. (auth.)

Infectivity and pathogenicity of the oomycete Aphanomyces invadans in Atlantic menhaden Brevoortia tyrannus

Science.gov (United States)

Kiryu, Y.; Shields, J.D.; Vogelbein, W.K.; Kator, H.; Blazer, V.S.

2003-01-01

Atlantic menhaden Brevoortia tyrannus develop characteristic skin ulcers in response to infection by the oomycete Aphanomyces invadans. To investigate pathogenicity, we conducted a dose response study. Juvenile menhaden were inoculated subcutaneously with 0, 1, 5, 10, 100, and 500 secondary zoospores per fish and monitored for 37 d post-injection (p.i.). Survival rates declined with increasing zoospore dose, with significantly different survivorship curves for the different doses. Moribund and dead fish exhibited characteristic ulcerous lesions at the injection site starting at 13 d p.i. None of the sham-injected control fish (0 zoospore treatment) died. The LD50 (lethal dose killing 50% of exposed menhaden) for inoculated fish was estimated at 9.7 zoospores; however, some fish receiving an estimated single zoospore developed infections that resulted in death. Menhaden were also challenged by aqueous exposure and confirmed that A. invadans was highly pathogenic by this more environmentally realistic route. Fish that were acclimated to culture conditions for 30 d, and presumably free of skin damage, then aqueously exposed to 100 zoospores ml-1, exhibited 14% lesion prevalence with 11% mortality. Net-handled fish that were similarly infected had a significantly higher lesion prevalence (64%) and mortality (64%). Control fish developed no lesions and did not die. Scanning electron microscopy of fish skin indicated that zoospores adhered to intact epidermis, germinated and penetrated the epithelium with a germ tube. Our results indicate that A. invadans is a primary pathogen of menhaden and is able to cause disease at very low zoospore concentrations.

Pb low doses induced genotoxicity in Lactuca sativa plants.

Science.gov (United States)

Silva, S; Silva, P; Oliveira, H; Gaivão, I; Matos, M; Pinto-Carnide, O; Santos, C

2017-03-01

Soil and water contamination by lead (Pb) remains a topic of great concern, particularly regarding crop production. The admissible Pb values in irrigation water in several countries range from ≈0.1 to ≈5 mg L -1 . In order to evaluate putative effects of Pb within legal doses on crops growth, we exposed Lactuca sativa seeds and seedlings to increasing doses of Pb(NO 3 ) 2 up to 20 mg L -1 . The OECD parameter seed germination and seedling/plant growth were not affected by any of the Pb-concentrations used. However, for doses higher than 5 mg L -1 significant DNA damage was detected: Comet assay detected DNA fragmentation at ≥ 5 mg L -1 and presence of micronuclei (MN) were detected for 20 mg L -1 . Also, cell cycle impairment was observed for doses as low as 0.05 mg L -1 and 0.5 mg L -1 (mostly G 2 arrest). Our data show that for the low doses of Pb used, the OECD endpoints were not able to detect toxicity, while more sensitive endpoints (related with DNA damage and mitotic/interphase disorders) identified genotoxic and cytostatic effects. Furthermore, the nature of the genotoxic effect was dependent on the concentration. Finally, we recommend that MN test and the comet assay should be included as sensitive endpoints in (eco)toxicological assays. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Genomic structure and evolution of the mating type locus in the green seaweed Ulva partita.

Science.gov (United States)

Yamazaki, Tomokazu; Ichihara, Kensuke; Suzuki, Ryogo; Oshima, Kenshiro; Miyamura, Shinichi; Kuwano, Kazuyoshi; Toyoda, Atsushi; Suzuki, Yutaka; Sugano, Sumio; Hattori, Masahira; Kawano, Shigeyuki

2017-09-15

The evolution of sex chromosomes and mating loci in organisms with UV systems of sex/mating type determination in haploid phases via genes on UV chromosomes is not well understood. We report the structure of the mating type (MT) locus and its evolutionary history in the green seaweed Ulva partita, which is a multicellular organism with an isomorphic haploid-diploid life cycle and mating type determination in the haploid phase. Comprehensive comparison of a total of 12.0 and 16.6 Gb of genomic next-generation sequencing data for mt - and mt + strains identified highly rearranged MT loci of 1.0 and 1.5 Mb in size and containing 46 and 67 genes, respectively, including 23 gametologs. Molecular evolutionary analyses suggested that the MT loci diverged over a prolonged period in the individual mating types after their establishment in an ancestor. A gene encoding an RWP-RK domain-containing protein was found in the mt - MT locus but was not an ortholog of the chlorophycean mating type determination gene MID. Taken together, our results suggest that the genomic structure and its evolutionary history in the U. partita MT locus are similar to those on other UV chromosomes and that the MT locus genes are quite different from those of Chlorophyceae.

Influences of marine sediment on the accumulation of radionuclides by green alga (Ulva pertusa)

International Nuclear Information System (INIS)

Nakamura, Ryoichi; Suzuki, Yuzuru; Ueda, Taiji

1975-01-01

Distribution of radionuclides ( 60 Co, 137 Cs, 95 Zr- 95 Nb and 106 Ru- 106 Rh) among green alga (Ulva pertusa), sea water and marine sediment were examined by radioisotope tracer experiment in order to estimate the influence of sediment on the accumulation of radionuclides by the alga. By the application of the compartment model to the experimental results, exponential formulas of distributions were obtained. Through comparison of the transfer coefficients of radionuclides calculated from the exponential formulas, the influence of the sediment on the accumulation of the radionuclides by the green alga was determined to be the largest for 60 Co, followed by 95 Zr- 95 Nb, 106 Ru- 106 Rh and 137 Cs in this order. The activity ratios of 95 Zr- 95 Nb and 106 Ru- 106 Rh calculated from the transfer coefficients are larger for the alga than for the sediment, inversely those of 60 Co and 137 Cs show higher values for the sediment than for the alga. Especially, in the case of 60 Co, the activity ratio for the sediment is approximately 20 times greater than that for the alga. Biological half lives in green alga estimated from the transfer coefficients were 10 days for 60 Co, 7 days for 137 Cs, 26 days for 95 Zr- 95 Nb and 24 days for 106 Ru- 106 Rh. (auth.)

The effect of UV on photosynthesis and growth in dependence of mineral nutrition (Lactuca sativa L. and Rumex alpinus L.)

International Nuclear Information System (INIS)

Bogenrieder, A.; Doute, Y.

1982-01-01

A clear increase in relative sensitivity of photosynthesis to UV-B occurs with increasing mineral concentration. As expected the chlorophyll content (a + b) per leaf area of control plants initially also increases (as can easily be noticed visualy). It remains, however, the same for the third to the highest concentration. The sensitivity of Rumex alpinus is higher but less influenced by mineral supply. In case of long term experiments, however, the relative differences between control and irradiated plants decreased clearly with increasing mineral supply. In Lactuca sativa, this is the opposite effect to the situation with short term irradiation. (orig./AJ)

Direct and indirect effects of high pCO2 on algal grazing by coral reef herbivores from the Gulf of Aqaba (Red Sea)

Science.gov (United States)

Borell, E. M.; Steinke, M.; Fine, M.

2013-12-01

Grazing on marine macroalgae is a key structuring process for coral reef communities. However, ocean acidification from rising atmospheric CO2 concentrations is predicted to adversely affect many marine animals, while seaweed communities may benefit and prosper. We tested how exposure to different pCO2 (400, 1,800 and 4,000 μatm) may affect grazing on the green alga Ulva lactuca by herbivorous fish and sea urchins from the coral reefs in the northern Gulf of Aqaba (Red Sea), either directly, by changing herbivore behaviour, or indirectly via changes in algal palatability. We also determined the effects of pCO2 on algal tissue concentrations of protein and the grazing-deterrent secondary metabolite dimethylsulfoniopropionate (DMSP). Grazing preferences and overall consumption were tested in a series of multiple-choice feeding experiments in the laboratory and in situ following exposure for 14 d (algae) and 28 d (herbivores). 4,000 μatm had a significant effect on the biochemical composition and palatability of U. lactuca. No effects were observed at 1,800 relative to 400 μatm (control). Exposure of U. lactuca to 4,000 μatm resulted in a significant decrease in protein and increase in DMSP concentration. This coincided with a reduced preference for these algae by the sea urchin Tripneustes gratilla and different herbivorous fish species in situ (Acanthuridae, Siganidae and Pomacanthidae). No feeding preferences were observed for the rabbitfish Siganus rivulatus under laboratory conditions. Exposure to elevated pCO2 had no direct effect on the overall algal consumption by T. gratilla and S. rivulatus. Our results show that CO2 has the potential to alter algal palatability to different herbivores which could have important implications for algal abundance and coral community structure. The fact that pCO2 effects were observed only at a pCO2 of 4,000 μatm, however, indicates that algal-grazer interactions may be resistant to predicted pCO2 concentrations in the

Application of destructive neutron activation analysis for determination of microelements in Zostera marina and Ulva lactuca

International Nuclear Information System (INIS)

Dam'yanova, A.; Lazarova, M.; Dechev, G.

1981-01-01

The content of microelements has been determined in two algal species from the Bulgarian Black Sea coast by neutron activation analysis. The disturbing effects of the main components 24 Na, 42 K and 32 P were eliminated by radiochemical separation. The results obtained for Fe, Co, Cr, Cd, Se, Zn, Ce, Sc, Rb, Au, Sm, As, Cu, Mn, Sb, and Hg are presented in ppm

Allelopathic effect of Raphanus sativus on Urochloa decumbens and Lactuca sativa = Efeito alelopático de Raphanus sativus em Urochloa decumbens e Lactuca sativa

Directory of Open Access Journals (Sweden)

Rafael Navas

2016-10-01

Full Text Available The aim of this study was to evaluate the allelopathic potential of an extract from the leaves and roots of Raphanus sativus, on the species Urochloa decumbens and Lactuca sativa L. To obtain the extract, the leaves and roots of R. sativus were used separately, crushed at a proportion of 200 g of leaves to 1 L of water to give a crude aqueous extract (100%. Dilutions of 60%, 40% and 20%, and the control were produced from this extract. Seeds of U. decumbens and L. sativa were evenly distributed over two sheets of germitest paper, with four replications of 40 seeds each. Germination was evaluated at 7 and 14 days after sowing, together with the germination speed index (GSI, length of the shoots and roots, and dry weight. The design was completely randomised, and the values submitted to analysis of variance by F-test and regression analysis. The leaf extract gave a reduction in the germination of L. sativa at all tested doses. With application of the root extract, an increase was seen in germination, in the GSI and length of the radicle in U. decumbens at doses of from 40%. Moreover, with application of the leaf extract, the length of the shoot and radicle were also greater, irrespective of the dose applied. There was no effect from the treatments on the dry mass of the species. = Objetivou-se com este trabalho avaliar o potencial alelopático de extrato de folhas e raízes de Raphanus sativus, nas espécies Urochloa decumbens e Lactuca sativa L. Para obtenção do extrato, foram utilizadas separadamente folhas e raízes de R. sativus, trituradas na proporção de 200 g de folhas para 1 L de água, resultando no extrato aquoso bruto (100%. A partir desse extrato, foram realizadas as diluições de 60%, 40% e 20% e testemunha. Sementes de U. decumbens e L. sativa foram distribuídas uniformemente sobre duas folhas de papel germitest, com quatro repetições, com 40 sementes cada. As avaliações de germinação foram realizadas aos 7 e aos 14 dias

Phyotoxicity of diesel soil contamination on the germination of Lactuca sativa and Ipomoea batatas.

Science.gov (United States)

Fatokun, Kayode; Lewu, Francis Bayo; Zharare, Godfrey Elijah

2015-11-01

Phytotoxic effect of diesel contaminated soil on germination rate of Lactuca sativa and Ipomoea batatas, at two concentrations ranges (0-6ml and 0-30ml), were investigated and compared. Diesel soil contamination was simulated and soil samples were taken from contaminated soil at 1, 5,10, 15, 25, 50, 75 and 100 days should be after planting. The result showed that in both plant species, diesel inhibited germination in a concentration dependent manner, Also, the influence of diesel contamination diminished with increased time duration; suggesting possible reduction in diesel toxicity over time. However, germination of lettuce was significant and negatively correlated (r2 = -0.941) with diesel contamination as compared to sweet potato (r2 = -0.638).Critical concentration of diesel in relation to seed germination of L. sativa was lower than vegetative germination of I. batatas, indicating that germination of I. batatas was less sensitive to diesel contamination as compared to L. sativa.

Studying the effects of different levels of salinity which caused by NaCl on early growth and germination of Lactuca Sativa L. seedling

OpenAIRE

KESHAVARZI MOHAMMAD HOSEIN BIJEH

2012-01-01

Soil salinity is one of the most important constraints that limit crop production in arid and semi arid regions. Seed germination is a critical stage in the history of plants and salt tolerance during germination is crucial for the establishment of plants that grow in saline soils. This research was carried out in order to test the effects of different salinity levels on germination and early growth of lettuce (Lactuca Sativa L.). The experiment was carried out using completely randomized des...

Use of cross-flow membrane filtration in a recirculating hydroponic system to suppress root disease in pepper caused by Pythium myriotylum.

Science.gov (United States)

Schuerger, Andrew C; Hammer, William

2009-05-01

Zoosporic pathogens in the genera Pythium and Phytophthora cause extensive root disease epiphytotics in recirculating hydroponic vegetable-production greenhouses. Zoospore cysts of Pythium myriotylum Drechsler were used to evaluate the effectiveness of cross-flow membrane filters to control pythiaceous pathogens in recirculating hydroponic systems. Four membrane filter brands (Honeycomb, Polypure, Polymate, and Absolife) were tested alone or in combination to determine which filters would effectively remove infective propagules of P. myriotylum from solutions and reduce disease incidence and severity. Zoospore cysts of P. myriotylum generally measured 8 to 10 microm, and it was hypothesized that filters with pore-sizespepper plants from root infection. Single-filter assays with Honeycomb and Polypure brands removed 85 to 95% of zoospore cysts when pore sizes were rated at 1, 5, 10, 20, or 30 microm. Single-filter assays of Polymate and Absolife brands were more effective, exhibiting apparently 100% removal of zoospore cysts from nutrient solutions on filters rated at 1 to 10 microm. However, plant bioassays with Honeycomb and Polymate single filters failed to give long-term protection of pepper plants. Double-filter assays with 1- and 0.5-microm Polymate filters significantly increased the protection of pepper plants grown in nutrient film technique systems but, eventually, root disease and plant wilt could be observed. Insect transmissions by shore flies were not factors in disease development. Scanning electron microscopy images of zoospore cysts entrapped on Polymate filters revealed zoospore cysts that were either fully encysted, partially encysted, or of unusually small size (3 microm in diameter). It was concluded that either the atypically small or pliable pleomorphic zoospore cysts were able to penetrate filter membranes that theoretically should have captured them.

Complete genome sequence of the biofilm-forming Microbacterium sp. strain BH-3-3-3, isolated from conventional field-grown lettuce (Lactuca sativa) in Norway.

Science.gov (United States)

Dees, Merete Wiken; Brurberg, May Bente; Lysøe, Erik

2017-03-01

The genus Microbacterium contains bacteria that are ubiquitously distributed in various environments and includes plant-associated bacteria that are able to colonize tissue of agricultural crop plants. Here, we report the 3,508,491 bp complete genome sequence of Microbacterium sp. strain BH-3-3-3, isolated from conventionally grown lettuce ( Lactuca sativa ) from a field in Vestfold, Norway. The nucleotide sequence of this genome was deposited into NCBI GenBank under the accession CP017674.

Ecotoxicological impact of two soil remediation treatments in Lactuca sativa seeds.

Science.gov (United States)

Rede, Diana; Santos, Lúcia H M L M; Ramos, Sandra; Oliva-Teles, Filipe; Antão, Cristina; Sousa, Susana R; Delerue-Matos, Cristina

2016-09-01

Pharmaceuticals have been identified as environmental emerging pollutants and are present in different compartments, including soils. Chemical remediation showed to be a good and suitable approach for soil remediation, though the knowledge in their impact for terrestrial organisms is still limited. Therefore, in this work, two different chemical remediation treatments (Fenton oxidation and nanoremediation) were applied to a soil contaminated with an environmental representative concentration of ibuprofen (3 ng g(-1)). The phytotoxic impact of a traditional soil remediation treatment (Fenton oxidation) and of a new and more sustainable approach for soil remediation (nanoremediation using green nano-scale zero-valent iron nanoparticles (nZVIs)) was evaluated in Lactuca sativa seeds. Percentage of seed germination, root elongation, shoot length and leaf length were considered as endpoints to assess the possible acute phytotoxicity of the soil remediation treatments as well as of the ibuprofen contaminated soil. Both chemical remediation treatments showed to have a negative impact in the germination and development of lettuce seeds, exhibiting a reduction up to 45% in the percentage of seed germination and a decrease around 80% in root elongation comparatively to the contaminated soil. These results indicate that chemical soil remediation treatments could be more prejudicial for terrestrial organisms than contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Jatropha curcas oil in Lactuca sativa root tip bioassays

Directory of Open Access Journals (Sweden)

LARISSA F. ANDRADE-VIEIRA

2014-03-01

Full Text Available Jatropha curcas L. (Euphorbiaceae is important for biofuel production and as a feed ingredient for animal. However, the presence of phorbol esters in the oil and cake renders the seeds toxic. The toxicity of J. curcas oil is currently assessed by testing in animals, leading to their death. The identification of toxic and nontoxic improved varieties is important for the safe use of J. curcas seeds and byproducts to avoid their environmental toxicity. Hence, the aim of this study was to propose a short-term bioassay using a plant as a model to screen the toxicity of J. curcas oil without the need to sacrifice any animals. The toxicity of J. curcas oil was evident in germination, root elongation and chromosomal aberration tests in Lactuca sativa. It was demonstrated that J. curcas seeds contain natural compounds that exert phyto-, cyto- and genotoxic effects on lettuce, and that phorbol esters act as aneugenic agents, leading to the formation of sticky chromosomes and c-metaphase cells. In conclusion, the tests applied have shown reproducibility, which is important to verify the extent of detoxification and to determine toxic doses, thus reducing the numbers of animals that would be used for toxicity tests.

Quantitative trait loci associated with seed and seedling traits in Lactuca.

Science.gov (United States)

Argyris, Jason; Truco, María José; Ochoa, Oswaldo; Knapp, Steven J; Still, David W; Lenssen, Ger M; Schut, Johan W; Michelmore, Richard W; Bradford, Kent J

2005-11-01

Seed and seedling traits related to germination and stand establishment are important in the production of cultivated lettuce (Lactuca sativa L.). Six seed and seedling traits segregating in a L. sativa cv. Salinas x L. serriola recombinant inbred line population consisting of 103 F8 families revealed a total of 17 significant quantitative trait loci (QTL) resulting from three seed production environments. Significant QTL were identified for germination in darkness, germination at 25 and 35 degrees C, median maximum temperature of germination, hypocotyl length at 72 h post-imbibition, and plant (seedling) quality. Some QTL for germination and early seedling growth characteristics were co-located, suggestive of pleiotropic loci regulating these traits. A single QTL (Htg6.1) described 25 and 23% of the total phenotypic variation for high temperature germination in California- and Netherlands-grown populations, respectively, and was significant between 33 and 37 degrees C. Additionally, Htg6.1 showed significant epistatic interactions with other Htg QTL and a consistent effect across all the three seed production environments. L. serriola alleles increased germination at these QTL. The estimate of narrow-sense heritability (h2) of Htg6.1 was 0.84, indicating potential for L. serriola as a source of germination thermotolerance for lettuce introgression programs.

Assessment of genetic diversity in lettuce (Lactuca sativa L.) germplasm using RAPD markers.

Science.gov (United States)

Sharma, Shubhangi; Kumar, Pankaj; Gambhir, Geetika; Kumar, Ramesh; Srivastava, D K

2018-01-01

The importance of germplasm characterization is an important link between the conservation and utilization of plant genetic resources in various breeding programmes. In the present study, genetic variability and relationships among 25 Lactuca sativa L. genotypes were tested using random amplified polymorphic DNA (RAPD) molecular markers. A total of 45 random decamer oligonucleotide primers were examined to generate RAPD profiles, out of these reproducible patterns were obtained with 22 primers. A total of 87 amplicon were obtained, out of which all were polymorphic and 7 were unique bands. The level of polymorphism across genotypes was 100% as revealed by RAPD. Genetic similarity matrix, based on Jaccard's coefficients ranged from 13.7 to 84.10% indicating a wide genetic base. Dendrogram was constructed by unweighted pair group method with arithmetic averages method. RAPD technology could be useful for identification of different accessions as well as assessing the genetic similarity among different genotypes of lettuce. The study reveals the limited genetic base and the needs to diversify using new sources from the germplasm.

Differential Responses of Two Lactuca sativa Varieties to Bicarbonate-Induced Iron Deficiency

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Mohamed Chebbi

2013-11-01

Full Text Available Iron chlorosis induced by bicarbonate is very common in calcareous soils, where bicarbonate (HCO3- ions are present at high concentrations. In this study, morpho-physiological and biochemical responses of two Lactuca sativa varieties (Romaine and Vista to bicarbonate induced iron deficiency were investigated. The culture was conducted on nutrient solution containing 5 µM Fe and 10 mM NaHCO3, in a growth chamber with controlled conditions. After 14 days of bicarbonate treatment, the two varieties seedling showed a slight yellowing of young leaves associated with a significant decline of plant biomass, leaf number and area. Furthermore, the concentrations of the nutrient elements (potassium, magnesium, iron and calcium in leaves and roots of two lettuce varieties were modified. In roots of bicarbonate treated plants, the Fe-chelate reductase activity was increased as compared to control in both varieties. PEPC activity was enhanced only in Vista variety. Moreover, Fe deficiency induced a small change in the photosynthetic parameters and chlorophyll fluorescence, especially in Romaine variety. These changes are accompanied by decreases in ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco activity. These findings indicated that Vista variety could survive at low iron supply.

The sporulation of the green alga Ulva prolifera is controlled by changes in photosynthetic electron transport chain.

Science.gov (United States)

Wang, Hui; Lin, Apeng; Gu, Wenhui; Huan, Li; Gao, Shan; Wang, Guangce

2016-04-22

Sporulation and spore release are essential phases of the life cycle in algae and land plants. Ulva prolifera, which is an ideal organism for studying sporulation and spore release, was used as the experimental material in the present study. The determination of photosynthetic parameters, combined with microscopic observation, treatment with photosynthetic inhibitors, limitation of carbon acquisition, and protein mass spectrometry, was employed in this experiment. Cycle electron transport (CEF) was found enhanced at the onset of sporangia formation. The inhibition effect of dibromothymoquinone (DBMIB) towards sporulation was always strong during the sporulation process whereas the inhibition effect of 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU) was continuously declined accompanied with the progress of sporulation. The changes of photosynthesis resulted from the limitation of CO2 acquisition could stimulate sporulation onset. Quantitative protein analysis showed that enzymes involved in carbon fixation, including RUBISCO and pyruvate orthophosphate dikinase, declined during sporogenesis, while proteins involved in sporulation, including tubulin and centrin, increased. These results suggest that enhanced cyclic electron flow (CEF) and oxidation of the plastoquinone pool are essential for sporangia formation onset, and changes in photosynthetic electron transport chain have significant impacts on sporulation of the green algae.

Bioaccumulation of gasoline in brackish green algae and popular clams

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Gihan A. El-Shoubaky

2016-03-01

Full Text Available The green algae (Ulva lactuca and Enteromorpha clathrata and the clams (Tapes decussates and Venerupis aurea grow together in Timsah Lake, Suez Canal, Egypt. Our ultimate goal is to validate the bioaccumulation of gasoline in the marine organisms and their behavior after exposure to the pollutant, experimentally. These species were treated with a serial treatment of gasoline (1000, 4000, 16,000 and 64,000 μl in aquaria with brackish sea-water for 72 h. The tested green algae and clams were taken for an analysis of total hydrocarbon accumulation daily. The statistical analysis showed significant differences between the four species and also between the duration of exposure. The accumulation of gasoline in U. lactuca and E. clathrata reached their maximum after 48 h at 1000 and 4000 μl. The highest absorption was registered after 24 h only at 16,000 and at 64,000 μl. U. lactuca recorded complete mortality in 64,000 μl at 72 h whereas E. clathrata registered death at 48 h and 72 h in the same treatment. V. aurea was more sensitive than T. decussates. The accumulation of gasoline reached its maximum in V. aurea after only 24 h in the first treatment while it retarded to 48 h in T. decussates with a lesser accumulation. However, both clam species accumulated the highest amount of petroleum hydrocarbons during the first hour of exposure at the first treatment. In the third and fourth treatments, clams did not accumulate gasoline but began to dispose it from their tissues till it became less than that in the control. Mortality gradually increased with time in each treatment except the last one (64,000 μl in which 100% death of the specimens was observed. In general, the bioaccumulation of gasoline level was in a descending order as follows: U. lactuca > E. clathrata > V. aurea > T. decussates. Their behavior changed from accumulation to detoxification with time and with the increase in pollutant concentration. Generally, these

Comparative studies of the pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa.

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Naihao Ye

Full Text Available Seaweed has attracted considerable attention as a potential biofuel feedstock. The pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa were studied and compared using heating rates of 10, 30 and 50°C min(-1 under an inert atmosphere. The activation energy, and pre-exponential factors were calculated by the Flynn-Wall-Ozawa (FWO, Kissinger-Akahira-Sunose (KAS and Popescu methods. The kinetic mechanism was deduced by the Popescu method. The results indicate that there are three stages to the pyrolysis; dehydration, primary devolatilization and residual decomposition. There were significant differences in average activation energy, thermal stability, final residuals and reaction rates between the two materials. The primary devolatilization stage of U. pertusa can be described by the Avramic-Erofeev equation (n=3, whereas that of maize straw can be described by the Mampel Power Law (n=2. The average activation energy of maize straw and U. pertusa were 153.0 and 148.7 KJ mol(-1, respectively. The pyrolysis process of U.pertusa would be easier than maize straw. And co-firing of the two biomass may be require less external heat input and improve process stability. There were minor kinetic compensation effects between the pre-exponential factors and the activation energy.

Comparative studies of the pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa.

Science.gov (United States)

Ye, Naihao; Li, Demao; Chen, Limei; Zhang, Xiaowen; Xu, Dong

2010-09-10

Seaweed has attracted considerable attention as a potential biofuel feedstock. The pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa were studied and compared using heating rates of 10, 30 and 50°C min(-1) under an inert atmosphere. The activation energy, and pre-exponential factors were calculated by the Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Popescu methods. The kinetic mechanism was deduced by the Popescu method. The results indicate that there are three stages to the pyrolysis; dehydration, primary devolatilization and residual decomposition. There were significant differences in average activation energy, thermal stability, final residuals and reaction rates between the two materials. The primary devolatilization stage of U. pertusa can be described by the Avramic-Erofeev equation (n=3), whereas that of maize straw can be described by the Mampel Power Law (n=2). The average activation energy of maize straw and U. pertusa were 153.0 and 148.7 KJ mol(-1), respectively. The pyrolysis process of U.pertusa would be easier than maize straw. And co-firing of the two biomass may be require less external heat input and improve process stability. There were minor kinetic compensation effects between the pre-exponential factors and the activation energy.

Isolation, expression and characterization of rbcL gene from Ulva prolifera J. Agardh (Ulvophyceae, Chlorophyta)

Science.gov (United States)

Shao, Zhanru; Li, Wei; Guo, Hui; Duan, Delin

2015-12-01

Ulva prolifera is a typical green alga in subtidal areas and can grow tremendously fast. A highly efficient Rubisco enzyme which is encoded by UpRbcL gene may contribute to the rapid growth. In this study, the full-length UpRbcL open reading frame (ORF) was identified, which encoded a protein of 474 amino acids. Phylogenetic analysis of UpRbcL sequences revealed that Chlorophyta had a closer genetic relationship with higher plants than with Rhodophyta and Phaeophyta. The two distinct residues (aa11 and aa91) were presumed to be unique for Rubisco catalytic activity. The predicted three-dimensional structure showed that one α/β-barrel existed in the C-terminal region, and the sites for Mg2+ coordination and CO2 fixation were also located in this region. Gene expression profile indicated that UpRbcL was expressed at a higher level under light exposure than in darkness. When the culture temperature reached 35°C, the expression level of UpRbcL was 2.5-fold lower than at 15°C, and the carboxylase activity exhibited 13.8-fold decrease. UpRbcL was heterologously expressed in E. coli and was purified by Ni2+ affinity chromatography. The physiological and biochemical characterization of recombinant Rubisco will be explored in the future.

Effects of ozone water on growth of Lactuca sativa var. ramosa Hort and Erwinia carotovora subsp. carotovora

OpenAIRE

Guo Zhenghong; Wang Zuoming; Yin Lijun; Zhao Xuejun; Wang Wenjia; Wang Quanxi

2017-01-01

Research on pathogenic bacteria growth of purple lettuce (Lactuca sativa var. ramosa) and its photosynthetic physiology by being sprayed ozone water on the surface of the purple lettuce with different concentration during the reproductive stage. However,little is known regarding its concentration effect. In this study,we found that ozone water in a low concentration such as 2 mg/L did not inhibit the growth of pathogenic bacteria that originate from purple lettuce and also not affect the phot...

pH gradients in the diffusive boundary layer of subarctic macrophytes

KAUST Repository

Hendriks, Iris E.; Duarte, Carlos M.; Marbà , Nú ria; Krause-Jensen, Dorte

2017-01-01

Highly productive macrophytes produce diurnal and seasonal cycles in CO concentrations modulated by metabolic activity, which cause discrepancies between pH in the bulk water and near seaweed blades, especially when entering the diffusion boundary layer (DBL). Calcifying epiphytic organisms living in this environment are therefore exposed to a different pH environment than that of the water column. To evaluate the actual pH environment on blade surfaces, we measured the thickness of the DBL and pH gradients within it for six subarctic macrophytes: Fucus vesiculosus, Ascophyllum nodosum, Ulva lactuca, Zostera marina, Saccharina longicruris, and Agarum clathratum. We measured pH under laboratory conditions at ambient temperatures (2–3 °C) and slow, stable flow over the blade surface at five light intensities (dark, 30, 50, 100 and 200 µmol photons m s). Boundary layer thickness ranged between 511 and 1632 µm, while the maximum difference in pH (∆pH) between the blade surface and the water column ranged between 0.4 ± 0.14 (average ± SE; Zostera) and 1.2 ± 0.13 (average ± SE; Ulva) pH units. These differences in pH are larger than predictions for pH changes in the bulk water by the end of the century. A simple quadratic model best described the relationship between light intensity and maximum ∆pH, pointing at relatively low optimum PAR of between 28 and 139 µmol photons m s to reach maximum ∆pH. Elevated pH at the blade surface may provide chemical “refugia” for calcifying epiphytic organisms, especially during summer at higher latitudes where photoperiods are long.

pH gradients in the diffusive boundary layer of subarctic macrophytes

KAUST Repository

Hendriks, Iris E.

2017-06-20

Highly productive macrophytes produce diurnal and seasonal cycles in CO concentrations modulated by metabolic activity, which cause discrepancies between pH in the bulk water and near seaweed blades, especially when entering the diffusion boundary layer (DBL). Calcifying epiphytic organisms living in this environment are therefore exposed to a different pH environment than that of the water column. To evaluate the actual pH environment on blade surfaces, we measured the thickness of the DBL and pH gradients within it for six subarctic macrophytes: Fucus vesiculosus, Ascophyllum nodosum, Ulva lactuca, Zostera marina, Saccharina longicruris, and Agarum clathratum. We measured pH under laboratory conditions at ambient temperatures (2–3 °C) and slow, stable flow over the blade surface at five light intensities (dark, 30, 50, 100 and 200 µmol photons m s). Boundary layer thickness ranged between 511 and 1632 µm, while the maximum difference in pH (∆pH) between the blade surface and the water column ranged between 0.4 ± 0.14 (average ± SE; Zostera) and 1.2 ± 0.13 (average ± SE; Ulva) pH units. These differences in pH are larger than predictions for pH changes in the bulk water by the end of the century. A simple quadratic model best described the relationship between light intensity and maximum ∆pH, pointing at relatively low optimum PAR of between 28 and 139 µmol photons m s to reach maximum ∆pH. Elevated pH at the blade surface may provide chemical “refugia” for calcifying epiphytic organisms, especially during summer at higher latitudes where photoperiods are long.

Agronomical response of lettuce (Lactuca sativa L., variety “Black Seed Simpson”, to Enerplant biostimulant aplication

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Michel Baldoquin Hernandez

2015-03-01

Full Text Available The research was done at the school vegetable garden of Los Indios in the municipality of Rio Cauto, Granma, from March through April, 2014. The objective was to evaluate the agronomical response of the cultivation of the lettuce (Lactuca sativa. L variety “Black Seeded Simpson to the foliar application of three doses of Enerplant. The biostimulant was applied in the morning 7 days after transplantation. The doses used were 0.5 mL.ha-1, 1 mL.ha-1 and 1.5 mL.ha-1. The yield components were evaluated. The obtained data were statistically processed using the software package STASTISTICA 6.0 for Windows. Results showed that the three doses had a positive effect on the cultivation yield. Best results were obtained with the application of the 1.5 mL.ha-1 dose. The majority of the evaluated indicators significantly increased.

Determination of Profenofos Pesticidal Residue in Lettuce (Lactuca sativa L. by Gas Chromatographic Method

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Yohannes Alen

2015-05-01

Full Text Available The determination of profenofos pesticidal residue in the lettuce (Lactuca sativa L. by using gas chromatography using flame photometric detector (FPD had been investigated. The lettuce was collected from Padang Luar area, Agam distric, West Sumatera. Sample for determination of profenofos residue divided into three groups: unwashed (A, washed with water (B, and washed with detergent (C. Maceration with sonication was used for the extraction using ethylacetateas a solvent. The results showed that profenofos pesticide residue in sample A, B and C were 0.204, 0.080 and 0.061 ppm, respectively. These profenofos pesticidal residue are over than the Maximum Residue Limits (MRL that established by The Japan Food Chemical Research Foundation (0.05 ppm even though World Health Organization (WHO has not established Maximum Residue Limits (MRL profenofos on lettuce. Based on the statistical analysis one-way method (Anova using SPSS 20.0 showed that there was a significant concentrations difference between lettuce A from lettuce B and lettuce C with p < 0.05.

Chryseobacterium formosense sp. nov., isolated from the rhizosphere of Lactuca sativa L. (garden lettuce).

Science.gov (United States)

Young, Chiu-Chung; Kämpfer, Peter; Shen, Fo-Ting; Lai, Wei-An; Arun, A B

2005-01-01

A yellow-pigmented bacterial strain (CC-H3-2T), isolated from the rhizosphere of Lactuca sativa L. (garden lettuce) in Taiwan, was investigated using a polyphasic taxonomic approach. The cells were Gram-negative, rod-shaped and non-spore-forming. Phylogenetic analyses using the 16S rRNA gene sequence of the isolate indicated that the organism belongs to the genus Chryseobacterium, with the highest sequence similarity to the type strains of Chryseobacterium indoltheticum (97.7 %), Chryseobacterium scophthalmum (97.5 %), Chryseobacterium joostei (97.2 %) and Chryseobacterium defluvii (97.2 %). The major whole-cell fatty acids were iso-C(15 : 0) (52.2 %) and iso-C(17 : 0) 3-OH. DNA-DNA hybridization experiments revealed levels of only 27.4 % to C. scophthalmum, 27.1 % to C. indoltheticum, 14.1 % to C. joostei and 7.8 % to C. defluvii. DNA-DNA relatedness and biochemical and chemotaxonomic properties demonstrate that strain CC-H3-2T represents a novel species, for which the name Chryseobacterium formosense sp. nov. is proposed. The type strain is CC-H3-2T (=CCUG 49271T=CIP 108367T).

Carotenoids of lettuce (Lactuca sativa L.) grown on soil enriched with spent coffee grounds.

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Cruz, Rebeca; Baptista, Paula; Cunha, Sara; Pereira, José Alberto; Casal, Susana

2012-02-07

The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata) was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v). All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%). This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

Carotenoids of Lettuce (Lactuca sativa L. Grown on Soil Enriched with Spent Coffee Grounds

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Susana Casal

2012-02-01

Full Text Available The impact of spent coffee grounds on carotenoid and chlorophyll content in lettuce (Lactuca sativa L. var. capitata was evaluated. A greenhouse pot experiment was conducted with spent coffee amounts ranging from 0% to 20% (v/v. All evaluated pigments increased proportionally to spent coffee amounts. Lutein and β-carotene levels increased up to 90% and 72%, respectively, while chlorophylls increased up to 61%. Biomass was also improved in the presence of 2.5% to 10% spent coffee, decreasing for higher amounts. Nevertheless, all plants were characterized by lower organic nitrogen content than the control ones, inversely to the spent coffee amounts, pointing to possible induced stress. Collected data suggests that plants nutritional features, with regards to these bioactive compounds, can be improved by the presence of low amounts of spent coffee grounds (up to 10%. This observation is particularly important because soil amendment with spent coffee grounds is becoming increasingly common within domestic agriculture. Still, further studies on the detailed influence of spent coffee bioactive compounds are mandatory, particularly regarding caffeine.

Effects of dietary supplementation of Ulva pertusa and non-starch polysaccharide enzymes on gut microbiota of Siganus canaliculatus

Science.gov (United States)

Zhang, Xinxu; Wu, Huijuan; Li, Zhongzhen; Li, Yuanyou; Wang, Shuqi; Zhu, Dashi; Wen, Xiaobo; Li, Shengkang

2018-03-01

Fishes represent the highest diversity of vertebrates; however, our understanding of the compositions and functions of their gut microbiota is limited. In this study, we provided the first insight into the gut microbiota of the herbivorous fish Siganus canaliculatus by using three molecular ecology techniques based on the 16S rRNA genes (denaturing gradient gel electrophoresis, clone library construction, and highthroughput Illumina sequencing), and the Illumina sequencing technique is suggested here due to its higher overall coverage of the total 16S rRNA genes. A core gut microbiota of 29 bacterial groups, covering >99.9% of the total bacterial community, was found to be dominated by Proteobacteria and Firmicutes in fish fed three different diets with/without the supplementation of Ulva pertusa and non-starch polysaccharide (NSP) enzymes (cellulase, xylanase, and β-glucanase). Diverse potential NSP-degrading bacteria and probiotics (e.g., Ruminococcus, Clostridium and Lachnospiraceae) were detected in the intestine of the fish fed U. pertusa, suggesting that these microorganisms likely participated in the degradation of NSPs derived from U. pertusa. This study supports our previous conclusion that U. pertusa-based diets are suitable for the production of S. canaliculatus with lower costs without compromising quality.

Production of Biofuels from Marine Macroalgae Melanothamnus afaqhusainii and Ulva fasciata

International Nuclear Information System (INIS)

Khan, A. M.; Hussain, M. K.

2015-01-01

This research article is based on the production of biofuels from the marine macro red alga Melanothamnus afaqhusainii and marine macro green alga Ulva fasciata from the Karachi coast. M. afaqhusainii was investigated for biodiesel as well as for bioethanol whereas U. fasciata was investigated only for bioethanol. Two types of biodiesels namely fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE) were prepared by the transesterification of algal oil. The carbohydrates from both algae were extracted by distilled water and subjected to different biochemical tests. It was hydrolyzed by various methods including acidic and basic as well as by using ammonia, hydrogen peroxide and mixture of organic solvents in the presence of AlCl/sub 3/. The comparative study of these methods revealed their efficiency order as NaOH (10 percentage)/heating (method-2) > NaOH (10 percentage)/H/sub 2/O/sub 2/ in microwave oven (method-5) > ammonia (50 percentage)/reflux (method-6). After hydrolysis, the presence of carbohydrates in the hydrolyzed samples was investigated by different biochemical tests including Molisch Test, Iodine Test, Benedict Test, Tollen Test, Barfoed's Test, Fehling solution Test, Osazone Test, Seliwanoff's Test and Bial's Test. In addition, the presence of glucose was confirmed by glucometer and Combur Test. The detailed investigation of carbohydrates was carried out that resulted in the identification of reducing sugars, polysaccharides, disaccharides and monosaccharides including glucose. The hydrolyzed samples were fermented by Saccharomyces cerevisiae under ground and paratial anaerobic conditions. The bioethanol so formed by fermentation was directly converted to UV active derivatives namely ethyl benzoate and benzyl acetate. They were confirmed by TLC examination in comparison with standard ethyl benzoate and benzyl acetate. UV spectrophotometer was used for the determination of total sugar and bioethanol on the basis of absorbance

El modelo V.S.P. en lechuga Batavia Lactuca sativa var. Capitata L. y respuesta de dos variedades a las aplicaciones de compuestos orgánicos

OpenAIRE

Bruzón C. Serapio F.; Vélez M. José F.; Garzón José L.

1996-01-01

An investigation was realized in the region of Pavitas, municipality of La Cumbre, Santa Fe farm, 1480 meters above sea level in a soil of Pavas Association (Aeric Tropaquept) to prove the plastic cup-sustrate-plant model in the production of Batavia lecttuce Lactuca sativa var. capitata, and the effects of the organic matter filter cake press, cattle manure, poultry manure and earthworm soil, incorporated in the soil. Twenty two (22) treatments and fours repetitions were applied wit...

Factors influencing the sporulation and cyst formation of Aphanomyces invadans, etiological agent of ulcerative mycosis in Atlantic menhaden, Brevoortia tyrannus

Science.gov (United States)

Kiryu, Y.; Blazer, V.S.; Vogelbein, W.K.; Kator, H.; Shields, J.D.

2005-01-01

Oomycete infections caused by Aphanomyces invadans occur in freshwater and estuarine fishes around the world. Along the east coast of the USA, skin ulcers caused by A. invadans are prevalent in Atlantic menhaden, Brevoortia tyrannus. From laboratory observations low salinities appear crucial to transmission of the pathogen. To better understand aspects of transmission, we characterized sporulation and cyst formation of secondary zoospores of two isolates of A. invadans at different salinities and temperatures. Sporulation occurred only at low salinities. At room temperature (ca. 20-22 C), using "pond water" augmented with artificial sea salts, the endemic strain WIC and the Thailand strain PA7 of A. invadans produced free-swimming secondary zoospores at salinities of 0, 1 and 2 psu (practical salinity unit = ???), but not at 4 psu or higher. Secondary zoospores of another species, ATCC-62427 (Aphanomyces sp.), were observed at 1, 2, 4 and 8 psu but not at 0 and 12 psu. Secondary zoospores of all three isolates, especially WIC, were abundant and motile 1-2 d post-sporulation. Sporulation was temperature dependent and occurred over a relatively narrow range. No sporulation occurred at 4, 30 or 35 C for either WIC or PA7. For both strains zoospore production within 1-3 d after the initiation of sporulation was more prolific at 25 C than at 20 and 15 C. At 15 C production of zoospores was sustained over 11 d for WIC and 5 d for PA7. At room temperature single WIC secondary zoospores remained motile 12-18 h. Salinities exceeding 4 psu or vigorous shaking caused immediate cyst formation of WIC secondary zoospores. Exposure to menhaden tissue, but not tissues of other fishes to secondary zoospores (WIC), caused rapid (2 h) cyst formation. Cysts were capable of excysting when transferred to 1 psu water within 2-3 h of cyst formation. Cysts that had remained encysted in 6.5 psu for 24 h did not excyst when transferred to 1 psu water. Salinity and temperature requirements

Screening and isolation of the algicidal compounds from marine green alga Ulva intestinalis

Science.gov (United States)

Sun, Xue; Jin, Haoliang; Zhang, Lin; Hu, Wei; Li, Yahe; Xu, Nianjun

2016-07-01

Twenty species of seaweed were collected from the coast of Zhejiang, China, extracted with ethanol, and screened for algicidal activity against red tide microalgae Heterosigma akashiwo and Prorocentrum micans. Inhibitory effects of fresh and dried tißsues of green alga Ulva intestinalis were assessed and the main algicidal compounds were isolated, purified, and identified. Five seaweed species, U. intestinalis, U. fasciata, Grateloupia romosissima, Chondria crassicaulis, and Gracilariopsis lemaneiformis, were investigated for their algicidal activities. Fresh tissues of 8.0 and 16.0 mg/mL of U. intestinalis dissolved in media significantly inhibited growth of H. akashiwo and P. micans, respectively. Dried tissue and ethyl acetate (EtOAc) extracts of U. intestinalis at greater than 1.2 and 0.04 mg/mL, respectively, were fatal to H. akashiwo, while its water and EtOAc extracts in excess of 0.96 and 0.32 mg/mL, respectively, were lethal to P. micans. Three algicidal compounds in the EtOAc extracts were identified as 15-ethoxy-(6z,9z,12z)-hexadecatrienoic acid (I), (6E,9E,12E)-(2-acetoxy- β-D-glucose)-octadecatrienoic acid ester (II) and hexadecanoic acid (III). Of these, compound II displayed the most potent algicidal activity with IC50 values of 4.9 and 14.1 µg/mL for H. akashiwo and P. micans, respectively. Compound I showed moderate algicidal activity with IC50 values of 13.4 and 24.7 µg/mL for H. akashiwo and P. micans, respectively. These findings suggested that certain macroalgae or products therefrom could be used as effective biological control agents against red tide algae.

Evaluation of response of lettuce (Lactuca sativa L. to temperature and light stress

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Nidal Tabit Shaban

2016-06-01

Full Text Available The aim of the study was to assess the effect of irrigation water temperature and shading on the rate of photosynthesis and transpiration in four varieties of lettuce (Lactuca sativa L. – green foliage (‘Salakis’ and ‘Estony’ and red foliage (‘Lollo Rossa’ and ‘Nika’. During the production of seedlings in the greenhouse, two irrigation water temperature regimes (12 and 20°C were applied. After transplanting in the field plants were grown under three lighting systems (100, 70, and 50% of lighting in the open. The rates of photosynthesis and transpiration were measured at the end of the greenhouse period and 14 days after shading in the field using a Li 6400 infrared gas analyzer. In most varieties, cooling of the irrigation water was not found to have an effect on the rate of photosynthesis. Plants of all the varieties responded to the decrease in irrigation water temperature and to strong shading by reducing transpiration and increasing the water use efficiency. The ‘Salakis’ and ‘Estony’ plants have shown the best adaptability to the changing conditions and therefore they could be used successfully in the practice of extending vegetative growth.

Performance and feeding behaviour of two biotypes of the black currant-lettuce aphid, Nasonovia ribisnigri, on resistant and susceptible Lactuca sativa near-isogenic lines.

Science.gov (United States)

ten Broeke, Cindy J M; Dicke, Marcel; van Loon, Joop J A

2013-10-01

The black currant-lettuce aphid, Nasonovia ribisnigri, is an important pest of cultivated lettuce, Lactuca sativa. Since 1982, the control of this aphid on lettuce is largely based on host plant resistance, conferred by the Nr gene, introgressed from Lactuca virosa. The resistance mechanism remains to be identified. N. ribisnigri populations virulent on the Nr-based resistance in lettuce have emerged in several locations in Europe since 2007. The objective of this study was to investigate the resistance mechanism mediated by the Nr gene in lettuce by detailed studies of aphid feeding behaviour and performance. Both avirulent (Nr:0) and virulent (Nr:1)biotypes of N. ribisnigri were studied on five resistant and two susceptible near isogenic lines (NILs). In addition, survival and colony development were quantified.Nr:0 aphids showed a strong decrease in sieve element ingestion and took longer to accept a sieve element on resistant NILs compared with susceptible NILs, and no aphids survived on the resistant NIL. Nr:1 aphids fed and performed equally well on the resistant and susceptible NILs. The resistance mechanism against Nr:0 aphids encoded by the Nr gene seems to be located in the phloem, although we also observed differences in feeding behaviour during the pathway phase to the phloem. Nr:1 aphids were highly virulent to the resistance conferred by the Nr gene. The consequences of the appearance of Nr:1 aphids for control of N. ribisnigri are discussed.

Evolución temporal de la contaminación por plomo y cadmio en la zona intermareal de la ría de Vigo

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M. Pérez López

2004-12-01

Full Text Available En el presente trabajo se han recogido muestras de lapa (Patella vulgata L. y alga verde (Ulva lactuca en un mismo punto de muestreo de la ría de Vigo, con una periodicidad mensual, a lo largo de un año, analizándose por medio de voltamperometría de redisolución anódica la concentración en dos metales pesados con claras repercusiones toxicológicas, cadmio y plomo, en estas muestras, así como en el agua marina. Los resultados obtenidos mostraron la mayor concentración de ambos metales en los tejidos blandos de las lapas frente a las valvas de estos moluscos, con valores máximos en el caso del plomo próximos a 3 ppm (valva de lapa, mientras que para el cadmio se situó en torno a 1,1 ppm (alga verde. El estudio estadístico permitió poner en evidencia una clara correlación estadística entre los valores de cadmio y plomo cuantificados en las muestras de algas.

On the recurrent Ulva prolifera blooms in the Yellow Sea and East China Sea

Science.gov (United States)

Hu, Chuanmin; Li, Daqiu; Chen, Changsheng; Ge, Jianzhong; Muller-Karger, Frank E.; Liu, Junpeng; Yu, Feng; He, Ming-Xia

2010-05-01

A massive bloom of the green macroalgae Ulva prolifera (previously known as Enteromorpha prolifera) occurred in June 2008 in the Yellow Sea (YS), resulting in perhaps the largest "green tide" event in history. Using a novel index (Floating Algae Index) and multiresolution remote sensing data from MODIS and Landsat, we show that U. prolifera patches appeared nearly every year between April and July 2000-2009 in the YS and/or East China Sea (ECS), which all originated from the nearshore Subei Bank. A finite volume numerical circulation model, driven by realistic forcing and boundary conditions, confirmed this finding. Analysis of meteorological/environmental data and information related to local aquaculture activities strongly supports the hypothesis that the recurrent U. prolifera in the YS and ECS resulted from aquaculture of the seaweed Porphyra yezoensis (or nori) conducted along the 200 km shoreline of the Subei Bank north of the Changjiang (Yangtze) River mouth. Given the continuous growth in aquaculture efforts in the region, similar macroalgae bloom events, such as the summer 2008 event, are likely to occur in the future, particularly between May and July. This was confirmed by the 2009 bloom event in the same regions and the same period. The profit of the local P. yezoensis aquaculture industry (˜16,000 Ha in 2007) is estimated as U.S. 53 million, yet the cost to manage the impact of the summer 2008 U. prolifera bloom exceeded U.S. 100 million. Therefore, better strategies are required to balance the economic benefit of seaweed aquaculture and the costs of environmental impacts.

Desiccation induces accumulations of antheraxanthin and zeaxanthin in intertidal macro-alga Ulva pertusa (Chlorophyta.

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Xiujun Xie

Full Text Available For plants and algae, exposure to high light levels is deleterious to their photosynthetic machineries. It also can accelerate water evaporation and thus potentially lead to drought stress. Most photosynthetic organisms protect themselves against high light caused photodamages by xanthophyll cycle-dependent thermal energy dissipation. It is generally accepted that high light activates xanthophyll cycle. However, the relationship between xanthophyll cycle and drought stress remains ambiguous. Herein, Ulva pertusa (Chlorophyta, a representative perennial intertidal macro-algae species with high drought-tolerant capabilities and simple structures, was used to investigate the operation of xanthophyll cycle during desiccation in air. The results indicate that desiccation under dim light induced accumulation of antheraxanthin (Ax and zeaxanthin (Zx at the expense of violaxanthin (Vx. This accumulation could be arrested by dithiothreitol completely and by uncoupler (carbonyl cyanide p-trifluoromethoxyphenylhydrazone partially, implying the participation of Vx de-epoxidase in conversion of Vx to Ax and Zx. Treatment with inhibitors of electron transport along thylakoid membrane, e.g. DCMU, PG and DBMIB, did not significantly arrest desiccation-induced accumulation of Ax and Zx. We propose that for U. pertusa, besides excess light, desiccation itself could also induce accumulation of Ax and Zx. This accumulation could proceed without electron transport along thylakoid membrane, and is possibly resulting from the reduction of thylakoid lumen volume during desiccation. Considering the pleiotropic effects of Ax and Zx, accumulated Ax and Zx may function in protecting thylakoid membrane and enhancing thermal quenching during emersion in air.

Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China

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Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B.; Legendre, Louis

2016-05-01

The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3-), ammonium (NH4+), urea and glycine] and phosphorus [i.e. phosphate (PO43-), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3- and NH4+) and phosphorus (PO43-). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea.

REMOVAL OF AMMONIA TOXCITY IN MARINE SEDIMENT TIES: A COMPARISON OF ULVA LACTUCA, ZEOLITE AND AREATION METHODS

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Ammonia is suspected of causing some of the toxicity observed in marine sediment toxicity tests because it is sometimes found at elevated concentrations in marine interstitial waters. In marine waters, ammonia exists as un-ionized ammonia (NH3) and ammonium (NH4+) which combine ...

Physiological and physico-chemical characterization of dietary fibre from the green seaweed Ulva fasciata Delile.

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Carvalho, A F U; Portela, M C C; Sousa, M B; Martins, F S; Rocha, F C; Farias, D F; Feitosa, J P A

2009-08-01

This work aims to assess the potential of the green seaweed Ulva fasciata Delile as an alternative source of dietary fibre (DF). Total DF content was determined, some of its physico-chemical properties described and the physiological effects of U. fasciata meal on rats fed a hypercholesterolemic diet were investigated. U. fasciata may be considered a potential alternative source of DF with a total content of about 400 g.kg-1 (dry basis) and interesting physico-chemical properties: water retention capacity of 8.74 g/water.g-1 dry sample (seaweed meal) and 0.90 (seaweed carbohydrate extract), lipid adsorption capacity of 4.52 g/oil.g-1 dry sample (seaweed meal) and 5.70 (seaweed carbohydrate extract), intrinsic viscosity of 2.4 dl.g-1 (seaweed carbohydrate extract) and cation exchange capacity of 3.51 Eq.kg-1 (seaweed carbohydrate extract). The diet containing seaweed meal was able to keep rats' total cholesterol (TC) down without causing any undesirable increase in LDL-C fraction. No evidence of toxic and/or antinutritional components in the seaweed meal was detected. Rats showed a fecal volume much greater (13 g) than that fed on cellulose diet (7 g) (p seaweed the potential to be used in food technology for the acquisition of low-calorie food and might be important in body weight control, reduction of blood TC and LDL-C as well as in prevention of gastrointestinal diseases.

Physiological and physico-chemical characterization of dietary fibre from the green seaweed Ulva fasciata Delile

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AFU. Carvalho

Full Text Available This work aims to assess the potential of the green seaweed Ulva fasciata Delile as an alternative source of dietary fibre (DF. Total DF content was determined, some of its physico-chemical properties described and the physiological effects of U. fasciata meal on rats fed a hypercholesterolemic diet were investigated. U. fasciata may be considered a potential alternative source of DF with a total content of about 400 g.kg-1 (dry basis and interesting physico-chemical properties: water retention capacity of 8.74 g/water.g-1 dry sample (seaweed meal and 0.90 (seaweed carbohydrate extract, lipid adsorption capacity of 4.52 g/oil.g-1 dry sample (seaweed meal and 5.70 (seaweed carbohydrate extract, intrinsic viscosity of 2.4 dl.g-1 (seaweed carbohydrate extract and cation exchange capacity of 3.51 Eq.kg-1 (seaweed carbohydrate extract. The diet containing seaweed meal was able to keep rats' total cholesterol (TC down without causing any undesirable increase in LDL-C fraction. No evidence of toxic and/or antinutritional components in the seaweed meal was detected. Rats showed a fecal volume much greater (13 g than that fed on cellulose diet ( 7 g (p < 0.05. These properties confer on the seaweed the potential to be used in food technology for the acquisition of low-calorie food and might be important in body weight control, reduction of blood TC and LDL-C as well as in prevention of gastrointestinal diseases.

Análisis técnico de producción de tilapia Oreochromis niloticus y lechuga acrópolis Lactuca sativa en acuaponia

OpenAIRE

Rubio Cabrera, Sheila Guadalupe

2014-01-01

Se evaluó la producción de tilapia Oreochromis niloticus y lechuga romana acropolis Lactuca sativa en sistemas acuapónicos utilizando dos sistemas: recirculación de agua sin recambio (utilizando biofiltración) y sistema sin recirculación con recambio parcial de agua. El cultivo se realizó en 4 etapas. En la primera se colocaron 800 alevines de O. niloticus de 0.2 g de peso inicial en tinas plásticas de 800 L (1600 organismos/m3de agua) durante 39 días. La segunda etapa con u...

Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.)

Science.gov (United States)

Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

2018-01-01

Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce. PMID:29403510

Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.).

Science.gov (United States)

Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan

2017-01-01

Lettuce ( Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.

Uptake of perfluorinated alkyl acids by hydroponically grown lettuce (Lactuca sativa).

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Felizeter, Sebastian; McLachlan, Michael S; de Voogt, Pim

2012-11-06

An uptake study was carried out to assess the potential human exposure to perfluorinated alkyl acids (PFAAs) through the ingestion of vegetables. Lettuce (Lactuca sativa) was grown in PFAA-spiked nutrient solutions at four different concentrations, ranging from 10 ng/L to 10 μg/L. Eleven perfluorinated carboxylic acids (PFCAs) and three perfluorinated sulfonic acids (PFSAs) were analyzed by HPLC-MS/MS. At the end of the experiment, the major part of the total mass of each of the PFAAs (except the short-chain, C4-C7, PFCAs) taken up by plants appeared to be retained in the nonedible part, viz. the roots. Root concentration factors (RCF), foliage/root concentration factors (FRCF), and transpiration stream concentration factors (TSCF) were calculated. For the long chained PFAAs, RCF values were highest, whereas FRCF were lowest. This indicates that uptake by roots is likely governed by sorption of PFAAs to lipid-rich root solids. Translocation from roots to shoots is restricted and highly depending on the hydrophobicity of the compounds. Although the TSCF show that longer-chain PFCAs (e.g., perfluorododecanoic acid) get better transferred from the nutrient solution to the foliage than shorter-chain PFCAs (e.g., perfluoroheptanoic acid), the major fraction of longer-chain PFCAs is found in roots due to additional adsorption from the spiked solution. Due to the strong electron-withdrawing effect of the fluorine atoms the role of the negative charge of the dissociated PFAAs is likely insignificant.

Parasitos em alfaces (Lactuca sativa de mercados e feiras livres de Lages - Santa Catarina = Lettuces (Lactuca sativa parasites in markets and free fairs from Lages - Santa Catarina

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Quadros, Rosiléia Marinho de

2008-01-01

Full Text Available Objetivo: avaliar a contaminação por parasitos de interesse em Saúde Pública em alfaces (Lactuca sativa comercializadas no município de Lages, Santa Catarina. Materiais e Métodos: Foi utilizado um processo de amostragem intencional, selecionando-se oito supermercados e duas feiras, de acordo com a abrangência e volume de vendas desses estabelecimentos para a cidade. Foram processadas 122 amostras de alfaces, pelas técnicas de sedimentação espontânea (Lutz, centrífugo-flutuação em sulfato de zinco (Faust, centrífugo-flutuação em solução de sacarose (Sheather e coloração de Ziehl Neelsen modificada. Resultados: O índice de parasitismo foi de 88,5% (108/122 com 77% (94/122 e 11,5% (14/122 para as amostras de supermercados e de feiras livres, respectivamente. A técnica de Lutz detectou 46,7% (57/122 de alfaces parasitadas; Sheather e Faust evidenciaram 31,1% (38/122 e 10,6% (13/122 de alfaces com ovos e/ou oocistos de parasitos, respectivamente. Predominaram os gêneros Eimeria, Giardia e Entamoeba. Conclusões: As amostras analisadas apresentaram baixos padrões higiênicos, necessitando de vigilância sanitária mais atuante na fiscalização de todas as etapas do processo produtivo de hortaliças

Allelopathic effect of medicinal plant Cannabis sativa L. on Lactuca sativa L. seed germination

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Homa MAHMOODZADEH

2015-11-01

Full Text Available In order to examine allelopathic effect of Cannabis sativa L. on germination capability and seedling growth of Lactuca sativa L., a study was performed in laboratory conditions. Treatments were set up in randomised block design in four replications for each of four concentration ranges of 25, 50, 75 and 100 % of aqueous extract made of shoot parts and 4 identical extract concentrations made of root of cannabis. Control variant was lettuce seed treated by distilled water. During the studies shoot and seminal root length of lettuce seedlings were measured after treatments with different concentrations of extracts made of root and shoot parts of cannabis, and the obtained values were compared with the control. The obtained results suggest that the extract from the shoot parts of cannabis in high concentrations of 75 and 100 % had inhibiting effect to the germination indices while the extract from the root had no statistically significant effect on germination of lettuce seeds. Extract made of root part of cannabis showed also stimulatory effect to shoot and seminal root length of lettuce seedlings in extract concentrations of 50, 75 and 100 %.

Occurrence of the PsbS and LhcSR products in the green alga Ulva linza and their correlation with excitation pressure.

Science.gov (United States)

Zhang, Xiaowen; Ye, Naihao; Mou, Shanli; Xu, Dong; Fan, Xiao

2013-09-01

To avoid photoinhibition, plants have developed diverse photoprotection mechanisms. One of the short-term high light protection mechanisms in plants is non-photochemical quenching (NPQ), which dissipates the absorbed light energy as thermal energy. In the green alga, Ulva linza, the kinetics of NPQ starts with an initial, quick rise followed by a decline, and then a second and higher rise at longer time periods. During the whole phase, NPQ is triggered and controlled by ΔpH, then strengthened and modulated by zeaxanthin. Light-harvesting complex (LHC) family members are known to play crucial roles in this mechanism. The PSBS protein, a member of the LHC family that was thought to be present exclusively in higher plants, has been identified for the first time in U. linza. The expression of both PSBS and LHCSR was up-regulated during high light conditions, and LHCSR increased more than PSBS. Both LHCSR and PSBS-dependent NPQ may be important strategies for adapting to the environment, and they have undoubtedly played a role in their evolution. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

A rapid and efficient in vitro regeneration system for lettuce (Lactuca sativa L.).

Science.gov (United States)

Armas, Isabel; Pogrebnyak, Natalia; Raskin, Ilya

2017-01-01

Successful biotechnological improvement of crop plants requires a reliable and efficient in vitro regeneration system. Lettuce ( Lactuca sativa L.), one the most important vegetable crops worldwide, is strongly genotype-dependent in terms of regeneration capacity, limiting the potential for biotechnological improvement of cultivars which show recalcitrance under currently available protocols. The effect of different nutrient sources, plant hormone combinations and activated charcoal supplementation on shoot induction efficiency was evaluated on the cultivar 'RSL NFR', which had previously shown poor regeneration efficiency. Multiple shoot organogenesis from cotyledon explants was recorded at the highest frequency and speed on Murashige and Skoog regeneration medium supplemented with 200 mg/l of activated charcoal, 3% sucrose, 10 mg/l benzylaminopurine and 0.5 mg/l naphthaleneacetic acid, which induced shoots through direct regeneration in 90.8 ± 7.9% of explants. High shoot induction efficiency was also observed, albeit not quantified, when using this medium on some other cultivars. This activated charcoal-containing regeneration medium might offer a rapid and efficient option for direct shoot induction in some lettuce genotypes that do not respond well to common lettuce regeneration protocols. This is also the first report of the effect of activated charcoal in lettuce tissue culture.

STUDI KOMUNITAS RUMPUT LAUT DI PANTAI SANUR DAN PANTAI SAWANGAN NUSA DUA BALI

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GALIH INDRAWATI

2012-11-01

Full Text Available Aims of this research are to analyze structure community population, relative population, variety domination, heterogeneous, and equality of seaweed species in Sanur and Sawangan Beach Nusa Dua.The result of the study shows that in Sanur and Sawangan Beach observed 13 related seaweed species were observed, which are: Ulva reticulata, Chaetomorpha crassa, Bornetella nitida, Halimeda macroloba, Padina australis, Sargassum binderi, Hypnea asperi, Dictyopteris sp, Gracilaria coronapifolia, Gracilaria gracilis, Acanthopora spicifera, Euchema edule, Euchema denticulatum Meanwhile, , Caulerpa racemosa, Boergesiana forbessii, Sargassum crassifolium, Gelidium sp, Turbinaria ornata, Gracilaria foliifera only observed in Sanur Beach and species of Actinotrichia fragilis, Ulva lactuca, Euchema serra, Turbinaria conoides observed in Sawangan Beach, Nusa Dua.Heterogeneous value index (H in Sanur Beach is 0.75 – 1.87 categorized as medium category, except in station five characterized as low category. Domination index (C is 0.10 – 0.28, where there is no dominated species. Equality index value (E is 0.32 – 0.85 in unstable condition, except in station one is stable. In Sawangan Beach, heterogeneous indexes is 1.04 – 1.54, that spread in all stations by medium category. Domination index is 0.14 – 0.30, indicated that there is no dominant species. Equality index is 0.47 – 0.74, by stabile condition in station one, while others station is unstable. Highest relatif population in Sanur Beach is 37.63% in station three (Gracilaria foliifera. In Sawangan Nusa Dua Beach is Hypnea asperi (48.65%.Substrate analysis show that Sanur and Sawangan Beach has mud sand types. Water temperature in both research locations approximately is 28.90 C – 30.40 C, pH 7.00 – 7.80 and dissolved oxygen around 6.8mg/1-7.4mg/l.

Effects of ozone water on growth of Lactuca sativa var. ramosa Hort and Erwinia carotovora subsp. carotovora

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Guo Zhenghong

2017-10-01

Full Text Available Research on pathogenic bacteria growth of purple lettuce (Lactuca sativa var. ramosa and its photosynthetic physiology by being sprayed ozone water on the surface of the purple lettuce with different concentration during the reproductive stage. However,little is known regarding its concentration effect. In this study,we found that ozone water in a low concentration such as 2 mg/L did not inhibit the growth of pathogenic bacteria that originate from purple lettuce and also not affect the photosynthetic physiology of purple lettuce;in a high concentration,for example,14 mg/L,can completely suppressed the growth of pathogenic bacteria but,significantly influenced the activity of photosynthetic physiology;and in a moderate amount (6 mg/L not only completely impeded the growth of pathogenic bacteria,but also slightly increased the activity of photosynthetic physiology. Based on the above results,we propose that spraying the purple lettuce with a moderate concentration of ozone water is an efficient strategy for green disinfection.

Effect of partially purified components of zoospores and mycelia of phytophthora infestans on uptake of 3H-leucine by potato tuber disks

International Nuclear Information System (INIS)

Nishimura, Norio; Tomiyama, Kohei; Doke, Noriyuki

1980-01-01

The zoosporial component of Phytophthora infestans, which was previously reported to cause reduction of 3 H-leucine uptake by potato tuber disks, was partially purified. Precipitate (A-fraction) was obtained by homogenizing zoospores with acetate buffer at pH 4.5 and centrifuging at 20,000 x g, and the A-fraction was suspended in borate buffer at pH 8.8, boiled for 1 hr and then centrifuged at 20,000 x g, giving the precipitate (B-fraction) and supernatant (C-fraction). Ten ml of 10 mM tris-HCl buffer containing 1 mM CaCl 2 at pH 7.4 was used to suspend A and B-fraction. The buffer was used as a control. A, B and C fractions obtained from 5 - 6 x 10 6 zoosprores reducted uptake of 3 H-leucine by the tuber disks of potato cv. Rishiri, but the inhibition rates caused by these fractions differed markedly. However, very high correlation was found between inhibition rates of 3 H-leucine uptake and sugar contents of these fractions. There was no difference in the inhibition rates between the zoosporial components of incompatible and compatible races, when the activities were expressed in terms of the sugar contents. The mycelial components of P. infestans extracted by the modified method of Lisker and Kuc which was used to extract phytoalexin elicitor from that of P. infestans, also had the same effect as the zoosporial components (A, B, and C-fraction) on 3 H-leucine uptake by the disks. C-fraction containing 15 μg of sugar per ml sufficed to inhibit 3 H-leucine uptake at the maximum rate, and the maximum rate of inhibition was attained within 2 hr after the zoosporial component (C-fraction containing 30 μg sugar/ml) was administered to the disks. (author)

Oxidative stress and enzymatic scavenging of superoxide radicals induced by solar UV-B radiation in Ulva canopies from southern Spain

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Kai Bischof

2003-09-01

Full Text Available The generation of reactive oxygen species (ROS and scavenging of the superoxide radical by superoxide dismutase (SOD was studied in mat-like canopies of the green macroalga Ulva rotundata Bliding in a tidal brine pond system in southern Spain. Artificial canopies were covered with different cut-off filters, generating different radiation conditions. ROS and SOD were assessed after three days of exposure. ROS induced lipid peroxidation depended on the position of individual thalli within the canopy and on radiation conditions. Samples exposed to the full solar spectrum were most affected, whereas samples either exposed to photosynthetically active radiation (PAR alone or UV radiation without PAR exhibited fewer peroxidation products. The activity of SOD appeared to be controlled by the impinging UV-A and UV-B radiation and also increased in response to oxidative stress. The results provide evidence for additive effects of high PAR and UV-B under field conditions and support the previously proposed hypothesis that UV-B effects are mediated by an inhibition of the xanthophyll cycle, which increases ROS production and, consequently, causes oxidative damage to components of the photosynthetic machinery, such as proteins and pigments.

Pythium insidiosum: An overview

NARCIS (Netherlands)

Gaastra, W.; Lipman, L.J.A.; De Cock, A.W.; Exel, T.K.; Pegge, R.B.; Scheurwater, J.; Vilela, R.; Mendoza, L.

2010-01-01

Pythium insidiosum is an oomycete pathogenic in mammals. The infection occurs mainly in tropical and subtropical areas, particularly in horses, dogs and humans. Infection is acquired through small wounds via contact with water that contains motile zoospores or other propagules (zoospores or hyphae).

Germination and growth of lettuce (Lactuca sativa) at low atmospheric pressure

Science.gov (United States)

Spanarkel, Robert; Drew, Malcolm C.

2002-01-01

The response of lettuce (Lactuca sativa L. cv. Waldmann's Green) to low atmospheric pressure was examined during the initial 5 days of germination and emergence, and also during subsequent growth to vegetative maturity at 30 days. Growth took place inside a 66-l-volume low pressure chamber maintained at 70 kPa, and plant response was compared to that of plants in a second, matching chamber that was at ambient pressure (approximately 101 kPa) as a control. In other experiments, to determine short-term effects of low pressure transients, plants were grown at ambient pressure until maturity and then subjected to alternating periods of 24 h of low and ambient atmospheric pressures. In all treatments the partial pressure of O2 was maintained at 21 kPa (approximately the partial pressure in air at normal pressure), and the partial pressure of CO2 was in the range 66.5-73.5 Pa (about twice that in normal air) in both chambers, with the addition of CO2 during the light phase. With continuous exposure to low pressure, shoot and root growth was at least as rapid as at ambient pressure, with an overall trend towards slightly greater performance at the lower pressure. Dark respiration rates were greater at low pressure. Transient periods at low pressure decreased transpiration and increased dark respiration but only during the period of exposure to low pressure. We conclude that long-term or short-term exposure to subambient pressure (70 kPa) was without detectable detriment to vegetative growth and development.

A relative contribution of carbon from green tide algae Cladophora glomerata and Ulva intestinalis in the coastal food webs in the Neva Estuary (Baltic Sea).

Science.gov (United States)

Golubkov, Sergey M; Berezina, Nadezhda A; Gubelit, Yulia I; Demchuk, Anna S; Golubkov, Mikhail S; Tiunov, Alexei V

2018-01-01

We analyzed stable isotope composition of carbon and nitrogen of suspended organic matter (seston) and tissues of macroalgae, macroinvertebrates and fish from the coastal area of the highly eutrophic Neva Estuary to test a hypothesis that organic carbon of macroalgae Cladophora glomerata and Ulva intestinalis produced during green tides may be among primary sources supporting coastal food webs. The Stable Isotope Bayesian mixing model (SIAR) showed that consumers poorly use organic carbon produced by macroalgae. According to the results of SIAR modeling, benthic macroinvertebrates and fish mostly rely on pelagic derived carbon as a basal resource for their production. Only some species of macroinvertebrates consumed macroalgae. Fish used this resource directly consuming zooplankton or indirectly via benthic macroinvertebrates. This was consistent with the results of the gut content analysis, which revealed a high proportion of zooplankton in the guts of non-predatory fish. Copyright © 2017. Published by Elsevier Ltd.

Evaluation of the cultivation of the lettuce (Lactuca sativa L. under organoponico and semi-protected systems

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Dania Bárbara Núñez Sosa

2015-03-01

Full Text Available The research was done in the organoponico at the Soil Laboratory in Matanzas. The objective was to evaluate the response of the of the lettuce (Lactuca sativa, L. cultivation under conditions of organoponic and Semi-protected cultivation systems. Two varieties were studied: Fomento 95 and Black Seeded Simpson (BSS. The random block design was used. The data were processed using the Statgraphic plus 5.1 package for WINDOWS. The total number of leaves, number of commercial leaves, diameter of bush, yield in kg/m2, total content of soluble proteins and carbohydrates were evaluated. In conclusion, the variety Fomento 95 showed a significant increment of the total number of leaves in the organoponico system and commercial leaves with respect to the semi-protected conditions; the BSS variety showed only significant differences in commercial leaves; no significant differences in yield for both varieties were reported under the studied conditions. The analysis showed that the total soluble carbohydrates and proteins content decreased significantly in both varieties under semi-protected conditions.

Ethanol Extract from Ulva prolifera Prevents High-Fat Diet-Induced Insulin Resistance, Oxidative Stress, and Inflammation Response in Mice

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Wei Song

2018-01-01

Full Text Available Ulva prolifera is the major causative species in the green tide, a serious marine ecological disaster, which bloomed in the Yellow Sea and the Bohai Sea of China. However, it is also a popular edible seaweed and its extracts exerts anti-inflammatory and antioxidant effects. The present study investigated the effects of ethanol extract of U. prolifera (EUP on insulin sensitivity, inflammatory response, and oxidative stress in high-fat-diet- (HFD- treated mice. HFD-treated mice obtained drinking water containing 2% or 5% EUP. The results showed that EUP supplementation significantly prevented HFD-induced weight gain of liver and fat. EUP supplementation also improved glucose tolerance and insulin resistance in HFD-treated mice. Moreover, EUP supplementation prevented the increased expression of genes involved in triglyceride synthesis and proinflammatory genes and the decreased expression of genes involved in fatty acid oxidation in liver of HFD-treated mice. Furthermore, EUP supplementation decreased reactive oxygen species content, while increasing glutathione content and glutathione peroxidase activity in HFD-treated mice. In conclusion, our results showed that EUP improved insulin resistance and had antilipid accumulation and anti-inflammatory and antioxidative effects on HFD-treated mice. We suggested that U. prolifera extracts may be regarded as potential candidate for the prevention of nonalcoholic fatty liver disease.

Cubic liquid crystalline nanoparticles containing a polysaccharide from Ulva fasciata with potent antihyperlipidaemic activity

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Azza A. Matloub

2018-02-01

Full Text Available The present study involves the preparation of cubic liquid crystalline nanoparticles (cubsomes for liver targeting to assess the potential of a formulated bioactive polysaccharide isolated from the hot aqueous extract of Ulva fasciata as an alternative natural agent with anti-hyperlipidaemic activity. Cubosomal nanoparticles were prepared by disrupting the cubic gel phase of the polysaccharide and water in the presence of a surfactant. Different lipid matrices and stabilizers were tested. All the formulations were in the nanosize range and showed sufficient negative charge to inhibit the aggregation of the cubosomes. Drug entrapment efficiencies (EEs% were determined and in vitro release studies were performed. Transmission electron microscopy (TEM and differential scanning calorimetry were used to analyze the loaded cubosomal nanoparticles containing glyceryl monostearate (GMO 2.25 g, poloxamer 407 (0.25 g and 50 mg of the polysaccharide. A preclinical study comparing the cubic liquid crystalline nanoparticles containing polysaccharide to fluvastatin as a reference drug in hyperlipidaemic rats was conducted. The rats treated with the polysaccharide- loaded cubosomes showed significant decreases in total cholesterol (TC, triglycerides (TG and total lipid (TL compared to the untreated HL rats. In addition, oxidative stress and antioxidant biomarkers were measured in the HL rats. Compared to the untreated HL rats, the cubosome treated rats showed a significant reduction in malondialdehyde (MDA, whereas insignificant changes were detected in nitric oxide (NO, glutathione (GSH levels and total antioxidant capacity (TAC. Further, vascular and intercellular adhesion molecules (VCAM, ICAM, and myeloperoxidase were demonstrated. A histopathological examination was conducted to study the alterations in histopathological lesions and to document the biochemical results. In conclusion, this study demonstrates the superiority of using a natural lipid

Immunomodulating activities of acidic sulphated polysaccharides obtained from the seaweed Ulva rigida C. Agardh.

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Leiro, José M; Castro, Rosario; Arranz, Jon A; Lamas, Jesús

2007-07-01

Water-soluble acidic polysaccharides from the cell walls of Ulva rigida are mainly composed of disaccharides that contain glucuronic acid and sulphated rhamnose. The structure of disaccharides resembles that of glycosaminoglycans (GAGs) as they both contain glucuronic acid and sulphated sugars. Glycosaminoglycans occur in the extracellular matrix of animal connective tissues but can also be produced by leucocytes at inflammatory sites. Certain types of GAGs can even activate macrophages and therefore the acidic polysaccharides from U. rigida probably modulate macrophage activity. In the present study, we evaluated the effects of U. rigida polysaccharides on several RAW264.7 murine macrophage activities, including expression of inflammatory cytokines and receptors, nitric oxide and prostaglandin E2 (PGE(2)) production, and nitric oxide synthase 2 (NOS-2) and cyclooxygenase-2 (COX-2) gene expression. U. rigida acidic polysaccharides induced a more than two-fold increase in the expression of several chemokines (chemokine (C motif) ligand 1, chemokine (C-X-C motif) ligand 12, chemokine (C-C motif) ligand 22 and chemokine (C-X-C motif) ligand 14 (Cxcl14)) and in the expression of IL6 signal transducer and IL12 receptor beta 1. Incubation of macrophages with U. rigida polysaccharides also induced an increase in nitrite production, although this effect decreased considerably after desulphation of polysaccharides, suggesting that the sulphate group is important for the stimulatory capacity of these molecules. U. rigida polysaccharides also stimulated macrophage secretion of PGE(2) and induced an increase in COX-2 and NOS-2 expression. The results indicate that U. rigida acid polysaccharide can be used as an experimental immunostimulant for analysing inflammatory responses related to macrophage functions. In addition, these polysaccharides may also be of clinical interest for modifying certain macrophage activities in diseases where macrophage function is impaired or needs

Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

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Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

2017-08-01

Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

Pharmacological and phytochemical screening of Palestinian traditional medicinal plants Erodium laciniatum and Lactuca orientalis.

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Jaradat, Nidal; AlMasri, Motasem; Zaid, Abdel Naser; Othman, Dua'a Ghazi

2017-09-01

Various epidemiological studies showed that herbal remedies containing polyphenols may protect against various diseases such as cancers, vascular diseases and inflammatory pathologies. Currently, such groups of bioactive compounds have become a subject of many antimicrobials and antioxidant investigations. Accordingly, the current study aimed to conduct biological and phytochemical screening for two Palestinian traditional medicinal plants, Erodium laciniatum and Lactuca orientalis. Current plants phytoconstituents and their antioxidant activities were evaluated by using standard phytochemical methods; meanwhile, antimicrobial activities were estimated by using several types of American Type Culture Collection and multidrug resistant clinical isolates by using agar diffusion well-variant, agar diffusion disc-variant and broth microdilution methods. Phytochemical screenings showed that L. orientalis and E. laciniatum contain mixtures of secondary and primary metabolites Moreover, total flavonoid, tannins and phenols content in E. laciniatum extract were higher than the L. orientalis extracts with almost the same antioxidant potentials. Additionally, both plants organic and aqueous extracts showed various potentials of antimicrobial activity Conclusions: Overall, the studied species have a mixture of phytochemicals, flavonoids, phenols and tannins also have antioxidant and antimicrobial activities which approved their folk uses in treatments of infectious and Alzheimer diseases and simultaneously can be used as therapeutic agents in the pharmaceutical industries.

The Influence of biol in the crop yield of Lactuca sativa L. variety Iceberg

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Pomboza-Tamaquiza Pablo

2016-11-01

Full Text Available The objective of the research was to assess the influence of biol enriched with efficient micro-organisms, in the ecological cultivation of Lactuca sativa L (lettuce variety "Iceberg". The field test was carried out on the farm of Querochaca, Faculty of Sciences Agriculture, of the Technical University of Ambato. The studied factors were doses of biol (2%, 4% and 6% and frequencies of application (8 and 15 days, I know used the experimental design of complete blocks at random, with factorial arrangement of 3x2 1 with three repetitions. We evaluated: plant height, diameter of the main stem, days to harvest, weight and diameter of the bud commercial, performance in kg/plot neta and performance in kg/experimental unit, conducted the significance test of Duncan to 5%. The results showed that the dose of 6 per cent applied every 15 days treatment D3F2, contributed to the larger diameter of the bud commercial (25.9 cm; the greater weight of cogollo commercial (1.14 kg and the higher performance (549 kg/experimental unit. This suggests that the implementation of biol can be an important ecological alternative to fertilize organic farming as the lettuce by reducing the use of fertilizers in chemical synthesis and production costs.

Carbon dioxide evolution and temperature factors in early growth of plastic mulched plants. [Cucumis melo L. var. reticulatus; Lactuca sativa L. var. crispa

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Betts, C.; Ruf, R.H. Jr.

1966-01-01

Cantaloupe (Cucumis melo L. var. reticulatus) and lettuce (Lactuca sativa L. var. crispa) were grown in the greenhouse in redwood boxes with bare and plastic mulched soil. Soil temperature in the bare boxes was equated to the plastic mulch with buried temperature coils. Bottled CO/sub 2/ was used to bring the concentration around the plants in bare soil up to the concentration around mulched plants. Carbon dioxide was sampled in leaf canopy. The temperature treatment increased the yields of the bare soil so that they were comparable to those of the plastic mulched soil. Yields from the soil with the auxiliary CO/sub 2/ were lower than those of the mulched treatment.

An evaluation of the toxicity and bioaccumulation of bismuth in the coastal environment using three species of macroalga

International Nuclear Information System (INIS)

Kearns, James; Turner, Andrew

2016-01-01

Bismuth is a heavy metal whose biogeochemical behaviour in the marine environment is poorly defined. In this study, we exposed three different species of macroalga (the chlorophyte, Ulva lactuca, the phaeophyte, Fucus vesiculosus, and the rhodophyte, Chondrus crispus) to different concentrations of Bi (up to 50 μg L −1 ) under controlled, laboratory conditions. After a period of 48-h, the phytotoxicity of Bi was measured in terms of chlorophyll fluorescence quenching, and adsorption and internalisation of Bi determined by ICP after EDTA extraction and acid digestion, respectively. For all algae, both the internalisation and total accumulation of Bi were proportional to the concentration of aqueous metal. Total accumulation followed the order: F. vesiculosus > C. crispus > U. lactuca; with respective accumulation factors of about 4200, 1700 and 600 L kg −1 . Greatest internalisation (about 33% of total accumulated Bi) was exhibited by C. crispus, the only macroalga to display a phytotoxic response in the exposures. A comparison of the present results with those reported in the literature suggests that Bi accumulation by macroalgae is significantly lower than its accumulation by marine plankton (volume concentration factors of 10 5 to 10 7 ), and that the phytotoxicity of Bi is low relative to other heavy metals like Ag and Tl. - Highlights: • Very little is understood about the biogeochemistry of bismuth. • We exposed three species of coastal macroalga to variable concentrations of Bi. • Greatest accumulation was exhibited by Fucus vesiculosus. • Greatest internalisation was exhibited by Chondus crispus. • C. crispus was the only macroalga to display a toxic response. - Bismuth is accumulated by three species of marine macroalga but exhibits only moderate toxicity to the rhodophyte, Chondrus crispus.

Growing different Lactuca genotypes aeroponically within a tropical greenhouse – Cool rootzone temperatures decreased rootzone ethylene concentrations and increased shoot growth

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Tsui Wei CHOONG

2016-09-01

Full Text Available Temperate crops cannot grow well in the tropics without rootzone cooling. As cooling increased production costs, this experiment aimed to study the growth of various Lactuca genotypes and propose possible ways of reducing these costs, without compromising productivity. A recombinant inbred line (RIL of lettuce and its parental lines (L. serriola and L. sativa ‘Salinas’ were grown aeroponically in a tropical greenhouse under 24 C cool (C or warm fluctuating 30-36 C ambient (A rootzone temperature (RZT. Their roots were misted with Netherlands standard nutrient solution for 1 min, at intervals of either 5 min (A5, C5 or 10 min (A10, C10 in attempting to reduce electricity consumption and production costs. Lower mortality and higher productivity were observed in all genotypes when grown in C-RZT. Higher shoot fresh weight was observed under C5 than C10, for the RIL and L. serriola. Since ‘Salinas’ had similar shoot fresh weight at both C-RZ treatments, this may indicate it is more sensitive to RZT than water availability. Under A-RZ treatments, higher carotenoid content, with correspondingly higher nonphotochemical quenching, was observed in A10 for the RIL and ‘Salinas’. Further, total chlorophyll content was also highest at this RZ treatment for the RIL though photochemical quenching was contrastingly the lowest. Cumulatively, productivity was compromised at A10 as the RIL seemed to prioritize photoprotection over efficiency in photosynthesis, under conditions of higher RZT and lower water availability. Generally, higher RZ ethylene concentrations accumulated in A10 and C10 than A5 and C5, respectively – probably due to spray frequency exerting a greater effect on RZ ethylene accumulation than RZT. In the C5 RZ treatment, lowest RZ ethylene concentration corresponded with highest shoot fresh weight. As such, further research on ethylene (insensitivity and water use efficiency could be conducted to identify Lactuca cultivars

Evidence of coexistence of C₃ and C₄ photosynthetic pathways in a green-tide-forming alga, Ulva prolifera.

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Jianfang Xu

Full Text Available Ulva prolifera, a typical green-tide-forming alga, can accumulate a large biomass in a relatively short time period, suggesting that photosynthesis in this organism, particularly its carbon fixation pathway, must be very efficient. Green algae are known to generally perform C₃ photosynthesis, but recent metabolic labeling and genome sequencing data suggest that they may also perform C₄ photosynthesis, so C₄ photosynthesis might be more wide-spread than previously anticipated. Both C₃ and C₄ photosynthesis genes were found in U. prolifera by transcriptome sequencing. We also discovered the key enzymes of C₄ metabolism based on functional analysis, such as pyruvate orthophosphate dikinase (PPDK, phosphoenolpyruvate carboxylase (PEPC, and phosphoenolpyruvate carboxykinase (PCK. To investigate whether the alga operates a C₄-like pathway, the expression of rbcL and PPDK and their enzyme activities were measured under various forms and intensities of stress (differing levels of salinity, light intensity, and temperature. The expression of rbcL and PPDK and their enzyme activities were higher under adverse circumstances. However, under conditions of desiccation, the expression of rbcL and ribulose-1, 5-biphosphate carboxylase (RuBPCase activity was lower, whereas that of PPDK was higher. These results suggest that elevated PPDK activity may alter carbon metabolism and lead to a partial operation of C₄-type carbon metabolism in U. prolifera, probably contributing to its wide distribution and massive, repeated blooms in the Yellow Sea.

Nivel de contaminación enteroparasitaria de lechugas (Lactuca Sativa) irrigadas con aguas del Río Rímac para consumo humano en la zona de Carapongo.

OpenAIRE

Palacios Morales, Félix Nicolás

2010-01-01

Objetivo: El presente estudio tuvo como objetivo determinar el nivel de la contaminación enteroparasitaria de lechugas para consumo humano irrigadas con aguas servidas del río Rímac en poscosecha. Metodología: Se estableció tres zonas de estudio Z-1 curva del cerro Cuncacucho, Z-2 puente o mercado de Carapongo a 50 m de rivera del río y Z-3 paradero Portillo a 50 m de la ribera del río Las muestras de lechuga, (Lactuca sativa), fueron tomadas in situ en número de dos unidades, de las cuales s...

Allelopathic Activity of Extracts from Different Brazilian Peanut (Arachis hypogaea L.) Cultivars on Lettuce (Lactuca sativa) and Weed Plants

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Garcia, R.; Simas, N. K.

2017-01-01

Peanut (Arachis hypogaea L.) is the fourth most consumed oleaginous plant in the world, producing seeds with high contents of lipids, proteins, vitamins, and carbohydrates. Biological activities of different extracts of this species have already been evaluated by many researchers, including antioxidant, antitumoral, and antibacterial. In this work, the allelopathic activity of extracts from different Brazilian peanut cultivars against lettuce (Lactuca sativa) and two weed plants (Commelina benghalensis and Ipomoea nil) was studied. Aerial parts, roots, seeds, and seed coats were used for the preparation of crude extracts. Seed extract partitioning was performed with n-hexane, dichloromethane, ethyl acetate, n-butanol, and aqueous residue. Germination and growth of hypocotyls and rootlets were evaluated after one and five days of incubation with plant extracts, respectively. Crude seed extract and its dichloromethanic partition displayed highest allelopathic activity. These results contribute for the study of new potential natural herbicides. PMID:28396881

Allelopathic Activity of Extracts from Different Brazilian Peanut (Arachis hypogaea L.) Cultivars on Lettuce (Lactuca sativa) and Weed Plants.

Science.gov (United States)

Casimiro, G S; Mansur, E; Pacheco, G; Garcia, R; Leal, I C R; Simas, N K

2017-01-01

Peanut ( Arachis hypogaea L.) is the fourth most consumed oleaginous plant in the world, producing seeds with high contents of lipids, proteins, vitamins, and carbohydrates. Biological activities of different extracts of this species have already been evaluated by many researchers, including antioxidant, antitumoral, and antibacterial. In this work, the allelopathic activity of extracts from different Brazilian peanut cultivars against lettuce (Lactuca sativa) and two weed plants ( Commelina benghalensis and Ipomoea nil ) was studied. Aerial parts, roots, seeds, and seed coats were used for the preparation of crude extracts. Seed extract partitioning was performed with n -hexane, dichloromethane, ethyl acetate, n -butanol, and aqueous residue. Germination and growth of hypocotyls and rootlets were evaluated after one and five days of incubation with plant extracts, respectively. Crude seed extract and its dichloromethanic partition displayed highest allelopathic activity. These results contribute for the study of new potential natural herbicides.

Synthesis of Biodiesel from the Oily Content of Marine Green Alga Ulva fasciata

International Nuclear Information System (INIS)

Khan, A. M.; Fatima, N.

2015-01-01

The present study is focused on the chemical transformation of oils derived from the marine green alga Ulva fasciata Delile to biodiesel. The transesterification of algal oil was performed with a variety of alcohols using Na metal and NaOH as catalysts. Transesterification of algal oil by mechanical stirring yielded significant biodiesel within an hour at 60 degree C with NaOH and at room temperature with Na metal. In addition, microwave irradiated transesterification produced significant amount of biodiesel with NaOH and Na metal within 1-5 minutes. However, reaction of sodium metal in microwave oven was highly exothermic and uncontrollable that could also damage the radiation source. The reactivity order of alcohols was found to be methanol > ethanol > benzyl alcohol > 1-propanol > 1-butanol > 1-pentanol > 1-hexanol > 2-propanol. Isopropyl alcohol was found to be least reactive due to steric hindrance. Benzyl alcohol was found to be more reactive than 1-propyl alcohol due to the electron withdrawing effect of benzene ring. The highest % conversion of FAME and FAEE were found to be 97% and 98% respectively using Na metal through mechanical stirring. Biodiesel production was confirmed by thin layer chromatography (TLC). Furthermore, the fuel properties including density, kinematics viscosity, high heating value, acid value, free fatty acid (%), cloud point and pour point of U. fasciata oil and all the esters were determined and compared with the standard limits of biodiesel. Fatty acid methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 1-pentyl and 1-hexyl esters showed the fuel properties within the biodiesel standard limits therefore all of them were considered as the substitute of biodiesel. On the other hand, the fuel properties of benzyl ester were found to be above the limits of biodiesel specifications and thus it could not be considered as biodiesel. This research article will be helpful to overcome the current challenges of energy crisis, global warming and

Preparation of novel alginate based anion exchanger from Ulva japonica and its application for the removal of trace concentrations of fluoride from water.

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Paudyal, Hari; Pangeni, Bimala; Inoue, Katsutoshi; Kawakita, Hidetaka; Ohto, Keisuke; Ghimire, Kedar Nath; Alam, Shafiq

2013-11-01

A green seaweed, Ulva japonica, was modified by loading multivalent metal ions such as Zr(IV) and La(III) after CaCl2 cross-linking to produce metal loaded cross-linked seaweed (M-CSW) adsorbents, which were characterized by elemental analysis, functional groups identification, and metal content determination. Maximum sorption potential for fluoride was drastically increased after La(III) and Zr(IV) loading, which were evaluated as 0.58 and 0.95 mmol/g, respectively. Loaded fluoride was quantitatively desorbed by using dilute alkaline solution for its regeneration. Mechanism of fluoride adsorption was inferred in terms of ligand exchange reaction between hydroxyl ion on co-ordination sphere of the loaded metal ions of M-CSW and fluoride ion in aqueous solution. Application of M-CSW for the treatment of actual waste plating solution exhibited successful removal of fluoride to clear the effluent and environmental standards in Japan, suggesting high possibility of its application for the treatment of fluoride rich waste water. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Sargassum Frogfish (Histrio histrio Linnaeus) observed in mangroves in St. John, US Virgin Islands

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Rogers, C.S.; Pietsch, T.W.; Randall, J.E.; Arnold, R.J.

2010-01-01

The Sargassum Frogfish (Histrio histrio), the only pelagic member of the frogfish family Antennariidae, is considered an obligate associate of floating mats of the brown algae Sargassum natans and S. fluitans (Adams 1960; Dooley 1972; Pietsch and Grobecker 1987). Between February and April 2010, 20 of these fish were observed in three mangrove-fringed bays in Virgin Islands Coral Reef National Monument, St. John, US Virgin Islands. All of them were clinging to clumps of the red alga Acanthophora spicifera growing on the submerged prop roots of red mangrove trees (Rhizophora mangle) distributed along an estimated total of 2,160 mof shoreline (Fig. 1). All of the fish were at a depth of less than 0.5 meters. Two individuals were seen on one prop root, but the other 18 were solitary. Their estimated standard lengths ranged from about 20 to 100 mm. Littler and Littler (2000, p. 295) published a photograph of one individual in blades of the green alga Ulva lactuca growing on a prop root in Belize. This is the first report of the Sargassum Frogfish living in association with attached algae.

Effect of corn steep liquor on lettuce root rot (Fusarium oxysporum f.sp. lactucae) in hydroponic cultures.

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Chinta, Yufita D; Kano, Kazuki; Widiastuti, Ani; Fukahori, Masaru; Kawasaki, Shizuka; Eguchi, Yumi; Misu, Hideyuki; Odani, Hiromitsu; Zhou, Songying; Narisawa, Kazuhiko; Fujiwara, Kazuki; Shinohara, Makoto; Sato, Tatsuo

2014-08-01

Recent reports indicate that organic fertilisers have a suppressive effect on the pathogens of plants grown under hydroponic systems. Furthermore, microorganisms exhibiting antagonistic activity to diseases have been observed in organic hydroponic systems. This study evaluated the effect of corn steep liquor (CSL) on controlling lettuce root rot disease [Fusarium oxysporum f.sp. lactucae (FOL)] in a hydroponic system. The effect of CSL and Otsuka A (a chemical fertiliser) on the inhibition of FOL in terms of mycelial growth inhibition was tested in vivo. Addition of CSL suppressed FOL infection rates. CSL inhibited FOL infection by 26.3-42.5% from 2 days after starting incubation. In comparison, Otsuka A inhibited FOL growth by 5.5-19.4%. In addition, four of 10 bacteria isolated from the nutrient media containing CSL exhibited inhibition zones preventing FOL mycelial growth. We found that CSL suppressed FOL in lettuce via its antifungal and biostimulatory effects. We suggest that activation of beneficial microorganisms present in CSL may be used to decrease lettuce root rot disease and contribute to lettuce root growth. © 2014 Society of Chemical Industry.

Cell cycles and proliferation patterns in Haematococcus pluvialis

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Zhang, Chunhui; Liu, Jianguo; Zhang, Litao

2017-09-01

Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation; far less attention has been paid to cell cycles and proliferation patterns. The purpose of this study was to clarify cell cycles and proliferation patterns in H. pluvialis microscopically using a camera and video recorder system. The complicated life history of H. pluvialis can be divided into two stages: the motile stage and the non-motile stage. All the cells can be classified into forms as follows: motile cell, nonmotile cell, zoospore and aplanospore. The main cell proliferation, both in the motile phase and non-motile phase in H. pluvialis, is by asexual reproduction. Under normal growth conditions, a motile cell usually produces two, sometimes four, and exceptionally eight zoospores. Under unfavorable conditions, the motile cell loses its flagella and transforms into a non-motile cell, and the non-motile cell usually produces 2, 4 or 8 aplanospores, and occasionally 20-32 aplanospores, which further develop into non-motile cells. Under suitable conditions, the non-motile cell is also able to release zoospores. The larger non-motile cells produce more than 16 zoospores, and the smaller ones produce 4 or 8 zoospores. Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase. There is, as yet, no convincing direct evidence for sexual reproduction.

Phytohormone profile in Lactuca sativa and Brassica oleracea plants grown under Zn deficiency.

Science.gov (United States)

Navarro-León, Eloy; Albacete, Alfonso; Torre-González, Alejandro de la; Ruiz, Juan M; Blasco, Begoña

2016-10-01

Phytohormones, structurally diverse compounds, are involved in multiple processes within plants, such as controlling plant growth and stress response. Zn is an essential micronutrient for plants and its deficiency causes large economic losses in crops. Therefore, the purpose of this study was to analyse the role of phytohormones in the Zn-deficiency response of two economically important species, i.e. Lactuca sativa and Brassica oleracea. For this, these two species were grown hydroponically with different Zn-application rates: 10 μM Zn as control and 0.1 μM Zn as deficiency treatment and phytohormone concentration was determined by U-HPLC-MS. Zn deficiency resulted in a substantial loss of biomass in L. sativa plants that was correlated with a decline in growth-promoting hormones such as indole-3-acetic acid (IAA), cytokinins (CKs), and gibberellins (GAs). However these hormones increased or stabilized their concentrations in B. oleracea and could help to maintain the biomass in this species. A lower concentration of stress-signaling hormones such as ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA) and jasmonic acid (JA) and also CKs might be involved in Zn uptake in L. sativa while a rise in GA4, isopentenyl adenine (iP), and ACC and a fall in JA and SA might contribute to a better Zn-utilization efficiency (ZnUtE), as observed in B. oleracea plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lettuce (Lactuca sativa L. seedling production with different sources of phosphate and phosphate solubilizing microorganisms / Produção de mudas de alface (Lactuca sativa L. em presença de diferentes fontes fosfatadas e microrganismos

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Germano Nunes Silva Filho

2009-10-01

Full Text Available The objective of this work was to evaluate the behaviour of phosphate solubilizing microorganisms (fungus: 310A, 061, 062 e 251, bacterias 163, 160 e 161 in promoting nutrition and growth of lettuce(Lactuca sativa L. seedlings cultivated in trays with sterilized substrate fertilized and phosphates source. A randomized completely design was used, with a factorial 4x8 scheme (four treatments with phosphate nutrition and inoculated with eight phosphate solubilizing microorganisms and four replications. Each replication was made of 10 cells. The experiment was evaluated 35 days after planting for dry matter, P percentage and total phosphorus of above ground parts. The triple super phosphate (SFT had better results than the others, including the control treatment, in all analyzed parameters. On the dry matter production, it was observed negative effect from inoculation in five treatments fertilized with SFT. There was no effect of isolates on the phosphorus content values. In the values of total phosphorus, the isolates 061, 062 e 163 increased the parameter values on the fertilized treatment with SFT. The natural phosphates presented low efficiency when compared to dissolvable fertilizer on the availability of phosphorus to the plants.O objetivo deste trabalho foi avaliar o comportamento de microrganismos solubilizadores de fosfatos (fungos: 310A, 061, 062 e 251; bactérias: 163, 160 e 161 na promoção da nutrição e crescimento de mudas de alface (Lactuca sativa L., cultivadas em bandejas com substrato esterilizado e adubadas com fontes fosfatadas. Foi utilizado um delineamento inteiramente casualizado, arranjo fatorial 4 x 8 (quatro tratamentos de adubação fosfatada e oito tratamentos de inoculação microrganismos solubilizadores de fosfatos com quatro repetições por isolado. Cada repetição foi constituída de 10 células. Aos 35 dias de cultivo, as plantas foram colhidas avaliando-se a matéria seca, porcentagem de P e P total da parte a

Heavy metals deposited in the culture of lettuce (Lactuca sativa L.) by the influence of vehicular traffic in Pernambuco, Brazil.

Science.gov (United States)

França, Fernanda C S S; Albuuerque, Adriana M A; Almeida, Amanda C; Silveira, Patrícia B; Filho, Crescêncio A; Hazin, Clovis A; Honorato, Eliane V

2017-01-15

Currently one of the main sources of atmospheric pollution identified in urban centers is derived from both industrial and motor vehicle emissions. These pollutants can be adsorbed to particulate matter which is present in the air or deposited in the soil and plants, eventually reaching the human food chain. In this context, the present study aimed to determine the concentration of metals such as Cu, Pb, Cd, Ni and Zn in two subspecies of Lactuca sativa L. and in the soil from were lettuce samples were collected. The results for the soil samples analyzed show a possible contamination by Pb with concentration values as high as 140mg.kg(-1), which are above the Brazilian standards defined by Resolution CONAMA 420/2009 (Brazilian Environmental Council). However, the values found in the lettuce itself reveal that it is still suitable for consumption. Copyright © 2016. Published by Elsevier Ltd.

Hybridization rates between lettuce (Lactuca sativa) and its wild relative (L. serriola) under field conditions.

Science.gov (United States)

D'Andrea, Luigi; Felber, François; Guadagnuolo, Roberto

2008-01-01

Hybridization and introgression between crops and wild relatives may have important evolutionary and ecological consequences such as gene swamping or increased invasiveness. In the present study, we investigated hybridization under field conditions between crop lettuce (Lactuca sativa) and its wild relative prickly lettuce (L. serriola), two cross-compatible, predominantly autogamous and insect pollinated species. In 2003 and 2004, we estimated the rates of hybridization between L. sativa and L. serriola in close-to-reality field experiments carried out in two locations of Northern Switzerland. Seeds set by the experimental wild plants were collected and sown (44 352 in 2003 and 252 345 in 2004). Progeny was screened morphologically for detecting natural hybrids. Prior to the experiment, specific RAPD markers were used to confirm that morphological characters were reliable for hybrid identification. Hybridization occurred up to the maximal distance tested (40 m), and hybridization rates varied between 0 to 26%, decreasing with distance. More than 80% of the wild plants produced at least one hybrid (incidence of hybridization, IH) at 0 m and 1 m. It equaled 4 to 5% at 40 m. In sympatric crop-wild populations, cross-pollination between cultivated lettuce and its wild relative has to be seen as the rule rather than the exception for short distances.

Induction of sporulation and the influence of time, temperature, and inoculum size on growth in two species of aquatic fungi (Saprolegniales)

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Bailey, T.A.; Bradford, K.; Bland, C.E.

1990-01-01

Because the infective stage of most mycoses of aquatic organisms is the zoospore, we attempted to establish optimum conditions under which zoospores could be produced for use in antifungal testing. Optimum sporulation time, incubation time, inoculum size, and growth temperature were determined for each oftwo saprolegniaceous fungi, Achlya flagellata Coker and Saprolegnia hypogyna (Pringsheim) de Bary. Both species produced the largest number of zoospores after 18 hours (51.7 spores/ml for A. jlagellata and 848.0 spores/ml for S. hypogyna), and yielded maximum growth after 48 hours at 22 'C. The recommended test inoculum size for S. hypogyna (5,600 spores/ml was nearly three times that for A. flagellata (2,000 spores/ml),

Sulphated Polysaccharides from Ulva clathrata and Cladosiphon okamuranus Seaweeds both Inhibit Viral Attachment/Entry and Cell-Cell Fusion, in NDV Infection

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José Alberto Aguilar-Briseño

2015-01-01

Full Text Available Sulphated polysaccharides (SP extracted from seaweeds have antiviral properties and are much less cytotoxic than conventional drugs, but little is known about their mode of action. Combination antiviral chemotherapy may offer advantages over single agent therapy, increasing efficiency, potency and delaying the emergence of resistant virus. The paramyxoviridae family includes pathogens causing morbidity and mortality worldwide in humans and animals, such as the Newcastle Disease Virus (NDV in poultry. This study aims at determining the antiviral activity and mechanism of action in vitro of an ulvan (SP from the green seaweed Ulva clathrata, and of its mixture with a fucoidan (SP from Cladosiphon okamuranus, against La Sota NDV strain. The ulvan antiviral activity was tested using syncytia formation, exhibiting an IC50 of 0.1 μg/mL; ulvan had a better anti cell-cell spread effect than that previously shown for fucoidan, and inhibited cell-cell fusion via a direct effect on the F0 protein, but did not show any virucidal effect. The mixture of ulvan and fucoidan showed a greater anti-spread effect than SPs alone, but ulvan antagonizes the effect of fucoidan on the viral attachment/entry. Both SPs may be promising antivirals against paramyxovirus infection but their mixture has no clear synergistic advantage.

Sulphated polysaccharides from Ulva clathrata and Cladosiphon okamuranus seaweeds both inhibit viral attachment/entry and cell-cell fusion, in NDV infection.

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Aguilar-Briseño, José Alberto; Cruz-Suarez, Lucia Elizabeth; Sassi, Jean-François; Ricque-Marie, Denis; Zapata-Benavides, Pablo; Mendoza-Gamboa, Edgar; Rodríguez-Padilla, Cristina; Trejo-Avila, Laura María

2015-01-26

Sulphated polysaccharides (SP) extracted from seaweeds have antiviral properties and are much less cytotoxic than conventional drugs, but little is known about their mode of action. Combination antiviral chemotherapy may offer advantages over single agent therapy, increasing efficiency, potency and delaying the emergence of resistant virus. The paramyxoviridae family includes pathogens causing morbidity and mortality worldwide in humans and animals, such as the Newcastle Disease Virus (NDV) in poultry. This study aims at determining the antiviral activity and mechanism of action in vitro of an ulvan (SP from the green seaweed Ulva clathrata), and of its mixture with a fucoidan (SP from Cladosiphon okamuranus), against La Sota NDV strain. The ulvan antiviral activity was tested using syncytia formation, exhibiting an IC50 of 0.1 μg/mL; ulvan had a better anti cell-cell spread effect than that previously shown for fucoidan, and inhibited cell-cell fusion via a direct effect on the F0 protein, but did not show any virucidal effect. The mixture of ulvan and fucoidan showed a greater anti-spread effect than SPs alone, but ulvan antagonizes the effect of fucoidan on the viral attachment/entry. Both SPs may be promising antivirals against paramyxovirus infection but their mixture has no clear synergistic advantage.

Di-and tri-hydroxylated Kaurane derivatives from microbial transformation of Ent-Kaur-16-En-19-Ol by Cephalosporium aphidicola and their allelopathic activity on Lactuca sativa (lettuce)

Energy Technology Data Exchange (ETDEWEB)

Rocha, D.; Takahashi, J.A.; Boaventura, M.A.D. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Quimica], e-mail: dianadb@netuno.lcc.ufmg.br

2009-01-15

The use of microorganisms to induce chemical modifications in organic molecules is a very useful tool in organic synthesis, to obtain biologically active substances. The fungus Cephalosporium aphidicola is known by its ability to hydroxylate several skeleton positions of many classes of organic compounds. In this work, the microbial transformation of ent-kaur-16-en-19-01 (1) by C. aphidicola, afforded two hydroxylated compounds, ent-kauran-16{beta},19-diol (2) and ent-kauran-16{beta},17,19-triol (3). Their structures were established by 1D and 2D-NMR studies. Both compounds were tested for their action on the growth of radical and shoot of Lactuca sativa. (author)

Di-and tri-hydroxylated Kaurane derivatives from microbial transformation of Ent-Kaur-16-En-19-Ol by Cephalosporium aphidicola and their allelopathic activity on Lactuca sativa (lettuce)

International Nuclear Information System (INIS)

Rocha, D.; Takahashi, J.A.; Boaventura, M.A.D.

2009-01-01

The use of microorganisms to induce chemical modifications in organic molecules is a very useful tool in organic synthesis, to obtain biologically active substances. The fungus Cephalosporium aphidicola is known by its ability to hydroxylate several skeleton positions of many classes of organic compounds. In this work, the microbial transformation of ent-kaur-16-en-19-01 (1) by C. aphidicola, afforded two hydroxylated compounds, ent-kauran-16β,19-diol (2) and ent-kauran-16β,17,19-triol (3). Their structures were established by 1D and 2D-NMR studies. Both compounds were tested for their action on the growth of radical and shoot of Lactuca sativa. (author)

Surfactant assisted disperser pretreatment on the liquefaction of Ulva reticulata and evaluation of biodegradability for energy efficient biofuel production through nonlinear regression modelling.

Science.gov (United States)

Kumar, M Dinesh; Tamilarasan, K; Kaliappan, S; Banu, J Rajesh; Rajkumar, M; Kim, Sang Hyoun

2018-05-01

The present study aimed to increase the disintegration potential of marine macroalgae, (Ulva reticulata) through chemo mechanical pretreatment (CMP) in an energy efficient manner. By combining surfactant with disperser, the specific energy input was considerably reduced from 437.1 kJ/kg TS to 264.9 kJ/kg TS to achieve 10.7% liquefaction. A disperser rpm (10,000), pretreatment time (30 min) and tween 80 dosage (21.6 mg/L) were considered as an optimum for effective liquefaction of algal biomass. CMP was designated as an appropriate pretreatment resulting in a higher soluble organic release 1250 mg/L, respectively. Anaerobic fermentation results revealed that the volatile fatty acid (VFA) concentration was doubled (782 mg/L) in CMP when compared to mechanical pretreatment (MP) (345 mg/L). CMP pretreated algal biomass was considered as the suitable for biohydrogen production with highest H 2 yield of about 63 mL H 2 /g COD than (MP) (45 mL H 2 /g COD) and control (10 mL H 2 /g COD). Copyright © 2018 Elsevier Ltd. All rights reserved.

4,4,4-trifluoro-3-(indole-3-)butyric acid promotes root elongation in Lactuca sativa independent of ethylene synthesis and pH

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Zhang, Nenggang; Hasenstein, Karl H.

2002-01-01

We studied the mode of action of 4,4,4-trifluoro-3- (indole-3-) butyric acid (TFIBA), a recently described root growth stimulator, on primary root growth of Lactuca sativa L. seedlings. TFIBA (100 micromoles) promoted elongation of primary roots by 40% in 72 h but inhibited hypocotyl growth by 35%. TFIBA induced root growth was independent of pH. TFIBA did not affect ethylene production, but reduced the inhibitory effect of ethylene on root elongation. TFIBA promoted root growth even in the presence of the ethylene biosynthesis inhibitor L-alpha-(2-aminoethoxyvinyl)glycine. TFIBA and the ethylene-binding inhibitor silver thiosulphate (STS) had a similar effect on root elongation. The results indicate that TFIBA-stimulated root elongation was neither pH-dependent nor related to inhibition of ethylene synthesis, but was possibly related to ethylene action.

Root adaptation and ion selectivity affects the nutritional value of salt-stressed hydroponically grown baby-leaf Nasturtium officinale and Lactuca sativa

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Juan A. Fernández

2016-12-01

Full Text Available The response of watercress (Nasturtium officinale L. to salinity has been scarcely addressed in literature despite its growing importance in the baby-leaf market and its wide cultivation in salt-affected agricultural regions. This work evaluates the effect of salinity (2.5, 5 and 10 dS m-1 on productive and quality features of watercress compared with another crop widely cultivated for the baby-leaf sector (lettuce, Lactuca sativa. In watercress, a linear relationship (R2=0.75 was observed between yield decrease and Cl– accumulation in leaves, whereas yield was not affected by salinity in lettuce. NaCl application increased Na+ accumulation at the expense of Ca2+ uptake in the leaf tissues of both crops, but also of K+ in watercress. Health-related features were improved by salinity (e.g. increased phenolics and reduced nitrates, especially in watercress, with limited sensorial quality evaluation effects.

Uptake and phytotoxic effect of benzalkonium chlorides in Lepidium sativum and Lactuca sativa.

Science.gov (United States)

Khan, Adnan Hossain; Libby, Mark; Winnick, Daniel; Palmer, John; Sumarah, Mark; Ray, Madhumita B; Macfie, Sheila M

2018-01-15

Cationic surfactants such as benzalkonium chlorides (BACs) are used extensively as biocides in hospitals, food processing industries, and personal care products. BACs have the potential to reach the rooting zone of crop plants and BACs might thereby enter the food chain. The two most commonly used BACs, benzyl dimethyl dodecyl ammonium chloride (BDDA) and benzyl dimethyl tetradecyl ammonium chloride (BDTA), were tested in a hydroponic system to assess the uptake by and phytotoxicity to lettuce (Lactuca sativa L.) and garden cress (Lepidium sativum L.). Individually and in mixture, BACs at concentrations up to 100 mg L -1 did not affect germination; however, emergent seedlings were sensitive at 1 mg L -1 for lettuce and 5 mg L -1 for garden cress. After 12 d exposure to 0.25 mg L -1 BACs, plant dry weight was reduced by 68% for lettuce and 75% for garden cress, and symptoms of toxicity (necrosis, chlorosis, wilting, etc.) were visible. High performance liquid chromatography-mass spectroscopy analysis showed the presence of BACs in the roots and shoots of both plant species. Although no conclusive relationship was established between the concentrations of six macro- or six micro-nutrients, growth inhibition or BAC uptake, N and Mg concentrations in BAC-treated lettuce were 50% lower than that of control, indicating that BACs might induce nutrient deficiency. Although bioavailability of a compound in hydroponics is significantly higher than that in soil, these results confirm the potential of BACs to harm vascular plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biochemical study of leaf browning in minimally processed leaves of lettuce (Lactuca sativa L. var. acephala).

Science.gov (United States)

Degl'Innocenti, E; Guidi, L; Pardossi, A; Tognoni, F

2005-12-28

A series of biochemical parameters, including the concentration of total ascorbic acid (ASA(tot)) and the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidases (PODs), was investigated during cold storage (72 h at 4 degrees C in the dark) in fresh-cut (minimally processed) leaves of two lettuce (Lactuca sativa L. var. acephala) cultivars differing in the susceptibility to tissue browning: Green Salade Bowl (GSB), susceptible, and Red Salade Bowl (RSB), resistant. The two cultivars showed differences also at the biochemical level. The content in ASA(tot) increased in RSB, as a consequence of increased DHA concentration; conversely, ASA(tot) diminished in GSB, in which ASA was not detectable after 72 h of storage, thus suggesting a disappearance of ascorbate (both ASA and DHA) into nonactive forms. The antioxidant capacity (as determined by using FRAP analysis) decreased significantly during storage in RSB, while a strong increase was observed in GSB. PAL activity increased soon after processing reaching a maximum by 3 h, then it declined to a relatively constant value in RSB, while in GSB it showed a tendency to decrease in the first few hours from harvest and processing. POD activity, at least for chlorogenic acid, increased significantly during storage only in GSB.

Toxic effects of copper-based nanoparticles or compounds to lettuce (Lactuca sativa) and alfalfa (Medicago sativa).

Science.gov (United States)

Hong, Jie; Rico, Cyren M; Zhao, Lijuan; Adeleye, Adeyemi S; Keller, Arturo A; Peralta-Videa, Jose R; Gardea-Torresdey, Jorge L

2015-01-01

The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 days-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg L(-1). At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species.

Phytotoxicity of 15 common pharmaceuticals on the germination of Lactuca sativa and photosynthesis of Chlamydomonas reinhardtii.

Science.gov (United States)

Pino, Ma Rosa; Muñiz, Selene; Val, Jonatan; Navarro, Enrique

2016-11-01

Pharmaceuticals reach terrestrial environments through the application of treated wastewaters and biosolids to agricultural soils. We have investigated the toxicity of 15 common pharmaceuticals, classified as nonsteroidal anti-inflammatory drugs (NSAIDs), blood lipid-lowering agents, β-blockers and antibiotics, in two photosynthetic organisms. Twelve pharmaceuticals caused inhibitory effects on the radicle and hypocotyl elongation of Lactuca sativa seeds. The EC 50 values obtained were in the range of 170-5656 mg L -1 in the case of the radicle and 188-4558 mg L -1 for the hypocotyl. Propranolol was the most toxic drug for both root and hypocotyl elongation, followed by the NSAIDs, then gemfibrozil and tetracycline. Other effects, such as root necrosis, inhibition of root growth and curly hairs, were detected. However, even at the highest concentrations tested (3000 mg L -1 ), seed germination was not affected. NSAIDs decreased the photosynthetic yield of Chlamydomonas reinhardtii, but only salicylic acid showed EC 50 values below 1000 mg L -1 . The first effects detected at low concentrations, together with the concentrations found in environmental samples, indicate that the use of biosolids and wastewaters containing pharmaceuticals should be regulated and their compositions assessed in order to prevent medium- and long-term impacts on agricultural soils and crops.

Semi-High Throughput Screening for Potential Drought-tolerance in Lettuce (Lactuca sativa) Germplasm Collections.

Science.gov (United States)

Knepper, Caleb; Mou, Beiquan

2015-04-17

This protocol describes a method by which a large collection of the leafy green vegetable lettuce (Lactuca sativa L.) germplasm was screened for likely drought-tolerance traits. Fresh water availability for agricultural use is a growing concern across the United States as well as many regions of the world. Short-term drought events along with regulatory intervention in the regulation of water availability coupled with the looming threat of long-term climate shifts that may lead to reduced precipitation in many important agricultural regions has increased the need to hasten the development of crops adapted for improved water use efficiency in order to maintain or expand production in the coming years. This protocol is not meant as a step-by-step guide to identifying at either the physiological or molecular level drought-tolerance traits in lettuce, but rather is a method developed and refined through the screening of thousands of different lettuce varieties. The nature of this screen is based in part on the streamlined measurements focusing on only three water-stress indicators: leaf relative water content, wilt, and differential plant growth following drought-stress. The purpose of rapidly screening a large germplasm collection is to narrow the candidate pool to a point in which more intensive physiological, molecular, and genetic methods can be applied to identify specific drought-tolerant traits in either the lab or field. Candidates can also be directly incorporated into breeding programs as a source of drought-tolerance traits.

Development and Characterization of Somatic Hybrids of Ulva reticulata Forsskål (× Monostroma oxyspermum (Kutz.Doty

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Vishal eGupta

2015-01-01

Full Text Available Ulvophycean species with diverse trait characteristics provide an opportunity to create novel allelic recombinant variants. The present study reports the development of seaweed variants with improved agronomic traits through protoplast fusion between Monostroma oxyspermum (Kutz. Doty and Ulva reticulata Forsskål. A total of 12 putative hybrids were screened based on the variations in morphology and total DNA content over the fusion partners. DNA-fingerprinting by inter simple sequence repeat (ISSR and amplified fragment length polymorphism (AFLP analysis confirmed genomic introgression in the hybrids. The DNA fingerprint revealed sharing of parental alleles in regenerated hybrids and a few alleles that were unique to hybrids. The epigenetic variations in hybrids estimated in terms of DNA methylation polymorphism also revealed sharing of methylation loci with both the fusion partners. The functional trait analysis for growth showed a hybrid with heterotic trait (DGR%= 36.7±1.55% over the fusion partners U. reticulata (33.2±2.6% and M. oxyspermum (17.8±1.77%, while others were superior to the mid-parental value (25.2±2.2% (p<0.05. The fatty acid (FA analysis of hybrids showed notable variations over fusion partners. Most hybrids showed increased polyunsaturated FAs (PUFAs compared to saturated FAs (SFAs and mainly includes the nutritionally important linoleic acid, α-linolenic acid, oleic acid, stearidonic acid, and docosahexaenoic acid. The other differences observed include superior cellulose content and antioxidative potential in hybrids over fusion partners. The hybrid varieties with superior traits developed in this study unequivocally demonstrate the significance of protoplast fusion technique in developing improved varients of macroalgae.

Development and Characterization of Somatic Hybrids of Ulva reticulata Forsskål (×) Monostroma oxyspermum (Kutz.)Doty

Science.gov (United States)

Gupta, Vishal; Kumari, Puja; Reddy, CRK

2015-01-01

Ulvophycean species with diverse trait characteristics provide an opportunity to create novel allelic recombinant variants. The present study reports the development of seaweed variants with improved agronomic traits through protoplast fusion between Monostroma oxyspermum (Kutz.) Doty and Ulva reticulata Forsskål. A total of 12 putative hybrids were screened based on the variations in morphology and total DNA content over the fusion partners. DNA-fingerprinting by inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) analysis confirmed genomic introgression in the hybrids. The DNA fingerprint revealed sharing of parental alleles in regenerated hybrids and a few alleles that were unique to hybrids. The epigenetic variations in hybrids estimated in terms of DNA methylation polymorphism also revealed sharing of methylation loci with both the fusion partners. The functional trait analysis for growth showed a hybrid with heterotic trait (DGR% = 36.7 ± 1.55%) over the fusion partners U. reticulata (33.2 ± 2.6%) and M. oxyspermum (17.8 ± 1.77%), while others were superior to the mid-parental value (25.2 ± 2.2%) (p < 0.05). The fatty acid (FA) analysis of hybrids showed notable variations over fusion partners. Most hybrids showed increased polyunsaturated FAs (PUFAs) compared to saturated FAs (SFAs) and mainly includes the nutritionally important linoleic acid, α-linolenic acid, oleic acid, stearidonic acid, and docosahexaenoic acid. The other differences observed include superior cellulose content and antioxidative potential in hybrids over fusion partners. The hybrid varieties with superior traits developed in this study unequivocally demonstrate the significance of protoplast fusion technique in developing improved varients of macroalgae. PMID:25688248

Evaluation of antibacterial properties on polysulfone composite membranes using synthesized biogenic silver nanoparticles with Ulva compressa (L.) Kütz. and Cladophora glomerata (L.) Kütz. extracts.

Science.gov (United States)

Minhas, Fozia T; Arslan, Gulsin; Gubbuk, I Hilal; Akkoz, Cengiz; Ozturk, Betul Yılmaz; Asıkkutlu, Baran; Arslan, Ugur; Ersoz, Mustafa

2018-02-01

Polysulfone (PS) composite membrane using green synthesized biogenic silver nanoparticles (Ag-NPs) with Ulva compressa (L.) Kütz. and Cladophora glomerata (L.) Kütz. extract were prepared by spin coating technique and are tested for antimicrobial activity using a direct contact test for the first time. Initially green synthesis of Ag-NPs was accomplished utilizing green macro algae i.e. U. compressa (L.) Kütz. and C. glomerata (L.) Kütz. by the reduction of AgNO 3 . The Ag-NPs/PS composite membranes from both algae revealed outstanding antimicrobial activity against all bacteria i.e. K. pneumonia, P. aeruginasa, E. coli, E. faecium and S. aureus. Bacterial growth was monitored for 17h with a temperature controlled microplate spectrophotometer. The kinetics of the outgrowth in each well were recorded continuously at 630nm every 60min. Thus present work remarkably offers a feasible, cheap and efficient alternative for making Ag-NPs and their utilization as antimicrobial agent on the PS composite membrane. Copyright © 2017 Elsevier B.V. All rights reserved.

Efficacy of SYBR 14/propidium iodide viability stain for the amphibian chytrid fungus Batrachochytrium dendrobatidis.

Science.gov (United States)

Stockwell, M P; Clulow, J; Mahony, M J

2010-01-25

The amphibian chytrid fungus Batrachochytrium dendrobatidis is a recently described pathogen that has been implicated as a causal agent in the global decline in amphibians. Research into its biology and epidemiology has frequently involved in vitro experimentation. However, this research is currently limited by the inability to differentiate between viable and inviable zoospores. Stains are frequently used to determine cell viability, and this study tested a 2-colour fluorescence assay for the detection and quantification of viable B. dendrobatidis zoospores. The results show that the nucleic acid stains SYBR 14 and propidium iodide are effective in distinguishing live from dead zoospores, and a protocol has been optimized for their use. This viability assay provides an efficient and reliable tool that will have applications in B. dendrobatidis challenge and amphibian exposure experiments.

Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.

Directory of Open Access Journals (Sweden)

Xiao-Xiao Qin

2018-04-01

Full Text Available The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce (Lactuca sativa L. cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole–Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

Beneficial Phytochemicals with Anti-Tumor Potential Revealed through Metabolic Profiling of New Red Pigmented Lettuces (Lactuca sativa L.).

Science.gov (United States)

Qin, Xiao-Xiao; Zhang, Ming-Yue; Han, Ying-Yan; Hao, Jing-Hong; Liu, Chao-Jie; Fan, Shuang-Xi

2018-04-11

The present study aimed to compare polyphenols among red lettuce cultivars and identify suitable cultivars for the development and utilization of healthy vegetables. Polyphenols, mineral elements, and antioxidant activity were analyzed in the leaves of six red pigmented lettuce ( Lactuca sativa L.) cultivars; thereafter, we assessed the anti-tumor effects of cultivar B-2, which displayed the highest antioxidant activity. Quadrupole-Orbitrap mass spectrometry analysis revealed four classes of polyphenols in these cultivars. The composition and contents of these metabolites varied significantly among cultivars and primarily depended on leaf color. The B-2 cultivar had the highest antioxidant potential than others because it contained the highest levels of polyphenols, especially anthocyanin, flavone, and phenolic acid; furthermore, this cultivar displayed anti-tumor effects against the human lung adenocarcinoma cell line A549, human hepatoma cell line Bel7402, human cancer colorectal adenoma cell line HCT-8, and HT-29 human colon cancer cell line. Hence, the new red-leaf lettuce cultivar B-2 has a distinct metabolite profile, with high potential for development and utilization of natural phytochemical and mineral resources in lettuces and can be used as a nutrient-dense food product.

Production and characterization of enzymatic cocktail produced by Aspergillus niger using green macroalgae as nitrogen source and its application in the pre-treatment for biogas production from Ulva rigida.

Science.gov (United States)

Karray, Raida; Hamza, Manel; Sayadi, Sami

2016-09-01

Marine macroalgae are gaining more and more importance as a renewable feedstock for durable bioenergy production, but polysaccharides of this macroalgae are structurally complex in its chemical composition. The use of enzymatic hydrolysis may provide new pathways in the conversion of complex polysaccharides to fermentable sugars. In this study, an enzymatic cocktail with high specificity was first isolated from Aspergillus niger using the green macroalgae Ulva rigida as nitrogen source. The cocktail is rich on β-glucosidase, pectinase and carboxy-methyl-cellulase (CMCase). The highest activity was obtained with β-glucosidase (109IUmL(-1)) and pectinase (76IUmL(-1)), while CMCase present the lowest activity 4.6IUmL(-1). The U. rigida pre-treatment with this enzymatic cocktail showed high rate of reduced sugar release, and could bring promising prospects for enzymatic pre-treatment of the biogas production from U. rigida biomass which reached 1175mLgCODint(-1). Copyright © 2016 Elsevier Ltd. All rights reserved.

Accumulation of aqueous and dietary thallium by the marine snail, Littorina littorea

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Turner, Andrew; Pilsbury, Amy

2013-09-01

Thallium is a highly toxic metal whose biogeochemical behaviour in the marine environment is poorly understood. The dominant species predicted in sea water (Tl+) is also chemically and biologically analogous to the potassium ion. In this study, the accumulation of Tl(I) by the littorinid snail, Littorina littorea, was examined under carefully controlled laboratory conditions for a period of five days. The snail was exposed to sea water amended with a sub-phytotoxic concentration of Tl (5 μg L-1) and to a food source (the green macroalga, Ulva lactuca) that had been pre-contaminated by Tl in sea water at the same concentration. L. littorina accumulated Tl from sea water relative to food in a ratio of about 20:1 and there were no significant differences in Tl concentrations among the different tissues analysed (head, foot, visceral mass, gonads) for each treatment. When availabilities of Tl in each vector were compared, however, it was found that only 2% of sea water Tl was accumulated compared with about 15% of dietary Tl. Uptake of Tl appears to proceed via both the gills and gut, while at the cellular level accumulation likely involves binding with biomolecules and exchange with K+ in potassium-bearing mineralised granules.

Characterization of protein, lipid and mineral contents in common Norwegian seaweeds and evaluation of their potential as food and feed.

Science.gov (United States)

Maehre, Hanne K; Malde, Marian K; Eilertsen, Karl-Erik; Elvevoll, Edel O

2014-12-01

The objectives of this study were to examine protein and amino acid composition, lipid and fatty acid composition, along with a range of essential minerals in common Norwegian seaweed species representing the red (Palmaria palmata and Vertebrata lanosa), green (Cladophora rupestris, Enteromorpha intestinalis and Ulva lactuca) and brown (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Fucus vesiculosus and Pelvetia canaliculata) classes and assess their potential as alternatives to cereals in food and feed. As macroalgae accumulate heavy metals, arsenic, cadmium and mercury were also analyzed. Proteins ranged from 34 to 123 g kg(-1) dry weight (DW) and the essential amino acid levels may cover both human and salmonid requirements. Lipids were low (6-58 g kg(-1) DW), but the red algae had high relative content of long-chained omega-3 fatty acids (32-34 % of the fatty acids). Iodine contents were particularly high in the Laminaria species. Of the heavy metals only arsenic levels may be of concern. In total, the red alga P. palmata was regarded as the best alternative to cereals in food and feed. For several of the other species, single-component extraction for the ingredients market may be better than using the whole product. © 2014 Society of Chemical Industry.

Mosquito larvicidal activity of seaweeds extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus

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Mohamed Yacoob Syed Ali

2013-06-01

Full Text Available Objective: To identify the larvicidal activity of the seaweed extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus Methods: Seaweed extracts of Ulva lactuca, Caulerpa racemosa (C. racemosa, Sargassum microystum, Caulerpa scalpelliformis, Gracilaria corticata, Turbinaria decurrens, Turbinaria conoides and Caulerpa toxifolia were dissolved in DMSO to prepare a graded series of concentration. The test for the larvicidal effect of seaweeds against mosquitos larvae was conducted in accordance with the WHO standard method. Batches of 25 early 4th instar larvae of three mosquitoes were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (10-100 µg. Each experiment was conducted with triplicate with concurrent a control group. Results: Among the seaweeds extract, C. racemosa showed toxicity against 4th instar larvae of Aedes aegypti, Culex quinquefasciatus, Anopheles stephensi with equivalent LC 50 value (0.055 6依0.010 3 µg/mL, (0.067 5依0.136 0 µg/mL and (0.066 1 依0.007 6 µg/mL, respectively. Conclusions: The present study concluded that, the mosquito larvicidal property of C. racemosa might be the prospective alternative source to control the mosquitoes.

Inhibition de Phytophthora palmivora, agent de pourriture brune des ...

African Journals Online (AJOL)

clonage de la souche par isolement mono zoospores a été effectué selon la technique décrite par Babacauh (1980). 2.2.2. Préparation d'inoculum de P. palmivora et Trichoderma sp. L'inoculum de P. palmivora est constitué d'une suspension de zoospores. Elle est obtenue à partir d'une culture âgée de 5 à 6 jours dans.

Nature of vegetative cycle in Phytophthora parasitica Dastur and palmivora (BUTLER) BUTLER

International Nuclear Information System (INIS)

Le Grand-Pernot, Francoise; Pellegrin, F.

1976-01-01

Up to now, neither cytological nor genetical studies have clearly demonstrated the 'ploidy' degree of somatic nuclei in different species of Phytophthora. Two complementary studies, using biological effect of γ rays upon zoospores, and microspectrophotometric techniques measuring relative amount of DNA by nucleus in zoospores or in hyphae, allowed to demonstrate diploid nature of the vegetative phase in P. palmivora (BUTLER) BUTLER and P. parasitica DASTUR cycles [fr

Very Green Photosynthesis of Gold Nanoparticles by a Living Aquatic Plant: Photoreduction of AuIII by the Seaweed Ulva armoricana.

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Mukhoro, Ofhani C; Roos, Wiets D; Jaffer, Mohammed; Bolton, John J; Stillman, Martin J; Beukes, Denzil R; Antunes, Edith

2018-02-01

Light-assisted in vivo synthesis of gold nanoparticles (NPs) from aqueous solutions of dilute Au III salts by a living green marine seaweed (Ulva armoricana) is reported for the first time. NPs synthesised using typical procedures have many associated environmental hazards. The reported methods involve green, nontoxic, eco-friendly synthetic procedures. The formation of AuNPs was extremely rapid (≈15 min) following illumination of the living U. armoricana, while the rate of NP formation in the dark was very slow (over 2 weeks). The properties of the AuNPs formed were confirmed using a battery of spectroscopic techniques. U. armoricana were found to be very efficient in Au 0 uptake, and this, together with the rapid formation of AuNPs under illumination, indicated that the seaweed remained living during NP formation. The TEM images supported this, revealing that the thylakoid membranes and cell structure remained intact. The AuNPs formed on the surface of U. armoricana thallus, along the cell walls and in the chloroplasts. Without further workup, the dried, U. armoricana-supported AuNPs were efficient in the catalytic reduction of 4-nitrophenol, demonstrating the completely green cycle of AuNP formation and catalytic activity. The results mean that an aquatic plant growing in water rich in gold salts could bio-accumulate AuNPs from its aquatic environment, simply with the activation of sunlight. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluation of the phytotoxicity of polycontaminated industrial effluents using the lettuce plant (Lactuca sativa) as a bioindicator.

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Charles, Jérémie; Sancey, Bertrand; Morin-Crini, Nadia; Badot, Pierre-Marie; Degiorgi, François; Trunfio, Giuseppe; Crini, Grégorio

2011-10-01

Industrial wastewater containing heavy metals is generally decontaminated by physicochemical treatment consisting in insolublizing the contaminants and separating the two phases, water and sludge, by a physical process (filtration, settling or flotation). However, chemical precipitation does not usually remove the whole pollution load and the effluent discharged into the environment can be toxic even if it comes up to regulatory standards. To assess the impact of industrial effluent from 4 different surface treatment companies, we performed standardized bioassays using seeds of the lettuce Lactuca sativa. We measured the rate of germination, and the length and mass of the lettuce plantlet. The results were used to compare the overall toxicity of the different effluents: effluents containing copper and nickel had a much higher impact than those containing zinc or aluminum. In addition, germination tests conducted using synthetic solutions confirmed that mixtures of metals have higher toxicity than the sum of their separate constituents. These biological tests are cheap, easy to implement, reproducible and highlight the effects caused by effluent treated with the methods commonly applied in industry today. They could be routinely used to check the impact of industrial discharges, even when they meet regulatory requirements for the individual metals. Copyright © 2011 Elsevier Inc. All rights reserved.

Antimicrobial and antioxidant activities of Cystoseira crinita Duby and Ulva intestinalis Linnaeus from the coastal region of Sinop, Turkey

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İsmet Berber

2015-06-01

Full Text Available Objective: To evaluate in vitro antimicrobial, antioxidant activities and total phenol contents of Cystoseira crinita and Ulva intestinalis species collected from the coastal region of Sinop. Methods: The antimicrobial activity of each methanolic algae sample was screened by using disc diffusion method against to 15 bacteria and 3 yeasts. The antioxidant potential of the extracts on the stable radical 1,1-diphenyl-2-picrylhydrazyl was determined. The total phenolic content of the 3 methanolic extracts of the seaweed samples were determined by the FolinCiocalteu method. Results: The results of antimicrobial assay showed that extracts were more effective against Gram-positive bacteria rather than Gram-negative. In addition, while the algal extracts had antifungal efficacy against Candida krusei, the other yeast strains were not affected at all. According to the findings of antioxidant activity, all methanolic extracts displayed good free radical scavenging activity ranging from IC50 = (32.19 ± 0.08 mg/mL to the IC50 = (37.57 ± 0.11 mg/mL. The total phenols content of the macroalgal extracts were found as between (5.10 ± 0.16 mg gallic acid equivalent/g and (87.70 ± 1.03 mg gallic acid equivalent/g. In this sense, our findings confirmed that there was a positive linear correlations (r = 0.86 between total phenol contents and the IC50 values. Conclusions: The data gathered from this study suggested that the seaweeds can be used as a potential natural seafood sources owing to the antimicrobial efficiency and good antioxidant activity.

Cytotoxic and genotoxic effects of Solanum lycocarpum St.-Hil (Solanaceae on the cell cycle of Lactuca sativa and Allium cepa

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Raquel Bezerra Chiavegatto

2017-06-01

Full Text Available Solanum lycocarpum St.-Hil popularly known as ‘fruta-de-lobo’ or ‘lobeira’ is native to the Brazilian Cerrado, and used in folk medicine due to its phytotherapic properties. The action of S. lycocarpum on the cell cycle and chromosomes in order to demonstrate whether there are aneugenic and/or clastogenic effects is unknown. Thus, this study aimed at investigating the cytotoxic and genotoxic potential of methanol and hexane extracts of S. lycocarpum on growth and cell cycle of Lactuca sativa and Allium cepa. Roots from both species were exposed for 72 hours to methanol and hexane extracts with 50, 100, and 200 µg mL-1 of S. lycocarpum. Slides were prepared by the squash technique and then analyzed to determine the mitotic index and the total of chromosomal and nuclear abnormalities. The frequencies of chromosomal and nuclear abnormalities were high and significant with a dose-dependent effect, indicating that S. lycocarpum has a cytotoxic and genotoxic action depending on the dose used on meristem cells of A. cepa and L. sativa.

Molecular characterization of a divergent strain of calla lily chlorotic spot virus infecting celtuce (Lactuca sativa var. augustana) in China.

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Wu, Xiaodong; Wu, Xiaoyun; Li, Wenbin; Cheng, Xiaofei

2018-05-01

Through sequencing and assembly of small RNAs, an orthotospovirus was identified from a celtuce plant (Lactuca sativa var. augustana) showing vein clearing and chlorotic spots in the Zhejiang province of China. The S, M, and L RNAs of this orthotospovirus were determined to be 3146, 4734, and 8934 nt, respectively, and shared 30.4-72.5%, 43.4-80.8%, and 29.84-82.9% nucleotide sequence identities with that of known orthotospoviruses. The full length nucleoprotein (N) of this orthotospovirus shared highest amino acid sequence identity (90.25%) with that of calla lily chlorotic spot virus isolated from calla lily (CCSV-calla) [China: Taiwan: 2001] and tobacco (CCSV-LJ1) [China: Lijiang: 2014]. Phylogenetic analyses showed that this orthotospovirus is phylogenetically associated with CCSV isolates and clustered with CCSV, tomato zonate spot virus (TZSV), and tomato necrotic spot-associated virus (TNSaV) in a separate sub-branch. These results suggest that this orthotospovirus is a divergent isolate of CCSV and was thus named CCSV-Cel [China: Zhejiang: 2017].

Combination of minimal processing and irradiation to improve the microbiological safety of lettuce (Lactuca sativa, L.)

International Nuclear Information System (INIS)

Goularte, L.; Martins, C.G.; Morales-Aizpurua, I.C.; Destro, M.T.; Franco, B.D.G.M.; Vizeu, D.M.; Hutzler, B.W.; Landgraf, M.

2004-01-01

The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce (Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D 10 -values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage

Combination of minimal processing and irradiation to improve the microbiological safety of lettuce (Lactuca sativa, L.)

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Goularte, L.; Martins, C.G.; Morales-Aizpurua, I.C.; Destro, M.T.; Franco, B.D.G.M.; Vizeu, D.M.; Hutzler, B.W.; Landgraf, M. E-mail: landgraf@usp.br

2004-10-01

The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce (Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D{sub 10}-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

Combination of minimal processing and irradiation to improve the microbiological safety of lettuce ( Lactuca sativa, L.)

Science.gov (United States)

Goularte, L.; Martins, C. G.; Morales-Aizpurúa, I. C.; Destro, M. T.; Franco, B. D. G. M.; Vizeu, D. M.; Hutzler, B. W.; Landgraf, M.

2004-09-01

The feasibility of gamma radiation in combination with minimal processing (MP) to reduce the number of Salmonella spp. and Escherichia coli O157:H7 in iceberg lettuce ( Lactuca sativa, L.) (shredded) was studied in order to increase the safety of the product. The reduction of the microbial population during the processing, the D10-values for Salmonella spp. and E. coli O157:H7 inoculated on shredded iceberg lettuce as well as the sensory evaluation of the irradiated product were evaluated. The immersion in chlorine (200 ppm) reduced coliform and aerobic mesophilic microorganisms by 0.9 and 2.7 log, respectively. D-values varied from 0.16 to 0.23 kGy for Salmonella spp. and from 0.11 to 0.12 kGy for E. coli O157:H7. Minimally processed iceberg lettuce exposed to 0.9 kGy does not show any change in sensory attributes. However, the texture of the vegetable was affected during the exposition to 1.1 kGy. The exposition of MP iceberg lettuce to 0.7 kGy reduced the population of Salmonella spp. by 4.0 log and E. coli by 6.8 log without impairing the sensory attributes. The combination of minimal process and gamma radiation to improve the safety of iceberg lettuce is feasible if good hygiene practices begins at farm stage.

Zn-biofortification enhanced nitrogen metabolism and photorespiration process in green leafy vegetable Lactuca sativa L.

Science.gov (United States)

Barrameda-Medina, Yurena; Lentini, Marco; Esposito, Sergio; Ruiz, Juan M; Blasco, Begoña

2017-04-01

Excessive rates of nitrogen (N) fertilizers may result in elevated concentrations of nitrate (NO 3 - ) in plants. Considering that many programs of biofortification with trace elements are being performed, it has become important to study how the application of these elements affects plant physiology and, particularly, N utilization in leaf crops. The main objective of the present study was to determine whether the NO 3 - accumulation and the nitrogen use efficiency was affected by the application of different doses of Zn in Lactuca sativa plants. Zn doses in the range 80-100 µmol L -1 produced an increase in Zn concentration provoking a decrease of NO 3 - concentration and increase of the nitrate reductase, glutamine synthetase and aspartate aminotransferase activities, as well as the photorespiration processes. As result, we observed an increase in reduced N, total N concentration and N utilization efficiency. Consequently, at a dose of 80 µmol L -1 of Zn, the amino acid concentration increased significantly. Adequate Zn fertilization is an important critical player in lettuce, especially at a dose of 80 µmol L -1 of Zn, because it could result in an increase in the Zn concentration, a reduction of NO 3 - levels and an increase the concentration of essential amino acids, with all of them having beneficial properties for the human diet. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Inter- and intra-annual patterns of Ulva prolifera green tides in the Yellow Sea during 2007-2009, their origin and relationship to the expansion of coastal seaweed aquaculture in China.

Science.gov (United States)

Keesing, John K; Liu, Dongyan; Fearns, Peter; Garcia, Rodrigo

2011-06-01

The large green-tide events that occurred in the Yellow Sea in 2008 (3489km(2)) and 2009 (4994km(2)) are shown to be novel events preceded only once by a much smaller event in 2007 (82km(2)). The blooms originated in the coastal area of Jiangsu province and spread north-east towards the Shandong Peninsula. The blooms grew at different rates and mesoscale variability in surface winds explained the differences in the spatial and temporal patterns of blooms in 2008 and 2009. The 2009 bloom was tracked to its origin immediately offshore of extensive intertidal flats between Yancheng and Nantong where recent rapid expansion of Porphyra aquaculture has occurred. We review published hypotheses which have been advanced to explain the occurrence of blooms and in light of our findings, we conclude that the accumulation and disposal of waste Ulva prolifera from Porphyra aquaculture rafts is the most likely cause of the blooms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Competitive Interactions in Mixed-Species Biofilms Containing the Marine Bacterium Pseudoalteromonas tunicata

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Rao, Dhana; Webb, Jeremy S.; Kjelleberg, Staffan

2005-01-01

Pseudoalteromonas tunicata is a biofilm-forming marine bacterium that is often found in association with the surface of eukaryotic organisms. It produces a range of extracellular inhibitory compounds, including an antibacterial protein (AlpP) thought to be beneficial for P. tunicata during competition for space and nutrients on surfaces. As part of our studies on the interactions between P. tunicata and the epiphytic bacterial community on the marine plant Ulva lactuca, we investigated the hypothesis that P. tunicata is a superior competitor compared with other bacteria isolated from the plant. A number of U. lactuca bacterial isolates were (i) identified by 16S rRNA gene sequencing, (ii) characterized for the production of or sensitivity to extracellular antibacterial proteins, and (iii) labeled with a fluorescent color tag (either the red fluorescent protein DsRed or green fluorescent protein). We then grew single- and mixed-species bacterial biofilms containing P. tunicata in glass flow cell reactors. In pure culture, all the marine isolates formed biofilms containing microcolony structures within 72 h. However, in mixed-species biofilms, P. tunicata removed the competing strain unless its competitor was relatively insensitive to AlpP (Pseudoalteromonas gracilis) or produced strong inhibitory activity against P. tunicata (Roseobacter gallaeciensis). Moreover, biofilm studies conducted with an AlpP− mutant of P. tunicata indicated that the mutant was less competitive when it was introduced into preestablished biofilms, suggesting that AlpP has a role during competitive biofilm formation. When single-species biofilms were allowed to form microcolonies before the introduction of a competitor, these microcolonies coexisted with P. tunicata for extended periods of time before they were removed. Two marine bacteria (R. gallaeciensis and P. tunicata) were superior competitors in this study. Our data suggest that this dominance can be attributed to the ability of

Lettuce Production Hydroponics (Lactuca Sativa L. for the Promotion of Self-Management in Basic School Bolivariana “Los Naranjos”

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Luis Alfredo Díaz

2017-05-01

Full Text Available The present research aims at the promotion of the Hydroponic Lettuce Cultivation (Lactuca Sativa L. as a self - management alternative in the Bolivarian Basic School “Los Naranjos”, Calderas parish, Bolívar municipality of Barinas state. The nature of the study is framed under the modality of the qualitative paradigm, adopting the method of Participatory Action Research. On the other hand, the research will be conducted in (4 four phases: Phase I. Diagnosis, Phase II. Elaboration of the action plan, Phase III. Implementation of the action plan, Phase IV. Reflection, interpretation and integration of results. Information triangulation was used to analyze the information in order to cross-check information from key informants. For all of the above, this study constitutes a significant contribution to the teaching and learning process as it is the responsibility of the family and teachers as promoters and agents of dissemination of knowledge, accept the responsibility in this process of placing children in contact And girls with new techniques of cultivation, in this case with the hydroponic technique, since its early years, so that this is a pleasurable, pleasant and encouraging experience that accompanies him for the rest of his life.

Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

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S. Fatih Ergin

2016-10-01

Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

Comparison between two genera, species and cultivars in Lactuceae, (3)

International Nuclear Information System (INIS)

Haque, M.Z.; Godward, M.B.E.

1986-01-01

Estimation of DNA amounts (in arbitrary units) in two genera, two species, and three cultivars of one species, permits comparison between them and indicates that the biggest difference is between the two genera, Lactuca and Cichorium; but that the difference between the cultivars of Lactuca sativa is greater than the difference between Lactuca serriola and the mean for Lactuca sativa. Lactuca serriola is a presumed ancestor of Lactuca sativa. The most radiosensitive species, L. serriola, has slightly less DNA and smaller nuclear volume than the next most sensitive, L. sativa cult. Cos. This is discussed. (author)

Effect of salicylhydroxamic acid on endosperm strength and embryo growth of Lactuca sativa L. cv Waldmann's Green seeds

Science.gov (United States)

Brooks, C. A.; Mitchell, C. A.

1988-01-01

Salicylhydroxamic acid (SHAM) stimulated germination of photosensitive lettuce (Lactuca sativa L. cv Waldmann's Green) seeds in darkness. To determine whether SHAM acts on the embryo or the endosperm, we investigated separately effects of SHAM on growth potential of isolated embryos as well as on endosperm strength. Embryo growth potential was quantified by incubating decoated embryos in various concentrations of osmoticum and measuring subsequent radicle elongation. Growth potential of embryos isolated from seeds pretreated with 4 millimolar SHAM was equal to that of untreated controls. Rupture strength of endosperm tissue excised from seeds pretreated with SHAM was 33% less than that of controls in the micropylar region. To determine if the embryo must be in contact with the endosperm of SHAM to weaken the endosperm, some endosperms were incubated with SHAM only after dissection from seeds. Rupture strength of SHAM-treated, isolated endosperms in the micropylar region was 25% less than that of untreated controls. There was no difference in rupture strength in the cotyledonary region of endosperm isolated from seeds treated with SHAM in buffer or buffer alone. SHAM therefore stimulates germination not by enhancing embryo growth potential, but by weakening the micropylar region of the endosperm enclosing the embryo.

Temporal pattern in the bloom-forming macroalgae Chaetomorpha linum and Ulva pertusa in seagrass beds, Swan Lake lagoon, North China

International Nuclear Information System (INIS)

Zhang, Xiaomei; Zhou, Yi; Liu, Peng; Wang, Feng; Liu, Bingjian; Liu, Xujia; Xu, Qiang; Yang, Hongsheng

2014-01-01

Highlights: • We conducted an annual survey of bloom-forming macroalgae in a lagoon. • C. linum biomass reached 1712 ± 780 g DW m −2 at the northern part of the lagoon. • Macroalgae δ 15 N values indicated a land-based source of N enrichment to the blooms. • High nutrient concentrations near the river mouth supported the blooms. • C. linum blooms induced the loss of seagrasses and benthic filter feeders. - Abstract: Seagrasses that are distributed over a large area of the Swan Lake, Weihai, China, support a productive ecosystem. In recent years, however, frequent macroalgal blooms have changed the ecosystem structure and threatened the seagrasses. To understand the bloom-forming macroalgae we conducted a yearly field survey of Swan Lake. Results indicated that the macroalgae Chaetomorpha linum and Ulva pertusa both exhibited a much higher productivity and attained a greater maximum biomass (of 1712 ± 780 g DW m −2 and 1511 ± 555 g DW m −2 , respectively) than was the case for the seagrasses. The mean annual atomic ratios of C/N, C/P and N/P in C. linum were 14.31 ± 4.45, 402.82 ± 130.25, and 28.12 ± 2.08, respectively. The δ 15 N values (11.09 ± 0.91‰ for C. linum; 9.27 ± 2.83‰ for U. pertusa) indicated a land-based source of N enrichment to the macroalgal blooms. High concentrations of nitrogen and phosphorus in the lagoon, particularly near the river mouth, supported the blooms

A strategy for the proliferation of Ulva prolifera, main causative species of green tides, with formation of sporangia by fragmentation.

Science.gov (United States)

Gao, Shan; Chen, Xiaoyuan; Yi, Qianqian; Wang, Guangce; Pan, Guanghua; Lin, Apeng; Peng, Guang

2010-01-05

Ulva prolifera, a common green seaweed, is one of the causative species of green tides that occurred frequently along the shores of Qingdao in 2008 and had detrimental effects on the preparations for the 2008 Beijing Olympic Games sailing competition, since more than 30 percent of the area of the games was invaded. In view of the rapid accumulation of the vast biomass of floating U. prolifera in green tides, we investigated the formation of sporangia in disks of different diameters excised from U. prolifera, changes of the photosynthetic properties of cells during sporangia formation, and development of spores. The results suggested that disks less than 1.00 mm in diameter were optimal for the formation of sporangia, but there was a small amount of spore release in these. The highest percentage of area of spore release occurred in disks that were 2.50 mm in diameter. In contrast, sporangia were formed only at the cut edges of larger disks (3.00 mm, 3.50 mm, and 4.00 mm in diameter). Additionally, the majority of spores liberated from the disks appeared vigorous and developed successfully into new individuals. These results implied that fragments of the appropriate size from the U. prolifera thalli broken by a variety of factors via producing spores gave rise to the rapid proliferation of the seaweed under field conditions, which may be one of the most important factors to the rapid accumulation of the vast biomass of U. prolifera in the green tide that occurred in Qingdao, 2008.

A strategy for the proliferation of Ulva prolifera, main causative species of green tides, with formation of sporangia by fragmentation.

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Shan Gao

Full Text Available Ulva prolifera, a common green seaweed, is one of the causative species of green tides that occurred frequently along the shores of Qingdao in 2008 and had detrimental effects on the preparations for the 2008 Beijing Olympic Games sailing competition, since more than 30 percent of the area of the games was invaded. In view of the rapid accumulation of the vast biomass of floating U. prolifera in green tides, we investigated the formation of sporangia in disks of different diameters excised from U. prolifera, changes of the photosynthetic properties of cells during sporangia formation, and development of spores. The results suggested that disks less than 1.00 mm in diameter were optimal for the formation of sporangia, but there was a small amount of spore release in these. The highest percentage of area of spore release occurred in disks that were 2.50 mm in diameter. In contrast, sporangia were formed only at the cut edges of larger disks (3.00 mm, 3.50 mm, and 4.00 mm in diameter. Additionally, the majority of spores liberated from the disks appeared vigorous and developed successfully into new individuals. These results implied that fragments of the appropriate size from the U. prolifera thalli broken by a variety of factors via producing spores gave rise to the rapid proliferation of the seaweed under field conditions, which may be one of the most important factors to the rapid accumulation of the vast biomass of U. prolifera in the green tide that occurred in Qingdao, 2008.

Studying the effects of different levels of salinity which caused by NaCl on early growth and germination of Lactuca Sativa L. seedling

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Mohammad Hosein Bijeh Keshavarzi

2012-04-01

Full Text Available Soil salinity is one of the most important constraints that limit crop production in arid and semi arid regions. Seed germination is a critical stage in the history of plants and salt tolerance during germination is crucial for the establishment of plants that grow in saline soils. This research was carried out in order to test the effects of different salinity levels on germination and early growth of lettuce (Lactuca Sativa L.. The experiment was carried out using completely randomized design in four replication in 2011 Zabol University laboratory Iran. The results showed that by increasing salinity, percentage and race of germination decreased, So that, in the 150 mM of salinity level, germination reached to minimized (8.33%. Other measured parameters such as plumule length, radicle length, dry and wet weight decreased as well. All the results analyzed by SAS statistical software and comparison of average had done by Duncan test on 5% possible level.

[Enteroparasite determination in Lactuca sativa from farms dedicated to its production in Pasto, Colombia].

Science.gov (United States)

Polo, Giovanni Andrés; Benavides, Carmenza Janneth; Astaiza, Juan Manuel; Vallejo, Dario Antonio; Betancourt, Patricia

2016-12-01

Currently, vegetables like lettuce are widely recommended as part of the daily diet given their high nutritional value; however, while consumers feel attracted to the benefits provided by the vegetable, they may also be exposed to parasitic intestinal infections. To determine the presence or absence of enteroparasites in lettuce (Lactuca sativa) grown in the rural area in the municipality of Pasto, and to analyze associated factors based on the characterization of the lands. We conducted a descriptive double blind cross-sectional study. We took a total of 105 samples from 21 properties from June to December, 2013, and we processed them by sedimentation and flotation tests. Additionally, the owners were surveyed in order to obtain information about the possible variables influencing the occurrence of enteroparasites. We detected contamination in 100% of the lettuce samples and we found parasite eggs and larvae as follows: 95.25% with Entamoeba spp. cysts; 71.43% with Isospora spp. oocysts; 61.90% with Strongyloides stercoralis larvae (L3); 28.57% with Toxocara spp. eggs, and 4.76% with Eimeria spp. oocysts. Using the chi-square test we found association between Entamoeba spp. and ditches (p=0.008), dogs (p=0.008) and septic tanks (p=0.029); between Isospora spp. and compost (p=0.0001), dogs (p=0.0001) and slugs (p=0.002); between S. stercoralis and handling (p=0.003), and between Toxocara spp. and no use of biodigesters (p= 0.002). We found contamination with enteroparasites in lettuce samples from growing areas in the municipality of Pasto with animal and human sources as their main reservoirs, although others were present in the environment.

Evaluation of zinc oxide nanoparticles on lettuce (Lactuca sativa L.) growth and soil bacterial community.

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Xu, Jiangbing; Luo, Xiaosan; Wang, Yanling; Feng, Youzhi

2018-02-01

The wide spread of nanoparticles (NPs) has caused tremendous concerns on agricultural ecosystem. Some metallic NPs, such as zinc oxide (ZnO), can be utilized as a nano-fertilizer when used at optimal doses. However, little is known about the responses of plant development and concomitant soil bacteria community to ZnO NPs. The present pot experiment studied the impacts of different doses of ZnO NPs and bulk ZnO (0, 1, 10, 100 mg ZnO/kg), on the growth of lettuce (Lactuca sativa L.) and the associated rhizospheric soil bacterial community. Results showed that at a dose of 10 mg/kg, ZnO NPs and bulk ZnO, enhanced the lettuce biomass and the net photosynthetic rate; whereas, the Zn content in plant tissue was higher in NPs treatment than in their bulk counterpart at 10 mg/kg dose or higher. For the underground observations, 10 mg/kg treatment doses (NPs or bulk) significantly changed the soil bacterial community structure, despite the non-significant variations in alpha diversity. Taxonomic distribution revealed that some lineages within Cyanobacteria and other phyla individually demonstrated similar or different responses to ZnO NPs and bulk ZnO. Moreover, some lineages associated with plant growth promotion were also influenced to different extents by ZnO NPs and bulk ZnO, suggesting the distinct microbial processes occurring in soil. Collectively, this study expanded our understanding of the influence of ZnO NPs on plant performance and the associated soil microorganisms.

[Calcium distribution in the central cell of lettuce (Lactuca sativa L.) before and after pollination].

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Qiu, Yi Lan; Liu, Ru Shi; Ye, Lv; Tian, Hui

2008-02-01

Potassium antimonite precipitation was used to locate calcium in the central cell of lettuce (Lactuca sativa L.) before and after pollination. At 3d before anthesis, two polar nuclei of central cell separately located at two polarity of the cell, and few calcium precipitates (ppts) appeared in the polar nuclei and cytoplasm, but some ppts in its small vacuoles. At 2d before anthesis, two polar nuclei moved toward the middle of the cell and fused to form a secondary nucleus, and the ppts evidently increased in the nucleus and cytoplasm. At 1d before anthesis, secondary nucleus again moved toward micropylar end and located near the egg to prepare for fertilization. Calcium precipitates were mainly accumulated in the secondary nucleus. After pollination and before fertilization, the distribution of calcium ppts was similar to that before pollination. At 4h after pollination, the central cell was fertilized, and calcium ppts evidently increased in the cell and numerous were accumulated in its nucleus and cytoplasm. At 6h after pollination, the primary endosperm nucleus completed its first division and formed two dissociate endosperm nuclei, and still many calcium precipitates appeared in the nucleus and cytoplasm. With endosperm development, calcium ppts decreased in the endosperm cell. At 1d after emasculated and without pollination, the secondary nucleus of the cell still bordered on the egg and some calcium ppts appeared in the secondary nucleus. The results indicated that the temporal and spatial changes of calcium in the central cell may play an important physiological role during the development of the central cell and endosperm.

Volatiles emitted by Bacillus sp. BCT9 act as growth modulating agents on Lactuca sativa seedlings.

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Fincheira, Paola; Parra, Leonardo; Mutis, Ana; Parada, Maribel; Quiroz, Andrés

2017-10-01

Chemical products are applied during horticulture to increase food production, but the environmental problems resulting from these applications have led to a search for more sustainable products. Volatile organic compounds (VOCs) demonstrating plant growth promoter (PGP) activity released by bacterial species have emerged as alternatives, but their effects on Lactuca sativa growth are unknown. In this study, VOCs released by Bacillus sp. BCT9 cultures grown in different media (Methyl Red & Voges Proskauer, Murashige & Skoog and nutrient media) at concentrations of 0.1, 0.2, 0.5 and 0.7 (measured as the absorbance, λ=600nm) were tested to evaluate their activity as growth inducers of L. sativa after 10days of exposure. Lower concentrations of BCT9 increased root length, and higher concentrations induced shoot length and lateral root length. The dry weight and number of lateral roots increased similarly, independent of concentration, for VOCs produced in all culture media. BCT9 cultures grown in Methyl Red & Voges Proskauer medium as bioactive compounds with or without lanolin. These VOCs increased shoot length, root length and dry weight at low concentrations, independent of the presence of lanolin. Lateral root length increased with the application of 2-nonanone (50ppm) and 2-undecanone (0.05ppm). Based on these results, the use of bioactive volatiles as growth inducers of horticultural species represents an alternative or complementary strategy. Copyright © 2017 Elsevier GmbH. All rights reserved.

Physiological Mechanisms Only Tell Half Story: Multiple Biological Processes are involved in Regulating Freezing Tolerance of Imbibed Lactuca sativa Seeds.

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Jaganathan, Ganesh K; Han, Yingying; Li, Weijie; Song, Danping; Song, Xiaoyan; Shen, Mengqi; Zhou, Qiang; Zhang, Chenxue; Liu, Baolin

2017-03-13

The physiological mechanisms by which imbibed seeds survive freezing temperatures in their natural environment have been categorized as freezing avoidance by supercooling and freezing tolerance by extracellular freeze-desiccation, but the biochemical and molecular mechanisms conferring seed freezing tolerance is unexplored. In this study, using imbibed Lactuca sativa seeds we show that fast cooled seeds (60 °C h -1 ) suffered significantly higher membrane damage at temperature between -20 °C and -10 °C than slow cooled (3 °Ch -1 ) seeds (P  0.05). However, both SOD activity and accumulation of free proline were induced significantly after slow cooling to -20 °C compared with fast cooling. RNA-seq demonstrated that multiple pathways were differentially regulated between slow and fast cooling. Real-time verification of some differentially expressed genes (DEGs) revealed that fast cooling caused mRNA level changes of plant hormone and ubiquitionation pathways at higher sub-zero temperature, whilst slow cooling caused mRNA level change of those pathways at lower sub-zero ttemperatures. Thus, we conclude that imbibed seed tolerate low temperature not only by physiological mechanisms but also by biochemical and molecular changes.

Phytotoxicity of three plant-based biodiesels, unmodified castor oil, and Diesel fuel to alfalfa (Medicago sativa L.), lettuce (Lactuca sativa L.), radish (Raphanus sativus), and wheatgrass (Triticum aestivum).

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Bamgbose, Ifeoluwa; Anderson, Todd A

2015-12-01

The wide use of plant-based oils and their derivatives, in particular biodiesel, have increased extensively over the past decade to help alleviate demand for petroleum products and improve the greenhouse gas emissions profile of the transportation sector. Biodiesel is regarded as a clean burning alternative fuel produced from livestock feeds and various vegetable oils. Although in theory these animal and/or plant derived fuels should have less environmental impact in soil based on their simplified composition relative to Diesel, they pose an environmental risk like Diesel at high concentrations when disposed. The aim of the present study was to ascertain the phytotoxicity of three different plant-derived biodiesels relative to conventional Diesel. For phytotoxicological analysis, we used seeds of four crop plants, Medicago sativa, Lactuca sativa, Raphanus sativus, and Triticum aestivum to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with two different soil textures: sandy loam soil and silt loam soil. The studied plant-based biodiesels were safflower methyl-ester, castor methyl ester, and castor ethyl-ester. Biodiesel toxicity was more evident at high concentrations, affecting the germination and survival of small-seeded plants to a greater extent. Tolerance of plants to the biodiesels varied between plant species and soil textures. With the exception of R. sativus, all plant species were affected and exhibited some sensitivity to the fuels, such as delayed seedling emergence and slow germination (average=10 days) at high soil concentrations (0.85% for Diesel and 1.76% for the biodiesels). Tolerance of plants to soil contamination had a species-specific nature, and on average, decreased in the following order: Raphanus sativus (0-20%)>Triticum aestivum (10-40%) ≥ Medicago sativa> Lactuca sativa (80-100%). Thus, we conclude that there is some phytotoxicity associated with plant-based biodiesels. Further

Trophic linkage of a temperate intertidal macrobenthic food web under opportunistic macroalgal blooms: A stable isotope approach

International Nuclear Information System (INIS)

Park, Hyun Je; Han, Eunah; Lee, Young-Jae; Kang, Chang-Keun

2016-01-01

The effects of blooms of opportunistic green macroalgae, Ulva prolifera, on the trophic structure of the macrobenthic food web in a temperate intertidal zone on the western coast of Korea were evaluated using carbon and nitrogen stable isotopes. Biomasses of Ulva and microphytobenthos (MPB) increased significantly at the macroalgae-bloom and the non-bloom sites, respectively, from March to September 2011. The δ 13 C values of most the consumers were arrayed between those of MPB and Ulva at both sites, and differed according to feeding strategies at the macroalgae-bloom site. Seasonally increasing magnitudes in δ 13 C and δ 15 N values of consumers were much steeper at the macroalgae-bloom site than at the non-bloom site. Our findings provide evidence that blooming green macroalgae play a significant role as a basal resource supporting the intertidal macrobenthic food web and their significance varies with feeding strategies of consumers as well as the resource availability. - Highlights: • Trophic effects of Ulva blooms on intertidal macrobenthic food web were evaluated. • Biomasses of Ulva increased at the macroalgae-bloom from March to September. • δ 13 C and δ 15 N values of consumers differed with feeding strategy and season. • Trophic significance of blooming macroalgae varies with feeding strategies of consumers. • Ulva blooms play a significant role as a basal resource supporting the intertidal food web.

Zoosporogênese in vitro entre isolados do oomiceto Pythium insidiosum In vitro zoosporogenesis among oomycetes Pythium insidiosum isolates

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Daniela Isabel Brayer Pereira

2008-02-01

Full Text Available Pythium insidiosum é um oomiceto aquático, responsável pela etiologia da pitiose, uma enfermidade crônica, observada freqüentemente em eqüinos. A produção de zoósporos móveis por este microrganismo se constitui no fator determinante da ocorrência da enfermidade. Este estudo avaliou a zoosporogênese e quantificou a produção de zoósporos de 32 amostras de Pythium insidiosum isoladas de eqüinos naturalmente infectados. Pythium insidiosum foi cultivado em meio Corn Meal Agar acrescido de fragmentos de grama, durante 5 dias, a 37°C. Posteriormente, os fragmentos de grama parasitados foram incubados em Meio de Indução a 37°C, por 24 horas. Observou-se que 16 amostras (50% produziram 20.000 zoósporos mL-1, 12 isolados (37,5% produziram acima de 20.000 zoósporos mL-1, enquanto quatro amostras (12,5% produziram menos de 20.000 zoósporos mL-1. O período de maior produção de zoósporos foi entre 6 e 8 horas de incubação. O protocolo utilizado na indução da zoosporogênese mostrou-se eficiente e representa uma importante ferramenta, tanto para a identificação do Pythium insidiosum, como para a obtenção de zoósporos em quantidades suficientes para a inoculação em animais experimentais e aplicação no desenvolvimento de testes de suscetibilidade.Pythium insidiosum is an aquatic oomycete and the etiology of a chronic disease called pythiosis, commonly found in the skin of horses. The production of mobile zoospores by this microorganism is the determinant factor of this disease. This study evaluated the zoosporogenesis and quantification of zoospores in 32 samples of Pythium insidiosum isolated from horses with pythiosis. The assay used culture of the Pythium insidiosum in Corn Meal Agar plus grass blades for 5 days at 37°C. The grass blades were incubated in Induction Medium at 37°C for 24 hours. The findings showed 16 samples (50% yielded 20,000 zoospores mL-1, 12 (37.5% samples yielded over 20,000 zoospores mL-1 and 4

RESPON DUA VARIETAS TANAMAN SELADA (Lactuca sativa L. TERHADAP MACAM NUTRISI PADA SISTEM HIDROPONIK

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Catur Wasonowati

2013-03-01

Full Text Available Lettuce (Lactuca sativa L is a common vegetables crops grown in the highland and lowlands.  A sample hydroponic lettuce cultivation provides an sources an alternative for farmers who have a narrow area, so that can server as an adequate source of income.  Providing nutrients to the two varienties of lettuce are expected to yield maximum production.  This tudy aims to determine the effect of nutrients on two varieties of lettuce plants.            The study was conducted in the greenhouse Agroekoteknologi Departement Faculty of Agriculture, University Trunojoyo Madurese from January to March 2011.  The method used was a factorial experiment based on Completely Randomized Design (CRD with three replicates consisting of two treatment factors, the first factor are two different varieties of lecctuce and the second factor are two differwnt kinds of nutrients.            The results showed that the chief varieties of butter (V1 produces the number of leaves and dry biomass is higher than the varieties of cos (V2.  Nutrition in V1 generate the number of leaves, wet biomass, dry biomass, and root length was higher than without the provision of (N0. V1 responses to nutrient hidrogroup (N1 resulted in higher leaf number than nutrition greentonik (N2, but the provision of dry biomass yield N2 higher than N1. Nutrition on V2 generate the number of leaves, wet biomass and dry biomass was higher than N0. V2 response to the provision of N1 and N2 produce the number of leaves, wet biomass, dry biomass, and root length are not significantly different.Key word : lettuce, varieties, nutrition, simple hydroponics

Lactuca spp. seeds as a bioindicator for the toxicity of Gezira Tannery Corporation wastewater.

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Abdalla, Ammar M S; Bashir, Nabil H H; Assad, Yousif O H

2013-02-01

This study was conducted to establish the potential of lettuce (Lactuca sativa L. var. buttercrunch) seeds as a bioindicator (BI), or a biological tool for detecting the presence of some toxic materials used in tanning industry and determining their concentrations using the germination percentage as a parameter (indicator). Samples of Gezira Tannery Corporation (GTC) wastewater (WW) were collected from both the mouth and the tail of the drainage stream. Lettuce seeds (10/Petri dish, replicated 3x and each experiment was repeated 3x) were treated by GTC WW and other important tanning agents (chromium oxide, sodium sulfide, Preventol WB) in solution using different concentrations of each and their mixture. The bioassay experiment revealed that the seeds were intoxicated (i.e. reduced the germination percentage), when exposed to the WW. On exposure to several concentrations from each input, the concentrations that can be measured by this BI (i.e. sensitivity and reliability) are: chromium oxide from 0.1 to 3.25%, sodium sulfide from 0.19 to 1.5% and Preventol WB from 18.75 to 150 ppm. Lower concentrations cannot be measured, and higher concentrations resulted in 100% inhibition. The IC50 was determined by probit analysis for the WW, mixture of the three inputs, chromium oxide alone, sodium sulfide alone and Preventol WB alone were: 35.5, 14.5, 0.44, 0.45 and 0.005%, respectively. The slopes of the log-dose probability lines (Ld-P) showed that this BI response to all treatments was homogeneous (> 2) (tabulated X2 (df = n - 2) at 5% = 0.172, 0.11, 0.064, 0.05 and 0.05). It is concluded that lettuce seeds satisfy almost all the required properties of the ideal BI.

Multi-resource data-based research on remote sensing monitoring over the green tide in the Yellow Sea

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Gao, Zhiqiang; Xu, Fuxiang; Song, Debin; Zheng, Xiangyu; Chen, Maosi

2017-09-01

This paper conducted dynamic monitoring over the green tide (large green alga—Ulva prolifera) occurred in the Yellow Sea in 2014 to 2016 by the use of multi-source remote sensing data, including GF-1 WFV, HJ-1A/1B CCD, CBERS-04 WFI, Landsat-7 ETM+ and Landsta-8 OLI, and by the combination of VB-FAH (index of Virtual-Baseline Floating macroAlgae Height) with manual assisted interpretation based on remote sensing and geographic information system technologies. The result shows that unmanned aerial vehicle (UAV) and shipborne platform could accurately monitor the distribution of Ulva prolifera in small spaces, and therefore provide validation data for the result of remote sensing monitoring over Ulva prolifera. The result of this research can provide effective information support for the prevention and control of Ulva prolifera.

Effect of soil cadmium on growth, photosynthesis and quality of Raphanus sativus and Lactuca sativa.

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Kaur, Navjyot; Jhanji, Shalini

2016-09-01

Cadmium (Cd) raises serious concerns as its accumulation in the plant not only affect the growth and quality of plant but also threaten the health of consumers. In this research, two vegetables, i.e., radish (Raphanus sativus L.) and lettuce (Lactuca sativa L), were planted in pots having soil treated with Cd as Cd (NO3)2 at different doses (25, 50, 100 and 200 mg Cd kg-1 soil ) to investigate the influence of cadmium on their growth, photosynthetic attributes and quality. Cadmium retarded plant growth as dry weight of radish roots decline by 87% and leaves by 83% following 200 mg Cd kg-1 soil application and the corresponding values for lettuce were 64 and 69% respectively. Significant reductions in various photosynthetic parameters viz., leaf area per plant, total chlorophyll, Chl a and Chl b content were also recorded with Cd applications. The Cd treatments resulted in loss of membrane integrity as revealed by significant increase in electrolyte leakage in leaves of both vegetables. There was significant increase in Cd accumulation in radish and lettuce with all applications but no visual symptoms of Cd toxicity were noticed with 25 and 50 mg Cd kg-1 soil application except for yield differences, illustrating that Cd accumulate in this crop without visual evidence of its presence. However, toxicity symptoms in the form of interveinal chlorosis of the leaf lamina, followed by necrosis and leaf rolling, were clearly evident with 100 and 200 mg Cd kg-1 soil application. Apparently, Cd causes harm due to its phytotoxic effects and high accumulation in edible parts of radish and lettuce without any visible symptoms that constitutes a substantial hazard to human health.

Effect of quorum sensing signals produced by seaweed-associated bacteria on carpospore liberation from Gracilaria dura

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Ravindra Pal Singh

2015-03-01

Full Text Available Epiphytic and endophytic bacteria associated with green macroalgae Ulva (U. fasciata and U. lactuca and red macroalgae Gracilaria (G. corticata and G. dura have been identified from three different seasons to evaluate the effect of quorum sensing molecules on carpospores liberation from Gracilaria dura. The bacterial isolates belonging to the orders Bacillales, Pseudomonadales, Alteromonadales and Vibrionales were present in all seasons, whereas Actinomycetales and Enterobacteriales were confined to pre-monsoon and post-monsoon seasons, respectively. Among all the Gram-negative bacteria, seven isolates were found to produce different types of N-acyl homoserine lactones (AHLs. Interestingly, Shewanella algae produced five types of AHL: C4-HSL, HC4-HSL, C6-HSL, 3-oxo-C6-HSL and 3-oxo-C12-HSL. Subsequently, the AHLs producing bacterial isolates were screened for carpospore liberation from G. dura and these isolates were found to positively induce carpospore liberation over the control. Also, observed that carpospore liberation increased significantly in C4- and C6-HSL treated cystocarps. Sodium dodecyl sulfate and native polyacrylamide gel electrophoresis of the total protein of the C4- and C6-HSL-treated cystocarps showed two specific peptide bands of different molecular weights (50 kDa and 60 kDa as compared to the control, confirming their indirect effect on carpospore liberation.

Main nutritional contents of 30 Dalian coastal microalgae species

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Su, Xiurong; Liu, Huihui; Chen, Kwan Paul

2004-12-01

This paper reports results of study on the contents of proteins, amino acids, polysaccharose and uronic acids in 30 species of macroalgae from Shicao, Heishijiao, Shimiao, and Xiaofujiazhuang in the vicinity of Dalian City, N.E.China. The results showed that the protein contents of the 30 algae from highest (112.55 μ g/ml) to the lowest (0.24 μg/ml) was in the descending order of Dictyopteris ndalata, Gelidium vagum, Gymnogongrus japonican, Ectocarpus confervoides, Tinocladia crassa, Sargassum thunberii. In general, the protein content in red algae was higher than that in brown algae. The content of free amino acids showed no significent differences from 7.44 μg/ml4.96 μg/ml in all these algae, in the descending order of Gymnogongrus japonican, Sargassum confusum, Undoria pinnatifida, Laminaria japonica and Ectocarpus confervoides. The content of polysaccharose varied from 168.2 μ/ml-22.15 μg/ml in the descending order of Symphocladia latiuscula, Scytosiphon lomentarius, Desmarestia viridis., Tinocladia crassa, Gracilaria asiatica and Porphyra yezoensis. The content of uronic acids is from 196.24μg/ml-20.77 μg/ml in the descending order of Ulva lactuca, Symphyoclaldia latiuscula, Scytosiphon lomentarius, Ceramimum kodoi, Gracilaria vemucosa and Porphyra yezoensis. The fatty acids in 30 species of algae belong to Rhodophyta, Chlorophyta and Phaeophyta. Most phaeophytes have many (4 12) types of fatty acids.

Mercury concentrations in the coastal marine food web along the Senegalese coast.

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Diop, Mamadou; Amara, Rachid

2016-06-01

This paper presents the results of seasonal (wet and dry seasons) and spatial (five sites) variation of mercury concentration in seven marine organisms representative for shallow Senegalese coastal waters and including species of commercial importance. Total mercury levels were recorded in the green algae (Ulva lactuca); the brown mussel (Perna perna); the Caramote prawn (Penaeus kerathurus); and in the liver and muscles of the following fish: Solea senegalensis, Mugil cephalus, Saratherondon melanotheron, and Sardinella aurita. The total selenium (Se) contents were determined only in the edible part of Perna perna, Penaeus kerathurus and in the muscles of Sardinella aurita and Solea senegalensis. Hg concentration in fish species was higher in liver compared to the muscle. Between species differences in Hg, concentrations were recorded with the highest concentration found in fish and the lowest in algae. The spatiotemporal study showed that there was no clear seasonal pattern in Hg concentrations in biota, but spatial differences existed with highest concentrations in sites located near important anthropogenic pressure. For shrimp, mussel, and the muscles of sardine and sole, Hg concentrations were below the health safety limits for human consumption as defined by the European Union. The Se/Hg molar ratio was always higher than one whatever the species or location suggesting a protection of Se against Hg potential adverse effect.

Temporal changes of 210Po in temperate coastal waters

International Nuclear Information System (INIS)

Wildgust, M.A.; White, K.N.; McDonald, P.

1998-01-01

The temporal variation of Polonium-210 ( 210 Po) was examined in coastal sea water, the mussel Mytilus edulis, the winkle Littorina littorea and green algae Ulva lactuca in order to investigate the entry of 210 Po into the marine food chain. More than 99% of 210 Po in the water column occurred in the particulate phase. Dissolved 210 Po concentrations peaked during the spring phytoplankton bloom and it is suggested this is related to preferential scavenging of 210 Po by the increased numbers of bacteria, viruses and small dissolved particulates. Changes in L. Littorea 210 Po specific activity are thought not to be related to food, but to a drop in body weight following spawning. Much of the 210 Po accumulated by M. edulis was located in the digestive gland. The specific activity of 210 Po in the digestive gland of M. edulis was shown to be strongly correlated with changes in sea water suspended particulate specific activity. Examination of other trace metal (Ag, Al, As, Ca, Cd, Cr, Co, Cu, Fe, Hg, K, Mg, Mn, Na, Ni Sb, Se, Sn and Zn) variations in the digestive gland revealed that class B and borderline metals had a strong positive correlation with 210 Po. On-going work is investigating whether the accumulation and loss of 210 Po is affected by the presence of metallothioneins

Algal massive growth in relation to water quality and salinity at Damietta, north of Egypt

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Mohamed Ali Ibraheem Deyab

2015-02-01

Full Text Available Objective: To relate the proliferation and dominance of certain algal species at the Damietta and its relation to water quality. Methods: Water and algal biomass were bimonthly sampled from five selected sites at Damietta Province, Egypt during 2012. Algae were identified and quantified. Waters, algae and sediment were analyzed. Results: The physicochemical properties of water showed limited seasonal but substantial local variation. The high levels of nitrogen and phosphorus and turbidity of water pointed to marked eutrophication, which could enhance massive algal growth. The temporal fluctuation in temperature, exposure to industrial and domestic sewage and salinity results in succession between blooming algal species. Spirulina platensis and Chlorella vulgaris alternated in a moderately saline water and Oscillatoria agardhii and Mougeotia scalaris in a fresh water body during summer and winter respectively. Likewise, Microcystis aureginosa and Ulva lactuca alternated in a moderately saline site during autumn and summer respectively. Cladophora albida dominated a fish pond of brackish water and Dunaliella salina dominated the most saline water over the whole period of study. Conclusions: Growth of the predominant algal species is correlated to water quality. These species are of considerable nutritive value, with moderate contents of protein, carbohydrate, macronutrients and micronutrients, which evaluates them for usage as food (green and macroalgae, fodder or bio-fertilizer (cyanophytes.

Benthic macroalgae as biological indicators of heavy metal pollution in the marine environments: a biomonitoring approach for pollution assessment.

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Chakraborty, Sukalyan; Bhattacharya, Tanushree; Singh, Gurmeet; Maity, Jyoti Prakash

2014-02-01

Metal pollution in the marine coastline environment is an important topical issue in the context of ecological disturbance and climate change. Heavy metal contaminations (Cd, Cr, Cu, Mn, Ni, Pb and Zn) in seawater and surficial sediments, as well as macroalgal diversity, were determined in six different locations along the coast of the Gulf of Kutch in India. The marine coastline environment was found to be enriched with Cd and Zn in comparison to other metals. Significant (p ≤ 0.05) inter-elemental positive-correlations were observed between Fe-Mn, Fe-Cu, Fe-Cr, Fe-Zn, Cr-Cu, Cu-Mn, and Cd-Zn, as well as negative-correlations between Cd-Pb, Ni-Pb, and Zn-Pb. Though genus specific macroalgal responses to heavy metal accumulation were significant, species specific response was insignificant (p ≤ 0.05). The relative abundance of metals in macroalgae followed the order of Fe>Zn>Mn>Cu>Cd>Cr>Ni>Pb. The high uptake of metals in green algae (Ulva lactuca and Enteromorpha intestinalis) and brown algae (Padina gymnospora and Dictyota bartayresiana) suggested that these algae may be used as potential biomonitors for heavy metal pollution. Three pollution indicators, Contamination Factor (CF), Enrichment Factor (EF) and Geochemical Index (Igeo) were calculated to determine the degree of metal pollution in the marine coastline and the contribution of anthropogenic influence. © 2013 Published by Elsevier Inc.