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Sample records for batch culture growth

  1. Synchronous protein cycling in batch cultures of the yeast Saccharomyces cerevisiae at log growth phase.

    Science.gov (United States)

    Romagnoli, Gabriele; Cundari, Enrico; Negri, Rodolfo; Crescenzi, Marco; Farina, Lorenzo; Giuliani, Alessandro; Bianchi, Michele M

    2011-12-10

    The assumption that cells are temporally organized systems, i.e. showing relevant dynamics of their state variables such as gene expression or protein and metabolite concentration, while tacitly given for granted at the molecular level, is not explicitly taken into account when interpreting biological experimental data. This conundrum stems from the (undemonstrated) assumption that a cell culture, the actual object of biological experimentation, is a population of billions of independent oscillators (cells) randomly experiencing different phases of their cycles and thus not producing relevant coordinated dynamics at the population level. Moreover the fact of considering reproductive cycle as by far the most important cyclic process in a cell resulted in lower attention given to other rhythmic processes. Here we demonstrate that growing yeast cells show a very repeatable and robust cyclic variation of the concentration of proteins with different cellular functions. We also report experimental evidence that the mechanism governing this basic oscillator and the cellular entrainment is resistant to external chemical constraints. Finally, cell growth is accompanied by cyclic dynamics of medium pH. These cycles are observed in batch cultures, different from the usual continuous cultures in which yeast metabolic cycles are known to occur, and suggest the existence of basic, spontaneous, collective and synchronous behaviors of the cell population as a whole. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. A novel process-based model of microbial growth: self-inhibition in Saccharomyces cerevisiae aerobic fed-batch cultures.

    Science.gov (United States)

    Mazzoleni, Stefano; Landi, Carmine; Cartenì, Fabrizio; de Alteriis, Elisabetta; Giannino, Francesco; Paciello, Lucia; Parascandola, Palma

    2015-07-30

    Microbial population dynamics in bioreactors depend on both nutrients availability and changes in the growth environment. Research is still ongoing on the optimization of bioreactor yields focusing on the increase of the maximum achievable cell density. A new process-based model is proposed to describe the aerobic growth of Saccharomyces cerevisiae cultured on glucose as carbon and energy source. The model considers the main metabolic routes of glucose assimilation (fermentation to ethanol and respiration) and the occurrence of inhibition due to the accumulation of both ethanol and other self-produced toxic compounds in the medium. Model simulations reproduced data from classic and new experiments of yeast growth in batch and fed-batch cultures. Model and experimental results showed that the growth decline observed in prolonged fed-batch cultures had to be ascribed to self-produced inhibitory compounds other than ethanol. The presented results clarify the dynamics of microbial growth under different feeding conditions and highlight the relevance of the negative feedback by self-produced inhibitory compounds on the maximum cell densities achieved in a bioreactor.

  3. In vitro fermentation of carbohydrates by porcine faecal inocula and their influence on Salmonella Typhimurium growth in batch culture systems.

    Science.gov (United States)

    Martín-Peláez, Sandra; Gibson, Glenn R; Martín-Orúe, Susana M; Klinder, Annett; Rastall, Robert A; La Ragione, Roberto M; Woodward, Martin J; Costabile, Adele

    2008-12-01

    The aim of this study was to evaluate in vitro the influence of fermentable carbohydrates on the activity of porcine microbiota and survival of Salmonella Typhimurium in a batch culture system simulating the porcine hindgut. The carbohydrates tested were xylooligosaccharides, a mixture of fructooligosaccharides/inulin (FIN), fructooligosaccharides (FOS), gentiooligosaccharides (GEO) and lactulose (LAC). These ingredients stimulated the growth of selected Bifidobacterium and Lactobacillus species in pure cultures. In batch cultures, the carbohydrates influenced some fermentation parameters. For example, GEO and FIN significantly increased lactic acids compared with the control (no added carbohydrate). With the exception of LAC, the test carbohydrates increased the production of short-chain fatty acid (SCFA) and modified SCFA profiles. Quantitative analysis of bacterial populations by FISH revealed increased counts of the Bifidobacterium group compared with control and, with exception of FOS, increased Lactobacillus, Leuconostoc and Weissella spp. counts. Salmonella numbers were the lowest during the fermentation of LAC. This work has looked at carbohydrate metabolism by porcine microbiota in a pH-controlled batch fermentation system. It provides an initial model to analyse interactions with pathogens.

  4. The effect of rhizosphere on growth of Sphingomonas chlorophenolica ATCC 39723 during pentachlorophenol (PCP biodegradation in batch culture and soil

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    Ken Killhan

    2006-12-01

    Full Text Available Studies on the influence of the rhizosphere on the growth of Sphingomonas chlorophenolica during Pentacholophenol (PCP degradation in batch culture and in soil were carried out. In batch culture, a basal minimal medium with or without rhizosphere exudates extracted from winter wheat was used. In soil systems, degradation experiments were performed in the presence and absence of plants. Measurements of PCP concentrations were made using high performance liquid chromatography analysis (HPLC. Bacterial analyses of S. chlorophenolica were carried out by plating on MSM medium. The results showed that the rhizosphere exudates stimulated the growth of the cells of S. chlorophenolica at concentrations of 50 and 80mg kg dry wt soil –1 as well as stimulating the ability of S. chlorophenolica to degrade PCP at a concentration of 80mg Kg dry wt soil -1. In addition, pentachlorophenol had an adverse effect on the growth of S. chlorophenolica. The introduction of S.chlorophenolica into the loamy soil with plants showed a faster degradation when compared to the inoculated soil without plants. There was a significant increase of S. chlorophenolica in the roots in comparison to those in the soil. This study showed that the presence of the inoculum S. chlorophenolica enhanced the PCP degradation in a loamy soil and it indicates the potential for a treatment process under a appropriate environmental conditions such as there present in soil systems.

  5. Degradation of toluene and trichloroethylene by Burkholderia cepacia G4 in growth-limited fed-batch culture

    NARCIS (Netherlands)

    Mars, Astrid E.; Houwing, Joukje; Dolfing, Jan; Janssen, Dick B.

    Burkholderia (Pseudomonas) cepacia G4 was cultivated in a fed-batch bioreactor on either toluene or toluene plus trichloroethylene (TCE), The culture was allowed to reach a constant cell density under conditions in which the amount of toluene supplied equals the maintenance energy demand of the

  6. On the dynamics and constraints of batch culture growth of the cyanobacterium Cyanothece sp. ATCC 51142

    Czech Academy of Sciences Publication Activity Database

    Sinětova, Maria A.; Červený, Jan; Zavřel, Tomáš; Nedbal, Ladislav

    2012-01-01

    Roč. 162, č. 1 (2012), s. 148-155 ISSN 0168-1656 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Keywords : growth limitation * photoprotection * oscillations * Nitrogen fixation * microbial communication Subject RIV: EH - Ecology, Behaviour Impact factor: 3.183, year: 2012

  7. Growth kinetic models of five species of Lactobacilli and lactose consumption in batch submerged culture

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    Fazlollah Rezvani

    Full Text Available Abstract Kinetic behaviors of five Lactobacillus strains were investigated with Contois and Exponential models. Awareness of kinetic behavior of microorganisms is essential for their industrial process design and scale up. The consistency of experimental data was evaluated using Excel software. L. bulgaricus was introduced as the most efficient strain with the highest biomass and lactic acid yield of 0.119 and 0.602 g g-1 consumed lactose, respectively. The biomass and carbohydrate yield of L. fermentum and L. lactis were slightly less and close to L. bulgaricus. Biomass and lactic acid production yield of 0.117 and 0.358 for L. fermentum and 0.114 and 0.437 g g-1 for L.actobacillus lactis were obtained. L. casei and L. delbrueckii had the less biomass yield, nearly 11.8 and 22.7% less than L. bulgaricus, respectively. L. bulgaricus (R 2 = 0.9500 and 0.9156 and L. casei (R 2 = 0.9552 and 0.8401 showed acceptable consistency with both models. The investigation revealed that the above mentioned models are not suitable to describe the kinetic behavior of L. fermentum (R 2 = 0.9367 and 0.6991, L. delbrueckii (R 2 = 0.9493 and 0.7724 and L. lactis (R 2 = 0.8730 and 0.6451. Contois rate equation is a suitable model to describe the kinetic of Lactobacilli. Specific cell growth rate for L. bulgaricus, L. casei, L. fermentum, L. delbrueckii and L. lactis with Contois model in order 3.2, 3.9, 67.6, 10.4 and 9.8-fold of Exponential model.

  8. Growth kinetic models of five species of Lactobacilli and lactose consumption in batch submerged culture.

    Science.gov (United States)

    Rezvani, Fazlollah; Ardestani, Fatemeh; Najafpour, Ghasem

    Kinetic behaviors of five Lactobacillus strains were investigated with Contois and Exponential models. Awareness of kinetic behavior of microorganisms is essential for their industrial process design and scale up. The consistency of experimental data was evaluated using Excel software. L. bulgaricus was introduced as the most efficient strain with the highest biomass and lactic acid yield of 0.119 and 0.602gg -1 consumed lactose, respectively. The biomass and carbohydrate yield of L. fermentum and L. lactis were slightly less and close to L. bulgaricus. Biomass and lactic acid production yield of 0.117 and 0.358 for L. fermentum and 0.114 and 0.437gg -1 for L.actobacillus lactis were obtained. L. casei and L. delbrueckii had the less biomass yield, nearly 11.8 and 22.7% less than L. bulgaricus, respectively. L. bulgaricus (R 2 =0.9500 and 0.9156) and L. casei (R 2 =0.9552 and 0.8401) showed acceptable consistency with both models. The investigation revealed that the above mentioned models are not suitable to describe the kinetic behavior of L. fermentum (R 2 =0.9367 and 0.6991), L. delbrueckii (R 2 =0.9493 and 0.7724) and L. lactis (R 2 =0.8730 and 0.6451). Contois rate equation is a suitable model to describe the kinetic of Lactobacilli. Specific cell growth rate for L. bulgaricus, L. casei, L. fermentum, L. delbrueckii and L. lactis with Contois model in order 3.2, 3.9, 67.6, 10.4 and 9.8-fold of Exponential model. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  9. Using Raman spectroscopy and chemometrics to identify the growth phase of Lactobacillus casei Zhang during batch culture at the single-cell level.

    Science.gov (United States)

    Ren, Yan; Ji, Yuetong; Teng, Lin; Zhang, Heping

    2017-12-23

    As microbial cultures are comprised of heterogeneous cells that differ according to their size and intracellular concentrations of DNA, proteins, and other constituents, the detailed identification and discrimination of the growth phases of bacterial populations in batch culture is challenging. Cell analysis is indispensable for quality control and cell enrichment. In this paper, we report the results of our investigation on the use of single-cell Raman spectrometry (SCRS) for real-time analysis and prediction of cells in different growth phases during batch culture of Lactobacillus (L.) casei Zhang. A targeted analysis of defined cell growth phases at the level of the single cell, including lag phase, log phase, and stationary phase, was facilitated by SCRS. Spectral shifts were identified in different states of cell growth that reflect biochemical changes specific to each cell growth phase. Raman peaks associated with DNA and RNA displayed a decrease in intensity over time, whereas protein-specific and lipid-specific Raman vibrations increased at different rates. Furthermore, a supervised classification model (Random Forest) was used to specify the lag phase, log phase, and stationary phase of cells based on SCRS, and a mean sensitivity of 90.7% and mean specificity of 90.8% were achieved. In addition, the correct cell type was predicted at an accuracy of approximately 91.2%. To conclude, Raman spectroscopy allows label-free, continuous monitoring of cell growth, which may facilitate more accurate estimates of the growth states of lactic acid bacterial populations during fermented batch culture in industry.

  10. Ethanol effect on batch and fed-batch Arthrospira platensis growth.

    Science.gov (United States)

    Bezerra, Raquel P; Matsudo, Marcelo C; Pérez Mora, Lina S; Sato, Sunao; de Carvalho, João C Monteiro

    2014-04-01

    The ability of Arthrospira platensis to use ethanol as a carbon and energy source was investigated by batch process and fed-batch process. A. platensis was cultivated under the effect of a single addition (batch process) and a daily pulse feeding (fed-batch process) of pure ethanol, at different concentrations, to evaluate cell concentration (X) and specific growth rate (μ). A marked increase was observed in the cell concentration of A. platensis in runs with ethanol addition when compared to control cultures without ethanol addition. The fed-batch process using an ethanol concentration of 38 mg L(-1) days(-1) reached the maximum cell concentration of 2,393 ± 241 mg L(-1), about 1.5-fold that obtained in the control culture. In all experiments, the maximum specific growth rate was observed in the early exponential phase of cell growth. In the fed-batch process, μ decreased more slowly than in the batch process and control culture, resulting in the highest final cell concentration. Ethanol can be used as a feasible carbon and energy source for A. platensis growth via a fed-batch process.

  11. Fermentative and growth performances of Dekkera bruxellensis in different batch systems and the effect of initial low cell counts in co-cultures with Saccharomyces cerevisiae.

    Science.gov (United States)

    Meneghin, Maria Cristina; Bassi, Ana Paula Guarnieri; Codato, Carolina Brito; Reis, Vanda Renata; Ceccato-Antonini, Sandra Regina

    2013-08-01

    Dekkera bruxellensis is a multifaceted yeast present in the fermentative processes used for alcoholic beverage and fuel alcohol production - in the latter, normally regarded as a contaminant. We evaluated the fermentation and growth performance of a strain isolated from water in an alcohol-producing unit, in batch systems with/without cell recycling in pure and co-cultures with Saccharomyces cerevisiae. The ethanol resistance and aeration dependence for ethanol/acid production were verified. Ethanol had an effect on the growth of D. bruxellensis in that it lowered or inhibited growth depending on the concentration. Acid production was verified in agitated cultures either with glucose or sucrose, but more ethanol was produced with glucose in agitated cultures. Regardless of the batch system, low sugar consumption and alcohol production and expressive growth were found with D. bruxellensis. Despite a similar ethanol yield compared to S. cerevisiae in the batch system without cell recycling, ethanol productivity was approximately four times lower. However, with cell recycling, ethanol yield was almost half that of S. cerevisiae. At initial low cell counts of D. bruxellensis (10 and 1000 cells/ml) in co-cultures with S. cerevisiae, a decrease in fermentative efficiency and a substantial growth throughout the fermentative cycles were displayed by D. bruxellensis. Due to the peculiarity of cell repitching in Brazilian fermentation processes, D. bruxellensis is able to establish itself in the process, even when present in low numbers initially, substantially impairing bioethanol production due to the low ethanol productivity, in spite of comparable ethanol yields. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Endoplasmic Reticulum-Associated rht-PA Processing in CHO Cells: Influence of Mild Hypothermia and Specific Growth Rates in Batch and Chemostat Cultures.

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    Mauricio Vergara

    Full Text Available Chinese hamster ovary (CHO cells are the main host for producing recombinant proteins with human therapeutic applications mainly because of their capability to perform proper folding and glycosylation processes. In addition, mild hypothermia is one of the main strategies for maximising the productivity of these systems. However, little information is available on the effect of culture temperature on the folding and degradation processes of recombinant proteins that takes place in the endoplasmic reticulum.In order to evaluate the effect of the mild hypothermia on processing/endoplasmatic reticulum-associated degradation (ERAD processes, batch cultures of CHO cells producing recombinant human tissue plasminogen activator (rht-PA were carried out at two temperatures (37°C and 33°C and treated with specific inhibitors of glycosylation and ERAD I (Ubiquitin/Proteasome system or ERAD II (Autophagosoma/Lisosomal system pathways. The effect of mild hypothermia was analysed separately from its indirect effect on specific cell growth rate. To do this, chemostat cultures were carried out at the same incubation conditions as the batch cultures, controlling cell growth at high (0.017 h-1 and low (0.012 h-1 dilution rates. For a better understanding of the investigated phenomenon, cell behaviour was also analysed using principal component analysis (PCA.Results suggest that rht-PA is susceptible to degradation by both ERAD pathways studied, revealing that processing and/or ERAD processes are sensitive to temperature cultivation in batch culture. Moreover, by isolating the effect of culture temperature from the effect of cell growth rate verifyed by using chemostat cultures, we have found that processing and/or ERAD processes are more sensitive to reduction in specific growth rate than low temperature, and that temperature reduction may have a positive effect on protein processing. Interestingly, PCA indicated that the integrated performance displayed by CHO

  13. The effect of growth phase on the lipid class, fatty acid and sterol composition in the marine dinoflagellate, Gymnodinium sp. in batch culture.

    Science.gov (United States)

    Mansour, Maged P; Volkman, John K; Blackburn, Susan I

    2003-05-01

    We have studied the effects of growth phase on the lipid composition in batch cultures of Gymnodinium sp. CS-380/3 over 43 days of culturing. The lipid content increased two fold, from late logarithmic (day 6) to linear growth phase (day 22) then decreased at stationary phase (day 43) while the lipid yield (mg l(-1)) increased 30-fold from day 6 to 30 mg l(-1) at day 43. Changes in fatty acid content mirrored those observed for the total lipid, while the sterol content continued to increase with culture age through to stationary phase. The largest changes occurred in the lipid classes, especially the polar lipids and triacylglycerols (oil). The proportion of triacylglycerols increased from 8% (of total lipids) at day 6 to 30% at day 43, with a concomitant decrease in the polar lipid fraction. The proportions of 16:0 and DHA [22:6(n-3)] increased while those of 18:5(n-3) and EPA [20:5(n-3)] decreased with increasing culture age. The proportion of the major sterol, dinosterol, decreased from 41% (day 6) to 29% (day 43), while the major dinostanol epimer (23R,24R) increased from 33% (day 6) to 38% (day 22). Despite small changes in the proportion of the main sterols, the same sterols were present at all stages of growth, indicating their value as a chemotaxonomic tool for distinguishing between strains within the same genus. Growth phase could be a useful variable for optimising the oil and DHA content with potential for aquaculture feeds and a source of DHA-rich oils for nutraceuticals.

  14. In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

    Science.gov (United States)

    El-Hawaz, Rabia F.; Bridges, William C.; Adelberg, Jeffrey W.

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments’ macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes. PMID:25830292

  15. In vitro growth of Curcuma longa L. in response to five mineral elements and plant density in fed-batch culture systems.

    Science.gov (United States)

    El-Hawaz, Rabia F; Bridges, William C; Adelberg, Jeffrey W

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments' macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes.

  16. CHANGES IN CHLOROPHYLL A FLOURESCENCE AND PIGMENT RATIOS DURING DIFFERENT GROWTH PHASES OF A UNICELLULAR MARINE CHAETOCEROS (BACILLAROPHYCEAE) IN BATCH CULTURE

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    Interpretations of chlorophyll a fluorescence data are based largely on application with green algae and higher plants. This study evaluated the interpretation of fluorescence data for a unicellular marine diatom. Chaetoceros sp. was grown in 4-liter batch cultures on a 16:8, L:D...

  17. Growth and nitrogen removal capacity of Desmodesmus communis and of a natural microalgae consortium in a batch culture system in view of urban wastewater treatment: part I.

    Science.gov (United States)

    Samorì, Giulia; Samorì, Chiara; Guerrini, Franca; Pistocchi, Rossella

    2013-02-01

    The microalgal biomass applications strongly depend on cell composition and the production of low cost products such as biofuels appears to be economically convenient only in conjunction with wastewater treatment. As a preliminary study, in view of the development of a wastewater treatment pilot plant for nutrient removal and algal biomass production, a biological wastewater system was carried out on a laboratory scale growing a newly isolated freshwater algal strain, Desmodesmus communis, and a natural consortium of microalgae in effluents generated by a local wastewater reclamation facility. Batch cultures were operated by using D. communis under different growth conditions to better understand the effects of CO₂, nutrient concentration and light intensity on the biomass productivity and biochemical composition. The results were compared with those obtained using a natural algal consortium. D. communis showed a great vitality in the wastewater effluents with a biomass productivity of 0.138-0.227 g L⁻¹ d⁻¹ in the primary effluent enriched with CO₂, higher biomass productivity compared with the one achieved by the algal consortium (0.078 g L⁻¹ d⁻¹). D. communis cultures reached also a better nutrient removal efficiency compared with the algal consortium culture, with almost 100% for ammonia and phosphorous at any N/P ratio characterizing the wastewater nutrient composition. Biomass composition was richer in polysaccharides and total fatty acids as the ammonia concentration in the water decreased. In view of a future application of this algal biomass, due to the low total fatty acids content of 1.4-9.3 wt% and the high C/N ratio of 7.6-39.3, anaerobic digestion appeared to be the most appropriate biofuel conversion process. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Nucleation and crystal growth in batch crystallizers

    NARCIS (Netherlands)

    Janse, A.H.

    1977-01-01

    The aim of the present work is to gain knowledge of the mechanism of formation of the crystal size distribution in batch crystallizers in order to give directives for design and operation of batch crystallizers. The crystal size distribution is important for the separation of crystals and mother

  19. Comprehensive modeling and investigation of the effect of iron on the growth rate and lipid accumulation of Chlorella vulgaris cultured in batch photobioreactors.

    Science.gov (United States)

    Concas, Alessandro; Steriti, Alberto; Pisu, Massimo; Cao, Giacomo

    2014-02-01

    Recent works have shown that specific strains of microalgae are capable to simultaneously increase their growth rate and lipid content when cultured under suitable concentrations of iron. While these results are promising in view of the exploitation of microalgae for producing biofuels, to the best of our knowledge, no mathematical model capable to describe the effect of iron on lipid accumulation in microalgae, has been so far proposed. A comprehensive mathematical model describing the effect of iron on chlorophyll synthesis, nitrogen assimilation, growth rate and lipid accumulation in a freshwater strain of Chlorella vulgaris is then proposed in this work. Model results are successfully compared with experimental data which confirm the positive effect of growing iron concentrations on lipid productivity of C. vulgaris. Thus, the proposed model might represent a useful tool to optimize iron-based strategies to improve the lipid productivity of microalgal cultures. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Optimization of the Production of Polygalacturonase from Aspergillus kawachii Cloned in Saccharomyces cerevisiae in Batch and Fed-Batch Cultures

    Directory of Open Access Journals (Sweden)

    Diego Jorge Baruque

    2011-01-01

    Full Text Available Polygalacturonases (PG; EC 3.2.1.15 catalyze the hydrolysis of pectin and/or pectic acid and are useful for industrial applications such as juice clarification and pectin extraction. Growth and heterologous expression of recombinant Saccharomyces cerevisiae which expresses an acidic PG from Aspergillus kawachii has been studied in batch and fed-batch cultures. Kinetics and stoichiometric parameters of the recombinant yeast were determined in batch cultures in a synthetic medium. In these cultures, the total biomass concentration, protein concentration, and enzyme activity achieved were 2.2 g/L, 10 mg/L, and 3 U/mL, respectively, to give a productivity of 0.06 U/(mL·h. In fed-batch cultures, various strategies for galactose feeding were used: (i after a glucose growth phase, the addition of a single pulse of galactose which gave a productivity of 0.19 U/(mL·h; (ii after a glucose growth phase, a double pulse of galactose at the same final concentration was added, resulting in a productivity of 0.21 U/(mL·h; (iii a simultaneous feeding of glucose and galactose, yielding a productivity of 1.32 U/(mL·h. Based on these results, the simultaneous feeding of glucose and galactose was by far the most suitable strategy for the production of this enzyme. Moreover, some biochemical characteristics of the recombinant enzyme such as a molecular mass of ~60 kDa, an isoelectric point of 3.7 and its ability to hydrolyze polygalacturonic acid at pH=2.5 were determined.

  1. Medium optimization for protopectinase production by batch culture of

    African Journals Online (AJOL)

    Medium optimization for protopectinase production by batch culture of. C Fan, Z Liu, L Yao. Abstract. Optimization of medium compositions for protopectinase production by Aspergillus terreus in submerged culture was carried out. The medium components having significant effect on protopectinase production were reported ...

  2. Batch variation between branchial cell cultures: An analysis of variance

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Grosell, M.; Kristensen, L.

    2003-01-01

    We present in detail how a statistical analysis of variance (ANOVA) is used to sort out the effect of an unexpected batch-to-batch variation between cell cultures. Two separate cultures of rainbow trout branchial cells were grown on permeable filtersupports ("inserts"). They were supposed...... to be simple duplicates for testing the effect of two induced factors-apical or basolateral addition of radioactive precursors and different apical media-on the incorporation of 14C-acetate and 32Pphosphate intotissue lipids. Unfortunately, they did not altogether give the same result. By accepting this fact...... and introducing the observed difference between batches as one of the factors in an expanded three-dimensional ANOVA, we were able to overcome an otherwisecrucial lack of sufficiently reproducible duplicate values. We could thereby show that the effect of changing the apical medium was much more marked when...

  3. Stochastic growth logistic model with aftereffect for batch fermentation process

    International Nuclear Information System (INIS)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-01-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits

  4. Stochastic growth logistic model with aftereffect for batch fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Norhayati; Ayoubi, Tawfiqullah [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah; Rahman, Haliza Abdul [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  5. Defined medium for Aquaspirillum serpens VHL effective in batch and continuous culture.

    Science.gov (United States)

    Whitby, G E; Murray, R G

    1980-01-01

    A defined medium for Aquaspirillum serpens VHL allows the replacement of the complex media now in use. It was developed by batch culture methods but supports growth in continuous culture. A basal salts medium supplemented with L-aspartic acid, L-alanine, and L-glutamic acid provided the best growth (turbidity), as long as ammonium chloride was omitted. Ammonium chloride caused either a lag or a reduction or a complete inhibition of the growth of A. serpens VHL on the above amino acids and other organic supplements depending on the combination used. Ammonium sulfate and ammonium hydroxide with L-glutamic acid allowed growth, but the lag period was increased in shake flask cultures. Vitamins, cysteine hydrochloride, and carbon dioxide had no effect on the growth rate. Viability (less than 50%) was inadequate to maintain continuous culture with L-glutamic acid as the sole source of carbon and nitrogen. Combinations of amino and carboxylic acids were then tested and, of these, L-glutamic acid (1 g/liter) and L-histidine (75 mg/liter) without ammonium chloride in the basal salts medium supported growth in batch and continuous culture. L-Glutamic acid was the limiting substrate for growth.

  6. Oxygen availability strongly affects chronological lifespan and thermotolerance in batch cultures of Saccharomyces cerevisiae

    Science.gov (United States)

    Bisschops, Markus M.; Vos, Tim; Martínez-Moreno, Rubén; Cortés, Pilar T.; Pronk, Jack T.; Daran-Lapujade, Pascale

    2015-01-01

    Stationary-phase (SP) batch cultures of Saccharomyces cerevisiae, in which growth has been arrested by carbon-source depletion, are widely applied to study chronological lifespan, quiescence and SP-associated robustness. Based on this type of experiments, typically performed under aerobic conditions, several roles of oxygen in aging have been proposed. However, SP in anaerobic yeast cultures has not been investigated in detail. Here, we use the unique capability of S. cerevisiae to grow in the complete absence of oxygen to directly compare SP in aerobic and anaerobic bioreactor cultures. This comparison revealed strong positive effects of oxygen availability on adenylate energy charge, longevity and thermotolerance during SP. A low thermotolerance of anaerobic batch cultures was already evident during the exponential growth phase and, in contrast to the situation in aerobic cultures, was not substantially increased during transition into SP. A combination of physiological and transcriptome analysis showed that the slow post-diauxic growth phase on ethanol, which precedes SP in aerobic, but not in anaerobic cultures, endowed cells with the time and resources needed for inducing longevity and thermotolerance. When combined with literature data on acquisition of longevity and thermotolerance in retentostat cultures, the present study indicates that the fast transition from glucose excess to SP in anaerobic cultures precludes acquisition of longevity and thermotolerance. Moreover, this study demonstrates the importance of a preceding, calorie-restricted conditioning phase in the acquisition of longevity and stress tolerance in SP yeast cultures, irrespective of oxygen availability. PMID:28357268

  7. Oxygen availability strongly affects chronological lifespan and thermotolerance in batch cultures of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Markus M.M. Bisschops

    2015-10-01

    Full Text Available Stationary-phase (SP batch cultures of Saccharomyces cerevisiae, in which growth has been arrested by carbon-source depletion, are widely applied to study chronological lifespan, quiescence and SP-associated robustness. Based on this type of experiments, typically performed under aerobic conditions, several roles of oxygen in aging have been proposed. However, SP in anaerobic yeast cultures has not been investigated in detail. Here, we use the unique capability of S. cerevisiae to grow in the complete absence of oxygen to directly compare SP in aerobic and anaerobic bioreactor cultures. This comparison revealed strong positive effects of oxygen availability on adenylate energy charge, longevity and thermotolerance during SP. A low thermotolerance of anaerobic batch cultures was already evident during the exponential growth phase and, in contrast to the situation in aerobic cultures, was not substantially increased during transition into SP. A combination of physiological and transcriptome analysis showed that the slow post-diauxic growth phase on ethanol, which precedes SP in aerobic, but not in anaerobic cultures, endowed cells with the time and resources needed for inducing longevity and thermotolerance. When combined with literature data on acquisition of longevity and thermotolerance in retentostat cultures, the present study indicates that the fast transition from glucose excess to SP in anaerobic cultures precludes acquisition of longevity and thermotolerance. Moreover, this study demonstrates the importance of a preceding, calorie-restricted conditioning phase in the acquisition of longevity and stress tolerance in SP yeast cultures, irrespective of oxygen availability.

  8. CHANGES IN CHLOROPHYLL A FLUORENSCENCE AND PIGMENT RATIOS DURING DIFFERENT GROWTH PHASES OF A UNICELLULAR MARINE CHEATOSEROS (BACILLARIOPHYCEAE) IN BATCH CULTURE

    Science.gov (United States)

    Photosystem II reaction centers per cell decreased as the cultures began to decline. The degree of inactivation increased daily as the cell numbers continued to decrease. The concentration of chlorophyll a per cell and the ratio of the major accessory pigments to chlorophyll a (e...

  9. Increasing the production of desulfurizing biocatalysts by means of fed - batch culture

    International Nuclear Information System (INIS)

    Berdugo, C I; Mena, J A; Acero, J R; Mogollon, L

    2001-01-01

    Over the past years, environmental regulations have driven a lot of effort for the development of new technologies for the upgrading of fossil fuels. Biotechnology offers an alternative way to process fossil fuels by means of a biodesulfurization technology where the production of the biocatalyst is one of the key topics. Traditionally, the production is carried out in batch culture where the maximum cellular concentration is restricted by inherent limitations of the culture type and the microorganism growth rate. This work addresses the production of two desulfurizing microorganisms: Rhodococcus erythropolis IGTS8 and gordona rubropertinctus ICP172 using fed-batch culture. Fed-batch cultures were conducted in a 12 L fermentor using ICP 4 medium containing glucose and DMSO as carbon and sulfur sources. As a result, cell concentration was increased 1.5 and 3 times with fed-batch cultures using constant and exponential flow respectively, achieving a maximum cell concentration of 7.3 g DCW/L of biocatalyst igts8 and 12.85 gGDCW/L of the new biocatalyst ICP172. Both biocatalysts presented biodesulfurization activity in a spiked matrix DBT/HXD and in diesel matrix with the detection of 2-HBP which is the end-product of DBT degradation pathway

  10. Endoplasmic Reticulum-Associated rht-PA Processing in CHO Cells: Influence of Mild Hypothermia and Specific Growth Rates in Batch and Chemostat Cultures

    OpenAIRE

    Vergara, Mauricio; Berrios, Julio; Mart?nez, Irene; D?az-Barrera, Alvaro; Acevedo, Cristian; Reyes, Juan G.; Gonzalez, Ramon; Altamirano, Claudia

    2015-01-01

    Background Chinese hamster ovary (CHO) cells are the main host for producing recombinant proteins with human therapeutic applications mainly because of their capability to perform proper folding and glycosylation processes. In addition, mild hypothermia is one of the main strategies for maximising the productivity of these systems. However, little information is available on the effect of culture temperature on the folding and degradation processes of recombinant proteins that takes place in ...

  11. Identifying yeast isolated from spoiled peach puree and assessment of its batch culture for invertase production

    Directory of Open Access Journals (Sweden)

    Marcela Vega FERREIRA

    Full Text Available Abstract The identification of yeasts isolated from spoiled Jubileu peach puree using the API 20C AUX method and a commercial yeast as witness were studied. Subsequently, the yeast’s growth potential using two batch culture treatments were performed to evaluate number of colonies (N, reducing sugar concentration (RS, free-invertase (FI, and culture-invertase activity (CI. Stock cultures were maintained on potato dextrose agar (PDA slants at 4 °C and pH 5 for later use for batch-culture (150 rpm at 30°C for 24 h, then they were stored at 4 °C for subsequent invertase extraction. The FI extract was obtained using NaHCO3 as autolysis agent, and CI activity was determined on the supernatant after batch-cultured centrifugation. The activity was followed by an increase in absorbance at 490 nm using the acid 3,5-DNS method with glucose standard. Of the four yeasts identified, Saccharomyces cerevisiae was chosen for legal reasons. It showed logarithmic growth up to 18 h of fermentation with positive correlation CI activity and inverse with RS. FI showed greater activity by the end of the log phase and an inverse correlation with CI activity. Finally, it was concluded that treatment “A” is more effective than “B” to produce invertase (EC 3.2.1.26.

  12. Hypoxia-elicited impairment of cell wall integrity, glycosylation precursor synthesis, and growth in scaled-up high-cell density fed-batch cultures of Saccharomyces cerevisiae.

    Science.gov (United States)

    Aon, Juan C; Sun, Jianxin; Leighton, Julie M; Appelbaum, Edward R

    2016-08-15

    In this study we examine the integrity of the cell wall during scale up of a yeast fermentation process from laboratory scale (10 L) to industrial scale (10,000 L). In a previous study we observed a clear difference in the volume fraction occupied by yeast cells as revealed by wet cell weight (WCW) measurements between these scales. That study also included metabolite analysis which suggested hypoxia during scale up. Here we hypothesize that hypoxia weakens the yeast cell wall during the scale up, leading to changes in cell permeability, and/or cell mechanical resistance, which in turn may lead to the observed difference in WCW. We tested the cell wall integrity by probing the cell wall sensitivity to Zymolyase. Also exometabolomics data showed changes in supply of precursors for the glycosylation pathway. The results show a more sensitive cell wall later in the production process at industrial scale, while the sensitivity at early time points was similar at both scales. We also report exometabolomics data, in particular a link with the protein glycosylation pathway. Significantly lower levels of Man6P and progressively higher GDP-mannose indicated partially impaired incorporation of this sugar nucleotide during co- or post-translational protein glycosylation pathways at the 10,000 L compared to the 10 L scale. This impairment in glycosylation would be expected to affect cell wall integrity. Although cell viability from samples obtained at both scales were similar, cells harvested from 10 L bioreactors were able to re-initiate growth faster in fresh shake flask media than those harvested from the industrial scale. The results obtained help explain the WCW differences observed at both scales by hypoxia-triggered weakening of the yeast cell wall during the scale up.

  13. Salt-induced osmotic stress for lipid overproduction in batch culture ...

    African Journals Online (AJOL)

    Effect of NaCl-induced osmotic stress on lipid production was investigated in batch culture of Chlorella vulgaris. Based on the facts that NaCl stress improved lipid production but inhibited cells growth at the same times, the novel strategies of multiple osmotic stresses with different NaCl additions (2 g/L at 80 h, 4 g/L at 100 h, ...

  14. Perfusion seed cultures improve biopharmaceutical fed-batch production capacity and product quality.

    Science.gov (United States)

    Yang, William C; Lu, Jiuyi; Kwiatkowski, Chris; Yuan, Hang; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2014-01-01

    Volumetric productivity and product quality are two key performance indicators for any biopharmaceutical cell culture process. In this work, we showed proof-of-concept for improving both through the use of alternating tangential flow perfusion seed cultures coupled with high-seed fed-batch production cultures. First, we optimized the perfusion N-1 stage, the seed train bioreactor stage immediately prior to the production bioreactor stage, to minimize the consumption of perfusion media for one CHO cell line and then successfully applied the optimized perfusion process to a different CHO cell line. Exponential growth was observed throughout the N-1 duration, reaching >40 × 10(6) vc/mL at the end of the perfusion N-1 stage. The cultures were subsequently split into high-seed (10 × 10(6) vc/mL) fed-batch production cultures. This strategy significantly shortened the culture duration. The high-seed fed-batch production processes for cell lines A and B reached 5 g/L titer in 12 days, while their respective low-seed processes reached the same titer in 17 days. The shortened production culture duration potentially generates a 30% increase in manufacturing capacity while yielding comparable product quality. When perfusion N-1 and high-seed fed-batch production were applied to cell line C, higher levels of the active protein were obtained, compared to the low-seed process. This, combined with correspondingly lower levels of the inactive species, can enhance the overall process yield for the active species. Using three different CHO cell lines, we showed that perfusion seed cultures can optimize capacity utilization and improve process efficiency by increasing volumetric productivity while maintaining or improving product quality. © 2014 American Institute of Chemical Engineers.

  15. Batch culture of Azotobacter vinelandii under oxygen limitation conditionS

    Energy Technology Data Exchange (ETDEWEB)

    Camacho Rubio, F.; Martinez Nieto, L.; Fernandez Serrano, M.; Jimenez Moleon, M.C. [Departamento de Ingenieria Quimica, Universidad de Granada, Granada (Spain)

    1996-12-01

    The batch culture of Azotobacter vinealandii on glucose under nitrogen-fixing conditions, seeking oxygen limitation conditions, has been studied in order to use it as a Biological Test System for the experimental study of oxygen transfer enhancement methods in aerobic fermenters. overall kinetic parameters for exponential growth and for linear growth (under oxygen limitation) have been determined. It was noted an appreciable influence of the oxygen transfer rate on glucose and oxygen uptake, which seems to be due to alginate production, excreted as a nitrogenase protection mechanisms. (Author) 12 refs.

  16. Xylitol production by Candida parapsilosis under fed-batch culture

    Directory of Open Access Journals (Sweden)

    Sandra A. Furlan

    2001-06-01

    Full Text Available Xylitol production by Candida parapsilosis was investigated under fed-batch cultivation, using single (xylose or mixed (xylose and glucose sugars as substrates. The presence of glucose in the medium induced the production of ethanol as secondary metabolite and improved specific rates of growth, xylitol formation and substrate consumption. Fractionated supply of the feed medium at constant sugar concentration did not promote any increase on the productivity compared to the single batch cultivation.A produção de xylitol por Candida parapsilosis foi investigada em regime de batelada alimentada, usando substratos açucarados de composição simples (xilose ou composta (xilose e glicose. A presença de glicose no meio induziu a formação de etanol como metabólito secundário. A suplementação fracionada do meio de alimentação numa concentração fixa de açúcar não resultou em aumento da produtividade em relação àquela alcançada em batelada simples.

  17. MASS PRODUCTION OF THE BENEFICIAL NEMATODE STEINERNEMA CARPOCAPSAE UTILIZING A FED-BATCH CULTURING PROCESS

    OpenAIRE

    Leonard D. Holmes; Floyd L. Inman III; Sivanadane Mandjiny; Rinu Kooliyottil; Devang Upadhyay

    2013-01-01

    The present study deals with the batch and fed-batch mass production of Steinernema carpocapsae. S. carpocapsae is an entomoparasitic nematode that is used as a biological control agent of soil-borne crop insect pests. The ability and efficiency of fed-batch culture process was successful through the utilization of the nematode’s bacterial symbiont Xenorhabdus nematophila. Results from the fed-batch process were compared to those obtain from the standard batch process. The fed-batch process s...

  18. A framework for the systematic design of fed-batch strategies in mammalian cell culture.

    Science.gov (United States)

    Kyriakopoulos, Sarantos; Kontoravdi, Cleo

    2014-12-01

    A methodology to calculate the required amount of amino acids (a.a.) and glucose in feeds for animal cell culture from monitoring their levels in batch experiments is presented herein. Experiments with the designed feeds on an antibody-producing Chinese hamster ovary cell line resulted in a 3-fold increase in titer compared to batch culture. Adding 40% more nutrients to the same feed further increases the yield to 3.5 higher than in batch culture. Our results show that above a certain threshold there is no linear correlation between nutrient addition and the integral of viable cell concentration. In addition, although high ammonia levels hinder cell growth, they do not appear to affect specific antibody productivity, while we hypothesize that high extracellular lactate concentration is the cause for the metabolic shift towards lactate consumption for the cell line used. Overall, the performance of the designed feeds is comparable to that of a commercial feed that was tested in parallel. Expanding this approach to more nutrients, as well as changing the ratio of certain amino acids as informed by flux balance analysis, could achieve even higher yields. © 2014 Wiley Periodicals, Inc.

  19. Algae for controlled ecological life support system diet characterization of cyanobacteria 'spirulina' in batch cultures

    Science.gov (United States)

    Tadros, M. G.

    1990-01-01

    Spirulina sp. is a bioregenerative photosynthetic and edible alga for space craft crews in a Closed Ecological Life Support System (CLESS). It was characterized for growth rate and biomass yield in batch cultures, under various environmental conditions. The cell characteristics were identified for one strain of Spirulina: S. maxima. Fast growth rate and high yield were obtained. The partitioning of the assimulatory products (proteins, carbohydrates, lipids) were manipulated by varying the environmental conditions. Experiments with Spirulina demonstrated that under stress conditions carbohydrate increased at the expense of protein. In other experiments, where the growth media were sufficient in nutrients and incubated under optimum growth conditions, the total proteins were increased up to almost 70 percent of the organic weight. In other words, the nutritional quality of the alga could be manipulated by growth conditions. These results support the feasibility of considering Spirulina as a subsystem in CELSS because of the ease with which its nutrient content can be manipulated.

  20. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process...

  1. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

    Directory of Open Access Journals (Sweden)

    Wiebe Marilyn G

    2012-05-01

    Full Text Available Abstract Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100 media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1 as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass. Lipid production was low (15–19% lipid in biomass with arabinose as sole carbon source and was lower than expected (30% lipid in biomass when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed

  2. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates.

    Science.gov (United States)

    Wiebe, Marilyn G; Koivuranta, Kari; Penttilä, Merja; Ruohonen, Laura

    2012-05-30

    Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100) media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Lipid production was most efficient with glucose (up to 25 g lipid L(-1), 48 to 75% lipid in the biomass, at up to 0.21 g lipid L(-1) h(-1)) as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass). Lipid production was low (15-19% lipid in biomass) with arabinose as sole carbon source and was lower than expected (30% lipid in biomass) when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L(-1), with 49% lipid in the biomass) and fed-batch (35 to 47 g L(-1), with 50 to 75% lipid in the biomass) cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Lipid production in R. toruloides was lower from arabinose and mixed carbohydrates than from glucose or xylose. Although high biomass and lipid

  3. Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture

    Directory of Open Access Journals (Sweden)

    Živan Gojkovic

    2014-01-01

    Full Text Available The aim of this work was to study the effect of Se(+VI on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L−1 (212 μM decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg·L−1 (238.2 μM was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg·kg−1 of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.

  4. Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture

    Science.gov (United States)

    Vílchez, Carlos; Torronteras, Rafael; Vigara, Javier; Gómez-Jacinto, Veronica; Janzer, Nora; Gómez-Ariza, José-Luis; Márová, Ivana

    2014-01-01

    The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L−1 (212 μM) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg·L−1 (238.2 μM) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg·kg−1 of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se. PMID:24688385

  5. Pseudomonas aeruginosa PAO1 Preferentially Grows as Aggregates in Liquid Batch Cultures and Disperses upon Starvation

    Science.gov (United States)

    Schleheck, David; Barraud, Nicolas; Klebensberger, Janosch; Webb, Jeremy S.; McDougald, Diane; Rice, Scott A.; Kjelleberg, Staffan

    2009-01-01

    In both natural and artificial environments, bacteria predominantly grow in biofilms, and bacteria often disperse from biofilms as freely suspended single-cells. In the present study, the formation and dispersal of planktonic cellular aggregates, or ‘suspended biofilms’, by Pseudomonas aeruginosa in liquid batch cultures were closely examined, and compared to biofilm formation on a matrix of polyester (PE) fibers as solid surface in batch cultures. Plankton samples were analyzed by laser-diffraction particle-size scanning (LDA) and microscopy of aggregates. Interestingly, LDA indicated that up to 90% of the total planktonic biomass consisted of cellular aggregates in the size range of 10–400 µm in diameter during the growth phase, as opposed to individual cells. In cultures with PE surfaces, P. aeruginosa preferred to grow in biofilms, as opposed to planktonicly. However, upon carbon, nitrogen or oxygen limitation, the planktonic aggregates and PE-attached biofilms dispersed into single cells, resulting in an increase in optical density (OD) independent of cellular growth. During growth, planktonic aggregates and PE-attached biofilms contained densely packed viable cells and extracellular DNA (eDNA), and starvation resulted in a loss of viable cells, and an increase in dead cells and eDNA. Furthermore, a release of metabolites and infective bacteriophage into the culture supernatant, and a marked decrease in intracellular concentration of the second messenger cyclic di-GMP, was observed in dispersing cultures. Thus, what traditionally has been described as planktonic, individual cell cultures of P. aeruginosa, are in fact suspended biofilms, and such aggregates have behaviors and responses (e.g. dispersal) similar to surface associated biofilms. In addition, we suggest that this planktonic biofilm model system can provide the basis for a detailed analysis of the synchronized biofilm life cycle of P. aeruginosa. PMID:19436737

  6. Investigation of vinegar production using a novel shaken repeated batch culture system.

    Science.gov (United States)

    Schlepütz, Tino; Büchs, Jochen

    2013-01-01

    Nowadays, bioprocesses are developed or optimized on small scale. Also, vinegar industry is motivated to reinvestigate the established repeated batch fermentation process. As yet, there is no small-scale culture system for optimizing fermentation conditions for repeated batch bioprocesses. Thus, the aim of this study is to propose a new shaken culture system for parallel repeated batch vinegar fermentation. A new operation mode - the flushing repeated batch - was developed. Parallel repeated batch vinegar production could be established in shaken overflow vessels in a completely automated operation with only one pump per vessel. This flushing repeated batch was first theoretically investigated and then empirically tested. The ethanol concentration was online monitored during repeated batch fermentation by semiconductor gas sensors. It was shown that the switch from one ethanol substrate quality to different ethanol substrate qualities resulted in prolonged lag phases and durations of the first batches. In the subsequent batches the length of the fermentations decreased considerably. This decrease in the respective lag phases indicates an adaptation of the acetic acid bacteria mixed culture to the specific ethanol substrate quality. Consequently, flushing repeated batch fermentations on small scale are valuable for screening fermentation conditions and, thereby, improving industrial-scale bioprocesses such as vinegar production in terms of process robustness, stability, and productivity. Copyright © 2013 American Institute of Chemical Engineers.

  7. Testing alternative kinetic models for utilization of crystalline cellulose (Avicel) by batch cultures of Clostridium thermocellum.

    Science.gov (United States)

    Holwerda, Evert K; Lynd, Lee R

    2013-09-01

    Descriptive kinetics of batch cellulose (Avicel) and cellobiose fermentation by Clostridium thermocellum were examined with residual substrate and biosynthate concentrations inferred based on elemental analysis. Biosynthate was formed in constant proportion to substrate consumption until substrate was exhausted for cellobiose fermentation, and until near the point of substrate exhaustion for cellulose fermentation. Cell yields (g pellet biosynthate carbon/g substrate carbon) of 0.214 and 0.200 were obtained for cellulose and cellobiose, respectively. For cellulose fermentation a sigmoidal curve fit was applied to substrate and biosynthate concentrations over time, which was then differentiated to calculate instantaneous rates of growth and substrate consumption. Three models were tested to describe the kinetics of Avicel utilization by C. thermocellum: (A) first order in cells, (B) first order in substrate, and (C) first order in cells and substrate, and second order overall. Models (A) and (B) have been proposed in the literature to describe cultures of cellulolytic microorganisms, whereas model (C) has not. Of the three models tested, model (c) provided by far the best fit to batch culture data. A second order rate constant equal to 0.735 L g C(-1)  h(-1) was found for utilization of Avicel by C. thermocellum. Adding an endogenous metabolism term improved the descriptive quality of the model as substrate exhaustion was approached. Such rate constants may in the future find utility for describing and comparing cellulose fermentation involving other microbes and other substrates. Copyright © 2013 Wiley Periodicals, Inc.

  8. Time-dependent radiation characteristics of Nannochloropsis oculata during batch culture

    International Nuclear Information System (INIS)

    Heng, Ri-Liang; Pilon, Laurent

    2014-01-01

    This paper reports the temporal evolution of the scattering and absorbing cross-sections of marine eustigmatophycease Nannochloropsis oculata grown in a flat-plate photobioreactor (PBR). The PBR was operated in batch mode under constant irradiance of 7500 or 10,000 lux provided by red LEDs emitting at 630 nm. The radiation characteristics between 400 and 750 nm and pigment concentrations of N. oculata were measured systematically every 24 h for up to 18 days. They were found to vary significantly with time in response to changes in light and nutrients availability. The results were interpreted in terms of up- and down-regulations of pigments and other intracellular components. Finally, this study demonstrates that the light transfer in the PBR could be predicted using constant radiation characteristics measured during the exponential growth phase with reasonable accuracy provided that the cultures were not nitrogen limited. During nitrogen starvation, pigment concentrations decreased and radiation characteristics evolved rapidly. These results will be useful in the design and operation of PBRs for biofuel production at both small and large scales. - Highlights: • N. oculata cultures were grown in batch mode under two different irradiances. • Temporal evolution of their absorption and scattering cross-sections was reported. • The effects of photoacclimation and nitrogen starvation were quantified. • Results were interpreted in terms of regulation of cell constituents

  9. Continuous and batch cultures of Escherichia coli KJ134 for succinic acid fermentation: metabolic flux distributions and production characteristics.

    Science.gov (United States)

    van Heerden, Carel D; Nicol, Willie

    2013-09-17

    Succinic acid (SA) has become a prominent biobased platform chemical with global production quantities increasing annually. Numerous genetically modified E. coli strains have been developed with the main aim of increasing the SA yield of the organic carbon source. In this study, a promising SA-producing strain, E. coli KJ134 [Biotechnol. Bioeng. 101:881-893, 2008], from the Department of Microbiology and Cell Science of the University of Florida was evaluated under continuous and batch conditions using D-glucose and CO2 in a mineral salt medium. Production characteristics entailing growth and maintenance rates, growth termination points and metabolic flux distributions under growth and non-growth conditions were determined. The culture remained stable for weeks under continuous conditions. Under growth conditions the redox requirements of the reductive tricarboxylic acid (TCA) cycle was solely balanced by acetic acid (AcA) production via the pyruvate dehydrogenase route resulting in a molar ratio of SA:AcA of two. A maximum growth rate of 0.22 h(-1) was obtained, while complete growth inhibition occurred at a SA concentration of 18 g L(-1). Batch culture revealed that high-yield succinate production (via oxidative TCA or glyoxylate redox balancing) occurred under non-growth conditions where a SA:AcA molar ratio of up to five was attained, with a final SA yield of 0.94 g g(-1). Growth termination of the batch culture was in agreement with that of the continuous culture. The maximum maintenance production rate of SA under batch conditions was found to be 0.6 g g(-1) h(-1). This is twice the maintenance rate observed in the continuous runs. The study revealed that the metabolic flux of E. coli KJ134 differs significantly for growth and non-growth conditions, with non-growth conditions resulting in higher SA:AcA ratios and SA yields. Bioreaction characteristics entailing growth and maintenance rates, as well as growth termination markers will guide future fermentor

  10. Expression of a mutated SPT15 gene in Saccharomyces cerevisiae enhances both cell growth and ethanol production in microaerobic batch, fed-batch, and simultaneous saccharification and fermentations.

    Science.gov (United States)

    Seong, Yeong-Je; Park, Haeseong; Yang, Jungwoo; Kim, Soo-Jung; Choi, Wonja; Kim, Kyoung Heon; Park, Yong-Cheol

    2017-05-01

    The SPT15 gene encodes a Saccharomyces cerevisiae TATA-binding protein, which is able to globally control the transcription levels of various metabolic and regulatory genes. In this study, a SPT15 gene mutant (S42N, S78R, S163P, and I212N) was expressed in S. cerevisiae BY4741 (BSPT15-M3), of which effects on fermentative yeast properties were evaluated in a series of culture types. By applying different nitrogen sources and air supply conditions in batch culture, organic nitrogen sources and microaerobic condition were decided to be more favorable for both cell growth and ethanol production of the BSPT15-M3 strain than the control S. cerevisiae BY4741 strain expressing the SPT15 gene (BSPT15wt). Microaerobic fed-batch cultures of BSPT15-M3 with glucose shock in the presence of high ethanol content resulted in a 9.5-13.4% higher glucose consumption rate and ethanol productivity than those for the BSPT15wt strain. In addition, BSPT15-M3 showed 4.5 and 3.9% increases in ethanol productivity from cassava hydrolysates and corn starch in simultaneous saccharification and fermentation processes, respectively. It was concluded that overexpression of the mutated SPT15 gene would be a potent strategy to develop robust S. cerevisiae strains with enhanced cell growth and ethanol production abilities.

  11. Application of different feeding strategies in fed batch culture for pullulanase production using sago starch.

    Science.gov (United States)

    R, Shankar; M S, Madihah; E M, Shaza; K O, Nur Aswati; A A, Suraini; K, Kamarulzaman

    2014-02-15

    The production of pullulanase by Bacillus flavothermus KWF-1 in batch and fed batch culture were compared using 2L bioreactor. In batch culture, 0.0803 U/mL of pullulanase activity with specific activity of 0.0213 U/mg was produced by controlling the agitation speed and temperature at 200 rpm and 50 °C, respectively. Fed batch production was studied by feeding the culture with different sago starch concentrations in various feeding modes for enhanced pullulanase production. Exponential feeding mode at dilution rate of 0.01/h was the preeminent strategy for enhanced pullulanase production of 0.1710 U/mL with specific activity of 0.066 U/mg. It had shown an increment of pullulanase production and specific activity by 2.1 and 3.1-fold, respectively when compared to batch culture. Increment of pullulanase activity in exponential feeding mode improved hydrolyzation of sago starch into maltotriose and panose by 4.5 and 2.5-fold respectively compared to batch system. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Production of carotenoids and lipids by Rhodococcus opacus PD630 in batch and fed-batch culture.

    Science.gov (United States)

    Thanapimmetha, Anusith; Suwaleerat, Tharatron; Saisriyoot, Maythee; Chisti, Yusuf; Srinophakun, Penjit

    2017-01-01

    Production of carotenoids by Rhodococcus opacus PD630 is reported. A modified mineral salt medium formulated with glycerol as an inexpensive carbon source was used for the fermentation. Ammonium acetate was the nitrogen source. A dry cell mass concentration of nearly 5.4 g/L could be produced in shake flasks with a carotenoid concentration of 0.54 mg/L. In batch culture in a 5 L bioreactor, without pH control, the maximum dry biomass concentration was ~30 % lower than in shake flasks and the carotenoids concentration was 0.09 mg/L. Both the biomass concentration and the carotenoids concentration could be raised using a fed-batch operation with a feed mixture of ammonium acetate and acetic acid. With this strategy, the final biomass concentration was 8.2 g/L and the carotenoids concentration was 0.20 mg/L in a 10-day fermentation. A control of pH proved to be unnecessary for maximizing the production of carotenoids in this fermentation.

  13. ON-LINE MONITORING OF BIOMASS CONCENTRATION BASED ON A CAPACITANCE SENSOR: ASSESSING THE METHODOLOGY FOR DIFFERENT BACTERIA AND YEAST HIGH CELL DENSITY FED-BATCH CULTURES

    Directory of Open Access Journals (Sweden)

    A. C. L. Horta

    2015-12-01

    Full Text Available Abstract The performance of an in-situ capacitance sensor for on-line monitoring of biomass concentration was evaluated for some of the most important microorganisms in the biotechnology industry: Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris and Bacillus megaterium. A total of 33 batch and fed-batch cultures were carried out in a bench-scale bioreactor and biomass formation trends were followed by dielectric measurements during the growth phase as well as the induction phase, for 5 recombinant E. coli strains. Permittivity measurements and viable cellular concentrations presented a linear correlation for all the studied conditions. In addition, the permittivity signal was further used for inference of the cellular growth rate. The estimated specific growth rates mirrored the main trends of the metabolic states of the different cells and they can be further used for setting-up control strategies in fed-batch cultures.

  14. Improvement of xanthan gum production in batch culture using ...

    African Journals Online (AJOL)

    Yomi

    2011-12-21

    Dec 21, 2011 ... In this study, the effect of acetic acid on the improvement of xanthan biosynthesis by Xanthomonas campestris b82 was investigated. ... have been considered to improve xanthan productivity, which include improvement of culture ..... continuous production of xanthan gum. Paper presented at the Fifth.

  15. Medium optimization for protopectinase production by batch culture ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-11

    Nov 11, 2011 ... African Journal of Biotechnology Vol. ... protopectinase production were reported to be sucrose, yeast extracts and ammonium acetate by the ... influenced by medium compositions such as carbon sources, nitrogen sources, growth factors and inorganic salts. When compared with conventional method,.

  16. Improvement of xanthan gum production in batch culture using ...

    African Journals Online (AJOL)

    In this study, the effect of acetic acid on the improvement of xanthan biosynthesis by Xanthomonas campestris b82 was investigated. Various concentrations of acetic acid from 1.56 to 6.25 mM were added to the medium in the exponential and stationary phase of growth. Analytical studies revealed a considerable increase ...

  17. Studies of baby hamster kidney natural cell aggregation in suspended batch cultures.

    Science.gov (United States)

    Moreira, J L; Alves, P M; Rodrigues, J M; Cruz, P E; Aunins, J G; Carrondo, M J

    1994-11-30

    Microcarrier cultures of animal cells of industrial relevance are known to shed aggregates into the suspension phase. For a BHK cell line, which is known to be prone to aggregate naturally, microcarrier and aggregate forms of culture are compared in spinner culture. In microcarrier cultures, it is shown that increasing initial microcarrier concentration yields decreasing concentration of smaller aggregates in suspension; roughly equivalent concentrations of total cells and single cells in suspension are obtained. In the absence of Cytodex 3, aggregate final size is hydrodynamically controlled in batch and semicontinuous suspension culture. Rate of agitation is the main variable controlling aggregate size in batch cultures. The range of agitation rates studied (20 to 70 rpm in 250 mL spinner flasks) produced aggregates with maximum sizes of 200 microns. Necrotic centers were not observed; this was confirmed by Trypan blue viability measurements after mechanical dissociation of aggregates and also by the constant productivity obtained from different aggregate sizes. Comparing aggregate and microcarrier culture conditions, it is shown that at 100 rpm maximum total cell concentration is larger in the absence of microcarriers; dead cell concentrations, most of which exist in suspension, are slightly larger in microcarrier culture. Total viable cell concentrations in aggregate, hydrodynamically controlled culture, are almost one order of magnitude higher than in microcarrier cultures. These results suggest that there might be advantages in using aggregate cultures under hydrodynamic control of aggregate size in lieu of microcarrier cultures for naturally aggregating cell lines.

  18. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation.

    Science.gov (United States)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian; Wagtberg Sen, Jette; Rasmussen, Søren Kofoed; Kontoravdi, Cleo; Weilguny, Dietmar; Andersen, Mikael Rørdam

    2015-03-01

    Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process optimization, especially media optimization. Gaining knowledge on their interrelations could provide insight for obtaining higher immunoglobulin G (IgG) titer and better controlling glycosylation-related product quality. In this work, different fed-batch processes with two chemically defined proprietary media and feeds were studied using two IgG-producing cell lines. Our results indicate that the balance of glucose and amino acid concentration in the culture is important for cell growth, IgG titer and N-glycosylation. Accordingly, the ideal fate of glucose and amino acids in the culture could be mainly towards energy and recombinant product, respectively. Accumulation of by-products such as NH4(+) and lactate as a consequence of unbalanced nutrient supply to cell activities inhibits cell growth. The levels of Leu and Arg in the culture, which relate to cell growth and IgG productivity, need to be well controlled. Amino acids with the highest consumption rates correlate with the most abundant amino acids present in the produced IgG, and thus require sufficient availability during culture. Case-by-case analysis is necessary for understanding the effect of media and process optimization on glycosylation. We found that in certain cases the presence of Man5 glycan can be linked to limitation of UDP-GlcNAc biosynthesis as a result of insufficient extracellular Gln. However, under different culture conditions, high Man5 levels can also result from low α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase (GnTI) and UDP-GlcNAc transporter activities, which may be attributed to high level of NH4+ in the cell culture. Furthermore, galactosylation of the mAb Fc glycans

  19. Fed-batch CHO cell culture for lab-scale antibody production

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Ley, Daniel; Andersen, Mikael Rørdam

    2017-01-01

    Fed-batch culture is the most commonly used upstream process in industry today for recombinant monoclonal antibody production using Chinese hamster ovary cells. Developing and optimizing this process in the lab is crucial for establishing process knowledge, which enable rapid and predictable tech...

  20. Selection of chemically defined media for CHO cell fed-batch culture processes

    NARCIS (Netherlands)

    Pan, X.; Streefland, M.; Dalm, C.; Wijffels, R.H.; Martens, D.E.

    2017-01-01

    Two CHO cell clones derived from the same parental CHOBC cell line and producing the same monoclonal antibody (BC-G, a low producing clone; BC-P, a high producing clone) were tested in four basal media in all possible combinations with three feeds (=12 conditions) in fed-batch cultures.
    Higher

  1. Cultural Globalization and Economic Growth

    Directory of Open Access Journals (Sweden)

    Nuno Carlos Leitão

    2013-03-01

    Full Text Available This article investigates the relationship between cultural globalization and economic growth for the Portuguese experience for the period 1995-2011. In this research we apply a static and dynamic panel data. The initial GDP per capita is negatively correlated with economic growth. This result is according to theoretical and empirical studies. This paper shows that international trade and cultural globalization promote the economic growth. As we expected the inflation has a negative impact on economic growth.

  2. Crescimento e composição química de dez espécies de microalgas marinhas em cultivos estanques Growth and chemical composition of ten species of marine microalgae in batch cultures

    Directory of Open Access Journals (Sweden)

    Viviane Borges-Campos

    2010-02-01

    Full Text Available Microalgas apresentam diversas aplicações econômicas consagradas, como usos na aquicultura e na indústria de alimentos, havendo buscas por novos usos, como a geração de biomassa para produção de biodiesel. As possíveis aplicações estão diretamente relacionadas à taxa de crescimento e ao perfil químico das espécies. Assim, a seleção de condições que promovam o aproveitamento da biomassa algácea é fundamental para sua utilização econômica. Neste estudo, 10 espécies de microalgas marinhas foram cultivadas e comparadas quanto ao crescimento e à composição química. Foram observadas diferenças na velocidade de crescimento, com espécies de células menores crescendo mais rapidamente que microalgas maiores. Teores de proteínas, carboidratos, lipídeos e pigmentos fotossintetizantes variaram amplamente entre as espécies, sendo as proteínas as substâncias mais abundantes. Todas as espécies apresentaram concentrações de ácidos aminados semelhantes, sendo os ácidos aspártico e glutâmico os mais abundantes. Algumas espécies apresentaram altas concentrações de ácidos graxos de importância econômica, como os ácidos eicosapentaenoico e linoleico. O balanço dos resultados indica que há poucas tendências gerais relacionadas a grandes grupos taxonômicos.Microalgae show several economic applications, such as uses in aquaculture and in food industry, and there is a search for new uses, such as the biomass production to convert into biodiesel. All possible applications are directly linked to growth rate and the chemical profile of the species. Thus, the selection of conditions to promote a better use of algal biomass is fundamental for economic purposes. In this study, 10 species of marine microalgae were cultured and compared for growth and chemical composition. Remarkable differences of growth performance have been observed, with species with small cell volumes growing faster than species with large cell volumes

  3. Changes of in vivo fluxes through central metabolic pathways during the production of nystatin by Streptomyces noursei in batch culture

    DEFF Research Database (Denmark)

    Jonsbu, E.; Christensen, Bjarke; Nielsen, Jens

    2001-01-01

    of the amino acids and calculated fluxes of the central metabolism showed that changes in the primary and secondary metabolisms occurred simultaneously. Changes in the profiles for the integrated fluxes showed a decreased flux through the pentose phosphate pathway and an increased flux in the tricarboxylic...... acid cycle relative to the glucose uptake rate when the culture entered a phase with reduced specific growth rate and enhanced nystatin yield. The flux through the pentose phosphate pathway seemed to be adjusted according to the NADPH requirement during the different phases of the batch fermentation....

  4. Benzoate-induced stress enhances xylitol yield in aerobic fed-batch culture of Candida mogii TISTR 5892.

    Science.gov (United States)

    Wannawilai, Siwaporn; Sirisansaneeyakul, Sarote; Chisti, Yusuf

    2015-01-20

    Production of the natural sweetener xylitol from xylose via the yeast Candida mogii TISTR 5892 was compared with and without the growth inhibitor sodium benzoate in the culture medium. Sodium benzoate proved to be an uncompetitive inhibitor in relatively poorly oxygenated shake flask aerobic cultures. In a better controlled aerobic environment of a bioreactor, the role of sodium benzoate could equally well be described as competitive, uncompetitive or noncompetitive inhibitor of growth. In intermittent fed-batch fermentations under highly aerobic conditions, the presence of sodium benzoate at 0.15gL(-1) clearly enhanced the xylitol titer relative to the control culture without the sodium benzoate. The final xylitol concentration and the average xylitol yield on xylose were nearly 50gL(-1) and 0.57gg(-1), respectively, in the presence of sodium benzoate. Both these values were substantially higher than reported for the same fermentation under microaerobic conditions. Therefore, a fed-batch aerobic fermentation in the presence of sodium benzoate is promising for xylitol production using C. mogii. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Time-dependent radiation characteristics of Nannochloropsis oculata during batch culture

    Science.gov (United States)

    Heng, Ri-Liang; Pilon, Laurent

    2014-09-01

    This paper reports the temporal evolution of the scattering and absorbing cross-sections of marine eustigmatophycease Nannochloropsis oculata grown in a flat-plate photobioreactor (PBR). The PBR was operated in batch mode under constant irradiance of 7500 or 10,000 lux provided by red LEDs emitting at 630 nm. The radiation characteristics between 400 and 750 nm and pigment concentrations of N. oculata were measured systematically every 24 h for up to 18 days. They were found to vary significantly with time in response to changes in light and nutrients availability. The results were interpreted in terms of up- and down-regulations of pigments and other intracellular components. Finally, this study demonstrates that the light transfer in the PBR could be predicted using constant radiation characteristics measured during the exponential growth phase with reasonable accuracy provided that the cultures were not nitrogen limited. During nitrogen starvation, pigment concentrations decreased and radiation characteristics evolved rapidly. These results will be useful in the design and operation of PBRs for biofuel production at both small and large scales.

  6. Multiple batch recharging for industrial CZ silicon growth

    Science.gov (United States)

    Fickett, B.; Mihalik, G.

    2001-05-01

    The Czochralski (CZ) crystal growth process used in the Siemens Solar Industries’ (SSI) Vancouver, WA facility was non-continuous. Each furnace run's production was limited by the size of the starting charge. Once the charge was depleted, the furnace was shut down, cooled, and set back up for the next run. A recharge system was developed which transforms standard CZ growth into a semi-continuous process. Now when the charge is depleted, the crucible can be refilled in situ as the grown ingot is being removed from the furnace. SSI has demonstrated up to 14 recharge cycles in a single run. The resulting benefits included: significant cost reduction, increased yield, increased throughput, reduced energy consumption, improved process capability, reduced material handling requirements, and reduced labor. The recharge system also enables the use of granular silicon, which requires less than 30% of the energy required when manufacturing silicon-starting materials. This significantly reduces the energy “pay-back” time associated with SSI's finished product, photovoltaic panels.

  7. Modeling kinetics of a large-scale fed-batch CHO cell culture by Markov chain Monte Carlo method.

    Science.gov (United States)

    Xing, Zizhuo; Bishop, Nikki; Leister, Kirk; Li, Zheng Jian

    2010-01-01

    Markov chain Monte Carlo (MCMC) method was applied to model kinetics of a fed-batch Chinese hamster ovary cell culture process in 5,000-L bioreactors. The kinetic model consists of six differential equations, which describe dynamics of viable cell density and concentrations of glucose, glutamine, ammonia, lactate, and the antibody fusion protein B1 (B1). The kinetic model has 18 parameters, six of which were calculated from the cell culture data, whereas the other 12 were estimated from a training data set that comprised of seven cell culture runs using a MCMC method. The model was confirmed in two validation data sets that represented a perturbation of the cell culture condition. The agreement between the predicted and measured values of both validation data sets may indicate high reliability of the model estimates. The kinetic model uniquely incorporated the ammonia removal and the exponential function of B1 protein concentration. The model indicated that ammonia and lactate play critical roles in cell growth and that low concentrations of glucose (0.17 mM) and glutamine (0.09 mM) in the cell culture medium may help reduce ammonia and lactate production. The model demonstrated that 83% of the glucose consumed was used for cell maintenance during the late phase of the cell cultures, whereas the maintenance coefficient for glutamine was negligible. Finally, the kinetic model suggests that it is critical for B1 production to sustain a high number of viable cells. The MCMC methodology may be a useful tool for modeling kinetics of a fed-batch mammalian cell culture process.

  8. Monitoring and robust adaptive control of fed-batch cultures of microorganisms exhibiting overflow metabolism [abstract

    Directory of Open Access Journals (Sweden)

    Vande Wouwer, A.

    2010-01-01

    Full Text Available Overflow metabolism characterizes cells strains that are likely to produce inhibiting by-products resulting from an excess of substrate feeding and a saturated respiratory capacity. The critical substrate level separating the two different metabolic pathways is generally not well defined. Monitoring of this kind of cultures, going from model identification to state estimation, is first discussed. Then, a review of control techniques which all aim at maximizing the cell productivity of fed-batch fermentations is presented. Two main adaptive control strategies, one using an estimation of the critical substrate level as set-point and another regulating the by-product concentration, are proposed. Finally, experimental investigations of an adaptive RST control scheme using the observer polynomial for the regulation of the ethanol concentration in Saccharomyces cerevisiae fed-batch cultures ranging from laboratory to industrial scales, are also presented.

  9. Production of Medium Chain Length Polyhydroxyalkanoates From Oleic Acid Using Pseudomonas putida PGA1 by Fed Batch Culture

    Directory of Open Access Journals (Sweden)

    Sidik Marsudi

    2010-10-01

    Full Text Available Bacterial polyhydroxyalkanoates (PHAs are a class of p0lymers currently receiving much attention because of their potential as renewable and biodegradable plastics. A wide variety of bacteria has been reported to produce PHAs including Pseudomonas strains. These strains are known as versatile medium chain length PHAs (PHAs-mcl producers using fatty acids as carbon source. Oleic acid was used to produce PHAs-mcl using Pseudomonas putida PGA 1 by continuous feeding of both nitrogen and carbon source, in a fed batch culture. During cell growth, PHAs also accumulated, indicating that PHA production in this organism is growth associated. Residual cell increased until the nitrogen source was depleted. At the end of fermentation, final cell concentration, PHA content, and roductivity were 30.2 g/L, 44.8 % of cell dry weight, and 0.188 g/l/h, respectively.

  10. A high-throughput media design approach for high performance mammalian fed-batch cultures.

    Science.gov (United States)

    Rouiller, Yolande; Périlleux, Arnaud; Collet, Natacha; Jordan, Martin; Stettler, Matthieu; Broly, Hervé

    2013-01-01

    An innovative high-throughput medium development method based on media blending was successfully used to improve the performance of a Chinese hamster ovary fed-batch medium in shaking 96-deepwell plates. Starting from a proprietary chemically-defined medium, 16 formulations testing 43 of 47 components at 3 different levels were designed. Media blending was performed following a custom-made mixture design of experiments considering binary blends, resulting in 376 different blends that were tested during both cell expansion and fed-batch production phases in one single experiment. Three approaches were chosen to provide the best output of the large amount of data obtained. A simple ranking of conditions was first used as a quick approach to select new formulations with promising features. Then, prediction of the best mixes was done to maximize both growth and titer using the Design Expert software. Finally, a multivariate analysis enabled identification of individual potential critical components for further optimization. Applying this high-throughput method on a fed-batch, rather than on a simple batch, process opens new perspectives for medium and feed development that enables identification of an optimized process in a short time frame.

  11. Batch Growth of Chlorella Vulgaris CCALA 896 versus Semi-Continuous Regimen for Enhancing Oil-Rich Biomass Productivity

    Directory of Open Access Journals (Sweden)

    Sigita Vaičiulytė

    2014-06-01

    Full Text Available The aim of this study was to induce lipid accumulation in Chlorella cells by creating stressful growth conditions. Chlorella vulgaris CCALA 896 was grown under various batch growth modes in basal and modified BG-11 and Kolkwitz culture broths, using a continuous light regimen of 150 µE/m2/s, at 30 °C. In order to perform the experiments, two indoor photobioreactor shapes were used: a cylindrical glass photobioreactor (CGPBR with a working volume of 350 mL, and a flat glass photobioreactor (FGPBR with a working volume of 550 mL. Stress-eliciting conditions, such as nitrogen and phosphorous starvation, were imposed in order to induce lipid accumulation. The results demonstrated that more than 56% of the lipids can be accumulated in Chlorella biomass grown under two-phase batch growth conditions. The highest biomass productivity of 0.30 g/L/d was obtained at the highest nominal dilution rate (0.167 day−1 during a semi-continuous regimen, using a modified Kolkwitz medium. During the pH-stress cycles, the amount of lipids did not increase significantly and a flocculation of Chlorella cells was noted.

  12. An evaluation of the accumulation of intracellular inorganic nitrogen pools by marine microalgae in batch cultures

    Directory of Open Access Journals (Sweden)

    Paris L. Lavín

    2005-06-01

    Full Text Available Methods of extraction, changes in concentrations with growth, and effects of culture conditions on intracellular inorganic nitrogen pools (IIN - ammonia, nitrite, and nitrate were studied in nine species of marine microalgae in batch cultures. The microalgae were analysed to compare three methods of extraction of IIN, one of them developed in this study. The extraction of IIN occurs efficient by with all three methods for four out of the nine species tested. However, for five species significant differences were found among the methods, the best results being obtained with the new method. Microalgae accumulate inorganic forms of nitrogen in different proportions. The species show higher concentrations of either ammonia or nitrate, and always lower concentrations of nitrite. Microalgae of smaller cellular volumes tend to attain higher values of IIN per cubic micrometer (the converse in large-volume species, with some exceptions (Amphidinium carterae and Nannochloropsis oculata. The use of aeration in the cultures determines a decrease in the concentrations of IIN, favours nitrogen assimilation, and generates an increase in growth rates and C:N ratio. High concentrations of IIN are characteristic of the exponential growth phase, but in some cases their occurrence may result from carbon deficiency.Métodos de extração, mudanças na concentração durante o crescimento e efeitos de condições de cultivo sobre conteúdos de nitrogênio inorgânico intracelular (NII - amônia, nitrito e nitrato foram estudados em nove espécies de microalgas marinhas em cultivos estanques. As microalgas foram analisadas para comparar três métodos de extração de NII, um dos quais desenvolvido neste estudo. A extração de NII ocorre de forma eficiente com os três métodos para quatro espécies. Contudo, para cinco espécies diferenças significativas foram encontradas e os melhores resultados foram obtidos com o método novo. As microalgas acumulam formas inorg

  13. Cell-controlled hybrid perfusion fed-batch CHO cell process provides significant productivity improvement over conventional fed-batch cultures.

    Science.gov (United States)

    Hiller, Gregory W; Ovalle, Ana Maria; Gagnon, Matthew P; Curran, Meredith L; Wang, Wenge

    2017-07-01

    A simple method originally designed to control lactate accumulation in fed-batch cultures of Chinese Hamster Ovary (CHO) cells has been modified and extended to allow cells in culture to control their own rate of perfusion to precisely deliver nutritional requirements. The method allows for very fast expansion of cells to high density while using a minimal volume of concentrated perfusion medium. When the short-duration cell-controlled perfusion is performed in the production bioreactor and is immediately followed by a conventional fed-batch culture using highly concentrated feeds, the overall productivity of the culture is approximately doubled when compared with a highly optimized state-of-the-art fed-batch process. The technology was applied with near uniform success to five CHO cell processes producing five different humanized monoclonal antibodies. The increases in productivity were due to the increases in sustained viable cell densities. Biotechnol. Bioeng. 2017;114: 1438-1447. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  14. Production of lactic acid from cheese whey by batch and repeated batch cultures of Lactobacillus sp. RKY2.

    Science.gov (United States)

    Kim, Hyang-Ok; Wee, Young-Jung; Kim, Jin-Nam; Yun, Jong-Sun; Ryu, Hwa-Won

    2006-01-01

    The fermentative production of lactic acid from cheese whey and corn steep liquor (CSL) as cheap raw materials was investigated by using Lactobacillus sp. RKY2 in order to develop a cost-effective fermentation medium. Lactic acid yields based on consumed lactose were obtained at more than 0.98 g/g from the medium containing whey lactose. Lactic acid productivities and yields obtained from whey lactose medium were slightly higher than those obtained from pure lactose medium. The lactic acid productivity gradually decreased with increase in substrate concentration owing to substrate and product inhibitions. The fermentation efficiencies were improved by the addition of more CSL to the medium. Moreover, through the cell-recycle repeated batch fermentation, lactic acid productivity was maximized to 6.34 g/L/h, which was 6.2 times higher than that of the batch fermentation.

  15. Cultural diversity and economic growth

    DEFF Research Database (Denmark)

    Ager, Philipp; Brückner, Markus

    2013-01-01

    We exploit the large inflow of immigrants to the US during the 1870–1920 period to examine the effects that within-county changes in the cultural composition of the US population had on output growth. We construct measures of fractionalization and polarization to distinguish between the different...

  16. O2 evolution and cyclic electron flow around photosystem I in long-term ground batch culture of Euglena gracilis

    Science.gov (United States)

    An, Yanjun; Wang, Suqin; Hao, Zongjie; Zhou, Yiyong; Liu, Yongding

    2014-12-01

    Based on the purpose of better exploring the function of green producers in the closed aquatic biological life support system, the condition of dynamic O2 evolution and performance of cyclic electron flow around photosystem I (CEF-PSI) in long-term ground batch culture of Euglena gracilis were studied, the relationship between linear electron flow (LEF) and CEF-PSI was revealed, the function of CEF-PSI was investigated. Excellent consistency in O2 evolution pattern was observed in cultures grown in both closed and open containers, O2 evolution was strictly suppressed in phase 1, but the rate of it increased significantly in phase 2. CEF-PSI was proposed to be active during the whole course of cultivation, even in the declining phase 3, it still operated at the extent of 47-55%. It is suggested that the relationship between LEF and CEF-PSI is not only competition but also reciprocity. CEF-PSI was proposed to contribute to the considerable growth in phase 1; it was also suggested to play an important protective role against photosystem II (PSII) photoinhibition at the greatly enhanced level (approximately 80-95%) on the 2nd day. Our results in this research suggest that E. gracilis had very particular photosynthetic characteristics, the strict O2 evolution suppression in the initial culture phase might be a special light acclimation behavior, and CEF-PSI could be an important mechanism involved in this kind of adaptation to the changeable light environment.

  17. Optimization of nutritional compositions of growth medium for Chlorella sp. FJ3 growth kinetics in batch and continuous-flow photoreactors.

    Science.gov (United States)

    Leu, Jyh-Yih; Lin, Yen-Hui

    2013-01-01

    This study investigates improvement to culture medium for specific growth rate of Chlorella sp. FJ3 using a fractional factorial design for 32 experiments with six variable components. Six tested components were NaNO3 (0.5 or 3.0 g/l), K2HPO4 (0.01 or 0.06 g/l), MgSO4 7H2O (0.05 or 1.0 g/l), CaCl2 x 2H2O (0.01 or 0.06 g/l), ferric ammonium citrate (0.002 or 0.02 g/l) and NaCl (0.5 or 5.0 g/l). Magnesium sulphate and interaction between magnesium sulphate and ferric ammonium citrate were found to be critical for the cultivation of Chlorella sp. FJ3. The optimal concentrations of MgSO4 x 7H2O and ferric ammonium citrate were found to be 2.0 and 0.35 g/l, respectively. The concentration of carbonate (CO3(2-)) in effluent confirmed that the optimized culture medium was associated with a high carbonate utilization rate and specific growth rate during a transient period in batch and continuous-flow tests. The extent of growth of strain FJ3 in the optimized medium was 1.61 times greater than that in a non-optimized medium in the batch test. In the continuous-flow test, the maximum growth of Chlorella strain FJ3 in the optimized medium was 1.77 times higher than that in a non-optimized medium. The rate of CO3(2-) fixation in the non-optimized and the optimized media was 339 mg/l-day and 887 mg/l-day, respectively, in the steady state. These experimental and modelling results indicated that optimization of concentration in nutritional compositions in the culture medium enhanced the capacity of Chlorella sp. FJ3 for inorganic carbon fixation in batch and continuous-flow modes of photoreactors.

  18. Time-Resolved Transcriptomics and Bioinformatic Analyses Reveal Intrinsic Stress Responses during Batch Culture of Bacillus subtilis

    NARCIS (Netherlands)

    Blom, Evert-Jan; Ridder, Anja N.J.A.; Lulko, Andrzej T.; Roerdink, Jos B.T.M.; Kuipers, Oscar P.

    2011-01-01

    We have determined the time-resolved transcriptome of the model gram-positive organism B. subtilis during growth in a batch fermentor on rich medium. DNA microarrays were used to monitor gene transcription using 10-minute intervals at 40 consecutive time points. From the growth curve and analysis of

  19. Cell-recycle batch process of Scheffersomyces stipitis and Saccharomyces cerevisiae co-culture for second generation bioethanol production.

    Science.gov (United States)

    Ashoor, Selim; Comitini, Francesca; Ciani, Maurizio

    2015-11-01

    To achieve an optimized co-culture ratio of Scheffersomyces stipitis and Saccharomyces cerevisiae for the production of second generation bioethanol under a cell-recycle batch process. Three Sacc. cerevisiae strains were evaluated in co-culture with Sch. stipitis CBS 5773 at different ratios using synthetic medium containing glucose and xylose. Bioreactor trials indicated that the optimal condition for ethanol production using Sacc. cerevisiae EC1118 and Sch. stipitis co-culture was 1 % of O2 concentration. To increase ethanol production with Sacc. cerevisiae/Sch. stipitis co-culture a cell-recycle batch process was evaluated. Using this process, the maximum ethanol production (9.73 g l(-1)) and ethanol yield (0.42 g g(-1)) were achieved exhibiting a tenfold increase in ethanol productivity in comparison with batch process (2.1 g l(-1) h(-1)). In these conditions a stabilization of the cells ratio Sacc. cerevisiae/Sch. stipitis (1:5) at steady state condition was obtained. Batch cells recycling fermentation is an effective process to use Sch. stipitis/Sacc. cerevisiae co-culture for second generation ethanol production.

  20. Concomitant reduction of lactate and ammonia accumulation in fed-batch cultures: Impact on glycoprotein production and quality.

    Science.gov (United States)

    Karengera, Eric; Robotham, Anna; Kelly, John; Durocher, Yves; De Crescenzo, Gregory; Henry, Olivier

    2018-01-05

    Lactate and ammonia accumulation is a major factor limiting the performance of fed-batch strategies for mammalian cell culture processes. In addition to the detrimental effects of these by-products on production yield, ammonia also contributes to recombinant glycoprotein quality deterioration. In this study, we tackled the accumulation of these two inhibiting metabolic wastes by culturing in glutamine-free fed-batch cultures an engineered HEK293 cell line displaying an improved central carbon metabolism. Batch cultures highlighted the ability of PYC2-overexpressing HEK293 cells to grow and sustain a relatively high viability in absence of glutamine without prior adaptation to the culture medium. In fed-batch cultures designed to maintain glucose at high concentration by daily feeding a glutamine-free concentrated nutrient feed, the maximum lactate and ammonia concentrations did not exceed 5 and 1 mM, respectively. In flask, this resulted in more than a 2.5-fold increase in IFNα2b titer in comparison to the control glutamine-supplied fed-batch. In bioreactor, this strategy led to similar reductions in lactate and ammonia accumulation and an increase in IFNα2b production. Of utmost importance, this strategy did not affect IFNα2b quality with respect to sialylation and glycoform distribution as confirmed by surface plasmon resonance biosensing and LC-MS, respectively. Our strategy thus offers an attractive and simple approach for the development of efficient cell culture processes for the mass production of high-quality therapeutic glycoproteins. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  1. A multi-pronged investigation into the effect of glucose starvation and culture duration on fed-batch CHO cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    In this study, omics-based analysis tools were used to explore the effect of glucose starvation and culture duration on monoclonal antibody (mAb) production in fed-batch CHO cell culture to gain better insight into how these parameters can be controlled to ensure optimal mAb productivity and qual...

  2. The distribution of phosphorus and its transformations during batch growth of Synechocystis.

    Science.gov (United States)

    Zhou, Yun; Nguyen, Binh T; Zhou, Chen; Straka, Levi; Lai, YenJung Sean; Xia, Siqing; Rittmann, Bruce E

    2017-10-01

    Phosphorus (P) is an essential nutrient that affects the growth and metabolism of microalgal biomass. Despite the obvious importance of P, the dynamics of how it is taken up and distributed in microalgae are largely undefined. In this study, we tracked the fate of P during batch growth of the cyanobacterium Synechocystis sp. PCC 6803. We determined the distribution of P in intracellular polymeric substances (IPS), extracellular polymeric substances (EPS), and soluble microbial products (SMP) for three initial ortho-phosphate concentrations. Results show that the initial P concentration had no impact on the production of biomass, SMP, and EPS. While the initial P concentration affected the rate and the timing of how P was transformed among internal and external forms of inorganic P (IP) and organic P (OP), the trends were the same no matter the starting P concentration. Initially, IP in the bulk solution was rapidly and simultaneously adsorbed by EPS (IP EPS ) and taken up as internal IP (IP int ). As the bulk-solution's IP was depleted, desorption of IP EPS became the predominant source for IP that was taken up by the growing cells and converted into OP int . At the end of the 9-d batch experiments, almost all P was OP, and most of the OP was intracellular. Based on all of the results, we propose a set of transformation pathways for P during the growth of Synechocystis. Key is that EPS and intracellular P pool play important and distinct roles in the uptake and storage of P. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Fuzzy control of ethanol concentration its application to maximum glutathione production in yeast fed-batch culture.

    Science.gov (United States)

    Alfafara, C G; Miura, K; Shimizu, H; Shioya, S; Suga, K; Suzuki, K

    1993-02-20

    A fuzzy logic controller (FLC) for the control of ethanol concentration was developed and utilized to realize the maximum production of glutathione (GSH) in yeast fedbatch culture. A conventional fuzzy controller, which uses the control error and its rate of change in the premise part of the linguistic rules, worked well when the initial error of ethanol concentration was small. However, when the initial error was large, controller overreaction resulted in an overshoot.An improved fuzzy controller was obtained to avoid controller overreaction by diagnostic determination of "glucose emergency states" (i.e., glucose accumulation or deficiency), and then appropriate emergency control action was obtained by the use of weight coefficients and modification of linguistic rules to decrease the overreaction of the controller when the fermentation was in the emergency state. The improved fuzzy controller was able to control a constant ethanol concentration under conditions of large initial error.The improved fuzzy control system was used in the GSH production phase of the optimal operation to indirectly control the specific growth rate mu to its critical value micro(c). In the GSH production phase of the fed-batch culture, the optimal solution was to control micro to micro(c) in order to maintain a maximum specific GSH production rate. The value of micro(c) also coincided with the critical specific growth rate at which no ethanol formation occurs. Therefore, the control of micro to micro(c) could be done indirectly by maintaining a constant ethanol concentration, that is, zero net ethanol formation, through proper manipulation of the glucose feed rate. Maximum production of GSH was realized using the developed FLC; maximum production was a consequence of the substrate feeding strategy and cysteine addition, and the FLC was a simple way to realize the strategy.

  4. Growth and recombinant protein expression with Escherichia coli in different batch cultivation media.

    Science.gov (United States)

    Hortsch, Ralf; Weuster-Botz, Dirk

    2011-04-01

    Parallel operated milliliter-scale stirred tank bioreactors were applied for recombinant protein expression studies in simple batch experiments without pH titration. An enzymatic glucose release system (EnBase), a complex medium, and the frequently used LB and TB media were compared with regard to growth of Escherichia coli and recombinant protein expression (alcohol dehydrogenase (ADH) from Lactobacillus brevis and formate dehydrogenase (FDH) from Candida boidinii). Dissolved oxygen and pH were recorded online, optical densities were measured at-line, and the activities of ADH and FDH were analyzed offline. Best growth was observed in a complex medium with maximum dry cell weight concentrations of 14 g L(-1). EnBase cultivations enabled final dry cell weight concentrations between 6 and 8 g L(-1). The pH remained nearly constant in EnBase cultivations due to the continuous glucose release, showing the usefulness of this glucose release system especially for pH-sensitive bioprocesses. Cell-specific enzyme activities varied considerably depending on the different media used. Maximum specific ADH activities were measured with the complex medium, 6 h after induction with IPTG, whereas the highest specific FDH activities were achieved with the EnBase medium at low glucose release profiles 24 h after induction. Hence, depending on the recombinant protein, different medium compositions, times for induction, and times for cell harvest have to be evaluated to achieve efficient expression of recombinant proteins in E. coli. A rapid experimental evaluation can easily be performed with parallel batch operated small-scale stirred tank bioreactors.

  5. Factors Involved in the In Vitro Fermentability of Short Carbohydrates in Static Faecal Batch Cultures

    Directory of Open Access Journals (Sweden)

    Eva Gietl

    2012-01-01

    Full Text Available In recent years, research has focused on the positive effects of prebiotics on intestinal health and gut microbiota. The relationship between their chemical structure and their fermentation pattern by human intestinal microbiota is still not well understood. The aim of this study was to improve understanding of this relationship and identify factors that may be used to design galactooligosaccharides that reach more distal regions than commercial prebiotics which mainly target the proximal colon. The following factors were investigated: monomer type, linkage, substitution, and degree of polymerisation. Total organic acid production from sugars by faecal bacteria was fitted to a model which allowed an estimate of the time when half of the maximal organic acid concentration was reached (T50 in static faecal batch cultures. The different factors can be grouped by their effectiveness at prolonging fermentation time as follows: substitution is most effective, with methylgalactose, β-galactose-pentaacetate, D-fucose, and galactitol fermented more slowly than D-galactose. Monomers and linkage also influence fermentation time, with L rhamnose, arabinose, melezitose, and xylose being fermented significantly slower than D-glucose (P<0.05, maltose, isomaltose, cellobiose, and gentiobiose showing that Glcα1-6Glc and Glcβ1-4Glc were utilised slowest. Chain length had the smallest effect on fermentation time.

  6. Fermentative hydrogen yields from different sugars by batch cultures of metabolically engineered Escherichia coli DJT135

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Dipankar; Hallenbeck, Patrick C. [Departement de Microbiologie et Immunologie, Universite de Montreal, CP 6128 succursale Centre-ville, Montreal, Quebec H3C 3J7 (Canada)

    2009-10-15

    Future sustainable production of biofuels will depend upon the ability to use complex substrates present in biomass if the use of simple sugars derived from food crops is to be avoided. Therefore, organisms capable of using a variety of fermentable carbon sources must be found or developed for processes that could produce hydrogen via fermentation. Here we have examined the ability of a metabolically engineered strain of Escherichia coli, DJT135, to produce hydrogen from glucose as well as various other carbon sources, including pentoses. The effects of pH, temperature and carbon source were investigated in batch experiments. Maximal hydrogen production from glucose was obtained at an initial pH of 6.5 and temperature of 35 C. Kinetic growth studies showed that the {mu}max was 0.0495 h{sup -1} with a Ks of 0.0274 g L{sup -1} when glucose was the sole carbon source in M9 (1X) minimal medium. Among the many sugar and sugar derivatives tested, hydrogen yields were highest with fructose, sorbitol and D-glucose; 1.27, 1.46 and 1.51 mol H{sub 2} mol{sup -1} substrate respectively. (author)

  7. Brunovsky Normal Form of Monod Kinetics Models and Growth Rate Control of a Fed-batch Cultivation Process

    Directory of Open Access Journals (Sweden)

    Pavlov Y.

    2007-12-01

    Full Text Available A mathematical methodology that gives assistance to design of fed-batch stabilization and control is presented. The methodology is based both on Utility theory and optimal Control theory. The Utility theory deals with the expressed subjective preferences and allows for the expert preferences to be taken in consideration in complex biotechnological systems as criteria for control and optimization. The Control theory is used for parameters stabilization of a fed-batch cultivation process. The control is written based on information of the growth rate. The simulations show good efficiency of the control laws.

  8. Monitoring and Characterization of Crystal Nucleation and Growth during Batch Crystallization

    NARCIS (Netherlands)

    Kadam, S.S.

    2012-01-01

    Batch crystallization is commonly used in pharmaceutical, agrochemical, specialty and fine chemicals industry. The advantages of batch crystallization lie in its ease of operation and the relatively simple equipment that can be used. On the other hand a major disadvantage associated with it is the

  9. Proteomic analysis of host cell protein dynamics in the supernatant of Fc-fusion protein-producing CHO DG44 and DUKX-B11 cell lines in batch and fed-batch cultures.

    Science.gov (United States)

    Park, Jin Hyoung; Jin, Jong Hwa; Ji, In Jung; An, Hyun Joo; Kim, Jong Won; Lee, Gyun Min

    2017-10-01

    Chinese hamster ovary (CHO) cells are the most widely used host cell lines for the commercial production of therapeutic proteins including Fc-fusion proteins. During the culture of recombinant CHO (rCHO) cells, host cell proteins (HCPs), secreted from viable cells and released from dead cells, accumulate extracellularly, potentially impairing product quality. In this study, the HCPs that accumulated extracellularly in batch and fed-batch cultures of Fc-fusion protein-producing rCHO cell lines (DG-Fc and DUKX-Fc) were identified and quantified using nanoflow liquid chromatography-tandem mass spectrometry (LC-MS/MS), followed by gene ontology and functional analysis. When the proteome database of Cricetulus griseus was used as a reference to identify the HCPs, more HCPs were identified for DG-Fc (1632 HCPs in batch culture and 1733 HCPs in fed-batch culture) than for DUKX-Fc (1114 HCPs in batch culture and 1002 HCPs in fed-batch culture). Clustering analysis of HCPs, which were classified into four clusters according to their concentration profiles during culture, showed that the concentration profiles of HCPs affecting the quality of Fc-fusion proteins correlated with changes in Fc-fusion protein quality. Taken together, the dataset of HCPs obtained in this study using the two different rCHO cell lines provides insights into the determination of appropriate target proteins to be removed during the culture and purification steps so as to ensure good Fc-fusion protein quality. Biotechnol. Bioeng. 2017;114: 2267-2278. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. High-cell-density fed-batch culture of Saccharomyces cerevisiae KV-25 using molasses and corn steep liquor.

    Science.gov (United States)

    Vu, Van Hanh; Kim, Keun

    2009-12-01

    High-cell-density cultivation of yeast was investigated using the agricultural waste products corn steep liquor (CSL) and molasses. The Saccharomyces cerevisiae KV-25 cell mass was significantly dependent on the ratio between C and N sources. The concentrations of molasses and CSL in the culture medium were statistically optimized at 10.25% (v/v) and 16.87% (v/v), respectively, by response surface methodology (RSM). Batch culture in a 5-l stirred tank reactor using the optimized medium resulted in a cell mass production of 36.5 g/l. In the fed-batch culture, the feed phase was preceded by a batch phase using the optimized medium, and a very high dried-cell-mass yield of 187.63 g/l was successfully attained by feeding a mixture of 20% (v/v) molasses and 80% (v/v) CSL at a rate of 22 ml/h. In this system, the production of cell mass depended mainly on the agitation speed, the composition of the feed medium, and the glucose level in the medium, but only slightly on the aeration rate.

  11. Characterization of nerolidol biotransformation based on indirect on-line estimation of biomass concentration and physiological state in batch cultures of Aspergillus niger.

    Science.gov (United States)

    Hrdlicka, Patrick J; Sørensen, Anders B; Poulsen, Bjarne R; Ruijter, George J G; Visser, Jaap; Iversen, Jens J L

    2004-01-01

    Biotransformation of the sesquiterpenoid trans-nerolidol by Aspergillus niger has previously been investigated as a method for the formation of 12-hydroxy-trans-nerolidol, a precursor in the synthesis of the industrially interesting flavor alpha-sinensal. We characterized biotransformations of cis-nerolidol, trans-nerolidol, and a commercially available cis/trans-nerolidol mixture in repeated batch cultures of A. niger grown in computer-controlled bioreactors. On-line quantification of titrant addition in pH control allowed characterization of (1) maximal specific growth rate in exponential growth phases, (2) exponential induction of acid formation in postexponential phases, (3) inhibition of organic acid formation after nerolidol addition, and (4) exponential recovery from this inhibition. Addition of a (+/-)-cis/trans-nerolidol mixture during exponential or postexponential phase to cultures grown in minimal medium at high dissolved oxygen tension (above 50% air saturation), to cultures at low dissolved oxygen tension (5% air saturation), or to cultures grown in rich medium demonstrated that the physiological state before nerolidol addition had a major influence on biotransformation. The maximal molar yield of 12-hydroxy-trans-nerolidol (9%) was obtained by addition of a (+/-)-cis/trans-nerolidol mixture to the culture in the postexponential phase at high dissolved oxygen tension in minimal medium. Similar yields were obtained in rich medium, where the rate of biotransformation was doubled.

  12. Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain▿

    Science.gov (United States)

    Zelle, Rintze M.; de Hulster, Erik; Kloezen, Wendy; Pronk, Jack T.; van Maris, Antonius J. A.

    2010-01-01

    A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter−1 of malate at a yield of 0.42 mol (mol glucose)−1 in calcium carbonate-buffered shake flask cultures. With shake flasks, process parameters that are important for scaling up this process cannot be controlled independently. In this study, growth and product formation by the engineered strain were studied in bioreactors in order to separately analyze the effects of pH, calcium, and carbon dioxide and oxygen availability. A near-neutral pH, which in shake flasks was achieved by adding CaCO3, was required for efficient C4 dicarboxylic acid production. Increased calcium concentrations, a side effect of CaCO3 dissolution, had a small positive effect on malate formation. Carbon dioxide enrichment of the sparging gas (up to 15% [vol/vol]) improved production of both malate and succinate. At higher concentrations, succinate titers further increased, reaching 0.29 mol (mol glucose)−1, whereas malate formation strongly decreased. Although fully aerobic conditions could be achieved, it was found that moderate oxygen limitation benefitted malate production. In conclusion, malic acid production with the engineered S. cerevisiae strain could be successfully transferred from shake flasks to 1-liter batch bioreactors by simultaneous optimization of four process parameters (pH and concentrations of CO2, calcium, and O2). Under optimized conditions, a malate yield of 0.48 ± 0.01 mol (mol glucose)−1 was obtained in bioreactors, a 19% increase over yields in shake flask experiments. PMID:20008165

  13. Novel approach of high cell density recombinant bioprocess development: Optimisation and scale-up from microlitre to pilot scales while maintaining the fed-batch cultivation mode of E. coli cultures

    Directory of Open Access Journals (Sweden)

    Rimšeliene Renata

    2010-05-01

    Full Text Available Abstract Background Bioprocess development of recombinant proteins is time consuming and laborious as many factors influence the accumulation of the product in the soluble and active form. Currently, in most cases the developmental line is characterised by a screening stage which is performed under batch conditions followed by the development of the fed-batch process. Performing the screening already under fed-batch conditions would limit the amount of work and guarantee that the selected favoured conditions also work in the production scale. Results Here, for the first time, high throughput multifactorial screening of a cloning library is combined with the fed-batch technique in 96-well plates, and a strategy is directly derived for scaling to bioreactor scale. At the example of a difficult to express protein, an RNase inhibitor, it is demonstrated that screening of various vector constructs and growth conditions can be performed in a coherent line by (i applying a vector library with promoters and ribosome binding sites of different strength and various fusion partners together with (ii an early stage use of the fed-batch technology. It is shown that the EnBase® technology provides an easy solution for controlled cultivation conditions in the microwell scale. Additionally the high cell densities obtained provide material for various analyses from the small culture volumes. Crucial factors for a high yield of the target protein in the actual case were (i the fusion partner, (ii the use of of a mineral salt medium together with the fed-batch technique, and (iii the preinduction growth rate. Finally, it is shown that the favorable conditions selected in the microwell plate and shake flask scales also work in the bioreactor. Conclusions Cultivation media and culture conditions have a major impact on the success of a screening procedure. Therefore the application of controlled cultivation conditions is pivotal. The consequent use of fed-batch

  14. Biomass and lipid production from Nannochloropsis oculata growth in raceway ponds operated in sequential batch mode under greenhouse conditions.

    Science.gov (United States)

    Millán-Oropeza, Aarón; Fernández-Linares, Luis

    2017-11-01

    The effect of sequential batch cultures of the marine microalgae Nannochloropsis oculata on lipid and biomass production was studied in 200-L raceway ponds for 167 days (nine harvesting cycles) during winter and spring seasons under greenhouse conditions. The highest biomass concentration and productivity were 1.2 g/L and 49.8 mg/L/day on days 73 (5th cycle) and 167 (9th cycle), respectively. The overall interval of lipid production was between 131 and 530 mg/L. Despite the daily and seasonal variations of light irradiance (0-1099 μmol photon/m 2  s), greenhouse temperature (2.1-50.7 °C), and culture temperature (12.5-31.4 °C), ANOVA analysis showed no statistical difference (p value > 0.01) on the fatty acid methyl ester (FAMES) composition over the nine harvesting cycles evaluated. The most abundant FAMES were palmitic (C16:0), stearic (C18:0) and palmitoleic (C16:1∆9) acids with 37.1, 28.6, and 8.4 %, respectively. The sequential batch cultures of N. oculata in raceway ponds showed an increasing biomass production in each new cycle while keeping the quality of the fatty acid mixture under daily and seasonal variations of light irradiance and temperature.

  15. Fed-batch strategy for enhancing cell growth and C-phycocyanin production of Arthrospira (Spirulina) platensis under phototrophic cultivation.

    Science.gov (United States)

    Xie, Youping; Jin, Yiwen; Zeng, Xianhai; Chen, Jianfeng; Lu, Yinghua; Jing, Keju

    2015-03-01

    The C-phycocyanin generated in blue-green algae Arthrospira platensis is gaining commercial interest due to its nutrition and healthcare value. In this study, the light intensity and initial biomass concentration were manipulated to improve cell growth and C-phycocyanin production of A.platensis in batch cultivation. The results show that low light intensity and high initial biomass concentration led to increased C-phycocyanin accumulation. The best C-phycocyanin productivity occurred when light intensity and initial biomass concentration were 300μmol/m(2)/s and 0.24g/L, respectively. The fed-batch cultivation proved to be an effective strategy to further enhance C-phycocyanin production of A.platensis. The results indicate that C-phycocyanin accumulation not only requires nitrogen-sufficient condition, but also needs other nutrients. The highest C-phycocyanin content (16.1%), production (1034mg/L) and productivity (94.8mg/L/d) were obtained when using fed-batch strategy with 5mM medium feeding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Kinetics of sugars consumption and ethanol inhibition in carob pulp fermentation by Saccharomyces cerevisiae in batch and fed-batch cultures.

    Science.gov (United States)

    Lima-Costa, Maria Emília; Tavares, Catarina; Raposo, Sara; Rodrigues, Brígida; Peinado, José M

    2012-05-01

    The waste materials from the carob processing industry are a potential resource for second-generation bioethanol production. These by-products are small carob kibbles with a high content of soluble sugars (45-50%). Batch and fed-batch Saccharomyces cerevisiae fermentations of high density sugar from carob pods were analyzed in terms of the kinetics of sugars consumption and ethanol inhibition. In all the batch runs, 90-95% of the total sugar was consumed and transformed into ethanol with a yield close to the theoretical maximum (0.47-0.50 g/g), and a final ethanol concentration of 100-110 g/l. In fed-batch runs, fresh carob extract was added when glucose had been consumed. This addition and the subsequent decrease of ethanol concentrations by dilution increased the final ethanol production up to 130 g/l. It seems that invertase activity and yeast tolerance to ethanol are the main factors to be controlled in carob fermentations. The efficiency of highly concentrated carob fermentation makes it a very promising process for use in a second-generation ethanol biorefinery.

  17. On-line monitoring of important organoleptic methyl-branched aldehydes during batch fermentation of starter culture Staphylococcus xylosus reveal new insight into their production in a model fermentation

    DEFF Research Database (Denmark)

    de Vos Petersen, Christian; Beck, Hans Christian; Lauritsen, Frants R

    2004-01-01

    of the very important flavor compounds 2-methylbutanal, 3-methylbutanal, and 2-methylpropanal with various growth conditions. We found that the aldehydes were present in the culture broth only as transient metabolites. They were produced in the exponential growth phase, reached a maximum concentration when......A small fermentor (55 mL) was directly interfaced to a membrane inlet mass spectrometer for continuous on-line monitoring of oxygen and volatile metabolites during batch fermentations of the starter culture Staphylococcus xylosus. Using this technique, we were able to correlate production...... the culture became anaerobic, and then they rapidly disappeared from the culture medium. This general pattern was observed for three different strains of S. xylosus and S. carnosus. Small amounts of inoculum or increased exposure to oxygen were found to favor production of the aldehydes as a result...

  18. Simulation and prediction of protein production in fed-batch E. coli cultures: An engineering approach.

    Science.gov (United States)

    Calleja, Daniel; Kavanagh, John; de Mas, Carles; López-Santín, Josep

    2016-04-01

    An overall model describing the dynamic behavior of fed-batch E. coli processes for protein production has been built, calibrated and validated. Using a macroscopic approach, the model consists of three interconnected blocks allowing simulation of biomass, inducer and protein concentration profiles with time. The model incorporates calculation of the extra and intracellular inducer concentration, as well as repressor-inducer dynamics leading to a successful prediction of the product concentration. The parameters of the model were estimated using experimental data of a rhamnulose-1-phosphate aldolase-producer strain, grown under a wide range of experimental conditions. After validation, the model has successfully predicted the behavior of different strains producing two different proteins: fructose-6-phosphate aldolase and ω-transaminase. In summary, the presented approach represents a powerful tool for E. coli production process simulation and control. © 2015 Wiley Periodicals, Inc.

  19. Short communication: A nanoemulsified form of oil blends positively affects the fatty acid proportion in ruminal batch cultures.

    Science.gov (United States)

    El-Sherbiny, M; Cieslak, A; Pers-Kamczyc, E; Szczechowiak, J; Kowalczyk, D; Szumacher-Strabel, M

    2016-01-01

    Two consecutive rumen batch cultures were used to study the effect of nanoemulsified oils as a new type of supplement, on the in vitro fatty acid proportion and vaccenic acid formation. Three levels (3, 5, and 7%) of 2 different oil blends [soybean:fish oil (SF) or rapeseed-fish oil (RF)] were used. Both oil blends were used either in the raw form (SF or RF, respectively) or in the nanoemulsified form (NSF or NRF, respectively). The diets were the control (0%), which consisted of a dry total mixed ration without any supplements, the control plus 3, 5, or 7% of the SF or RF oil blend in appropriate form (raw or nanoemulsified). For each treatment, 6 incubation vessels were used. Each batch culture was incubated for 24h and conducted twice in 2 consecutive days. All supplements were calculated as a percentage of the substrate dry matter (400mg). Nanoemulsified supplements were recalculated to make sure the oil amount was equal to the raw oil supplementation levels. The results from both experiments indicated that the proportions of vaccenic acid and cis-9,trans-11 C18:2 increased when a raw oil blend was supplemented; on the other hand, no influence of nanoemulsified form of oil blend was observed on the proportion cis-9,trans-11 C18:2. Generally, supplementation with the nanoemulsified oil blends had less effect on biohydrogenation intermediates than the raw form of oil blends. However, the nanoemulsified form had a greater effect on the increase of n-3 and n-6 fatty acids. Nanoemulsified oil blends had a positive effect on decreasing the transformation rate of polyunsaturated fatty acids to saturated fatty acids in the biohydrogenation environment. Supplements of nanoemulsified oil blends tended to be more effective than supplements of raw oils in preserving a greater proportion of polyunsaturated fatty acids in the fermentation culture. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. In vitro batch cultures of gut microbiota from healthy and ulcerative colitis (UC) subjects suggest that sulphate-reducing bacteria levels are raised in UC and by a protein-rich diet.

    Science.gov (United States)

    Khalil, Nazeha A; Walton, Gemma E; Gibson, Glenn R; Tuohy, Kieran M; Andrews, Simon C

    2014-02-01

    Imbalances in gut microbiota composition during ulcerative colitis (UC) indicate a role for the microbiota in propagating the disorder. Such effects were investigated using in vitro batch cultures (with/without mucin, peptone or starch) inoculated with faecal slurries from healthy or UC patients; the growth of five bacterial groups was monitored along with short-chain fatty acid (SCFA) production. Healthy cultures gave two-fold higher growth and SCFA levels with up to ten-fold higher butyrate production. Starch gave the highest growth and SCFA production (particularly butyrate), indicating starch-enhanced saccharolytic activity. Sulphate-reducing bacteria (SRB) were the predominant bacterial group (of five examined) for UC inocula whereas they were the minority group for the healthy inocula. Furthermore, SRB growth was stimulated by peptone presumably due to the presence of sulphur-rich amino acids. The results suggest raised SRB levels in UC, which could contribute to the condition through release of toxic sulphide.

  1. Development of a chemically defined platform fed-batch culture media for monoclonal antibody-producing CHO cell lines with optimized choline content.

    Science.gov (United States)

    Kuwae, Shinobu; Miyakawa, Ichiko; Doi, Tomohiro

    2018-01-11

    A chemically defined platform basal medium and feed media were developed using a single Chinese hamster ovary (CHO) cell line that produces a monoclonal antibody (mAb). Cell line A, which showed a peak viable cell density of 5.9 × 10 6  cells/mL and a final mAb titer of 0.5 g/L in batch culture, was selected for the platform media development. Stoichiometrically balanced feed media were developed using glucose as an indicator of cell metabolism to determine the feed rates of all other nutrients. A fed-batch culture of cell line A using the platform fed-batch medium yielded a 6.4 g/L mAb titer, which was 12-fold higher than that of the batch culture. To examine the applicability of the platform basal medium and feed media, three other cell lines (A16, B, and C) that produce mAbs were cultured using the platform fed-batch medium, and they yielded mAb titers of 8.4, 3.3, and 6.2 g/L, respectively. The peak viable cell densities of the three cell lines ranged from 1.3 × 10 7 to 1.8 × 10 7  cells/mL. These results show that the nutritionally balanced fed-batch medium and feeds worked well for other cell lines. During the medium development, we found that choline limitation caused a lower cell viability, a lower mAb titer, a higher mAb aggregate content, and a higher mannose-5 content. The optimal choline chloride to glucose ratio for the CHO cell fed-batch culture was determined. Our platform basal medium and feed media will shorten the medium-development time for mAb-producing cell lines.

  2. Autotrophic growth and lipid production of Chlorella sorokiniana in lab batch and BIOCOIL photobioreactors: Experiments and modeling.

    Science.gov (United States)

    Concas, Alessandro; Malavasi, Veronica; Costelli, Cristina; Fadda, Paolo; Pisu, Massimo; Cao, Giacomo

    2016-07-01

    A novel mathematical model for the quantitative assessment of the effect of dissolved nitrogen on the autotrophic batch-growth and lipid accumulation of Chlorella sorokiniana, is proposed in this work. Model results have been validated through comparison with suitable experimental data performed in lab photobioreactors. Further experiments have been then performed using the BIOCOIL photobioreactor operated in fed-batch mode. The experimental results, which show that a maximum growth rate of 0.52day(-1) and a lipid content equal to 25%wt can be achieved with the BIOICOIL, have been successfully predicted through the proposed model. Therefore, the model might represent a first step toward the development of a tool for the scale-up and optimization of the operating conditions of BIOCOIL photobioreactors. Finally, the fatty acid methyl esters obtained by trans-esterification of lipids extracted from C. sorokiniana, have been analyzed in view of the assessment of their usability for producing biodiesel. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Stochastic modelling of Listeria monocytogenes single cell growth in cottage cheese with mesophilic lactic acid bacteria from aroma producing cultures

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Christiansen, Lasse Engbo; Dalgaard, Paw

    2015-01-01

    . 2014. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese. International Journal of Food Microbiology. 188, 15-25]. Growth of L. monocytogenes single cells, using lag time distributions corresponding to three different......A stochastic model was developed for simultaneous growth of low numbers of Listeria monocytogenes and populations of lactic acid bacteria from the aroma producing cultures applied in cottage cheese. During more than two years, different batches of cottage cheese with aroma culture were analysed...

  4. Enhancement of fermentative hydrogen production in an extreme-thermophilic (70°C) mixed-culture environment by repeated batch cultivation.

    Science.gov (United States)

    Lu, Wenjing; Fan, Gaoyuan; Zhao, Chenxi; Wang, Hongtao; Chi, Zifang

    2012-05-01

    Repeated batch cultivation was applied to enrich hydrogen fermentative microflora under extreme-thermophilic (70°C) environment. Initial inoculums received from a hydrogen producing reactor fed with organic fraction of household solid wastes. In total seven transfers was conducted and maximum hydrogen yield reached 296 ml H(2)/g (2.38 mol/mol) glucose and 252 ml H(2)/g (2.03 mol/mol) for 1 and 2 g/l glucose medium, respectively. It was found that hydrogen production was firstly decreased and got increased gradually from third generation. Acetate was found to be the main metabolic by-product in all batch cultivation. Furthermore, the diversity of bacterial community got decreased after repeated batch cultivation. It was proved that repeated batch cultivation was a good method to enhance the hydrogen production by enriching the mixed cultures of dominant species.

  5. Optimum CFST (continuous flow stirred tank) bioreactor design: Experimental study using batch growth parameters for Saccharomyces cerevisiae producing ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Wall, J.B.; Hill, G.A. (Saskatchewan Univ., Saskatoon, SK (Canada))

    1992-02-01

    An optimum continuous flow stirred-tank (CFST) bioreactor design equation is presented which can be used with linear growth-associated product inhibition models. Batch experiments were performed to determine Saccharomyces cerevisiae growth parameters required for solving the optimum design equation. The three bioreactors were designed in decreasing volumes to achieve theoretical glucose conversions of 99.9% and 99.99%. At steady state, the bioreactors appeared to reach the theoretical conditions as long as the flowrates were held equal or slightly below the optimum conditions. At very low flowrates, biomass death was observed in down-stream reactors while at high flowrates, the theoretical conversions were not achieved. The experimental results confirm that optimally designed bioreactors can offer lower processing volumes to achieve high substrate conversions as compared to single CFST bioreactors. 9 refs., 8 figs., 1 tab.

  6. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    Energy Technology Data Exchange (ETDEWEB)

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  7. Pilot-Scale Lactic Acid Production via Batch Culturing of Lactobacillus sp. RKY2 Using Corn Steep Liquor As a Nitrogen Source

    Directory of Open Access Journals (Sweden)

    Young-Jung Wee

    2006-01-01

    Full Text Available In this study, the determination of the efficiency of a pilot-scale fermentation process using corn steep liquor as a nitrogen source was attempted in order to produce lactic acid via batch culturing of Lactobacillus sp. RKY2. Using pure glucose, fermentation efficiency characteristics, such as final lactic acid, cell growth, yield, and productivity were not substantially influenced by the scale-up of the laboratory-scale fermentation from 2.5- to 30- and 300-litre scale fermentations. In all experiments, the content of lactic acid produced increased in a linear fashion with increases in the initial glucose concentration. In the experiments using wood hydrolyzate, both lactic acid productivity and cell growth were decreased as a result of the scaling-up of the fermentation. This might be attributed to the toxic chemicals contained in the wood hydrolyzates. However, in all experiments, lactic acid yields remained higher than 90 % with regard to the amount of glucose consumed. Therefore, lactic acid was successfully produced by the pilot-scale bioreactor scheme adopted in this study.

  8. Changes In Growth Culture FDA Activity Under Changing Growth Conditions

    DEFF Research Database (Denmark)

    Jørgensen, Per Elberg; Eriksen, Thomas Juul; Jensen, Bjørn K.

    1992-01-01

    of the bacteria. The FDA activity/ATP ratio was calculated for different concentrations of autoclaved sludge. A faster decay rate of ATP relative to FDA hydrolysis activity was observed, thus causing changes in the ratio. Furthermore, comparison between values obtained from pure cultures and different soils......The FDA hydrolysis capacities and bacterial biomass concentrations (estimated by determination of ATP content) of growth cultures prepared from activated sludge and wastewater, were measured to find out whether the FDA activity would reflect bacterial biomass under different physiological states...

  9. Evidencing the role of lactose permease in IPTG uptake by Escherichia coli in fed-batch high cell density cultures.

    Science.gov (United States)

    Fernández-Castané, Alfred; Vine, Claire E; Caminal, Glòria; López-Santín, Josep

    2012-02-10

    The lac-operon and its components have been studied for decades and it is widely used as one of the common systems for recombinant protein production in Escherichia coli. However, the role of the lactose permease, encoded by the lacY gene, when using the gratuitous inducer IPTG for the overexpression of heterologous proteins, is still a matter of discussion. A lactose permease deficient strain was successfully constructed. Growing profiles and acetate production were compared with its parent strain at shake flask scale. Our results show that the lac-permease deficient strain grows slower than the parent in defined medium at shake flask scale, probably due to a downregulation of the phosphotransferase system (PTS). The distributions of IPTG in the medium and inside the cells, as well as recombinant protein production were measured by HPLC-MS and compared in substrate limiting fed-batch fermentations at different inducer concentrations. For the mutant strain, IPTG concentration in the medium depletes slower, reaching at the end of the culture higher concentration values compared with the parent strain. Final intracellular and medium concentrations of IPTG were similar for the mutant strain, while higher intracellular concentrations than in medium were found for the parent strain. Comparison of the distribution profiles of IPTG of both strains in fed-batch fermentations showed that lac-permease is crucially involved in IPTG uptake. In the absence of the transporter, apparently IPTG only diffuses, while in the presence of lac-permease, the inducer accumulates in the cytoplasm at higher rates emphasizing the significant contribution of the permease-mediated transport. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Enhancement of extracellular lipid production by oleaginous yeast through preculture and sequencing batch culture strategy with acetic acid.

    Science.gov (United States)

    Huang, Xiang-Feng; Shen, Yi; Luo, Hui-Juan; Liu, Jia-Nan; Liu, Jia

    2018-01-01

    Oleaginous yeast Cryptococcus curvatus MUCL 29819, an acid-tolerant lipid producer, was tested to spill lipids extracellularly using different concentrations of acetic acid as carbon source. Extracellular lipids were released when the yeast was cultured with acetic acid exceeding 20g/L. The highest production of lipid (5.01g/L) was obtained when the yeast was cultured with 40g/L acetic acid. When the yeast was cultivated with moderate concentration (20g/L) of acetic acid, lipid production was further increased by 49.6% through preculture with 40g/L acetic acid as stimulant. When applying high concentration (40g/L) of acetic acid as carbon source in sequencing batch cultivation, extracellular lipids accounted up to 50.5% in the last cycle and the extracellular lipids reached 5.43g/L through the whole process. This study provides an effective strategy to enhance extracellular lipid production and facilitate the recovery of microbial lipids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. An absolute procedure to test the growth potential of medium and the influence of decreased oxygen tension in primary amniotic fluid cell cultures

    NARCIS (Netherlands)

    Sikkema-Raddatz, Birgit; Suijkerbuijk, Ron; van der Vlag, Jakob; Stoepker, Marian; Buys, Charles H. C. M.; Meerman, Gerard J. te

    Objective For prenatal cytogenetic diagnosis, cell cultures should be maximally successful. When introducing a change in conditions, e.g. a new batch of medium, the growth potential of a culture is usually compared under both the new condition and the one already in use. Such a relative test is in

  12. An absolute procedure to test the growth potential of medium and the influence of decreased oxygen tension in primary amniotic fluid cell cultures.

    NARCIS (Netherlands)

    Sikkema-Raddatz, B.; Suijkerbuijk, R.F.; Vlag, J. van der; Stoepker, M.; Buys, C.H.C.M.; Meerman, G.J. te

    2006-01-01

    OBJECTIVE: For prenatal cytogenetic diagnosis, cell cultures should be maximally successful. When introducing a change in conditions, e.g. a new batch of medium, the growth potential of a culture is usually compared under both the new condition and the one already in use. Such a relative test is in

  13. A new bioenergetic and thermodynamic approach to batch photoautotrophic growth of Arthrospira (Spirulina) platensis in different photobioreactors and under different light conditions.

    Science.gov (United States)

    da Silva, Milena Fernandes; Casazza, Alessandro Alberto; Ferrari, Pier Francesco; Perego, Patrizia; Bezerra, Raquel Pedrosa; Converti, Attilio; Porto, Ana Lucia Figueiredo

    2016-05-01

    Photobioreactor configuration, mode of operation and light intensity are known to strongly impact on cyanobacteria growth. To shed light on these issues, kinetic, bioenergetic and thermodynamic parameters of batch Arthrospira platensis cultures were estimated along the time at photosynthetic photon flux density (PPFD) of 70μmolm(-2)s(-1) in different photobioreactors with different surface/volume ratio (S/V), namely open pond (0.25cm(-1)), shaken flask (0.48cm(-1)), horizontal photobioreactor (HoP) (1.94cm(-1)) and helicoidal photobioreactor (HeP) (3.88cm(-1)). Maximum biomass concentration and productivity remarkably increased with S/V up to 1.94cm(-1). HoP was shown to be the best-performing system throughout the whole runs, while HeP behaved better only at the start. Runs carried out in HoP increasing PPFD from 40 to 100μmolm(-2)s(-1) revealed a progressive enhancement of bioenergetics and thermodynamics likely because of favorable light distribution. HoP appeared to be a promising configuration to perform high-yield indoor cyanobacterial cultures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Production of functional killer protein in batch cultures upon a shift from aerobic to anaerobic conditions

    Directory of Open Access Journals (Sweden)

    Gildo Almeida da Silva

    2011-06-01

    Full Text Available The aim of this work was to study the production of functional protein in yeast culture. The cells of Saccharomyces cerevisiae Embrapa 1B (K+R+ killed a strain of Saccharomyces cerevisiae Embrapa 26B (K-R-in grape must and YEPD media. The lethal effect of toxin-containing supernatant and the effect of aeration upon functional killer production and the correlation between the products of anaerobic metabolism and the functional toxin formation were evaluated. The results showed that at low sugar concentration, the toxin of the killer strain of Sacch. cerevisiae was only produced under anaerobic conditions . The system of killer protein production showed to be regulated by Pasteur and Crabtree effects. As soon as the ethanol was formed, the functional killer toxin was produced. The synthesis of the active killer toxin seemed to be somewhat associated with the switch to fermentation process and with concomitant alcohol dehydrogenase (ADH activity.

  15. Growth and exopolysaccharide yield of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081 in batch and continuous bioreactor experiments at constant pH.

    Science.gov (United States)

    Mende, Susann; Krzyzanowski, Leona; Weber, Jost; Jaros, Doris; Rohm, Harald

    2012-02-01

    Some Lactobacillus delbrueckii ssp. bulgaricus strains are able to synthesize exopolysaccharides (EPS) and are therefore highly important for the dairy industry as starter cultures. The aim of this study was to investigate the nutritional requirements for growth and EPS production of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081. A medium was developed from a semi-defined medium (SDM) in which glucose was replaced by lactose and different combinations of supplements (nucleobases, vitamins, salts, sodium formate and orotic acid) were added. Constant pH batch fermentation with the modified medium resulted in an EPS yield of approximately 210 mg glucose equivalents per liter medium. This was a 10-fold increase over flask cultivation of this strain in SDM. Although not affecting cell growth, the mixture of salts enhanced the EPS synthesis. Whereas EPS production was approximately 12 mg/g dry biomass without salt supplementation, a significantly higher yield (approximately 20 mg/g dry biomass) was observed after adding the salt mixture. In continuous fermentation, a maximal EPS concentration was obtained at a dilution rate of 0.31/h (80 mg EPS/L), which corresponded to a specific EPS production of 49 mg/g dry biomass. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  16. Modelling of Batch Process Operations

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli; Cameron, Ian; Gani, Rafiqul

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  17. GROWTH AND COMPOSITION OF Arthrospira (Spirulina platensis IN A TUBULAR PHOTOBIOREACTOR USING AMMONIUM NITRATE AS THE NITROGEN SOURCE IN A FED-BATCH PROCESS

    Directory of Open Access Journals (Sweden)

    C. Cruz-Martínez

    2015-06-01

    Full Text Available AbstractNH4NO3 simultaneously provides a readily assimilable nitrogen source (ammonia and a reserve of nitrogen (nitrate, allowing for an increase in Arthrospira platensis biomass production while reducing the cost of the cultivation medium. In this study, a 22plus star central composite experimental design combined with response surface methodology was employed to analyze the influence of light intensity (I and the total amount of added NH4NO3 (Mt on a bench-scale tubular photobioreactor for fed-batch cultures. The maximum cell concentration (Xm, cell productivity (PX and biomass yield on nitrogen (YX/N were evaluated, as were the protein and lipid contents. Under optimized conditions (I = 148 μmol·photons·m-2·s-1 and Mt = 9.7 mM NH4NO3, Xm = 4710 ±34.4 mg·L-1, PX = 478.9 ±3.8 mg·L-1·d-1 and YX/N = 15.87 ±0.13 mg·mg-1 were obtained. The best conditions for protein content in the biomass (63.2% were not the same as those that maximized cell growth (I = 180 μmol·photons·m-2·s-1 and Mt = 22.5 mM NH4NO3. Based on these results, it is possible to conclude that ammonium nitrate is an interesting alternate nitrogen source for the cultivation of A. platensisin a fed-batch process and could be used for other photosynthetic microorganisms.

  18. Population analysis of a commercial Saccharomyces cerevisiae wine yeast in a batch culture by electric particle analysis, light diffraction and flow cytometry.

    Science.gov (United States)

    Portell, Xavier; Ginovart, Marta; Carbo, Rosa; Gras, Anna; Vives-Rego, Josep

    2011-02-01

    Data from electric particle analysis, light diffraction and flow cytometry analysis provide information on changes in cell morphology. Here, we report analyses of Saccharomyces cerevisiae populations growing in a batch culture using these techniques. The size distributions were determined by electric particle analysis and by light diffraction in order to compare their outcomes. Flow cytometry parameters forward (related to cell size) and side (related to cell granularity) scatter were also determined to complement this information. These distributions of yeast properties were analysed statistically and by a complexity index. The cell size of Saccharomyces at the lag phase was smaller than that at the beginning of the exponential phase, whereas during the stationary phase, the cell size converged with the values observed during the lag phase. These experimental techniques, when used together, allow us to distinguish among and characterize the cell size, cell granularity and the structure of the yeast population through the three growth phases. Flow cytometry patterns are better than light diffraction and electric particle analysis in showing the existence of subpopulations during the different phases, especially during the stationary phase. The use of a complexity index in this context helped to differentiate these phases and confirmed the yeast cell heterogeneity. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  19. Genetic Algorithmic Optimization of PHB Production by a Mixed Culture in an Optimally Dispersed Fed-batch Bioreactor

    Directory of Open Access Journals (Sweden)

    Pratap R. Patnaik

    2009-10-01

    Full Text Available Poly-β-hydroxybutyrate (PHB is an energy-storage polymer whose properties are similar to those of chemical polymers such as polyethylene and polypropylene. Moreover, PHB is biodegradable, absorbed by human tissues and less energy-consuming than synthetic polymers. Although Ralstonia eutropha is widely used to synthesize PHB, it is inefficient in utilizing glucose and similar sugars. Therefore a co-culture of R. eutropha and Lactobacillus delbrueckii is preferred since the latter can convert glucose to lactate, which R. eutropha can metabolize easily. Tohyama et al. [24] maximized PHB production in a well-mixed fed-batch bioreactor with glucose and (NH42SO4 as the primary substrates. Since production-scale bioreactors often deviate from ideal laboratory-scale reactors, a large bioreactor was simulated by means of a dispersion model with the kinetics determined by Tohyama et al. [24] and dispersion set at an optimum Peclet number of 20 [32]. The time-dependent feed rates of the two substrates were determined through a genetic algorithm (GA to maximize PHB production. This bioreactor produced 22.2% more PHB per liter and 12.8% more cell mass than achieved by Tohyama et al. [24]. These results, and similar observations with other fermentations, indicate the feasibility of enhancing the efficiency of large nonideal bioreactors through GA optimizations.

  20. Calcium transcriptionally regulates the biofilm machinery of Xylella fastidiosa to promote continued biofilm development in batch cultures.

    Science.gov (United States)

    Parker, Jennifer K; Chen, Hongyu; McCarty, Sara E; Liu, Lawrence Y; De La Fuente, Leonardo

    2016-05-01

    The functions of calcium (Ca) in bacteria are less characterized than in eukaryotes, where its role has been studied extensively. The plant-pathogenic bacterium Xylella fastidiosa has several virulence features that are enhanced by increased Ca concentrations, including biofilm formation. However, the specific mechanisms driving modulation of this feature are unclear. Characterization of biofilm formation over time showed that 4 mM Ca supplementation produced denser biofilms that were still developing at 96 h, while biofilm in non-supplemented media had reached the dispersal stage by 72 h. To identify changes in global gene expression in X. fastidiosa grown in supplemental Ca, RNA-Seq of batch culture biofilm cells was conducted at three 24-h time intervals. Results indicate that a variety of genes are differentially expressed in response to Ca, including genes related to attachment, motility, exopolysaccharide synthesis, biofilm formation, peptidoglycan synthesis, regulatory functions, iron homeostasis, and phages. Collectively, results demonstrate that Ca supplementation induces a transcriptional response that promotes continued biofilm development, while biofilm cells in nonsupplemented media are driven towards dispersion of cells from the biofilm structure. These results have important implications for disease progression in planta, where xylem sap is the source of Ca and other nutrients for X. fastidiosa. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. Changes In Growth Culture FDA Activity Under Changing Growth Conditions

    DEFF Research Database (Denmark)

    Jørgensen, Per Elberg; Eriksen, Thomas Juul; Jensen, Bjørn K.

    1992-01-01

    The FDA hydrolysis capacities and bacterial biomass concentrations (estimated by determination of ATP content) of growth cultures prepared from activated sludge and wastewater, were measured to find out whether the FDA activity would reflect bacterial biomass under different physiological states...... of the bacteria. The FDA activity/ATP ratio was calculated for different concentrations of autoclaved sludge. A faster decay rate of ATP relative to FDA hydrolysis activity was observed, thus causing changes in the ratio. Furthermore, comparison between values obtained from pure cultures and different soils...... revealed differences up to two orders of magnitude of the ratio. Based on these results it was concluded that the FDA activity should not be applied for measurements of viable biomass in environments in which different physiological conditions occur....

  2. Impact of dilution on microbial community structure and functional potential: comparison of numerical simulations and batch culture experiments

    Science.gov (United States)

    Franklin, R. B.; Garland, J. L.; Bolster, C. H.; Mills, A. L.

    2001-01-01

    A series of microcosm experiments was performed using serial dilutions of a sewage microbial community to inoculate a set of batch cultures in sterile sewage. After inoculation, the dilution-defined communities were allowed to regrow for several days and a number of community attributes were measured in the regrown assemblages. Based upon a set of numerical simulations, community structure was expected to differ along the dilution gradient; the greatest differences in structure were anticipated between the undiluted-low-dilution communities and the communities regrown from the very dilute (more than 10(-4)) inocula. Furthermore, some differences were expected among the lower-dilution treatments (e.g., between undiluted and 10(-1)) depending upon the evenness of the original community. In general, each of the procedures used to examine the experimental community structures separated the communities into at least two, often three, distinct groups. The groupings were consistent with the simulated dilution of a mixture of organisms with a very uneven distribution. Significant differences in community structure were detected with genetic (amplified fragment length polymorphism and terminal restriction fragment length polymorphism), physiological (community level physiological profiling), and culture-based (colony morphology on R2A agar) measurements. Along with differences in community structure, differences in community size (acridine orange direct counting), composition (ratio of sewage medium counts to R2A counts, monitoring of each colony morphology across the treatments), and metabolic redundancy (i.e., generalist versus specialist) were also observed, suggesting that the differences in structure and diversity of communities maintained in the same environment can be manifested as differences in community organization and function.

  3. Polyhydroxybutyrate production by direct use of waste activated sludge in phosphorus-limited fed-batch culture.

    Science.gov (United States)

    Cavaillé, Laëtitia; Grousseau, Estelle; Pocquet, Mathieu; Lepeuple, Anne-Sophie; Uribelarrea, Jean-Louis; Hernandez-Raquet, Guillermina; Paul, Etienne

    2013-12-01

    Polyhydroxybutyrate (PHB) production directly by waste activated sludge (WAS) was investigated in aerobic fed-batch conditions using acetic acid as substrate. PHB production was induced by phosphorus limitation. WAS of different origin were tested with various degrees of phosphorus limitation and PHB contents of up to 70% (gCOD PHB/gCOD particulate) were obtained. This strategy showed the importance of maintaining cell growth for PHB production in order to increase PHB concentration and that the degree of phosphorus limitation has a direct impact on the quantity of PHB produced. Pyrosequencing of 16S rRNA transcripts showed changes in the active bacteria of the WAS microbial community as well as the acclimation of populations depending on sludge origin. The monitoring of the process appeared as the key factor for optimal PHB production by WAS. Different strategies are discussed and compared in terms of carbon yield and PHB content with the feast and famine selection process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Metabolic Control in Mammalian Fed-Batch Cell Cultures for Reduced Lactic Acid Accumulation and Improved Process Robustness.

    Science.gov (United States)

    Konakovsky, Viktor; Clemens, Christoph; Müller, Markus Michael; Bechmann, Jan; Berger, Martina; Schlatter, Stefan; Herwig, Christoph

    2016-01-11

    Biomass and cell-specific metabolic rates usually change dynamically over time, making the "feed according to need" strategy difficult to realize in a commercial fed-batch process. We here demonstrate a novel feeding strategy which is designed to hold a particular metabolic state in a fed-batch process by adaptive feeding in real time. The feed rate is calculated with a transferable biomass model based on capacitance, which changes the nutrient flow stoichiometrically in real time. A limited glucose environment was used to confine the cell in a particular metabolic state. In order to cope with uncertainty, two strategies were tested to change the adaptive feed rate and prevent starvation while in limitation: (i) inline pH and online glucose concentration measurement or (ii) inline pH alone, which was shown to be sufficient for the problem statement. In this contribution, we achieved metabolic control within a defined target range. The direct benefit was two-fold: the lactic acid profile was improved and pH could be kept stable. Multivariate Data Analysis (MVDA) has shown that pH influenced lactic acid production or consumption in historical data sets. We demonstrate that a low pH (around 6.8) is not required for our strategy, as glucose availability is already limiting the flux. On the contrary, we boosted glycolytic flux in glucose limitation by setting the pH to 7.4. This new approach led to a yield of lactic acid/glucose (Y L/G) around zero for the whole process time and high titers in our labs. We hypothesize that a higher carbon flux, resulting from a higher pH, may lead to more cells which produce more product. The relevance of this work aims at feeding mammalian cell cultures safely in limitation with a desired metabolic flux range. This resulted in extremely stable, low glucose levels, very robust pH profiles without acid/base interventions and a metabolic state in which lactic acid was consumed instead of being produced from day 1. With this contribution

  5. Metabolic Control in Mammalian Fed-Batch Cell Cultures for Reduced Lactic Acid Accumulation and Improved Process Robustness

    Directory of Open Access Journals (Sweden)

    Viktor Konakovsky

    2016-01-01

    Full Text Available Biomass and cell-specific metabolic rates usually change dynamically over time, making the “feed according to need” strategy difficult to realize in a commercial fed-batch process. We here demonstrate a novel feeding strategy which is designed to hold a particular metabolic state in a fed-batch process by adaptive feeding in real time. The feed rate is calculated with a transferable biomass model based on capacitance, which changes the nutrient flow stoichiometrically in real time. A limited glucose environment was used to confine the cell in a particular metabolic state. In order to cope with uncertainty, two strategies were tested to change the adaptive feed rate and prevent starvation while in limitation: (i inline pH and online glucose concentration measurement or (ii inline pH alone, which was shown to be sufficient for the problem statement. In this contribution, we achieved metabolic control within a defined target range. The direct benefit was two-fold: the lactic acid profile was improved and pH could be kept stable. Multivariate Data Analysis (MVDA has shown that pH influenced lactic acid production or consumption in historical data sets. We demonstrate that a low pH (around 6.8 is not required for our strategy, as glucose availability is already limiting the flux. On the contrary, we boosted glycolytic flux in glucose limitation by setting the pH to 7.4. This new approach led to a yield of lactic acid/glucose (Y L/G around zero for the whole process time and high titers in our labs. We hypothesize that a higher carbon flux, resulting from a higher pH, may lead to more cells which produce more product. The relevance of this work aims at feeding mammalian cell cultures safely in limitation with a desired metabolic flux range. This resulted in extremely stable, low glucose levels, very robust pH profiles without acid/base interventions and a metabolic state in which lactic acid was consumed instead of being produced from day 1. With

  6. Determination of Bacterial Growth in Culture Media

    International Nuclear Information System (INIS)

    Elly Ellyna Rashid; Shariza Hanim Zainal Abidin; Mok, P.S.

    2015-01-01

    Bacteria is one of the important microorganism in our daily life. Bacteria provides human beings with products in the field of medical, industry, food, agriculture and others. Determination of bacteria growth is important so that we can enjoy the most benefit from it. Spread-plate method is one of the methods to obtain the bacterial counts. Agar plates, such as Nutrient Agar or Plate Count Agar are usually used for this purpose. Bacterial culture will be diluted first before being spread on the agar plate and incubated at specific temperature. The number of bacteria in colony-forming unit (CFU) will be counted the next day. The count will be used to determine the bacterial growth. (author)

  7. Mixed-culture transcriptome analysis reveals the molecular basis of mixed-culture growth in Streptococcus thermophilus and Lactobacillus bulgaricus.

    Science.gov (United States)

    Sieuwerts, Sander; Molenaar, Douwe; van Hijum, Sacha A F T; Beerthuyzen, Marke; Stevens, Marc J A; Janssen, Patrick W M; Ingham, Colin J; de Bok, Frank A M; de Vos, Willem M; van Hylckama Vlieg, Johan E T

    2010-12-01

    Many food fermentations are performed using mixed cultures of lactic acid bacteria. Interactions between strains are of key importance for the performance of these fermentations. Yogurt fermentation by Streptococcus thermophilus and Lactobacillus bulgaricus (basonym, Lactobacillus delbrueckii subsp. bulgaricus) is one of the best-described mixed-culture fermentations. These species are believed to stimulate each other's growth by the exchange of metabolites such as folic acid and carbon dioxide. Recently, postgenomic studies revealed that an upregulation of biosynthesis pathways for nucleotides and sulfur-containing amino acids is part of the global physiological response to mixed-culture growth in S. thermophilus, but an in-depth molecular analysis of mixed-culture growth of both strains remains to be established. We report here the application of mixed-culture transcriptome profiling and a systematic analysis of the effect of interaction-related compounds on growth, which allowed us to unravel the molecular responses associated with batch mixed-culture growth in milk of S. thermophilus CNRZ1066 and L. bulgaricus ATCC BAA-365. The results indicate that interactions between these bacteria are primarily related to purine, amino acid, and long-chain fatty acid metabolism. The results support a model in which formic acid, folic acid, and fatty acids are provided by S. thermophilus. Proteolysis by L. bulgaricus supplies both strains with amino acids but is insufficient to meet the biosynthetic demands for sulfur and branched-chain amino acids, as becomes clear from the upregulation of genes associated with these amino acids in mixed culture. Moreover, genes involved in iron uptake in S. thermophilus are affected by mixed-culture growth, and genes coding for exopolysaccharide production were upregulated in both organisms in mixed culture compared to monocultures. The confirmation of previously identified responses in S. thermophilus using a different strain combination

  8. Single Cell Protein Production by Saccharomyces cerevisiae Using an Optimized Culture Medium Composition in a Batch Submerged Bioprocess.

    Science.gov (United States)

    Hezarjaribi, Mehrnoosh; Ardestani, Fatemeh; Ghorbani, Hamid Reza

    2016-08-01

    Saccharomyces cerevisiae PTCC5269 growth was evaluated to specify an optimum culture medium to reach the highest protein production. Experiment design was conducted using a fraction of the full factorial methodology, and signal to noise ratio was used for results analysis. Maximum cell of 8.84 log (CFU/mL) was resulted using optimized culture composed of 0.3, 0.15, 1, and 50 g L(-1) of ammonium sulfate, iron sulfate, glycine, and glucose, respectively at 300 rpm and 35 °C. Glycine concentration (39.32 % contribution) and glucose concentration (36.15 % contribution) were determined as the most effective factors on the biomass production, while Saccharomyces cerevisiae growth had showed the least dependence on ammonium sulfate (5.2 % contribution) and iron sulfate (19.28 % contribution). The most interaction was diagnosed between ammonium sulfate and iron sulfate concentrations with interaction severity index of 50.71 %, while the less one recorded for glycine and glucose concentration was equal to 8.12 %. An acceptable consistency of 84.26 % was obtained between optimum theoretical cell numbers determined by software of 8.91 log (CFU/mL), and experimentally measured one at optimal condition confirms the suitability of the applied method. High protein content of 44.6 % using optimum culture suggests that Saccharomyces cerevisiae is a good commercial case for single cell protein production.

  9. Batch culture fermentation of Penicillium chrysogenum and a report on the isolation, purification, identification and antibiotic activity of citrinin

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; DeSouza, L.; Kamat, T.; Rodrigues, C.; Naik, C.G.

    Batch fermentation of Penicillium chrysogenum, MTCC 5108 was carried out using potato dextrose broth medium prepared in seawater: distilled water (1:1). Biomass as dry weight was determined by gravimetric analysis. Citrinin, the main secondary...

  10. The improvement of the quality of polluted irrigation water through a phytoremediation process in a hydroponic batch culture system

    Science.gov (United States)

    Retnaningdyah, Catur

    2017-11-01

    The objective of this research was to determine the effectiveness of a phytoremediation process using some local hydro macrophytes to reduce fertilizer residue in irrigation water in order to support healthy agriculture and to prevent eutrophication and algae bloom in water. A phytoremediation process was carried out in a hydroponic floating system by using transparent plastic bags of 1 m in diameter and 1 m in height that were placed in collecting ponds before they were used for agricultural activities. Paddy soils were used as substrates in this system. The irrigation water was treated with nutrient enrichment (Urea and SP-36 fertilizers). Then, the system was planted with remediation actors (Azolla sp., Ipomoea aquatica, Limnocharis flava, Marsilea crenata, polyculture of those hydro macrophytes and control). The improvement of the water quality as a result of the phytoremediation process was characterized by a decline in the concentration of some physicochemical parameters, which were measured at 7 days after incubation, as well as an increase in the plankton diversity index value. The results showed that all of the hydro macrophytes used in this research, which was grown in the hydroponic batch culture system for a period of 7 days, were able to significantly improve the irrigation water quality, which was enriched by the synthetic fertilizers Urea and SP36. This was reflected by a significant decrease in the concentration of water TSS, nitrate, BOD, COD and total phosphate and an increase in the value of water DO at 7 days after incubation. Improvement of the water quality is also reflected in the increasing plankton diversity index value as a bioindicator of water pollution indicating a change in the pollution status from moderately polluted to slightly polluted at 7 days after incubation.

  11. Determination of some significant batch culture conditions affecting acetyl-xylan esterase production by Penicillium notatum NRRL-1249

    Directory of Open Access Journals (Sweden)

    Akhtar MN

    2011-05-01

    Full Text Available Abstract Background Acetyl-xylan esterase (AXE, EC 3.1.1.72 hydrolyses acetate group from the linear chain of xylopyranose residues bound by β-1,4-linkage. The enzyme finds commercial applications in bio-bleaching of wood pulp, treating animal feed to increase digestibility, processing food to increase clarification and converting lignocellulosics to feedstock and fuel. In the present study, we report on the production of an extracellular AXE from Penicillium notatum NRRL-1249 by solid state fermentation (SSF. Results Wheat bran at a level of 10 g (with 4 cm bed height was optimized as the basal substrate for AXE production. An increase in enzyme activity was observed when 7.5 ml of mineral salt solution (MSS containing 0.1% KH2PO4, 0.05% KCl, 0.05% MgSO4.7H2O, 0.3% NaNO3, 0.001% FeSO4.2H2O and 0.1% (v/w Tween-80 as an initial moisture content was used. Various nitrogen sources including ammonium sulphate, urea, peptone and yeast extract were compared for enzyme production. Maximal enzyme activity of 760 U/g was accomplished which was found to be highly significant (p ≤ 0.05. A noticeable enhancement in enzyme activity was observed when the process parameters including incubation period (48 h, initial pH (5, 0.2% (w/w urea as nitrogen source and 0.5% (v/w Tween-80 as a stimulator were further optimized using a 2-factorial Plackett-Burman design. Conclusion From the results it is clear that an overall improvement of more than 35% in terms of net enzyme activity was achieved compared to previously reported studies. This is perhaps the first report dealing with the use of P. notatum for AXE production under batch culture SSF. The Plackett-Burman model terms were found highly significant (HS, suggesting the potential commercial utility of the culture used (df = 3, LSD = 0.126.

  12. Decrease of UPR- and ERAD-related proteins in Pichia pastoris during methanol-induced secretory insulin precursor production in controlled fed-batch cultures.

    Science.gov (United States)

    Vanz, Ana Letícia; Nimtz, Manfred; Rinas, Ursula

    2014-02-13

    Pichia pastoris is a popular yeast preferably employed for secretory protein production. Secretion is not always efficient and endoplasmic retention of proteins with aberrant folding properties, or when produced at exaggerated rates, can occur. In these cases production usually leads to an unfolded protein response (UPR) and the induction of the endoplasmic reticulum associated degradation (ERAD). P. pastoris is nowadays also an established host for secretory insulin precursor (IP) production, though little is known about the impact of IP production on the host cell physiology, in particular under industrially relevant production conditions. Here, we evaluate the cellular response to aox1 promoter-controlled, secretory IP production in controlled fed-batch processes using a proteome profiling approach. Cells were first grown in a batch procedure using a defined medium with a high glycerol concentration. After glycerol depletion IP production was initiated by methanol addition which was kept constant through continuous methanol feeding. The most prominent changes of the intracellular proteome after the onset of methanol feeding were related to the enzymes of central carbon metabolism. In particular, the enzymes of the methanol dissimilatory pathway - virtually absent in the glycerol batch phase - dominated the proteome during the methanol fed-batch phase. Unexpectedly, a strong decrease of UPR and ERAD related proteins was also observed during methanol-induced IP production. Compared to non-producing control strains grown under identical conditions the UPR down-regulation was less pronounced indicating that IP production elicits a detectable but non prominent UPR response which is repressed by the general culture condition-dependent UPR down-regulation after the shift from glycerol to methanol. The passage of IP through the secretory pathway using an optimized IP vector and growing the strain at fed-batch conditions with a high initial glycerol concentration does

  13. Mathematical modeling of fed-batch fermentation ofSchizochytriumsp. FJU-512 growth and DHA production using a shift control strategy.

    Science.gov (United States)

    Zhang, Mingliang; Wu, Weibin; Guo, Xiaolei; Weichen, You; Qi, Feng; Jiang, Xianzhang; Huang, Jianzhong

    2018-03-01

    To obtain high-cell-density cultures of Schizochytrium sp. FJU-512 for DHA production, two stages of fermentation strategy were used and carbon/nitrogen ratio, DO and temperature were controlled at different levels. The final dry cell weight, total lipid production and DHA yield in 15 l bioreactor reached 103.9, 37.2 and 16.0 g/l, respectively. For the further study of microbial growth and DHA production dynamics, we established a set of kinetic models for the fed-batch production of DHA by Schizochytrium sp. FJU-512 in 15 and 100 l fermenters and a compensatory parameter n was integrated into the model in order to find the optimal mathematical equations. A modified Logistic model was proposed to fit the cell growth data and the following kinetic parameters were obtained: µ m  = 0.0525/h, X m  = 100 g/l and n  = 4.1717 for the 15 l bioreactor, as well as µ m  = 0.0382/h, X m  = 107.4371 g/l and n  = 10 for the 100 l bioreactor. The Luedeking-Piret equations were utilized to model DHA production, yielding values of α  = 0.0648 g/g and β  = 0.0014 g/g/h for the 15 l bioreactor, while the values of α and β obtained for the 100 l fermentation were 0.0209 g/g and 0.0030 g/g/h. The predicted results compared with experimental data showed that the established models had a good fitting precision and were able to exactly depict the dynamic features of the DHA production process.

  14. Population growth, demographic change, and cultural landscapes.

    Science.gov (United States)

    Woodgate, G; Sage, C

    1994-01-01

    The inclusion of both ecological and socioeconomic components within landscapes makes possible the perception of the hierarchical character of landscape organization. A research approach is needed to conceptualize cultural landscapes as the product of interaction between society and nature. Richard Norgaard's 1984 paper on coevolutionary agricultural development attempts to meet this challenge. Coevolution is the interactive synthesis of natural and social mechanisms of change that characterize the relationship between social systems and ecosystems. The relationship between population, consumption, and environmental changes is complex. Currently industrialized countries present the biggest threat to global environmental resources. The issue of carrying capacity is the corollary of population and the environment. It is primarily the technological factor rather than population that needs to be controlled. The relationship between rich and poor countries is determined by superior economic power. An analysis of landscape change is made, tracing the coevolution of society and environment from the end of the feudal era and making comparisons with continental Europe. Over the years since 1945 the need to realize potential economies of scale has resulted in a wholesale loss of woodlands, hedgerows, and small ponds in the UK. In a global context the likely impacts of population growth and demographic change on landscapes will be influenced by such socioeconomic factors as technology and affluence; policies that ignore cause and effect; and the traditional tendency to treat the environment as a waste repository and a supply depot.

  15. Impact of the freeze-drying process on product appearance, residual moisture content, viability, and batch uniformity of freeze-dried bacterial cultures safeguarded at culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Hellemans, Ann; De Vos, Paul

    2016-07-01

    In this study, causes of collapsed bacterial cultures in glass ampoules observed after freeze-drying were investigated as well as the influence of collapse on residual moisture content (RMC) and viability. Also, the effect of heat radiation and post freeze-drying treatments on the RMC was studied. Cake morphologies of 21 bacterial strains obtained after freeze-drying with one standard protocol could be classified visually into four major types: no collapse, porous, partial collapse, and collapse. The more pronounced the collapse, the higher residual moisture content of the freeze-dried product, ranging from 1.53 % for non-collapsed products to 3.62 % for collapsed products. The most important cause of collapse was the mass of the inserted cotton plug in the ampoule. Default cotton plugs with a mass between 21 and 30 mg inside the ampoule did not affect the viability of freeze-dried Aliivibrio fischeri LMG 4414(T) compared to ampoules without cotton plugs. Cotton plugs with a mass higher than 65 mg inside the ampoule induced a full collapsed product with rubbery look (melt-back) and decreasing viability during storage. Heat radiation effects in the freeze-drying chamber and post freeze-drying treatments such as exposure time to air after freeze-drying and manifold drying time prior to heat sealing of ampoules influenced the RMC of freeze-dried products. To produce uniform batches of freeze-dried bacterial strains with intact cake structures and highest viabilities, inserted cotton plugs should not exceed 21 mg per ampoule. Furthermore, heat radiation effects should be calculated in the design of the primary drying phase and manifold drying time before heat sealing should be determined as a function of exposure time to air.

  16. The effects of a reduced environmental deuterium concentration on growth of culture normal and neoplastic cells

    International Nuclear Information System (INIS)

    Bild, Walther; Haulica, Ion; Nastasa, V.

    2002-01-01

    In connection with studies on the effects of deuterium depleted water on radioprotection and immunostimulation, research was conducted to find out effects of environmental depleted deuterium upon culture cells growth. The reduction of deuterium concentration in cellular medium was achieved by forming the culture medium for RMPI 1640, Gibco BRL cells with under-deuterated water (produced at ICSI) with different deuterium concentration (30, 60, 90, 120 ppm), as compared with control batches in the same medium constituted from normal distilled water (145-150 ppm D/(D+H). A significant stimulation in the cellular growth due to deuterium depletion in the culture media was observed. Also, variations in growth rates and the profile of proliferation curves in neoplastic cells as compared with normal cells were observed, the same trend being observed in all cultures. Paradoxically, quantitative effects were observed, peaking at 90 ppm deuterium concentration rather than at a minimal concentration, as expected. The MTT test confirmed the stimulating effects of deuterium depletion. To put into evidence the immunity stimulation, the explant rat splenocytes from laboratory animals were grown, stimulated with Concanavaline A or bacterial Lipopolysaccharides of increasing concentration. Similar effects were observed

  17. Theories of Posttraumatic Growth: Cross-Cultural Perspectives

    Science.gov (United States)

    Splevins, Katie; Cohen, Keren; Bowley, Jake; Joseph, Stephen

    2010-01-01

    Posttraumatic growth is a concept that has been established within a Western cultural framework. This review examines whether there is a Western cultural bias in this concept, and related processes and outcomes, and whether any cultural bias has been incorporated into associated psychometric tools. It is concluded that, although at an abstract…

  18. Effects of culture systems on growth and economic performance of ...

    African Journals Online (AJOL)

    The effect of culture system on growth and economics performance of Orechromis niloticus (Nile tilapia) in concrete tanks was investigated. Four outdoor concrete tanks measuring 2.5 x 2 m was used for the study for 24 weeks culture period. The culture systems included the use of algae only at the stocking rates of 4 ...

  19. Effect of acetate to biomass ratio on simultaneous polyhydroxybutyrate generation and direct microbial growth in fast growing microbial culture.

    Science.gov (United States)

    Biros, Yester; Çokgör, Emine Ubay; Yağcı, Nevin; Pala-Ozkok, Ilke; Çakar, Zeynep Petek; Sözen, Seval; Orhon, Derin

    2014-11-01

    The study investigated the effect of variations in the acetate to biomass ratio on substrate storage potential, and the kinetics of substrate utilization. A series of batch experiments were conducted with biomass taken from the fill and draw reactor operated at a sludge age of 2 d. One of the batch reactors duplicated the substrate loading in the main reactor. The others were started with different initial acetate to biomass ratios both in lower and higher ranges. Increasing available acetate did not totally divert excess substrate to storage; the microbial culture adjusted the kinetics of the metabolic reactions to a higher growth rate so that more substrate could be utilized for direct growth at high acetate levels. Conversely, storage rate was increased, utilizing a higher substrate fraction for polyhydroxybutyrate generation when acetate concentration was lowered. The physiological and molecular bases of storage at low substrate levels were discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Using multi-parameter flow cytometry to monitor the yeast Rhodotorula glutinis CCMI 145 batch growth and oil production towards biodiesel.

    Science.gov (United States)

    da Silva, Teresa Lopes; Feijão, Daniela; Reis, Alberto

    2010-12-01

    Multi-parameter flow cytometry was used to monitor cell intrinsic light scatter, viability, and lipid content of Rhodotorula glutinis CCMI 145 cells grown in shake flasks. Changes in the side light scatter and forward light scatter were detected during the yeast batch growth, which were attributed to the different yeast growth phases. A progressive increase in the proportion of cells stained with PI (cells with permeabilized cytoplasmic membrane) was observed during the yeast growth, attaining 79% at the end of the fermentation. A high correlation between the Nile Red fluorescence intensity measured by flow cytometry and total lipid content assayed by the traditional gravimetric lipid analysis was found for this yeast, making this method a suitable and quick technique for the screening of yeast strains for lipid production and optimization of biofuel production bioprocesses. Medium growth optimization for enhancement of the yeast oil production is now in progress.

  1. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  2. Discrepancy between growth of Coccidioides immitis in bacterial blood culture media and a radiometric growth index

    International Nuclear Information System (INIS)

    Ampel, N.M.; Wieden, M.A.

    1988-01-01

    Spherules of Coccidioides immitis grew readily after inoculation in vented trypticase soy broth, biphasic brain heart infusion media, and aerobic tryptic soy broth bottles used in a radiometric system (BACTEC). However, visible growth was not accompanied by a significant radiometric growth index. Growth of C. immitis can be visually detected in routine bacterial blood culture media while the radiometric growth index remains negative

  3. Waste-water assay with continuous algal cultures: the effect of mercuric acetate on the growth of some marine dinoflagellates

    Energy Technology Data Exchange (ETDEWEB)

    Kayser, H.

    1976-01-01

    The effect of mercuric acetate was studied in culture experiments with the dinoflagellates Scrippsiella faeroense (Paulsen) Balech et Soares, Prorocentrum micans Ehrenberg and Gymnodinium splendens Lebour. Impairment of growth rates, in vivo chlorophyll fluorescence, maximum cell densities and morphological changes served as criteria for assessing sublethal influences. Tests were made using the batch- and continuous-culture techniques. Addition of Hg at concentrations of 0.001 mg.1/sup -1/ and higher resulted in reduction of relative growth rates. In a few cases populations recovered from the initial decline and showed new growth. Cell counts corresponded very closely to in vivo chlorophyll fluorescence measurements. Morphological variations were observed in S. faeroense, which responded (even in sublethal concentrations) by bursting its thecae, releasing naked motile cells and forming vegetative resting stages. The problems of optimal algal-bioassay methods are discussed also, in the light of results obtained by other authors.

  4. Growth and Plating of Cell Suspension Cultures of Datura Innoxia

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1974-01-01

    malate) or on NO3−-N alone. Dry weight yield was proportional to the amount of nitrate-N added (47 mg/mg N). Filtered suspension cultures containing single cells (plating cultures) could be grown in agar in petri dishes when NAA or 2,4-D were used as growth substances. Cells grew at densities above 500...

  5. Effect of mineral concentration of culture media without growth ...

    African Journals Online (AJOL)

    Owner

    Effect of mineral concentration of culture media without growth substances on the callogenesis of Atriplex ... Key words: Atriplex halimus, in vitro culture, callogenesis, mineral elements. INTRODUCTION. Atriplex are plants adapted to the .... Purple pigments was also observed on callus developed on G/20, G/50 and G/100.

  6. Fermentation characteristics of corn-, triticale-, and wheat-based dried distillers' grains with solubles in barley-based diets determined using continuous and batch culture systems.

    Science.gov (United States)

    Au, Findy; McKeown, Lisa E; McAllister, Tim A; Chaves, Alexandre V

    2010-09-01

    Dried distillers' grains with solubles (DDGS) are becoming increasingly available and popular as an alternative livestock feed. This study used continuous and batch culture techniques to compare the in vitro fermentation characteristics of diets containing corn-, triticale- or wheat-based DDGS at 200 g kg(-1) diet dry matter (DM) against a barley grain-based control diet. In continuous fermentation of wheat DDGS diet, total volatile fatty acid (VFA) concentration was decreased by 15.7% across sampling times and NH(3) concentration was quadrupled compared with control, whereas fermentations of corn- and triticale-DDGS diets were similar to the barley-based control. In batch cultures, corn DDGS differed from control only in increased culture pH. Compared with control diet, triticale DDGS yielded lower total gas production (140.94 versus 148.78 mL g(-1) DM) and in vitro DM digestibility (IVDMD; 0.509 versus 0.535). Wheat DDGS diet yielded decreased total gas production (123.49 mL g(-1) DM) and IVDMD (0.468), as well as total VFA production (105.84 versus 134.20 mmol L(-1)) and substantially increased ammonia concentration (151.61 versus 58.34 mg L(-1)) and acetate:propionate ratio (2.94 versus 1.11). Corn- and triticale- DDGS diets exhibited fermentation characteristics similar to the barley based control diet, consistent with in vivo findings that these diets yielded no adverse effects on production. In vitro ruminal fermentation of wheat DDGS diet differed significantly from control in several aspects including 2.6 to 6X higher ammonia concentrations. Copyright 2010 Society of Chemical Industry.

  7. Enhancement of erythroid colony growth in culture by hemin

    International Nuclear Information System (INIS)

    Porter, P.N.; Meints, R.H.; Mesner, K.

    1979-01-01

    Hemin was found to enhance the growth of murine erythroid colonies in culture. In the presence of 100 mU/ml erythropoietin (EPO), the addition of hemin (0.05-0.2 mM) resulted in the growth of twice as many colonies as were obtained with EPO alone. Hemin also significantly increased erythroid colony formation in culture in the absence of added EPO. Hemoblobin synthesis as measured by the incorporation of 59 Fe into cyclohexanone extractable heme was augmented in culture by hemin. Neither Δ-aminolevulinic acid, a hemin precursor, nor FeCl 3 increased colony number. (author)

  8. Microalgal Photosynthesis and Growth in Mass Culture

    NARCIS (Netherlands)

    Janssen, M.G.J.

    2016-01-01

    The development of large-scale outdoor microalgae production requires a thorough understanding of microalgal growth which should be encompassed in a mathematical model. The model should be as simple as possible allowing use in outdoor practice by persons with varying backgrounds. This chapter

  9. Optimized fed-batch fermentation of Scheffersomyces stipitis for efficient production of ethanol from hexoses and pentoses.

    Science.gov (United States)

    Unrean, Pornkamol; Nguyen, Nhung H A

    2013-03-01

    Scheffersomyces stipitis was cultivated in an optimized, controlled fed-batch fermentation for production of ethanol from glucose-xylose mixture. Effect of feed medium composition was investigated on sugar utilization and ethanol production. Studying influence of specific cell growth rate on ethanol fermentation performance showed the carbon flow towards ethanol synthesis decreased with increasing cell growth rate. The optimum specific growth rate to achieve efficient ethanol production performance from a glucose-xylose mixture existed at 0.1 h(-1). With these optimized feed medium and cell growth rate, a kinetic model has been utilized to avoid overflow metabolism as well as to ensure a balanced feeding of nutrient substrate in fed-batch system. Fed-batch culture with feeding profile designed based on the model resulted in high titer, yield, and productivity of ethanol compared with batch cultures. The maximal ethanol concentration was 40.7 g/L. The yield and productivity of ethanol production in the optimized fed-batch culture was 1.3 and 2 times higher than those in batch culture. Thus, higher efficiency ethanol production was achieved in this study through fed-batch process optimization. This strategy may contribute to an improvement of ethanol fermentation from lignocellulosic biomass by S. stipitis on the industrial scale.

  10. Quantitative image analysis as a tool for Yarrowia lipolytica dimorphic growth evaluation in different culture media.

    Science.gov (United States)

    Braga, A; Mesquita, D P; Amaral, A L; Ferreira, E C; Belo, I

    2016-01-10

    Yarrowia lipolytica, a yeast strain with a huge biotechnological potential, capable to produce metabolites such as γ-decalactone, citric acid, intracellular lipids and enzymes, possesses the ability to change its morphology in response to environmental conditions. In the present study, a quantitative image analysis (QIA) procedure was developed for the identification and quantification of Y. lipolytica W29 and MTLY40-2P strains dimorphic growth, cultivated in batch cultures on hydrophilic (glucose and N-acetylglucosamine (GlcNAc) and hydrophobic (olive oil and castor oil) media. The morphological characterization of yeast cells by QIA techniques revealed that hydrophobic carbon sources, namely castor oil, should be preferred for both strains growth in the yeast single cell morphotype. On the other hand, hydrophilic sugars, namely glucose and GlcNAc caused a dimorphic transition growth towards the hyphae morphotype. Experiments for γ-decalactone production with MTLY40-2P strain in two distinct morphotypes (yeast single cells and hyphae cells) were also performed. The obtained results showed the adequacy of the proposed morphology monitoring tool in relation to each morphotype on the aroma production ability. The present work allowed establishing that QIA techniques can be a valuable tool for the identification of the best culture conditions for industrial processes implementation. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Effects of Lavandula officinalis and Equisetum arvense dry extracts and isoquercitrin on the fermentation of diets varying in forage contents by rumen microorganisms in batch culture.

    Science.gov (United States)

    Broudiscou, L P; Lassalas, B

    2000-01-01

    The short-term actions of Lavandula officinalis and Equisetum arvense dry extracts, and of isoquercitrin, flavonoid present in Equisetum arvense, on in vitro fermentation by rumen microbes were studied in batch culture. The orchard grass hay:barley ratios in the three experimental diets were 100:0, 75:25, 50:50 on a DM basis. The production rates of all volatile fatty acids except isobutyrate were strongly influenced by the composition of the diet and to a lesser extent, by plant extracts, with significant interactions between both factors. When hay was the only substrate, the addition of L. officinalis and E. arvense enhanced the fermentation rate by 50%, through an increased release of acetate and propionate. On the contrary, with the two other diets, the fermentation rate was strongly lowered by isoquercitrin. Gas outputs were not significantly influenced by plant extracts.

  12. High level expression of Glomerella cingulata cutinase in dense cultures of Pichia pastoris grown under fed-batch conditions.

    Science.gov (United States)

    Seman, W M K Wan; Bakar, S A; Bukhari, N A; Gaspar, S M; Othman, R; Nathan, S; Mahadi, N M; Jahim, J; Murad, A M A; Bakar, F D Abu

    2014-08-20

    A Pichia pastoris transformant carrying the cutinase cDNA of Glomerella cingulata was over-expressed in a 5L bioreactor (2.0L working volume) under fed-batch conditions. Bioreactor experiments rely on varying selected parameters in repeated rounds of optimisation: here these included duration of induction, pH and temperature. Highest cell densities (320gL(-1) wet cell weight) with a cutinase production of 3800mgL(-1) and an activity of 434UmL(-1) were achieved 24h after induction with methanol in basal salt medium (at pH 5 and 28°C). Characterisation of the cutinase showed that it was stable between pH 6 and pH 11, had an optimum pH of 8.0 and retained activity for 30min at 50°C (optimum temperature 25°C).The preferred substrates of G. cingulata cutinase were the medium- to long-chain ρ-nitrophenyl esters of ρ-nitrophenylcaprylate (C8), ρ-nitrophenyllaurate (C12) and ρ-nitrophenylmyristate (C14), with the highest catalytic efficiency, kcat/Km of 7.7±0.7mM(-1)s(-1) for ρ-nitrophenylcaprylate. Microscopic analyses showed that the G. cingulata cutinase was also capable of depolymerising the high molecular weight synthetic polyester, polyethylene terephthalate. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Biodegradation of pulp and paper mill effluent by co-culturing ascomycetous fungi in repeated batch process.

    Science.gov (United States)

    Rajwar, Deepika; Paliwal, Rashmi; Rai, J P N

    2017-08-31

    The competence of novel fungal consortium, consisting of Nigrospora sp. LDF00204 (accession no. KP732542) and Curvularia lunata LDF21 (accession no. KU664593), was investigated for the treatment of pulp and paper mill effluent. Fungal consortium exhibited enhanced biomass production under optimized medium conditions, i.e., glucose as carbon (C), sodium nitrate as nitrogen (N), C/N 1.5:0.5, pH 5, temperature 30 °C, and agitation 140 rpm, and significantly reduced biochemical oxygen demand (85.6%), chemical oxygen demand (80%), color (82.3%), and lignin concentration (76.1%) under catalytic enzyme activity; however, unutilized ligninolytic enzymes, such as laccase (Lac), manganese peroxidase (MnP), and lignin peroxidase (LiP), were observed to be 13.5, 11.4, and 9.4 U/ml after the third cycle of effluent treatment in repeated batch process. Scanning electron microscopy (SEM) of fungal consortium revealed their compatibility through intermingled hyphae and spores, while the FTIR spectra confirmed the alteration of functional groups ensuring structural changes during the effluent treatment. Gas chromatography/mass spectroscopy (GC-MS) analysis showed the reduction of complex compounds and development of numerous low-molecular-weight metabolites, such as 1-3-dimethyl benzene, 2-chloro-3-methyl butane, pentadecanoic acid, and 1-2-benzene dicarboxylic acid, during the treatment, demonstrating the massive potential of the novel fungal consortium to degrade recalcitrant industrial pollutants.

  14. Biosynthesis of highly enriched 13C-lycopene for human metabolic studies using repeated batch tomato cell culturing with 13C-glucose

    Science.gov (United States)

    Moran, Nancy E.; Rogers, Randy B.; Lu, Chi-Hua; Conlon, Lauren E.; Lila, Mary Ann; Clinton, Steven K.; Erdman, John W.

    2013-01-01

    While putative disease-preventing lycopene metabolites are found in both tomato (Solanum lycopersicum) products and in their consumers, mammalian lycopene metabolism is poorly understood. Advances in tomato cell culturing techniques offer an economical tool for generation of highly-enriched 13C-lycopene for human bioavailability and metabolism studies. To enhance the 13C-enrichment and yields of labeled lycopene from the hp-1 tomato cell line, cultures were first grown in 13C-glucose media for three serial batches and produced increasing proportions of uniformly labeled lycopene (14.3 +/− 1.2 %, 39.6 +/− 0.5 %, and 48.9 +/− 1.5% with consistent yields (from 5.8 to 9 mg/L). An optimized 9-day-long 13C-loading and 18-day-long labeling strategy developed based on glucose utilization and lycopene yields, yielded 13C-lycopene with 93% 13C isotopic purity, and 55% of isotopomers were uniformly labeled. Furthermore, an optimized acetone and hexane extraction led to a four-fold increase in lycopene recovery from cultures compared to a standard extraction. PMID:23561155

  15. Mineralization and growth of cultured embryonic skeletal tissue in microgravity

    Science.gov (United States)

    Klement, B. J.; Spooner, B. S.

    1999-01-01

    Microgravity provides a unique environment in which to study normal and pathological phenomenon. Very few studies have been done to examine the effects of microgravity on developing skeletal tissue such as growth plate formation and maintenance, elongation of bone primordia, or the mineralization of growth plate cartilage. Embryonic mouse premetatarsal triads were cultured on three space shuttle flights to study cartilage growth, differentiation, and mineralization, in a microgravity environment. The premetatarsal triads that were cultured in microgravity all formed cartilage rods and grew in length. However, the premetatarsal cartilage rods cultured in microgravity grew less in length than the ground control cartilage rods. Terminal chondrocyte differentiation also occurred during culture in microgravity, as well as in the ground controls, and the matrix around the hypertrophied chondrocytes was capable of mineralizing in both groups. The same percentage of premetatarsals mineralized in the microgravity cultures as mineralized in the ground control cultures. In addition, the sizes of the mineralized areas between the two groups were very similar. However, the amount of 45Ca incorporated into the mineralized areas was significantly lower in the microgravity cultures, suggesting that the composition or density of the mineralized regions was compromised in microgravity. There was no significant difference in the amount of 45Ca liberated from prelabeled explants in microgravity or in the ground controls.

  16. Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain

    NARCIS (Netherlands)

    Zelle, R.M.; De Hulster, E.; Kloezen, W.; Pronk, J.T.; Van Maris, A.J.A.

    2010-01-01

    A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter(-1) of malate at a yield of 0.42 mol (mol glucose)(-1) in calcium carbonate-buffered shake flask cultures. With shake flasks, process

  17. Growth of Igbo-Ora virus in some tissue cultures.

    Science.gov (United States)

    Olaleye, O D; Omilabu, S A; Baba, S S

    1990-08-01

    VERO, MRC5, MDCK, and MA104 cells were tested for their ability to support the growth of Igbo-Ora virus. In VERO and MRC5 cell cultures the virus replicated to high titres causing apparent cytopathic effects (CPE) (cell rounding and complete lysis) and formation of complement fixing antigens. The virus grew to lower infectious titre in MDCK and MA104 cell cultures in which CPE was limited to cell rounding only.

  18. Hormonal regulation of wheat growth during hydroponic culture

    Science.gov (United States)

    Wetherell, Donald

    1988-01-01

    Hormonal control of root growth has been explored as one means to alleviate the crowding of plant root systems experienced in prototype hydroponic biomass production chambers being developed by the CELSS Breadboard Project. Four plant hormones, or their chemical analogs, which have been reported to selectively inhibit root growth, were tested by adding them to the nutrient solutions on day 10 of a 25 day growth test using spring wheat in hydroponic cultures. Growth and morphological changes is both shoot and root systems were evaluated. In no case was it possible to inhibit root growth without a comparable inhibition of shoot growth. It was concluded that this approach is unlikely to prove useful for wheat.

  19. Production of Gymnemic Acid Depends on Medium, Explants, PGRs, Color Lights, Temperature, Photoperiod, and Sucrose Sources in Batch Culture of Gymnema sylvestre

    Directory of Open Access Journals (Sweden)

    A. Bakrudeen Ali Ahmed

    2012-01-01

    Full Text Available Gymnema sylvestre (R.Br. is an important diabetic medicinal plant which yields pharmaceutically active compounds called gymnemic acid (GA. The present study describes callus induction and the subsequent batch culture optimization and GA quantification determined by linearity, precision, accuracy, and recovery. Best callus induction of GA was noticed in MS medium combined with 2,4-D (1.5 mg/L and KN (0.5 mg/L. Evaluation and isolation of GA from the calluses derived from different plant parts, namely, leaf, stem and petioles have been done in the present case for the first time. Factors such as light, temperature, sucrose, and photoperiod were studied to observe their effect on GA production. Temperature conditions completely inhibited GA production. Out of the different sucrose concentrations tested, the highest yield (35.4 mg/g d.w was found at 5% sucrose followed by 12 h photoperiod (26.86 mg/g d.w. Maximum GA production (58.28 mg/g d.w was observed in blue light. The results showed that physical and chemical factors greatly influence the production of GA in callus cultures of G. sylvestre. The factors optimized for in vitro production of GA during the present study can successfully be employed for their large-scale production in bioreactors.

  20. Growth of melanocytes in human epidermal cell cultures

    International Nuclear Information System (INIS)

    Staiano-Coico, L.; Hefton, J.M.; Amadeo, C.; Pagan-Charry, I.; Madden, M.R.; Cardon-Cardo, C.

    1990-01-01

    Epidermal cell cultures were grown in keratinocyte-conditioned medium for use as burn wound grafts; the melanocyte composition of the grafts was studied under a variety of conditions. Melanocytes were identified by immunohistochemistry based on a monoclonal antibody (MEL-5) that has previously been shown to react specifically with melanocytes. During the first 7 days of growth in primary culture, the total number of melanocytes in the epidermal cultures decreased to 10% of the number present in normal skin. Beginning on day 2 of culture, bipolar melanocytes were present at a mean cell density of 116 +/- 2/mm2; the keratinocyte to melanocyte ratio was preserved during further primary culture and through three subpassages. Moreover, exposure of cultures to mild UVB irradiation stimulated the melanocytes to proliferate, suggesting that the melanocytes growing in culture maintained their responsiveness to external stimuli. When the sheets of cultured cells were enzymatically detached from the plastic culture flasks before grafting, melanocytes remained in the basal layer of cells as part of the graft applied to the patient

  1. Differences in carbohydrate profiles in batch culture grown planktonic and biofilm cells of Amphora rostrata Wm. Sm

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Bhosle, N.B.

    phase of growth of some diatoms (Percival 1970). Roszkowski et al. (1989) have reported that fucose rich polysaccharide inhibits the adhesion process of metastatic sarcoma L-1 cells in lungs of mice. In view of this, it is possible that fucose rich... and Biochemistry, IIB. Academic Press, London, pp 537-568 Roszkowski W, Beuth J, Ko HL, Uhlenbruck G, Pulverer G. 1989. Blocking of lectin like adhesion molecules on pulmonary cells inhibits lung sarcoma L colonization in BALB/c-mice. Experientia 45...

  2. Evaluation of conidia production and mycelial growth in solid culture ...

    African Journals Online (AJOL)

    It is important to know the ability of native strains to carry out the process of sporulation and growth in different conditions and to determine their possible potential as biological control of pests of agricultural importance, mainly in citrus areas. The objective of this study was to evaluate five different solid culture media for the ...

  3. Effects of culture systems on growth and economic performance of ...

    African Journals Online (AJOL)

    IFEOMA PIUS

    2013-07-03

    Jul 3, 2013 ... Key words: Culture system, growth performance, economic performance, Oreochromic niloticus. INTRODUCTION. Food is a basic necessity of life, second only to air and water. The global food equation recognizes two major components namely; food crop component and animal protein component ...

  4. Culture, Gender and Growth. Policy Insights, No. 15

    Science.gov (United States)

    Jutting, Johannes; Morrisson, Christian

    2005-01-01

    While the overall picture for gender equality is still gloomy, recent changes in family institutions in some countries provide an enlightening example. Developing countries are starting to reform cultural barriers to gender equality that limit their growth prospects. Morocco, Algeria, Egypt and some states of India are some examples of countries…

  5. Effect of mineral concentration of culture media without growth ...

    African Journals Online (AJOL)

    The studies on the in vitro culture of the Atriplex halimus, a fooder plant of arid zones of Tunisia, have shown an induction of the callogenesis on intact seedlings cultivated on medium without growth substances. Two media, which differ only by the nature and the concentration of macroelements, were tested. Assays of ...

  6. Influence of mixed culture system on the growth performance of ...

    African Journals Online (AJOL)

    DR TONUKARI NYEROVWO

    2013-05-22

    May 22, 2013 ... This study describes a novel strategy to improve the α-galactosidase and invertase production of. Saccharomyces cerevisiae by co-cultivating it with Aspergillus oryzae. In the mixed culture, the growth of the both strains was repressed, and the protein synthesis for the yeast cell wall was promoted.

  7. Growth effects on mixed culture of Dunaliella salina and ...

    African Journals Online (AJOL)

    AJL

    2011-10-10

    Oct 10, 2011 ... length of 680 nm using UV-spectrophotometer (TU-1900, Beijing) every two days during the entire cultural period to monitor the cell growth. Cell density was monitored and recorded with a hemocytometer (XB.K.25, Shanghai) under optical microscope. (Olympus CX41, Japan) at the same time of the day on ...

  8. Influence of mixed culture system on the growth performance of ...

    African Journals Online (AJOL)

    This study describes a novel strategy to improve the α-galactosidase and invertase production of Saccharomyces cerevisiae by co-cultivating it with Aspergillus oryzae. In the mixed culture, the growth of the both strains was repressed, and the protein synthesis for the yeast cell wall was promoted significantly. As a result ...

  9. Growth and Cultural Characteristics of Cordyceps cardinalis Collected from Korea

    Science.gov (United States)

    Sung, Gi-Ho; Shrestha, Bhushan; Han, Sang-Kuk; Kim, Soo-Young

    2010-01-01

    Cordyceps cardinalis was reported in Japan and the USA in 2004, and its fruiting bodies have recently been cultured in Korea. Herbarium specimens preserved at the Cordyceps Research Institute, Mushtech, Korea were revised and identified as C. cardinalis, based on morphological characters and conidial structures. Most of the C. cardinalis specimens were collected from Mt. Halla in Jeju-do. The effects of various nutritional sources and environmental conditions such as temperature and pH on mycelial growth of C. cardinalis were studied. Oatmeal agar, Martin's peptone dextrose agar, and Schizophyllum (mushroom) genetics complete medium plus yeast extract resulted in the best mycelial growth. Among carbon sources, cereals, and nitrogen sources, maltose, oatmeal, and peptone resulted in the best mycelial growth respectively. Mineral salts helped to increase growth rate but only resulted in thin mycelial density, similar to water agar. A temperature of 25℃ and a pH of 7 resulted in the highest mycelial growth. Based on these results, a Cordyceps cardinalis composite medium (CCM) was formulated with 1% maltose, 2% oatmeal, 1% peptone, and 2% agar. Use of the CCM resulted in slightly better mycelial growth than that of other commonly used agar media. Only organic nitrogen sources imparted a reddish pigmentation to the agar media, but this character diminished after several subcultures. A 7 day culture duration resulted in the best mycelial growth. PMID:23956666

  10. Radiation adaptive response for the growth of cultured glial cells

    International Nuclear Information System (INIS)

    Suzuki, S.; Miura, Y.; Kano, M.; Toda, T.; Urano, S.

    2003-01-01

    Full text: To examine the molecular mechanism of radiation adaptive response (RAR) for the growth of cultured glial cells and to investigate the influence of aging on the response, glial cells were cultured from young and aged rats (1 month and 24 months old). RAR for the growth of glial cells conditioned with a low dose of X-rays and subsequently exposed to a high dose of X-rays was examined for cell number and BrdU incorporation. Involvement of the subcellular signaling pathway factors in RAR was investigated using their inhibitors, activators and mutated glial cells. RAR was observed in cells cultured from young rats, but was not in cells from aged rats. The inhibitors of protein kinase C (PKC) and DNA-dependent protein kinase (DNA-PK) or phosphatidylinositol 3-kinase (PI3K) suppressed RAR. The activators of PKC instead of low dose irradiation also caused RAR. Moreover, glial cells cultured from severe combined immunodeficiency (scid) mice (CB-17 scid) and ataxia-telangiectasia (AT) cells from AT patients showed no RAR. These results indicated that PKC, ATM, DNAPK and/or PI3K were involved in RAR for growth and BrdU incorporation of cultured glial cells and RAR decreased with aging. Proteomics data of glial cells exposed to severe stress of H 2 O 2 or X-rays also will be presented in the conference since little or no difference has not been observed with slight stress yet

  11. Stochastic modelling of Listeria monocytogenes single cell growth in cottage cheese with mesophilic lactic acid bacteria from aroma producing cultures.

    Science.gov (United States)

    Østergaard, Nina Bjerre; Christiansen, Lasse Engbo; Dalgaard, Paw

    2015-07-02

    A stochastic model was developed for simultaneous growth of low numbers of Listeria monocytogenes and populations of lactic acid bacteria from the aroma producing cultures applied in cottage cheese. During more than two years, different batches of cottage cheese with aroma culture were analysed for pH, lactic acid concentration and initial concentration of lactic acid bacteria. These data and bootstrap sampling were used to represent product variability in the stochastic model. Lag time data were estimated from observed growth data (lactic acid bacteria) and from literature on L. monocytogenes single cells. These lag time data were expressed as relative lag times and included in growth models. A stochastic model was developed from an existing deterministic growth model including the effect of five environmental factors and inter-bacterial interaction [Østergaard, N.B, Eklöw, A and Dalgaard, P. 2014. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese. International Journal of Food Microbiology. 188, 15-25]. Growth of L. monocytogenes single cells, using lag time distributions corresponding to three different stress levels, was simulated. The simulated growth was subsequently compared to growth of low concentrations (0.4-1.0 CFU/g) of L. monocytogenes in cottage cheese, exposed to similar stresses, and in general a good agreement was observed. In addition, growth simulations were performed using population relative lag time distributions for L. monocytogenes as reported in literature. Comparably good predictions were obtained as for the simulations performed using lag time data for individual cells of L. monocytogenes. Therefore, when lag time data for individual cells are not available, it was suggested that relative lag time distributions for L. monocytogenes can be used as a qualified default assumption when simulating growth of low concentrations of L. monocytogenes. Copyright

  12. Evaluation on prebiotic properties of β-glucan and oligo-β-glucan from mushrooms by human fecal microbiota in fecal batch culture

    Directory of Open Access Journals (Sweden)

    Chiraphon Chaikliang

    2015-11-01

    Full Text Available Background: β-glucan is dietary fiber, a structural polysaccharide, β-linked linear chains of D-glucose polymers with variable frequency of branches. β-glucan is isolated from different sources such as cell walls of baker’s yeast (Saccharomyces cerevisiae, cereals (oat and barley and various species of mushrooms. Among 8 mushrooms in the study, Schizophylum commune Fr and Auricularia auricula Judae had the highest in β-glucan contents and the cheapest cost of mushroom per content of β-glucan, respectively. Even the function of β-glucan on immune modulation has been known however no report on interaction between β-glucan and human gut microbiota. Gut microbiota is thought to have health effects by interaction with non-digestible component particular fermentable dietary fiber. It is important to correlate the specific groups of the microbial communities associated with β-glucan fermentation and the consequential SCFA profiles. β-glucan from mushroom may has potential prebiotic function similar to those from commercial yeast (Saccharomyces cerevisiae β-glucan. Objective: To evaluate on prebiotic properties of soluble β-glucans and oligo-β-glucans from Schizophylum commune Fr and Auricularia auricula Judae by fecal fermentation in batch culture. Methods: In vitro fecal fermentation in anaerobic batch cultures under simulated conditions similar to human colon with human faecal samples from three donors were performed. Comparison on 3 β-glucans and 2 oligo-β-glucans have been studied. Sample was taken at 0 h, 24 h and 48 h to analyze the numbers of bacterial changes by fluorescent in situ hybridization (FISH technique. Short chain fatty acids (SCFA were analyzed by HPLC. The prebiotic index (PI was calculated according to the change of 5 specific bacterial genus within 48 h fermentation. Results: Soluble β-glucan from Auricularia auricula Judae increased numbers of bifidobacteria and lactobacillus significantly (P<0.05. The PI of

  13. Detection of Sialic Acid-Utilising Bacteria in a Caecal Community Batch Culture Using RNA-Based Stable Isotope Probing

    Directory of Open Access Journals (Sweden)

    Wayne Young

    2015-03-01

    Full Text Available Sialic acids are monosaccharides typically found on cell surfaces and attached to soluble proteins, or as essential components of ganglioside structures that play a critical role in brain development and neural transmission. Human milk also contains sialic acid conjugated to oligosaccharides, glycolipids, and glycoproteins. These nutrients can reach the large bowel where they may be metabolised by the microbiota. However, little is known about the members of the microbiota involved in this function. To identify intestinal bacteria that utilise sialic acid within a complex intestinal community, we cultured the caecal microbiota from piglets in the presence of 13C-labelled sialic acid. Using RNA-based stable isotope probing, we identified bacteria that consumed 13C-sialic acid by fractionating total RNA in isopycnic buoyant density gradients followed by 16S rRNA gene analysis. Addition of sialic acid caused significant microbial community changes. A relative rise in Prevotella and Lactobacillus species was accompanied by a corresponding reduction in the genera Escherichia/Shigella, Ruminococcus and Eubacterium. Inspection of isotopically labelled RNA sequences suggests that the labelled sialic acid was consumed by a wide range of bacteria. However, species affiliated with the genus Prevotella were clearly identified as the most prolific users, as solely their RNA showed significantly higher relative shares among the most labelled RNA species. Given the relevance of sialic acid in nutrition, this study contributes to a better understanding of their microbial transformation in the intestinal tract with potential implications for human health.

  14. Influence of extracellular pH on growth, viability, cell size, acidification activity, and intracellular pH of Lactococcus lactis in batch fermentations.

    Science.gov (United States)

    Hansen, Gunda; Johansen, Claus Lindvald; Marten, Gunvor; Wilmes, Jacqueline; Jespersen, Lene; Arneborg, Nils

    2016-07-01

    In this study, we investigated the influence of three extracellular pH (pHex) values (i.e., 5.5, 6.5, and 7.5) on the growth, viability, cell size, acidification activity in milk, and intracellular pH (pHi) of Lactococcus lactis subsp. lactis DGCC1212 during pH-controlled batch fermentations. A universal parameter (e.g., linked to pHi) for the description or prediction of viability, specific acidification activity, or growth behavior at a given pHex was not identified. We found viability as determined by flow cytometry to remain high during all growth phases and irrespectively of the pH set point. Furthermore, regardless of the pHex, the acidification activity per cell decreased over time which seemed to be linked to cell shrinkage. Flow cytometric pHi determination demonstrated an increase of the averaged pHi level for higher pH set points, while the pH gradient (pHi-pHex) and the extent of pHi heterogeneity decreased. Cells maintained positive pH gradients at a low pHex of 5.5 and even during substrate limitation at the more widely used pHex 6.5. Moreover, the strain proved able to grow despite small negative or even absent pH gradients at a high pHex of 7.5. The larger pHi heterogeneity at pHex 5.5 and 6.5 was associated with more stressful conditions resulting, e.g., from higher concentrations of non-dissociated lactic acid, while the low pHi heterogeneity at pHex 7.5 most probably corresponded to lower concentrations of non-dissociated lactic acid which facilitated the cells to reach the highest maximum active cell counts of the three pH set points.

  15. Optimal control of a batch bioreactor for the production of a novel ...

    African Journals Online (AJOL)

    related plant diseases, however, research and development of biological prevention and controlling are of great importance. In this work, the effects of pH and temperature on cell growth and CF66I formation in batch culture of Burkholderia cepecia ...

  16. Culture Conditions for the Mycelial Growth of Ganoderma applanatum.

    Science.gov (United States)

    Jo, Woo-Sik; Cho, Yun-Ju; Cho, Doo-Hyun; Park, So-Deuk; Yoo, Young-Bok; Seok, Soon-Ja

    2009-06-01

    Ganoderma applanatum is one of the most popular medicinal mushrooms due to the various biologically active components it produces. This study was conducted to obtain basic information regarding the mycelial culture conditions of Ganoderma applanatum. Based on the colony diameter and mycelial density, PDA, YMA and MCM media were suitable for the mycelial growth of the mushroom. The optimum temperature for mycelial growth was found to be 25~30℃. The optimum carbon and nitrogen sources were mannose and dextrin, respectively, and the optimum C/N ratio was 2 to 10 when 2% glucose was used. Other minor components required for the optimal growth included thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and MgSO4·7H2O, KH2PO4 and NaCl as mineral salts.

  17. Growth-rate dependency of de novo resveratrol production in chemostat cultures of an engineered Saccharomyces cerevisiae strain.

    Science.gov (United States)

    Vos, Tim; de la Torre Cortés, Pilar; van Gulik, Walter M; Pronk, Jack T; Daran-Lapujade, Pascale

    2015-09-14

    Saccharomyces cerevisiae has become a popular host for production of non-native compounds. The metabolic pathways involved generally require a net input of energy. To maximize the ATP yield on sugar in S. cerevisiae, industrial cultivation is typically performed in aerobic, sugar-limited fed-batch reactors which, due to constraints in oxygen transfer and cooling capacities, have to be operated at low specific growth rates. Because intracellular levels of key metabolites are growth-rate dependent, slow growth can significantly affect biomass-specific productivity. Using an engineered Saccharomyces cerevisiae strain expressing a heterologous pathway for resveratrol production as a model energy-requiring product, the impact of specific growth rate on yeast physiology and productivity was investigated in aerobic, glucose-limited chemostat cultures. Stoichiometric analysis revealed that de novo resveratrol production from glucose requires 13 moles of ATP per mole of produced resveratrol. The biomass-specific production rate of resveratrol showed a strong positive correlation with the specific growth rate. At low growth rates a substantial fraction of the carbon source was invested in cellular maintenance-energy requirements (e.g. 27 % at 0.03 h(-1)). This distribution of resources was unaffected by resveratrol production. Formation of the by-products coumaric, phloretic and cinnamic acid had no detectable effect on maintenance energy requirement and yeast physiology in chemostat. Expression of the heterologous pathway led to marked differences in transcript levels in the resveratrol-producing strain, including increased expression levels of genes involved in pathways for precursor supply (e.g. ARO7 and ARO9 involved in phenylalanine biosynthesis). The observed strong differential expression of many glucose-responsive genes in the resveratrol producer as compared to a congenic reference strain could be explained from higher residual glucose concentrations and higher

  18. Pro Spring Batch

    CERN Document Server

    Minella, Michael T

    2011-01-01

    Since its release, Spring Framework has transformed virtually every aspect of Java development including web applications, security, aspect-oriented programming, persistence, and messaging. Spring Batch, one of its newer additions, now brings the same familiar Spring idioms to batch processing. Spring Batch addresses the needs of any batch process, from the complex calculations performed in the biggest financial institutions to simple data migrations that occur with many software development projects. Pro Spring Batch is intended to answer three questions: *What? What is batch processing? What

  19. Estimation of the Maximum Theoretical Productivity of Fed-Batch Bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Bomble, Yannick J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); St. John, Peter C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Crowley, Michael F [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-18

    A key step towards the development of an integrated biorefinery is the screening of economically viable processes, which depends sharply on the yields and productivities that can be achieved by an engineered microorganism. In this study, we extend an earlier method which used dynamic optimization to find the maximum theoretical productivity of batch cultures to explicitly include fed-batch bioreactors. In addition to optimizing the intracellular distribution of metabolites between cell growth and product formation, we calculate the optimal control trajectory of feed rate versus time. We further analyze how sensitive the productivity is to substrate uptake and growth parameters.

  20. Fed-batch bioreactor process with recombinant Saccharomyces cerevisiae growing on cheese whey

    Directory of Open Access Journals (Sweden)

    R. Rech

    2006-12-01

    Full Text Available Saccharomyces cerevisiae strain W303 was transformed with two yeast integrative plasmids containing Kluyveromyces lactis LAC4 and LAC12 genes that codify beta-galactosidase and lactose permease respectively. The BLR030 recombinant strain was selected due to its growth and beta-galactosidase production capacity. Different culture media based on deproteinized cheese whey (DCW were tested and the best composition (containing DCW, supplemented with yeast extract 1 %, and peptone 3 % (w/v was chosen for bioreactor experiments. Batch, and fed-batch cultures with linear ascending feeding for 25 (FB25, 35 (FB35, and 50 (FB50 hours, were performed. FB35 and FB50 produced the highest beta-galactosidase specific activities (around 1,800 U/g cells, and also the best productivities (180 U/L.h. Results show the potential use of fed-batch cultures of recombinant S. cerevisiae on industrial applications using supplemented whey as substrate.

  1. Modelling the Effect of Different Substrates and Temperature on the Growth and Lactic Acid Production by Lactobacillus amylovorus DSM 20531T in Batch Process

    Directory of Open Access Journals (Sweden)

    Antonija Trontel

    2010-01-01

    Full Text Available Amylolytic lactic acid bacterium Lactobacillus amylovorus DSM 20531T utilised glucose, sucrose and starch as a sole carbon and energy source. The three substrates were completely depleted from MRS medium during batch cultivations carried out in a laboratory scale stirred tank bioreactor at constant temperature (40 °C and pH value (5.5. Under the tested conditions, the bacterium was capable of conducting simultaneously starch hydrolysis and fermentation. A mixture of two stereoisomers, D-(–- and L-(+-lactic acid, was produced in all cases by highly efficient homofermentative bioprocess with 0.93 to 1 g of lactate produced per g of total (consumed substrate. The effect of temperature on the kinetics of cell growth and lactic acid production by the amylolytic strain in the starch-containing medium was also investigated. Efficient simultaneous saccharification and fermentation (SSF was obtained at 35, 40 and 45 °C with completely degraded complex carbohydrate in 8 to 12 h and the product yield coefficient in the range from 0.91 to 0.93 g/g. Maximum values for substrate consumption rate (0.89 h^–1, maximum specific growth rate (0.87 h^–1, product formation rate (2.01 h^–1, and productivity of lactic acid (1.45 g/(L·h were obtained at 45 °C, while maximum biomass concentration (4.38 g/L was attained at 40 °C. The ratio of the two stereoisomeric forms of produced lactic acid was strongly affected by the temperature. Unstructured kinetic model was used to describe the consumption of the three substrates, bacterial biomass formation and lactic acid production by L. amylovorus DSM 20531T. The dependence of biokinetic parameters on temperature was described by cardinal temperature model. The applied models successfully predicted all experimental data.

  2. Product formation from thiophene by a mixed bacterial culture. Influence of benzene as growth substrate

    DEFF Research Database (Denmark)

    Rivas, Isabelle Marie; Mosbæk, Hans; Arvin, Erik

    2003-01-01

    The influence of benzene as a growth substrate on the cometabolic conversion of thiophene was investigated in batch systems with microorganisms originating from an creosote contaminated site. Benzene was shown to stimulate the conversion of thiophene with a first-order rate, during the initial...

  3. Growth Culture Conditions and Nutrient Signaling Modulating Yeast Chronological Longevity

    Directory of Open Access Journals (Sweden)

    Júlia Santos

    2012-01-01

    Full Text Available The manipulation of nutrient-signaling pathways in yeast has uncovered the impact of environmental growth conditions in longevity. Studies using calorie restriction show that reducing glucose concentration of the culture media is sufficient to increase replicative and chronological lifespan (CLS. Other components of the culture media and factors such as the products of fermentation have also been implicated in the regulation of CLS. Acidification of the culture media mainly due to acetic acid and other organic acids production negatively impacts CLS. Ethanol is another fermentative metabolite capable of inducing CLS reduction in aged cells by yet unknown mechanisms. Recently, ammonium was reported to induce cell death associated with shortening of CLS. This effect is correlated to the concentration of NH4+ added to the culture medium and is particularly evident in cells starved for auxotrophy-complementing amino acids. Studies on the nutrient-signaling pathways regulating yeast aging had a significant impact on aging-related research, providing key insights into mechanisms that modulate aging and establishing the yeast as a powerful system to extend knowledge on longevity regulation in multicellular organisms.

  4. AMPK regulation of the growth of cultured human keratinocytes

    International Nuclear Information System (INIS)

    Saha, Asish K.; Persons, Kelly; Safer, Joshua D.; Luo Zhijun; Holick, Michael F.; Ruderman, Neil B.

    2006-01-01

    AMP kinase (AMPK) is a fuel sensing enzyme that responds to cellular energy depletion by increasing processes that generate ATP and inhibiting others that require ATP but are not acutely necessary for survival. In the present study, we examined the relationship between AMPK activation and the growth (proliferation) of cultured human keratinocytes and assessed whether the inhibition of keratinocyte growth by vitamin D involves AMPK activation. In addition, we explored whether the inhibition of keratinocyte proliferation as they approach confluence could be AMPK-related. Keratinocytes were incubated for 12 h with the AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR). At concentrations of 10 -4 and 10 -3 M, AICAR inhibited keratinocyte growth by 50% and 95%, respectively, based on measurements of thymidine incorporation into DNA. It also increased AMPK and acetyl CoA carboxylase phosphorylation (P-AMPK and P-ACC) and decreased the concentration of malonyl CoA confirming that AMPK activation had occurred. Incubation with the thiazolidinedione, troglitazone (10 -6 M) caused similar alterations in P-AMPK, P-ACC, and cell growth. In contrast, the well known inhibition of keratinocyte growth by 1,25-dihydroxyvitamin D 3 (10 -7 and 10 -6 M) was not associated with changes in P-AMPK or P-ACC. Like most cells, the growth of keratinocytes diminished as they approached confluence. Thus, it was of note that we found a progressive increase in P-AMPK (1.5- to 2-fold, p 3 is AMPK-independent

  5. Viability and growth of feline preantral follicles in vitro cultured with insulin growth factor and epidermal growth factor supplemented medium.

    Science.gov (United States)

    Alves, A E; Padilha-Nakaghi, L C; Pires-Butler, E A; Apparicio, M; Silva, Nam; Motheo, T F; Vicente, Wrr; Luvoni, G C

    2017-04-01

    In vitro culture of ovarian preantral follicles has emerged as a reproductive technology aimed at obtaining large amount of oocytes for in vitro embryo production. The addition of growth factors (GF) in the in vitro culture of preantral follicles of different species has provided superior results of follicular development, antrum formation and proliferation of granulosa cells. However, there are only few reports regarding the use of these factors on feline preantral follicle in vitro culture. Thus, the aim of this study was to investigate the effect of a combination of IGF-1 and EGF on in vitro viability and growth of preantral follicles and enclosed oocytes collected from domestic cats. A total of 64 follicles characterized by multilayer granulosa cells were isolated and individually cultured for 6 days (T6) in minimum essential medium supplemented with IGF-1+ EGF (100 ng/ml each) or without (control). A higher percentage of follicles were viable after culture with GF than without, and an increase in size when IGF-1+ EGF were added to the medium (170 ± 32.4 μm (T0) vs. 201 ± 22.3 μm (T6); p  .05). These data suggest that the addition of IGF-1 and EGF to the culture medium promotes the in vitro development of preantral follicles of cats. © 2016 Blackwell Verlag GmbH.

  6. Comparison of transcriptional heterogeneity of eight genes between batch Desulfovibrio vulgaris biofilm and planktonic culture at a single-cell level

    Directory of Open Access Journals (Sweden)

    Zhenhua eQi

    2016-04-01

    Full Text Available Sulfate-reducing bacteria (SRB biofilm formed on metal surfaces can change the physicochemical properties of metals and cause metal corrosion. To enhance understanding of differential gene expression in Desulfovibrio vulgaris under planktonic and biofilm growth modes, a single-cell based RT-qPCR approach was applied to determine gene expression levels of 8 selected target genes in four sets of the 31 individual cells isolated from each growth condition (i.e., biofilm formed on a stainless steel (SS) and planktonic cultures, exponential and stationary phases. The results showed obvious gene-expression heterogeneity for the target genes among D. vulgaris single cells of both biofilm and planktonic cultures. In addition, an increased gene-expression heterogeneity in the D. vulgaris biofilm when compared with the planktonic culture was also observed for seven out of eight selected genes, which may be contributing to the increased complexity in terms of structures and morphology in the biofilm. Moreover, the results showed up-regulation of DVU0281 gene encoding exopolysaccharide biosynthesis protein, and down-regulation of genes involved in energy metabolism (i.e., DVU0434 and DVU0588, stress responses (i.e., DVU2410 and response regulator (i.e., DVU3062 in the D. vulgaris biofilm cells. Finally, the gene (DVU2571 involved in iron transportation was found down-regulated, and two genes (DVU1340 and DVU1397 involved in ferric uptake repressor and iron storage were up-regulated in D. vulgaris biofilm, suggesting their possible roles in maintaining normal metabolism of the D. vulgaris biofilm under environments of high concentration of iron. This study showed that the single-cell based analysis could be a useful approach in deciphering metabolism of microbial biofilms.

  7. Cultivo mixotrófico da microalga Spirulina platensis em batelada alimentada Mixotrophic growth of Spirulina platensis in fed-batch mode

    Directory of Open Access Journals (Sweden)

    Adriana Muliterno

    2005-12-01

    Full Text Available A Spirulina platensis tem sido estudada devido a seu alto valor protéico, digestibilidade e por apresentar quantidades significativas de ácidos graxos poliinsaturados, vitaminas, fenólicos e ficocianina, podendo ser utilizada na alimentação humana. A utilização de nutrientes de baixo custo é um fator importante na produção da cianobactéria por possibilitar a redução de custos de processo. Objetivou-se com este trabalho estudar o cultivo mixotrófico da S. platensis por meio da adição de uma fonte orgânica de carbono (glicose em modo bateladaalimentada. Foi utilizado um Planejamento Fatorial Completo 2³ para o cultivo e as variáveis de estudo foram a concentração de glicose (0,5 gL-1 e 1,0 gL-1, a diluição do meio Zarrouk (50% e 75% e a iluminância (1800 lux e 3000 lux. A concentração celular máxima obtida foi de 5,38 gL-1 com uma velocidade específica máxima de crescimento de 0,0063 h-1, nas condições de 0,5 gL-1 de glicose, diluição do meio de 75% e iluminância de 3000 lux.The cyanobacterium Spirulina platensis has been studied due to its high content (~65% of highly digestible protein as well as significant amounts of polyunsaturated fatty acids, phenolics, vitamins, minerals and phycocyanin which could be useful in the human nutrition. The use of nutrients of low costs in the cyanobacterium growth could reduce the costs of production. We studied the fed-batch mixotrophic growth of the S. platensis in Zarrouk's medium with glucose (0.5 gL-1 and 1.0 gL-1 as carbon source and also investigated the effects of dilution (50% and 75%, with water and illumination (1,800 lux and 3,000 lux using a 2³ factorial design. The maximum celular concentration of 5.38 gL-1 and maximum specific growth rate of 0.0063 h-1 were obtained with a glucose concentration of 0.5 gL-1, 50% dilution and 1800 lux of illuminance.

  8. Sphagnum growth in floating cultures: Effect of planting design

    Directory of Open Access Journals (Sweden)

    Y. Hoshi

    2017-11-01

    Full Text Available To establish rapid and stable Sphagnum growth, capitulum culture of a selected strain of S. palustre was carried out using a floating culture method. Four planting treatments were tested at mountain and urban sites in Kumamoto Prefecture on Kyushu Island, south-west Japan. Capitula were planted in colonies of different sizes on 30 cm square floating rafts, but with strict control of the number (75–77 of capitula per raft. The initial cover of live green Sphagnum ranged from 15 to 20 %. Growth of the colonies was followed throughout the growing season (April to November of 2008. After three months, green coverage rates reached 40–50 % in all planting treatments. At the end of the growing season, the highest Sphagnum cover (almost 90 % at the urban site was recorded in the planting treatment with eleven re-introduced colonies of seven capitula (‘11×7cap’, while the highest capitulum number and biomass (dry weight gain occurred in the ‘4×19cap’ planting treatment. Average stem elongation ranged from 5 cm to 7 cm in the ‘77×1cap’ and ‘4×19cap’planting treatments, respectively, indicating that the larger sized colony grew longer stems. However, contrary to expectation, the ‘4×19cap’planting treatment - which had the largest colony size - did not deliver the highest number of newly formed side shoots.

  9. Estimation of autotrophic maximum specific growth rate constant--experience from the long-term operation of a laboratory-scale sequencing batch reactor system.

    Science.gov (United States)

    Su, Yu-min; Makinia, Jacek; Pagilla, Krishna R

    2008-04-01

    The autotrophic maximum specific growth rate constant, muA,max, is the critical parameter for design and performance of nitrifying activated sludge systems. In literature reviews (i.e., Henze et al., 1987; Metcalf and Eddy, 1991), a wide range of muA,max values have been reported (0.25 to 3.0 days(-1)); however, recent data from several wastewater treatment plants across North America revealed that the estimated muA,max values remained in the narrow range 0.85 to 1.05 days(-1). In this study, long-term operation of a laboratory-scale sequencing batch reactor system was investigated for estimating this coefficient according to the low food-to-microorganism ratio bioassay and simulation methods, as recommended in the Water Environment Research Foundation (Alexandria, Virginia) report (Melcer et al., 2003). The estimated muA,max values using steady-state model calculations for four operating periods ranged from 0.83 to 0.99 day(-1). The International Water Association (London, United Kingdom) Activated Sludge Model No. 1 (ASM1) dynamic model simulations revealed that a single value of muA,max (1.2 days(-1)) could be used, despite variations in the measured specific nitrification rates. However, the average muA,max was gradually decreasing during the activated sludge chlorination tests, until it reached the value of 0.48 day(-1) at the dose of 5 mg chlorine/(g mixed liquor suspended solids x d). Significant discrepancies between the predicted XA/YA ratios were observed. In some cases, the ASM1 predictions were approximately two times higher than the steady-state model predictions. This implies that estimating this ratio from a complex activated sludge model and using it in simple steady-state model calculations should be accepted with great caution and requires further investigation.

  10. Factors Causing Compositional Changes in Soy Protein Hydrolysates and Effects on Cell Culture Functionality

    NARCIS (Netherlands)

    Gupta, A.J.; Gruppen, H.; Maes, D.; Boots, J.W.; Wierenga, P.A.

    2013-01-01

    Soy protein hydrolysates significantly enhance cell growth and recombinant protein production in cell cultures. The extent of this enhancement in cell growth and IgG production is known to vary from batch to batch. This can be due to differences in the abundance of different classes of compounds

  11. Novel culture medium for the axenic growth of Balamuthia mandrillaris.

    Science.gov (United States)

    Lares-Jiménez, Luis Fernando; Gámez-Gutiérrez, Ricardo Alfredo; Lares-Villa, Fernando

    2015-08-01

    Until now, for axenic cultivation of Balamuthia mandrillaris, the BM-3 culture medium and the Modified Chang's special medium have been the only ones recommended, but they have some disadvantages, as both require many components and their preparations are laborious. Therefore, we developed a novel culture medium for B. mandrillaris axenic cultivation. Each one of the 11 components of BM-3 was combined with Cerva's medium as basal culture medium. Ten strains of B. mandrillaris including the reference strain CDC:V039 and 9 environmental isolates were used during trials. After testing all combinations, the basal medium complemented with 10× Hank's balanced salt solution was the only one that supported confluent growth of B. mandrillaris. Cell shape and motility of trophozoites were normal. This developed medium is as useful as BM-3 for axenization. The development of a cheaper and easy-to-prepare medium for B. mandrillaris opens the possibility of increasing its study. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Fungal growth in culture media simulating an extreme environment.

    Science.gov (United States)

    Alvarez-Pérez, Sergio; Blanco, José L; Alba, Patricia; García, Marta E

    2011-01-01

    There is an increasing interest in the study of microorganisms that inhabit extreme environments for reasons that vary from gaining insight into the origin of life to the searching of new biotechnological applications. In this work, we studied the tolerance of fungi isolated from the Aguas Agrias Stream (AAS; Tharsis, Huelva, Spain), an acidic metal-rich environment, to a culture medium prepared with water from this extreme ecosystem (AASW medium). The ability of some culture collection strains of moulds and yeasts to grow on AASW medium was also assessed. For moulds, a tolerance index was calculated by dividing the growth diameter of colonies on AASW medium by the diameter in the control medium, and their germinative potential was recorded. For yeasts and yeast-like fungi, the minimum inhibitory concentration of AASW was determined. In general, the fungi isolated from the AAS showed differences in their ability to germinate and grow on AASW medium. Collection strains of the genus Aspergillus could grow on AASW medium, but showed some differences in tolerance when compared to environmental isolates. Extremotolerant fungi can manifest differences in their tolerance to culture media that simulate the conditions of their natural habitat. The results of this work suggest that the ability of fungi to grow in acidic, metal-rich environments might be more widespread than previously thought, and highlight the importance of determining the factors that are responsible for tolerance to these extreme environments. Copyright © 2010 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  13. Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

    Science.gov (United States)

    Stampfer, Martha R; Garbe, James C

    2015-02-24

    Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

  14. Development of Fed-Batch Cultivation Strategy for Efficient Oxytetracycline Production by Streptomyces rimosus at Semi-Industrial Scale

    Directory of Open Access Journals (Sweden)

    Elsayed Ahmed Elsayed

    2015-10-01

    Full Text Available ABSTRACTOxytetracycline (OTC production byStreptomyces rimosus was studied in batch and fed-batch cultures in shake flask and bioreactor levels using semi-defined medium. First, the effect of glucose concentration on OTC production and growth kinetics was studied intensively. The optimal glucose concentration in the medium was 15 g/L. Higher glucose concentrations supported higher biomass production by less volumetric and specific antibiotic production. Based on these data, cultivations were carried out at semi-industrial scale 15 L bioreactor in batch culture. At bioreactor level, cell growth and OTC production were higher compared to the shake flask culture by about 18 and 38%, respectively. During the bioreactor cultivation, glucose was totally consumed after only 48 h. Thus, the fed-batch experiment was designed for mono-glucose feeding and complete medium feeding to increase the OTC production by overcoming carbon limitations. The results showed that the fed-batch culture using constant glucose feeding strategy with rate of 0.33 g/L/h produced 1072 mg/L. On the other hand, feeding with complete medium resulted in 45% higher biomass but less OTC production by about 26% compared to mono-glucose fed culture. A further improvement in this process was achieved in by keeping the dissolved oxygen (DO value at 60% saturation by cascading the glucose feeding pump with the DO controller. The later feeding strategy resulted in higher antibiotic production, reaching 1414 mg/L after 108 h.

  15. Minimal requirements for exponential growth of Lactococcus lactis

    DEFF Research Database (Denmark)

    Jensen, Peter Ruhdal; Hammer, Karin

    1993-01-01

    A minimal growth medium containing glucose, acetate, vitamins, and eight amino acids allowed for growth of Lactococcus lactis subsp. lactis, with a specific growth rate in batch culture of mu = 0.3 h-1. With 19 amino acids added, the growth rate increased to mu = 0.7 h-1 and the exponential growth...

  16. Growth and biomass production with enhanced {beta}-glucan and dietary fibre contents of Ganoderma australe ATHUM 4345 in a batch-stirred tank bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Papaspyridi, Lefki-Maria; Christakopoulos, Paul [BIOtechMASS Unit, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens (Greece); Katapodis, Petros [BIOtechMASS Unit, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens (Greece); Biotechnology Laboratory, Department of Biological Applications and Technologies, University of Ioannina, Ioannina (Greece); Gonou-Zagou, Zacharoula; Kapsanaki-Gotsi, Evangelia [Department of Ecology and Systematics, Faculty of Biology, National and Kapodistrian University of Athens, Athens (Greece)

    2011-02-15

    In this study we maximized biomass production by the basidiomycete Ganoderma australe ATHUM 4345, a species of pharmaceutical interest as it is a valuable source of nutraceuticals, including dietary fibers and glucans. We used the Biolog FF MicroPlate to screen 95 different carbon sources for growth monitoring. The pattern of substrate catabolism forms a substrate assimilation fingerprint, which is useful in selecting components for media optimization of maximum biomass production. Response surface methodology, based on the central composite design was applied to explore the optimum concentrations of carbon and nitrogen sources of culture medium in shake flask cultures. When the improved culture medium was tested in a 20-L stirred tank bioreactor, using 13.7 g/L glucose and 30.0 g/L yeast extract, high biomass yields (10.1{+-}0.4 g/L) and productivity of 0.09 g L{sup -1} h{sup -1} were obtained. The yield coefficients for total glucan and dietary fibers on biomass formed were 94.82{+-}6 and 341.15{+-}12.3 mg/g mycelium dry weight, respectively. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

    Directory of Open Access Journals (Sweden)

    Stojičić Dragana

    2012-01-01

    Full Text Available This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.

  18. Effects Of Heavy Metals On Growing Cultures Of Chlorella emersonii ...

    African Journals Online (AJOL)

    Under batch culture conditions no growth occurred with any of the silver concentrations tested. Chlorella that had been exposed to silver (1.0 mg/l) prior to cultivation without added metal showed growth. Above concentrations of 1.0 mg/l exposure there was no growth. Copper stimulated growth of Chlorella under continuous ...

  19. Spring batch essentials

    CERN Document Server

    Rao, P Raja Malleswara

    2015-01-01

    If you are a Java developer with basic knowledge of Spring and some experience in the development of enterprise applications, and want to learn about batch application development in detail, then this book is ideal for you. This book will be perfect as your next step towards building simple yet powerful batch applications on a Java-based platform.

  20. Microspectroscopic investigation of the membrane clogging during the sterile filtration of the growth media for mammalian cell culture.

    Science.gov (United States)

    Cao, Xiaolin; Loussaert, James A; Wen, Zai-qing

    2016-02-05

    Growth media for mammalian cell culture are very complex mixtures of several dozens of ingredients, and thus the preparation of qualified media is critical to viable cell density and final product titers. For liquid media prepared from powdered ingredients, sterile filtration is required prior to use to safeguard the cell culture process. Recently one batch of our prepared media failed to pass through the sterile filtration due to the membrane clogging. In this study, we report the root cause analysis of the failed sterile filtration based on the investigations of both the fouling media and the clogged membranes with multiple microspectroscopic techniques. Cellular particles or fragments were identified in the fouling media and on the surfaces of the clogged membranes, which were presumably introduced to the media from the bacterial contamination. This study demonstrated that microspectroscopic techniques may be used to rapidly identify both microbial particles and inorganic precipitates in the cell culture media. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Growth and accumulation of flavan-3-ol in Camellia sinensis through callus culture and suspension culture method

    Directory of Open Access Journals (Sweden)

    Sutini Sutini

    2017-02-01

    Full Text Available This study was aimed to assess flavan-3-ol biomass in C. sinensis through callus cultures and suspension cultures derived from leaf explants. Callus initiation of both cultures were using Murashige and Skoog medium were enriched with plant growth regulators Naphtha-lene Acetic Acid 3.0 mg/L and kinetin 2.0 mg/L. The procedures in this study were: (1 callus initiation by cutting the leaves of C. sinen-sis shoots then planted on Murashige and Skoog medium that were enriched with plant growth regulators, (2 sub callus culture on fresh medium that enriched with the same growth regulators, (3 suspension culture initiation of liquid callus, (4 growth examination of callus and suspension cultures in week 12, (5 examination of qualitative-quantitative content of flavan-3-olin suspension cultures at week 4. The results show that suspension cultures contain biomass flavan-3-ol that increase in the same manner of the increase of callus age and weight

  2. Extracellular production of a glycolipid biosurfactant, mannosylerythritol lipid, by Candida sp. SY16 using fed-batch fermentation.

    Science.gov (United States)

    Kim, Hee-Sik; Jeon, Jong-Woon; Kim, Byung-Hyuk; Ahn, Chi-Yong; Oh, Hee-Mock; Yoon, Byung-Dae

    2006-04-01

    Candida sp. strain SY16 produces a glycolipid-type biosurfactant, mannosylerythritol lipid (MEL-SY16), which can reduce the surface tension of a culture broth from 72 to 30 dyne cm(-1) and highly emulsify hydrocarbons when cultured in soybean-oil-containing media. As such, laboratory-scale fermentation for MEL-SY16 production was performed using optimized conditions. In batch fermentation, MEL-SY16 was mainly produced during the stationary phase of growth, and the concentration of MEL-SY16 reached 37 g l(-1) after 200 h. The effect of pH control on the production of MEL-SY16 was also examined in batch fermentation. The highest production yield of MEL-SY16 was when the pH was controlled at 4.0, and the production was significantly improved compared to batch fermentation without pH control. In fed-batch fermentation, glucose and soybean oil (1:1, w/w) were used in combination as the initial carbon sources for cell growth, and soybean oil was used as the feeding carbon source during the MEL production phase. The feeding of soybean oil resulted in the disappearance of any foam and a sharp increase in the MEL production until 200 h, at which point the concentration of MEL-SY16 was 95 g l(-1). Among the investigated culture systems, the highest MEL-SY16 production and volumetric production rate were achieved with fed-batch fermentation.

  3. EFFECTS OF CULTURE TANK SECTIONS ON GROWTH OF ...

    African Journals Online (AJOL)

    Dr. (Mrs) Jenyo-Oni

    EFFECTS OF THE SHAPE OF CULTURE TANKS ON PRODUCTION OF THE. AFRICAN CATFISH Clarias ... Three culture tank shapes (circular, rectangular and square) made of plastic material, having the ..... and space for fish culture. Since total costs incurred remains one of the most important factor in the evaluation of.

  4. SIMULATION INVESTIGATIONS TOWARDS THE DEVELOPMENT OF A BACTERIAL BIOPESTICIDE FED-BATCH REACTOR

    Directory of Open Access Journals (Sweden)

    Cunha C.C.F. da

    1998-01-01

    Full Text Available In this work, the growth of Bacillus thuringiensis var. israelensis, a bioinsecticide producer, is investigated. Experiments were carried out in batch mode in order to obtain kinetic model parameters that were further applied to simulate fed-batch processes. The fed-batch mode allows more flexibility in the control of the substrate concentration in the culture medium. Different techniques, such as constant feeding, "bang-bang" control and model based control (exponential feeding and singular control, were compared. For the techniques based on a model, combinations of models with and without a substrate inhibition parameter were used to represent the simulated process and the internal model of the feeding controller. Singular control based on the model with an inhibition parameter proved to be the most robust controller.

  5. SPS batch spacing optimisation

    CERN Document Server

    Velotti, F M; Carlier, E; Goddard, B; Kain, V; Kotzian, G

    2017-01-01

    Until 2015, the LHC filling schemes used the batch spac-ing as specified in the LHC design report. The maximumnumber of bunches injectable in the LHC directly dependson the batch spacing at injection in the SPS and hence onthe MKP rise time.As part of the LHC Injectors Upgrade project for LHCheavy ions, a reduction of the batch spacing is needed. In thisdirection, studies to approach the MKP design rise time of150ns(2-98%) have been carried out. These measurementsgave clear indications that such optimisation, and beyond,could be done also for higher injection momentum beams,where the additional slower MKP (MKP-L) is needed.After the successful results from 2015 SPS batch spacingoptimisation for the Pb-Pb run [1], the same concept wasthought to be used also for proton beams. In fact, thanksto the SPS transverse feed back, it was already observedthat lower batch spacing than the design one (225ns) couldbe achieved. For the 2016 p-Pb run, a batch spacing of200nsfor the proton beam with100nsbunch spacing wasreque...

  6. Studies on the growth behavior of Chlorella, Haematococcus and ...

    African Journals Online (AJOL)

    Growth studies were conducted on green algae Chlorella, Scenedesmus and Haematococcus strains in batch mode cultures. In this study, the effect of sodium bicarbonate salt (NaHCO3) and carbon dioxide (CO2) gas as carbon source on microalgal cultures were investigated. For this purpose, growth response of the ...

  7. Batch-to-batch model improvement for cooling crystallization

    OpenAIRE

    Forgione , Marco; Birpoutsoukis , Georgios; Bombois , Xavier; Mesbah , Ali; Daudey , Peter; Van Den Hof , Paul

    2015-01-01

    International audience; Two batch-to-batch model update strategies for model-based control of batch cooling crystallization are presented. In Iterative Learning Control, a nominal process model is adjusted by a non-parametric, additive correction term which depends on the difference between the measured output and the model prediction in the previous batch. In Iterative Identification Control, the uncertain model parameters are iteratively estimated using the measured batch data. Due to the d...

  8. Comparison of Fluorescence Microscopy and Different Growth Media Culture Methods for Acanthamoeba Keratitis Diagnosis.

    Science.gov (United States)

    Peretz, Avi; Geffen, Yuval; Socea, Soergiu D; Pastukh, Nina; Graffi, Shmuel

    2015-08-01

    Acanthamoeba keratitis (AK), a potentially blinding infection of the cornea, is caused by a free-living protozoan. Culture and microscopic examination of corneal scraping tissue material is the conventional method for identifying Acanthamoeba. In this article, we compared several methods for AK diagnosis of 32 patients: microscopic examination using fluorescent dye, specific culture on growth media-non-nutrient agar (NNA), culture on liquid growth media-peptone yeast glucose (PYG), and TYI-S-33. AK was found in 14 patients. Thirteen of the specimens were found AK positive by fluorescence microscopic examination, 11 specimens were found AK positive on PYG growth media, and 9 specimens were found AK positive on TYI-S-33 growth media. Only five specimens were found AK positive on NNA growth media. Therefore, we recommend using fluorescence microscopy technique and culture method, especially PYG liquid media. © The American Society of Tropical Medicine and Hygiene.

  9. Stimulating growth of starter cultures of raw sausages

    OpenAIRE

    Keniyz Nadezhda Viktorovna; Nesterenko Anton Alekseevich

    2015-01-01

    Activation of starter cultures in cold smoked sausage production is one of the most significant technological approaches which allows speeding up fermentation and decreasing the time for air drying of cold smoked sausages. During the research and experimental findings it is confirmed that the activation of starter cultures can be reached by using electromagnetic treatment.

  10. Growth of cultured porcine retinal pigment epithelial cells

    DEFF Research Database (Denmark)

    Wiencke, A.K.; Kiilgaard, Jens Folke; Nicolini, Jair

    2003-01-01

    To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation.......To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation....

  11. Comparison of growth kinetics between static and dynamic cultures of human induced pluripotent stem cells.

    Science.gov (United States)

    Kato, Yuma; Kim, Mee-Hae; Kino-Oka, Masahiro

    2018-02-02

    Understanding the fundamental mechanisms that govern the growth kinetics of human induced pluripotent stem cells (hiPSCs) contributes to culture design strategies to improve large-scale production. Two hiPSC lines (Tic and 253G1) were cultured under static and dynamic suspension conditions, and growth kinetics were compared during early (24-48 h), middle (48-72 h), and late (72-96 h) stages. In 2D static culture, similar growth profiles were observed for both hiPSC lines. However, there were significant differences in growth profile patterns and aggregate morphologies between hiPSC lines grown in 3D static and dynamic cultures. Based on immunostaining comparing the two hiPSC lines, surface distribution of collagen type I was observed in aggregates of the Tic line, but not in those of the 253G1 line. Compared to that in 3D static culture, the numbers of cells at 96 h were significantly decreased in 3D dynamic culture. The apparent specific growth rate (μ app ) of the Tic line was maintained continuously throughout culture, whereas that of the 253G1 line decreased gradually with culture until the late phase, at which time this parameter was reduced to μ app  = (0.85 ± 0.71) × 10 -2  h -1 . This indicates that during the growth of hiPSCs in 3D dynamic culture, cells were damaged by liquid flow, which disrupted the cell-synthesized extracellular matrix (ECM). These results demonstrate that cell-synthesized ECM is an important factor affecting cell growth and morphology, and that changes to the ECM within aggregates lead to reduced growth abilities in dynamic culture. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Growth-supporting activity for Legionella pneumophila in tap water cultures and implication of hartmannellid amoebae as growth factors.

    Science.gov (United States)

    Wadowsky, R M; Butler, L J; Cook, M K; Verma, S M; Paul, M A; Fields, B S; Keleti, G; Sykora, J L; Yee, R B

    1988-11-01

    Photosynthetic cyanobacteria, heterotrophic bacteria, free-living amoebae, and ciliated protozoa may support growth of Legionella pneumophila. Studies were done with two tap water cultures (WS1 and WS2) containing L. pneumophila and associated microbiota to characterize growth-supporting activity and assess the relative importance of the microbiota in supporting multiplication of L. pneumophila. The water cultures were incubated in the dark at 35 degrees C. The growth-supporting factor(s) was separated from each culture by filtration through 1-micron-pore-size membrane filters. The retentate was then suspended in sterile tap water. Multiplication of L. pneumophila occurred when both the retentate suspension and the filtrate from either culture were inoculated into sterile tap water. L. pneumophila did not multiply in tap water inoculated with only the filtrate, even though filtration did not reduce the concentration of L. pneumophila or heterotrophic bacteria in either culture. Growth-supporting activity of the retentate suspension from WS1 was inactivated at 60 degrees C but unaffected at 0, 25, and 45 degrees C after 30-min incubations. Filtration experiments indicated that the growth-supporting factor(s) in WS1 was 2 to 5 micron in diameter. Ciliated protozoa were not detected in either culture. Hartmannellid amoebae were conclusively demonstrated in WS2 but not in WS1. L. pneumophila multiplied in tap water inoculated with the amoebae (10(3)/ml) and the 1-micron filtrate of WS2. No multiplication occurred in tap water inoculated with the filtrate only. Growth-supporting activity for L. pneumophila may be present in plumbing systems; hartmannellid amoebae appear to be important determinants of multiplication of L. pneumophila in some tap water cultures.

  13. Heuristics for batching and sequencing in batch processing machines

    Directory of Open Access Journals (Sweden)

    Chuda Basnet

    2016-12-01

    Full Text Available In this paper, we discuss the “batch processing” problem, where there are multiple jobs to be processed in flow shops. These jobs can however be formed into batches and the number of jobs in a batch is limited by the capacity of the processing machines to accommodate the jobs. The processing time required by a batch in a machine is determined by the greatest processing time of the jobs included in the batch. Thus, the batch processing problem is a mix of batching and sequencing – the jobs need to be grouped into distinct batches, the batches then need to be sequenced through the flow shop. We apply certain newly developed heuristics to the problem and present computational results. The contributions of this paper are deriving a lower bound, and the heuristics developed and tested in this paper.

  14. Favourable culture conditions for mycelial growth of Hydnum ...

    African Journals Online (AJOL)

    In this study, factors such as pH, temperature, carbon and nitrogen sources that affect mycelial growth of Hydnum repandum, a medicinal mushroom, were investigated. Different inoculum media for vegetative inoculum production were also examined. The best suitable pH for mycelial growth was found to be 5.5. Among ...

  15. Population growth, economic security, and cultural change in wilderness counties

    Science.gov (United States)

    Paul A. Lorah

    2000-01-01

    A familiar version of the “jobs versus the environment” argument asserts that wilderness areas limit economic growth by locking up potentially productive natural resources. Analysis of the development paths of rural Western counties shows that this is unlikely: the presence of Wilderness is correlated with income, employment and population growth. Similarly, Wilderness...

  16. 6-Gingerol inhibits hair shaft growth in cultured human hair follicles and modulates hair growth in mice.

    Science.gov (United States)

    Miao, Yong; Sun, Yabin; Wang, Wenjun; Du, Benjun; Xiao, Shun-e; Hu, Yijue; Hu, Zhiqi

    2013-01-01

    Ginger (Zingiber officinale) has been traditionally used to check hair loss and stimulate hair growth in East Asia. Several companies produce shampoo containing an extract of ginger claimed to have anti-hair loss and hair growth promotion properties. However, there is no scientific evidence to back up these claims. This study was undertaken to measure 6-gingerol, the main active component of ginger, on hair shaft elongation in vitro and hair growth in vivo, and to investigate its effect on human dermal papilla cells (DPCs) in vivo and in vitro. 6-Gingerol suppressed hair growth in hair follicles in culture and the proliferation of cultured DPCs. The growth inhibition of DPCs by 6-gingerol in vitro may reflect a decrease in the Bcl-2/Bax ratio. Similar results were obtained in vivo. The results of this study showed that 6-gingerol does not have the ability to promote hair growth, on the contrary, can suppress human hair growth via its inhibitory and pro-apoptotic effects on DPCs in vitro, and can cause prolongation of telogen phase in vivo. Thus, 6-gingerol rather than being a hair growth stimulating drug, it is a potential hair growth suppressive drug; i.e. for hair removal.

  17. The development from kinetic coefficients of a predictive model for the growth of Eichhomia crassipes in the field. I. Generating kinetic coefficients for the model in greenhouse culture

    Directory of Open Access Journals (Sweden)

    C. F. Musil

    1984-12-01

    Full Text Available The kinetics of N- and P- limited growth of Eichhornia crassipes (Mart . Solms were investigated in greenhouse culture with the object of developing a model for predicting population sizes, yields, growth rates and frequencies and amounts of harvest, under varying conditions of nutrient loading and climate, to control both nutrient inputs and excessive growth in eutrophied aquatic systems. The kinetic coefficients, maximum specific growth rate (Umax, half saturation coefficient (Ks and yield coefficient (Yc were measured under N and P limitation in replicated batch culture experiments. Umax values and Ks concentrations derived under N limitation ranged from 5,37 to 8,86% d + and from 400 to 1 506 µg  N ℓ1respectively. Those derived under P limitation ranged from 4,51 to 10,89% d 1 and from 41 to 162 fig P ℓ1 respectively. Yc values (fresh mass basis determined ranged from 1 660 to 1 981 (87 to 98 dry mass basis for N and from 16 431 to 18 671 (867 to 980 dry mass basis for P. The reciprocals of Yc values (dry mass basis, expressed as percentages, adequately estimated the minimum limiting concentrations of N and P {% dry mass in the plant tissues. Kinetic coefficients determined are compared with those reported for algae. The experimental method used and results obtained are critically assessed.

  18. Photophysiological variability of microphytobenthic diatoms after growth in different types of culture conditions

    NARCIS (Netherlands)

    Forster, R.M.; Martin-Jézéquel, V.R.

    2005-01-01

    Microphytobenthic diatoms have great ecological importance in estuarine and coastal marine ecosystenis, yet many aspects of their physiology have not been investigated under controlled conditions. This work describes patterns in growth rates and photosynthesis in different types of culture for

  19. Growth behavior in plant cell cultures based on emissions detected by a multisensor array.

    Science.gov (United States)

    Komaraiah, Palle; Navratil, Marian; Carlsson, Maria; Jeffers, Paul; Brodelius, Maria; Brodelius, Peter E; Kieran, Patricia M; Mandenius, Carl-Fredrik

    2004-01-01

    The use of a multisensor array based on chemical gas sensors to monitor plant cell cultures is described. The multisensor array, also referred to as an electronic nose, consisted of 19 different metal oxide semiconductor sensors and one carbon dioxide sensor. The device was used to continuously monitor the off-gas from two plant cell suspension cultures, Morinda citrifolia and Nicotiana tabacum, cultivated under batch conditions. By analyzing the multiarray responses using two pattern recognition methods, principal component analysis and artificial neural networks, it was possible to monitor the course of the cultivations and, in turn, to predict (1) the biomass concentration in both systems and (2) the formation of the secondary metabolite, antraquinone, by M. citrifolia. The results identify the multisensor array method as a potentially useful analytical tool for monitoring plant process variables that are otherwise difficult to analyze on-line.

  20. Prunus dulcis, Batch

    African Journals Online (AJOL)

    STORAGESEVER

    2010-06-07

    Jun 7, 2010 ... almond (Prunus dulcis, Batch) genotypes as revealed by PCR analysis. Yavar Sharafi1*, Jafar Hajilou1, Seyed AbolGhasem Mohammadi2, Mohammad Reza Dadpour1 and Sadollah Eskandari3. 1Department of Horticulture, Faculty of Agriculture, University of Tabriz, Tabriz, 5166614766, Iran.

  1. Fish Culture Data - Characterization of Sexual Growth Dimorphism in Sablefish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sexual growth dimorphism (SGD) is a common phenomenon in nature. Numerous marine fishes exhibit SGD, with females often growing faster and attaining larger sizes...

  2. Growth of cultured human glioma tumour cells can be regulated with histamine and histamine antagonists.

    OpenAIRE

    Van der Ven, L. T.; Prinsen, I. M.; Jansen, G. H.; Roholl, P. J.; Defferrari, R.; Slater, R.; Den Otter, W.

    1993-01-01

    The 50% survival time for low grade astrocytomas is 50 months and for high grade astrocytomas it is 13 months, underlining the need for new therapies. Several reports show that in vivo histamine antagonists cause retardation of tumour growth in some animal models and prolonged survival in cancer patients. Therefore we have tested the growth modulating effects of histamine and histamine antagonists on human glioma cultures. Twelve freshly excised human gliomas were cultured and tested for thei...

  3. Small doses, big troubles: modeling growth dynamics of organisms affecting microalgal production cultures in closed photobioreactors.

    Science.gov (United States)

    Forehead, Hugh I; O'Kelly, Charles J

    2013-02-01

    The destruction of mass cultures of microalgae by biological contamination of culture medium is a pervasive and expensive problem, in industry and research. A mathematical model has been formulated that attempts to explain contaminant growth dynamics in closed photobioreactors (PBRs). The model simulates an initial growth phase without PBR dilution, followed by a production phase in which culture is intermittently removed. Contaminants can be introduced at any of these stages. The model shows how exponential growth from low initial inocula can lead to "explosive" growth in the population of contaminants, appearing days to weeks after inoculation. Principal influences are contaminant growth rate, PBR dilution rate, and the size of initial contaminant inoculum. Predictions corresponded closely with observed behavior of two contaminants, Uronema sp. and Neoparamoeba sp., found in operating PBRs. A simple, cheap and effective protocol was developed for short-term prediction of contamination in PBRs, using microscopy and archived samples. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Effects of auxins on growth and scopoletin accumulation in cell suspension cultures of Angelica archangelica L.

    Science.gov (United States)

    Siatka, T; Kasparová, M

    2008-01-01

    Scopoletin is a coumarin possessing many interesting biological effects, e.g., spasmolytic, anti-inflammatory, antimutagenic, antioxidant, antifungal, apoptosis-inducing, antiproliferative, acetylcholinesterase-inhibitory, and hypouricemic activities. Plant tissue cultures represent a promising alternative source of valuable plant-derived substances. A number of physical and chemical factors influence the cell growth and secondary metabolite biosynthesis in plant tissue cultures. The mechanism of their action is not completely understood. Besides other factors, plant growth regulators and light conditions play an important role. Effects of four auxins (2,4-dichlorophenoxyacetic acid, 2,4-D, alpha-naphthaleneacetic acid, NAA, beta-indoleacetic acid, IAA or beta-indolebutyric acid, IBA) at four concentrations (0.2, 2, 10 or 20 mg/l) on the culture growth and accumulation of scopoletin in the medium were tested in Angelica archangelica cell suspension cultures cultured under continuous light or in the dark. The highest culture growth was achieved with 2 mg/l 2,4-D, and 10 mg/l IAA. The best scopoletin levels were obtained with 0.2 mg/l 2,4-D, 2 mg/l 2,4-D, 10 mg/l NAA, and 20 mg/l IAA. The effects of light conditions were less marked than those of auxins and their concentrations in influencing both the cell growth and scopoletin accumulation in Angelica archangelica cell suspension cultures. The changes brought about by auxins were modified by light conditions.

  5. Influence of Culture Water Draw-off on Growth of the African Catfish ...

    African Journals Online (AJOL)

    An experiment was carried out over a period of 10 weeks to investigate the influence of culture water draw-‐off on growth and feed utilization of the African catfish. Two similar fish culture tanks (designated A and B) were stocked with juveniles of African catfish at 43 fish per m3. The fish were fed twice daily at 3 % body ...

  6. Exogenous growth factors do not affect the development of individually cultured murine embryos.

    Science.gov (United States)

    Herrick, Jason R; Greene-Ermisch, Alison F; Schoolcraft, William B; Krisher, Rebecca L

    2017-12-21

    The objective of this study was to evaluate the effects of multiple growth factors on the development of individually cultured murine embryos. Embryos produced by in vitro fertilization using in vitro (IVM) or in vivo (IVO) matured oocytes from three strains of mice (CF1, Swiss Webster, B6D2F1) were cultured individually (10 μl) in the absence (control) or presence of growth factors (paf, epidermal growth factor [EGF], insulin-like growth factor 1 [IGF-1], and granulocyte-macrophage colony-stimulating factor [GM-CSF]). Blastocyst formation, hatching, and blastocyst cell numbers (trophectoderm, inner cell mass, and total) were evaluated on days 4 and 5 of culture. Post-hatching development of CF1 IVO embryos was also evaluated in vitro and in vivo. The presence of growth factors did not improve the proportion of embryos forming blastocysts or initiating hatching for any of the types of embryos tested. The only significant (P embryos that formed blastocysts by day 5 in CF1 IVM embryos. The presence of growth factors also did not affect blastocyst cell numbers. For CF1 IVO embryos, the presence of growth factors during culture did not affect the proportion of embryos that attached to fibronectin-coated dishes, the size of the resulting outgrowths, or in vivo development following transfer. Combinations of paf, EGF, GM-CSF, and IGF-1 did not improve development of murine embryos cultured individually in a sequential medium containing a defined protein source.

  7. Growth performances and changes of macronutrient ion concentrations in the culture medium when Euglena gracilis was cultured with nitrified digestate.

    Science.gov (United States)

    Takemura, Kenji; Endo, Ryosuke; Shibuya, Toshio; Kitaya, Yoshiaki

    2017-09-01

    We investigated the possibility of using Euglena gracilis to convert digestate from methane fermentation of organic wastes into a medium for soilless crop culture. The growth of E. gracilis cultured with aqueous solutions containing filtrate of raw digestate at 1-30% (v/v) and nitrified digestate at 10-100% (v/v) was examined. Concentrations of plant macronutrient ions in nitrified digestate before and after culturing E. gracilis were also examined. Specific growth rates in aqueous solutions containing filtrate of raw digestate at 1-10% and nitrified digestate at 10-100% showed no significant differences, respectively (0.781 ± 0.031 d -1 and 0.925 ± 0.033 d -1 , mean ± standard error). The rates in the filtrate of nitrified digestate were significantly higher than those in the filtrate of raw digestate. Moreover, there were no significant differences between the concentrations of plant macronutrient ions other than [Formula: see text] in the filtrate of nitrified digestate before and after culturing E. gracilis. The concentration of [Formula: see text] decreased significantly by 10.5% of the initial concentration. As a result, the constituent ratio of plant macronutrient ions other than magnesium in the solution after culturing E. gracilis was similar to that in a standard nutrient solution for soilless culture.

  8. Single-walled carbon nanotubes: a nano-specific enhancer of cellular growth in LB culture

    International Nuclear Information System (INIS)

    Zhao Jinming; Yang Xiafeng; Zhao Yun; Huang Qing; Li Jiang; Lu Min

    2012-01-01

    We conducted a study to characterize the antimicrobial properties of SWNTs to B.subtilis in a saline solution or in a LB culture. Dimensions and the antibacterial ability of SWNTs in a saline solution were different from those in a LB culture. Transmission and scanning electron microscopes were used to characterize the SWNTs structure with and without LB culture. The antibacterial ability of SWNTs was affected by the environment of bacterial growth. The antibacterial mechanism of SWNTs was studied,too. (authors)

  9. Effect of mineral concentration of culture media without growth ...

    African Journals Online (AJOL)

    Owner

    rate of endogenous hormones. Key words: Atriplex halimus, in vitro culture, callogenesis, mineral elements. INTRODUCTION. Atriplex are plants adapted to the ... expected theoretical frequencies (fe). The value of X2 was calculated by means of the following formula (Schwartz, 1993): X2 = Σ(f0 – fe) 2 / fe . If all the observed ...

  10. Evaluation of culture media for growth and sporulation of ...

    African Journals Online (AJOL)

    Colocasia esculenta) in Cameroon and no information is yet available on its culture on common media. Six artificial media, V6 juice agar, V8 juice agar, V8m juice agar, potato dextrose agar, onion agar and taro leaf agar were assessed in vitro to ...

  11. Influence of culturing conditions on growth and sporulation of ...

    African Journals Online (AJOL)

    Drechslera hawaiiensis is responsible for foliar blight disease in Marsilea minuta L., a common weed of rice. Experiments were conducted for the determination of nutritional and climatic requirements of this pathogen. Five culture media viz. malt extract agar, potato dextrose agar, Richard's agar, water agar and Czapek Dox ...

  12. Growth and phenotypic characteristics of human nevus cells in culture.

    Science.gov (United States)

    Mancianti, M L; Herlyn, M; Weil, D; Jambrosic, J; Rodeck, U; Becker, D; Diamond, L; Clark, W H; Koprowski, H

    1988-02-01

    Nevus cells were isolated from the three cutaneous components, epidermis, basal layer, and dermis, of nonmalignant pigmented lesions and were cultured separately in the presence or absence of the phorbol ester 12-0-tetradecanoyl phorbol-13-acetate in medium that supports the rapid proliferation of melanocytic cells. The separation procedure used provided cultures that were essentially free from normal melanocytes (dermis) or fibroblasts (epidermis). In short term culture, nevus cells of all skin compartments expressed markers associated with differentiated melanocytes, such as presence of premelanosomes and melanosomes and elevated tyrosinase levels. Nevus cells also expressed melanoma-associated antigens, such as NGF-receptor, transferrin-related p97, proteoglycan, and HLA-DR as detected with monoclonal antibodies. After several subpassages, cells showed a decreased expression of melanoma-associated antigens, decreased tyrrosinase levels, and melanosomes could no longer be detected. Morphologically, these cells were similar to fibroblasts. The disappearance of melanoma-associated cell surface antigens was concomitant with the appearance of a melanocyte-associated 145 kd protein that might serve as a marker of fibroblast-like differentiation in nevus cells and normal melanocytes. Nevus cell cultures grown in the presence of 12-0-tetradecanoyl phorbol-13-acetate maintained a stable differentiated phenotype throughout their lifespan. As reported earlier, nevus cells in culture, irrespective of the presence or absence of 12-0-tetradecanoyl phorbol-13-acetate, have a finite lifespan in vitro, grow anchorage-independent in soft agar, but do not form tumors when xenografted to nude mice. These studies demonstrate that nevus cells isolated from the epidermal, basal layer, and dermal components of lesional skin can serve as models to characterize the initial steps of tumor progression in a human cell system.

  13. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    Science.gov (United States)

    He, Guo-qing; Kong, Qing; Chen, Qi-he; Ruan, Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that cultivation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB. PMID:16252341

  14. Cultural variation in early feeding pattern and maternal perceptions of infant growth

    NARCIS (Netherlands)

    van Eijsden, Manon; Meijers, Claire M. C.; Jansen, Jessica E.; De Kroon, Marlou L. A.; Vrijkotte, Tanja G. M.

    2015-01-01

    The perception of healthy growth and weight may differ between cultures, which could influence feeding practises and consequently affect the development of overweight. The present study examined ethnic variation in maternal perceptions of growth and their influence on feeding practises among Turkish

  15. A thin-layer liquid culture technique for the growth of Helicobacter pylori.

    Science.gov (United States)

    Joo, Jung-Soo; Park, Kyung-Chul; Song, Jae-Young; Kim, Dong-Hyun; Lee, Kyung-Ja; Kwon, Young-Cheol; Kim, Jung-Min; Kim, Kyung-Mi; Youn, Hee-Shang; Kang, Hyung-Lyun; Baik, Seung-Chul; Lee, Woo-Kon; Cho, Myung-Je; Rhee, Kwang-Ho

    2010-08-01

    Several attempts have been successful in liquid cultivation of Helicobaccter pylori. However, there is a need to improve the growth of H. pylori in liquid media in order to get affluent growth and a simple approach for examining bacterial properties. We introduce here a thin-layer liquid culture technique for the growth of H. pylori. A thin-layer liquid culture system was established by adding liquid media to a 90-mm diameter Petri dish. Optimal conditions for bacterial growth were investigated and then viability, growth curve, and released proteins were examined. Maximal growth of H. pylori was obtained by adding 3 mL of brucella broth supplemented with 10% horse to a Petri dish. H. pylori grew in both DMEM and RPMI-1640 supplemented with 10% fetal bovine serum and 0.5% yeast extract. Serum-free RPMI-1640 supported the growth of H. pylori when supplemented with dimethyl-beta-cyclodextrin (200 microg/mL) and 1% yeast extract. Under optimal growth, H. pylori grew exponentially for 28 hours, reaching a density of 3.4 OD(600) with a generation time of 3.3 hours. After 24 hours, cultures at a cell density of 1.0 OD(600) contained 1.3 +/- 0.1 x 10(9 )CFU/mL. gamma-Glutamyl transpeptidase, nuclease, superoxide dismutase, and urease were not detected in culture supernatants at 24 hours in thin-layer liquid culture, but were present at 48 hours, whereas alcohol dehydrogenase, alkylhydroperoxide reductase, catalase, and vacuolating cytotoxin were detected at 24 hours. Thin-layer liquid culture technique is feasible, and can serve as a versatile liquid culture technique for investigating bacterial properties of H. pylori.

  16. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...

  17. Growth, proline and ion accumulation in sugarcane callus cultures ...

    African Journals Online (AJOL)

    Calli obtained from two sugarcane cultivars (R570 and CP59-73) were exposed to different osmotic stress intensities followed by a period of stress relief. Relative rate growth, callus water content and changes in organic and inorganic solutes were determined at the end of stress and relief periods. After the stress period, ...

  18. Evaluation of conidia production and mycelial growth in solid culture ...

    African Journals Online (AJOL)

    FATIMAYALBERTO

    2012-10-02

    Oct 2, 2012 ... entomopathogenic fungi in Nicaragua. Manejo Integrado de Plagas. 63:95-103. Moore E (1996). Fundamentals of the fungi. Prentice Hall, New Jersey,. USA. pp. 574. Li DP, Holdom DG (1995). Effects of nutrients on colony Formation, growth, and sporulation of Metarhizium anisopliae (Deuteromycotina:.

  19. Effect of Growth Regulators and Culture Conditions on Direct Root ...

    African Journals Online (AJOL)

    Purpose: Rauwolfia serpentina (L.) Benth, from the family, Apocynaceae, is an important medicinal plant due to the alkaloid content of its root. The purpose of this study was to obtain roots directly from leaf explant using growth regulators. Methods: The leaf explant was inoculated on MS (Murashige and Skoog) medium ...

  20. Some growth factors stimulate cultured adult rabbit ventricular myocyte hypertrophy in the absence of mechanical loading

    Science.gov (United States)

    Decker, R. S.; Cook, M. G.; Behnke-Barclay, M.; Decker, M. L.

    1995-01-01

    Cultured adult rabbit cardiac myocytes treated with recombinant growth factors display enhanced rates of protein accumulation (ie, growth) in response to insulin and insulin-like growth factors (IGFs), but epidermal growth factor, acidic or basic fibroblast growth factor, and platelet-derived growth factor failed to increase contractile protein synthesis or growth of the heart cells. Insulin and IGF-1 increased growth rates by stimulating anabolic while simultaneously inhibiting catabolic pathways, whereas IGF-2 elevated growth modestly by apparently inhibiting lysosomal proteolysis. Neutralizing antibodies directed against either IGF-1 or IGF-2 or IGF binding protein 3 blocked protein accumulation. A monoclonal antibody directed against the IGF-1 receptor also inhibited changes in protein turnover provoked by recombinant human IGF-1 but not IGF-2. Of the other growth factors tested, only transforming growth factor-beta 1 increased the fractional rate of myosin heavy chain (MHC) synthesis, with beta-MHC synthesis being elevated and alpha-MHC synthesis being suppressed. However, the other growth factors were able to modestly stimulate the rate of DNA synthesis in this preparation. Bromodeoxyuridine labeling revealed that these growth factors increased DNA synthesis in myocytes and nonmyocytes alike, but the heart cells displayed neither karyokinesis or cytokinesis. In contrast, cocultures of cardiac myocytes and nonmyocytes and nonmyocyte-conditioned culture medium failed to enhance the rate of cardiac MHC synthesis or its accumulation, implying that quiescent heart cells do not respond to "conditioning" by cardiac nonmyocytes. These findings demonstrated that insulin and the IGFs promote passively loaded cultured adult rabbit heart cells to hypertrophy but suggest that other growth factors tested may be limited in this regard.

  1. The fed-batch principle for the molecular biology lab: controlled nutrient diets in ready-made media improve production of recombinant proteins in Escherichia coli.

    Science.gov (United States)

    Krause, Mirja; Neubauer, Antje; Neubauer, Peter

    2016-06-17

    While the nutrient limited fed-batch technology is the standard of the cultivation of microorganisms and production of heterologous proteins in industry, despite its advantages in view of metabolic control and high cell density growth, shaken batch cultures are still the standard for protein production and expression screening in molecular biology and biochemistry laboratories. This is due to the difficulty and expenses to apply a controlled continuous glucose feed to shaken cultures. New ready-made growth media, e.g. by biocatalytic release of glucose from a polymer, offer a simple solution for the application of the fed-batch principle in shaken plate and flask cultures. Their wider use has shown that the controlled diet not only provides a solution to obtain significantly higher cell yields, but also in many cases folding of the target protein is improved by the applied lower growth rates; i.e. final volumetric yields for the active protein can be a multiple of what is obtained in complex medium cultures. The combination of the conventional optimization approaches with new and easy applicable growth systems has revolutionized recombinant protein production in Escherichia coli in view of product yield, culture robustness as well as significantly increased cell densities. This technical development establishes the basis for successful miniaturization and parallelization which is now an important tool for synthetic biology and protein engineering approaches. This review provides an overview of the recent developments, results and applications of advanced growth systems which use a controlled glucose release as substrate supply.

  2. Opioid-dependent growth of glial cultures: Suppression of astrocyte DNA synthesis by met-enkephalin

    Energy Technology Data Exchange (ETDEWEB)

    Stiene-Martin, A.; Hauser, K.F. (Univ. of Kentucky, Lexington (USA))

    1990-01-01

    The action of met-enkephalin on the growth of astrocytes in mixed-glial cultures was examined. Primary, mixed-glial cultures were isolated from 1 day-old mouse cerebral hemispheres and continuously treated with either basal growth media, 1 {mu}M met-enkephalin, 1 {mu}M met-enkephalin plus the opioid antagonist naloxone, or naloxone alone. Absolute numbers of neural cells were counted in unstained preparations, while combined ({sup 3}H)-thymidine autoradiography and glial fibrillary acid protein (GFAP) immunocytochemistry was performed to identify specific changes in astrocytes. When compared to control and naloxone treated cultures, met-enkephalin caused a significant decrease in both total cell numbers, and in ({sup 3}H)-thymidine incorporation by GFAP-positive cells with flat morphology. These results indicate that met-enkephalin suppresses astrocyte growth in culture.

  3. Growth yields, polysaccharide production and energy conservation in chemostat cultures of Rhizobium trifolii.

    Science.gov (United States)

    de Hollander, J A; Bettenhaussen, C W; Stouthamer, A H

    1979-01-01

    Rhizobium trifolii was grown in a defined medium in chemostat cultures. Extracellular polysaccharide production was found in carbon-sufficient as well as in carbon-limited cultures. Extracellular polysaccharide production in carbon-limited cultures was strongly dependent on the growth rate. In mannitol-limited cultures, asparagine was always totally depleted from the culture medium. Only when the asparagine supply was not sufficient to meet the nitrogen need of the culture, ammonia assimilation took place. Excess organic nitrogen was excreted as ammonia. Whether ammonia assimilation or ammonia excretion took place was also dependent on the growth rate. Respiration-coupled proton translocation measurements showed the presence of three energy conserving sites in an electron transport chain which is branched. Assuming a H+/P ratio of 4, a P/O ratio of 2.33 was found. Growth yield calculations indicated a P/O ratio of approximately 2. Sulphate limitation in the chemostat culture resulted in a decrease in the efficiency of oxidative phosphorylation and in a less stringent coupling between growth and energy yielding processes.

  4. Growth and Cultural Characteristics of Ophiocordyceps longissima Collected in Korea

    OpenAIRE

    Sung, Gi-Ho; Shrestha, Bhushan; Han, Sang-Kuk; Sung, Jae-Mo

    2011-01-01

    We investigated the effect of nutritional and environmental factors on Ophiocordyceps longissima mycelial growth. The longest colony diameter was observed on Schizophyllum (mushroom) genetics complete medium plus yeast extract, Schizophyllum (mushroom) genetics minimal medium, and Sabouraud dextrose agar (SDA); however, malt-extract yeast-extract agar, SDA plus yeast extract, yeast-extract malt-extract peptone dextrose agar, SDA, oatmeal agar, and potato dextrose agar showed higher mycelia de...

  5. Culture media profoundly affect Candida albicans and Candida tropicalis growth, adhesion and biofilm development.

    Science.gov (United States)

    Weerasekera, Manjula M; Wijesinghe, Gayan K; Jayarathna, Thilini A; Gunasekara, Chinthika P; Fernando, Neluka; Kottegoda, Nilwala; Samaranayake, Lakshman P

    2016-11-01

    As there are sparse data on the impact of growth media on the phenomenon of biofilm development for Candida we evaluated the efficacy of three culture media on growth, adhesion and biofilm formation of two pathogenic yeasts, Candida albicans and Candida tropicalis. The planktonic phase yeast growth, either as monocultures or mixed cultures, in sabouraud dextrose broth (SDB), yeast nitrogen base (YNB), and RPMI 1640 was compared, and adhesion as well as biofilm formation were monitored using MTT and crystal violet (CV) assays and scanning electron microscopy. Planktonic cells of C. albicans, C. tropicalis and their 1:1 co-culture showed maximal growth in SDB. C. albicans/C. tropicalis adhesion was significantly facilitated in RPMI 1640 although the YNB elicited the maximum growth for C. tropicalis. Similarly, the biofilm growth was uniformly higher for both species in RPMI 1640, and C. tropicalis was the slower biofilm former in all three media. Scanning electron microscopy images tended to confirm the results of MTT and CV assay. Taken together, our data indicate that researchers should pay heed to the choice of laboratory culture media when comparing relative planktonic/biofilm growth of Candida. There is also a need for standardisation of biofilm development media so as to facilitate cross comparisons between laboratories.

  6. Effect of concentration of substrates and products on the growth of Klebsiella pneumoniae in chemostat cultures.

    Science.gov (United States)

    Rutgers, M; Balk, P A; van Dam, K

    1989-11-23

    Non-equilibrium thermodynamics (NET) can be used to describe microbial growth. In this description, the concentrations of products contribute to the driving forces of the metabolic processes (anabolism and catabolism). Thus, in contrast to the model of bacterial growth of Monod (Recherches sur la Croissance les Cultures Bactériennes (1942) Herman et Cie, Paris), it is predicted that the growth rate of a bacterial chemostat culture is, in principle, dependent on the concentration of the catabolic product (for instance HCO3-) during catabolite limitation and on the concentration of the anabolic product (for instance biomass) during anabolite limitation. In order to test this prediction, Klebsiella pneumoniae was grown in aerobic citrate-limited, glucose-limited or ammonia-limited chemostat cultures. Ammonia-limited cultures were considered to be essentially anabolite-limited, whereas citrate limitation was used as a representative for catabolite limitation. In ammonia-limited or in glucose-limited cultures it was found that the growth rate was independent of the biomass concentration present. In the NET description this means that the 'back' reaction (i.e., in the direction from biomass to substrates) is saturated with respect to biomass. On the other hand, in citrate-limited cultures, the steady-state concentration of citrate increased with the concentration of the catabolic product HCO3-. At relatively low concentrations of HCO3-, 'thermodynamic back-pressure' of growth (i.e., increase in product concentration was compensated by an increase in substrate concentration so that the driving force for growth remained almost constant) was demonstrated as predicted by the NET model. At concentrations above 40 mM, a kinetic (allosteric) effect of HCO3- was detected. This was concluded from a reduced growth yield on citrate, and from a significant decrease in the maximal growth rate and the maximal oxygen consumption rate after relief of the citrate limitation.

  7. Effect of Media Culture on Growth and Sucker Pandanus Plant

    Directory of Open Access Journals (Sweden)

    ali salehi sardoei

    2017-02-01

    Full Text Available Introduction: One factor that is of great importance to the cultivation of flowers and ornamental plants, is the media. Planting plants in containers as an important component of the nursery technology has grown. Compared with farm volume, growth media used for each plant greatly reduce plant growth that largely influence by the physical and chemical properties of growth media used. Therefore, good management of potted plants bed will cause the plants have good quality. A good growth media with optimal physical and biological properties, relatively inexpensive, stable and style enough to work should be available. The Burgers showed that composted green waste can be used as substrates for soilless cultivation and improve the water-holding capacity of soil. The garden has a range of materials including hardwood and softwood bark, leaves, soil, waste, sewage sludge and coconut (cocopeat that has been used as a seed bed. According to the economic issues and increasing moisture storage, palm peat substrates are primary material that can be prepared as a good growth medium for the producing's presented level Country. Peat moss is not applicable to all plants because of high cost and poor absorption characteristics like low pH and low water holding capacity . This study was conducted to investigate the possibility of replacing peat moss palm waste and the effect of it on growth characteristics were studied. Materials and Methods: The experimental design was completely randomized design with four replications of eight treatments. The compressed unit (block was supplied and commercial cocopeat was used because of reducing the cost of transportation. Before applying this material, the amount of water was added for opening up and voluminous and become it completely uniform.. In treatments containing sand + perlite, these four types volume ratio of 1:1 and mixed with sand + perlite were used. First, wooden cuttings of pandanus in a bed of sand rooted in the

  8. Nurturing mission. A case study of a hospital's cultural growth.

    Science.gov (United States)

    Kerr, F H

    1991-11-01

    Recognizing the need to enhance his hospital's fulfillment of its mission as a religious organization, the chief executive officer of Lutheran Hospital of Indiana, Inc., Fort Wayne, initiated a process to change the institution's corporate culture to reflect the mission. After assessing hospital managers' perceptions of the hospital's mission, a planning committee drafted a mission statement. The statement was condensed into an easily remembered motto, "Reach out and reflect God's love!" to guide employees' actions. The hospital expanded its position descriptions to include the facility's expectations for employee behavior that is consistent with the mission. An orientation program for new employees emphasizes incorporating the mission concepts of courtesy and compassion into all activities. To establish the mission firmly as part of the corporate culture, the hospital established three recognition programs and redesigned its pay plan to recognize performance that reflects the hospital's mission. Redecorating the drab facility has improved employees' attitudes toward their work environment. Five years into the change process, the hospital now has clear direction for strategic decisions, a more cooperative atmosphere, and increased admissions. The process continues, and assessment of the mission establishment process will lead to the initiation of continuous quality improvement concepts.

  9. Effects of basic fibroblast growth factor and insulin-like growth factor on cultured cartilage cells from skate Raja porasa

    Science.gov (United States)

    Fan, Tingjun; Jin, Lingyun; Wang, Xiaofeng

    2003-12-01

    Effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor II (IGF-II) on cartilage cells from proboscis of skate, Raja porasa Günther, were investigated in this study. The cartilage cells were cultured in 20% FBS-supplemented MEM medium at 24°C. Twelve hours after culture initiation, the cartilage cells were treated with bFGF and IGF-II at different concentration combinations. It was found that 20 ng/ml of bFGF or 80 ng/ml of IGF-II was enough to have obvious stimulating effect on the growth and division of skate cartilage cells. Test of bFGF and IGF-II together, revealed that 20 ng/ml of bFGF and 80 ng/ml of IGF-II together had the best stimulating effect on the growth and division of skate cartilage cells. The cartilage cells cultured could form a monolayer at day 7.

  10. Growth and steroidal saponin production in hairy root cultures of Solanum aculeatissimum.

    Science.gov (United States)

    Ikenaga, T; Oyama, T; Muranaka, T

    1995-04-01

    Hairy root cultures of Solanum aculeatissimum were established by trans-formation using Agrobacterium rhizogenes strain 15834. Root growth and production of steroidal saponin were investigated under various culture conditions. Transformed roots grew better in Gamborg's B5 medium containing 3 % sucrose under continuous light than in the dark. Also, the roots turned light green when cultured under continuous light. Green hairy roots produced aculeatiside A (6.71mg ·) L(-1) and aculeatiside B (6.39mg · L(-1)) after 8 weeks of culture, while no steroidal saponin was detected in hairy roots cultured in the dark. Of the three culture media tested, Gamborg's B5 medium was superior for growth and steroidal saponin production. Growth and steroidal saponin production were enhanced when 100μg · L(-1) auxin except for 2,4-D was added to the medium. The addition of 2,4-D inhibited growth. Production of steroidal saponin was highest with NAA. Transformed roots used in this experiment were confirmed that hairy roots examined contain both TL-DNA and TR-DNA region of Ri plasmid by PCR amplification analysis of DNA.

  11. Beta-type transforming growth factor specifies organizational behavior in vascular smooth muscle cell cultures.

    Science.gov (United States)

    Majack, R A

    1987-07-01

    In culture, vascular smooth muscle cells (SMC) grow in a "hill-and-valley" (multilayered) pattern of organization. We have studied the growth, behavioral organization, and biosynthetic phenotype of rat aortic SMC exposed to purified platelet-derived growth regulatory molecules. We show that multilayered growth is not a constitutive feature of cultured SMC, and that beta-type transforming growth factor (TGF-beta) is the primary determinant of multilayered growth and the hill-and-valley pattern of organization diagnostic for SMC in culture. TGF-beta inhibited, in a dose-dependent manner, the serum- or platelet-derived growth factor-mediated proliferation of these cells in two-dimensional culture, but only when cells were plated at subconfluent densities. The ability of TGF-beta to inhibit SMC growth was inversely correlated to plating cell density. When SMC were plated at monolayer density (5 X 10(4) cells/cm2) to allow maximal cell-to-cell contact, TGF-beta potentiated cell growth. This differential response of SMC to TGF-beta may contribute to the hill-and-valley pattern of organization. Unlike its effect on other cell types, TGF-beta did not enhance the synthesis of fibronectin or its incorporation into the extracellular matrix. However, the synthesis of a number of other secreted proteins was altered by TGF-beta treatment. SMC treated with TGF-beta for 4 or 8 h secreted markedly enhanced amounts of an Mr 38,000-D protein doublet whose synthesis is known to be increased by heparin (another inhibitor of SMC growth), suggesting metabolic similarities between heparin- and TGF-beta-mediated SMC growth inhibition. The data suggest that TGF-beta may play an important and complex regulatory role in SMC proliferation and organization during development and after vascular injury.

  12. Effects of sulfur and monensin concentrations on in vitro dry matter disappearance, hydrogen sulfide production, and volatile fatty acid concentrations in batch culture ruminal fermentations.

    Science.gov (United States)

    Smith, D R; Dilorenzo, N; Leibovich, J; May, M L; Quinn, M J; Homm, J W; Galyean, M L

    2010-04-01

    Effects of monensin (MON) and S on in vitro fermentation and H(2)S production were evaluated in 2 experiments. In Exp. 1, 2 ruminally cannulated steers were adapted (>14 d) to a 75% concentrate diet [steam-flaked corn (SFC)-based], and ruminal fluid was collected approximately 4 h after feeding. Substrate composed (DM basis) of 85.2% SFC, 9% alfalfa hay, 5% cottonseed meal, and 0.8% urea was added with ruminal fluid and buffer to sealed 125-mL serum bottles to allow for gas collection. A Na(2)SO(4) solution was added to yield S equivalent to 0.2, 0.4, and 0.8% of substrate DM, and MON was included at 0, 2, 4, and 6 mg/L of culture volume. Bottle head-space gas was analyzed for H(2)S. No MON (P = 0.29) or MON x S interaction (P = 0.41) effects were detected for H(2)S production. Increasing S linearly increased (P molar proportions of acetate, butyrate, and the acetate:propionate ratio (A:P), and linearly increased (P 21 d) to a 75% concentrate diet (SFC base) that contained 15% (DM basis) wet corn distillers grains plus solubles (WDGS) and MON at 22 mg/kg of DM. In vitro substrate DM was composed of 75.4% SFC, 15% WDGS, 9% alfalfa hay, and 0.6% urea, and S and MON concentrations were the same as in Exp. 1. No effects of MON (P = 0.93) or the MON x S interaction (P = 0.99) were noted for H(2)S production; however, increasing S linearly increased (P molar proportions of acetate, butyrate, and A:P and linearly increased (P molar proportions were evident with MON regardless of S concentration.

  13. Antipathogenic activity of probiotics against Salmonella Typhimurium and Clostridium difficile in anaerobic batch culture systems: is it due to synergies in probiotic mixtures or the specificity of single strains?

    Science.gov (United States)

    Tejero-Sariñena, Sandra; Barlow, Janine; Costabile, Adele; Gibson, Glenn R; Rowland, Ian

    2013-12-01

    Probiotics are currently being investigated for prevention of infections caused by enteric pathogens. The aim of this in vitro study was to evaluate the influence of three single probiotics: Lactobacillus casei NCIMB 30185 (PXN 37), Lactobacillus acidophilus NCIMB 30184 (PXN 35), Bifidobacterium breve NCIMB 30180 (PXN 25) and a probiotic mixture containing the above strains plus twelve other strains belonging to the Lactobacillus, Bifidobacterium, Lactococcus, Streptococcus and Bacillus genera on the survival of Salmonella Typhimurium and Clostridium difficile using pH-controlled anaerobic batch cultures containing mixed faecal bacteria. Changes in relevant bacterial groups and effects of probiotic addition on survival of the two pathogens were assessed over 24 h. Quantitative analysis of bacterial populations revealed that there was a significant increase in lactobacilli and/or bifidobacteria numbers, depending on probiotic addition, compared with the control (no added probiotic). There was also a significant reduction in S. Typhimurium and C. difficile numbers in the presence of certain probiotics compared with controls. Of the probiotic treatments, two single strains namely L. casei NCIMB 30185 (PXN 37), and B. breve NCIMB 30180 (PXN 25) were the most potent in reducing the numbers of S. Typhimurium and C. difficile. In addition, the supplementation with probiotics into the systems influenced some fermentations parameters. Acetate was found in the largest concentrations in all vessels and lactate and formate were generally detected in higher amounts in vessels with probiotic addition compared to controls. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Enhanced growth medium and method for culturing human mammary epithelial cells

    Science.gov (United States)

    Stampfer, Martha R.; Smith, Helene S.; Hackett, Adeline J.

    1983-01-01

    Methods are disclosed for isolating and culturing human mammary epithelial cells of both normal and malignant origin. Tissue samples are digested with a mixture including the enzymes collagenase and hyaluronidase to produce clumps of cells substantially free from stroma and other undesired cellular material. Growing the clumps of cells in mass culture in an enriched medium containing particular growth factors allows for active cell proliferation and subculture. Clonal culture having plating efficiencies of up to 40% or greater may be obtained using individual cells derived from the mass culture by plating the cells on appropriate substrates in the enriched media. The clonal growth of cells so obtained is suitable for a quantitative assessment of the cytotoxicity of particular treatment. An exemplary assay for assessing the cytotoxicity of the drug adriamycin is presented.

  15. The Cultural Divide: Exponential Growth in Classical 2D and Metabolic Equilibrium in 3D Environments

    DEFF Research Database (Denmark)

    Wrzesinski, Krzysztof; Rogowska-Wrzesinska, Adelina; Kanlaya, Rattiyaporn

    2014-01-01

    Introduction: Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures) and the other by a dynamic equilibrium (in 3D cultures). We have analyzed the proteome and cellular architecture at these two extremes and found that they are dram......Introduction: Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures) and the other by a dynamic equilibrium (in 3D cultures). We have analyzed the proteome and cellular architecture at these two extremes and found...... that they are dramatically different. Results: Structurally, actin organization is changed, microtubules are increased and keratins 8 and 18 decreased. Metabolically, glycolysis, fatty acid metabolism and the pentose phosphate shunt are increased while TCA cycle and oxidative phosphorylation is unchanged. Enzymes involved...

  16. Characterization of growth and Oryctes rhinoceros nudivirus production in attached cultures of the DSIR-HA-1179 coleopteran insect cell line.

    Science.gov (United States)

    Pushparajan, Charlotte; Claus, Juan Daniel; Marshall, Sean David Goldie; Visnovsky, Gabriel

    2013-12-01

    The DSIR-HA-1179 coleopteran cell line is a susceptible and permissive host to the Oryctes rhinoceros nudivirus (OrNV), which has been used as a biocontrol agent against the coconut rhinoceros beetle (Oryctes rhinoceros); a pest of palms in the Asia-Pacific region. However, little is known about growth and metabolism of this cell line, knowledge of which is necessary to develop an in vitro large-scale OrNV production process. The strong anchorage-dependent characteristics of the cell line, its particular fragility and its tendency to form dense clumps when manipulated, are the most likely reasons that have precluded further development of the cell line. In order to characterize DSIR-HA-1179 cells, there was first a need for a reliable technique to count the cells. A homogenous cell suspension suitable for enumeration could be produced by treatment with TrypLE Express™ with optimum mean time for cell release calculated as 30 min. The cell line was adapted to grow in four serum-supplemented culture media namely TC-100, IPL-41, Sf-900 II and Sf-900 III and cell growth, glucose consumption, lactate and ammonia production were assessed from static-batch cultures. The maximum viable cell density was reached in Sf-900 II (17.9 × 10(5) cells/ml), with the maximum specific growth rate observed in this culture medium as well (0.0074 h(-1)). Higher production of OrNV was observed in IPL-41 and TC-100 (4.1 × 10(7) TCID50/ml) than in cultures infected in Sf-900 III (2.0 × 10(7) TCID50/ml) and Sf-900 II (1.4 × 10(7) TCID50/ml). At the end of the growth period, glucose was completely consumed in cultures grown in TC-100, while remained in excess in the other three culture media. The cell line produced lactate and ammonia to very low levels in the TC-100 culture medium which is a promising aspect for its cultivation at large-scale.

  17. Phenotypic and growth characterization of human mesenchymal stem cells cultured from permanent and deciduous teeth

    Directory of Open Access Journals (Sweden)

    Revathi Shekar

    2012-01-01

    Conclusions: Permanent and deciduous teeth are both viable sources of stem cells. The permanent teeth were easier to culture because of a lower chance of contamination with oral microflora. The growth characteristics of the cells obtained from both these sources were similar. However, there was a difference in the ratio of fibroblastoid cells to epithelioid cells between the cultures obtained from the permanent and deciduous teeth.

  18. Effects of Yeast Polysaccharide on Growth and Flavonoid Accumulation in Fagopyrum tataricum Sprout Cultures

    OpenAIRE

    Zhao, Gang; Zhao, Jianglin; Peng, Lianxin; Zou, Liang; Wang, Jingbo; Zhong, Lingyun; Xiang, Dabing

    2012-01-01

    The purpose of this study was to investigate the effects of yeast polysaccharide (YPS) on growth and flavonoid accumulation in sprout cultures of Fagopyrum tataricum (tartary buckwheat). Without obvious change in the appearance of the sprouts, the exogenous YPS notably stimulated the production of functional metabolites in F. tataricum sprouts, and the stimulation effect was concentration-dependent. With 400 mg/L of YPS applied to the sprout cultures ...

  19. New approaches for growth improvement in pejerrey Odontesthes bonariensis (Valenciennes, 1835 culture (Atherinomorpha: Atherinopsidae

    Directory of Open Access Journals (Sweden)

    Patricio J. Solimano

    Full Text Available The pejerrey is the most important recreational species in shallow temperate lakes and reservoirs of Argentina and the attempts to develop its culture have started a century ago. A common constraint of pejerrey aquaculture is its poor growth under traditional intensive rearing techniques. The aim of this study was to evaluate the possibility to achieve and maintain high growth rates of pejerrey throughout the rearing process by semi-intensive culture method . Four floating cages were installed in La Salada de Monasterio Lake and each one was stocked with 300 juveniles (10.22 ±0.38cm; 6.52 ±0.82g. From January through March all fish were exposed to natural zooplankton as food source, whereas from April to September two cages were supplied daily with artificial food. The fish exposed to artificial supplementary diets exhibited significantly higher growth (17.5 ±0.98cm; 41.05 ±8.55g than those in the control cages (15.02 ±0cm ; 23.5 ±0.84g, and exceeded the known values in pejerrey culture. The results suggest that the species potential growth is not fully achieved by common intensive methods and it can be improved by semi-intensive techniques. Accordingly a better understanding of the species nutritional requirements is needed to improve growth rates and enhance pejerrey culture.

  20. Effects of Growth Regulators on the Induction of Anthocyanin Synthesis in Carrot Suspension Cultures

    OpenAIRE

    Yoshihiro, Ozeki; Atsushi, Komamine; Department of Botany, Faculty of Science, The University of Tokyo:(Present)Department of Biology, College of Arts and Sciences, The University of Tokyo; Department of Botany, Faculty of Science, The University of Tokyo:(Present)Biological Institute, Faculty of Science, Tohoku University

    1986-01-01

    The effects of plant growth regulators were investigated on anthocyanin synthesis induced by removing auxin from carrot suspension cultures. Of the auxins tested, 2,4-D showed the strongest inhibiting effect on anthocyanin synthesis and had the strongest promoting effect on undifferentiated growth. When 2,4-D was added to anthocyanin synthesizing cells, in which cell division had ceased, anthocyanin synthesis was repressed immediately, accumulated anthocyanin disappeared and cell division res...

  1. Effect of Spiritist "passe" (Spiritual healing) on growth of bacterial cultures.

    Science.gov (United States)

    Lucchetti, Giancarlo; de Oliveira, Renata Ferreira; Gonçalves, Juliane Piasseschi de Bernardin; Ueda, Suely Mitoi Ykko; Mimica, Lycia Mara Jenne; Lucchetti, Alessandra Lamas Granero

    2013-12-01

    Biofield therapies are approaches that harness energy fields to influence the human body. These therapies encompass Reiki, Qigong, Therapeutic Touch, Johrei and Spiritist "passe", among others. The aim of this study was to evaluate bacterial growth in two groups of cultures subjected to biofield therapy (Spiritist "passe" and laying on of hands (LOH)) in four situations (no intention, intention to inhibit bacterial growth, intention to promote growth, and influence of a negative factor) and compare them with a "no LOH/no treatment" group. Bacterial cultures (Escherichia coli ATCC) were randomized and allocated into three groups: Spiritist "passe", "LOH", and "no LOH". Bacterial growth was assessed using the McFarland Nephelometer Scale. A One-way ANOVA was performed to determine group differences in bacterial growth at 48h, and at 1 week after each situation. A total of 11 Spiritist "passe" healers, 10 LOH laymen and "no LOH" tubes were assessed. Under the intention to inhibit bacterial growth condition, statistically significant differences were found between the Spiritist "passe" and "no LOH" Groups (p=0.002 after 48h, and p=0.008 after one week) and also between the Spiritist "passe" and "LOH" Groups (p=0.005 after 48h, and p=0.009 after one week). No statistically significant difference was detected for the other situations tested (no intention, intention to promote growth and influence of a negative factor). We concluded that Spiritist "passe" effectively inhibited growth in bacterial cultures compared to LOH with intention or no LOH. Further studies comparing different intentions and types of LOH in cultures of cells and microorganisms are warranted. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Foliar fertilizations with boron and growth regulators on lettuce (Lactuca sativa L.) cv floresta culture

    International Nuclear Information System (INIS)

    Masunaga, S.I.; Chueire, F.B.; Teixeira, N.T.

    1989-01-01

    The experiment was realized to verify the possibility of applying Boron as foliar fertilization with growth regulators: indol acetic acid, giberellic acid, ethephon and cycocel. The other objective was to compare the foliar and soil fertilization, with Boron, on the lettuce culture. The results showed that there wasn't difference of production between the treatments. Meanwhile the application of growth regulator modified the Boron grade in the leaves. (author) [pt

  3. Effects of mixed substrates on growth and vitamin production by ...

    African Journals Online (AJOL)

    The effects of mixed carbon sources on growth and production of vitamins E and A by Euglena gracilis cells were investigated in batch culture. The cells were grown mixotrophically in glucose (G), ethanol (E) and a mixture of glucose and ethanol (EG). Cell growth was measured by counting the cell number with microscope, ...

  4. Effect of growth media modifications on cell biomass and ...

    African Journals Online (AJOL)

    The growth media dependency of S. frigidimarina in terms of its growth behavior in response to modifications made to the media as well as its potential to produce PUFAs was evaluated. S. frigidimarina was cultured in conventional shake-flasks and controlled bioreactors with a batch-type procedure using different media ...

  5. Transition from exponential to linear photoautotrophic growth changes the physiology of Synechocystis sp. PCC 6803

    NARCIS (Netherlands)

    Schuurmans, R.M.; Matthijs, J.C.P.; Hellingwerf, K.J.

    Phototrophic microorganisms like cyanobacteria show growth curves in batch culture that differ from the corresponding growth curves of chemotrophic bacteria. Instead of the usual three phases, i.e., lag-, log-, and stationary phase, phototrophs display four distinct phases. The extra growth phase is

  6. Differential Expression of Extracellular Matrix and Growth Factors by Embryoid Bodies in Hydrodynamic and Static Cultures

    Science.gov (United States)

    Fridley, Krista M.; Nair, Rekha

    2014-01-01

    During development, cell fate specification and tissue development are orchestrated by the sequential presentation of soluble growth factors (GF) and extracellular matrix (ECM) molecules. Similarly, differentiation of stem cells in vitro relies upon the temporal presence of extracellular cues within the microenvironment. Hydrodynamic culture systems are not limited by volume restrictions and therefore offer several practical advantages for scalability over static cultures; however, hydrodynamic cultures expose cells to physical parameters not present in static culture, such as fluid shear stress and mass transfer through convective forces. In this study, the differences between static and hydrodynamic culture conditions on the expression of ECM and GF molecules during the differentiation of mouse embryonic stem cells were examined at both the gene and protein level. The expression of ECM and GF genes exhibited an early decrease in static cultures based on heat map and hierarchical clustering analysis and a relative delayed increase in hydrodynamic cultures. Although the temporal patterns of specific ECM and GF protein expression were comparable between static and hydrodynamic cultures, several notable differences in the magnitudes of expression were observed at similar time points. These results describe the establishment of an analytical framework that can be used to examine the expression patterns of ECM and GF molecules expressed by pluripotent stem cells undergoing differentiation as 3D multicellular aggregates under different culture conditions, and suggest that physical parameters of stem cell microenvironments can alter endogenous ECM and GF expression profiles that may, in turn, influence cell fate decisions. PMID:25423310

  7. Simple control of fed-batch processes for recombinant protein production with E. coli.

    Science.gov (United States)

    Schaepe, Sebastian; Kuprijanov, Artur; Aehle, Mathias; Simutis, Rimvydas; Lübbert, Andreas

    2011-09-01

    A very simple but effective process control technique is proposed that leads to a high batch-to-batch reproducibility with respect to biomass concentration as well as the specific biomass growth rate profiles in E. coli fermentations performed during recombinant protein production. It makes use of the well-established temperature controllers in currently used fermenters, but takes its information from the difference between the controlled culture temperature T (cult) and the temperature T (coolin) of the coolant fed to the fermenter's cooling jacket as adjusted by the fermenter temperature controller. For process control purposes this measured difference is corrected regarding stirrer influences and cumulated before it is used as a new process control variable. As a spin-off of this control, it becomes possible to estimate online the oxygen mass transfer rates and the corresponding k(L)a values during the real cultivation process. © Springer Science+Business Media B.V. 2011

  8. Unusal pattern of product inhibition: batch acetic acid fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Bar, R.; Gainer, J.L.; Kirwan, D.J.

    1987-04-20

    The limited tolerance of microorganisms to their metabolic products results in inhibited growth and product formation. The relationship between the specific growth rate, micro, and the concentration of an inhibitory product has been described by a number of mathematical models. In most cases, micro was found to be inversely proportional to the product concentration and invariably the rate of substrate utilization followed the same pattern. In this communication, the authors report a rather unusual case in which the formation rate of a product, acetic acid, increased with a decreasing growth rate of the microorganism, Acetobacter aceti. Apparently, a similar behavior was mentioned in a review report with respect to Clostridium thermocellum in a batch culture but was not published in the freely circulating literature. The fermentation of ethanol to acetic acid, C/sub 2/H/sub 5/OH + O/sub 2/ = CH/sub 3/COOH + H/sub 2/O is clearly one of the oldest known fermentations. Because of its association with the commercial production of vinegar it has been a subject of extensive but rather technically oriented studies. Suprisingly, the uncommon uncoupling between the inhibited microbial growth and the product formation appears to have been unnoticed. 13 references.

  9. Progressing batch hydrolysis process

    Science.gov (United States)

    Wright, John D.

    1986-01-01

    A progressive batch hydrolysis process for producing sugar from a lignocellulosic feedstock, comprising passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feedstock to glucose; cooling said dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, then feeding said dilute acid stream serially through a plurality of prehydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose; and cooling the dilute acid stream containing glucose after it exits the last prehydrolysis reactor.

  10. Metabolic and energetic aspects of the growth of Clostridium butyricum on glucose in chemostat culture.

    Science.gov (United States)

    Crabbendam, P M; Neijssel, O M; Tempest, D W

    1985-09-01

    The influence of a number of environmental parameters on the fermentation of glucose, and on the energetics of growth of Clostridium butyricum in chemostat culture, have been studied. With cultures that were continuously sparged with nitrogen gas, glucose was fermented primarily to acetate and butyrate with a fixed stoichiometry. Thus, irrespective of the growth rate, input glucose concentration, specific nutrient limitation and, within limits, the culture pH value, the acetate/butyrate molar ratio in the culture extracellular fluids was uniformly 0.74 +/- 0.07. Thus, the efficiency with which ATP was generated from glucose catabolism also was constant at 3.27 +/- 0.02 mol ATP/mol glucose fermented. However, the rate of glucose fermentation at a fixed growth rate, and hence the rate of ATP generation, varied markedly under some conditions, leading to changes in the Y glucose and YATP values. In general, glucose-sufficient cultures expressed lower yield values than a corresponding glucose-limited culture, and this was particularly marked with a potassium-limited culture. However, with a glucose-limited culture increasing the input glucose concentration above 40 g glucose X 1(-1) also led to a significant decrease in the yield values that could be partially reversed by increasing the sparging rate of the nitrogen gas. Finally glucose-limited cultures immediately expressed an increased rate of glucose fermentation when relieved of their growth limitation. Since the rate of cell synthesis did not increase instantaneously, again the yield values with respect to glucose consumed and ATP generated transiently decreased. Two conditions were found to effect a change in the fermentation pattern with a lowering of the acetate/butyrate molar ratio. First, a significant decrease in this ratio was observed when a glucose-limited culture was not sparged with nitrogen gas; and second, a substantial (and progressive) decrease was observed to follow addition of increasing amounts of

  11. Reactive oxygen species are involved in BMP-induced dendritic growth in cultured rat sympathetic neurons.

    Science.gov (United States)

    Chandrasekaran, Vidya; Lea, Charlotte; Sosa, Jose Carlo; Higgins, Dennis; Lein, Pamela J

    2015-07-01

    Previous studies have shown that bone morphogenetic proteins (BMPs) promote dendritic growth in sympathetic neurons; however, the downstream signaling molecules that mediate the dendrite promoting activity of BMPs are not well characterized. Here we test the hypothesis that reactive oxygen species (ROS)-mediated signaling links BMP receptor activation to dendritic growth. In cultured rat sympathetic neurons, exposure to any of the three mechanistically distinct antioxidants, diphenylene iodinium (DPI), nordihydroguaiaretic acid (NGA) or desferroxamine (DFO), blocked de novo BMP-induced dendritic growth. Addition of DPI to cultures previously induced with BMP to extend dendrites caused dendritic retraction while DFO and NGA prevented further growth of dendrites. The inhibition of the dendrite promoting activity of BMPs by antioxidants was concentration-dependent and occurred without altering axonal growth or neuronal cell survival. Antioxidant treatment did not block BMP activation of SMAD 1,5 as determined by nuclear localization of these SMADs. While BMP treatment did not cause a detectable increase in intracellular ROS in cultured sympathetic neurons as assessed using fluorescent indicator dyes, BMP treatment increased the oxygen consumption rate in cultured sympathetic neurons as determined using the Seahorse XF24 Analyzer, suggesting increased mitochondrial activity. In addition, BMPs upregulated expression of NADPH oxidase 2 (NOX2) and either pharmacological inhibition or siRNA knockdown of NOX2 significantly decreased BMP-7 induced dendritic growth. Collectively, these data support the hypothesis that ROS are involved in the downstream signaling events that mediate BMP7-induced dendritic growth in sympathetic neurons, and suggest that ROS-mediated signaling positively modulates dendritic complexity in peripheral neurons. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Growth kinetics and physiological behavior of co-cultures of Saccharomyces cerevisiae and Kluyveromyces lactis, fermenting carob sugars extracted with whey.

    Science.gov (United States)

    Rodrigues, B; Lima-Costa, M E; Constantino, A; Raposo, S; Felizardo, C; Gonçalves, D; Fernandes, T; Dionísio, L; Peinado, J M

    2016-10-01

    Alcoholic fermentation of carob waste sugars (sucrose, glucose and fructose) extracted with cheese whey, by co-cultures of Saccharomyces cerevisiae and Kluyveromyces lactis has been analyzed. Growth and fermentation of S. cerevisiae in the carob-whey medium showed an inhibition of about 30% in comparison with water-extracted carob. The inhibition of K. lactis on carob-whey was greater (70%) when compared with the whey medium alone, due to osmolarity problems. Oxygen availability was a very important factor for K. lactis, influencing its fermentation performance. When K. lactis was grown alone on carob-whey medium, lactose was always consumed first, and glucose and fructose were consumed afterwards, only at high aeration conditions. In co-culture with S. cerevisiae, K. lactis was completely inhibited and, at low aeration, died after 3 days; at high aeration this culture could survive but growth and lactose fermentation were only recovered after S. cerevisiae became stationary. To overcome the osmolarity and K. lactis' oxygen problems, the medium had to be diluted and a sequential fermentative process was designed in a STR-3l reactor. K. lactis was inoculated first and, with low aeration (0.13vvm), consumed all the lactose in 48h. Then S. cerevisiae was inoculated, consuming the total of the carob sugars, and producing ethanol in a fed-batch regime. The established co-culture with K. lactis increased S. cerevisiae ethanol tolerance. This fermentation process produced ethanol with good efficiency (80g/l final concentration and a conversion factor of 0.4g ethanol/g sugar), eliminating all the sugars of the mixed waste. These efficient fermentative results pointed to a new joint treatment of agro-industrial wastes which may be implemented successfully, with economic and environmental sustainability for a bioethanol industrial proposal. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Effect Of Culture Media On The Plant Growth And Establishment Of ...

    African Journals Online (AJOL)

    An experiment was conducted to assess the regeneration of vegetative propagule of Myrianthus arboreous in different growing media. The objective of this study was to assess the response of stem cuttings to different culture media for plant take and survival. The growth variables taken increase with time. Topsoil produced ...

  14. Modification of growth conditions by mm-waves of wood-decaying mushrooms cultures

    International Nuclear Information System (INIS)

    Avagyan, I.A.

    2016-01-01

    Basidial macromycetes are not only value food, but can be used as source of such biological active compounds as the genistein, β -glucans, glioxal-oxidase et al. In this work we used different frequencies of extremely high frequency of electromagnetic irradiation (EHF EMI) with the aim of obtaining mushroom cultures with increased fermentative activity by the modulation of its growth conditions during growth on the peptone media. We investigated the influence of the non-thermal extremely high frequency electromagnetic waves in the interval of 45-53 GHz on β-glucosidase activities of two species of wood-decaying mushroom. In this study we examined the most popular edible wood-decaying mushroom Pleurotus ostreatus, which is wide-spread in the forests and commercial mushroom Lentinula edodes, under influence of such an abiotic factor as the extremely high frequency waves in the interval of 45 GHz - 53 GHz during 20 and 40 min on the 7th day of mycelial culture's growth. After the treatment of cultures we continued their growth and on the 3th day we examined the influence of these waves on fermentative activity of mycelial extracts. The some conditions of such treatment led to significant rising of β-glucosidase activities in the extracts of mycelial cultures

  15. Effects of ash leachates on growth and development of Armillaria mellea in culture.

    Science.gov (United States)

    Jimmy L. Reaves; Charles G. III Shaw; Robert E. Martin; John E. Mayfield

    1984-01-01

    Ash leachates from recently burned litter in a ponderosa pine forest in central Oregon were tested for their effects on growth and development of Armillaria mellea in culture. Two isolates were used: one from an infected western hemlock and the other from an infected ponderosa pine tree. Colonies developing from agar discs containing mycelia of the...

  16. The role of DNA amplification and cultural growth in complicated acute appendicitis

    Directory of Open Access Journals (Sweden)

    Francesca Tocchioni

    2016-09-01

    Full Text Available Bacterial growth of peritoneal fluid specimens obtained during surgical procedures for acute appendicitis may be useful to optimize further antibiotic therapy in complicated cases. DNA amplification represents a fast technique to detect microbial sequences. We aimed to compare the potential of DNA amplification versus traditional bacterial growth culture highlighting advantages and drawbacks in a surgical setting. Peritoneal fluid specimens were collected during surgery from 36 children who underwent appendectomy between May and December 2012. Real-time polymerase chain reaction (RT-PCR and cultures were performed on each sample. RT-PCR showed an amplification of 16S in 18/36 samples, Escherichia coli (in 7 cases, Pseudomonas aeruginosa (3, Fusobacterium necrophorum (3, Adenovirus (2, E.coli (1, Klebsiella pneumoniae (1, Serratia marcescens/Enterobacter cloacae (1. Bacterial growth was instead observed only in four patients (3 E.coli and 1 P.aeruginosa and Bacteroides ovatus. Preoperative C-reactive protein and inflammation degree, the most reliable indicators of bacterial translocation, were elevated as expected. DNA amplification was a quick and useful method to detect pathogens and it was even more valuable in detecting aggressive pathogens such as anaerobes, difficult to preserve in biological cultures; its drawbacks were the lack of biological growths and of antibiograms. In our pilot study RT-PCR and cultures did not influence the way patients were treated.

  17. Religious Orders and Growth through Cultural Change in Pre-Industrial England

    DEFF Research Database (Denmark)

    Andersen, Thomas Barnebeck; Bentzen, Jeanet; Dalgaard, Carl-Johan

    We advance the hypothesis that cultural values such as high work ethic and thrift, “the Protestant ethic” according to Max Weber, may have been diffused long before the Reformation, thereby importantly affecting the pre-industrial growth record. The source of pre-Reformation Protestant ethic...

  18. Growth of Crassostrea gasar cultured in marine and estuary environments in Brazilian waters

    Directory of Open Access Journals (Sweden)

    Gustavo Ruschel Lopes

    2013-08-01

    Full Text Available The objective of this work was to evaluate the growth of the mangrove oyster Crassostrea gasar cultured in marine and estuarine environments. Oysters were cultured for 11 months in a longline system in two study sites - São Francisco do Sul and Florianópolis -, in the state of Santa Catarina, Southern Brazil. Water chlorophyll-α concentration, temperature, and salinity were measured weekly. The oysters were measured monthly (shell size and weight gain to assess growth. At the end of the culture period, the average wet flesh weight, dry flesh weight, and shell weight were determined, as well as the distribution of oysters per size class. Six nonlinear models (logistic, exponential, Gompertz, Brody, Richards, and Von Bertalanffy were adjusted to the oyster growth data set. Final mean shell sizes were higher in São Francisco do Sul than in Florianópolis. In addition, oysters cultured in São Francisco do Sul were more uniformly distributed in the four size classes than those cultured in Florianópolis. The highest average values of wet flesh weight and shell weight were observed in São Francisco do Sul, whereas dry flesh weight did not differ between the sites. The estuary environment is more promising for the cultivation of oysters.

  19. Effect of a Bacterial Grass Culture on the Plant Growth and Disease Control in Tomato

    Directory of Open Access Journals (Sweden)

    Yong Seong Lee

    2017-12-01

    Full Text Available This study aimed to investigate the plant growth-promoting and biocontrol potential of a grass culture with Paenibacillus ehimensis KWN8 on tomato. For this experiment, treatments of a chemical fertilizer (F, a bacterial grass culture (G, a 1/3 volume of G plus 2/3 F (GF, and F plus a synthetic fungicide (FSf were applied to tomato leaves and roots. The result showed that the severity of Alternariasolani and Botrytiscinerea symptoms were significantly reduced after the application of the bacterial grass culture (G and GF and FSf. In addition, root mortality in G and GF was lower compared to F. Tomato plants treated with G or GF had better vegetative growth and yield compared to F. Application of G affected the fungal and bacterial populations in the soil. In conclusion, treatment with a bacterial grass culture decreased disease severity and increased tomato growth parameters. However, there were no statistically significant correlations between disease occurrence and tomato yields. This experiment presents the possibility to manage diseases of tomato in an environmentally friendly manner and to also increase the yield of tomato by using a grass culture broth containing P. ehimensis KWN38.

  20. Batch-batch stable microbial community in the traditional fermentation process of huyumei broad bean pastes.

    Science.gov (United States)

    Zhu, Linjiang; Fan, Zihao; Kuai, Hui; Li, Qi

    2017-09-01

    During natural fermentation processes, a characteristic microbial community structure (MCS) is naturally formed, and it is interesting to know about its batch-batch stability. This issue was explored in a traditional semi-solid-state fermentation process of huyumei, a Chinese broad bean paste product. The results showed that this MCS mainly contained four aerobic Bacillus species (8 log CFU per g), including B. subtilis, B. amyloliquefaciens, B. methylotrophicus, and B. tequilensis, and the facultative anaerobe B. cereus with a low concentration (4 log CFU per g), besides a very small amount of the yeast Zygosaccharomyces rouxii (2 log CFU per g). The dynamic change of the MCS in the brine fermentation process showed that the abundance of dominant species varied within a small range, and in the beginning of process the growth of lactic acid bacteria was inhibited and Staphylococcus spp. lost its viability. Also, the MCS and its dynamic change were proved to be highly reproducible among seven batches of fermentation. Therefore, the MCS naturally and stably forms between different batches of the traditional semi-solid-state fermentation of huyumei. Revealing microbial community structure and its batch-batch stability is helpful for understanding the mechanisms of community formation and flavour production in a traditional fermentation. This issue in a traditional semi-solid-state fermentation of huyumei broad bean paste was firstly explored. This fermentation process was revealed to be dominated by a high concentration of four aerobic species of Bacillus, a low concentration of B. cereus and a small amount of Zygosaccharomyces rouxii. Lactic acid bacteria and Staphylococcus spp. lost its viability at the beginning of fermentation. Such the community structure was proved to be highly reproducible among seven batches. © 2017 The Society for Applied Microbiology.

  1. Influence of the Culture Media and the Organic Matter in the Growth of Paxillus ammoniavirescens (Contu & Dessi).

    Science.gov (United States)

    Cagigal, Elena Fernández-Miranda; Sánchez, Abelardo Casares

    2017-09-01

    The genus Paxillus is characterized by the difficulty of species identification, which results in reproducibility problems, as well as the need for large quantities of fungal inoculum. In particular, studies of Paxillus ammoniavirescens have reported divergent results in the in vitro growth while little is known of its capacity to degrade organic matter. For all the above, and assuming that this variability could be due to an inappropriate culture media, the aim of this study was to analyse growth in different culture media (MMN, MS, and 1/2 MS) and in the case of MMN in presence/absence of two types of organic matter (fresh litter and senescence litter) to probe the saprophytic ability of P. ammoniavirescens . We also evaluated the effects of pH changes in the culture media. Growth kinetics was assessed by weekly quantification of the area of growth in solid culture media over 5 wk, calculating the growth curves and inflection points of each culture media. In addition, final biomass after 5 wk in the different culture media was calculated. Results showed that best culture media are MS and 1/2 MS. Moreover, an improvement in growth in culture media containing decomposing fall litter was observed, leading to confirm differences in the culture media of this species with others of the same genus. Further, we established that all growth media suffered a significant acidification after fungal growth.

  2. Insulin growth factors regulate the mitotic cycle in cultured rat sympathetic neuroblasts

    International Nuclear Information System (INIS)

    DiCicco-Bloom, E.; Black, I.B.

    1988-01-01

    While neuronal mitosis is uniquely restricted to early development, the underlying regulation remains to be defined. The authors have now developed a dissociated, embryonic sympathetic neuron culture system that uses fully defined medium in which cells enter the mitotic cycle. The cultured cells expressed two neuronal traits, tyrosine hydroxylase and the neuron-specific 160-kDa neurofilament subunit protein, but were devoid of glial fibrillary acidic protein, a marker for non-myelin-forming Schwann cells in ganglia. Approximately one-third of the tyrosine hydroxylase-positive cells synthesized DNA in culture, specifically incorporating [ 3 H]thymidine into their nuclei. They used this system to define factors regulating the mitotic cycle in sympathetic neuroblasts. Members of the insulin family of growth factors, including insulin and insulin-like growth factors I and II, regulated DNA synthesis in the presumptive neuroblasts. Insulin more than doubled the proportion of tyrosine hydroxylase-positive cells entering the mitotic cycle, as indicated by autoradiography of [ 3 H]thymidine incorporation into nuclei. Scintillation spectrometry was an even more sensitive index of DNA synthesis. In contrast, the trophic protein nerve growth factor exhibited no mitogenic effect, suggesting that the mitogenic action of insulin growth factors is highly specific. The observations are discussed in the context of the detection of insulin growth factors and receptors in the developing brain

  3. Effects of outdoor cultures on the growth and lipid production of Phaeodactylum tricornutum using closed photobioreactors.

    Science.gov (United States)

    Santos-Ballardo, David U; Rendón-Unceta, María Del Carmen; Rossi, Sergio; Vázquez-Gómez, Rosa; Hernández-Verdugo, Sergio; Valdez-Ortiz, Angel

    2016-08-01

    One of the principal challenges for large scale production of microalgae is the high costs of biomass production. Aiming for minimize this problem, microalgal biodiesel production should focus on outdoors cultures, using available solar light and allowing lower energy cost process. Testing species that proved to be common and easy to culture may be a good approach in this process. The present work reports indoor-outdoor cultures of Phaeodactylum tricornutum using different bioreactors types, using cell growth, biochemical composition, and the profiles of the fatty acids produced as the parameters to test the optimization processes. The results show that the use of outdoor cultures is a good choice to obtain P. tricornutum biomass with a good potential for biodiesel production. The microalgae produced reached better growth efficiency, major lipid content and showed an increment in the percentage of saturated fatty acids (required on the biodiesel production) respect indoor cultures. These results are important to show the relevance of using outdoor cultures as a way to improve the efficiency and the energetic balance of the biodiesel production with P. tricornutum algae.

  4. Development of a serum-free defined system employing growth factors for preantral follicle culture.

    Science.gov (United States)

    Park, Young Hyun; Gong, Seung Pyo; Kim, Hwa Young; Kim, Gil Ah; Choi, Jun Hee; Ahn, Ji Yeon; Lim, Jeong Mook

    2013-09-01

    This study was conducted to evaluate if mouse preantral follicles can yield developmentally competent oocytes following culture in serum-free, defined medium. Donor follicles were obtained from 14-day-old B6CBAF1 mice, and cultured in α-MEM-Glutamax medium. The replacement of fetal bovine serum with knockout serum replacement (KSR) did not significantly reduce follicle growth or oocyte maturation in vitro, although it significantly reduced the development of oocytes after activation. Regardless of the replacement medium, follicle growth was not influenced by the addition of leukemia inhibitory factor (LIF). The addition of 100 ng/ml stem cell factor (SCF) to the KSR-supplemented serum-free medium significantly stimulated follicle development, which further improved blastocyst formation after oocyte activation. On Day 3 of culture, a significant increase in Bmp7 expression was detected in the SCF-containing medium compared with the serum-containing medium, whereas Gdf9 and Amh were increased in the serum-containing medium. A significant increase in estradiol production was detected under serum-free conditions, but minimal progesterone secretion was detected throughout the culture period. In conclusion, serum-free media can be used to optimize ovarian follicle cultures, and the addition of SCF is beneficial for deriving developmentally competent oocytes through follicle culture. Copyright © 2013 Wiley Periodicals, Inc.

  5. Optimal Culture Conditions for Mycelial Growth and Exo-polymer Production of Ganoderma applanatum.

    Science.gov (United States)

    Jeong, Yong-Tae; Jeong, Sang-Chul; Yang, Byung-Keun; Islam, Rezuanul; Song, Chi-Hyun

    2009-06-01

    The effect of fermentation parameters and medium composition on the simultaneous mycelial growth and exo-polymer production from submerged cultures of Ganoderma applanatum was investigated in shake-flask cultures. The optimum initial pH for mycelial growth and exo-polymer production was 5.0 and 6.0, respectively. The optimum temperature was 25℃ and the optimum inoculum content was 3.0% (v/v). The optimal carbon and nitrogen sources were glucose and corn steep powder, respectively. After 12 days fermentation under these conditions, the highest mycelial growth was 18.0 g/l and the highest exo-polymer production was 3.9 g/l.

  6. Gaseous CO2 signal initiates growth of butyric-acid-producing Clostridium butyricum in both pure culture and mixed cultures with Lactobacillus brevis.

    Science.gov (United States)

    Hakalehto, Elias; Hänninen, Osmo

    2012-07-01

    Microbial strains produce numerous volatile substances in the anaerobic conditions of the human intestines. The availability of CO(2) is known to be a prerequisite for bacterial growth in general. In experiments with anaerobic Lactobacillus brevis and Clostridium butyricum bacteria in the Portable Microbial Enrichment Unit (PMEU) it was shown that these strains interact; this interaction being mediated by CO(2) emission. CO(2) promoted clostridial growth in pure cultures and mixed cultures with lactobacilli. The growth of C. butyricum in pure cultures was much delayed or did not start at all without CO(2) from outside. Conversely, the onset of growth was provoked by a short (15 min) CO(2) burst. In mixed cultures the presence of lactobacilli in equal numbers speeded up the onset of clostridial growth by 10 h. If C. butyricum cultures designated as PMEU 1, 2, and 3 in cultivation syringes were chained by connecting the gas flow thereby allowing the volatiles of the preceding syringe culture to bubble to the next one, the growth started in 20, 10, or 6 h, respectively. This effect of gaseous emissions from other cultures speeding up the bacterial growth initiation was abolished if the gas was passed through sodium hydroxide to remove the CO(2). The positive contribution of lactobacilli to the growth of butyric-acid-producing clostridia documented in this simulation experiment with PMEU has in vivo implications and indicates molecular communication between the species. CO(2) is a necessary signal for the growth of clostridia, and lactobacilli can promote clostridial growth in mixed cultures where both bacteria grow well with mutual benefit.

  7. Development of culture medium using extruded bean as a nitrogen source for yeast growth.

    Science.gov (United States)

    Batista, Karla A; Bataus, Luiz Artur M; Campos, Ivan T N; Fernandes, Kátia F

    2013-03-01

    In this study extruded bean was used as a nitrogen source substitute in culture medium formulation. A 3-factor simplex-lattice mixture design was used to establish better growth conditions. Completely substituted medium resulted in 43% of increase in the growth of Saccharomyces cerevisiae. Mixtures containing 1% extruded bean and 1% yeast extract, or 1% extruded bean and 1% peptone presented growths of 76-79% higher than the commercial YPD medium for S. cerevisiae. Pichia pastoris (GS115) growth was enhanced by 20% using a completely substituted medium. The protein expression patterns in P. pastoris (GS115) remained unchanged when growth was conducted in a medium containing extruded bean as unique nitrogen source. The total amount of recombinant protein expressed in extruded bean medium was 88.5% higher than in control expression medium. These results evidenced that extruded bean can be successfully used as a substitute of peptone and yeast extract in culture media for S. cerevisiae's and P. pastoris' (GS115) growth. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Differences in stationary-phase cells of a commercial Saccharomyces cerevisiae wine yeast grown in aerobic and microaerophilic batch cultures assessed by electric particle analysis, light diffraction and flow cytometry.

    Science.gov (United States)

    Portell, X; Ginovart, M; Carbó, R; Vives-Rego, J

    2011-01-01

    We applied electric particle analysis, light diffraction and flow cytometry to obtain information on the morphological changes during the stationary phase of Saccharomyces cerevisiae. The reported analyses of S. cerevisiae populations were obtained under two different conditions, aerobic and microaerophilic, at 27°C. The samples analysed were taken at between 20 and 50 h from the beginning of culture. To assist in the interpretation of the observed distributions a complexity index was used. The aerobically grown culture reached significantly greater cell density. Under these conditions, the cell density experienced a much lower reduction (3%) compared with the microaerophilic conditions (30%). Under aerobic conditions, the mean cell size determined by both electric particle analysis and light diffraction was lower and remained similar throughout the experiment. Under microaerophilic conditions, the mean cell size determined by electric particle analysis decreased slightly as the culture progressed through the stationary phase. Forward and side scatter distributions revealed two cell subpopulations under both growth conditions. However, in the aerobic growing culture the two subpopulations were more separated and hence easier to distinguish. The distributions obtained with the three experimental techniques were analysed using the complexity index. This analysis suggested that a complexity index is a good descriptor of the changes that take place in a yeast population in the stationary phase, and that it aids in the discussion and understanding of the implications of these distributions obtained by these experimental techniques.

  9. Bacterial growth and DOC consumption in a tropical coastal lagoon

    OpenAIRE

    Farjalla,V. F.; Enrich-Prast,A.; Esteves,F. A.; Cimbleris,A. C. P.

    2006-01-01

    The aims of this research were to determine the main limiting nutrient to bacterial growth in Imboassica lagoon, southeastern Brazil, to estimate the percentage of dissolved organic carbon (DOC) available for bacterial growth, and to determine the bacterial growth efficiency (BGE) of natural assemblages. Bacterial growth and DOC consumption were determined in batch culture experiments, in which water samples were supplemented with nitrogen and phosphorus together or separately, or incubated w...

  10. Cracking Streptococcus thermophilus to stimulate the growth of the probiotic Lactobacillus casei in co-culture.

    Science.gov (United States)

    Ma, Chengjie; Ma, Aimin; Gong, Guangyu; Liu, Zhenmin; Wu, Zhengjun; Guo, Benheng; Chen, Zhengjun

    2015-10-01

    Lactobacillus casei, a probiotic, and Streptococcus thermophilus, a fast acidifying lactic acid bacterial strain, are both used in the food industry. The aim of this study was to investigate the interaction between L. casei and S. thermophilus in the presence or absence of S. thermophilus-specific bacteriophage during milk fermentation. The acidification capability of L. casei co-cultured with S. thermophilus was significantly higher than that observed for L. casei or S. thermophilus cultured alone. However, the probiotic content (i.e., L. casei cell viability) was low. The fastest acidification and the highest viable L. casei cell count were observed in co-cultures of L. casei and S. thermophilus with S. thermophilus phage. In these co-cultures, S. thermophilus compensated for the slow acid production of L. casei in the early exponential growth phase. Thereafter, phage-induced lysis of the S. thermophilus cells eliminated the competition for nutrients, allowing L. casei to grow well. Additionally, the ruptured S. thermophilus cells released intracellular factors, which further promoted the growth and function of the probiotic bacteria. Crude cellular extract isolated from S. thermophilus also significantly accelerated the growth and propagation of L. casei, supporting the stimulatory role of the phage on this micro-ecosystem. Copyright © 2015. Published by Elsevier B.V.

  11. Effects of Wnt-10b on hair shaft growth in hair follicle cultures

    International Nuclear Information System (INIS)

    Ouji, Yukiteru; Yoshikawa, Masahide; Moriya, Kei; Ishizaka, Shigeaki

    2007-01-01

    Wnts are deeply involved in the proliferation and differentiation of skin epithelial cells. We previously reported the differentiation of cultured primary skin epithelial cells toward hair shaft and inner root sheath (IRS) of the hair follicle via β-catenin stabilization caused by Wnt-10b, however, the effects of Wnt-10b on cultured hair follicles have not been reported. In the present study, we examined the effects of Wnt-10b on shaft growth using organ cultures of whisker hair follicles in serum-free conditions. No hair shaft growth was observed in the absence of Wnt-10b, whereas its addition to the culture promoted elongation of the hair shaft, intensive incorporation of BrdU in matrix cells flanking the dermal papilla (DP), and β-catenin stabilization in DP and IRS cells. These results suggest a promoting effect of Wnt-10b on hair shaft growth that is involved with stimulation of the DP via Wnt-10b/β-catenin signalling, proliferation of matrix cells next to the DP, and differentiation of IRS cells by Wnt-10b

  12. Laminin enhances the growth of human neural stem cells in defined culture media

    Directory of Open Access Journals (Sweden)

    Lathia Justin D

    2008-07-01

    Full Text Available Abstract Background Human neural stem cells (hNSC have the potential to provide novel cell-based therapies for neurodegenerative conditions such as multiple sclerosis and Parkinson's disease. In order to realise this goal, protocols need to be developed that allow for large quantities of hNSC to be cultured efficiently. As such, it is important to identify factors which enhance the growth of hNSC. In vivo, stem cells reside in distinct microenvironments or niches that are responsible for the maintenance of stem cell populations. A common feature of niches is the presence of the extracellular matrix molecule, laminin. Therefore, this study investigated the effect of exogenous laminin on hNSC growth. Results To measure hNSC growth, we established culture conditions using B27-supplemented medium that enable neurospheres to grow from human neural cells plated at clonal densities. Limiting dilution assays confirmed that neurospheres were derived from single cells at these densities. Laminin was found to increase hNSC numbers as measured by this neurosphere formation. The effect of laminin was to augment the proliferation/survival of the hNSC, rather than promoting the undifferentiated state. In agreement, apoptosis was reduced in dissociated neurospheres by laminin in an integrin β1-dependent manner. Conclusion The addition of laminin to the culture medium enhances the growth of hNSC, and may therefore aid their large-scale production.

  13. Inhibitory Activity of Yokukansankachimpihange against Nerve Growth Factor-Induced Neurite Growth in Cultured Rat Dorsal Root Ganglion Neurons

    Directory of Open Access Journals (Sweden)

    Chiaki Murayama

    2015-08-01

    Full Text Available Chronic pruritus is a major and distressing symptom of many cutaneous diseases, however, the treatment remains a challenge in the clinic. The traditional Chinese-Japanese medicine (Kampo medicine is a conservative and increasingly popular approach to treat chronic pruritus for both patients and medical providers. Yokukansankachimpihange (YKH, a Kampo formula has been demonstrated to be effective in the treatment of itching of atopic dermatitis in Japan although its pharmacological mechanism is unknown clearly. In an attempt to clarify its pharmacological actions, in this study, we focused on the inhibitory activity of YKH against neurite growth induced with nerve growth factor (NGF in cultured rat dorsal root ganglion (DRG neurons because epidermal hyperinnervation is deeply related to itch sensitization. YKH showed approximately 200-fold inhibitory activity against NGF-induced neurite growth than that of neurotropin (positive control, a drug used clinically for treatment of chronic pruritus. Moreover, it also found that Uncaria hook, Bupleurum root and their chemical constituents rhynchophylline, hirsutine, and saikosaponin a, d showed inhibitory activities against NGF-induced neurite growth, suggesting they should mainly contribute to the inhibitory activity of YKH. Further study on the effects of YKH against epidermal nerve density in “itch-scratch” animal models is under investigation.

  14. Effect of culture conditions on the growth of biomass Yarrowia lipolytica - producing protein feed

    Directory of Open Access Journals (Sweden)

    O. S. Korneeva

    2016-01-01

    Full Text Available Fodder yeast is highly valuable protein-vitamin products. Protein digestibility by yeast and amino acid content, superior proteins of animal origin. Fodder yeast protein digested in animals by 95 %. The biological value of yeast protein is determined by the presence of a significant amount of essential amino acids. Moreover, yeast cells contain many vitamins microelement and a significant amount of fat, in which the predominant unsaturated fatty acid. Currently, fodder yeast successfully used in livestock and poultry, so the demand for them is increasing every year. For the production of fodder yeast using a yeast having the necessary technological properties: the ability of rapid growth in aerobic conditions to form protein, amino acids and vitamins, resistant crop production, the development of resistance to foreign microorganisms. Intensive education yeast biomass contributes to a number of conditions, including pH, temperature and aeration of the culture occupy an important place. The main criterion for comparison and selection of a culture medium for this is the speed of its growth and ability to assimilate all of the nutrients with high economic factor. It depends on the performance of the enterprise, energy consumption and other technical - economic performance. The effect of pH of the medium on the biomass accumulation of yeast Yarrowia lipolytica. Found that at pH 5,2 - 5,5 observed maximum growth rate of the yeast cells. The effect of temperature on the accumulation of yeast biomass. The temperature of the culture medium determines the intensity of metabolism in cells. It was found that the optimal growth temperature of the culture Yarrowia lipolytica is 33 0C. The effect of aeration on the growth rate of yeast cells. Tro-established that the maximum increase of biomass was obtained with the aeration of 70 cm3 /cm3hrs.

  15. [The action of epidermal growth factor on the development of cultured striatum cells].

    Science.gov (United States)

    Castillo-Díaz, L; Castellano-Benítez, O; Soto-Alonso, J; Rosillo-Martí, J C; de la Cuétara-Bernal, K

    1997-10-01

    Epidermic growth factor (EGF) has a neurotrophic mitogenic effect on different cell populations in the nervous system. This is modulated by the stage of development and microenvironment of the cells. In this paper we describe the action of EGF on embryonic striatum cells of a culture system dissociated from neurons and glias. The cell culture is prepared from 16-17 day rat embryos. In the system used, the cell population was cultured for 20-24 hours in a medium containing serum. This medium was later replaced by a mixture of specific nutrients and treated for 6 days with 20 mg/ml of EGF. The substitution of serum during the initial period of development led to an appreciable reduction in the living cells in the treated cultures and in the controls. The surviving cells were mainly cellular precursors, taking into account their morphological characteristics and capacity for proliferation. The effect of EGF was seen in an increase in the number of cells and was shown to be a stimulus to the proliferation of neuronal and astrocyte precursors. The specific activity of choline acetyl-transferases determined in the cultures at 16 days showed differentiation of a cholinergic neurons subpopulation, which responded to treatment with nerve growth factor with an increase in the activity of this enzyme.

  16. Time dependent physiological characterization of yeast oxidative stress response and growth modulation of protein kinase/phosphatase mutants

    DEFF Research Database (Denmark)

    Altintas, Ali; Workman, Christopher

    2013-01-01

    .25, 0.50 and 1.0 mM). Understanding the growth physiology of S. cerevisiae allows us to estimate the link between genotype and stress-response phenotype. Growth physiology parameters, such as growth rate, diauxic shift times, stress-induced stasis times, were measured in fermentative batch cultures...

  17. Development and validation of a minimal growth medium for recycling Chlorella vulgaris culture.

    Science.gov (United States)

    Hadj-Romdhane, F; Jaouen, P; Pruvost, J; Grizeau, D; Van Vooren, G; Bourseau, P

    2012-11-01

    When microalgae culture medium is recycled, ions (e.g. Na(+), K(+), Ca(2+)) that were not assimilated by the microalgae accumulate in the medium. Therefore, a growth medium (HAMGM) was developed that included ions that were more easily assimilated by Chlorella vulgaris, such as ammonium one (NH(4)(+)). Recycling performance was studied by carrying out 8-week continuous cultivation of C. vulgaris with recycled HAMGM medium. No loss of biomass productivity was observed compared to culture in a conventional medium, and accumulation of ions over time was negligible. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. The cultural divide: exponential growth in classical 2D and metabolic equilibrium in 3D environments

    DEFF Research Database (Denmark)

    Wrzesinski, Krzysztof; Rogowska-Wrzesinska, Adelina; Borkowski, Kamil

    2014-01-01

    Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures) and the other by a dynamic equilibrium (in 3D cultures). We have analysed the proteome and cellular architecture at these two extremes and found that they are dramatically...... different. Ultrastructurally, actin organization is changed, microtubules are increased and keratins 8 and 18 decreased. Metabolically, glycolysis, fatty acid metabolism and the pentose phosphate cycle are increased while Krebs cycle and oxidative phosphorylation is unchanged. Enzymes involved...

  19. The cultural divide: exponential growth in classical 2D and metabolic equilibrium in 3D environments

    DEFF Research Database (Denmark)

    Carvalho, Vasco Botelho

    Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures) and the other by a dynamic equilibrium (in 3D cultures). We have analysed the proteome and cellular architecture at these two extremes and found that they are dramatically...... different. Ultrastructurally, actin organization is changed, microtubules are increased and keratins 8 and 18 decreased. Metabolically, glycolysis, fatty acid metabolism and the pentose phosphate cycle are increased while Krebs cycle and oxidative phosphorylation is unchanged. Enzymes involved...

  20. Primary neuron culture for nerve growth and axon guidance studies in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Zheyan Chen

    Full Text Available Zebrafish (Danio rerio is a widely used model organism in genetics and developmental biology research. Genetic screens have proven useful for studying embryonic development of the nervous system in vivo, but in vitro studies utilizing zebrafish have been limited. Here, we introduce a robust zebrafish primary neuron culture system for functional nerve growth and guidance assays. Distinct classes of central nervous system neurons from the spinal cord, hindbrain, forebrain, and retina from wild type zebrafish, and fluorescent motor neurons from transgenic reporter zebrafish lines, were dissociated and plated onto various biological and synthetic substrates to optimize conditions for axon outgrowth. Time-lapse microscopy revealed dynamically moving growth cones at the tips of extending axons. The mean rate of axon extension in vitro was 21.4±1.2 µm hr(-1 s.e.m. for spinal cord neurons, which corresponds to the typical ∼0.5 mm day(-1 growth rate of nerves in vivo. Fluorescence labeling and confocal microscopy demonstrated that bundled microtubules project along axons to the growth cone central domain, with filamentous actin enriched in the growth cone peripheral domain. Importantly, the growth cone surface membrane expresses receptors for chemotropic factors, as detected by immunofluorescence microscopy. Live-cell functional assays of axon extension and directional guidance demonstrated mammalian brain-derived neurotrophic factor (BDNF-dependent stimulation of outgrowth and growth cone chemoattraction, whereas mammalian myelin-associated glycoprotein inhibited outgrowth. High-resolution live-cell Ca(2+-imaging revealed local elevation of cytoplasmic Ca(2+ concentration in the growth cone induced by BDNF application. Moreover, BDNF-induced axon outgrowth, but not basal outgrowth, was blocked by treatments to suppress cytoplasmic Ca(2+ signals. Thus, this primary neuron culture model system may be useful for studies of neuronal development

  1. Vision Marker-Based In Situ Examination of Bacterial Growth in Liquid Culture Media.

    Science.gov (United States)

    Kim, Kyukwang; Choi, Duckyu; Lim, Hwijoon; Kim, Hyeongkeun; Jeon, Jessie S

    2016-12-18

    The detection of bacterial growth in liquid media is an essential process in determining antibiotic susceptibility or the level of bacterial presence for clinical or research purposes. We have developed a system, which enables simplified and automated detection using a camera and a striped pattern marker. The quantification of bacterial growth is possible as the bacterial growth in the culturing vessel blurs the marker image, which is placed on the back of the vessel, and the blurring results in a decrease in the high-frequency spectrum region of the marker image. The experiment results show that the FFT (fast Fourier transform)-based growth detection method is robust to the variations in the type of bacterial carrier and vessels ranging from the culture tubes to the microfluidic devices. Moreover, the automated incubator and image acquisition system are developed to be used as a comprehensive in situ detection system. We expect that this result can be applied in the automation of biological experiments, such as the Antibiotics Susceptibility Test or toxicity measurement. Furthermore, the simple framework of the proposed growth measurement method may be further utilized as an effective and convenient method for building point-of-care devices for developing countries.

  2. The effect of sebocytes cultured from nevus sebaceus on hair growth.

    Science.gov (United States)

    Lee, Weon Ju; Cha, Hyun Wuk; Lim, Hyun Jung; Lee, Seok-Jong; Kim, Do Won

    2012-10-01

    Sebaceous glands are known to affect hair growth. Nevus sebaceus, a sebaceous gland hamartomas, presents as hairless patches. In this study, cultures of nevus sebaceus sebocytes (NSS) and normal scalp hair follicle sebocytes (NS) were used in performance of microarray, RT-PCR, western blot assay and immunofluorescence staining. NSS- and NS-conditioned media were also added to the culture of outer root sheath cells (ORSCs), dermal papilla cells (DPCs) or normal scalp hair follicle sebocytes. Results of this study showed a decrease in the survival rate of ORSCs and DPCs and hair growth in the NSS-conditioned medium-treated group, compared with the control and NS-conditioned medium-treated groups. An increase in expression of fibroblast growth factor (FGF)-5, Dickkopf-1 and inflammatory cytokines and a decrease in expression of Wnt10b and Lef1 were observed. In conclusion, NSS showed an increase in expression of hair growth-suppressing bioactive factors, including FGF-5, and a decrease in expression of hair growth-stimulating factors. © 2012 John Wiley & Sons A/S.

  3. Growth hormone receptors in cultured adipocytes: a model to study receptor regulation.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1986-09-01

    Acutely isolated rat adipocytes have been maintained in primary culture for several days and the effects of culture on the kinetics of 125I-human growth hormone (hGH) binding to adipocytes have been determined. A marked increase (500-1000%) in specific binding of 125I-hGH was observed over the first 3 days of culture--acutely isolated adipocytes (5.5 +/- 1.4%, mean +/- SE, n = 47) compared to 3-day cultured adipocytes (48 +/- 7%, mean +/- SE, n = 8). Specific binding of 125I-hGH to both acutely isolated and cultured adipocytes was dependent on incubation time and temperature (equilibrium being reached in 1 h at 37 degrees C and 2 h at 22 degrees C). Binding was reversible (t1/2 approximately 1.5 h). Scatchard analysis revealed linear plots and showed that the increase in binding during culture was due to an increase in the number of receptors per cell (approximately 20 000 to approximately 170 000) with little or no change in binding affinity (Ka approximately 1 X 10(9) M-1). Cycloheximide inhibited the increase in binding sites during culture suggesting a requirement for de novo protein synthesis. Addition of unlabelled hGH to the culture medium resulted in a marked down-regulation of the GH receptor by 2 days. The GH-induced decrease in receptor number was to due to receptor occupancy by exogenously added GH. The studies to date indicate that the cultured rat adipocyte should provide a useful model for a comprehensive study of the cellular mechanisms and dynamics of GH receptor regulation.

  4. Primary Culture of Canine Growth Plate Chondrocytes as a Model of Biomineralization

    OpenAIRE

    Ryuji, HOSOKAWA; Kenji, KIKUZAKI; Daisuke, CHIBA; Yasumasa, AKAGAWA; Department of Removable Prosthodontics, Hiroshima University School of Dentistry; Department of Removable Prosthodontics, Hiroshima University School of Dentistry; Department of Removable Prosthodontics, Hiroshima University School of Dentistry; Department of Removable Prosthodontics, Hiroshima University School of Dentistry

    1999-01-01

    This study investigated the mineralization process in primary cultures of dog growth plate chondrocytes as a model of biomineralization. Chondrocytes were isolated from the growth plates of ribs of 1-week-old dogs. The chondrocytes were maintained at extremely high density (5x10^4 cells/well) in collagen-coated 96-well dishes in a-MEM supplemented with 10% fetal bovine serum and 50 μg/ml ascorbic acid. Mineralization was initiated between days 20 and 24; however, the addition of fibroblast gr...

  5. Growth of Saccharomycopsis fibuliger and Candida utilis in mixed culture on apple processing wastes

    Energy Technology Data Exchange (ETDEWEB)

    Fellows, P.J.; Worgan, J.T.

    1987-07-01

    Sequential cultures of the yeasts Saccharomycopsis fibuliger and Candida utilis were grown on selected wastes from the processing of apples. Effluent from cider manufacture supported the growth of 45.4 g cells/100 g substrate and C. utilis formed 96% of the viable cells in the harvested biomass. Whole, unripe apples yielded 44 g cells/100 g substrate with a reduction in the substrate viscosity of 84%. C. utilis formed 56% of the viable cells in the harvested biomass. Effluent from pectin manufacture contained a substantial proportion of reducing compounds and supported the growth of C. utilis without prehydrolysis by S. fibuliger, to yield 33 g cells/100 g substrate. (Refs. 26).

  6. Axenization and optimization of in vitro growth of clonal cultures of Tetratrichomonas gallinarum and Trichomonas gallinae.

    Science.gov (United States)

    Amin, Aziza; Neubauer, Claudia; Liebhart, Dieter; Grabensteiner, Elvira; Hess, Michael

    2010-02-01

    A rapid and simple procedure was established to obtain clonal axenic cultures of Tetratrichomonas gallinarum and Trichomonas gallinae and to optimize their in vitro growth conditions. Medium 199 was used for axenization of two genetically different clones of T. gallinarum and T. gallinae. Six different media were used to optimize the growth behaviour of axenically grown parasites: Medium 199, TYM, TYI-S-33, Hollander fluid (HF), Trichomonas vaginalis (TV) and modified TV media. The highest cell yields for both axenic clones of T. gallinarum were obtained in modified TV medium without antibiotics. The maximum numbers of trophozoites of T. gallinae were obtained in an optimized HF medium. This study demonstrated that axenic cultures for T. gallinarum and T. gallinae could be obtained avoiding the migration technique through a V-tube. Following axenization and optimization, both clones of T. gallinarum and T. gallinae could be propagated both aerobically and anaerobically. Copyright 2009 Elsevier Inc. All rights reserved.

  7. Process for inhibiting the growth of a culture of lactic acid bacteria, and optionally lysing the bacterial cells, and uses of the resulting lysed culture

    NARCIS (Netherlands)

    Nauta, Arjen; Venema, Gerard; Kok, Jan; Ledeboer, Aat M.

    1995-01-01

    The invention provides a process for inhibiting the growth of a culture of lactic acid bacteria, or a product containing such culture e.g. a cheese product, in which in the cells of the lactic acid bacteria a holin obtainable from bacteriophages of Gram-positive bacteria, esp. from bacteriophages of

  8. Technology, Economic Growth, And The State: American Political Culture And Economy, 1870-2000

    OpenAIRE

    SALVATORE, Nick

    2015-01-01

    The guiding force of American national consciousness and socio-economic growth resides, as Alexis de Tocqueville noted long ago, in a deeply grounded, complex proclamation of the rights of the individual. Well before the American Revolution proved successful in 1781, the public culture of the American colonies found expression in the language, symbols, and imperatives of the Protestant Reformation, with its stark focus on the individual's responsibility to seek and serve his God. In the ...

  9. Technology, Economic Growth, And The State: American Political Culture And Economy, 1870-2000

    OpenAIRE

    SALVATORE, Nick

    2008-01-01

    The guiding force of American national consciousness and socio-economic growth resides, as Alexis de Tocqueville noted long ago, in a deeply grounded, complex proclamation of the rights of the individual. Well before the American Revolution proved successful in 1781, the public culture of the American colonies found expression in the language, symbols, and imperatives of the Protestant Reformation, with its stark focus on the individual's responsibility to seek and serve his God. In the ninet...

  10. Nanoparticle growth and surface chemistry changes in cell-conditioned culture medium

    OpenAIRE

    Kendall, Michaela; Hodges, Nikolas J.; Whitwell, Harry; Tyrrell, Jess; Cangul, Hakan

    2015-01-01

    When biomolecules attach to engineered nanoparticle (ENP) surfaces, they confer the particles with a new biological identity. Physical format may also radically alter, changing ENP stability and agglomeration state within seconds. In order to measure which biomolecules are associated with early ENP growth, we studied ENPs in conditioned medium from A549 cell culture, using dynamic light scattering (DLS) and linear trap quadrupole electron transfer dissociation mass spectrometry. Two types of ...

  11. Relation of arginine-lysine antagonism to herpes simplex growth in tissue culture.

    Science.gov (United States)

    Griffith, R S; DeLong, D C; Nelson, J D

    1981-01-01

    In the studies conducted, arginine deficiency suppressed herpes simplex virus replication in tissue culture. Lysine, an analog of arginine, as an antimetabolite, antagonized the viral growth-promoting action of arginine. The in vitro data may be the basis for the observation that patients prone to herpetic lesions and other related viral infections, particularly during periods of stress, should abstain from arginine excess and may also require supplemental lysine in their diet.

  12. Endothelial cells stimulate growth of normal and cancerous breast epithelial cells in 3D culture

    Directory of Open Access Journals (Sweden)

    Magnusson Magnus K

    2010-07-01

    Full Text Available Abstract Background Epithelial-stromal interaction provides regulatory signals that maintain correct histoarchitecture and homeostasis in the normal breast and facilitates tumor progression in breast cancer. However, research on the regulatory role of the endothelial component in the normal and malignant breast gland has largely been neglected. The aim of the study was to investigate the effects of endothelial cells on growth and differentiation of human breast epithelial cells in a three-dimensional (3D co-culture assay. Methods Breast luminal and myoepithelial cells and endothelial cells were isolated from reduction mammoplasties. Primary cells and established normal and malignant breast cell lines were embedded in reconstituted basement membrane in direct co-culture with endothelial cells and by separation of Transwell filters. Morphogenic and phenotypic profiles of co-cultures was evaluated by phase contrast microscopy, immunostaining and confocal microscopy. Results In co-culture, endothelial cells stimulate proliferation of both luminal- and myoepithelial cells. Furthermore, endothelial cells induce a subpopulation of luminal epithelial cells to form large acini/ducts with a large and clear lumen. Endothelial cells also stimulate growth and cloning efficiency of normal and malignant breast epithelial cell lines. Transwell and gradient co-culture studies show that endothelial derived effects are mediated - at least partially - by soluble factors. Conclusion Breast endothelial cells - beside their role in transporting nutrients and oxygen to tissues - are vital component of the epithelial microenvironment in the breast and provide proliferative signals to the normal and malignant breast epithelium. These growth promoting effects of endothelial cells should be taken into consideration in breast cancer biology.

  13. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    growth rate of the fungus were independent of pH when grown in batch cultivations. The specific glucoamylase productivity increased linearly with the specific growth rate in the range 0-0.1 h(-1) and was constant in the range 0.1-0.2 h(-1) Maltose and maltodextrin were non-inducing carbon sources...

  14. Control and Optimization of Batch Chemical Processes

    OpenAIRE

    Rohani, Sohrab; Chhabra, Raj; Bonvin, Dominique; François, Grégory

    2017-01-01

    A batch process is characterized by the repetition of time-varying operations of finite duration. Due to the repetition, there are two independent “time” variables, namely, the run time during a batch and the batch index. Accordingly, the control and optimization objectives can be defined for a given batch or over several batches. This chapter describes the various control and optimization strategies available for the operation of batch processes. These include online and run-to-run control o...

  15. Growth theory after Keynes, part II: 75 years of obstruction by the mainstream economics culture

    Directory of Open Access Journals (Sweden)

    Hendrik Van den Berg

    2014-05-01

    Full Text Available Part I of this essay explained the sequence of events that enabled the neoclassical paradigm to regain its dominant position in mainstream economics following serious challenges by ‘Keynesian’ economists. This second essay seeks to answer the question of why the economics profession was so willing to sustain the neoclassical paradigm in the face of the reality-based challenges by ‘Keynesian’ economists like Harrod and Domar. The answer is sought in the culture of economics, the history of science in general, and the study of power in the field of political economy. This article draws heavily on the work of the French sociologist Pierre Bourdieu, who divides culture into habitus (procedures and dispositions and doxa (more abstract beliefs and philosophies, in order to provide insight into how culture affects economic thinking. Bourdieu’s concept of symbolic violence helps to explain how a narrower neoclassical growth model was enthusiastically accepted as a replacement for the ‘Keynesian’ Harrod-Domar growth model. Financial and business interests clearly understood the power of culture and they used their accumulated wealth to support the neoliberal doxa and neoclassical habitus that would induce economists to willingly provide intellectual cover for policies that benefitted those financial and business interests. We conclude with a discussion on how the history of thought on economic development might have evolved if the Keynesian paradigm, and its dynamic Harrod-Domar model, had prevailed

  16. Limiting factors in Escherichia colifed-batch production of recombinant proteins

    DEFF Research Database (Denmark)

    Sanden, A.M.; Prytz, I.; Tubelekas, I.

    2003-01-01

    recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation......recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation...

  17. Data-driven batch schuduling

    Energy Technology Data Exchange (ETDEWEB)

    Bent, John [Los Alamos National Laboratory; Denehy, Tim [GOOGLE; Arpaci - Dusseau, Remzi [UNIV OF WISCONSIN; Livny, Miron [UNIV OF WISCONSIN; Arpaci - Dusseau, Andrea C [NON LANL

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  18. About the performance of Sphaerotilus natans to reduce hexavalent chromium in batch and continuous reactors

    International Nuclear Information System (INIS)

    Caravelli, Alejandro H.; Zaritzky, Noemi E.

    2009-01-01

    The hexavalent chromium biological reduction constitutes a safe and economical detoxification procedure of wastewaters containing Cr(VI). However, little research has been done to evaluate Cr(VI) tolerance and reduction capacity of microbial cultures under different growth conditions. The aims of this work were (a) to evaluate the capacity of Sphaerotilus natans to reduce Cr(VI) to Cr(III) in a continuous system limited in carbon and energy source or in nitrogen source, (b) to evaluate the toxic effect of Cr(VI) on this microorganism, (c) to carry out a complete analysis of Cr(VI) reduction by S. natans not only in continuous regime but also in batch system, and (d) to model the obtained results mathematically. S. natans exhibited great resistance to Cr(VI) (19-78 mg l -1 ) and optimal growth in continuous and batch systems using a mineral medium supplemented only with citric acid as organic substrate. In carbon- and energy-limited continuous systems, a maximum percentual decrease in Cr(VI) by 13% was reached for low influent Cr(VI) concentration (4.3-5.32 mgCr(VI) l -1 ); the efficiency of the process did not notoriously increase as the length of cellular residence time was increased from 4.16 to 50 h. A nitrogen-limited continuous operation with a cellular residence time of 28.5 h resulted in a Cr(VI) decrease of approximately 26-32%. In batch system, a mathematical model allowed to predict the Cr(VI) concentration as a function of time and the ratio between the initial Cr(VI) concentration and that of the biomass. High concentrations of initial Cr(VI) and biomass produced the highest performance of the process of Cr(VI) reduction reached in batch system, aspects which should be considered in detoxification strategies of wastewaters.

  19. Effect of radiation-degraded chitosan on growth promotion of flower plant in tissue culture

    Energy Technology Data Exchange (ETDEWEB)

    Luan, Le Quang; Ha, Vo Thi Thu; Hai, Le; Hien, Nguyen Quoc [Vietnam Atomic Energy Commission, Nuclear Research Institute, Dalat (Viet Nam); Nagasawa, Naotsugu; Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2002-03-01

    Radiation is a useful tool for degradation of polysaccharides, such as starch, carrageenan, alginate and chitin/chitosan. The viscosity molecular weight (Mw) of chitosan with 80% degree of deacetylation was reduced to 1.5 x 10{sup 5} by irradiation of 50kGy in solid phase. The solution of 10% of chitosan with Mw ca. 15 x 10{sup 5} was then irradiated at doses ranging 10-250kGy for further degradation and the products were supplemented into cultural media for testing of plant growth promotion effect. The results indicated that irradiated chitosan showed a strong growth-promotion effect on the increase of the length of shoot, the length of root and fresh biomass for flower plants namely Limonium latifolium, Eustoma grandiflorum and Chrysanthemum morifolium in tissue culture. The growth-promotion effect was obtained by the treatments with 50ppm of chitosan irradiated at the doses of 75-100kGy in 10% solution. The suitable concentrations of chitosan irradiated at 100kGy are ca. 100ppm for C. morifolium, 30ppm for E. grandiflorum and 40ppm for L. latifolium. In addition, our study also indicated that the survival ratio of transferred flower plantlets treated with irradiated chitosan was improved after acclimatizing for 30 days in the greenhouse. Accordingly, it is concluded that degraded chitosan obtained by radiation degradation technique is effective as a plant growth promoter as well as irradiated alginate. (author)

  20. A Study On Effect Of Added Neutralisers On Starter Culture Growth In Fermented Milks

    Directory of Open Access Journals (Sweden)

    Rajanna.M

    2017-06-01

    Full Text Available The Dairy starter culture is referred to carefully selection of desirable microorganisms. Those are intentionally added to milk during conversion into cheese dahi yoghurt and other fermented dairy products to bring about specific changes in the appearance body and texture flavor and desired organoleptic characteristics of the final product. The quality of milk itself has an important bearing on the growth of starter organisms. The mastitis milk has abnormal in composition and such milk with high salt concentration does not support the growth of starter culture that leads to production of poor quality of fermented dairy products with week body.. The presence of certain neutralizing substances performed in milk has found to interfere with growth of starters. There was a definite lag in the growth of the starter organisms as well as acid development when neutralizers were added to raw milk samples. This may be due to the bacteriostatic effect of added neutralizers. But discrepancy was seen to the greatest extent in the case of neutralized mastitis and highly advanced lactation milks and to a lesser degree on the early lactation milk obtained on the 4th and 5th days.

  1. Some further characteristics of the growth of Naegleria fowleri and N. gruberi in axenic culture.

    Science.gov (United States)

    Cerva, L

    1978-01-01

    The effects of pH, various viscosity of the medium, changed ratio between the concentrations of dissolved and corpuscular components in the medium, and dissolved inorganic salts on the growth of axenic cultures of Naegleria fowleri and N. gruberi have been studied. The cultures were grown in liquid CALYG and BCS media. The pH optimum was 6.5 for N. fowleri and 6.0--6.5 for N. gruberi. No negative influence on the growth of N. fowleri was observed even at 0.5% concentration of highly viscous methylcellulose, whereas the growth of N. gruberi was distinctly inhibited by more than 0.2% of methycellulose. N. fowleri preferred the osmotorphic and N. gruberi phagotrophic nutrition in the given system of cultivation. The growth of both Naegleria species was inhibited by 0.1 N concentration of sodium chloride and potassium chloride without any significant difference in the tolerance. The inhibitory effect of these salts correlated primarily with the concentration of chloride anion. The ability to grow in a medium with increased viscosity and the preference for osmotrophic nutrtion are, besides the higher temperature optimum determined earlier, further characteristics of the pathogenic species N. fowleri.

  2. Changes in pyridine metabolism profile during growth of trigonelline-forming Lotus japonicus cell cultures.

    Science.gov (United States)

    Yin, Yuling; Matsui, Ayu; Sakuta, Masaaki; Ashihara, Hiroshi

    2008-12-01

    Changes in the profile of pyridine metabolism during growth of cells were investigated using trigonelline-forming suspension-cultured cells of Lotus japonicus. Activity of the de novo and salvage pathways of NAD biosynthesis was estimated from the in situ metabolism of [(3)H] quinolinic acid and [(14)C] nicotinamide. Maximum activity of the de novo pathway for NAD synthesis was found in the exponential growth phase, whereas activity of the salvage pathway was increased in the lag phase of cell growth. Expression profiles of some genes related to pyridine metabolism were examined using the expression sequence tags obtained from the L. japonicus database. Transcript levels of NaPRT and NIC, encoding salvage enzymes, were enhanced in the lag phase of cell growth, whereas the maximum expression of NADS was found in the exponential growth phase. Correspondingly, the activities of the salvage enzymes, nicotinate phosphoribosyltransferase (EC 2.4.2.11) and nicotinamidase (EC 3.5.1.19), increased one day after transfer of the stationary phase cells to the fresh medium. The greatest in situ trigonelline synthesis, both from [(3)H] quinolinic acid and [(14)C] nicotinamide, was found in the stationary phase of cell growth. The role of trigonelline in leguminous plants is discussed.

  3. GROWTH CAPACITY OF BACILLUS POTENTIAL STARTER STRAINS ISOLATED FROM COCOA BEANS FERMENTATION UNDER CULTURE STRESS CONDITIONS

    Directory of Open Access Journals (Sweden)

    WILFRIED YAO

    2017-06-01

    Full Text Available The study investigates the growth capacity of Bacillus with pectinolytic activity, acidifying and citrate metabolism capacities under culture stress conditions. Spontaneous heaps fermentation was conducted from cocoa of six producing regions of Côte d’Ivoire. Bacillus isolated using plate agar on nutrient medium were analyzed for pectinolytic enzymes production, citric acid breakdown, acidification and growth capacity under different stress conditions. A total of 970 Bacillus strains were isolated and 44.53 % of them produced pectinolytic activity. Among pectinolytic strains, 163 (37.73 % exhibited acidifying and citrate metabolism capacity. Five (5 of these strains exhibited a strong thermotolerance at 50 ºC with the optimal growth at 35 ºC and a good capacity to grow at pH 4 to pH 8. Moreover, sugar concentrations ranged 5 to 25 % showed low effect on all tested strains growth with a maximum growth at 5 % fructose and sucrose concentration and at 15% glucose concentration. However, ethanol stress conditions (up to 8 % repress strongly growth capacity of the strains analyzed. This study indicates that Bacillus strains involved in Ivorian cocoa fermentation possess some properties essential for a well-fermented cocoa. Therefore, these results show that Bacillus studied should be potential candidate as starter for cocoa beans fermentation control.

  4. Growth and Development of Colletotrichum gloeosporioides f. alatae During Culture in Liquid Medium

    Directory of Open Access Journals (Sweden)

    Laura E. Cerón Rincón

    2006-01-01

    Full Text Available Some characteristics known as virulence factors for Colletotrichum sp. genus, like: weight of the produced mycelium, sporulation, poligalacturonase activity and pH medium were evaluated during the growth of C. gloeosporioides f. alatae in three liquid medium commonly used for fungi culture (Czapeck, Martin broth and potato broth and additionally (Czapeck with yam extract as the only source of carbon. After of 17 days of growth, maximum values were obtained for the above parameters in the last medium, compared with others growth media evaluated. The implemented medium with yam extract, supply nutritional requirements of the pathogen for the development of characteristic factors related with mechanism of infections that may play a role in the pathogenesis.

  5. Using a medium of free amino acids to produce penicillin g acylase in fed-batch cultivations of Bacillus megaterium ATCC 14945

    Directory of Open Access Journals (Sweden)

    R. G. Silva

    2006-03-01

    Full Text Available The production of penicillin G acylase (PGA, an important industrial enzyme from a wild strain of Bacillus megaterium using a pool of free amino acids as substrate was studied in a bench-scale bioreactor. Experiments carried out in shakers showed that the substitution of casein for free amino acids in the presence of cheese whey was the culture medium that provided the highest productivity. Several cultivations were carried out in a bioreactor operated in either batch or fed-batch mode. Batch runs showed that enzyme production is associated with microorganism growth. The following set of amino acids was preferentially consumed: Ala, Arg, Asp, Gly, Lys, Ser, Thr and Trp. On the other hand, the rates of consumption of His, Ile, Leu, Met, Phe, Pro, Tyr and Val were lower.

  6. Adaptive Batch Mode Active Learning.

    Science.gov (United States)

    Chakraborty, Shayok; Balasubramanian, Vineeth; Panchanathan, Sethuraman

    2015-08-01

    Active learning techniques have gained popularity to reduce human effort in labeling data instances for inducing a classifier. When faced with large amounts of unlabeled data, such algorithms automatically identify the exemplar and representative instances to be selected for manual annotation. More recently, there have been attempts toward a batch mode form of active learning, where a batch of data points is simultaneously selected from an unlabeled set. Real-world applications require adaptive approaches for batch selection in active learning, depending on the complexity of the data stream in question. However, the existing work in this field has primarily focused on static or heuristic batch size selection. In this paper, we propose two novel optimization-based frameworks for adaptive batch mode active learning (BMAL), where the batch size as well as the selection criteria are combined in a single formulation. We exploit gradient-descent-based optimization strategies as well as properties of submodular functions to derive the adaptive BMAL algorithms. The solution procedures have the same computational complexity as existing state-of-the-art static BMAL techniques. Our empirical results on the widely used VidTIMIT and the mobile biometric (MOBIO) data sets portray the efficacy of the proposed frameworks and also certify the potential of these approaches in being used for real-world biometric recognition applications.

  7. Growth of gametophytes and sporophytes of Grateloupia subpectinata (Rhodophyta) in culture

    Science.gov (United States)

    Adharini, Ratih Ida; Kim, Hyung Geun

    2016-09-01

    Comparison of growing thalli in alternating haploid and diploid phases of Grateloupia subpectinata (Rhodophyta) was studied. Fertile thalli from gametophyte and tetrasporophyte of G. subpectinata were collected from Yangyang, on the eastern coast of Korea. The size of the released tetraspores and carpospores was measured; the spores were then incubated at the temperature of 20°C, irradiance of 40 μmol photon m-2s-1 and photoperiod of 12L and 12D. Carpospores were also cultivated in the same conditions as the tetraspores culture. The crusts were subsequently transferred to a tank culture after six months. The specific growth rate (SGR) was measured by observing 50 crusts and 30 thalli. The released carpospores had a larger diameter (9.98 μm) than the tetraspores (9.38 μm). The crusts from the carpospores also show a higher specific growth rate (14.04% d-1) than tetraspores (13.39% d-1). After being transferred and cultured in a tank, the upright thalli grew slowly in May-June (13-15°C) and rapidly in July-September (17-22°C). The length of growing thalli of sporophyte from carpospores also revealed a higher specific growth rate (2.83% d-1) than gametophytic thalli (2.38% d-1). The specific growth rate of crusts and thalli developed from carpospores was higher than that of the crusts developed from tetraspores. This result suggests that the cultivation of sporophytes may be more profitable than gametophytes because harvesting can be done more efficiently.

  8. Valproic acid promotes human hair growth in in vitro culture model.

    Science.gov (United States)

    Jo, Seong Jin; Choi, Soon-Jin; Yoon, Sun-Young; Lee, Ji Yeon; Park, Won-Seok; Park, Phil-June; Kim, Kyu Han; Eun, Hee Chul; Kwon, Ohsang

    2013-10-01

    β-Catenin, the transducer of Wnt signaling, is critical for the development and growth of hair follicles. In the absence of Wnt signals, cytoplasmic β-catenin is phosphorylated by glycogen synthase kinase (GSK)-3 and then degraded. Therefore, inhibition of GSK-3 may enhance hair growth via β-catenin stabilization. Valproic acid is an anticonvulsant and a mood-stabilizing drug that has been used for decades. Recently, valproic acid was reported to inhibit GSK-3β in neuronal cells, but its effect on human hair follicles remains unknown. To determine the effect of VPA on human hair growth. We investigated the effect of VPA on cultured human dermal papilla cells and outer root sheath cells and on an in vitro culture of human hair follicles, which were obtained from scalp skin samples of healthy volunteers. Anagen induction by valproic acid was evaluated using C57BL/6 mice model. Valproic acid not only enhanced the viability of human dermal papilla cells and outer root sheath cells but also promoted elongation of the hair shaft and reduced catagen transition of human hair follicles in organ culture model. Valproic acid treatment of human dermal papilla cells led to increased β-catenin levels and nuclear accumulation and inhibition of GSK-3β by phosphorylation. In addition, valproic acid treatment accelerated the induction of anagen hair in 7-week-old female C57BL/6 mice. Valproic acid enhanced human hair growth by increasing β-catenin and therefore may serve as an alternative therapeutic option for alopecia. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Inhibition of cell growth by EGR-1 in human primary cultures from malignant glioma

    Directory of Open Access Journals (Sweden)

    Gagliardi Franco

    2004-01-01

    Full Text Available Abstract Background The aim of this work was to investigate in vitro the putative role of EGR-1 in the growth of glioma cells. EGR-1 expression was examined during the early passages in vitro of 17 primary cell lines grown from 3 grade III and from 14 grade IV malignant astrocytoma explants. The explanted tumors were genetically characterized at the p53, MDM2 and INK4a/ARF loci, and fibronectin expression and growth characteristics were examined. A recombinant adenovirus overexpressing EGR-1 was tested in the primary cell lines. Results Low levels of EGR-1 protein were found in all primary cultures examined, with lower values present in grade IV tumors and in cultures carrying wild-type copies of p53 gene. The levels of EGR-1 protein were significantly correlated to the amount of intracellular fibronectin, but only in tumors carrying wild-type copies of the p53 gene (R = 0,78, p = 0.0082. Duplication time, plating efficiency, colony formation in agarose, and contact inhibition were also altered in the p53 mutated tumor cultures compared to those carrying wild-type p53. Growth arrest was achieved in both types of tumor within 1–2 weeks following infection with a recombinant adenovirus overexpressing EGR-1 but not with the control adenovirus. Conclusions Suppression of EGR-1 is a common event in gliomas and in most cases this is achieved through down-regulation of gene expression. Expression of EGR-1 by recombinant adenovirus infection almost completely abolishes the growth of tumor cells in vitro, regardless of the mutational status of the p53 gene.

  10. A defined growth medium with very low background carbon for culturing Clostridium thermocellum.

    Science.gov (United States)

    Holwerda, Evert K; Hirst, Kyle D; Lynd, Lee R

    2012-06-01

    A growth medium was developed for cultivation of Clostridium thermocellum ATCC 27405 in which "background" carbon present in buffers, reducing agents, chelating agents, and growth factors was a small fraction of the carbon present in the primary growth substrate. Background carbon was 1.6% of primary substrate carbon in the low-carbon (LC) medium, whereas it accounts for at least 40% in previously reported media. Fermentation of cellulose in LC medium was quite similar to Medium for Thermophilic Clostridia (MTC), a commonly used growth medium that contains background carbon at 88% of primary substrate carbon. Of particular note, we found that the organism can readily be cultivated by eliminating some components, lowering the concentrations of others, and employing a tenfold lower concentration of reducing agent. As such, we were able to reduce the amount of background carbon 55-fold compared to MTC medium while reaching the same cell biomass concentration. The final mass ratios of the products acetate:ethanol:formate were 5:3.9:1 for MTC and 4.1:1.5:1 for LC medium. LC medium is expected to facilitate metabolic studies involving identification and quantification of extracellular metabolites. In addition, this medium is expected to be useful in studies of cellulose utilization by anaerobic enrichment cultures obtained from environmental inocula, and in particular to diminish complications arising from metabolism of carbon-containing compounds other than cellulose. Finally, LC medium provides a starting point for industrial growth media development.

  11. Effects of nitrendipine on growth activity in cultured vascular smooth muscle cells.

    Science.gov (United States)

    Absher, M P; Baldor, L; Warshaw, D M

    1988-01-01

    Proliferation and migration of smooth muscle cells (SMCs) in the arterial wall may play a role in the development of atherosclerosis and hypertension. If cell migration and proliferation are dependent on extracellular calcium, then treatment with calcium channel blockers such as nitrendipine may alter these cellular responses. In the studies reported here, proliferation and migration activities were assessed in cultured bovine carotid artery smooth muscle cells exposed to nitrendipine. SMCs in long-term culture are characterized by periods of either stable or enhanced proliferative activity. During the stable periods, 1 microM nitrendipine has no effect on proliferation, but during periods of enhanced proliferation, 1 microM nitrendipine augments growth by approximately 20%. SMC migration rates and interdivision times were determined from analysis of time-lapse cinematography films. During stable periods of growth, cell migration rate was inversely related to interdivision time (i.e., fast migrating cells had the shortest interdivision times). Treatment with 1 microM nitrendipine abolished the relationship between migration rate and interdivision time and prolonged interdivision times. These data suggest that the ability of nitrendipine to alter SMC proliferation, interdivision time, and migration is dependent upon the overall proliferative state of the culture.

  12. Growth of ABT-5 bacteria culture in whey supplemented with whey protein concentrate

    Directory of Open Access Journals (Sweden)

    Bojan Matijević

    2010-09-01

    Full Text Available The objective of this research was to decrease the duration of whey fermentation and to analyze the impact of whey protein concentrates (WPC addition on growth and activity as well as on survival of mixed ABT-5 culture bacteria (Lactobacillus acidophilus, Bifidobacterium spp. and Streptococcus thermophilus during 28 days of fermented whey cold storage (5 °C. Whey fermentation was observed at 37 °C with and without 1.5 and 3 % WPC addition. Whey fermentation with mixed ABT-5 bacterial culture took about 6.5 hours, and WPC did not affect the fermentation dynamics, regardless of the added amount. The viable cell count of Lactobacillus acidophilus was higher in fermented whey with WPC (about 7.13 log CFU/mL compared to whey without WPC (about 6.63 log CFU/mL. WPC addition did not affect the growth of bacteria Bifidobacterium spp. and Streptococcus thermophilus nor the survival of ABT-5 culture bacteria in fermented whey during 28 days of cold storage (5 °C.

  13. Growth and enzymatic responses of phytopathogenic fungi to glucose in culture media and soil

    Directory of Open Access Journals (Sweden)

    Beatriz de Oliveira Costa

    2012-03-01

    Full Text Available The effect of inoculation of Aspergillus flavus, Fusarium verticillioides, and Penicillium sp. in Dystrophic Red Latosol (DRL and Eutroferric Red Latosol (ERL soils with or without glucose on the total carbohydrate content and the dehydrogenase and amylase activities was studied. The fungal growth and spore production in culture medium with and without glucose were also evaluated. A completely randomized design with factorial arrangement was used. The addition of glucose in the culture medium increased the growth rate of A. flavus and Penicillium sp. but not of F. verticillioides. The number of spores increased 1.2 for F. verticillioides and 8.2 times for A. flavus in the medium with glucose, but was reduced 3.5 times for Penicillium sp. The total carbohydrates contents reduced significantly according to first and second degree equations. The consumption of total carbohydrates by A. flavus and Penicillium sp. was higher than the control or soil inoculated with F. verticillioides. The addition of glucose to soils benefited the use of carbohydrates, probably due to the stimulation of fungal growth. Dehydrogenase activity increased between 1.5 to 1.8 times (p <0.05 in soils with glucose and inoculated with the fungi (except F. verticillioides, in relation to soil without glucose. Amylase activity increased 1.3 to 1.5 times due to the addition of glucose in the soil. Increased amylase activity was observed in the DRL soil with glucose and inoculated with A. flavus and Penicillium sp. when compared to control.

  14. Growth inhibition of selected microorganisms by an association of dairy starter cultures and probiotics

    Directory of Open Access Journals (Sweden)

    Beniamino T. Cenci-Goga

    2015-05-01

    Full Text Available Several growth curves for selected pathogens and hygiene indicators alone and vs selected dairy starter cultures (LAB and commercial probiotics have been performed. All strains for LAB and commercial probiotics were inoculated as pure cultures into skim milk to get an initial cocci:bacilli:enterocci ratio of 2:1:1 and a concentration of approximately 107 cfu mL–1 until challenge vs selected pathogens and hygiene indicators. Selected pathogens came from the collection of the Laboratorio di Ispezione degli Alimenti di O.A. or were reference strains (Escherichia coli, CSH26 K12, Staphylococcus aureus 27R, Salmonella Derby 27, Pseudomonas fluorescens ATCC 13525, Listeria innocua ATCC 33090. Each strain was inoculated into skim milk to get an initial concentration of approximately 106 cfu mL–1. Growth curves in skim milk for the following challenges were studied: i sterility control; ii association LAB; iii association of LAB vs each selected pathogen or hygiene indicator; iv selected pathogen or hygiene indicator alone. The challenges were carried out in BHI broth and in skim milk at 37°C. The highest reduction was observed in milk but in general the association of LAB and the probiotic was able to limit the growth of pathogens and hygiene indicators.

  15. Simultaneous environmental manipulations in semi-perfusion cultures of CHO cells producing rh-tPA

    OpenAIRE

    Vergara,Mauricio; Becerra,Silvana; Díaz-Barrera,Alvaro; Berrios,Julio; Altamirano,Claudia

    2012-01-01

    We evaluated the combined effect of decreasing the temperature to a mild hypothermia range (34 and 31ºC) and switching to a slowly metabolizable carbon source (glucose substituted by galactose) on the growth and production of a recombinant human tissue plasminogen activator (rh-tPA) by Chinese hamster ovary cells in batch and semi-perfusion cultures. In batch cultures using glucose as a carbon source, decreasing the temperature caused a reduction in cell growth and an increase in specific pro...

  16. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    OpenAIRE

    He, Guo-qing; Kong, Qing; Chen, Qi-he; Ruan, Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, th...

  17. Influence of feeding conditions on clavulanic acid production in fed-batch cultivation with medium containing glycerol.

    Science.gov (United States)

    Teodoro, Juliana C; Baptista-Neto, Alvaro; Cruz-Hernández, Isara L; Hokka, Carlos O; Badino, Alberto C

    2006-09-01

    First, the effect of different levels of nitrogen source on clavulanic acid (CA) production was evaluated in batch cultivations utilizing complex culture medium containing glycerol and three different levels of soy protein isolate (SPI). Cellular growth, evaluated in terms of the rheological parameter K, was highest with a SPI concentration of 30 g.L(-1) (4.42 g.L(-1) N total). However, the highest production of CA (380 mg.L(-1)) was obtained when an intermediate concentration of 20 g.L(-1) of SPI (2.95 g.L(-1) total N) was used. To address this, the influences of volumetric flow rate (F) and glycerol concentration in the complex feed medium (Cs(F)) in fed-batch cultivations were investigated. The best experimental condition for CA production was F=0.01 L.h(-1) and Cs(F)=120 g.L(-1), and under these conditions maximum CA production was practically twice that obtained in the batch cultivation. A single empirical equation was proposed to relate maximum CA production with F and Cs(F) in fed-batch experiments.

  18. Primary culture and growth characteristics of four different species of lens epithelial cells

    Directory of Open Access Journals (Sweden)

    Li-Xia Ji

    2015-07-01

    Full Text Available AIM: To explore the primary culture conditions for four kinds of lens epithelial cells(LECsof rat, rabbit, dog, and human, and measure their growth characteristics. METHODS: The lens capsule or anterior capsular tissue of rat, rabbit, dog and patient were removed by different methods, and they were cut into tiny pieces for primary culture by modified tissue adherent method. The morphological features of four kinds of LECs were observed under an inverted microscope.RESULTS: Four kinds of LECs of rat, rabbit, dog and human could be cultured primarily by tissue adherent method. With the evolution of tissue source, the adherent capacity of LECs gradually strengthened, cells form were changed from irregular polygon to oval, nucleus rounded and cytoplasm enriched gradually. Four kinds of LECs had fibrotic changes after several passages.CONCLUSION: LECs of rat, rabbit, dog and human can be primarily cultured. This method lays the foundation for the mechanism research of caratact and related fields on the cellular and molecular levels.

  19. Lactic acid bacteria as protective cultures in fermented pork meat to prevent Clostridium spp. growth.

    Science.gov (United States)

    Di Gioia, Diana; Mazzola, Giuseppe; Nikodinoska, Ivana; Aloisio, Irene; Langerholc, Tomaz; Rossi, Maddalena; Raimondi, Stefano; Melero, Beatriz; Rovira, Jordi

    2016-10-17

    In meat fermented foods, Clostridium spp. growth is kept under control by the addition of nitrite. The growing request of consumers for safer products has led to consider alternative bio-based approaches, the use of protective cultures being one of them. This work is aimed at checking the possibility of using two Lactobacillus spp. strains as protective cultures against Clostridium spp. in pork ground meat for fermented salami preparation. Both Lactobacillus strains displayed anti-clostridia activity in vitro using the spot agar test and after co-culturing them in liquid medium with each Clostridium strain. Only one of them, however, namely L. plantarum PCS20, was capable of effectively surviving in ground meat and of performing anti-microbial activity in carnis in a challenge test where meat was inoculated with the Clostridium strain. Therefore, this work pointed out that protective cultures can be a feasible approach for nitrite reduction in fermented meat products. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Regeneration efficiency based on genotype, culture condition and growth regulators of eggplant (Solanum melongena L.

    Directory of Open Access Journals (Sweden)

    Md Abdul Muktadir

    2016-01-01

    Full Text Available Several experiments were carried out to establish an efficient regenerating protocol for cultivated eggplant varieties. Among the five varieties cultured on Murashige and Skoog (MS medium with free plant growth regulator (PGR, Nayantara performed better considering the number of shoots/explant (2.48. Considering explant types and culture conditions, better performance was observed (3.68 shoots/explant when seed germination in the dark was proceeded by bottom hypocotyl segments cultured under dark conditions. A higher rate of shoot regeneration was observed in Nayantara when cultured in Zeatin Riboside (ZR and Thidizuron (TDZ supplemented MS medium. The highest number of shoots per explant was produced on MS medium supplemented with 2.0 mg/L ZR and 0.1 mg/L indole acetic acid (6.65 shoots/explant. Proliferation and elongation of the regenerated shoots were obtained in the MS medium with free PGR. The best rooting performance was observed in MS medium supplemented with 2.0 mg/L indole butyric acid. Plantlets with well developed roots and shoots were successfully transferred to soil.

  1. Modulation of cultured porcine granulosa cell responsiveness to follicle stimulating hormone and epidermal growth factor

    International Nuclear Information System (INIS)

    Buck, P.A.

    1986-01-01

    Ovarian follicular development is dependent upon the coordinated growth and differentiation of the granulosa cells which line the follicle. Follicle stimulating hormone (FSH) induces granulosa cell differentiation both in vivo and in vitro. Epidermal growth factor (EGF) stimulates granulosa cell proliferation in vitro. The interaction of these two effectors upon selected parameters of growth and differentiation was examined in monolayer cultures of porcine granulose cells. Analysis of the EGF receptor by 125 I-EGF binding revealed that the receptor was of high affinity with an apparent dissociation constant of 4-6 x 10 -10 M. The average number of receptors per cell varied with the state of differentiation both in vivo and in vitro; highly differentiated cells bound two-fold less 125 I-EGF and this effect was at least partially induced by FSH in vitro. EGF receptor function was examined by assessing EGF effects on cell number and 3 H-thymidine incorporation. EGF stimulated thymidine incorporation in both serum-free and serum-supplemented culture, but only in serum-supplemented conditions was cell number increased. EGF receptor function was inversely related to the state of differentiation and was attenuated by FSH. The FSH receptor was examined by 125 I-FSH binding. EGF increased FSH receptor number, and lowered the affinity of the receptor. The function of these receptors was assessed by 125 I-hCG binding and progesterone radioimmunoassay. If EGF was present continuously in the cultures. FSH receptor function was attenuated regardless of FSH receptor number. A preliminary effort to examine the mechanism of this interaction was performed by analyzing hormonally controlled protein synthesis with 35 S-methionine labeling, SDS polyacrylamide gel electrophoresis and fluorography. FSH promoted the expression of a 27,000 dalton protein. This effect was attenuated by EGF

  2. Inhibition of Fusarium graminearum growth in flour gel cultures by hexane-soluble compounds from oat (Avena sativa L.) flour.

    Science.gov (United States)

    Doehlert, Douglas C; Rayas-Duarte, Patricia; McMullen, Michael S

    2011-12-01

    Fusarium head blight, incited by the fungus Fusarium graminearum, primarily affects wheat (Triticum aestivum) and barley (Hordeum vulgarum), while oat (Avena sativa) appears to be more resistant. Although this has generally been attributed to the open panicle of oats, we hypothesized that a chemical component of oats might contribute to this resistance. To test this hypothesis, we created culture media made of wheat, barley, and oat flour gels (6 g of flour in 20 ml of water, gelled by autoclaving) and inoculated these with plugs of F. graminearum from actively growing cultures. Fusarium growth was measured from the diameter of the fungal plaque. Plaque diameter was significantly smaller on oat flour cultures than on wheat or barley cultures after 40 to 80 h of growth. Ergosterol concentration was also significantly lower in oat cultures than in wheat cultures after growth. A hexane extract from oats added to wheat flour also inhibited Fusarium growth, and Fusarium grew better on hexane-defatted oat flour. The growth of Fusarium on oat flour was significantly and negatively affected by the oil concentration in the oat, in a linear relationship. A hexane-soluble chemical in oat flour appears to inhibit Fusarium growth and might contribute to oat's resistance to Fusarium head blight. Oxygenated fatty acids, including hydroxy, dihydroxy, and epoxy fatty acids, were identified in the hexane extracts and are likely candidates for causing the inhibition.

  3. Growth and development of cultured carrot cells and embryos under spaceflight conditions

    Science.gov (United States)

    Krikorian, A. D.; Dutcher, F. R.; Quinn, C. E.; Steward, F. C.

    1981-01-01

    Morphogenetically competent proembryonic cells and well-developed somatic embryos of carrot at two levels of organization were exposed for 18.5 days to a hypogravity environment aboard the Soviet Biosatellite Cosmos 1129. It was confirmed that cultured totipotent cells of carrot can give rise to embryos with well-developed roots and minimally developed shoots. It was also shown that the space hypogravity environment could support the further growth of already-organized, later somatic embryonic stages and give rise to fully developed embryo-plantlets with roots and shoots.

  4. Effects of Growth Media on the Diversity of Culturable Fungi from Lichens.

    Science.gov (United States)

    Muggia, Lucia; Kopun, Theodora; Grube, Martin

    2017-05-17

    Microscopic and molecular studies suggest that lichen symbioses contain a plethora of associated fungi. These are potential producers of novel bioactive compounds, but strains isolated on standard media usually represent only a minor subset of these fungi. By using various in vitro growth conditions we are able to modulate and extend the fraction of culturable lichen-associated fungi. We observed that the presence of iron, glucose, magnesium and potassium in growth media is essential for the successful isolation of members from different taxonomic groups. According to sequence data, most isolates besides the lichen mycobionts belong to the classes Dothideomycetes and Eurotiomycetes. With our approach we can further explore the hidden fungal diversity in lichens to assist in the search of novel compounds.

  5. Growth and sporulation of Metarhizium flavoviride var. Flavoviride on culture media and lighting regimes

    Directory of Open Access Journals (Sweden)

    Onofre Sideney Becker

    2001-01-01

    Full Text Available Entomopathogenic fungi from the genus Metarhizium are largely used for the biological control of agricultural pests by conidia spreading on the field. Although conidia production is well studied in M. anisopliae, only few research studies were done in M. flavoviride. The present work was carried out alming to evaluate the Mycelial growth and sporulation of the entomopathogenic fungus Metarhizium flavoviride var. flavoviride growing at 27 ± 2°C on Potato-dextrose-agar (PDA, Czapek-agar (CZP and a complete agar medium (CM under three lighting regimes, (continuous illumination, light/dark cycle and an black light/dark cycle were investigated. A completely randomized 3 × 3 (culture media × lighting regime factorial design with four replicates was used. The best mycelial growth and sporulation occurred on the PDA and CM media under continuous illumination (P <= 0,05.

  6. Kinetic models of cell growth, substrate utilization and bio ...

    African Journals Online (AJOL)

    Bio-decolorization kinetic studies of distillery effluent in a batch culture were conducted using Aspergillus fumigatus. A simple model was proposed using the Logistic Equation for the growth, Leudeking-Piret kinetics for bio-decolorization, and also for substrate utilization. The proposed models appeared to provide a suitable ...

  7. The growth of bacteria on organic compounds in drinking water

    NARCIS (Netherlands)

    Kooij, van der D.

    1984-01-01

    Growth ("regrowth") of bacteria In drinking water distribution systems results in a deterioration of the water quality. Regrowth of chemoheterotrophic bacteria depends on the presence of organic. compounds that serve as a nutrient source for these bacteria. A batch-culture technique was

  8. Biodegradation and growth characteristics of a toluene-degrading ...

    African Journals Online (AJOL)

    A toluene-degrading strain was isolated from active sludge in this study. Both growth characteristic and the performance to degrade toluene by the strain in batch culture mode were evaluated. Results showed that the isolated strain presented a good ability to remove toluene with the maximum removal efficiency of 93.8%.

  9. Red Ginseng Extract Promotes the Hair Growth in Cultured Human Hair Follicles

    Science.gov (United States)

    Park, Gyeong-Hun; Park, Ki-young; Cho, Hong-il; Lee, Sang-Min; Han, Ji Su; Chang, Sung Eun; Lee, Mi Woo; Choi, Jee Ho; Moon, Kee Chan; Shin, Hyoseung; Kang, Yong Jung; Lee, Dong Hun

    2015-01-01

    Abstract Ginseng has been shown to promote hair growth in several recent studies. However, its effects on human hair follicles and its mechanisms of action have not been sufficiently elucidated. This study aimed to investigate the hair growth-promoting effects of red ginseng extract (RGE) and its ginsenosides. The proliferative activities of cultured human hair follicles treated with RGE and ginsenoside-Rb1 were assessed using Ki-67 immunostaining. Their effects on isolated human dermal papilla cells (hDPCs) were evaluated using cytotoxicity assays, immunoblot analysis of signaling proteins, and the determination of associated growth factors. We examined the ability of RGE and ginsenosides to protect hair matrix keratinocyte proliferation against dihydrotestosterone (DHT)-induced suppression and their effects on the expression of androgen receptor. The in vivo hair growth-promoting effect of RGE was also investigated in C57BL/6 mice. Both RGE and ginsenoside-Rb1 enhanced the proliferation of hair matrix keratinocytes. hDPCs treated with RGE or ginsenoside-Rb1 exhibited substantial cell proliferation and the associated phosphorylation of ERK and AKT. Moreover, RGE, ginsenoside-Rb1, and ginsenoside-Rg3 abrogated the DHT-induced suppression of hair matrix keratinocyte proliferation and the DHT-induced upregulation of the mRNA expression of androgen receptor in hDPCs. Murine experiments revealed that the subcutaneous injection of 3% RGE resulted in more rapid hair growth than the negative control. In conclusion, RGE and its ginsenosides may enhance hDPC proliferation, activate ERK and AKT signaling pathways in hDPCs, upregulate hair matrix keratinocyte proliferation, and inhibit the DHT-induced androgen receptor transcription. These results suggest that red ginseng may promote hair growth in humans. PMID:25396716

  10. Red ginseng extract promotes the hair growth in cultured human hair follicles.

    Science.gov (United States)

    Park, Gyeong-Hun; Park, Ki-young; Cho, Hong-il; Lee, Sang-Min; Han, Ji Su; Won, Chong Hyun; Chang, Sung Eun; Lee, Mi Woo; Choi, Jee Ho; Moon, Kee Chan; Shin, Hyoseung; Kang, Yong Jung; Lee, Dong Hun

    2015-03-01

    Ginseng has been shown to promote hair growth in several recent studies. However, its effects on human hair follicles and its mechanisms of action have not been sufficiently elucidated. This study aimed to investigate the hair growth-promoting effects of red ginseng extract (RGE) and its ginsenosides. The proliferative activities of cultured human hair follicles treated with RGE and ginsenoside-Rb1 were assessed using Ki-67 immunostaining. Their effects on isolated human dermal papilla cells (hDPCs) were evaluated using cytotoxicity assays, immunoblot analysis of signaling proteins, and the determination of associated growth factors. We examined the ability of RGE and ginsenosides to protect hair matrix keratinocyte proliferation against dihydrotestosterone (DHT)-induced suppression and their effects on the expression of androgen receptor. The in vivo hair growth-promoting effect of RGE was also investigated in C57BL/6 mice. Both RGE and ginsenoside-Rb1 enhanced the proliferation of hair matrix keratinocytes. hDPCs treated with RGE or ginsenoside-Rb1 exhibited substantial cell proliferation and the associated phosphorylation of ERK and AKT. Moreover, RGE, ginsenoside-Rb1, and ginsenoside-Rg3 abrogated the DHT-induced suppression of hair matrix keratinocyte proliferation and the DHT-induced upregulation of the mRNA expression of androgen receptor in hDPCs. Murine experiments revealed that the subcutaneous injection of 3% RGE resulted in more rapid hair growth than the negative control. In conclusion, RGE and its ginsenosides may enhance hDPC proliferation, activate ERK and AKT signaling pathways in hDPCs, upregulate hair matrix keratinocyte proliferation, and inhibit the DHT-induced androgen receptor transcription. These results suggest that red ginseng may promote hair growth in humans.

  11. A CMI (cell metabolic indicator)-based controller for achieving high growth rate Escherichia coli cultures.

    Science.gov (United States)

    Pepper, Matthew E; Wang, Li; Padmakumar, Ajay; Burg, Timothy C; Harcum, Sarah W; Groff, Richard E

    2014-01-01

    A large fraction of biopharmaceuticals are produced in Escherichia coli, where each new product and strain currently requires a high degree of growth characterization in benchtop and industrial bioreactors to achieve economical production protocols. The capability to use a standard set of sensors to characterize a system quickly without the need to conduct numerous experiments to determine stable growth rate for the strain would significantly decrease development time. This paper presents a cell metabolic indicator (CMI) which provides better insight into the E. coli metabolism than a growth rate value. The CMI is the ratio of the oxygen uptake rate (OUR) of the culture and the base addition rate (BAR) required to keep pH at a desired setpoint. The OUR and BAR are measured using a off-gas sensor and pH probe, respectively, and thus the CMI can be computed online. Experimental results demonstrate the relationship between CMI and the different cell metabolic states. A previously published model is augmented with acid production dynamics, allowing for comparison of the CMI-based controller with an open-loop controller in simulation. The CMI-based controller required little a priori knowledge about the E. coli strain in order to achieve a high growth rate. Since many different types of cells exhibit similar behaviors, the CMI concept can be extended to mammalian and stem cells.

  12. Growth performance of three pejerrey genetic groups in intensive culture system

    Directory of Open Access Journals (Sweden)

    Rafael Aldrighi Tavares

    2014-10-01

    Full Text Available This study examined the growth performance of Odontesthes bonariensis, O. humensis and hybrid (O. bonariensis X O. humensis in intensive culture system for a period of 180 days, using the body weight (W, total length (Lt, condition factor (CF, allometric coefficient (b, specific growth rate (SGR and estimates of body weight and maximum total length (Wmax, Ltmax as indicators. Fish were randomly selected from three genetic groups (Bonariensis, Humensis and Hybrid, divided into water recirculation system consisting of 12 tanks (50 L. 12 measurements of body weight and total length (0, 2, 7, 14, 21, 30, 45, 60, 75, 90, 120, 180 days were taken by means of a random sample of 10 subjects per replicate. All genetic groups grew in weight and length over the period analyzed, being influenced by the genetics of each species. O. bonariensis showed the best performance in growth and hybrid fish showed intermediate growth and estimated maximum body weight exceeding the pure species. Based on these results, it would be helpful the selective breeding and formation of domesticated strains.

  13. BatchJS: Implementing Batches in JavaScript

    NARCIS (Netherlands)

    D. Kasemier

    2014-01-01

    htmlabstractNone of our popular programming languages know how to handle distribution well. Yet our programs interact more and more with each other and our data resorts in databases and web services. Batches are a new addition to languages that can finally bring native support for distribution to

  14. Analysis of Adiabatic Batch Reactor

    Directory of Open Access Journals (Sweden)

    Erald Gjonaj

    2016-05-01

    Full Text Available A mixture of acetic anhydride is reacted with excess water in an adiabatic batch reactor to form an exothermic reaction. The concentration of acetic anhydride and the temperature inside the adiabatic batch reactor are calculated with an initial temperature of 20°C, an initial temperature of 30°C, and with a cooling jacket maintaining the temperature at a constant of 20°C. The graphs of the three different scenarios show that the highest temperatures will cause the reaction to occur faster.

  15. Effect of culture methods on individual variation in the growth of sea cucumber Apostichopus japonicus within a cohort and family

    Science.gov (United States)

    Qiu, Tianlong; Zhang, Libin; Zhang, Tao; Bai, Yucen; Yang, Hongsheng

    2014-07-01

    There is substantial individual variation in the growth rates of sea cucumber Apostichopus japonicus individuals. This necessitates additional work to grade the seed stock and lengthens the production period. We evaluated the influence of three culture methods (free-mixed, isolated-mixed, isolated-alone) on individual variation in growth and assessed the relationship between feeding, energy conversion efficiency, and individual growth variation in individually cultured sea cucumbers. Of the different culture methods, animals grew best when reared in the isolated-mixed treatment (i.e., size classes were held separately), though there was no difference in individual variation in growth between rearing treatment groups. The individual variation in growth was primarily attributed to genetic factors. The difference in food conversion efficiency caused by genetic differences among individuals was thought to be the origin of the variance. The level of individual growth variation may be altered by interactions among individuals and environmental heterogeneity. Our results suggest that, in addition to traditional seed grading, design of a new kind of substrate that changes the spatial distribution of sea cucumbers would effectively enhance growth and reduce individual variation in growth of sea cucumbers in culture.

  16. Insulin-like growth factor-II receptors in cultured rat hepatocytes: regulation by cell density

    International Nuclear Information System (INIS)

    Scott, C.D.; Baxter, R.C.

    1987-01-01

    Insulin-like growth factor-II (IGF-II) receptors in primary cultures of adult rat hepatocytes were characterized and their regulation by cell density examined. In hepatocytes cultured at 5 X 10(5) cells per 3.8 cm2 plate [ 125 I]IGF-II bound to specific, high affinity receptors (Ka = 4.4 +/- 0.5 X 10(9) l/mol). Less than 1% cross-reactivity by IGF-I and no cross-reactivity by insulin were observed. IGF-II binding increased when cells were permeabilized with 0.01% digitonin, suggesting the presence of an intracellular receptor pool. Determined by Scatchard analysis and by polyacrylamide gel electrophoresis after affinity labeling, the higher binding was due solely to an increase in binding sites present on 220 kDa type II IGF receptors. In hepatocytes cultured at low densities, the number of cell surface receptors increased markedly, from 10-20,000 receptors per cell at a culture density of 6 X 10(5) cells/well to 70-80,000 receptors per cell at 0.38 X 10(5) cells/well. The increase was not due simply to the exposure of receptors from the intracellular pool, as a density-related increase in receptors was also seen in cells permeabilized with digitonin. There was no evidence that IGF binding proteins, either secreted by hepatocytes or present in fetal calf serum, had any effect on the measurement of receptor concentration or affinity. We conclude that rat hepatocytes in primary culture contain specific IGF-II receptors and that both cell surface and intracellular receptors are regulated by cell density

  17. A novel closed system bubble column photobioreactor for detailed characterisation of micro and macroalgal growth

    DEFF Research Database (Denmark)

    Holdt, Susan Løvstad; Christensen, L.; Iversen, J. J.L.

    Growth of the marine microalgae Tetraselmis striata Butcher and macroalgae Chondrus crispus Stackhouse was investigated in batch cultures in a closed system bubble column photobioreactor. A laboratory cultivation system was constructed that allowed on-line monitoring of temperature, pH and dissol......Growth of the marine microalgae Tetraselmis striata Butcher and macroalgae Chondrus crispus Stackhouse was investigated in batch cultures in a closed system bubble column photobioreactor. A laboratory cultivation system was constructed that allowed on-line monitoring of temperature, p...

  18. Comparison of human dermal fibroblasts (HDFs) growth rate in culture media supplemented with or without basic fibroblast growth factor (bFGF).

    Science.gov (United States)

    Abdian, Narges; Ghasemi-Dehkordi, Payam; Hashemzadeh-Chaleshtori, Morteza; Ganji-Arjenaki, Mahbobe; Doosti, Abbas; Amiri, Beheshteh

    2015-12-01

    Basic fibroblast growth factor (bFGF or FGF-2) is a member of the FGF family secreted by different kinds of cells like HDFs and it is an important nutritional factor for cell growth and differentiation. The HDFs release bFGF in culture media at very low. The present study aims to investigate the HDFs growth rate in culture media supplemented either with or without bFGF. In brief, HDFs were isolated from human foreskin sample and were cultured in vitro in media containing bFGF and lack of this factor. The cells growth rate was calculated by trypan blue. The karyotyping was performed using G-banding to investigate the chromosomal abnormality of HDFs in both groups. Total RNA of each groups were extracted and cDNA samples were synthesized then, real-time Q-PCR was used to measure the expression level of p27kip1 and cyclin D1 genes normalized to internal control gene (GAPDH). The karyotype analysis showed that HDFs cultured in media or without bFGF had normal karyotype (46 chromosomes, XY) and chromosomal abnormalities were not observed. The cell growth rates in both groups were normal with proliferated exponentially but the slope of growth curve in HDFs cultured in media containing bFGF was increased. Karyotyp test showed that bFGF does not affect on cytogenetic stability of cells. The survey of p27kip1 and cyclin D1 genes by real-time Q-PCR showed that the expression level of these genes were up-regulated when adding bFGF in culture media (p culture media with growth factor like bFGF could enhance the proliferation and differentiation capacity of cells and improve cells growth rate. Similarly, fibroblast growth factors did not induce any chromosomal abnormality in cells. Furthermore, in HDFs cultured in bFGF supplemented media, the p27kip1 and cyclin D1 genes were up-regulated and suggesting an important role for bFGF in cell-cycle regulation and progression and fibroblast division stimulation. It also suggests that the effects of bFGF on different cell types with

  19. Influence of flow conditions and matrix coatings on growth and differentiation of three-dimensionally cultured rat hepatocytes.

    Science.gov (United States)

    Fiegel, Henning C; Havers, Joerg; Kneser, Ulrich; Smith, Molly K; Moeller, Tim; Kluth, Dietrich; Mooney, David J; Rogiers, Xavier; Kaufmann, Peter M

    2004-01-01

    Maintenance of liver-specific function of hepatocytes in culture is still difficult. Improved culture conditions may enhance the cell growth and function of cultured cells. We investigated the effect of three-dimensional culture under flow conditions, and the influence of surface modifications in hepatocyte cultures. Hepatocytes were harvested from Lewis rats. Cells were cultured on three-dimensional polymeric poly-lactic-co-glycolic acid (PLGA) matrices in static culture, or in a pulsatile flow-bioreactor system. Different surface modifications of matrices were investigated: coating with collagen I, collagen IV, laminin, or fibronectin; or uncoated matrix. Hepatocyte numbers, DNA content, and albumin secretion rate were assessed over the observation period. Culture under flow condition significantly enhanced cell numbers. An additional improvement of this effect was observed, when matrix coating was used. Cellular function also showed a significant increase (4- to 5-fold) under flow conditions when compared with static culture. Our data showed that culture under flow conditions improves cell number, and strongly enhances cellular function. Matrix modification by coating with extracellular matrix showed overall an additive stimulatory effect. Our conclusion is that combining three-dimensional culture under flow conditions and using matrix modification significantly improves culture conditions and is therefore attractive for the development of successful culture systems for hepatocytes.

  20. Lactic Acid Bacterial Starter Culture with Antioxidant and γ-Aminobutyric Acid Biosynthetic Activities Isolated from Flatfish-Sikhae Fermentation.

    Science.gov (United States)

    Won, Yeong Geol; Yu, Hyun-Hee; Chang, Young-Hyo; Hwang, Han-Joon

    2015-12-01

    The aim of this study is to select a lactic acid bacterial strain as a starter culture for flatfish-Sikhae fermentation and to evaluate its suitability for application in a food system. Four strains of lactic acid bacteria isolated from commercial flatfish-Sikhae were identified and selected as starter culture candidates through investigation of growth rates, salt tolerance, food safety, and functional properties such as antioxidative and antimicrobial activities. The fermentation properties of the starter candidates were also examined in food systems prepared with these strains (candidate batch) in comparison with a spontaneous fermentation process without starter culture (control batch) at 15°C. The results showed that the candidate YG331 batch had better fermentation properties such as viable cell count, pH, and acidity than the other experimental batches, including the control batch. The results are expressed according to selection criteria based on a preliminary sensory evaluation and physiochemical investigation. Also, only a small amount of histamine was detected with the candidate YG331 batch. The radical scavenging activity of the candidate batches was better compared with the control batch, and especially candidate YG331 batch showed the best radical scavenging activity. Also, we isolated another starter candidate (identified as Lactobacillus brevis PM03) with γ-aminobutyric acid (GABA)-producing activity from commercial flatfish-Sikhae products. The sensory scores of the candidate YG331 batch were better than those of the other experimental batches in terms of flavor, color, and overall acceptance. In this study, we established selection criteria for the lactic acid bacterial starter for the flatfish-Sikhae production and finally selected candidate YG331 as the most suitable starter.

  1. Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base Controlled Ecological Life Support System (CELSS)

    Science.gov (United States)

    Venketeswaran, S.

    1987-01-01

    Experiments to determine whether plant tissue cultures can be grown in the presence of simulated lunar soil (SLS) and the effect of simulated lunar soil on the growth and morphogenesis of such cultures, as well as the effect upon the germination of seeds and the development of seedlings were carried out . Preliminary results on seed germination and seedling growth of rice and calli growth of winged bean and soybean indicate that there is no toxicity or inhibition caused by SLS. SLS can be used as a support medium with supplements of certain major and micro elements.

  2. Multiple shoot cultures of Atropa belladonna: Effect of physico-chemical factors on growth and alkaloid formation

    International Nuclear Information System (INIS)

    Benjamin, B.D.; Roja, P.C.; Heble, M.R.; Chandha, M.S.

    1987-01-01

    Multiple shoot cultures were established from shoot tip and axillary meristem of the plant Atropa belladonna. The cultures were initially raised on agar medium and subsequently maintained on liquid medium of Murashige and Skoog (1962) supplemented with BA. These cultures were subjected to different doses of -y-irradiation. Recovery from the radiation effects was observed in tissues subjected to 29 Gy during four successive passages. Plant growth regulators influenced the growth and morphogenetic events of the tissues. The precursors of tropane alkaloids marginally increased the alkaloid synthesis during the stationary phase of growth. Shoot cultures, established from different field grown plants varying in alkaloid content, were morphologically similar and did not exhibit the parental characteristics with respect to alkaloid formation

  3. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Eklöw, Annelie; Dalgaard, Paw

    2014-01-01

    Four mathematical models were developed and validated for simultaneous growth of mesophilic lactic acid bacteria from added cultures and Listeria monocytogenes, during chilled storage of cottage cheese with freshor cultured cream dressing. The mathematical models include the effect of temperature...... cheese to improvemodel performance. The inhibiting effect of mesophilic lactic acid bacteria from added cultures on growth of L. monocytogenes was efficiently modelled using the Jameson approach. The new models appropriately predicted the maximum population density of L. monocytogenes in cottage cheese......- and accuracy factors and with the concept of acceptable simulation zone. Evaluation of predicted growth rates of L. monocytogenes in cottage cheese with fresh- or cultured cream dressing resulted in bias-factors (Bf) of 1.07–1.10with corresponding accuracy factor (Af) values of 1.11 to 1.22. Lactic acid...

  4. NDA BATCH 2002-02

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  5. Growth of Leptospirillum ferriphilum in sulfur medium in co-culture with Acidithiobacillus caldus.

    Science.gov (United States)

    Smith, Sarah L; Johnson, D Barrie

    2018-03-01

    Leptospirillum ferriphilum and Acidithiobacillus caldus are both thermotolerant acidophilic bacteria that frequently co-exist in natural and man-made environments, such as biomining sites. Both are aerobic chemolithotrophs; L. ferriphilum is known only to use ferrous iron as electron donor, while A. caldus can use zero-valent and reduced sulfur, and also hydrogen, as electron donors. It has recently been demonstrated that A. caldus reduces ferric iron to ferrous when grown aerobically on sulfur. Experiments were carried out which demonstrated that this allowed L. ferriphilum to be sustained for protracted periods in media containing very little soluble iron, implying that dynamic cycling of iron occurred in aerobic mixed cultures of these two bacteria. In contrast, numbers of viable L. ferriphilum rapidly declined in mixed cultures that did not contain sulfur. Data also indicated that growth of A. caldus was partially inhibited in the presence of L. ferriphilum. This was shown to be due to greater sensitivity of the sulfur-oxidizer to ferric than to ferrous iron, and to highly positive redox potentials, which are characteristic of cultures containing Leptospirillum spp. The implications of these results in the microbial ecology of extremely acidic environments and in commercial bioprocessing applications are discussed.

  6. The Impact of Cultural and Sports Events upon the Growth of a Region

    Directory of Open Access Journals (Sweden)

    Daniel MOISE

    2015-08-01

    Full Text Available In this article, it is presented how cultural and sports events are benefic for the development of a region. Events that are promoted and organized in a proficient way can be regarded as real engines for the growth of a region, in terms of tourisms, services, and infrastructure and so on. The study will focus especially on cultural and sports events deployed in Romania, in different regions and the degree in which these events have influenced a region. In the first part of the paper, there are presented some important and drive efficient events, cultural and sports, that succeeded over the years in attracting bigger and bigger audiences, both from the region and from the country or district. The second part of the paper offers the results of a research conducted to see the perception of the inhabitants of such a region that flourishes due to the deployment of events and the degree of awareness of the benefits of hosting this kind of the events. And thirdly, we have drawn up some strategies that communities should follow in order to increase the popularity of their region.

  7. Feeder Cell Type Affects the Growth of In Vitro Cultured Bovine Trophoblast Cells

    Directory of Open Access Journals (Sweden)

    Islam M. Saadeldin

    2017-01-01

    Full Text Available Trophectoderm cells are the foremost embryonic cells to differentiate with prospective stem-cell properties. In the current study, we aimed at improving the current approach for trophoblast culture by using granulosa cells as feeders. Porcine granulosa cells (PGCs compared to the conventional mouse embryonic fibroblasts (MEFs were used to grow trophectoderm cells from hatched bovine blastocysts. Isolated trophectoderm cells were monitored and displayed characteristic epithelial/cuboidal morphology. The isolated trophectoderm cells expressed mRNA of homeobox protein (CDX2, cytokeratin-8 (KRT8, and interferon tau (IFNT. The expression level was higher on PGCs compared to MEFs throughout the study. In addition, primary trophectoderm cell colonies grew faster on PGCs, with a doubling time of approximately 48 hrs, compared to MEFs. PGCs feeders produced a fair amount of 17β-estradiol and progesterone. We speculated that the supplementation of sex steroids and still-unknown factors during the trophoblasts coculture on PGCs have helped to have better trophectoderm cell’s growth than on MEFs. This is the first time to use PGCs as feeders to culture trophectoderm cells and it proved superior to MEFs. We propose PGCs as alternative feeders for long-term culture of bovine trophectoderm cells. This model will potentially benefit studies on the early trophoblast and embryonic development in bovines.

  8. Effects of yeast polysaccharide on growth and flavonoid accumulation in Fagopyrum tataricum sprout cultures.

    Science.gov (United States)

    Zhao, Gang; Zhao, Jianglin; Peng, Lianxin; Zou, Liang; Wang, Jingbo; Zhong, Lingyun; Xiang, Dabing

    2012-09-25

    The purpose of this study was to investigate the effects of yeast polysaccharide (YPS) on growth and flavonoid accumulation in sprout cultures of Fagopyrum tataricum (tartary buckwheat). Without obvious change in the appearance of the sprouts, the exogenous YPS notably stimulated the production of functional metabolites in F. tataricum sprouts, and the stimulation effect was concentration-dependent. With 400 mg/L of YPS applied to the sprout cultures on day 6, the total rutin and quercentin content was effectively increased to 42.8 mg/gdw, or about 1.4-fold in comparison with the control of 31.2 mg/gdw. Feeding with 800 mg/L of YPS on day 9, the sprouts biomass was increased by about 8% compared to the control culture (0.99 gdw/100 sprouts versus 0.92 gdw/100 sprouts). Moreover, the present study revealed that the accumulation of these bioactive metabolites resulted from the stimulation of the phenylpropanoid pathway by YPS treatment. It could be an effective strategy for improving the functional quality of the F. tataricum sprouts provided with YPS.

  9. ANALYSIS OF GROWTH OF LALAWAK Barbonymus balleroides (VALENCIENNES, 1842 IN THREE CULTURE METHODS

    Directory of Open Access Journals (Sweden)

    Deni Radona

    2017-09-01

    Full Text Available In fish culture, optimal growth could be influenced by various culture methods. Aim of the study was to evaluate the productivity of Barbonymus balleroides, lalawak in floating net cages, concrete ponds, and earthen ponds. Cultivation was designed with the circulation water system. Experiment was conducted using completely randomized design with three treatments and three replications for each treatment. The experimental fish, sized of 4.20 ± 0.64 cm SL and weight of 2.14 ± 0.99 g, were obtained from induced breeding. The stocking density used was 20 individuals/m3. Fish were fed 3% of total weight two times every day using commercial pellet with 35% protein content for 90 day. The result showed that lalawak reared in earthen pond was no significant difference on length, weight, and biomass compared with that one in concrete pond (P>0.05, but significantly different (P0.05 among the three different culture systems for survival rate and FCR. Lalawak reared on earthen pond system supported with optimal water quality could increase productivity value.

  10. Growth of intestinal epithelium in organ culture is dependent on EGF signalling

    International Nuclear Information System (INIS)

    Abud, Helen E.; Watson, Nadine; Heath, Joan K.

    2005-01-01

    Differentiation of endoderm into intestinal epithelium is initiated at E13.5 of mouse development when there are significant changes in morphology resulting in the conversion of undifferentiated stratified epithelium into a mature epithelial monolayer. Here we demonstrate that monolayer formation is associated with the selective apoptosis of superficial cells lining the lumen while cell proliferation is progressively restricted to cells adjacent to the basement membrane. We describe an innovative embryonic gut culture system that maintains the three-dimensional architecture of gut and in which these processes are recapitulated in vitro. Explants taken from specific regions of the gut and placed into organ culture develop and express molecular markers (Cdx1, Cdx2 and A33 antigen) in the same spatial and temporal pattern observed in vivo indicating that regional specification is maintained. Inhibition of the epidermal growth factor receptor (EGFR) tyrosine kinase using the specific inhibitor AG1478 significantly reduced the proliferation and survival of cells within the epithelial cell layer of cultured gut explants. This demonstrates an essential role for the EGF signalling pathway during the early stages of intestinal development

  11. Growth factor-defined culture medium for human mesenchymal stem cells.

    Science.gov (United States)

    Mimura, Sumiyo; Kimura, Naohiro; Hirata, Mitsuhi; Tateyama, Daiki; Hayashida, Midori; Umezawa, Akihiro; Kohara, Arihiro; Nikawa, Hiroki; Okamoto, Tetsuji; Furue, Miho K

    2011-01-01

    Human bone marrow-derived mesenchymal stem cells (hMSCs) are potential cellular sources of therapeutic stem cells as they have the ability to proliferate and differentiate into a wide array of mesenchymal cell types such as osteoblasts, chondroblasts and adipocytes. hMSCs have been used clinically to treat patients with graft vs. host disease, osteogenesis imperfect, or alveolar cleft, suggesting that transplantation of hMSCs is comparatively safe as a stem cell-based therapy. However, conventional culture medium for hMSCs contains fetal bovine serum (FBS). In the present study, we developed a growth factor-defined, serum-free medium for culturing hMSCs. Under these conditions, TGF-beta1 promoted proliferation of hMSCs. The expanded hMSC population expressed the human pluripotency markers SSEA-3, -4, NANOG, OCT3/4 and SOX2. Furthermore, double positive cells for SSEA-3 and a mesenchymal cell marker, CD105, were detected in the population. The potential to differentiate into osteoblasts and adipocytes was confirmed. This work provides a useful tool to understand the basic biological properties of hMSCs in culture.

  12. Immunomodulatory and Growth-Promoting Potential of Lowcost Probiotic Product in Penaeus Monodon Culture System

    Directory of Open Access Journals (Sweden)

    Chandran Manohar Navin

    2017-06-01

    Full Text Available The capability of a low-cost probiotic product was evaluated in Penaeus monodon reared under an outdoor culture system for a period of 90 days. The low-cost probiotic product was formulated by mixing the broth culture of Bacillus cereus along with commercial chalk powder in 1:1 ratio. The prepared probiotic product as a powdered supplement was incorporated along with the shrimp diet at various concentrations (1 to 5%. The viability of B. cereus in the experimental diet was tested once in 30 days up to 90 days during the experimentation. After 90 days of feeding experiments, the growth performance of shrimp was determined with a maximum production of 11.98 ± 0.367 g, SGR of 5.030 ± 0.171% and FCE of 86.63 ± 1.300% in P. monodon fed D4 diet (4% probiotic supplement. The immunological parameters determined at the end of the culture experiment showed variation among diets. The total haemocyte count (273.66 ± 3.09 x 105 cells/ml, phenoloxidase activity (0.132 ± 0.007 OD and respiratory burst activity (0.291 ± 0.020 O.D were high in P. monodon fed D4 diet. Similar effects were observed for plasma protein concentration (68.00 ± 1.41 mg/ ml, lysozyme activity (0.483 ± 0.014 U/ml and bactericidal activity (81.0 ± 1.33% in shrimp fed D4 diet. The results of the present investigation conclude that the probiotic product at a concentration of 4% was effective in elevating the growth and immune performances in shrimp P. monodon.

  13. Proliferating fibroblasts and HeLa cells co-cultured in vitro reciprocally influence growth patterns, protein expression, chromatin features and cell survival.

    Science.gov (United States)

    Delinasios, John G; Angeli, Flora; Koumakis, George; Kumar, Shant; Kang, Wen-Hui; Sica, Gigliola; Iacopino, Fortunata; Lama, Gina; Lamprecht, Sergio; Sigal-Batikoff, Ina; Tsangaris, George T; Farfarelos, Christos D; Farfarelos, Maria C; Vairaktaris, Eleftherios; Vassiliou, Stavros; Delinasios, George J

    2015-04-01

    to identify biological interactions between proliferating fibroblasts and HeLa cells in vitro. Fibroblasts were isolated from both normal and tumour human tissues. Coverslip co-cultures of HeLa and fibroblasts in various ratios with medium replacement every 48 h were studied using fixed cell staining with dyes such as Giemsa and silver staining, with immunochemistry for Ki-67 and E-cadherin, with dihydrofolate reductase (DHFR) enzyme reaction, as well as live cell staining for non-specific esterases and lipids. Other techniques included carmine cell labeling, autoradiography and apoptosis assessment. Under conditions of feeding and cell: cell ratios allowing parallel growth of human fibroblasts and HeLa cells, co-cultured for up to 20 days, a series of phenomena occur consecutively: profound affinity between the two cell types and exchange of small molecules; encircling of the HeLa colonies by the fibroblasts and enhanced growth of both cell types at their contact areas; expression of carbonic anhydrase in both cell types and high expression of non-specific esterases and cytoplasmic argyrophilia in the surrounding fibroblasts; intense production and secretion of lipid droplets by the surrounding fibroblasts; development of a complex net of argyrophilic projections of the fibroblasts; E-cadherin expression in the HeLa cells; from the 10th day onwards, an increasing detachment of batches of HeLa cells at the peripheries of colonies and appearance of areas with many multi-nucleated and apoptotic HeLa cells, and small HeLa fragments; from the 17th day, appearance of fibroblasts blocked at the G2-M phase. Co-cultures at approximately 17-20 days display a cell-cell fight with foci of (a) sparse growth of both cell types, (b) overgrowth of the fibroblasts and (c) regrowth of HeLa in small colonies. These results indicate that during their interaction with HeLa cells in vitro, proliferating fibroblasts can be activated against HeLa. This type of activation is not observed

  14. Light sources and culture media in the in vitro growth of the Brazilian orchid Microlaelia lundii

    Directory of Open Access Journals (Sweden)

    Vanessa Favetta

    2017-08-01

    Full Text Available The Brazilian micro-orchid Microlaelia lundii enchants by its beautiful blooms in winter, but its cultivation is still a challenge, requiring specific care. The objectiv of this work was to evaluate the influence of light sources and culture media on in vitro growth and ex vitro survival of this micro-orchid. M. lundii seedlings were transferred to flasks containing the culture medium ½ MS and Simplified Medium, consisting of 5 mL L-1 of Biofert Plus® NPK fertilizer (09-08-09 and 60 g L-1 of ‘Nanica’ banana pulp. These flasks were placed in a growth chamber composed of seven environments, characterized by types of lighting: L1 LEDtube 4000K; L2 LEDtube 6500K; L3 L1 + L2; L4 L1 + L1; L5 red LED; L6 blue LED; L7 fluorescent lamp (control. After 200 days of cultivation, biometric growth parameters and leaves chlorophyll content were evaluated together with the percentage of seedling survival when acclimatized. At the end of the experiment, an analysis of individual variances and a combined analysis of the environments were carried out. The simplified medium led to higher seedlings, especially for light source L6. Light sources L1, L2, L3 and L4 promoted an increase in the seedlings root system in the simplified medium. As for the chlorophyll content, L4 and L7 showed higher contents of chlorophyll a and b. The simplified medium led practically to 100% of seedling survival, regardless of the light source used. Results shown that the simplified medium for light sources L1, L2, L3 and L4 is recommended for the in vitro propagation of M. lundii.

  15. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese.

    Science.gov (United States)

    Østergaard, Nina Bjerre; Eklöw, Annelie; Dalgaard, Paw

    2014-10-01

    Four mathematical models were developed and validated for simultaneous growth of mesophilic lactic acid bacteria from added cultures and Listeria monocytogenes, during chilled storage of cottage cheese with fresh- or cultured cream dressing. The mathematical models include the effect of temperature, pH, NaCl, lactic- and sorbic acid and the interaction between these environmental factors. Growth models were developed by combining new and existing cardinal parameter values. Subsequently, the reference growth rate parameters (μref at 25°C) were fitted to a total of 52 growth rates from cottage cheese to improve model performance. The inhibiting effect of mesophilic lactic acid bacteria from added cultures on growth of L. monocytogenes was efficiently modelled using the Jameson approach. The new models appropriately predicted the maximum population density of L. monocytogenes in cottage cheese. The developed models were successfully validated by using 25 growth rates for L. monocytogenes, 17 growth rates for lactic acid bacteria and a total of 26 growth curves for simultaneous growth of L. monocytogenes and lactic acid bacteria in cottage cheese. These data were used in combination with bias- and accuracy factors and with the concept of acceptable simulation zone. Evaluation of predicted growth rates of L. monocytogenes in cottage cheese with fresh- or cultured cream dressing resulted in bias-factors (Bf) of 1.07-1.10 with corresponding accuracy factor (Af) values of 1.11 to 1.22. Lactic acid bacteria from added starter culture were on average predicted to grow 16% faster than observed (Bf of 1.16 and Af of 1.32) and growth of the diacetyl producing aroma culture was on average predicted 9% slower than observed (Bf of 0.91 and Af of 1.17). The acceptable simulation zone method showed the new models to successfully predict maximum population density of L. monocytogenes when growing together with lactic acid bacteria in cottage cheese. 11 of 13 simulations of L

  16. Yearly growth and metabolic changes in earthen pond-cultured meagre Argyrosomus regius

    Directory of Open Access Journals (Sweden)

    Luis Vargas-Chacoff

    2014-06-01

    Full Text Available Metabolic modifications associated with natural environmental conditions were assessed in the meagre Argyrosomus regius cultured in earthen ponds under natural photoperiod and temperature. Juvenile specimens (90-100 g initial weight were sampled (plasma, liver and muscle every two months for 18 months (between December 2004 and May 2006. Specimens showed seasonal variations in growth rate, with the highest values in spring and summer. Plasmatic, hepatic and muscular metabolite levels and hepatic and muscular metabolic enzymes also showed significant variations throughout the year. Enzymatic activity related to carbohydrate metabolism in the liver (HK, FBPase and G6PDH showed great modifications in summer, increasing glycogenogenic pathways, while amino acid metabolism (GDH and GOT activity was enhanced in spring and summer. However lipid-related (G3PDH activity metabolic enzymes did not show a clear seasonal pattern. In muscle, enzymatic activity related to amino acid, lipid and lactate metabolism (LDH-O activity, but not carbohydrate metabolism, showed seasonal changes in parallel with changes in growth rate. Thus A. regius specimens showed a trend to grow in summer months and mobilize their energy reserves in winter. Differences in the hepatic level were observed between the first and the second year of the study, suggesting the possible existence of metabolic changes related to specimen age or size. Our results indicate that growth and metabolic responses in A. regius are environmentally dependent and that this species is a very good candidate for diversification in aquaculture.

  17. Biofouling leads to reduced shell growth and flesh weight in the cultured mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Sievers, Michael; Fitridge, Isla; Dempster, Tim; Keough, Michael J

    2013-01-01

    Competitive interactions between cultured mussels and fouling organisms may result in growth and weight reductions in mussels, and compromised aquaculture productivity. Mussel ropes were inoculated with Ciona intestinalis, Ectopleura crocea or Styela clava, and growth parameters of fouled and unfouled Mytilus galloprovincialis were compared after two months. Small mussels (≈ 50 mm) fouled by C. intestinalis and E. crocea were 4.0 and 3.2% shorter in shell length and had 21 and 13% reduced flesh weight, respectively, compared to the controls. Large mussels (≈ 68 mm) fouled by S. clava, C. intestinalis and E. crocea were 4.4, 3.9 and 2.1% shorter than control mussels, respectively, but flesh weights were not significantly reduced. A series of competitive feeding experiments indicated that S. clava and C. intestinalis did not reduce mussels' food consumption, but that E. crocea, through interference competition, did. Fouling by these species at the densities used here reduced mussel growth and flesh weight, likely resulting in economic losses for the industry, and requires consideration when developing biofouling mitigation strategies.

  18. Growth-promoting effect on iron-sulfur proteins on axenic cultures of Entamoeba dispar

    Directory of Open Access Journals (Sweden)

    Khalifa S.A.M.

    2006-03-01

    Full Text Available A growth-promoting factor (GPF that promotes the growth of Entamoeba dispar under axenic culture conditions was found in fractions of mitochondria (Mt, hydrogenosomes (Hg and chloroplasts (Cp obtained from cells of six different protozoan, mammalian and plant species. We were able to extract the GPF from the Cp-rich leaf cells of a plant (spiderwort: Commelina communis L. in an acetone-soluble fraction as a complex of chlorophyll with low molecular weight proteins (molecular weight [MW] approximately 4,600. We also found that on treatment with 0.6 % complexes of 2-mercapthoethanol (2ME, complexes of chlorophyll-a with iron-sulphur (Fe-S proteins (e.g., ferredoxins [Fd] from spinach and Clostridium pasteurianum and noncomplex rubredoxin (Rd from C. pasteurianum have a growth-promoting effect on E. dispar. These findings suggest that E. dispar may lack a sufficient quantity of some essential components of Fe-S proteins, such as Fe-S center.

  19. Specific binding sites for growth hormone in cultured mouse thymic epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Ban, E.; Haour, F. (Institut Pasteur, Paris (France)); Gagnerault, M.; Dardenne, M.; Postel-Vinay, M. (Hopital Necker, Paris (France)); Jammes, H. (Endocrinologie Molecuaire, INRA, Jouy-en-Josas (France))

    1991-01-01

    Growth hormones bound specifically to murine thymic epithelial cells, which represent the major component of thymic micro-environment and can be modulated by pituitary hormones. The Kds found with human growth hormone and bovine growth hormone were 0.14 and 0.27 nM with a Bmax 0.56 and 0.35 fmol/10{sup 6} cells respectively. Competition experiment analysis showed ED{sub 50} of 0.24 nM for hGH, 0.46 nM for rGH, 0.71 nM for bGH, 11.8 nM for hPRL and 11.2 nM for oPRL. No specific binding of ({sup 125}I)-oPRL was observed under the same conditions. Both hPRL and bGH showed a negative regulatory effect on the number of the hGH binding sites when incubated with the culture for three days. The presence of GH receptors on thymic epithelial cells provides biochemical evidence for the effect of GH on thymic function.

  20. 3D cell culture systems modeling tumor growth determinants in cancer target discovery.

    Science.gov (United States)

    Thoma, Claudio R; Zimmermann, Miriam; Agarkova, Irina; Kelm, Jens M; Krek, Wilhelm

    2014-04-01

    Phenotypic heterogeneity of cancer cells, cell biological context, heterotypic crosstalk and the microenvironment are key determinants of the multistep process of tumor development. They sign responsible, to a significant extent, for the limited response and resistance of cancer cells to molecular-targeted therapies. Better functional knowledge of the complex intra- and intercellular signaling circuits underlying communication between the different cell types populating a tumor tissue and of the systemic and local factors that shape the tumor microenvironment is therefore imperative. Sophisticated 3D multicellular tumor spheroid (MCTS) systems provide an emerging tool to model the phenotypic and cellular heterogeneity as well as microenvironmental aspects of in vivo tumor growth. In this review we discuss the cellular, chemical and physical factors contributing to zonation and cellular crosstalk within tumor masses. On this basis, we further describe 3D cell culture technologies for growth of MCTS as advanced tools for exploring molecular tumor growth determinants and facilitating drug discovery efforts. We conclude with a synopsis on technological aspects for on-line analysis and post-processing of 3D MCTS models. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Growth characteristics of liquid cultures increase the reliability of presumptive identification of Mycobacterium tuberculosis complex.

    Science.gov (United States)

    Pinhata, Juliana Maira Watanabe; Felippe, Isis Moreira; Gallo, Juliana Failde; Chimara, Erica; Ferrazoli, Lucilaine; de Oliveira, Rosangela Siqueira

    2018-04-23

    We evaluated the microscopic and macroscopic characteristics of mycobacteria growth indicator tube (MGIT) cultures for the presumptive identification of the Mycobacterium tuberculosis complex (MTBC) and assessed the reliability of this strategy for correctly directing isolates to drug susceptibility testing (DST) or species identification. A total of 1526 isolates of mycobacteria received at the Instituto Adolfo Lutz were prospectively subjected to presumptive identification by the observation of growth characteristics along with cord formation detection via microscopy. The presumptive identification showed a sensitivity, specificity and accuracy of 98.8, 92.5 and 97.9 %, respectively. Macroscopic analysis of MTBC isolates that would have been erroneously classified as non-tuberculous mycobacteria based solely on microscopic morphology enabled us to direct them rapidly to DST, representing a substantial gain to patients. In conclusion, the growth characteristics of mycobacteria in MGIT, when considered along with cord formation, increased the reliability of the presumptive identification, which has a great impact on the laboratory budget and turnaround times.

  2. Specific binding sites for growth hormone in cultured mouse thymic epithelial cells

    International Nuclear Information System (INIS)

    Ban, E.; Haour, F.; Gagnerault, M.; Dardenne, M.; Postel-Vinay, M.; Jammes, H.

    1991-01-01

    Growth hormones bound specifically to murine thymic epithelial cells, which represent the major component of thymic micro-environment and can be modulated by pituitary hormones. The Kds found with human growth hormone and bovine growth hormone were 0.14 and 0.27 nM with a Bmax 0.56 and 0.35 fmol/10 6 cells respectively. Competition experiment analysis showed ED 50 of 0.24 nM for hGH, 0.46 nM for rGH, 0.71 nM for bGH, 11.8 nM for hPRL and 11.2 nM for oPRL. No specific binding of ( 125 I)-oPRL was observed under the same conditions. Both hPRL and bGH showed a negative regulatory effect on the number of the hGH binding sites when incubated with the culture for three days. The presence of GH receptors on thymic epithelial cells provides biochemical evidence for the effect of GH on thymic function

  3. Metabolomic Profiling of 13 Diatom Cultures and Their Adaptation to Nitrate-Limited Growth Conditions.

    Directory of Open Access Journals (Sweden)

    Mariusz A Bromke

    Full Text Available Diatoms are very efficient in their use of available nutrients. Changes in nutrient availability influence the metabolism and the composition of the cell constituents. Since diatoms are valuable candidates to search for oil producing algae, measurements of diatom-produced compounds can be very useful for biotechnology. In order to explore the diversity of lipophilic compounds produced by diatoms, we describe the results from an analysis of 13 diatom strains. With the help of a lipidomics platform, which combines an UPLC separation with a high resolution/high mass accuracy mass spectrometer, we were able to measure and annotate 142 lipid species. Out of these, 32 were present in all 13 cultures. The annotated lipid features belong to six classes of glycerolipids. The data obtained from the measurements were used to create lipidomic profiles. The metabolomic overview of analysed cultures is amended by the measurement of 96 polar compounds. To further increase the lipid diversity and gain insight into metabolomic adaptation to nitrogen limitation, diatoms were cultured in media with high and low concentrations of nitrate. The growth in nitrogen-deplete or nitrogen-replete conditions affects metabolite accumulation but has no major influence on the species-specific metabolomic profile. Thus, the genetic component is stronger in determining metabolic patterns than nitrogen levels. Therefore, lipid profiling is powerful enough to be used as a molecular fingerprint for diatom cultures. Furthermore, an increase of triacylglycerol (TAG accumulation was observed in low nitrogen samples, although this trend was not consistent across all 13 diatom strains. Overall, our results expand the current understanding of metabolomics diversity in diatoms and confirm their potential value for producing lipids for either bioenergy or as feed stock.

  4. Metabolomic Profiling of 13 Diatom Cultures and Their Adaptation to Nitrate-Limited Growth Conditions

    Science.gov (United States)

    Bromke, Mariusz A.; Sabir, Jamal S.; Alfassi, Fahad A.; Hajarah, Nahid H.; Kabli, Saleh A.; Al-Malki, Abdulrahman L.; Ashworth, Matt P.; Méret, Michaël; Jansen, Robert K.; Willmitzer, Lothar

    2015-01-01

    Diatoms are very efficient in their use of available nutrients. Changes in nutrient availability influence the metabolism and the composition of the cell constituents. Since diatoms are valuable candidates to search for oil producing algae, measurements of diatom-produced compounds can be very useful for biotechnology. In order to explore the diversity of lipophilic compounds produced by diatoms, we describe the results from an analysis of 13 diatom strains. With the help of a lipidomics platform, which combines an UPLC separation with a high resolution/high mass accuracy mass spectrometer, we were able to measure and annotate 142 lipid species. Out of these, 32 were present in all 13 cultures. The annotated lipid features belong to six classes of glycerolipids. The data obtained from the measurements were used to create lipidomic profiles. The metabolomic overview of analysed cultures is amended by the measurement of 96 polar compounds. To further increase the lipid diversity and gain insight into metabolomic adaptation to nitrogen limitation, diatoms were cultured in media with high and low concentrations of nitrate. The growth in nitrogen-deplete or nitrogen-replete conditions affects metabolite accumulation but has no major influence on the species-specific metabolomic profile. Thus, the genetic component is stronger in determining metabolic patterns than nitrogen levels. Therefore, lipid profiling is powerful enough to be used as a molecular fingerprint for diatom cultures. Furthermore, an increase of triacylglycerol (TAG) accumulation was observed in low nitrogen samples, although this trend was not consistent across all 13 diatom strains. Overall, our results expand the current understanding of metabolomics diversity in diatoms and confirm their potential value for producing lipids for either bioenergy or as feed stock. PMID:26440112

  5. Metabolic responses and pathway changes of mammalian cells under different culture conditions with media supplementations.

    Science.gov (United States)

    Park, Seo-Young; Reimonn, Thomas M; Agarabi, Cyrus D; Brorson, Kurt A; Yoon, Seongkyu

    2018-02-21

    Amino acids and glucose consumption, cell growth and monoclonal antibody (mAb) production in mammalian cell culture are key considerations during upstream process and particularly media optimization. Understanding the interrelations and the relevant cellular physiology will provide insight for setting strategy of robust and effective mAb production. The aim of this study was to further our understanding of nutrient consumption metabolism, since this could have significant impact on enhancing mAb titer, cell proliferation, designing feeding strategies, and development of feed media. The nutrient consumption pattern, mAb concentration, and cell growth were analyzed in three sets of cell cultures with media supplementation of glucose, methionine, threonine, tryptophan, and tyrosine. The amino acids metabolism and its impact on cell growth and mAb production during the batch and fed-batch culture were closely analyzed. It was shown that the phenylalanine, tyrosine and tryptophan biosynthesis pathways were significantly altered under different culture conditions with different media. These changes were more apparent in the fed-batch process in which higher mAb titer was observed due to the metabolic changes than mAb titer in the batch process. The pathway analysis approach was well utilized for evaluating the impact on the relevant pathways involved under different cell culture conditions to improve cell growth and mAb titer. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  6. NGBAuth - Next Generation Batch Authentication for long running batch jobs.

    CERN Document Server

    Juto, Zakarias

    2015-01-01

    This document describes the prototyping of a new solution for the CERN batch authentication of long running jobs. While the job submission requires valid user credentials, these have to be renewed due to long queuing and execution times. Described within is a new system which will guarantee a similar level of security as the old LSFAuth while simplifying the implementation and the overall architecture. The new system is being built on solid, streamlined and tested components (notably OpenSSL) and a priority has been to make it more generic in order to facilitate the evolution of the current system such as for the expected migration from LSF to Condor as backend batch system.

  7. Optimization of Culture Medium for the Growth of Candida sp. and Blastobotrys sp. as Starter Culture in Fermentation of Cocoa Beans (Theobroma cacao) Using Response Surface Methodology (RSM).

    Science.gov (United States)

    Mahazar, N H; Zakuan, Z; Norhayati, H; MeorHussin, A S; Rukayadi, Y

    2017-01-01

    Inoculation of starter culture in cocoa bean fermentation produces consistent, predictable and high quality of fermented cocoa beans. It is important to produce healthy inoculum in cocoa bean fermentation for better fermented products. Inoculum could minimize the length of the lag phase in fermentation. The purpose of this study was to optimize the component of culture medium for the maximum cultivation of Candida sp. and Blastobotrys sp. Molasses and yeast extract were chosen as medium composition and Response Surface Methodology (RSM) was then employed to optimize the molasses and yeast extract. Maximum growth of Candida sp. (7.63 log CFU mL-1) and Blastobotrys sp. (8.30 log CFU mL-1) were obtained from the fermentation. Optimum culture media for the growth of Candida sp., consist of 10% (w/v) molasses and 2% (w/v) yeast extract, while for Blastobotrys sp., were 1.94% (w/v) molasses and 2% (w/v) yeast extract. This study shows that culture medium consists of molasses and yeast extract were able to produce maximum growth of Candida sp. and Blastobotrys sp., as a starter culture for cocoa bean fermentation.

  8. Improved growth media and culture techniques for genetic analysis and assessment of biomass utilization by Caldicellulosiruptor bescii.

    Science.gov (United States)

    Farkas, Joel; Chung, Daehwan; Cha, Minseok; Copeland, Jennifer; Grayeski, Philip; Westpheling, Janet

    2013-01-01

    Methods for efficient growth and manipulation of relatively uncharacterized bacteria facilitate their study and are essential for genetic manipulation. We report new growth media and culture techniques for Caldicellulosiruptor bescii, the most thermophilic cellulolytic bacterium known. A low osmolarity defined growth medium (LOD) was developed that avoids problems associated with precipitates that form in previously reported media allowing the monitoring of culture density by optical density at 680 nm (OD(680)) and more efficient DNA transformation by electroporation. This is a defined minimal medium and does not support growth when a carbon source is omitted, making it suitable for selection of nutritional markers as well as the study of biomass utilization by C. bescii. A low osmolarity complex growth medium (LOC) was developed that dramatically improves growth and culture viability during storage, making it a better medium for routine growth and passaging of C. bescii. Both media contain significantly lower solute concentration than previously published media, allowing for flexibility in developing more specialized media types while avoiding the issues of growth inhibition and cell lysis due to osmotic stress. Plating on LOD medium solidified by agar results in ~1,000-fold greater plating efficiency than previously reported and allows the isolation of discrete colonies. These new media represent a significant advance for both genetic manipulation and the study of biomass utilization in C. bescii, and may be applied broadly across the Caldicellulosiruptor genus.

  9. Growth of sweetpotato cultured in the newly designed hydroponic system for space farming

    Science.gov (United States)

    Kitaya, Y.; Hirai, H.; Wei, X.; Islam, A. F. M. S.; Yamamoto, M.

    Life support of crews in long-duration space missions for other planets will be highly dependent on amounts of food, atmospheric O2 and clean water produced by plants. Therefore, the space farming system with scheduling of crop production, obtaining high yields with a rapid turnover rate, converting atmospheric CO2 to O2 and purifying water should be established with employing suitable plant species and cultivars and precisely controlling environmental variables around plants grown at a high density in a limited space. In this study, we developed a new hydroponic method for producing tuberous roots and fresh edible leaves and stems of sweetpotato. In the first experiment, we examined the effects of water contents in the rooting substrate on growth and tuberous root development of sweetpotato. The rooting substrates made with rockwool slabs were inclined in a culture container and absorbed nutrient solution from the lower end of the slabs by capillary action. Tuberous roots developed on the lower surface of the rockwool slabs. The tuberous roots showed better growth and development at locations farther from the water surface on the rockwool slabs, which had lower water content. In the second experiment, three sweetpotato cultivars were cultured in a hydroponic system for five months from June to November under the sun light in Osaka, Japan as a fundamental study for establishing the space farming system. The cultivars employed were ‘Elegant summer’, ‘Kokei-14’ and ‘Beniazuma’. The hydroponic system mainly consisted of culture containers and rockwool slabs. Dry weights of tuberous roots developed in the aerial space between the rockwool slab and the nutrient solution filled at the bottom of the culture container were 0.34, 0.45 and 0.23 kg/plant and dry weights of the top portion (leaves, petioles and stems) were 0.42, 0.29 and 0.61 kg/plant for ‘Elegant summer’, ‘Kokei-14’ and ‘Beniazuma’, respectively. Young stems and leaves as well as

  10. Chlorpyrifos exerts opposing effects on axonal and dendritic growth in primary neuronal cultures

    International Nuclear Information System (INIS)

    Howard, Angela S.; Bucelli, Robert; Jett, David A.; Bruun, Donald; Yang, Dongren; Lein, Pamela J.

    2005-01-01

    Evidence that children are widely exposed to organophosphorus pesticides (OPs) and that OPs cause developmental neurotoxicity in animal models raises significant concerns about the risks these compounds pose to the developing human nervous system. Critical to assessing this risk is identifying specific neurodevelopmental events targeted by OPs. Observations that OPs alter brain morphometry in developing rodents and inhibit neurite outgrowth in neural cell lines suggest that OPs perturb neuronal morphogenesis. However, an important question yet to be answered is whether the dysmorphogenic effect of OPs reflects perturbation of axonal or dendritic growth. We addressed this question by quantifying axonal and dendritic growth in primary cultures of embryonic rat sympathetic neurons derived from superior cervical ganglia (SCG) following in vitro exposure to chlorpyrifos (CPF) or its metabolites CPF-oxon (CPFO) and trichloropyridinol (TCP). Axon outgrowth was significantly inhibited by CPF or CPFO, but not TCP, at concentrations ≥0.001 μM or 0.001 nM, respectively. In contrast, all three compounds enhanced BMP-induced dendritic growth. Acetylcholinesterase was inhibited only by the highest concentrations of CPF (≥1 μM) and CPFO (≥1 nM); TCP had no effect on this parameter. In summary, these compounds perturb neuronal morphogenesis via opposing effects on axonal and dendritic growth, and both effects are independent of acetylcholinesterase inhibition. These findings have important implications for current risk assessment practices of using acetylcholinesterase inhibition as a biomarker of OP neurotoxicity and suggest that OPs may disrupt normal patterns of neuronal connectivity in the developing nervous system

  11. Exponential fed-batch strategy for enhancing biosurfactant production by Bacillus subtilis.

    Science.gov (United States)

    Amin, G A

    2014-01-01

    Surfactin produced by Bacillus subtilis BDCC-TUSA-3 from Maldex-15 was used as a growth-associated product in a conventional batch process. Maldex-15 is a cheap industrial by-product recovered during manufacturing of high fructose syrup from corn starch. Surfactin production was greatly improved in exponential fed-batch fermentation. Maldex-15 and other nutrients were exponentially fed into the culture based on the specific growth rate of the bacterium. In order to maximize surfactin yield and productivity, conversion of different quantities of Maldex-15 into surfactin was investigated in five different fermentation runs. In all runs, most of the Maldex-15 was consumed and converted into surfactin and cell biomass with appreciable efficiencies. The best results were obtained with the fermentation run supplied with 204 g Maldex-15. Up to 36.1 g l(-1) of surfactin and cell biomass of 31.8 g l(-1) were achieved in 12 h. Also, a marked substrate yield of 0.272 g g(-1) and volumetric reactor productivity of 2.58 g 1(-1) h(-1) were obtained, confirming the establishment of a cost-effective commercial surfactin production.

  12. Molecular Mechanisms Contributing to the Growth and Physiology of an Extremophile Cultured with Dielectric Heating.

    Science.gov (United States)

    Cusick, Kathleen D; Lin, Baochuan; Malanoski, Anthony P; Strycharz-Glaven, Sarah M; Cockrell-Zugell, Allison; Fitzgerald, Lisa A; Cramer, Jeffrey A; Barlow, Daniel E; Boyd, Thomas J; Biffinger, Justin C

    2016-10-15

    The effect of microwave frequency electromagnetic fields on living microorganisms is an active and highly contested area of research. One of the major drawbacks to using mesophilic organisms to study microwave radiation effects is the unavoidable heating of the organism, which has limited the scale (60°C). This study identified changes in global gene expression profiles during the growth of Thermus scotoductus SA-01 at 65°C using dielectric (2.45 GHz, i.e., microwave) heating. RNA sequencing was performed on cultures at 8, 14, and 24 h after inoculation to determine the molecular mechanisms contributing to long-term cellular growth and survival under microwave heating conditions. Over the course of growth, genes associated with amino acid metabolism, carbohydrate metabolism, and defense mechanisms were upregulated; the number of repressed genes with unknown function increased; and at all time points, transposases were upregulated. Genes involved in cell wall biogenesis and elongation were also upregulated, consistent with the distinct elongated cell morphology observed after 24 h using microwave heating. Analysis of the global differential gene expression data enabled the identification of molecular processes specific to the response of T. scotoductus SA-01 to dielectric heating during growth. The residual heating of living organisms in the microwave region of the electromagnetic spectrum has complicated the identification of radiation-only effects using microorganisms for 50 years. A majority of the previous experiments used either mature cells or short exposure times with low-energy high-frequency radiation. Using global differential gene expression data, we identified molecular processes unique to dielectric heating using Thermus scotoductus SA-01 cultured over 30 h in a commercial microwave digestor. Genes associated with amino acid metabolism, carbohydrate metabolism, and defense mechanisms were upregulated; the number of repressed genes with unknown

  13. Fate of amoxicillin in mixed-culture bioreactors and its effects on microbial growth and resistance to silver ions.

    Science.gov (United States)

    Cunningham, James H; Lin, Lian-Shin

    2010-03-01

    This research focused on studying the fate of amoxicillin (AMX) in mixed-culture bioreactors and its effects on bacterial growth and bacterial resistance to silver-ion disinfection. The bioreactors were dosed with a range of AMX (10-70 mg L(-1) d(-1)) mimicking a biological treatment unit of a proposed water recovery system for long-term space missions. Aqueous-phase AMX concentrations in the bioreactors were monitored to characterize the kinetics of selected AMX fate processes. Specific growth rates and silver minimum effective concentrations (MECs) of the bacterial cultures were determined by assessing cell viability using flow cytometry. Hydrolysis, sorption, and biodegradation of AMX followed first-order kinetics with rate constants of 0.078, 0.083, and 0.13 d(-1), respectively. Specific growth rates of the AMX-dosed cultures were suppressed from 7% to 35% in order of increasing AMX dose as compared to the AMX-free control cultures. The AMX-treated cultures had higher silver MECs than the AMX-free control cultures, indicating an enhanced bacterial resistance to silver ions as a result of the AMX exposure. Biosorption experiments revealed that the AMX-treated cultures exhibited exclusion of silver ions from the cells as a potential mechanism for the enhanced resistance. This paper reports for the first time that low levels of AMX (<100 mg L(-1)) could induce bacterial cross-resistance to silver ion in an aqueous system mimicking an active biological system for wastewater treatment.

  14. Analysis of single hyphal growth and fragmentation in submerged cultures using a population model

    DEFF Research Database (Denmark)

    Krabben, Preben; Nielsen, Søren; Michelsen, Michael Locht

    1997-01-01

    Descriptions of population dynamics in submerged cultures are important when studying the mechanisms of growth and fragmentation of filamentous microorganisms. Population models are traditionally formulated as population balance equations. Population models of filamentous morphology are difficult...... to solve because of random fragmentation, which introduces an integral term into the population balance equations. Balances for the systemic properties, e.g. concentration of hyphal elements, substrate concentration, average total hyphal length, and average number of growing tips, are set up. Based...... on these balances one can solve the inverse problem, i.e. determination of kinetic parameters directly from measurements of the hyphal morphology. Both a Monte Carlo method and a discretization method have been used to calculate the steady-state population distribution. The two methods are compared and the Monte...

  15. Nitrogen balancing and xylose addition enhances growth capacity and protein content in Chlorella minutissima cultures.

    Science.gov (United States)

    Freitas, B C B; Esquível, M G; Matos, R G; Arraiano, C M; Morais, M G; Costa, J A V

    2016-10-01

    This study aimed to examine the metabolic changes in Chlorella minutissima cells grown under nitrogen-deficient conditions and with the addition of xylose. The cell density, maximum photochemical efficiency, and chlorophyll and lipid levels were measured. The expression of two photosynthetic proteins, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the beta subunit (AtpB) of adenosine triphosphate synthase, were measured. Comparison of cells grown in medium with a 50% reduction in the nitrogen concentration versus the traditional medium solution revealed that the cells grown under nitrogen-deficient conditions exhibited an increased growth rate, higher maximum cell density (12.7×10(6)cellsmL(-1)), optimal PSII efficiency (0.69) and decreased lipid level (25.08%). This study has taken the first steps toward protein detection in Chlorella minutissima, and the results can be used to optimize the culturing of other microalgae. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Antisera production to detect indoleacetic acid in cultures of plant-growth promoting bacteria

    International Nuclear Information System (INIS)

    Rojas, Marcia M; Hernandez, Annia; Rives, Narovis; Tejera, Berto; Acebo, Yanelis; Heydrich, Mayra

    2012-01-01

    Rabbit polyclonal antisera against indoleacetic acid (IAA) bound to nitrocellulose membrane were obtained, which exhibited a high titer and specificity. The dot immunobinding technique with colloidal gold was used to detect auxin production by several strains belonging to Gluconacetobacter, Herbaspirillum, Azospirillum, Pseudomonas, Burkholderia and Bacillus genera, using culture supernatants as antigens. Moreover, auxin production was quantified by the Salkowski's method to corroborate the previous results. It was found that that all the studied microorganisms produce IAA and the feasibility of using these antisera to detect the metabolite was confirmed. Taking into account the potentialities of plant growth promoting bacteria as biofertilizers, the use of these antisera for a rapid and easy detection of IAA in bacteria associated with important crops is thus recommended.

  17. Growth of human T lymphocyte colonies from whole blood: culture requirements and applications

    International Nuclear Information System (INIS)

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.

    1982-01-01

    Growth of human lymphocyte colonies from whole blood following stimulation with PHA, Con A, or PPD is described. Individual colony cells were identified as T lymphocytes on the basis of surface marker and enzyme cytochemical characterizations. Colony formation increased as a power function over a wide range of cell concentrations above a critical minimal concentration. The whole blood culture system eliminates possible selective effects of lymphocyte colony techniques utilizing gradient-enriched lymphocyte fractions and more closely approximates the in vivo milieu. The whole blood colony method is more sensitive for the detection of low-level radiation effects on lymphocytes than widely used tests that measure 3 H-thymidine incorporation. In preliminary studies, researchers used the whole blood method to determine the relative radiosensitivity of lymphocytes from humans with various hematopoietic disorders, and observed abnormalities in mitogen responsiveness and colony formation in some of the patient groups. This method has wide application for studies in cellular and clinical immunology

  18. Bifurcations of a periodically forced microbial continuous culture model with restrained growth rate

    Science.gov (United States)

    Ren, Jingli; Yuan, Qigang

    2017-08-01

    A three dimensional microbial continuous culture model with a restrained microbial growth rate is studied in this paper. Two types of dilution rates are considered to investigate the dynamic behaviors of the model. For the unforced system, fold bifurcation and Hopf bifurcation are detected, and numerical simulations reveal that the system undergoes degenerate Hopf bifurcation. When the system is periodically forced, bifurcation diagrams for periodic solutions of period-one and period-two are given by researching the Poincaré map, corresponding to different bifurcation cases in the unforced system. Stable and unstable quasiperiodic solutions are obtained by Neimark-Sacker bifurcation with different parameter values. Periodic solutions of various periods can occur or disappear and even change their stability, when the Poincaré map of the forced system undergoes Neimark-Sacker bifurcation, flip bifurcation, and fold bifurcation. Chaotic attractors generated by a cascade of period doublings and some phase portraits are given at last.

  19. Growth performance of African catfish Clarias gariepinus cultured in biofloc system at high stocking density

    Directory of Open Access Journals (Sweden)

    Petrus Hary Tjahja Soedibya

    2017-07-01

    Full Text Available ABSTRACT This study was aimed to analyze the growth performance of African catfish Clarias gariepinus cultured in the biofloc system at high stocking density. African catfish with an average weight of 1.85±0.09 g were cultured in four units of tarpaulin tank at a diameter of 1.72 m and a height of 1.05 m with a volume of ±2,000 L at the different density of 1,000 fish/m3; 1,500 fish/m3; 2,000 fish/m3; 2,500 fish/m3. During rearing period, fish were given the artificial feed with protein contents of 28.75% with the frequency of twice a day, as much as 3% of the body weight. The results showed that different treatment of high stocking density in the biofloc system had a significant effect on the absolute growth rate, lipid retention and energy retention (P<0.05 but not significant effect on daily growth rate. The results showed that the highest lipid retention and energy retention were found in the group of fish treated at a stocking density of 2,500 fish/m3 but declining protein retention and growth in fish occurred. The highest absolute growth rate and daily growth rate were shown by treatment with a stocking density of 1,500 fish/m3. Keywords: growth, stocking density, biofloc   ABSTRAK Penelitian ini bertujuan untuk menganalisis performa pertumbuhan ikan lele dumbo Clarias gariepinus yang dipelihara pada sistem bioflok dengan padat penebaran tinggi.  Ikan uji memiliki berat rata-rata 1,85±0,09 g yang dipelihara pada kolam terpolin berdiameter 1,72 m dan tinggi 1,05 m dengan volume air ±2.000 L sebanyak empat unit dengan kepadatan yang berbeda yaitu 1.000 ekor/m3, 1.500 ekor/m3, 2.000 ekor/m3, 2.500 ekor/m3. Selama 40 hari masa pemeliharaan, ikan diberi pakan buatan berkadar protein 28,75% dengan frekwensi dua kali sehari, sebanyak 3% dari berat tubuh. Hasil penelitian menunjukkan bahwa perlakuan perbedaan padat penebaran tinggi pada sistem bioflok memberikan pengaruh yang nyata terhadap pertumbuhan mutlak, retensi lemak dan retensi

  20. PROOF on a Batch System

    International Nuclear Information System (INIS)

    Behrenhoff, W; Ehrenfeld, W; Samson, J; Stadie, H

    2011-01-01

    The 'parallel ROOT facility' (PROOF) from the ROOT framework provides a mechanism to distribute the load of interactive and non-interactive ROOT sessions on a set of worker nodes optimising the overall execution time. While PROOF is designed to work on a dedicated PROOF cluster, the benefits of PROOF can also be used on top of another batch scheduling system with the help of temporary per user PROOF clusters. We will present a lightweight tool which starts a temporary PROOF cluster on a SGE based batch cluster or, via a plugin mechanism, e.g. on a set of bare desktops via ssh. Further, we will present the result of benchmarks which compare the data throughput for different data storage back ends available at the German National Analysis Facility (NAF) at DESY.

  1. Optimization of an effective growth medium for culturing probiotic bacteria for applications in strict vegetarian food products

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    Manju Pathak

    2012-10-01

    Full Text Available Background: This study aimed to modify de Man Rogosa Sharpe culture medium (termed MRS for selective cultivation of probiotics strain for the consumption by the strictly vegetarian human population. Vegetarian probiotic foods by definition must be free from all animal-derived ingredients. This not only includes the product ingredients but the probiotic inoculum as well. Probiotic starter cultures are traditionally grown and stored in media containing milk or meatderived ingredients. The presence of these ingredients makes the probiotic cell concentrates unsuitable for use in vegetarian products and thus creates the need for a growth medium which isfree from animal-derived ingredients. Present study investigated the growth of a strain of Lactobacillus lactis in MRS. The present invention relates in general to a bacterial culture media,and more specifically a complex microbial culture media, based on plant seed powder extract in place of animal extract for probiotic bacterial growth.Methods: Lactobacillus lactis, a probiotic, was grown in standard MRS culture medium as well as in our various test media (TM containing various vegetal source in place of beef extract, yeast extract and peptone as in case of MRS. The inoculated culture mediums were incubated at 37C for 72 hours and growth of probiotic is recorded at regular intervals. The growth was recorded as Colony Forming Units (CFUs.Results: The best growth of probiotic is observed in TM 2. TM 2 is the leguminous seed extract. Starter culture mediums for probiotics or other bacteria primarily contain protein from animal source. The possibility of using vegetal protein from TM 2 extract in place of peptones and meat extract for the nitrogen supplementation of culture media for the growth of lactic acid bacteria has been demonstrated.Functional Foods in Health and Disease 2012, 2(10:369-378 Conclusion: The absolute vegetarian culture medium containing TM 2 is better than standard MRS for the

  2. An Axenic Plant Culture System for Optimal Growth in Long-Term Studies: Design and Maintenance

    Science.gov (United States)

    Henry, Amelia; Doucette, William; Norton, Jeanette; Jones, Scott; Chard, Julie; Bugbee, Bruce

    2006-01-01

    The symbiotic co-evolution of plants and microbes leads to difficulties in understanding which of the two components is responsible for a given environmental response. Plant-microbe studies greatly benefit from the ability to grow plants in axenic (sterile) culture. Several studies have used axenic plant culture systems, but experimental procedures are often poorly documented, the plant growth environment is not optimal, and axenic conditions are not rigorously verified. We developed a unique axenic system using inert components that promotes plant health and can be kept sterile for at least 70 d. Crested wheatgrass (Agropyron cristatum cv. DII) plants were grown in sand within flow-through glass columns that were positively pressured with filtered air. Plant health was optimized by regulating temperature, light level, CO2 concentration, humidity, and nutrients. The design incorporates several novel aspects, such as pretreatment of the sand with Fe, graduated sand layers to optimize the air-water balance of the root zone, and modification of a laminar flow hood to serve as a plant growth chamber. Adaptations of several sterile techniques were necessary for maintenance of axenic conditions. Axenic conditions were verified by plating and staining leachates as well as rhizoplane stain. This system was designed to study nutrient and water stress effects on root exudates, but is useful for assessing a broad range of plant-microbe-environment interactions. Based on total organic C analysis, 74% of exudates was recovered in the leachate, 6% was recovered in the bulk sand, and 17% was recovered in the rhizosphere sand. Carbon in the leachate after 70 d reached 255 micro-g/d. Fumaric, malic, malonic, oxalic, and succinic acids were measured as components of the root exudates.

  3. Relations between pH, oxygen partial pressure and growth in cultured cell spheroids.

    Science.gov (United States)

    Carlsson, J; Acker, H

    1988-11-15

    The pH gradients, oxygen partial-pressure gradients and growth curves were measured for 7 different types of spheroids. Growth curves were measured in liquid overlay culture and thereafter the spheroids were attached to cover glasses and transferred to a chamber for micro-electrode measurements. The spheroids were randomly divided for pH or pO2 measurements which then were made under conditions as identical as possible. The decreases in pO2 and pH, delta pO2 and delta pH were calculated as the difference between the values in the culture medium and the values 200 micron inside the spheroids. Each type of spheroid had a certain relation between delta pO2 and delta pH. The human colon carcinoma HT29, the mouse mammary carcinoma EMT6 and the hamster lung V79-379A spheroids had high values of the quotient delta pO2/delta pH. The human thyroid carcinoma HTh7 spheroids and the 3 types of human glioma spheroids had lower quotients. There was a tendency for fast-growing spheroids to have high quotients. Two extreme types of spheroids, HT29 (high quotient) and U-118 MG (low quotient) were analyzed for lactate production and oxygen consumption. The U-118 MG spheroids produced about 3 times more lactate and consumed about 3 times less oxygen than the HT29 spheroids. The differences in lactate production could not be explained by differences in the pyruvate Km values of lactate dehydrogenase. The results indicate that there are significant metabolic differences between the spheroid systems studied.

  4. Low Doses of Celecoxib Stimulate Human Endometrium Growth in A Three-Dimensional Culture Model

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    Mohammad Rasool Khazaei

    2013-01-01

    Full Text Available Background: The endometrium plays a pivotal role in implantation and pregnancy. CyclooxygenaseII (COX-2 has an important function in biological processes such as cellproliferation and inflammation. Celecoxib is a selective inhibitor of COX-2 with numerouspharmacologic functions. The aim of present study is to investigate the effects ofcelecoxib on the human endometrium in a three-dimensional (3D culture model.Materials and Methods: In this experimental study, normal human endometria (n=10obtained from reproductive age women were cut into 1×1 mm sections. Endometrialexplants were placed between two layers of fibrin gel. To create the fibrin gel, we poureda thin layer of fibrinogen solution [3 mg/ml in medium 199 (M199] into each well of a24-well culture dish and added thrombin enzyme. Endometrial fragments were placed inthe center of each well and covered with a second layer of fibrinogen solution. M199 supplementedwith L-glutamine, fetal bovine serum (FBS, 5% and antibiotics were addedto each well. The media in each experimental well contained either1, 10 or 50 μM ofcelecoxib. At the end of the study, we calculated endometrial tissue growth changes byscoring methods and determined the percentage of angiogenesis. Data were analyzed bythe Kruskal-Wallis method. P<0.05 was considered significant.Results: The growth scores were as follows: control (1.37 ± 0.16, 1 μM (1.96 ± 0.28,10 μM (2.01 ± 0.25, and 50 μM (1.17 ± 0.14 celecoxib, all of which were significantlydifferent. The angiogenesis percentages were: 25.56 ± 6.72% (control, 31.98 ± 6.18% (1μM, 42.67 ± 7.27% (10 μM and 23.44 ± 4.03% (50 μM, which were not significantlydifferent from each other.

  5. IVF culture medium affects human intrauterine growth as early as the second trimester of pregnancy.

    Science.gov (United States)

    Nelissen, Ewka C M; Van Montfoort, Aafke P A; Smits, Luc J M; Menheere, Paul P C A; Evers, Johannes L H; Coonen, Edith; Derhaag, Josien G; Peeters, Louis L; Coumans, Audrey B; Dumoulin, John C M

    2013-08-01

    When does a difference in human intrauterine growth of singletons conceived after IVF and embryo culture in two different culture media appear? Differences in fetal development after culture of embryos in one of two IVF media were apparent as early as the second trimester of pregnancy. Abnormal fetal growth patterns are a major risk factor for the development of chronic diseases in adult life. Previously, we have shown that the medium used for culturing embryos during the first few days after fertilization significantly affects the birthweight of the resulting human singletons. The exact onset of this growth difference was unknown. In this retrospective cohort study, all 294 singleton live births after fresh embryo transfer in the period July 2003 to December 2006 were included. These embryos originated from IVF treatments that were part of a previously described clinical trial. Embryos were allocated to culture in either Vitrolife or Cook commercially available sequential culture media. We analysed ultrasound examinations at 8 (n = 290), 12 (n = 83) and 20 weeks' (n = 206) gestation and used first-trimester serum markers [pregnancy-associated plasma protein-A (PAPP-A) and free β-hCG]. Differences between study groups were tested by the Student's t-test, χ(2) test or Fisher's exact test, and linear multivariable regression analysis to adjust for possible confounders (for example, parity, gestational age at the time of ultrasound and fetal gender). A total of 294 singleton pregnancies (Vitrolife group nVL = 168, Cook group: nC = 126) from 294 couples were included. At 8 weeks' gestation, there was no difference between crown-rump length-based and ovum retrieval-based gestational age (ΔGA) (nVL = 163, nC = 122, adjusted mean difference, -0.04 days, P = 0.84). A total of 83 women underwent first-trimester screening at 12 weeks' gestation (nVL = 45, nC = 38). ΔGA, nuchal translucency (multiples of median, MoM) and PAPP-A (MoM) did not differ between the study

  6. Streetcar Desires: The Death of the Arlington Streetcar and the Cultural Politics of Smart Growth Development

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    Timothy A. Gibson

    2017-09-01

    Full Text Available In 2014, Arlington County—an affluent suburb of Washington, DC—became embroiled in a bitter political debate over a proposed streetcar line on Columbia Pike, a street that traverses some of the County’s last remaining working-class and new immigrant neighborhoods. Viewed alternatively as vanguard for gentrification, a symbol of sustainable development, and a big government boondoggle, the proposed streetcar brought to the surface ideological and class antagonisms which are typically muted in Arlington’s broadly liberal-progressive political culture. Drawing on comments posted on a local news blog as well as interviews with advocates, this paper examines the streetcar debate through the lens of Stuart Hall’s theory of articulation and Janice Radway’s metaphor of “ideological seams.” In particular, the paper explores how streetcar opponents wove together an unlikely rhetorical fabric, intertwining fears of gentrification, a critique of “big government,” and a rearguard defense of suburban automobility. A concluding section discusses what the death of the Arlington Streetcar can reveal about the cultural politics of smart growth development and sustainable urban planning.

  7. EFFECT OF PHYSIOLOGICAL AGE AND GROWTH REGULATORS ON CALLUS BROWNING OF COCONUT ENDOSPERM CULTURE IN VITRO

    Directory of Open Access Journals (Sweden)

    LAZARUS AGUS SUKAMTO

    2011-01-01

    Full Text Available The possibility of physiological age and growth regulators affecting callus browning ofcoconut endosperm was investigated. Solid endosperm explants of four coconut fruits fromsame brunches of two coconut cultivars “Samoan Dwarf ” were grown on modified Murashigeand Skoog (MS formula with addition of 10 mg l putresine, 2.50 g l activated charcoal (AC,1.70 g l phytagel, 0, 10 , 10 , 10 , 10 M 2,4-dichlorophenoxyacetic acid (2,4-D or 4-amino-3,5,6-trichloropicolinic acid (Picloram combined with 10 M 6-benzylaminopurine (BA.Callogenesis occurred on 98.83% of explants. Callus browning between different physiologicalages (antipodal and micropylar tissues of coconut endosperm at 9, 26 and 31 weeks of culture(WOC was significantly different, but not at 16 and 21 WOC. Auxins of 2,4-D and Picloramdid not affect significantly callus browning of endosperm cultures. Auxin doses at 10 , 10 , and10 M decreased significantly callus browning at 9 and 16 WOC, respectively, but at 10 Mbrowning was less significant compared to other doses at 21 WOC. Auxin dose at 10 M causedless significant browning compared to other doses at 31 WOC. The addition of BA decreasedsignificantly callus browning at 9 WOC, but did not affect callus browning thereafter.

  8. The cultural divide: exponential growth in classical 2D and metabolic equilibrium in 3D environments.

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    Krzysztof Wrzesinski

    Full Text Available INTRODUCTION: Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures and the other by a dynamic equilibrium (in 3D cultures. We have analyzed the proteome and cellular architecture at these two extremes and found that they are dramatically different. RESULTS: Structurally, actin organization is changed, microtubules are increased and keratins 8 and 18 decreased. Metabolically, glycolysis, fatty acid metabolism and the pentose phosphate shunt are increased while TCA cycle and oxidative phosphorylation is unchanged. Enzymes involved in cholesterol and urea synthesis are increased consistent with the attainment of cholesterol and urea production rates seen in vivo. DNA repair enzymes are increased even though cells are predominantly in Go. Transport around the cell--along the microtubules, through the nuclear pore and in various types of vesicles has been prioritized. There are numerous coherent changes in transcription, splicing, translation, protein folding and degradation. The amount of individual proteins within complexes is shown to be highly coordinated. Typically subunits which initiate a particular function are present in increased amounts compared to other subunits of the same complex. SUMMARY: We have previously demonstrated that cells at dynamic equilibrium can match the physiological performance of cells in tissues in vivo. Here we describe the multitude of protein changes necessary to achieve this performance.

  9. The cultural divide: exponential growth in classical 2D and metabolic equilibrium in 3D environments.

    Science.gov (United States)

    Wrzesinski, Krzysztof; Rogowska-Wrzesinska, Adelina; Kanlaya, Rattiyaporn; Borkowski, Kamil; Schwämmle, Veit; Dai, Jie; Joensen, Kira Eyd; Wojdyla, Katarzyna; Carvalho, Vasco Botelho; Fey, Stephen J

    2014-01-01

    Cellular metabolism can be considered to have two extremes: one is characterized by exponential growth (in 2D cultures) and the other by a dynamic equilibrium (in 3D cultures). We have analyzed the proteome and cellular architecture at these two extremes and found that they are dramatically different. Structurally, actin organization is changed, microtubules are increased and keratins 8 and 18 decreased. Metabolically, glycolysis, fatty acid metabolism and the pentose phosphate shunt are increased while TCA cycle and oxidative phosphorylation is unchanged. Enzymes involved in cholesterol and urea synthesis are increased consistent with the attainment of cholesterol and urea production rates seen in vivo. DNA repair enzymes are increased even though cells are predominantly in Go. Transport around the cell--along the microtubules, through the nuclear pore and in various types of vesicles has been prioritized. There are numerous coherent changes in transcription, splicing, translation, protein folding and degradation. The amount of individual proteins within complexes is shown to be highly coordinated. Typically subunits which initiate a particular function are present in increased amounts compared to other subunits of the same complex. We have previously demonstrated that cells at dynamic equilibrium can match the physiological performance of cells in tissues in vivo. Here we describe the multitude of protein changes necessary to achieve this performance.

  10. Response of growth, quality parameters and photosynthetic apparatus of endive plant to different culture media

    Directory of Open Access Journals (Sweden)

    Kowalczyk Katarzyna

    2016-06-01

    Full Text Available Endive (Cichorium endivia L. is a leaf vegetable with high vitamin and nutritional values. Therefore, an increase of its cultivation in Poland and other European countries has been observed in recent years. The aim of this research was to study the effect of different growth media on the quality and photosynthetic efficiency of different endive cultivars. The experiment was conducted in controlled greenhouse conditions. Endive was grown in three independent NFT cultivation systems: a standard culture medium (control, A1, a culture medium concentrated three-fold (A2 and a medium concentrated five-fold (A3. Four cultivars were used: ‘Kethel’, ‘Barundi’, ‘Galanti’ and ‘Perceval’. The plants were examined for the number and weight of fully-grown leaves and the weight of roots, dry matter content and chemical quality attributes of endive such as ascorbic acid (AA, total soluble solids (TSS, chlorophyll and proline. In addition, several physiological traits such as modulated chlorophyll a fluorescence were measured.

  11. Versatile modeling and optimization of fed batch processes for the production of secreted heterologous proteins with Pichia pastoris

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    Gasser Brigitte

    2006-12-01

    Full Text Available Abstract Background Secretion of heterologous proteins depends both on biomass concentration and on the specific product secretion rate, which in turn is not constant at varying specific growth rates. As fed batch processes usually do not maintain a steady state throughout the feed phase, it is not trivial to model and optimize such a process by mathematical means. Results We have developed a model for product accumulation in fed batch based on iterative calculation in Microsoft Excel spreadsheets, and used the Solver software to optimize the time course of the media feed in order to maximize the volumetric productivity. The optimum feed phase consisted of an exponential feed at maximum specific growth rate, followed by a phase with linearly increasing feed rate and consequently steadily decreasing specific growth rate. The latter phase could be modeled also by exact mathematical treatment by the calculus of variations, yielding the explicit shape of the growth function, however, with certain indeterminate parameters. To evaluate the latter, one needs a numerical optimum search algorithm. The explicit shape of the growth function provides additional evidence that the Excel model results in correct data. Experimental evaluation in two independent fed batch cultures resulted in a good correlation to the optimized model data, and a 2.2 fold improvement of the volumetric productivity. Conclusion The advantages of the procedure we describe here are the ease of use and the flexibility, applying software familiar to every scientist and engineer, and rapid calculation which makes predictions extremely easy, so that many options can be tested in silico quickly. Additional options like further biological and technological constraints or different functions for specific productivity and biomass yield can easily be integrated.

  12. Versatile modeling and optimization of fed batch processes for the production of secreted heterologous proteins with Pichia pastoris.

    Science.gov (United States)

    Maurer, Michael; Kühleitner, Manfred; Gasser, Brigitte; Mattanovich, Diethard

    2006-12-11

    Secretion of heterologous proteins depends both on biomass concentration and on the specific product secretion rate, which in turn is not constant at varying specific growth rates. As fed batch processes usually do not maintain a steady state throughout the feed phase, it is not trivial to model and optimize such a process by mathematical means. We have developed a model for product accumulation in fed batch based on iterative calculation in Microsoft Excel spreadsheets, and used the Solver software to optimize the time course of the media feed in order to maximize the volumetric productivity. The optimum feed phase consisted of an exponential feed at maximum specific growth rate, followed by a phase with linearly increasing feed rate and consequently steadily decreasing specific growth rate. The latter phase could be modeled also by exact mathematical treatment by the calculus of variations, yielding the explicit shape of the growth function, however, with certain indeterminate parameters. To evaluate the latter, one needs a numerical optimum search algorithm. The explicit shape of the growth function provides additional evidence that the Excel model results in correct data. Experimental evaluation in two independent fed batch cultures resulted in a good correlation to the optimized model data, and a 2.2 fold improvement of the volumetric productivity. The advantages of the procedure we describe here are the ease of use and the flexibility, applying software familiar to every scientist and engineer, and rapid calculation which makes predictions extremely easy, so that many options can be tested in silico quickly. Additional options like further biological and technological constraints or different functions for specific productivity and biomass yield can easily be integrated.

  13. Cell engineering of Escherichia coli allows high cell density accumulation without fed-batch process control.

    Science.gov (United States)

    Bäcklund, Emma; Markland, Katrin; Larsson, Gen

    2008-01-01

    A set of mutations in the phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) was used to create Escherichia coli strains with a reduced uptake rate of glucose. This allows a growth restriction, which is controlled on cellular rather than reactor level, which is typical of the fed-batch cultivation concept. Batch growth of the engineered strains resulted in cell accumulation profiles corresponding to a growth rate of 0.78, 0.38 and 0.25 h(-1), respectively. The performance of the mutants in batch cultivation was compared to fed-batch cultivation of the wild type cell using restricted glucose feed to arrive at the corresponding growth profiles. Results show that the acetate production, oxygen consumption and product formation were similar, when a recombinant product was induced from the lacUV5 promoter. Ten times more cells could be produced in batch cultivation using the mutants without the growth detrimental production of acetic acid. This allows high cell density production without the establishment of elaborate fed-batch control equipment. The technique is suggested as a versatile tool in high throughput multiparallel protein production but also for increasing the number of experiments performed during process development while keeping conditions similar to the large-scale fed-batch performance.

  14. Metabolomics profiling of cell culture media leading to the identification of riboflavin photosensitized degradation of tryptophan causing slow growth in cell culture.

    Science.gov (United States)

    Zang, Li; Frenkel, Ruth; Simeone, Jeffrey; Lanan, Maureen; Byers, Mark; Lyubarskaya, Yelena

    2011-07-01

    As more protein biopharmaceuticals are produced using mammalian cell culture techniques, it becomes increasingly important for the biopharmaceutical industry to have tools to characterize the cell culture media and evaluate its impact on the cell culture performance. Exposure of the cell culture media to light, temperature stress, or adventitious introduction of low-level organisms during preparation can lead to the generation of chemical degradants or metabolites of the media components, which are potentially detrimental to the cell culture process. In this work, we applied a liquid chromatography-mass spectrometry based metabolomics methodology for the investigation of a media lot used for a mammalian cell culture process that had resulted in low growth rate and failure to meet required viable cell density (VCD). The study led to the observation of increased levels of tryptophan oxidation products and a riboflavin degradant, lumichrome, in the malfunctioning media lot, relative to working media lots. A compound found 7-fold higher in the working media lots appeared to be tetrahydropentoxyline, a condensation product of glucose and tryptophan. A second compound found at an over 50-fold higher level in the malfunctioning media lot with a proposed molecular formula of C(21)H(17)N(3)O(3) from high-resolution mass spectrometry (HRMS) analysis remains unknown, although it is confirmed to be a degradant of tryptophan in the media. A study of the cell culture media performed under stress conditions using fluorescent light and heat showed that the media powder was highly resistant to light-induced degradation, while solution media could be easily degraded after brief light exposure. It is therefore suspected that inadvertent exposure of the media to light during preparation and storage has resulted in the poor performance of the media causing the low growth and VCD in the cell culture process.

  15. Effect of growth regulators in meristem culture of potato (solanum tuberosmum l.)

    International Nuclear Information System (INIS)

    Batool, A.; Zaidi, S.S.H.

    2014-01-01

    Two growth regulators, viz., Gibberellic acid (GA3) and Naphthalene acetic acid (NAA) and a combination of both (GA3 and NAA) were evaluated at three different levels (200, 300 and 400 meul) to check the growth rate of root, shoot, number of leaves and nodes of potato plantlets in two potato varieties, namely cardinal and SH-5, grown by meristem culture. Analysis of variance revealed highly significant differences between varieties, hormones and their interaction for all the studied traits. Mean values revealed that among two varieties Cardinal produced root length (0.70 cm), shoot length (2.50 cm), number of leaves (6.96) and number of nodes (8) are better than the SH-5 which produced root length (0.54 cm), shoot length (1.38 cm), number of leaves (4.29) and number of nodes (5.3). The variety cardinal and GA3 at 300 meul followed by 200 meul produced most suitable results. By using the concentration of 300 meul maximum root length of (1.40 cm), shoot length of (3.43 cm), number of leaves (10) and no of nodes (11) was obtained. At 200 meul, though root and shoot length obtained was very similar at 300 meul but produced less number of leaves and nodes. (author)

  16. Effects of coronatine elicitation on growth and metabolic profiles of Lemna paucicostata culture.

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    Jin-Young Kim

    Full Text Available In this study, the effects of coronatine treatment on the growth, comprehensive metabolic profiles, and productivity of bioactive compounds, including phenolics and phytosterols, in whole plant cultures of Lemna paucicostata were investigated using gas chromatography-mass spectrometry (GC-MS coupled with multivariate statistical analysis. To determine the optimal timing of coronatine elicitation, coronatine was added on days 0, 23, and 28 after inoculation. The total growth of L. paucicostata was not significantly different between the coronatine treated groups and the control. The coronatine treatment in L. paucicostata induced increases in the content of hydroxycinnamic acids, such as caffeic acid, isoferulic acid, ρ-coumaric acid, sinapic acid, and phytosterols, such as campesterol and β-sitosterol. The productivity of these useful metabolites was highest when coronatine was added on day 0 and harvested on day 32. These results suggest that coronatine treatment on day 0 activates the phenolic and phytosterol biosynthetic pathways in L. paucicostata to a greater extent than in the control. To the best of our knowledge, this is the first report to investigate the effects of coronatine on the alteration of metabolism in L. paucicostata based on GC-MS profiling. The results of this research provide a foundation for designing strategies for enhanced production of useful metabolites for pharmaceutical and nutraceutical industries by cultivation of L. paucicostata.

  17. Winter Growth of Carps under Different Semi-Intensive Culture Conditions

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    Nadia Nazish* and Abdul Mateen

    2011-04-01

    Full Text Available The experiment was planned to observe the influence of different semi intensive culture conditions i.e. organic and inorganic fertilizer with rice polish on the growth of carps during winter season. Two earthen ponds were selected and each pond was stocked with Silver carp (Hypophthalmichthys molitrix, Rohu (Labeo rohita and Mori (Cirrhinus mrigala at the ratio of 1:2:1 respectively with a total number of 44 fishes. Pond 1 was treated with poultry dropping and urea while pond 2 was treated with poultry dropping, urea and rice polish. The ponds were treated with at the rate of 0.2 g N/100g of wet body weight of fish. Fertilizers were added on weekly basis while rice polish was added daily. Total net fish production of pond 1 and pond 2 was remained 797.3 and 1033.0 kg/ha/year. The pond treated with fertilizer and artificial feed (rice polish showed 3.6% more fish production than the pond treated only with fertilizer. The physico-chemical parameters were measured on weekly basis. Temperature, light penetration, pH and planktonic biomass showed non-significant difference in both ponds. Pond 2 which was treated with poultry dropping, urea and rice polish showed 1.26 times greater fish growth than pond 1 which was treated with poultry dropping and urea.

  18. Inhibition of the Growth of Plasmodium falciparum in Culture by Stearylamine-Phosphatidylcholine Liposomes

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    Gulam Mustafa Hasan

    2011-01-01

    Full Text Available We have examined the effect of stearylamine (SA in liposomes on the viability of Plasmodium falciparum in culture by studying the inhibition of incorporation of [3H]-hypoxanthine in the nucleic acid of parasites. Stearylamine in liposomes significantly inhibits the growth of the parasites depending on the phospholipids composition. The maximum inhibition was observed when SA was delivered through Soya phosphatidylcholine (SPC liposomes. The chain length of alkyl group and density of SA in liposomes play a significant role in inhibiting the growth of the parasites. Incorporation of either cholesterol or Distearylphosphatidylethanolamine−Methoxy-Polyethylene glycol-2000 (DSPE-mPEG-2000 in Soya phosphatidylcholine-stearylamine (SPC-SA liposomes improves the efficacy. Intraerythrocytic entry of intact SPC-SA liposomes into infected erythrocytes was visualized using fluorescent microscopy. No hemolysis was observed in uninfected erythrocytes, and slight hemolysis was noted in infected erythrocytes at high concentrations of SPC-SA liposomes. Overall, our data suggested SA in SPC-liposomes might have potential application in malaria chemotherapy.

  19. Outdoor Growth Characterization of an Unknown Microalga Screened from Contaminated Chlorella Culture

    Science.gov (United States)

    Zhou, Weizheng; Zhu, Feifei

    2017-01-01

    Outdoor microalgae cultivation process is threatened by many issues, such as pest pollution and complex, changeable weather. Therefore, it is difficult to have identical growth rate for the microalgae cells and to keep their continuous growth. Outdoor cultivation requires the algae strains not only to have a strong ability to accumulate oil, but also to adapt to the complicated external environment. Using 18S rRNA technology, one wild strain Scenedesmus sp. FS was isolated and identified from the culture of Chlorella zofingiensis. Upon contamination by Scenedesmus sp., the species could quickly replace Chlorella zofingiensis G1 and occupy ecological niche in the outdoor column photobioreactors. The results indicated that Scenedesmus sp. FS showed high alkali resistance. It also showed that even under the condition of a low inoculum rate (OD680, 0.08), Scenedesmus sp. FS could still grow in the outdoor raceway pond under a high alkaline environment. Even under unoptimized conditions, the oil content of Scenedesmus sp. FS could reach more than 22% and C16–C18 content could reach up to 79.68%, showing that this species has the potential for the biodiesel production in the near future. PMID:28357405

  20. Outdoor Growth Characterization of an Unknown Microalga Screened from Contaminated Chlorella Culture

    Directory of Open Access Journals (Sweden)

    Shuhao Huo

    2017-01-01

    Full Text Available Outdoor microalgae cultivation process is threatened by many issues, such as pest pollution and complex, changeable weather. Therefore, it is difficult to have identical growth rate for the microalgae cells and to keep their continuous growth. Outdoor cultivation requires the algae strains not only to have a strong ability to accumulate oil, but also to adapt to the complicated external environment. Using 18S rRNA technology, one wild strain Scenedesmus sp. FS was isolated and identified from the culture of Chlorella zofingiensis. Upon contamination by Scenedesmus sp., the species could quickly replace Chlorella zofingiensis G1 and occupy ecological niche in the outdoor column photobioreactors. The results indicated that Scenedesmus sp. FS showed high alkali resistance. It also showed that even under the condition of a low inoculum rate (OD680, 0.08, Scenedesmus sp. FS could still grow in the outdoor raceway pond under a high alkaline environment. Even under unoptimized conditions, the oil content of Scenedesmus sp. FS could reach more than 22% and C16–C18 content could reach up to 79.68%, showing that this species has the potential for the biodiesel production in the near future.

  1. Batch Cultivation Model for Biopolymer Production

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    C. E. Torres-Cerna

    2017-04-01

    Full Text Available This paper presents a mathematical model to evaluate the kinetics of two different Pseudomonas putida strains, wild and mutant-type for the microbial production of polyhydroxyalkanoates (PHAs. Model parameters were estimated to represent adequately experimental data from the batch reactor using the differential evolution algorithm. Based on the mathematical model with the best-fit parameter values, simulations suggested that the high production of PHA by the mutant strain can be attributed not only to the higher production of PHA but also to a reduction in the consumption rate of the substrates of approximately 66 %. Remarkably, the cell growth rate value is higher for the wild type than the mutant type, suggesting that the PHA increase is not only to an increase in the production rate but also to the metabolism of the cells. This mathematical model advances comprehension of the PHA production capacity by P. putida paving the road towards environmentally friendly plastics.

  2. Effects of Plant Growth Regulators on Shoot Multiplication and Root Induction of Cassava Varieties Culture in Vitro

    OpenAIRE

    SUKMADJAJA, DEDEN; WIDHIASTUTI, HERNI

    2011-01-01

    A study on propagation of three superior cassava Manihot esculenta( Crant) varieties i.e.Darul Hidayah, Malang-6 and Adira-4 through tissue culture technique was conducted at theTissue Culture Lab of SEAMEO BIOTROP, Bogor. The objective of the experiment was tostudy effect of plant growth regulators on Manihot esculenta propagation, which can be used in cassavamicropropagation protocol. Plant materials used were auxiliary shoots of a stem node. Theexperiment consisted of (i) shoot multiplicat...

  3. Changes in auxin level in the course of growth of a sunflower crown-gall suspension culture

    Directory of Open Access Journals (Sweden)

    Zofia Chirek

    2014-01-01

    Full Text Available The auxin level in the cell mass and culture medium was determined by means of the Avena straight caleoptile test in various periods of the suspension culture cycle of the sunflower crown-gall tumour. The investigations were performed in the course of the zero passage (PO and first one (Pl, differing in their time of duration of maximum growth and its intensity. In both passages the intra- and extra-cellular auxin levels reach values of the same order. At the beginning of the maximal growth phase the activity corresponding to IAA in the cells prevails over that of the other auxin-like compounds. This disproportion diminishes with further development of the culture, and with the beginning of the stationary phase the cellular IAA level is lower than that of the remaining auxin-like compounds. The short phase of maximal growth (PO occurs with an auxin level decreasing in the cell mass and increasing in the medium, and towards the end of the cycle these levels become equal. During the long phase of maximal growth (Pl the total amount of auxins in the cells increases and is 2-3 times higher than in the medium, whereas IAA in the cells remains at a constant level. These results suggest that the participation of IAA in the intracellular pool of auxin-like substances is decisive for the mitotic activity of the cells and maintenance of growth in the culture.

  4. Trickle water and feeding system in plant culture and light-dark cycle effects on plant growth

    Science.gov (United States)

    Takano, T.; Inada, K.; Takanashi, J.

    Rockwool, as an inert medium covered or bagged with polyethylene film, can be effectively used for plant culture in space station. The most important machine is the pump adjusting the dripping rate in the feeding system. Hydro-aeroponics may be adaptable to a space laboratory. The shortening of the light-dark cycles inhibits plant growth and induces an abnormal morphogenesis. A photoperiod of 12-hr-dark may be needed for plant growth.

  5. Growth characteristics and nutrient depletion of Miscanthus x ogiformis Honda 'Giganteus' suspension cultures

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted

    1998-01-01

    The growth characteristics and nutrient depletion in suspension cultures of Miscanthus ogiformis Honda ‘Giganteus' grown in media containing either Murashige and Skoog or N6 basal nutrient salts were studied during a culture period of 15 days. Proline was added to both media in concentrations from...... 0 to 300 mM. The fresh and dry weights of the suspension aggregates and the concentrations of ammonium, nitrate, proline and sugar remaining in the medium were measured at different points in time during the culture period. The results showed an almost total depletion of ammonium but a limited...

  6. Mixed-culture transcriptome analysis reveals the molecular basis of mixed-culture growth in Streptococcus thermophilus and Lactobacillus bulgaricus

    NARCIS (Netherlands)

    Sieuwerts, S.; Molenaar, D.; Hijum, van S.A.F.T.; Beerthuyzen, M.; Stevens, M.J.A.; Janssen, P.W.; Ingham, C.J.; Bok, de F.A.M.; Vos, de W.M.; Hylckama Vlieg, van J.E.T.

    2010-01-01

    Many food fermentations are performed using mixed cultures of lactic acid bacteria. Interactions between strains are of key importance for the performance of these fermentations. Yogurt fermentation by Streptococcus thermophilus and Lactobacillus bulgaricus (basonym, Lactobacillus delbrueckii subsp.

  7. 6-Gingerol Inhibits Hair Shaft Growth in Cultured Human Hair Follicles and Modulates Hair Growth in Mice

    OpenAIRE

    Miao, Yong; Sun, Yabin; Wang, Wenjun; Du, Benjun; Xiao, Shun-e; Hu, Yijue; Hu, Zhiqi

    2013-01-01

    Ginger (Zingiber officinale) has been traditionally used to check hair loss and stimulate hair growth in East Asia. Several companies produce shampoo containing an extract of ginger claimed to have anti-hair loss and hair growth promotion properties. However, there is no scientific evidence to back up these claims. This study was undertaken to measure 6-gingerol, the main active component of ginger, on hair shaft elongation in vitro and hair growth in vivo, and to investigate its effect on hu...

  8. Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base CELSS (Controlled Ecological Life Support System)

    Science.gov (United States)

    Venketeswaran, S.

    1988-01-01

    Experiments were carried out on plant tissue cultures, seed germination, seedling development and plants grown on Simulated Lunar Soil to evaluate the potential of future development of lunar based agriculture. The studies done to determine the effect of the placement of SLS on tissue cultures showed no adverse effect of SLS on tissue cultures. Although statistically insignificant, SLS in suspension showed a comparatively higher growth rate. Observations indicate the SLS, itself cannot support calli growth but was able to show a positive effect on growth rate of calli when supplemented with MS salts. This positive effect related to nutritive value of the SLS was found to have improved at high pH levels, than at the recommended low pH levels for standard media. Results from seed germination indicated that there is neither inhibitory, toxicity nor stimulatory effect of SLS, even though SLS contains high amounts of aluminum compounds compared to earth soil. Analysis of seeding development and growth data showed significant reduction in growth rate indicating that, SLS was a poor growth medium for plant life. This was confirmed by the studies done with embryos and direct plant growth on SLS. Further observations attributed this poor quality of SLS is due to it's lack of essential mineral elements needed for plant growth. By changing the pH of the soil, to more basic conditions, the quality of SLS for plant growth could be improved up to a significant level. Also it was found that the quality of SLS could be improved by almost twice, by external supply of major mineral elements, directly to SLS.

  9. Effect of nitrogen-rich cell culture surfaces on type X collagen expression by bovine growth plate chondrocytes

    Directory of Open Access Journals (Sweden)

    Wertheimer Michael R

    2011-01-01

    Full Text Available Abstract Background Recent evidence indicates that osteoarthritis (OA may be a systemic disease since mesenchymal stem cells (MSCs from OA patients express type X collagen, a marker of late stage chondrocyte hypertrophy (associated with endochondral ossification. We recently showed that the expression of type X collagen was suppressed when MSCs from OA patients were cultured on nitrogen (N-rich plasma polymer layers, which we call "PPE:N" (N-doped plasma-polymerized ethylene, containing up to 36 atomic percentage (at.% of N. Methods In the present study, we examined the expression of type X collagen in fetal bovine growth plate chondrocytes (containing hypertrophic chondrocytes cultured on PPE:N. We also studied the effect of PPE:N on the expression of matrix molecules such as type II collagen and aggrecan, as well as on proteases (matrix metalloproteinase-13 (MMP-13 and molecules implicated in cell division (cyclin B2. Two other culture surfaces, "hydrophilic" polystyrene (PS, regular culture dishes and nitrogen-containing cation polystyrene (Primaria®, were also investigated for comparison. Results Results showed that type X collagen mRNA levels were suppressed when cultured for 4 days on PPE:N, suggesting that type X collagen is regulated similarly in hypertrophic chondrocytes and in human MSCs from OA patients. However, the levels of type X collagen mRNA almost returned to control value after 20 days in culture on these surfaces. Culture on the various surfaces had no significant effects on type II collagen, aggrecan, MMP-13, and cyclin B2 mRNA levels. Conclusion Hypertrophy is diminished by culturing growth plate chondrocytes on nitrogen-rich surfaces, a mechanism that is beneficial for MSC chondrogenesis. Furthermore, one major advantage of such "intelligent surfaces" over recombinant growth factors for tissue engineering and cartilage repair is potentially large cost-saving.

  10. Growth inhibition of foodborne pathogens by kimchi prepared with bacteriocin-producing starter culture.

    Science.gov (United States)

    Chang, Ji Yoon; Chang, Hae Choon

    2011-01-01

    Kimchi (starter kimchi) was prepared with Leuconostoc citreum GJ7, a bacteriocin producer, with the objective of preventing growth and/or survival of foodborne pathogens such as Escherichia coli O157:H7, Salmonella Typhi, and Staphylococcus aureus. Numbers of the pathogens inoculated to 5.41 to 5.63 log CFU/mL into the filtrate of freshly made starter kimchi remained stable for the first 12 h of incubation at 10 °C. Reductions of 2.69, 2.88, and 3.42 log CFU/mL were observed 48 h after inoculation with E. coli O157:H7, S. Typhi, and S. aureus, respectively. Use of the bacteriocin-producing starter culture for kimchi fermentation significantly reduced the numbers of pathogens in the filtrate. Reductions of 3.85, 4.45, and 5.19 log CFU/mL were observed 48 h after inoculation for E. coli O157:H7, S. Typhi, and S. aureus, respectively. Presumably, the antimicrobial activity came from the ingredients of kimchi such as sulfur-containing compounds, low pH (approximately pH 4.5) produced by the conversion of sugars into organic acids and the bacteriocins potentially produced by lactic acid bacteria (LAB), such as kimchicin GJ7. Together, these data suggest that addition of a starter culture capable of producing bacteriocins could serve as a strategy to protect the fermented product from delivering pathogens upon consumption and that the kimchi filtrate itself may be used as a food preservative. Practical Application: The adaptation of the starter fermentation into kimchi induced a faster die off of the pathogens as compared to natural fermentation. The in situ bateriocin-production by Leuc. citreum GJ7 in kimchi would act with antimicrobial kimchi ingredients in a synergistic manner to protect the fermented product from delivering pathogens upon consumption.

  11. Growth regulators and darkness increase efficiency in in vitro culture of immature embryos from peppers

    Directory of Open Access Journals (Sweden)

    Juan Pablo Manzur

    2014-12-01

    Full Text Available Common pepper (Capsicum annuum L. is one of the most important vegetables in the world, and extensive breeding efforts are being made to develop new improved strains of this species. In this regard, in vitro culture of immature embryos may help breeders accelerate breeding cycles and overcome interspecific barriers, among other applications. In this study, we have optimized a protocol for in vitro culture of immature embryos of C. annuum. Levels of indole-3-acetic acid (IAA and zeatin have been tested to improve the efficiency (germination rates of this technique in C. annuum embryos at the four main immature stages (i.e. globular, heart, torpedo, and early cotyledonary from four varietal types of this species (California Wonder, Piquillo, Guindilla, and Bola. The effect of 5-day initial incubation in the dark was also tested on the most efficient hormone formulation. On average, relatively low levels of both IAA and zeatin (0.01 mg L−¹ each (M1 provided the highest germination rates, particularly in the advanced stages (torpedo and cotyledonary. To a lesser extent, the lack of these growth regulators (M0 or high IAA (0.2 mg L−¹/low zeatin (0.01 mg L−¹ (M2 combination also had a positive response. On the contrary, high zeatin levels (0.2 mg L−¹ produced very low germination rates or callus development (efficiency 0-7 %. Different responses were also found between genotypes. Thus, considering the best media (M0, M1, M2, Bola embryos had the highest rates. M1 plus 5-days of initial dark incubation (M1-D improved the efficiency rates at all embryo stages, particularly in the earliest (globular embryos which increased from 3 % to > 20 %.

  12. Characterization of connective tissue growth factor expression in primary cultures of human tubular epithelial cells: modulation by hypoxia

    NARCIS (Netherlands)

    Kroening, Sven; Neubauer, Emily; Wullich, Bernd; Aten, Jan; Goppelt-Struebe, Margarete

    2010-01-01

    Kroening S, Neubauer E, Wullich B, Aten J, Goppelt-Struebe M. Characterization of connective tissue growth factor expression in primary cultures of human tubular epithelial cells: modulation by hypoxia. Am J Physiol Renal Physiol 298:F796-F806, 2010. First published December 23, 2009;

  13. Media Compositions for Three Dimensional Mammalian Tissue Growth Under Microgravity Culture Conditions

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    1998-01-01

    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue. The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  14. Media Compositions for Three-Dimensional Mammalian Tissue Growth under Microgravity Culture Conditions

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    1998-01-01

    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue.The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  15. Maternal Cultural Orientation and Child Growth in New Zealand Pacific Families.

    Science.gov (United States)

    Tseng, Marilyn; Taylor, Steve; Tautolo, El-Shadan; Savila, Faasisila; Paterson, Janis; Rush, Elaine

    2015-08-01

    In New Zealand (NZ), children of Pacific heritage are generally born heavier and gain weight more quickly than non-Pacific children. Immigrants' health is commonly expected to converge with the host population through acculturation. The aim of this analysis was to examine whether mothers' acculturation is associated with less-rapid weight gain in NZ Pacific children, and whether this differs by mothers' nativity. In a birth cohort of 1249 children followed 2000-2011, birth weight and weight and standing height, measured at years 2, 4, 6, 9, and 11, were quantified as sex- and age-specific weight (weight-for-age; WFA) and BMI z-scores. Maternal acculturation (range, 11-54) was assessed at baseline and years 4, 6, and 11. In adjusted models using generalized estimating equations to account for repeated measures, maternal acculturation was not significantly associated with children's WFA or BMI z-scores overall. In stratified analyses, change in maternal acculturation score was inversely associated with WFA z-score change among children of NZ-born, but not immigrant, mothers (beta=-0.021; 95% confidence interval, -0.036 to -0.007; p=0.006; interaction, p=0.005). Our study provides the first evidence in a longitudinal sample that changes in maternal acculturation can influence children's growth, suggesting the importance of lifestyle or behavioral factors related to a mother's cultural orientation. Given the high risk of obesity and its related conditions in the NZ Pacific population, critical next steps are to identify mediating factors, as well as to understand the processes influencing growth among children of immigrant mothers.

  16. Intracellular processing of growth hormone receptors by adipocytes in primary culture.

    Science.gov (United States)

    Roupas, P; Herington, A C

    1988-05-01

    Rat adipocytes in primary culture have been used to study the intracellular processing of growth hormone (GH) receptors. Pretreatment of adipocytes with 20 micrograms/ml cycloheximide resulted in a rapid decline (t1/2 approximately 45 min) of the 125I-human growth hormone (hGH) binding capacity of the cells. This decline occurred at a faster rate in the presence of extracellular unlabeled hGH (400 ng/ml) and was not due to receptor occupancy. These data suggest that GH receptors turn over rapidly and constitutively on the plasma membrane and in the absence of protein synthesis are not replaced. Dissociation of GH-receptor complexes was shown not to occur at pH 5.5, the pH encountered in the acidic pre-lysosomal compartments (endosomes) where intracellular dissociation of many hormone-receptor complexes takes place. These data, together, suggest that the majority of GH receptors are not recycled but instead suffer the same fate as the majority of GH, i.e. degradation. To determine the rate of appearance of GH receptors at the cell surface, adipocytes were first treated with trypsin and then incubated at 37 degrees C to permit incorporation of any available GH receptors into the plasma membrane. Binding of 125I-hGH recovered to pre-trypsin levels by 2 h. This recovery was completely blocked by concomitant treatment with monensin, cytochalasin B, colchicine and 2,4-dinitrophenol. NH4Cl had no effect on receptor recovery. These data suggest that once GH receptors are synthesized in the rough endoplasmic reticulum, they travel via the Golgi apparatus to the plasma membrane (by processes involving both microfilaments and microtubules) and are then inserted into the plasma membrane in an energy-dependent step.

  17. GROWTH AND ROOTING SYSTEM OF ACACIA MANGIUM OBTAINED BY TISSUE CULTURE

    Directory of Open Access Journals (Sweden)

    SUPRIYANTO

    1991-01-01

    Full Text Available Since 1980/1981, the government of Indonesia through the Ministry of Forestry has started to reforest logged-over, alang-alang, unproductive areas and to convert them to Forest Industry Plantation. The target is 300 000 ha per year. It means, 750 million seedlings should be provided per year (planting distance 2 m x 2 m. The tree species to be planted in forest industry plantation should have shorter life cycle (8 - 10 years, good stem-form, good rooting system, and should be fast growing. Acacia mangium has been selected as one of the important tree species for forest industry plantation due to its growth, quality of fiber wood (pulp and paper industry and rooting system (produce a lot of secondary root and nitrogen fixater (Soebardjo 1986. The reforestation of logged-over Dipterocarp forests in Malaysia with A. mangium has also been considered (Appanah and Weinland 1989. Generally, reforestation with A. mangium is done with seedlings obtained by seed germination. A. mangium produce a lot of seeds but its production is still limited by the season, while the conventional method of vegetative propagation through cuttings gave very low percentage of rooted-cuttings (1% (Umboh and Syamsul Yani 1989. The micropropagation of A. mangium through tissue culture is a promising method. The production of A. mangium plantlets through that method has been done at the Forest Genetic Laboratory, Tropical Forest Biology, SEAMEO BIOTROP (Situmorang 1988, Umboh 1988, Umboh et al. 1989, 1990. These rooted-plantlets (plantlings were first put in the green house (acclimatization before planting in the field. Field tests of some agricultural plants have been done but information on forest trees species is still lacking because the production of plantlings through tissue culture is still limited as there are still problems of their rooting. In fact, the progress of reproducing woody plants by tissue culture has been much slower than with herbaceous plants. The major

  18. Effects of photoperiod, plant growth regulators and culture media on in vitro growth of seedlings of Cyrtochilum loxense (Lindl. Kraenzl. an endemic and endangered orchid from Ecuador

    Directory of Open Access Journals (Sweden)

    Yadira González

    2014-10-01

    Full Text Available Cyrtochilum loxense (Lindl. Kraenzl. is an endemic and seriously endangered orchid species endemic in the Loja Province (Southern Ecuador. The main goals of this research were to analyze how culture media, plant growth regulators and photoperiod affect the growth of C. loxense. Eight month old plants (approximate 1 – 1.5 cm in height obtained by in vitro germination, were cultivated on MS media or Knudson C; MS with three levels of naphthalene acetic acid (NAA and 6-benzylaminopurine (BAP (2/0.5; 1/0.5 y 0.5/ 0.5 mg-1L; and three photoperiodic regimes (24/0, 16/8, 8/16 h on MS with and without plant growth regulators. No significant differences of shoot induction were observed on media with or without plant growth regulators, and all tested photoperiods. The highest growth (1.2 cm was observed in plantlets cultivated on growth regulator-free media with a 16/8 photoperiod. Also the shoot and root formation was better in this species in absence of plant growth regulators. Probably this response is due to the endogenous hormone levels in the tissues or due to the kind and concentrations of PGRs used were too low to induce positive morphogenetic responses.

  19. Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

    Directory of Open Access Journals (Sweden)

    Chugh Dipti

    2010-05-01

    Full Text Available Abstract Background The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. Results A synthetic insulin precursor (IP-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant. Using immobilized metal ion affinity chromatography (IMAC as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth. Conclusions A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture.

  20. Impact of salinity and growth phase on alkenone distributions in coastal haptophytes

    NARCIS (Netherlands)

    Chivall, D.; M'Boule, D.; Sinke-Schoen, D.; Sinninghe Damsté, J.S.; Schouten, S.; van der Meer, M.T.J.

    2014-01-01

    Batch cultures of Isochrysis galbana (strain CCMP 1323) and Chrysotila lamellosa (strain CCMP 1307) were grown at salinity values of ca. 10 to ca. 35 and the alkenone distributions determined for different growth phases. U-37(K ') values decreased slightly with salinity for C. lamellosa but were

  1. Glycerol as a Cheaper Carbon Source in Bacterial Cellulose (BC) Production by Gluconacetobacter Xylinus DSM46604 in Batch Fermentation System

    International Nuclear Information System (INIS)

    Azila Adnan; Nair, G.R.; Roslan Umar; Roslan Umar

    2015-01-01

    Bacterial cellulose (BC) is a polymer of glucose monomers, which has unique properties including high crystallinity and high strength. It has potential to be used in biomedical applications such as making artificial blood vessel, wound dressings, and in the paper making industry. Extensive study on BC aimed to improve BC production such as by using glycerol as a cheaper carbon source. BC was produced in shake flask culture using five different concentrations of glycerol (10, 20, 30, 40 and 50 g/ L). Using concentration of glycerol above 20 g/ L inhibited culture growth and BC production. Further experiments were performed in batch culture (3-L bioreactor) using 20 g/ L glycerol. It produced yield and productivity of 0.15 g/ g and 0.29 g/ L/ day BC, respectively. This is compared with the control medium, 50 g/ L glucose, which only gave yield and productivity of 0.05 g/ g and 0.23 g/ L/ day, respectively. Twenty g/ L of glycerol enhanced BC production by Gluconacetobacter xylinus DSM46604 in batch fermentation system. (author)

  2. Effect of Different Carbon Sources on Relative Growth Rate, Internal Carbohydrates, and Mannitol 1-Oxidoreductase Activity in Celery Suspension Cultures.

    Science.gov (United States)

    Stoop, JMH.; Pharr, D. M.

    1993-11-01

    Little information exists concerning the biochemical route of mannitol catabolism in higher plant cells. In this study, the role of a recently discovered mannitol 1-oxidoreductase (MDH) in mannitol catabolism was investigated. Suspension cultures of celery (Apium graveolens L. var dulce [Mill.] Pers.) were successfully grown on nutrient media with either mannitol, mannose, or sucrose as the sole carbon source. Cell cultures grown on any of the three carbon sources did not differ in relative growth rate, as measured by packed cell volume, but differed drastically in internal carbohydrate concentration. Mannitol-grown cells contained high concentrations of mannitol and extremely low concentrations of sucrose, fructose, glucose, and mannose. Sucrose-grown cells had high concentrations of sucrose early in the growth cycle and contained a substantial hexose pool. Mannose-grown cells had a high mannose concentration early in the cycle, which decreased during the growth cycle, whereas their internal sucrose concentrations remained relatively constant during the entire growth cycle. Celery suspension cultures on all three carbon substrates contained an NAD-dependent MDH. Throughout the growth cycle, MDH activity was 2- to 4-fold higher in mannitol-grown cells compared with sucrose- or mannose-grown cells, which did not contain detectable levels of mannitol, indicating that MDH functions pre-dominantly in an oxidative capacity in situ. The MDH activity observed in celery cells was 3-fold higher than the minimum amount required to account for the observed rate of mannitol utilization from the media. Cultures transferred from mannitol to mannose underwent a decrease in MDH activity over a period of days, and transfer from mannose to mannitol resulted in an increase in MDH activity. These data provide strong evidence that MDH plays an important role in mannitol utilization in celery suspension cultures.

  3. Growth Performance of Catfish (Clarias Gariepinus Burchell, 1822) Cultured in High Density on the Biofloc System

    Science.gov (United States)

    Basuki, Fajar; Yuniarti, Tristiana; Harwanto, Dicky; Susilowati, Titik

    2018-02-01

    Start your The fish farmers and researchers have made efforts to increase catfish production through high levels of dispersal and application of biofloc systems. This system, in addition to increase production, can also predict when the harvest is done, control the quality of water causing death so that the Survival Rate (SR) is high. The purpose of this study is to determine the growth performance and predict the harvest weight and catfish survival rate (SR) that are cultured with different high density on the biofloc system. The research method used is experimental with test fish in the form of catfish seeds weighing of 8 ± 0.2 gram/fish with each density as treatment: P1. Density of 1,100 fish/m3; P2. Density of 1,200 fish/m3 and P3. Density of 1,300 fish/m3. Pond: The pond used is made of 3m in diameter of tarpaulin, equipped with a 6mm diameter of iron frame. Total volume of water in each pond is 3 m3. Catfish seeds have been adapted and put into the pond at random with the length of cultivation period is 4 weeks. Growth performance analysis uses the SPSS regression statistic series 20. The research results showed that the growth performance for 4 weeks showed that P1 generates the regression equation Y1 = 6.46 +7.81 X with r2 = 0.971 means that if the harvest is done at week 12th then the weight of catfish has reached 100 grams; P2 generates the regression equation Y2 = 6.53 + 6.0 X den r2 = 0.969 means if the harvest is done at week 12th then the weight of new catfish has reached 78.53 grams and P3 generates the regression equation Y3 = 6.71 + 5.94 X with r2 = 0.976 means if harvest is done on week 12th then the weight of new catfish has reached 77.99 grams. Survival rate at P1 = 97.73%; P2 = 95.91% and P3 = 94.55% while the oxygenated water quality is more than 3.5 ppm; pH ranged from 6.7-7 and ammonia content at week 3 is P1 = 0.04 mg/l; P2 = 0.13 mg/l and P3 = 0.27 mg/l.

  4. Prototypical antipsychotic drugs protect hippocampal neuronal cultures against cell death induced by growth medium deprivation

    Directory of Open Access Journals (Sweden)

    Williams Sylvain

    2006-03-01

    Full Text Available Abstract Background Several clinical studies suggested that antipsychotic-based medications could ameliorate cognitive functions impaired in certain schizophrenic patients. Accordingly, we investigated the effects of various dopaminergic receptor antagonists – including atypical antipsychotics that are prescribed for the treatment of schizophrenia – in a model of toxicity using cultured hippocampal neurons, the hippocampus being a region of particular relevance to cognition. Results Hippocampal cell death induced by deprivation of growth medium constituents was strongly blocked by drugs including antipsychotics (10-10-10-6 M that display nM affinities for D2 and/or D4 receptors (clozapine, haloperidol, (±-sulpiride, domperidone, clozapine, risperidone, chlorpromazine, (+-butaclamol and L-741,742. These effects were shared by some caspases inhibitors and were not accompanied by inhibition of reactive oxygen species. In contrast, (--raclopride and remoxipride, two drugs that preferentially bind D2 over D4 receptors were ineffective, as well as the selective D3 receptor antagonist U 99194. Interestingly, (--raclopride (10-6 M was able to block the neuroprotective effect of the atypical antipsychotic clozapine (10-6 M. Conclusion Taken together, these data suggest that D2-like receptors, particularly the D4 subtype, mediate the neuroprotective effects of antipsychotic drugs possibly through a ROS-independent, caspase-dependent mechanism.

  5. Effects of hypoxia condition in embryogenic callus growth of soybean cell culture

    Science.gov (United States)

    Damanik, R. I.; Manurung, B. H.; Bayu, E. S.

    2018-02-01

    The study was performed at Tissue Culture Laboratory, Agrotechnology Department, University of Sumatera Utara, to investigate the effect of plant growth regulator (PGR) and embryogenic callus performance soybean cultivars on hypoxia condition. This research had two stages, induction of embryogenic callus and analysis metabolism of callus after hypoxic condition with T-test. The analysis was used factorial Completely Randomized Design with two factors. The first factors were cultivars of soybean (Baluran, Gepak Kuning, and Grobogan) and the second factors were combinations of PGR (5 mg/l 2,4-D + 1 mg/l BAP, 10 mg/l 2,4-D + 1.5 mg/l BAP, and 15 mg/l 2,4-D + 2 mg/l BAP). The result showed the cultivars, combination of PGR, and interaction between cultivars and PGR gave significant effect to weight callus. The result of T-test showed that in hypoxic condition, POD enzyme exercise on Gepak Kuning’s callus in 5 mg/l 2,4-D + 1 mg/l BAP was different before and after hypoxic condition.

  6. Nanoparticle growth and surface chemistry changes in cell-conditioned culture medium.

    Science.gov (United States)

    Kendall, Michaela; Hodges, Nikolas J; Whitwell, Harry; Tyrrell, Jess; Cangul, Hakan

    2015-02-05

    When biomolecules attach to engineered nanoparticle (ENP) surfaces, they confer the particles with a new biological identity. Physical format may also radically alter, changing ENP stability and agglomeration state within seconds. In order to measure which biomolecules are associated with early ENP growth, we studied ENPs in conditioned medium from A549 cell culture, using dynamic light scattering (DLS) and linear trap quadrupole electron transfer dissociation mass spectrometry. Two types of 100 nm polystyrene particles (one uncoated and one with an amine functionalized surface) were used to measure the influence of surface type. In identically prepared conditioned medium, agglomeration was visible in all samples after 1 h, but was variable, indicating inter-sample variability in secretion rates and extracellular medium conditions. In samples conditioned for 1 h or more, ENP agglomeration rates varied significantly. Agglomerate size measured by DLS was well correlated with surface sequestered peptide number for uncoated but not for amine coated polystyrene ENPs. Amine-coated ENPs grew much faster and into larger agglomerates associated with fewer sequestered peptides, but including significant sequestered lactose dehydrogenase. We conclude that interference with extracellular peptide balance and oxidoreductase activity via sequestration is worthy of further study, as increased oxidative stress via this new mechanism may be important for cell toxicity. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Nutritional Requirements for Mycelial Growth of Milk-White Toothed Mushroom, Irpex lacteus (Agaricomycetes), in Submerged Culture.

    Science.gov (United States)

    Dong, Xiaoming; Song, Xinhua; Dong, Caihong

    2017-01-01

    Irpex lacteus, a medicinal fungus, is used in traditional Chinese medicine to treat chronic glomerulonephritis. In this work, a strain of I. lacteus was isolated from the fruiting body of a wild specimen and identified by ITS-5.8S ribosomal DNA sequencing analysis. Then the nutritional requirements and culture conditions for mycelial growth of I. lacteus in semisynthetic liquid media were investigated using the one-factor-at-a-time and orthogonal matrix methods. Optimum growth occurred at 30°C and 35°C. I. lacteus mycelia grew well at pH values between 3 and 9, suggesting that this strain is not sensitive to pH. The nutritional components, including 9 carbohydrates, 9 nitrogen compounds, 11 vitamins, and 10 mineral elements, were studied for their effects on mycelial growth in submerged cultures of I. lacteus. Among these variables, soluble starch, peptone, yeast extract, and calcium chloride were identified as required for optimum mycelial growth. The concentrations of each component were optimized using an orthogonal design, and the effects of medium composition on mycelial growth were found in the order soluble starch > yeast extract > peptone > calcium chloride. The optimal concentrations of these components for mycelial growth were determined to be 60 g/L soluble starch, 35 g/L peptone, 15 g/L yeast extract, and 0.6 g/L calcium chloride. Under the optimum medium and culture conditions, the maximum biomass reached 13.73 g/L after 3 days in submerged culture, a value over twice that reached using the basal medium. These results provide a basis for further physiological study and industrial fermentation of I. lacteus.

  8. Novel pH control strategy for glutathione overproduction in batch ...

    African Journals Online (AJOL)

    The effects of pH values on cell growth and glutathione (GSH) production were studied in batch cultivation of Candida utilis. According to the fact that lower pH value favors cells growth but retards GSH production and higher pH value promotes GSH production while inhibits cells growth, a pH-shift strategy, optimized via ...

  9. Preparation of cultured skin for transplantation using insulin-like growth factor I in conjunction with insulin-like growth factor binding protein 5, epidermal growth factor, and vitronectin.

    Science.gov (United States)

    Dawson, Rebecca A; Upton, Zee; Malda, Jos; Harkin, Damien G

    2006-06-27

    Cultured skin for transplantation is routinely prepared by growing patient keratinocytes in the presence of semidefined sources of growth factors including serum and feeder cells, but these materials require substantial risk remediation and can contribute to transplant rejection. We have therefore investigated the potential of a novel combination of recombinant and purified growth factors to replace serum and feeder cells in cultures of human keratinocytes suitable for clinical application. Our technique was investigated with respect to culture establishment, serial propagation, colony-forming efficiency, immunocytochemistry, epidermal reconstruction, and suitability to support transplantation by aerosolization. We demonstrate that insulin-like growth factor (IGF)-I--used in conjunction with epidermal growth factor (EGF), insulin-like growth factor binding protein (IGFBP)-5 and vitronectin--supports growth in the absence of serum. Moreover, a threefold greater number of cells are generated within 7 days compared to those grown under current best practice conditions using serum (P<0.05). The resulting test cultures are suitable for epidermal reconstruction and support the option for delivery in the form of an aerosolized cell suspension. Serial propagation, with the view to producing confluent sheets for extensive injuries, was achieved but with less consistency and this result correlated with a significant decline in colony-forming efficiency compared to controls. IGF-I used in conjunction with IGFBP-5, EGF, and vitronectin provides a superior alternative to serum for the rapid expansion and transplantation of cultured keratinocytes within the first week of treatment. Nevertheless, further optimization is required with respect to elimination of feeder cells and serial expansion of cultures for treatment of extensive injuries.

  10. Growth-expectations among women entrepreneurs: embedded in networks and culture in Algeria, Morocco, Tunisia and in Belgium and France

    DEFF Research Database (Denmark)

    Cheraghi, Maryam; Setti, Zakia; Schøtt, Thomas

    2014-01-01

    An entrepreneur usually has an expectation for the firm, expecting expansion, stability or contraction. Expectation is influenced by the entrepreneur's attributes, but expectation is also embedded in the micro-environment of networking and the macro-environment of culture. Traditional culture...... and secular-rational culture differ in roles for women, which influence women entrepreneurs' networking and expectations. The design compares cultures, with data from three traditional societies, Algeria, Morocco and Tunisia and two secular-rational societies, France and Belgium, surveyed in the Global...... Entrepreneurship Monitor, randomly sampling 39,336 women, including 2,306 entrepreneurs. Analyses show that women entrepreneurs have growth-expectations based on their background and increased by their competence and opportunity-motive, which also promote business networks around their firms. Formation...

  11. Artificial neural network-based model for the prediction of optimal growth and culture conditions for maximum biomass accumulation in multiple shoot cultures of Centella asiatica.

    Science.gov (United States)

    Prasad, Archana; Prakash, Om; Mehrotra, Shakti; Khan, Feroz; Mathur, Ajay Kumar; Mathur, Archana

    2017-01-01

    An artificial neural network (ANN)-based modelling approach is used to determine the synergistic effect of five major components of growth medium (Mg, Cu, Zn, nitrate and sucrose) on improved in vitro biomass yield in multiple shoot cultures of Centella asiatica. The back propagation neural network (BPNN) was employed to predict optimal biomass accumulation in terms of growth index over a defined culture duration of 35 days. The four variable concentrations of five media components, i.e. MgSO 4 (0, 0.75, 1.5, 3.0 mM), ZnSO 4 (0, 15, 30, 60 μM), CuSO 4 (0, 0.05, 0.1, 0.2 μM), NO 3 (20, 30, 40, 60 mM) and sucrose (1, 3, 5, 7 %, w/v) were taken as inputs for the ANN model. The designed model was evaluated by performing three different sets of validation experiments that indicated a greater similarity between the target and predicted dataset. The results of the modelling experiment suggested that 1.5 mM Mg, 30 μM Zn, 0.1 μM Cu, 40 mM NO 3 and 6 % (w/v) sucrose were the respective optimal concentrations of the tested medium components for achieving maximum growth index of 1654.46 with high centelloside yield (62.37 mg DW/culture) in the cultured multiple shoots. This study can facilitate the generation of higher biomass of uniform, clean, good quality C. asiatica herb that can efficiently be utilized by pharmaceutical industries.

  12. Socioeconomic Growth, Culture Scale, and Household Well-Being. A Test of the Power-Elite Hypothesis.

    Science.gov (United States)

    Bodley

    1999-12-01

    Socioeconomic growth is an elite-directed process that concentrates social power in direct proportion to increases in culture scale. Power elites have controlled social power to their own advantage in at least three different ways: domestically, by means of kinship, politically, by means of rulers, and commercially, by means of the market. Each method produces its own growth trajectory and scale of culture and a distinctive distribution of elite power and household living standards. Ethnographic data on urban property ownership in 27 municipalities in the Palouse region of eastern Washington suggest that when power is commercially organized and villages become towns and cities, there is a dramatic increase not only in the number of prosperous households but even more in the number of poor and maintenance-level households. Elite property owners, who most benefit from growth, assume a larger role in municipal government, where they can encourage further growth through municipal annexations and zoning changes. Thus, as elite power becomes increasingly concentrated, the growth process itself tends to become self-perpetuating. In the Palouse example, small, no-growth municipalities appear to be politically more democratic than larger-scale, growing municipalities and household well-being in them more equitably distributed.

  13. Diauxic Growth of Propionibacterium shermanii

    Science.gov (United States)

    Lee, Inn Hee; Fredrickson, A. G.; Tsuchiya, H. M.

    1974-01-01

    Propionibacterium shermanii has been anaerobically propagated in batch and continuous culture with glucose and/or lactate as energy source. Specific growth rate on lactate was observed to be the same as that on glucose. In terms of cell density, the yield on glucose is higher than the yield on lactate. But the molar ratio of yield on glucose to that on lactate, 8.35, is in good agreement with the theoretical value of 8. In a mixture of glucose and lactate, P. shermanii showed diauxic growth. It used lactate before glucose utilization began. Neither temporary growth cessation nor two distinct growth phases were observed. A mathematical model is proposed to describe the diauxic growth. PMID:4441064

  14. Influence of culture media, pH and temperature on growth and bacteriocin production of bacteriocinogenic lactic acid bacteria.

    Science.gov (United States)

    Yang, En; Fan, Lihua; Yan, Jinping; Jiang, Yueming; Doucette, Craig; Fillmore, Sherry; Walker, Bradley

    2018-01-24

    There has been continued interest in bacteriocins research from an applied perspective as bacteriocins have potential to be used as natural preservative. Four bacteriocinogenic lactic acid bacteria (LAB) strains of Lactobacillus curvatus (Arla-10), Enterococcus faecium (JFR-1), Lactobacillus paracasei subsp. paracasei (JFR-5) and Streptococcus thermophilus (TSB-8) were previously isolated and identified in our lab. The objective of this study was to determine the optimal growth conditions for both LAB growth and bacteriocins production. In this study, various growth conditions including culture media (MRS and BHI), initial pH of culture media (4.5, 5.5, 6.2, 7.4 and 8.5), and incubation temperatures (20, 37 and 44 °C) were investigated for LAB growth measured as optical density (OD), bacteriocin activity determined as arbitrary unit and viability of LAB expressed as log CFU ml -1 . Growth curves of the bacteriocinogenic LAB were generated using a Bioscreen C. Our results indicated that Arla-10, JFR-1, and JFR-5 strains grew well on both MRS and BHI media at growth temperature tested whereas TSB-8 strain, unable to grow at 20 °C. LAB growth was significantly affected by the initial pH of culture media (p < 0.001) and the optimal pH was found ranging from 6.2 to 8.5. Bacteriocin activity was significantly different in MRS versus BHI (p < 0.001), and the optimal condition for LAB to produce bacteriocins was determined in MRS broth, pH 6.2 at 37 °C. This study provides useful information on potential application of bacteriocinogenic LAB in food fermentation processes.

  15. The micro-Petri dish, a million-well growth chip for the culture and high-troughput screening of microorganisms

    NARCIS (Netherlands)

    Ingham, C.J.; Sprenkels, A.J.; Bomer, Johan G.; Molenaar, D.; van den Berg, Albert; van Hylckama Vlieg, J.E.T.; de Vos, W.M.

    2007-01-01

    A miniaturized, disposable microbial culture chip has been fabricated by microengineering a highly porous ceramic sheet with up to one million growth compartments. This versatile culture format, with discrete compartments as small as 7 x 7 mu m, allowed the growth of segregated microbial samples at

  16. From the cover: the micro-petri dish, a million-well growth chip for the culture and high-throughput screening of microorganisms

    NARCIS (Netherlands)

    Ingham, C.J.; Sprenkels, A.; Bomer, J.; Molenaar, D.; Berg, van den Aad; Hylckama Vlieg, van J.E.T.; Vos, de W.M.

    2007-01-01

    A miniaturized, disposable microbial culture chip has been fabricated by microengineering a highly porous ceramic sheet with up to one million growth compartments. This versatile culture format, with discrete compartments as small as 7 x 7 µm, allowed the growth of segregated microbial samples at an

  17. THE IMPACT OF CULTURAL-CREATIVE INDUSTRIES ON THE ECONOMIC GROWTH – A QUANTITATIVE APPROACH

    Directory of Open Access Journals (Sweden)

    Titan Emilia

    2008-05-01

    Full Text Available Culture is a powerful tool to communicate values and to promote objectives of public interest that are broader than wealth creation. The economy of culture entails both cultural and creative sectors. It has to be noted that, along with the development of the information and communication technology (ICT sector, the contribution of culture to the economy has gradually been acknowledged, in particular with the development of the cultural industries. One way of measuring the economy of culture focuses on the value added to the economy. Also, we present several statistical indicators that quantify the dimension of the cultural-creative field, and identify an econometrical multiple model that reveals the relationship between some of them. In the article it is applied the analysis of variance method in order to identify the existence of significant differences between geographical and between linguistic-cultural European regions, according to the values of some of the statistical indicators.

  18. Three-dimensional in vitro follicle growth: overview of culture models, biomaterials, design parameters and future directions.

    Science.gov (United States)

    Desai, Nina; Alex, Anastasia; AbdelHafez, Faten; Calabro, Anthony; Goldfarb, James; Fleischman, Aaron; Falcone, Tommaso

    2010-10-14

    In vitro ovarian follicle culture is a new frontier in assisted reproductive technology with tremendous potential, especially for fertility preservation. Folliculogenesis within the ovary is a complex process requiring interaction between somatic cell components and the oocyte. Conventional two-dimensional culture on tissue culture substrata impedes spherical growth and preservation of the spatial arrangements between oocyte and surrounding granulosa cells. Granulosa cell attachment and migration can leave the oocyte naked and unable to complete the maturation process. Recognition of the importance of spatial arrangements between cells has spurred research in to three-dimensional culture system. Such systems may be vital when dealing with human primordial follicles that may require as long as three months in culture. In the present work we review pertinent aspects of in vitro follicle maturation, with an emphasis on tissue-engineering solutions for maintaining the follicular unit during the culture interval. We focus primarily on presenting the various 3-dimensional culture systems that have been applied for in vitro maturation of follicle:oocyte complexes. We also try to present an overview of outcomes with various biomaterials and animal models and also the limitations of the existing systems.

  19. Polyamine levels as related to growth, differentiation and senescence in protoplast-derived cultures of Vigna aconitifolia and Avena sativa

    Science.gov (United States)

    Kaur Sawhney, R.; Shekhawat, N. S.; Galston, A. W.

    1985-01-01

    We have previously reported that aseptically cultured mesophyll protoplasts of Vigna divide rapidly and regenerate into complete plants, while mesophyll protoplasts of Avena divide only sporadically and senesce rapidly after isolation. We measured polyamine titers in such cultures of Vigna and Avena, to study possible correlations between polyamines and cellular behavior. We also deliberately altered polyamine titer by the use of selective inhibitors of polyamine biosynthesis, noting the effects on internal polyamine titer, cell division activity and regenerative events. In Vigna cultures, levels of free and bound putrescine and spermidine increased dramatically as cell division and differentiation progressed. The increase in bound polyamines was largest in embryoid-forming callus tissue while free polyamine titer was highest in root-forming callus. In Avena cultures, the levels of total polyamines decreased as the protoplast senesced. The presence of the inhibitors alpha-difluoromethyl-arginine (specific inhibitor of arginine decarboxylase), alpha-difluoromethylornithine (specific inhibitor of ornithine decarboxylase) and dicyclohexylamine (inhibitor of spermidine synthase) reduced cell division and organogenesis in Vigna cultures. Addition of low concentration of polyamines to such cultures containing inhibitors or removal of inhibitors from the culture medium restored the progress of growth and differentiation with concomitant increase in polyamine levels.

  20. Acid tolerance in Salmonella typhimurium induced by culturing in the presence of organic acids at different growth temperatures.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Fernández, Ana; Bernardo, Ana; López, Mercedes

    2010-02-01

    The influence of growth temperature and acidification of the culture medium up to pH 4.25 with acetic, citric, lactic and hydrochloric acids on the growth and subsequent acid resistance at pH 3.0 of Salmonella typhimurium CECT 443 was studied. The minimum pH value which allowed for S. typhimurium growth within the temperature range of 25-37 degrees C was 4.5 when the pH was reduced using citric and hydrochloric acids, and 5.4 and 6.4 when lactic acid and acetic acid were used, respectively. At high (45 degrees C) or low (10 degrees C) temperatures, the growth pH boundary was increased about 1 pH unit. The growth temperature markedly modified the acid resistance of the resulting cells. In all cases, D-values were lower for cells grown at 10 degrees C and significantly increased with increasing growth temperature up to 37 degrees C, at which D-values obtained were up to 10 times higher. Cells grown at 45 degrees C showed D-values similar to those found for cells grown at 25 degrees C. The growth of cells in acidified media, regardless of the pH value, caused an increase in their acid resistance at the four incubation temperatures, although the magnitude of the Acid Tolerance Response (ATR) observed depended on the growth temperature. Acid adapted cultures at 10 degrees C showed D-values ranging from 5.75 to 6.91 min, which turned out to be about 2 times higher than those corresponding to non-acid adapted cultures, while higher temperatures induced an increase in D-values of at least 3.5 times. Another finding was that, while at 10 and 45 degrees C no significant differences among the effect of the different acids tested in inducing an ATR were observed, when cells were grown at 25 and 37 degrees C citric acid generally turned out to be the acid which induced the strongest ATR. Results obtained in this study show that growth temperature is an important factor affecting S. typhimurium acid resistance and could contribute to find new strategies based on intelligent

  1. Plasma Membrane Proteomics of Arabidopsis Suspension-Cultured Cells Associated with Growth Phase Using Nano-LC-MS/MS.

    Science.gov (United States)

    Li, Bin; Takahashi, Daisuke; Kawamura, Yukio; Uemura, Matsuo

    2018-01-01

    Arabidopsis thaliana suspension-cultured cells (T87 line) are important model system for studies of responses to biotic and abiotic stresses at the cellular level in vitro since the cells have certain advantages compared with the whole plant system. However, the physiological and morphological characteristics of the cells are influenced by the progress of the growth phase of cells, which may result in different stress tolerance. To obtain comprehensive proteome profiles of the plasma membrane of Arabidopsis thaliana T87 suspension-cultured cells at the lag, log, or stationary growth phase, a shotgun proteomics method using nano-LC-MS/MS is used. The results obtained indicate that proteome profiles of the plasma membrane with the progress of the growth phase of cells dynamically changed, which may be associated with the physiological and morphological characteristics of the plasma membrane of the suspension-cultured cells. The proteomics results are further applied to explain different responsive patterns in the plasma membrane to cold acclimation and ABA treatment, which lead to understanding of different freezing tolerance associated with the growth phase of the cells.

  2. Long-term culture of sponge explants: conditions enhancing survival and growth, and assessment of bioactivity

    NARCIS (Netherlands)

    Caralt, de S.; Agell, G.; Uriz, M.J.

    2003-01-01

    Sponges are an important source of secondary metabolites with pharmaceutical interest. This is the main reason for the increasing interest of sponge culture recent years. The optimal culture system depends on the species to be cultured: while some species easily produce sponge aggregates after

  3. The chalcone butein from Rhus verniciflua Stokes inhibits clonogenic growth of human breast cancer cells co-cultured with fibroblasts

    Directory of Open Access Journals (Sweden)

    Tan Jenny

    2005-03-01

    Full Text Available Abstract Background Butein (3,4,2',4'-tetrahydroxychalone, a plant polyphenol, is a major biologically active component of the stems of Rhus verniciflua Stokes. It has long been used as a food additive in Korea and as an herbal medicine throughout Asia. Recently, butein has been shown to suppress the functions of fibroblasts. Because fibroblasts are believed to play an important role in promoting the growth of breast cancer cells, we investigated the ability of butein to inhibit the clonogenic growth of small numbers of breast cancer cells co-cultured with fibroblasts in vitro. Methods We first measured the clonogenic growth of small numbers of the UACC-812 human breast cancer cell line co-cultured on monolayers of serum-activated, human fibroblasts in the presence of butein (2 μg/mL or various other modulators of fibroblast function (troglitazone-1 μg/mL; GW9662-1 μM; meloxican-1 μM; and 3,4 dehydroproline-10 μg/mL. In a subsequent experiment, we measured the dose-response effect on the clonogenic growth of UACC-812 breast cancer cells by pre-incubating the fibroblasts with varying concentrations of butein (10 μg/ml-1.25 μg/mL. Finally, we measured the clonogenic growth of primary breast cancer cells obtained from 5 clinical specimens with normal fibroblasts and with fibroblasts that had been pre-treated with a fixed dose of butein (2.5 μg/mL. Results Of the five modulators of fibroblast function that we tested, butein was by far the most potent inhibitor of clonogenic growth of UACC-812 breast cancer cells co-cultured with fibroblasts. Pre-treatment of fibroblasts with concentrations of butein as low as 2.5 μg/mL nearly abolished subsequent clonogenic growth of UACC-812 breast cancer cells co-cultured with the fibroblasts. A similar dose of butein had no effect on the clonogenic growth of breast cancer cells cultured in the absence of fibroblasts. Significantly, clonogenic growth of the primary breast cancer cells was also

  4. Metabolic effects of growth factors and polycyclic aromatic hydrocarbons on cultured human placental cells of early and late gestation

    International Nuclear Information System (INIS)

    Guyda, H.J.

    1991-01-01

    The metabolic effects of epidermal growth factor (EGF), insulin, insulin-like growth factor-I (IGF-I), and IGF-II were determined on human placental cells in monolayer culture obtained from early gestation (less than 20 weeks) and late gestation (38-42 weeks). Parameters studied were uptake of aminoisobutyric acid (AIB), uptake of 3-O-methylglucose and [3H]thymidine incorporation into cell protein. Since benzo[alpha]pyrene (BP) inhibits EGF binding and autophosphorylation in cultured human placental cells, particularly in early gestation, we also studied the effect of benzo[alpha]pyrene and other polycyclic aromatic hydrocarbons (PAHs) on EGF-mediated AIB uptake. The metabolic effects of EGF, insulin, and the IGFs in cultured human placental cells varied with gestational age and the growth factor studied. All three classes of growth factors stimulated AIB uptake in both early and late gestation at concentrations from 10-100 micrograms/L, well within a physiological range. However, insulin stimulation of AIB uptake was maximal at a high concentration in both early and late gestation cells, suggesting an action via type 1 IGF receptors rather than via insulin receptors. EGF stimulated 3-O-methylglucose uptake only in term placental cells. No significant stimulation of [3H]thymidine incorporation by any of the growth factors tested was seen with either early or late gestation cells. The effect of PAHs on AIB uptake by cultured placental cells was variable. BP alone stimulated AIB uptake by both very early and late gestation cells and enhanced EGF-stimulated AIB uptake. alpha-naphthoflavone alone inhibited AIB uptake at all gestational ages and inhibited EGF-stimulated AIB uptake. beta-Naphthoflavone and 3-methylcholanthrene minimally inhibited AIB uptake by early gestation cells and did not modify EGF-stimulated uptake at any gestational period

  5. Anti-Müllerian hormone reduces growth rate without altering follicular survival in isolated caprine preantral follicles cultured in vitro.

    Science.gov (United States)

    Rocha, R M P; Lima, L F; Brito, I R; Silva, G M; Correia, H H V; Ribeiro de Sá, N A; Ferreira, A C A; Sales, A D; Lobo, C H; Campello, C C; Smitz, J; Wheeler, M B; Figueiredo, J R

    2017-06-01

    The aim of the present study was to evaluate the effect of anti-Müllerian hormone (AMH), with and without FSH, on the in vitro development of isolated caprine preantral follicles, as well as follicular steroid production and mRNA levels of AMH, hormone receptors (AMH and FSH), CYP19A1 (cytochrome P450, family 19, subfamily A, polypeptide 1), CYP17 (cytochrome P450, family 17, subfamily A, polypeptide 1), HSD3B (3-beta-hydroxysteroid dehydrogenase) and Myc (myelocytomatosis oncogene). Isolated secondary follicles were cultured in minimum essential medium alpha (α-MEM+) alone or supplemented with 50ng mL -1 AMH and/or 100ng mL -1 FSH added sequentially on different days of culture. Follicles were cultured for a total of 18 days, with different media during the first (Days 0-9) and second (Days 10-18) halves of the culture period, resulting in six treatment groups, as follows: α-MEM+/α-MEM+, FSH/FSH, AMH/AMH, AMH+FSH/AMH+FSH, AMH/FSH, and FSH/AMH. Follicle development was evaluated on the basis of follicular growth, oocyte maturation and steroid secretion. There was a decrease in follicular growth rate in the AMH, AMH+FSH and AMH/FSH treatment groups compared with α-MEM+ and FSH treatment groups (Prates of meiotic resumption and steroid secretion (P>0.05). Moreover, follicles cultured in the presence of FSH had lower levels of AMH receptor type II (AMHRII) mRNA compared with non-cultured control (freshly isolated follicles), and the AMH and AMH/FSH treatment groups. In conclusion, AMH reduces the follicular growth rate of isolated goat preantral follicles in vitro without affecting follicular survival.

  6. Expression of the human growth hormone variant gene in cultured fibroblasts and transgenic mice

    International Nuclear Information System (INIS)

    Selden, R.F.; Wagner, T.E.; Blethen, S.; Yun, J.S.; Rowe, M.E.; Goodman, H.M.

    1988-01-01

    The nucleotide sequence of the human growth hormone variant gene, one of the five members of the growth hormone gene family, predicts that it encodes a growth hormone-like protein. As a first step in determining whether this gene is functional in humans, the authors have expressed a mouse methallothionein I/human growth hormone variant fusion gene in mouse L cells and in transgenic mice. The growth hormone variant protein expressed in transiently transfected L cells is distinct from growth hormone itself with respect to reactivity with anti-growth hormone monoclonal antibodies, behavior during column chromatography, and isoelectric point. Transgenic mice expressing the growth hormone variant protein are 1.4- to 1.9-fold larger than nontransgenic controls, suggesting that the protein has growth-promoting properties

  7. Novel relationships of growth factors to the G1/S transition in cultured astrocytes from rat forebrain.

    Science.gov (United States)

    Langan, T J; Slater, M C; Kelly, K

    1994-01-01

    The cell cycle encompasses the sequential events regulating cell division. In mammalian brain, initiation of astrocyte cycling is critical during development and injury. To investigate the timing of growth factor requirements as they commit to passing through the G1 phase, primary and secondary rat astrocytes were stimulated to enter the cycle after serum or growth factor deprivation. Bromodeoxyuridine immunofluorescence was used to monitor S phase nuclei after growth factor re-addition (at time 0). Cycle kinetics were identical whether quiescent cultures were exposed to 10% (vol/vol) calf serum, or to a defined medium containing fibroblast growth factor, insulin, and epidermal growth factor. The control point in late G1 that represents commitment to achieving the G1/S transition was identified by cycloheximide (CHX, 0.1 microgram/ml) addition. Sensitivity to cycle arrest by CHX disappeared at 9-10 h. In contrast, shift-down to growth factor-deficient medium arrested cell cycling virtually until G1/S (12 h). With selective exposure during late G1 (9-12 h), no single agent permitted cycle progression. However, any two agents enabled cycling, and complementary or synergistic effects were apparent. These requirements were identical in astroglia from newborn and long-term cultures. Thus, temporal dissociation exists between the processes of escape from CHX sensitivity and from requirements for growth factors, two recognized hallmarks of commitment to cycle progression. Furthermore, simultaneous presence of at least two growth factors is necessary at or near G1/S. Both findings distinguish astrocytes from several other cell types.

  8. Insulin receptors mediate growth effects in cultured fetal neurons. I. Rapid stimulation of protein synthesis

    International Nuclear Information System (INIS)

    Heidenreich, K.A.; Toledo, S.P.

    1989-01-01

    In this study we have examined the effects of insulin on protein synthesis in cultured fetal chick neurons. Protein synthesis was monitored by measuring the incorporation of [3H]leucine (3H-leu) into trichloroacetic acid (TCA)-precipitable protein. Upon addition of 3H-leu, there was a 5-min lag before radioactivity occurred in protein. During this period cell-associated radioactivity reached equilibrium and was totally recovered in the TCA-soluble fraction. After 5 min, the incorporation of 3H-leu into protein was linear for 2 h and was inhibited (98%) by the inclusion of 10 micrograms/ml cycloheximide. After 24 h of serum deprivation, insulin increased 3H-leu incorporation into protein by approximately 2-fold. The stimulation of protein synthesis by insulin was dose dependent (ED50 = 70 pM) and seen within 30 min. Proinsulin was approximately 10-fold less potent than insulin on a molar basis in stimulating neuronal protein synthesis. Insulin had no effect on the TCA-soluble fraction of 3H-leu at any time and did not influence the uptake of [3H]aminoisobutyric acid into neurons. The isotope ratio of 3H-leu/14C-leu in the leucyl tRNA pool was the same in control and insulin-treated neurons. Analysis of newly synthesized proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that insulin uniformly increased the incorporation of 14C-leu into all of the resolved neuronal proteins. We conclude from these data that (1) insulin rapidly stimulates overall protein synthesis in fetal neurons independent of amino acid uptake and aminoacyl tRNA precursor pools; (2) stimulation of protein synthesis is mediated by the brain subtype of insulin receptor; and (3) insulin is potentially an important in vivo growth factor for fetal central nervous system neurons

  9. Development of a cell-derived matrix: effects of epidermal growth factor in chemically defined culture.

    Science.gov (United States)

    Throm, Angela M; Liu, Wai-Ching; Lock, Chi-Hung; Billiar, Kristen L

    2010-02-01

    Extracellular matrices without animal components and with high mechanical strength are needed for the development of the next generation of viable skin replacements. The goal of this study was to determine the optimal concentration of epidermal growth factor (EGF) to maximize the strength and collagen content of cell-derived matrix (CDM) produced by fibroblasts in vitro in serum-free media. Scaffold-free CDM samples were produced by human dermal fibroblasts in the presence of 0-50 ng/mL EGF in chemically defined media. After 21 days of culture, a membrane inflation system was used to measure the biaxial tensile strength, failure stretch ratio, and thickness of each treatment group. The fibroblasts treated with 5 ng/mL EGF produced the thickest matrix (270 microm). A thinner (130 microm) matrix, produced when the fibroblasts were treated with 0.5 ng/mL, had an ultimate tensile strength (895 kPa), greater than two times that of the other treatment groups. The fibroblasts treated with 0.5 ng/mL also had the highest collagen density (23.5 mg/cm(3)). Fibroblasts stimulated with the lowest (0.05 ng/mL) and highest (50 ng/mL) concentrations of EGF produced significantly weaker matrices and lower collagen densities. There was no significant correlation between UTS and collagen density suggesting that mechanisms other than density contribute to the strength of the matrix. Taken together, these data indicate that the optimal EGF concentration depends upon the relative importance of matrix strength and volume in a given application and that 0.5-5.0 ng/mL EGF promotes production of a robust extracellular matrix in only 3 weeks. (c) 2009 Wiley Periodicals, Inc.

  10. Feasibility, density and growth of culture of freshwater crayfish (Decapoda: Cherax Quadricarinatus in Sinaloa, México

    Directory of Open Access Journals (Sweden)

    Juan Francisco Arzola González

    2012-09-01

    Full Text Available Feasibility, density and growth of culture of freshwater crayfish (Cherax quadricarinatus in Sinaloa were analyzed between September, 2005 and January, 2006. The densities were 7 (reservoir 1 and 16 (reservoir 2 org/m-2. Applied a method not parametrico (Kruskal-Wallis, the variables of response were density, weight and sex, the experimental unit the reservoirs. Samplings were weekly and 40 lobsters were captured in tubes of PVC. Total and cefalotorácica length ((LT y LC in mm and total weight (PT in g of the organisms were recorded, the biometric correlations were realized and von Bertalanffy estimated the growth for the model of von Bertallanfy. The major average was obtained in 41.2 g to a density of 7 org/m, though her k (growth rate coincided with the reservoirs with 0.30, in addition, the lobsters they presented a growth of isometric type. From the first year, usefulness of $3,419,165.00 obtained, that represented 26.8 % of the total of income, keeping a growth like that supported until the fifth year (2011. The financial evaluation determined that the investment is profitable economically, his analysis of VAN was $9,060,554.00, and in agreement to the financial indicators, this value was ideal for the accomplishment of the project. As indicator of the profitability, the TIR resulted in 66 %, being major that the minimal acceptable rate of performance and concluding the profitability of the culture in 59 %. Likewise, Sinaloa's condition, for his geographical location and the results ofthe growth, the heights, the performance of the lobster and of the financial analysis of the culture, indicated to C. quadricarinatusas an alternative of development in the region, being the lobster of interest in acuiculture of new species in tropical areas, thoughin Sinaloa the investigations are practically void with ends of commercial production.

  11. Transcriptional response of P. pastoris in fed-batch cultivations to Rhizopus oryzae lipase production reveals UPR induction

    Directory of Open Access Journals (Sweden)

    Valero Francisco

    2007-07-01

    Full Text Available Abstract Background The analysis of transcriptional levels of the genes involved in protein synthesis and secretion is a key factor to understand the host organism's responses to recombinant protein production, as well as their interaction with the cultivation conditions. Novel techniques such as the sandwich hybridization allow monitoring quantitatively the dynamic changes of specific RNAs. In this study, the transcriptional levels of some genes related to the unfolded protein response (UPR and central metabolism of Pichia pastoris were analysed during batch and fed-batch cultivations using an X-33-derived strain expressing a Rhizopus oryzae lipase under control of the formaldehyde dehydrogenase promoter (FLD1, namely the alcohol oxidase gene AOX1, the formaldehyde dehydrogenase FLD1, the protein disulfide isomerase PDI, the KAR2 gene coding for the BiP chaperone, the 26S rRNA and the R. oryzae lipase gene ROL. Results The transcriptional levels of the selected set of genes were first analysed in P. pastoris cells growing in shake flask cultures containing different carbon and nitrogen sources combinations, glycerol + ammonium, methanol + methylamine and sorbitol + methylamine. The transcriptional levels of the AOX1 and FLD1 genes were coherent with the known regulatory mechanism of C1 substrates in P. pastoris, whereas ROL induction lead to the up-regulation of KAR2 and PDI transcriptional levels, thus suggesting that ROL overexpression triggers the UPR. This was further confirmed in fed-batch cultivations performed at different growth rates. Transcriptional levels of the analysed set of genes were generally higher at higher growth rates. Nevertheless, when ROL was overexpressed in a strain having the UPR constitutively activated, significantly lower relative induction levels of these marker genes were detected. Conclusion The bead-based sandwich hybridization assay has shown its potential as a reliable instrument for quantification of

  12. Influence of genotype, growth regulators, sucrose level and preconditioning of donor plants on flax (Linum usitatissimum L.) anther culture.

    Science.gov (United States)

    Burbulis, Natalija; Blinstrubiene, Ausra; Sliesaravicius, A; Venskutoniene, Egidija

    2005-01-01

    The effect of genotype, growth regulators and preconditioning of donor plants on callus induction in anther culture of flax was investigated. Anthers were cultured on modified MS medium supplemented with five different combinations of plant growth regulators. The results suggested that specific combinations of growth regulators must be designed for each genotype. Major differences between the present results and previous reports are discussed. The influence of sucrose concentration was also investigated. For flax cultivar, 'Mikael', callus induction was higher in medium supplemented with 1 mg l(-1) BAP and 2 mg l(-1) 2,4D containing 6% sucrose, while this combination of growth regulators significantly increased callogenesis in cultivars 'Lirina', 'Barbara' and 'Szaphir' when supplemented with 9% or 12% sucrose. The preconditioning of donor plants influenced callogenesis in subsequently isolated anthers. Anthers from donor plants grown at a lower temperature (18/14 degrees C) significantly increased callus induction over those from plants grown at a higher temperature (22/18 degrees C), although each genotype still required optimization of growth regulator combinations in the induction medium. Only 'Mikael' regenerated shoots when the callus was from induction medium supplemented with 2 mg I(-1) BAP and 1 mg l(-1) NAA.

  13. The Effect of Plant Growth Regulators and Different Explants on the Response of Tissue Culture and Cell Suspension Cultures of German Chamomile (Matricaria chamomilla L.

    Directory of Open Access Journals (Sweden)

    L. Koohi,

    2014-07-01

    Full Text Available German chamomile (Matricaria chamomilla L. is one of the most important medicinal plants that its essential oils used in different medicinal industries. In this study which was carried out in 2013 growing season at the Faculty of Agricultural Sciences of the University of Mohaghegh Ardabili, the in vitro response of leaf and hypocotyl explants of German Chamomile in B5 medium supplemented with different levels of plant growth regulators including 2,4-D, naphthalene acetic acid (NAA, kinetin and 6-benzylaminopurine (BAP were investigated in a factorial experiment based on completely randomized design (CRD.In addition, cell suspension cultures were established and characterized. Hypocotyl and leaf explants exhibited cell proliferation and produced callus within 1-2 weeks. The highest fresh weight of the callus (264.1 mg was produced by leaf explants in the medium supplemented with 0.5 mg/l 2,4-D and 1 mg/l BAP. However, the leaf explants cultured on medium containing 1.5 mg/l 2,4-D showed the lowest cell proliferation and callus yield (40.42 mg. The highest percentage of root induction from leaf explants (58.73% was observed on the medium containing 4 mg/l 2,4-D and 1 mg/l Kin, and from hypocotyl explants (48.61% was observed on medium supplemented with 1.5 mg/l NAA. The 42.22% of calli derived from hypocotyl explants on B5 medium supplemented with 4 mg/l NAA and 3 mg/l BAP, were friable. Cell suspension cultures of German chamomile were established by transferring of hypocotyl-derived friable calli into the MS medium supplemented with 1.5 mg/l 2,4-D and 1 mg/l kinetin. The growth curve of cell proliferations started 4 days after culture and continued to grow until day 13th, where the cells entered stationary phase.

  14. Analysis of the growth pattern of Vero cells cultured on dense and porous poly (L-Lactic Acid scaffolds

    Directory of Open Access Journals (Sweden)

    Arnaldo Rodrigues Santos Jr

    2009-09-01

    Full Text Available Poly (L-lactic acid (PLLA polymers are the most frequently used substrates for cell culture, tissue regeneration and orthopedic prostheses, mainly because of their atoxic characteristics and good biocompatibility. The objective of this study was to evaluate whether a higher density or different pore diameters (less than 45, 180-250, and 250-350 µm would change the growth pattern of cultured cells. The cells were found to adhere to and spread over all PLLA scaffolds studied. The cells also showed similar proliferation on dense and porous PLLA scaffolds, except for PLLA scaffolds with a smaller pore diameter. The cytochemical data showed high metabolic cellular activity on the various substrates. Overall, the results indicated satisfactory cell growth and proliferation on the different PLLA scaffolds studied, especially for those with pore diameters of 180-250 µm and 250-350 µm.

  15. Interaction between Lactococcus lactis and Lactococcus raffinolactis during growth in milk: development of a new starter culture.

    Science.gov (United States)

    Kimoto-Nira, H; Aoki, R; Mizumachi, K; Sasaki, K; Naito, H; Sawada, T; Suzuki, C

    2012-04-01

    Many milk fermentations use mixed cultures of lactic acid bacteria. To select a new mixed starter culture, 100 acid-producing bacterial strains were isolated from raw cow milk. Of these, 13 strains identified as belonging to the genera Lactococcus, Lactobacillus, Leuconostoc, or Weissella (based on phenotypic and genotypic tests) were assessed for a symbiotic effect between pairs of isolated strains during growth in milk. Among the strains tested, a mixed culture of Lactococcus lactis ssp. lactis strain 54 and Lactococcus raffinolactis strain 37 stimulated greater acid production during fermentation than occurred with pure fermentation. This stimulatory effect was not observed in milk supplemented with yeast extract or glucose or in constituted medium. Addition of a cell-free filtrate from milk fermented by strain 54 increased acid production by strain 37; however, the converse effect was not observed. The increased acid production by this mixed culture was, therefore, due to stimulation of strain 37 by metabolic products of strain 54, suggesting that the interaction between strains 54 and 37 is commensal. Analysis with a taste-sensing system indicated that fermented milk containing the mixed culture was more acidic, had more anionic bitterness, had greater aftertastes of anionic bitterness and astringency, and was less salty and umami than milk containing the individual cultures. This study identifies a new commensal relationship between 2 lactococcal strains that are commonly used for making dairy products. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Family based dispatching with batch availability

    NARCIS (Netherlands)

    van der Zee, D.J.

    2013-01-01

    Family based dispatching rules seek to lower set-up frequencies by grouping (batching) similar types of jobs for joint processing. Hence shop flow times may be improved, as less time is spent on set-ups. Motivated by an industrial project we study the control of machines with batch availability,

  17. Automatic endpoint determination for batch tea dryers

    NARCIS (Netherlands)

    Temple, S.J.; Boxtel, van A.J.B.

    2001-01-01

    A laboratory batch fluid-bed dryer was developed for handling small samples of tea for experimental batch manufacture, and this dryer required a means of stopping drying when the process was complete. A control system was devised which requires only the initial weight of the sample to be entered

  18. Supervision of Fed-Batch Fermentations

    DEFF Research Database (Denmark)

    Gregersen, Lars; Jørgensen, Sten Bay

    1999-01-01

    Process faults may be detected on-line using existing measurements based upon modelling that is entirely data driven. A multivariate statistical model is developed and used for fault diagnosis of an industrial fed-batch fermentation process. Data from several (25) batches are used to develop a mo...

  19. Mouse preantral follicle growth in 3D co-culture system using human menstrual blood mesenchymal stem cell.

    Science.gov (United States)

    Rajabi, Zahra; Yazdekhasti, Hossein; Noori Mugahi, Seyed Mohammad Hossein; Abbasi, Mehdi; Kazemnejad, Somaieh; Shirazi, Abolfazl; Majidi, Masoumeh; Zarnani, Amir-Hassan

    2018-03-01

    Follicle culture provides a condition which can help investigators to evaluate various aspects of ovarian follicle growth and development and impact of different components and supplementations as well as presumably application of follicle culture approach in fertility preservation procedures. Mesenchymal Stem Cells (MSCs), particularly those isolated from menstrual blood has the potential to be used as a tool for improvement of fertility. In the current study, a 3D co-culture system with mice preantral follicles and human Menstrual Blood Mesenchymal Stem Cells (MenSCs) using either collagen or alginate beads was designed to investigate whether this system allows better preantral follicles growth and development. Results showed that MenSCs increase the indices of follicular growth including survival rate, diameter, and antrum formation as well as the rate of in vitro maturation (IVM) in both collagen and alginates beads. Although statistically not significant, alginate was found to be superior in terms of supporting survival rate and antrum formation. Hormone assay demonstrated that the amount of secreted 17 β-estradiol and progesterone in both 3D systems increased dramatically after 12 days, with the highest levels in system employing MenSCs. Data also demonstrated that relative expression of studied genes increased for Bmp15 and Gdf9 and decreased for Mater when follicles were cultured in the presence of MenSCs. Collectively, results of the present study showed that MenSCs could improve indices of follicular growth and maturation in vitro. Further studies are needed before a clinical application of MenSCs-induced IVM is considered. Copyright © 2018 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. All rights reserved.

  20. A comparative study on growth performance and biochemical composition of mixed culture of Isochrysis galbana and Chaetoceros calcitrans with monocultures

    Digital Repository Service at National Institute of Oceanography (India)

    Phatarpekar, P.V.; Sreepada, R.A.; Pednekar, C.; Achuthankutty, C.T.

    of commercially valuable fish and shellfish as they constitute an almost exclusive live food for the larvae. Therefore, the development of efficient production systems of microalgae of optimal nutritional quality is vital and will have spin-offs such as improved... survival and growth of the cultured animals, reduction in labour costs, etc. Among many microalgae identified for aquaculture purposes, species belonging to the genera, Chaeto- ceros and Isochrysis are extensively used as food in most shrimp hatcheries...

  1. Misinterpretation of Gram Stain from the Stationary Growth Phase of Positive Blood Cultures forBrucellaandAcinetobacterSpecies.

    Science.gov (United States)

    Bazzi, Ali M; Al-Tawfiq, Jaffar A; Rabaan, Ali A

    2017-01-01

    Acinetobacter baumannii and Brucella species are Gram-negative organisms that are vulnerable to misinterpretation as Gram-positive or Gram-variable in blood cultures. We assess the random errors in gram stain interpretation to reduce the likelihood of such errors and therefore patient harm. Aerobic and anaerobic blood cultures from two patients in an acute care facility in Saudi Arabia were subjected to preliminary Gram-staining. In case 1, VITEK-2 Anaerobe Identification, repeat Gram staining from a blood agar plate, Remel BactiDrop™ Oxidase test, Urea Agar urease test and real-time PCR were used to confirm presence of Brucella and absence of Coryneform species. In case 2, repeat Gram- staining from the plate and the vials, VITEK-2 Gram-Negative Identification, real-time PCR and subculture on to Columbia agar, blood agar, and MacConkey agar were carried out to identify A. baumannii . In case 1, initially pleomorphic Gram-positive bacteria were identified. Coryneform species were suspected. Tiny growth was observed after 24 h on blood agar plates, and good growth by 48 h. Presence of Brucella species was ultimately confirmed. In case 2, preliminary Gram-stain results suggested giant Gram-positive oval cocci. Further testing over 18-24 h identified A. baumannii . Oxidase test from the plate and urease test from the culture vial is recommended after apparent identification of pleomorphic Gram-positive bacilli from blood culture, once tiny growth is observed, to distinguish Brucella from Corynebacterium species. If giant Gram-positive oval cocci are indicated by preliminary Gram-staining, it is recommended that the Gram stain be repeated from the plate after 4-6 h, or culture should be tested in Triple Sugar Iron (TSI) medium and the Gram stain repeated after 2-4 h incubation.

  2. A method of batch-purifying microalgae with multiple antibiotics at extremely high concentrations

    Science.gov (United States)

    Han, Jichang; Wang, Song; Zhang, Lin; Yang, Guanpin; Zhao, Lu; Pan, Kehou

    2016-01-01

    Axenic microalgal strains are highly valued in diverse microalgal studies and applications. Antibiotics, alone or in combination, are often used to avoid bacterial contamination during microalgal isolation and culture. In our preliminary trials, we found that many microalgae ceased growing in antibiotics at extremely high concentrations but could resume growth quickly when returned to an antibiotics-free liquid medium and formed colonies when spread on a solid medium. We developed a simple and highly efficient method of obtaining axenic microalgal cultures based on this observation. First, microalgal strains of different species or strains were treated with a mixture of ampicillin, gentamycin sulfate, kanamycin, neomycin and streptomycin (each at a concentration of 600 mg/L) for 3 days; they were then transferred to antibiotics-free medium for 5 days; and finally they were spread on solid f/2 media to allow algal colonies to form. With this method, five strains of Nannochloropsis sp. (Eustigmatophyceae), two strains of Cylindrotheca sp. (Bacillariophyceae), two strains of Tetraselmis sp. (Chlorodendrophyceae) and one strain of Amphikrikos sp. (Trebouxiophyceae) were purified successfully. The method shows promise for batch-purifying microalgal cultures.

  3. [Effect of vanadium compounds on the growth and production of coumarins in the suspension culture of Angelica archangelica L].

    Science.gov (United States)

    Siatka, T; Kasparová, M

    2007-10-01

    Plant tissue cultures represent a promising source of substances of natural origin. The main problem of their use is a low production of the majority of secondary metabolites. One of the methods of increasing the production of these substances is elicitation, because the biosynthesis of many secondary metabolites in plant cells is part of the defensive reaction against biological or abiotic stress influences. The paper tested vanadium compounds as potential elicitors of the production of coumarins: sodium vanadate (0.2; 1; 10; 100 and 1000 microM/l of medium) and vanadyl sulfate (10; 20; 50; 100; 200 and 500 microM/l of medium). The toxicity of these substances for the culture was simultaneously monitored by means of the evaluation of the effects on growth (characterized by fresh and dry weights of biomass at the end of two-week cultivation). The cultures were grown both in the light and dark. The growth of the cultures was not influenced by sodium vanadate at concentrations of 0.2 to 100 microM. A vanadate concentration of 1000 microM acted already toxically (in comparison with the control culture, the fresh weight was decreased by 28 % and the dry weight by 41% when cultivated in the light; the fresh weight by 69% and the dry weight by 66% when cultivated in the dark). Vanadyl sulfate in concentrations of 10 to 50 microM did not affect the growth of the culture, at higher concentrations it decreased it gradually: a concentration of 500 microM acted already toxically, again more markedly when cultivated in the light (in comparison with the control culture, the fresh weight was decreased by 27% and dry weight by 38% when cultivated in the light; the fresh weight by 65% and the dry weight by 61% when cultivated in the dark). The production of coumarins was stimulated by sodium vanadate in a concentration of 0.2 and 1 microM when cultivated in the light. The content of coumarins increased in comparison with the control culture mainly in the medium by 46% and by 25

  4. Feeding strategies for the improved biosynthesis of canthaxanthin from enzymatic hydrolyzed molasses in the fed-batch fermentation of Dietzia natronolimnaea HS-1.

    Science.gov (United States)

    Gharibzahedi, Seyed Mohammad Taghi; Razavi, Seyed Hadi; Mousavi, Mohammad

    2014-02-01

    The effect of two enzymatic hydrolyzed molasses (EHM)-feeding strategies including constant-(CFR) and exponential-(EFR) feeding rate on canthaxanthin (CTX) biosynthesis by Dietzia natronolimnaea HS-1 fed-batch fermentation was studied. The results showed that the CFR of 7 ml/h with an EHM content of 45 g/l led to the highest values of specific growth rate (0.127 h(-1)), biomass dry weight (17.66 g/l), total carotenoid (16.31 mg/l) and CTX (14.67 mg/l). A significant decrease in the kinetic growth and production parameters by the increasing EHM concentration from 30 to 60 g/l during EFR fed-batch bioprocess was observed (p<0.01). This study concluded that EHM alone can displace glucose-based medium towards improved CTX biosynthesis from D. natronolimnaea HS-1 using a CFR strategy during fed-batch culture. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. A candidate gene association study for growth performance in an improved giant freshwater prawn (Macrobrachium rosenbergii ) culture line.

    Science.gov (United States)

    Jung, Hyungtaek; Lyons, Russell E; Li, Yutao; Thanh, Nguyen Minh; Dinh, Hung; Hurwood, David A; Salin, Krishna R; Mather, Peter B

    2014-04-01

    A candidate gene approach using type I single nucleotide polymorphism (SNP) markers can provide an effective method for detecting genes and gene regions that underlie phenotypic variation in adaptively significant traits. In the absence of available genomic data resources, transcriptomes were recently generated in Macrobrachium rosenbergii to identify candidate genes and markers potentially associated with growth. The characterisation of 47 candidate loci by ABI re-sequencing of four cultured and eight wild samples revealed 342 putative SNPs. Among these, 28 SNPs were selected in 23 growth-related candidate genes to genotype in 200 animals selected for improved growth performance in an experimental GFP culture line in Vietnam. The associations between SNP markers and individual growth performance were then examined. For additive and dominant effects, a total of three exonic SNPs in glycogen phosphorylase (additive), heat shock protein 90 (additive and dominant) and peroxidasin (additive), and a total of six intronic SNPs in ankyrin repeats-like protein (additive and dominant), rolling pebbles (dominant), transforming growth factor-β induced precursor (dominant), and UTP-glucose-1-phosphate uridylyltransferase 2 (dominant) genes showed significant associations with the estimated breeding values in the experimental animals (P =0.001-0.031). Individually, they explained 2.6-4.8 % of the genetic variance (R²=0.026-0.048). This is the first large set of SNP markers reported for M. rosenbergii and will be useful for confirmation of associations in other samples or culture lines as well as having applications in marker-assisted selection in future breeding programs.

  6. Cultural

    Science.gov (United States)

    Wilbur F. LaPage

    1971-01-01

    A critical look at outdoor recreation research and some underlying premises. The author focuses on the concept of culture as communication and how it influences our perception of problems and our search for solutions. Both outdoor recreation and science are viewed as subcultures that have their own bodies of mythology, making recreation problems more difficult to...

  7. Effect of sucrose concentration and gamma irradiation on growth and essential oil composition of spearmint plant through tissue culture

    International Nuclear Information System (INIS)

    El-Sharnouby, M.E.

    2007-01-01

    In vitro culture of spearmint plant (Mentha spicata L) using different sucrose concentrations and different gamma irradiation treatments was investigated. The shoot tips of spearmint plant were cultured on MS medium without hormones and supplemented with different concentrations of sucrose (10, 20, 30 and 40 g/l) then exposed to different gamma irradiation treatments (2,4,6 and 8 Krad) to determine their effects on growth and chemical composition in different sub-culturing media . The data showed that culturing shoots of Mentha spicata on MS medium containing 10 g/l sucrose produced the highest values of callus than other treatments and the maximum number of shoots was produced on MS medium supplemented with 20 g/l sucrose. Irradiation of spearmint shoots at 8 Krad when cultured on MS medium containing 30 or 40 g/l sucrose caused minimum number of shoots, whereas the longest shoots were produced with MS medium containing 20 g/l sucrose after irradiation at 60 Gy gamma dose. Treating shoots of Mentha spicata by gamma irradiation at 8 Krad and culturing on MS medium containing 30 g/l sucrose produced all sub-cultures in shortest length of shoots. Moreover, adding 40 g/l of sucrose in MS medium gave the highest number of leaves than other treatments. Exposing shoots of spearmint plant to gamma irradiation at 8 Krad decreased the number of leaves when culturing on MS medium containing 10 or 30 g/l sucrose. Furthermore, the selected samples showed many differences on spearmint oil composition and proline content regarding sucrose levels and gamma irradiation doses

  8. Diet influences growth rates and allergen and endotoxin contents of cultured Dermatophagoides farinae and Dermatophagoides pteronyssinus house dust mites.

    Science.gov (United States)

    Avula-Poola, Swetha; Morgan, Marjorie S; Arlian, Larry G

    2012-01-01

    The house dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus are cultured to obtain material for the production of allergen extracts for research, diagnostic and immunotherapeutic purposes. We cultured mites on two different diets that supported thriving populations and determined the population growth rates, dynamics of allergen accumulation, and endotoxin concentrations in extracts made from mites harvested from the cultures. D. farinae populations grew faster on a diet of rodent chow/yeast than on an egg/yeast diet but a larger peak population size was achieved on the egg/yeast diet. Diet influenced the dynamics of the production of groups 1 and 2 allergens and the group 1/2 ratios for both species. To population peak, Der f 1 was produced at a faster rate on the chow/yeast diet but greater amounts of Der f 1 were produced by mites grown on the egg/yeast diet. D. pteronyssinus populations grew faster and achieved greater density on the egg/yeast diet compared to the chow/yeast diet. D. pteronyssinus produced more Der p 1 than Der p 2 when grown on chow/yeast while more Der p 2 than Der p 1 was produced on egg/yeast. Endotoxin concentrations in extracts made from whole cultures for both species at maximum population density were very different in the two diets. Washing the mites resulted in the loss of up to 88% of the allergen. Mite-culturing diet directly effects population growth, the dynamics of allergen accumulation, the group 1/2 allergen ratio and the endotoxin contents in extracts of cultured house dust mites. Copyright © 2012 S. Karger AG, Basel.

  9. Effects of extracellular matrix proteins on macrophage differentiation, growth, and function: comparison of liquid and agar culture systems

    Science.gov (United States)

    Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Both spaceflight and skeletal unloading suppress the haematopoietic differentiation of macrophages (Sonnenfeld et al., Aviat. Space Environ. Med., 61:648-653, 1990; Armstrong et al., J. Appl. Physiol., 75:2734-2739, 1993). The mechanism behind this reduction in haematopoiesis has yet to be elucidated. However, changes in bone marrow extracellular matrix (ECM) may be involved. To further understand the role of ECM products in macrophage differentiation, we have performed experiments evaluating the effects of fibronectin, laminin, collagen type I, and collagen type IV on macrophage development and function. Bone marrow-derived macrophages cultured on four different ECM substrates in liquid culture medium showed less growth than those cultured on plastic. Significant morphological differences were seen on each of the substrates used. Phenotypically and functionally, as measured by class II major histocompatibility molecule (MHCII) expression, MAC-2 expression, and the secretion of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), these macrophages were similar. In contrast, bone marrow-derived macrophages cultured in suspension, using agar, showed no difference in growth when exposed to ECM proteins. However, IL-6 and TNF-alpha secretion was affected by fibronectin, laminin, collagen type I, and collagen type IV in a concentration-dependent manner. We conclude that the ECM products fibronectin, laminin, collagen type I, and collagen type IV have profound effects on macrophage development and function. Additionally, we suggest that an ECM-supplemented agar culture system provides an environment more analogous to in vivo bone marrow than does a traditional liquid culture system.

  10. Food additives reduce lactic acid bacterial growth in culture medium and in meat products, increasing product shelf life

    Directory of Open Access Journals (Sweden)

    Cleonice Mendes Pereira Sarmento

    2015-12-01

    Full Text Available The uncontrolled growth of lactic acid bacteria (LAB in meat and meat products leads to product spoilage, and thus shortens product shelf life. Although food additives are known to decrease LAB growth, this effect has not been analyzed in detail. Here, a detailed analysis was performed of the effects of sodium chloride, sodium polyphosphate, sodium lactate, sodium nitrite/nitrate, and garlic on the growth of the Lactobacillus plantarum in culture medium. The results were used to design and test experimental formulations of meat products. Initially, the effect of food additives on L. plantarum was evaluated using a Fractional Factorial Design (FFD, followed by a Central Composite Rotatable Design (CCRD. The Modified Gompertz Model was adjusted to the growth curves to determine the Kinetic parameters of bacterial growth (logarithmic increase in the population, specific growth rate, and lag phase extension. Higher sodium lactate and sodium chloride levels had a negative impact on L. plantarum growth parameters (p?0.05. Therefore, we designed experimental formulations of mortadella and smoked pork sausages containing 4% sodium lactate (w w-1 and 2.4-3.5% sodium chloride (w w-1, and determined LAB growth from samples of stored products produced according to these formulations, in order to determine product shelf life. There was an increased lag phase of LAB growth for most experimental formulations. Also, the experimental smoked pork sausages had a longer shelf life, which was increased by at least 22 days, suggesting that the proposed formulation, with higher than standard lactate concentration, increased the product’s shelf life.

  11. In vitro propagation of plant virus using different forms of plant tissue culture and modes of culture operation.

    Science.gov (United States)

    Shih, Sharon M-H; Doran, Pauline M

    2009-09-10

    Plant virus accumulation was investigated in vitro using three different forms of plant tissue culture. Suspended cells, hairy roots and shooty teratomas of Nicotiana benthamiana were infected with tobacco mosaic virus (TMV) using the same initial virus:biomass ratio. Viral infection did not affect tissue growth or morphology in any of the three culture systems. Average maximum virus concentrations in hairy roots and shooty teratomas were similar and about an order of magnitude higher than in suspended cells. Hairy roots were considered the preferred host because of their morphological stability in liquid medium and relative ease of culture. The average maximum virus concentration in the hairy roots was 0.82+/-0.14 mg g(-1) dry weight; viral coat protein represented a maximum of approximately 6% of total soluble protein in the biomass. Virus accumulation in hairy roots was investigated further using different modes of semi-continuous culture operation aimed at prolonging the root growth phase and providing nutrient supplementation; however, virus concentrations in the roots were not enhanced compared with simple batch culture. The relative infectivity of virus in the biomass declined by 80-90% during all the cultures tested, irrespective of the form of plant tissue used or mode of culture operation. Hairy root cultures inoculated with a transgenic TMV-based vector in batch culture accumulated green fluorescent protein (GFP); however, maximum GFP concentrations in the biomass were relatively low at 39 microg g(-1) dry weight, probably due to genetic instability of the vector. This work highlights the advantages of using hairy roots for in vitro propagation of TMV compared with shooty teratomas and suspended plant cells, and demonstrates that batch root culture is more effective than semi-continuous operations for accumulation of high virus concentrations in the biomass.

  12. Cellular responses of Saccharomyces cerevisiae at near-zero growth rates: transcriptome analysis of anaerobic retentostat cultures.

    Science.gov (United States)

    Boender, Léonie G M; van Maris, Antonius J A; de Hulster, Erik A F; Almering, Marinka J H; van der Klei, Ida J; Veenhuis, Marten; de Winde, Johannes H; Pronk, Jack T; Daran-Lapujade, Pascale

    2011-12-01

    Extremely low specific growth rates (below 0.01 h(-1) ) represent a largely unexplored area of microbial physiology. In this study, anaerobic, glucose-limited retentostats were used to analyse physiological and genome-wide transcriptional responses of Saccharomyces cerevisiae to cultivation at near-zero specific growth rates. While quiescence is typically investigated as a result of carbon starvation, cells in retentostat are fed by small, but continuous carbon and energy supply. Yeast cells cultivated near-zero specific growth rates, while metabolically active, exhibited characteristics previously associated with quiescence, including accumulation of storage polymers and an increased expression of genes involved in exit from the cell cycle into G(0) . Unexpectedly, analysis of transcriptome data from retentostat and chemostat cultures showed, as specific growth rate was decreased, that quiescence-related transcriptional responses were already set in at specific growth rates above 0.025 h(-1) . These observations stress the need for systematic dissection of physiological responses to slow growth, quiescence, ageing and starvation and indicate that controlled cultivation systems such as retentostats can contribute to this goal. Furthermore, cells in retentostat do not (or hardly) divide while remaining metabolically active, which emulates the physiological status of metazoan post-mitotic cells. We propose retentostat as a powerful cultivation tool to investigate chronological ageing-related processes. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  13. What the growth of a space tourism industry could contribute to employment, economic growth, environmental protection, education, culture and world peace

    Science.gov (United States)

    Collins, Patrick; Autino, Adriano

    2010-06-01

    The authors argue that the creation of a popular new industry of passenger space travel could be economically and socially very beneficial in creating new employment in aerospace and related fields in order to supply these services. In doing so, the application of nearly a half-century of technological development that has yet to be used commercially could create many new aerospace engineering business opportunities. In addition, by growing to large scale, space tourism has unique potential to reduce the cost of space travel sharply, thereby making many other activities in space feasible and profitable. The paper discusses the scope for new employment, stimulating economic growth, reducing environmental damage, sustaining education particularly in the sciences, stimulating cultural growth, and preserving peace by eliminating any need for "resource wars".

  14. Growth of Trichomycterus punctulatus “Life” in three population densities in intensive culture system with recirculation

    Directory of Open Access Journals (Sweden)

    Segundo Juan López Cubas

    2013-09-01

    Full Text Available The present research was conducted in order to determine the effect of population density on the growth of Trichomycterus punctulatus, in an intensive culture system with recirculation, to which was applied Increasing Stimulus Experimental Design with three treatments without repetition: 2.21 lifes / liter, 2.94 lifes / liter and 3.68 lifes / liter. The fish were fed a diet of 32% protein and were sampled monthly growth as well as physical and chemical parameters of the water. We applied ANOVA and Duncan test. Growth of T. punctulatus was affected by population density in direct, with a higher density of 3.68 lifes / liter: 90.90 mm and 5.95 g; also the overall production per cubic meter and observed the same trend. The physicochemical parameters of the water were similar among treatments and were within the ranges of good development for fish.

  15. Uneven batch data alignment with application to the control of batch end-product quality.

    Science.gov (United States)

    Wan, Jian; Marjanovic, Ognjen; Lennox, Barry

    2014-03-01

    Batch processes are commonly characterized by uneven trajectories due to the existence of batch-to-batch variations. The batch end-product quality is usually measured at the end of these uneven trajectories. It is necessary to align the time differences for both the measured trajectories and the batch end-product quality in order to implement statistical process monitoring and control schemes. Apart from synchronizing trajectories with variable lengths using an indicator variable or dynamic time warping, this paper proposes a novel approach to align uneven batch data by identifying short-window PCA&PLS models at first and then applying these identified models to extend shorter trajectories and predict future batch end-product quality. Furthermore, uneven batch data can also be aligned to be a specified batch length using moving window estimation. The proposed approach and its application to the control of batch end-product quality are demonstrated with a simulated example of fed-batch fermentation for penicillin production. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Algal Feedback and Removal Efficiency in a Sequencing Batch Reactor Algae Process (SBAR to Treat the Antibiotic Cefradine.

    Directory of Open Access Journals (Sweden)

    Jianqiu Chen

    Full Text Available Many previous studies focused on the removal capability for contaminants when the algae grown in an unexposed, unpolluted environment and ignored whether the feedback of algae to the toxic stress influenced the removal capability in a subsequent treatment batch. The present research investigated and compared algal feedback and removal efficiency in a sequencing batch reactor algae process (SBAR to remove cefradine. Three varied pollution load conditions (10, 30 and 60 mg/L were considered. Compared with the algal characteristics in the first treatment batch at 10 and 30 mg/L, higher algal growth inhibition rates were observed in the second treatment batch (11.23% to 20.81%. In contrast, algae produced more photosynthetic pigments in response to cefradine in the second treatment batch. A better removal efficiency (76.02% was obtained during 96 h when the alga treated the antibiotic at 60 mg/L in the first treatment batch and at 30 mg/L in the second treatment batch. Additionally, the removal rate per unit algal density was also improved when the alga treated the antibiotic at 30 or 60 mg/L in the first treatment batch, respectively and at 30 mg/L in the second treatment batch. Our result indicated that the green algae were also able to adapt to varied pollution loads in different treatment batches.

  17. Algal Feedback and Removal Efficiency in a Sequencing Batch Reactor Algae Process (SBAR) to Treat the Antibiotic Cefradine

    Science.gov (United States)

    Chen, Jianqiu; Zheng, Fengzhu; Guo, Ruixin

    2015-01-01

    Many previous studies focused on the removal capability for contaminants when the algae grown in an unexposed, unpolluted environment and ignored whether the feedback of algae to the toxic stress influenced the removal capability in a subsequent treatment batch. The present research investigated and compared algal feedback and removal efficiency in a sequencing batch reactor algae process (SBAR) to remove cefradine. Three varied pollution load conditions (10, 30 and 60 mg/L) were considered. Compared with the algal characteristics in the first treatment batch at 10 and 30 mg/L, higher algal growth inhibition rates were observed in the second treatment batch (11.23% to 20.81%). In contrast, algae produced more photosynthetic pigments in response to cefradine in the second treatment batch. A better removal efficiency (76.02%) was obtained during 96 h when the alga treated the antibiotic at 60 mg/L in the first treatment batch and at 30 mg/L in the second treatment batch. Additionally, the removal rate per unit algal density was also improved when the alga treated the antibiotic at 30 or 60 mg/L in the first treatment batch, respectively and at 30 mg/L in the second treatment batch. Our result indicated that the green algae were also able to adapt to varied pollution loads in different treatment batches. PMID:26177093

  18. Effects of Natural Bioactive Products on the Growth and Ginsenoside Contents of Panax ginseng Cultured in an Aeroponic System

    Science.gov (United States)

    Kim, Geum-Soog; Lee, Seung-Eun; Noh, Hyung-Jun; Kwon, Hyuck; Lee, Sung-Woo; Kim, Seung-Yu; Kim, Yong-Bum

    2012-01-01

    This study was conducted to evaluate th