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Sample records for coelicolor fed-batch cultivations

  1. Sensor combination and chemometric variable selection for online monitoring of Streptomyces coelicolor fed-batch cultivations

    DEFF Research Database (Denmark)

    Ödman, Peter; Johansen, C.L.; Olsson, L.

    2010-01-01

    of biomass and substrate (casamino acids) concentrations, respectively. The effect of combination of fluorescence and gas analyzer data as well as of different variable selection methods was investigated. Improved prediction models were obtained by combination of data from the two sensors and by variable......Fed-batch cultivations of Streptomyces coelicolor, producing the antibiotic actinorhodin, were monitored online by multiwavelength fluorescence spectroscopy and off-gas analysis. Partial least squares (PLS), locally weighted regression, and multilinear PLS (N-PLS) models were built for prediction...

  2. Combined age and segregated kinetic model for industrial-scale penicillin fed-batch cultivation

    NARCIS (Netherlands)

    Wang, Z.F.; Lauwerijssen, M.J.C.; Yuan, J.Q.

    2005-01-01

    This paper proposes a cell age model forPenicillium chrysogenum fed-batch cultivation to supply a qualitative insight into morphology-associated dynamics. The average ages of the segregated cell populations, such as growing cells, non-growing cells and intact productive cells, were estimated by this

  3. Preferences based Control Design of Complex Fed-batch Cultivation Process

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    Yuri Pavlov

    2009-08-01

    Full Text Available In the paper is presented preferences based control design and stabilization of the growth rate of fed-batch cultivation processes. The control is based on an enlarged Wang-Monod-Yerusalimsky kinetic model. Expected utility theory is one of the approaches for utilization of conceptual information (expert preferences. In the article is discussed utilization of stochastic machine learning procedures for evaluation of expert utilities as criteria for optimization.

  4. Change in hyphal morphology of Aspergillus Oryzae during fed-batch cultivation

    DEFF Research Database (Denmark)

    Haack, Martin Brian; Olsson, Lisbeth; Hansen, K

    2006-01-01

    the batch phase from 2.8-2.9 up to 4.0-4.4 mu m. The diameter of the hyphal elements remained constant, around 4 mu m, after the feed was started. However, the diameter of the immediate hyphal tip, where the enzyme secretion is thought to take place, increased dramatically with up to a factor 2.5 during......Industrial enzymes are often produced by filamentous fungi in fed-batch cultivations. During cultivation, the different morphological forms displayed by the fungi have an impact on the overall production. The morphology of a recombinant lipase producing Aspergillus oryzae strain was investigated...

  5. Modelling of Functional States during Saccharomyces cerevisiae Fed-batch Cultivation

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    Stoyan Tzonkov

    2005-04-01

    Full Text Available An implementation of functional state approach for modelling of yeast fed-batch cultivation is presented in this paper. Using of functional state modelling approach aims to overcome the main disadvantage of using global process model, namely complex model structure and big number of model parameters, which complicate the model simulation and parameter estimation. This approach has computational advantages, such as the possibility to use the estimated values from the previous state as starting values for estimation of parameters of a new state. The functional state modelling approach is applied here for fedbatch cultivation of Saccharomyces cerevisiae. Four functional states are recognised and parameter estimation of local models is presented as well.

  6. 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...

  7. Online optimal experimental re-design in robotic parallel fed-batch cultivation facilities.

    Science.gov (United States)

    Cruz Bournazou, M N; Barz, T; Nickel, D B; Lopez Cárdenas, D C; Glauche, F; Knepper, A; Neubauer, P

    2017-03-01

    We present an integrated framework for the online optimal experimental re-design applied to parallel nonlinear dynamic processes that aims to precisely estimate the parameter set of macro kinetic growth models with minimal experimental effort. This provides a systematic solution for rapid validation of a specific model to new strains, mutants, or products. In biosciences, this is especially important as model identification is a long and laborious process which is continuing to limit the use of mathematical modeling in this field. The strength of this approach is demonstrated by fitting a macro-kinetic differential equation model for Escherichia coli fed-batch processes after 6 h of cultivation. The system includes two fully-automated liquid handling robots; one containing eight mini-bioreactors and another used for automated at-line analyses, which allows for the immediate use of the available data in the modeling environment. As a result, the experiment can be continually re-designed while the cultivations are running using the information generated by periodical parameter estimations. The advantages of an online re-computation of the optimal experiment are proven by a 50-fold lower average coefficient of variation on the parameter estimates compared to the sequential method (4.83% instead of 235.86%). The success obtained in such a complex system is a further step towards a more efficient computer aided bioprocess development. Biotechnol. Bioeng. 2017;114: 610-619. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Construction and fed-batch cultivation of Candida famata with enhanced riboflavin production.

    Science.gov (United States)

    Dmytruk, Kostyantyn; Lyzak, Oleksy; Yatsyshyn, Valentyna; Kluz, Maciej; Sibirny, Vladimir; Puchalski, Czeslaw; Sibirny, Andriy

    2014-02-20

    Riboflavin (vitamin B2) is an essential nutrition component serving as a precursor of coenzymes FMN and FAD that are involved mostly in reactions of oxidative metabolism. Riboflavin is produced in commercial scale and is used in feed and food industries, and in medicine. The yeast Candida famata (Candida flareri) belongs to the group of so called "flavinogenic yeasts" which overproduce riboflavin under iron limitation. Three genes SEF1, RIB1 and RIB7 coding for a putative transcription factor, GTP cyclohydrolase II and riboflavin synthase, respectively were simultaneously overexpressed in the background of a non-reverting riboflavin producing mutant AF-4, obtained earlier in our laboratory using methods of classical selection (Dmytruk et al. (2011), Metabolic Engineering 13, 82-88). Cultivation conditions of the constructed strain were optimized for shake-flasks and bioreactor cultivations. The constructed strain accumulated up to 16.4g/L of riboflavin in optimized medium in a 7L laboratory bioreactor during fed-batch fermentation. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. 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.

  10. 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

  11. Citric acid production from hydrolysate of pretreated straw cellulose by Yarrowia lipolytica SWJ-1b using batch and fed-batch cultivation.

    Science.gov (United States)

    Liu, Xiaoyan; Lv, Jinshun; Zhang, Tong; Deng, Yuanfang

    2015-01-01

    In this study, crude cellulase produced by Trichoderma reesei Rut-30 was used to hydrolyze pretreated straw. After the compositions of the hydrolysate of pretreated straw were optimized, the study showed that natural components of pretreated straw without addition of any other components such as (NH4)2SO4, KH2PO4, or Mg(2+) were suitable for citric acid production by Yarrowia lipolytica SWJ-1b, and the optimal ventilatory capacity was 10.0 L/min/L medium. Batch and fed-batch production of citric acid from the hydrolysate of pretreated straw by Yarrowia lipolytica SWJ-1b has been investigated. In the batch cultivation, 25.4 g/L and 26.7 g/L citric acid were yields from glucose and hydrolysate of straw cellulose, respectively, while the cultivation time was 120 hr. In the three-cycle fed-batch cultivation, citric acid (CA) production was increased to 42.4 g/L and the cultivation time was extended to 240 hr. However, iso-citric acid (ICA) yield in fed-batch cultivation (4.0 g/L) was similar to that during the batch cultivation (3.9 g/L), and only 1.6 g/L of reducing sugar was left in the medium at the end of fed-batch cultivation, suggesting that most of the added carbon was used in the cultivation.

  12. De novo biosynthesis of biodiesel by Escherichia coli in optimized fed-batch cultivation.

    Directory of Open Access Journals (Sweden)

    Yangkai Duan

    Full Text Available Biodiesel is a renewable alternative to petroleum diesel fuel that can contribute to carbon dioxide emission reduction and energy supply. Biodiesel is composed of fatty acid alkyl esters, including fatty acid methyl esters (FAMEs and fatty acid ethyl esters (FAEEs, and is currently produced through the transesterification reaction of methanol (or ethanol and triacylglycerols (TAGs. TAGs are mainly obtained from oilseed plants and microalgae. A sustainable supply of TAGs is a major bottleneck for current biodiesel production. Here we report the de novo biosynthesis of FAEEs from glucose, which can be derived from lignocellulosic biomass, in genetically engineered Escherichia coli by introduction of the ethanol-producing pathway from Zymomonas mobilis, genetic manipulation to increase the pool of fatty acyl-CoA, and heterologous expression of acyl-coenzyme A: diacylglycerol acyltransferase from Acinetobacter baylyi. An optimized fed-batch microbial fermentation of the modified E. coli strain yielded a titer of 922 mg L(-1 FAEEs that consisted primarily of ethyl palmitate, -oleate, -myristate and -palmitoleate.

  13. Thermodynamics of metabolic pathways for penicillin production: Analysis of thermodynamic feasibility and free energy changes during fed-batch cultivation

    DEFF Research Database (Denmark)

    Pissarra, P.D.; Nielsen, Jens Bredal

    1997-01-01

    This paper describes the thermodynamic analysis of pathways related to penicillin production in Penicillium chrysogenum. First a thermodynamic feasibility analysis is performed of the L-lysine pathway of which one of the precursors for penicillin biosynthesis (alpha-aminoadipic acid......) is an intermediate. It is found that the L-lysine pathway in P. chrysogenum is thermodynamically feasible and that the calculated standard Gibbs free energy values of the two enzymes controlling the pathway flux indicate that they operate far from equilibrium. It is therefore proposed that the regulation of alpha......-aminoadipate reductase by lysine is important to maintain a high concentration of alpha-aminoadipate in order to direct the carbon flux to penicillin production. Secondly the changes in Gibbs free energy in the penicillin biosynthetic pathway during fed-batch cultivation were studied. The analysis showed that all...

  14. Development of a mathematical model for the growth associated Polyhydroxybutyrate fermentation by Azohydromonas australica and its use for the design of fed-batch cultivation strategies.

    Science.gov (United States)

    Gahlawat, Geeta; Srivastava, Ashok K

    2013-06-01

    In the present investigation, batch cultivation of Azohydromonas australica DSM 1124 was carried out in a bioreactor for growth associated PHB production. The observed batch PHB production kinetics data was then used for the development of a mathematical model which adequately described the substrate limitation and inhibition during the cultivation. The statistical validity test demonstrated that the proposed mathematical model predictions were significant at 99% confidence level. The model was thereafter extrapolated to fed-batch to identify various nutrients feeding regimes during the bioreactor cultivation to improve the PHB accumulation. The distinct capability of the mathematical model to predict highly dynamic fed-batch cultivation strategies was demonstrated by experimental implementation of two fed-batch cultivation strategies. A significantly high PHB concentration of 22.65 g/L & an overall PHB content of 76% was achieved during constant feed rate fed-batch cultivation which is the highest PHB content reported so far using A. australica. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Expression of recombinant Pseudomonas stutzeri di-heme cytochrome c(4) by high-cell-density fed-batch cultivation of Pseudomonas putida

    DEFF Research Database (Denmark)

    Thuesen, Marianne Hallberg; Nørgaard, Allan; Hansen, Anne Merete

    2003-01-01

    The gene of the di-heme protein cytochrome c(4) from Pseudomonas stutzeri was expressed in Pseudomonas putida. High-yield expression of the protein was achieved by high-cell-density fed-batch cultivation using an exponential glucose feeding strategy. The recombinant cytochrome c(4) protein...

  16. ENHANCED PRODUCTION OF POLYHYDROXYBUTYRATE (PHB FROM AGRO-INDUSTRIAL WASTES; FED-BATCH CULTIVATION AND STATISTICAL MEDIA OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Mahmoud M. Berekaa

    2016-06-01

    Full Text Available Bacillus megaterium SW1-2 showed enhanced growth and polyhydroxybutyrate (PHB production during cultivation on date palm syrup (DEPS or sugar cane molasses. FT-IR and NMR spectroscopic analyses of the polymer accumulated during growth on DEPS revealed specific absorption peaks characteristic for PHB. 1.65 g/L of PHB (56.9% CDW was produced during growth on medium supplemented with 2 g/L of DEPS. Approximately, 36.1% CDW of PHB were recorded during growth on sugar cane molasses. Six runs of different fed-batch cultivation strategies were tested, the optimal run showed approximately 6.87-fold increase. Modified E2 medium was prefered recording 10.11 and 11.34 g/L of total PHB produced for runs 1 and 2, at the end of 96 h incubation period, respectively. Decrease in PHB was recorded during growth on complex medium (run 3 and run 4. In another independent optimization strategy, ten variables were concurrently examined for their significance on PHB production by Plackett-Burman statistical design for the first time. Among variables, DEPS-II and inoculum concentration followed by KH2PO4 and (NH42SO4 were found to be the most significant variables encourage PHB production. Indeed, DEPS-II or Fresh syrup is more significant than commercial syrup DEPS-I (p-value= 0.05. RPM, incubation period have highly negative effect on PHB production. Role of ago-industrial wastes, especially DEPS, in enhancement of PHB production was closely discussed.

  17. Biotransformation of sweet lime pulp waste into high-quality nanocellulose with an excellent productivity using Komagataeibacter europaeus SGP37 under static intermittent fed-batch cultivation.

    Science.gov (United States)

    Dubey, Swati; Singh, Jyoti; Singh, R P

    2018-01-01

    Herein, sweet lime pulp waste (SLPW) was utilized as a low- or no-cost feedstock for the production of bacterial nanocellulose (BNC) alone and in amalgamation with other nutritional supplements by the isolate K. europaeus SGP37 under static batch and static intermittent fed-batch cultivation. The highest yield (26.2±1.50gL -1 ) was obtained in the hot water extract of SLPW supplemented with the components of HS medium, which got further boosted to 38±0.85gL -1 as the cultivation strategy was shifted from static batch to static intermittent fed-batch. BNC obtained from various SLPW medium was similar or even superior to that obtained with standard HS medium in terms of its physicochemical properties. The production yields of BNC thus obtained are significantly higher and fit well in terms of industrial scale production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Scale-up bioprocess development for production of the antibiotic valinomycin in Escherichia coli based on consistent fed-batch cultivations.

    Science.gov (United States)

    Li, Jian; Jaitzig, Jennifer; Lu, Ping; Süssmuth, Roderich D; Neubauer, Peter

    2015-06-12

    Heterologous production of natural products in Escherichia coli has emerged as an attractive strategy to obtain molecules of interest. Although technically feasible most of them are still constrained to laboratory scale production. Therefore, it is necessary to develop reasonable scale-up strategies for bioprocesses aiming at the overproduction of targeted natural products under industrial scale conditions. To this end, we used the production of the antibiotic valinomycin in E. coli as a model system for scalable bioprocess development based on consistent fed-batch cultivations. In this work, the glucose limited fed-batch strategy based on pure mineral salt medium was used throughout all scales for valinomycin production. The optimal glucose feed rate was initially detected by the use of a biocatalytically controlled glucose release (EnBase® technology) in parallel cultivations in 24-well plates with continuous monitoring of pH and dissolved oxygen. These results were confirmed in shake flasks, where the accumulation of valinomycin was highest when the specific growth rate decreased below 0.1 h(-1). This correlation was also observed for high cell density fed-batch cultivations in a lab-scale bioreactor. The bioreactor fermentation produced valinomycin with titers of more than 2 mg L(-1) based on the feeding of a concentrated glucose solution. Valinomycin production was not affected by oscillating conditions (i.e. glucose and oxygen) in a scale-down two-compartment reactor, which could mimic similar situations in industrial bioreactors, suggesting that the process is very robust and a scaling of the process to a larger industrial scale appears a realistic scenario. Valinomycin production was scaled up from mL volumes to 10 L with consistent use of the fed-batch technology. This work presents a robust and reliable approach for scalable bioprocess development and represents an example for the consistent development of a process for a heterologously expressed natural

  19. [Optimization of cultural condition of genetic engineering strain for antibiotic peptide adenoregulin and research on its fed-batch cultivation].

    Science.gov (United States)

    Zhou, Yu-Xun; Cao, Wei; Wei, Dong-Zhi; Luo, Qing-Ping; Wang, Jin-Zhi

    2005-07-01

    33 amino acid antibiotic peptide adenoregulin (ADR), which were firstly isolated from the skin of South America arboreal frog Phyllomedusa bicolor, forms alpha-helix amphipathic structure in apolar medium and has a wide spectrum of antimicrobial activity and high potency of lytic ability. Adr gene was cloned in pET32a and transformed into Escherichia coli BL21(DE3) . The cultural and inductive conditions of E. coli BL21(DE3)/pET32a-adr have been optimized. The effect of three factors which were time point of induction, concentration of IPTG in the culture and time of induction on the expression level of Trx-ADR was investigated. The results indicated that the expression level was affected by the time point of induction most predominantly. 9 veriaties of media in which BL21 (DE3)/pET32a-adr was cultured and induced were tested to achieve high expression level of target protein. It was found that glucose in the medium played an important role in keeping stable and high expression level of Trx-ADR. The optimal inductive condition is as follows: the culture medium is 2 x YT + 0.5% glucose, the time point of induction is OD600 = 0.9, the final concentration of IPTG in the culture is 0.1 mmol/L and the induction time is 4 h. BL21 (DE3)/pET32a-adr was cultivated according to the strategy of constant pH at early stage and exponential feeding at later stage to obtain high cell density. During the entire fed-batch phase, by controlling the feeding of glucose, the specific growth rate of the culture was controlled at about 0.15 h(-1), the accumulation of acetic acid was controlled at low level (<2 g/L), but the plasmid stability could not be maintained well. At the end of the cultivation, 40% of the bacteria in the culture lost their plasmids. As a result, the expression level of the target protein declined dramatically, but 90% of Trx-ADR was in soluble form. The expressed fusion protein showed no antibacterial activity, while the native form of ADR lysed from Trx-ADR showed

  20. Kinetic studies on batch cultivation of Trichoderma reesei and application to enhance cellulase production by fed-batch fermentation.

    Science.gov (United States)

    Ma, Lijuan; Li, Chen; Yang, Zhenhua; Jia, Wendi; Zhang, Dongyuan; Chen, Shulin

    2013-07-20

    Reducing the production cost of cellulase as the key enzyme for cellulose hydrolysis to fermentable sugars remains a major challenge for biofuel production. Because of the complexity of cellulase production, kinetic modeling and mass balance calculation can be used as effective tools for process design and optimization. In this study, kinetic models for cell growth, substrate consumption and cellulase production in batch fermentation were developed, and then applied in fed-batch fermentation to enhance cellulase production. Inhibition effect of substrate was considered and a modified Luedeking-Piret model was developed for cellulase production and substrate consumption according to the growth characteristics of Trichoderma reesei. The model predictions fit well with the experimental data. Simulation results showed that higher initial substrate concentration led to decrease of cellulase production rate. Mass balance and kinetic simulation results were applied to determine the feeding strategy. Cellulase production and its corresponding productivity increased by 82.13% after employing the proper feeding strategy in fed-batch fermentation. This method combining mathematics and chemometrics by kinetic modeling and mass balance can not only improve cellulase fermentation process, but also help to better understand the cellulase fermentation process. The model development can also provide insight to other similar fermentation processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Production of the potential sweetener 5-ketofructose from fructose in fed-batch cultivation with Gluconobacter oxydans.

    Science.gov (United States)

    Herweg, Elena; Schöpping, Marie; Rohr, Katja; Siemen, Anna; Frank, Oliver; Hofmann, Thomas; Deppenmeier, Uwe; Büchs, Jochen

    2018-07-01

    Sweeteners improve the dietary properties of many foods. A candidate for a new natural sweetener is 5-ketofructose. In this study a fed-batch process for the production of 5-ketofructose was developed. A Gluconobacter oxydans strain overexpressing a fructose dehydrogenase from G. japonicus was used and the sensory properties of 5-ketofructose were analyzed. The compound showed an identical sweet taste quality as fructose and a similar intrinsic sweet threshold concentration of 16.4 mmol/L. The production of 5-ketofructose was characterized online by monitoring of the respiration activity in shake flasks. Pulsed and continuous fructose feeding was realized in 2 L stirred tank reactors and maximum fructose consumption rates were determined. 5-Ketofructose concentrations of up to 489 g/L, product yields up to 0.98 g 5-KF /g fructose and space time yields up to 8.2 g/L/h were reached highlighting the potential of the presented process. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. 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.

  3. HPLC-ESI-MS(n) Analysis, Fed-Batch Cultivation Enhances Bioactive Compound Biosynthesis and Immune-Regulative Effect of Adventitious Roots in Pseudostellaria heterophylla.

    Science.gov (United States)

    Wang, Juan; Li, Jing; Li, Hongfa; Wu, Xiaolei; Gao, Wenyuan

    2015-09-01

    A electrospray ionization tandem mass spectrometry (ESI-MS(n)) analysis was performed in order to identify the active composition in Pseudostellaria heterophylla adventitious roots. Pseudostellarin A, C, D, and G were identified from P. heterophylla adventitious roots on the basis of LC-MS(n) analysis. The culture conditions of adventitious roots were optimized, and datasets were subjected to a partial least squares discriminant analysis (PLS-DA), in which the growth ratio and some compounds showed a positive correlation with an aeration volume of 0.3 vvm and inoculum density of 0.15 %. Fed-batch cultivation enhanced the contents of total saponin, polysaccharides, and specific oxygen uptaker rate (SOUR). The maximum dry root weight (4.728 g l(-1)) was achieved in the 3/4 Murashige and Skoog (MS) medium group. PLS-DA showed that polysaccharides contributed significantly to the clustering of different groups and showed a positive correlation in the MS medium group. The delayed-type hypersensitivity (DTH) reaction on the mice induced by 2,4-dinitrofluorobenzene (DNFB) was applied to compare the immunocompetence effects of adventitious roots (AR) with field native roots (NR) of P. heterophylla. As a result, AR possessed a similar immunoregulation function as NR.

  4. Comparison of laser diffraction and image analysis for measurement of Streptomyces coelicolor cell clumps and pellets

    DEFF Research Database (Denmark)

    Rønnest, Nanna Petersen; Stocks, Stuart M; Eliasson Lantz, Anna

    2012-01-01

    and pellets of Streptomyces coelicolor compare to image analysis. Samples, taken five times during fed-batch cultivation, were analyzed by image analysis and laser diffraction. The volume-weighted size distribution was calculated for each sample. Laser diffraction and image analysis yielded similar size...

  5. High-level expression of a fungal pyranose oxidase in high cell-density fed-batch cultivations of Escherichia coli using lactose as inducer

    Czech Academy of Sciences Publication Activity Database

    Kotík, Michael; Kočanová, Marcela; Marešová, Helena; Kyslík, Pavel

    2004-01-01

    Roč. 36, - (2004), s. 61-69 ISSN 1046-5928 Institutional research plan: CEZ:AV0Z5020903 Keywords : fed-batch * lactose * inclusion bodies Subject RIV: EE - Microbiology, Virology Impact factor: 1.336, year: 2004

  6. 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 model for cultivation behaviour. This model is validated against 13 data sets and demonstrated to explain a significant amount of variation in the data. The multivariate model may directly be used for process monitoring. With this method faults are detected in real time and the responsible measurements...

  7. Water-saving analysis on an effective water reuse system in biodiesel feedstock production based on Chlorella zofingiensis fed-batch cultivation.

    Science.gov (United States)

    Yang, Kang; Qin, Lei; Wang, Zhongming; Feng, Wei; Feng, Pingzhong; Zhu, Shunni; Xu, Jingliang; Yuan, Zhenhong

    2015-01-01

    The micralgae-based biofuel obtained from dairy wastewater (DWW) is considered a promising source of energy. However, this process consumes water due to the concentration of wastewater being normally too high for some micoralgae cultivation, and dilution is always needed. In this work, the cultivation of microalgae has been examined in non-recirculated water (NR) and recirculated water systems (R). The growth of Chlorella zofingiensis and the nutrient removal of DWW have been recorded. The comparison indicates the R had a little more advantage in biomass and lipid output (1.55, 0.22 g, respectively) than the NR (1.51, 0.20 g, respectively). However, the total chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), and total phosphorus (TP) removals of the R were lower than those of the NR system during the culture. The highest removal of total COD, TKN, and TP were 85.05%, 93.64%, and 98.45%, respectively. Furthermore, no significant difference has been observed in the higher heating value and lipid content of the biomass of the R and NR. The results show the R can save 30% of the total water input during the culture. All above results indicate the R system has great potential in industry.

  8. Plasma modified PLA electrospun membranes for actinorhodin production intensification in Streptomyces coelicolor immobilized-cell cultivations.

    Science.gov (United States)

    Scaffaro, Roberto; Lopresti, Francesco; Sutera, Alberto; Botta, Luigi; Fontana, Rosa Maria; Gallo, Giuseppe

    2017-09-01

    Most of industrially relevant bioproducts are produced by submerged cultivations of actinomycetes. The immobilization of these Gram-positive filamentous bacteria on suitable porous supports may prevent mycelial cell-cell aggregation and pellet formation which usually negatively affect actinomycete submerged cultivations, thus, resulting in an improved biosynthetic capability. In this work, electrospun polylactic acid (PLA) membranes, subjected or not to O 2 -plasma treatment (PLA-plasma), were used as support for immobilized-cell submerged cultivations of Streptomyces coelicolor M145. This strain produces different bioactive compounds, including the blue-pigmented actinorhodin (ACT) and red-pigmented undecylprodigiosin (RED), and constitutes a model for the study of antibiotic-producing actinomycetes. Wet contact angles and X-ray photoelectron spectroscopy analysis confirmed the increased wettability of PLA-plasma due to the formation of polar functional groups such as carboxyl and hydroxyl moieties. Scanning electron microscope observations, carried out at different incubation times, revealed that S. coelicolor immobilized-cells created a dense "biofilm-like" mycelial network on both kinds of PLA membranes. Cultures of S. coelicolor immobilized-cells on PLA or PLA-plasma membranes produced higher biomass (between 1.5 and 2 fold) as well as higher levels of RED and ACT than planktonic cultures. In particular, cultures of immobilized-cells on PLA and PLA-plasma produced comparable levels of RED that were approximatively 4 and 5 fold higher than those produced by planktonic cultures, respectively. In contrast, levels of ACT produced by immobilized-cell cultures on PLA and PLA-plasma were different, being 5 and 10 fold higher than those of planktonic cultures, respectively. Therefore, this is study demonstrated the positive influence of PLA membrane on growth and secondary metabolite production in S. coelicolor and also revealed that O 2 -plasma treated PLA membranes

  9. Robust, small-scale cultivation platform for Streptomyces coelicolor

    DEFF Research Database (Denmark)

    Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan; Lantz, Anna Eliasson

    2012-01-01

    rates of antibiotics. CONCLUSION: We observed good agreement of the physiological data obtained in the developed MTP platform with bench-scale. Hence, the described MTP-based screening platform has a high potential for investigation of secondary metabolite biosynthesis in Streptomycetes and other....... The MTP cultivations were found to behave similar to bench-scale in terms of growth rate, productivity and substrate uptake rate and so was the onset of antibiotic synthesis. Shake flask cultivations however, showed discrepancy with respect to morphology and had considerably reduced volumetric production...

  10. 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.

  11. Optimization of cyclosporin A production by Beauveria nivea in continuous fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Dong Huijun

    2011-01-01

    Full Text Available To develop the effective control method for fed-batch culture of cyclosporin A production, we chose fructose, L-valine and (NH42HPO4 as feeding nutrients and compared their productivities in relation to different concentrations. The feeding rate of three kinds of feeding materials was controlled to maintain the suitable residual concentration. The fed-batch fermentation results indicated that the optimal concentrations of fructose, L-valine and (NH42HPO4 were about 20 g/L, 0.5 g/L and 0.6 g/L for cyclosporin A production, respectively. The cultivation of Beauveria nivea could produce cyclosporin A up to 6.2 g/L for 240 hrs through a continuous feeding-rate-controlled-batch process under the optimal feeding conditions.

  12. 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

  13. From Fed-batch to Continuous Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  14. Model-based intensification of a fed-batch microbial process for the maximization of polyhydroxybutyrate (PHB) production rate.

    Science.gov (United States)

    Penloglou, Giannis; Vasileiadou, Athina; Chatzidoukas, Christos; Kiparissides, Costas

    2017-08-01

    An integrated metabolic-polymerization-macroscopic model, describing the microbial production of polyhydroxybutyrate (PHB) in Azohydromonas lata bacteria, was developed and validated using a comprehensive series of experimental measurements. The model accounted for biomass growth, biopolymer accumulation, carbon and nitrogen sources utilization, oxygen mass transfer and uptake rates and average molecular weights of the accumulated PHB, produced under batch and fed-batch cultivation conditions. Model predictions were in excellent agreement with experimental measurements. The validated model was subsequently utilized to calculate optimal operating conditions and feeding policies for maximizing PHB productivity for desired PHB molecular properties. More specifically, two optimal fed-batch strategies were calculated and experimentally tested: (1) a nitrogen-limited fed-batch policy and (2) a nitrogen sufficient one. The calculated optimal operating policies resulted in a maximum PHB content (94% g/g) in the cultivated bacteria and a biopolymer productivity of 4.2 g/(l h), respectively. Moreover, it was demonstrated that different PHB grades with weight average molecular weights of up to 1513 kg/mol could be produced via the optimal selection of bioprocess operating conditions.

  15. A fast approach to determine a fed batch feeding profile for recombinant Pichia pastoris strains

    Directory of Open Access Journals (Sweden)

    Herwig Christoph

    2011-10-01

    Full Text Available Abstract Background The microorganism Pichia pastoris is a commonly used microbial host for the expression of recombinant proteins in biotechnology and biopharmaceutical industry. To speed up process development, a fast methodology to determine strain characteristic parameters, which are needed to subsequently set up fed batch feeding profiles, is required. Results Here, we show the general applicability of a novel approach to quantify a certain minimal set of bioprocess-relevant parameters, i.e. the adaptation time of the culture to methanol, the specific substrate uptake rate during the adaptation phase and the maximum specific substrate uptake rate, based on fast and easy-to-do batch cultivations with repeated methanol pulses in a batch culture. A detailed analysis of the adaptation of different P. pastoris strains to methanol was conducted and revealed that each strain showed very different characteristics during adaptation, illustrating the need of individual screenings for an optimal parameter definition during this phase. Based on the results obtained in batch cultivations, dynamic feeding profiles based on the specific substrate uptake rate were employed for different P. pastoris strains. In these experiments the maximum specific substrate uptake rate, which had been defined in batch experiments, also represented the upper limit of methanol uptake, underlining the validity of the determined process-relevant parameters and the overall experimental strategy. Conclusion In this study, we show that a fast approach to determine a minimal set of strain characteristic parameters based on easy-to-do batch cultivations with methanol pulses is generally applicable for different P. pastoris strains and that dynamic fed batch strategies can be designed on the specific substrate uptake rate without running the risk of methanol accumulation.

  16. A Genetic Algorithms Based Approach for Identification of Escherichia coli Fed-batch Fermentation

    Directory of Open Access Journals (Sweden)

    Olympia Roeva

    2004-10-01

    Full Text Available This paper presents the use of genetic algorithms for identification of Escherichia coli fed-batch fermentation process. Genetic algorithms are a directed random search technique, based on the mechanics of natural selection and natural genetics, which can find the global optimal solution in complex multidimensional search space. The dynamic behavior of considered process has known nonlinear structure, described with a system of deterministic nonlinear differential equations according to the mass balance. The parameters of the model are estimated using genetic algorithms. Simulation examples for demonstration of the effectiveness and robustness of the proposed identification scheme are included. As a result, the model accurately predicts the process of cultivation of E. coli.

  17. Production of nattokinase by high cell density fed-batch culture of Bacillus subtilis.

    Science.gov (United States)

    Kwon, Eun-Yeong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Beom Soo

    2011-09-01

    Bacillus subtilis was cultivated to high cell density for nattokinase production by pH-stat fed-batch culture. A concentrated mixture solution of glucose and peptone was automatically added by acid-supplying pump when culture pH rose above high limit. Effect of the ratio of glucose to peptone in feeding solution was investigated on cell growth and nattokinase production by changing the ratio from 0.2 to 5 g glucose/g peptone. The highest cell concentration was 77 g/L when the ratio was 0.2 g glucose/g peptone. Cell concentration decreased with increasing the ratio of glucose to peptone in feeding solution, while the optimum condition existed for nattokinase production. The highest nattokinase activity was 14,500 unit/mL at a ratio of 0.33 g glucose/g peptone, which was 4.3 times higher than that in batch culture.

  18. Hydrogen production from formic acid in pH-stat fed-batch operation for direct supply to fuel cell.

    Science.gov (United States)

    Shin, Jong-Hwan; Yoon, Jong Hyun; Lee, Seung Hoon; Park, Tai Hyun

    2010-01-01

    Enterobacter asburiae SNU-1 harvested after cultivation was used as a whole cell biocatalyst, for the production of hydrogen. Formic acid was efficiently converted to hydrogen using the harvested cells with an initial hydrogen production rate and total hydrogen production of 491 ml/l/h and 6668 ml/l, respectively, when 1 g/l of whole cell enzyme was used. Moreover, new pH-stat fed-batch operation was conducted, and total hydrogen production was 1.4 times higher than that of batch operation. For practical application, bio-hydrogen produced from formic acid using harvested cells was directly applied to PEMFC for power generation.

  19. Cloning, multicopy expression and fed-batch production of Rhodotorula araucariae epoxide hydrolase in yarrowia lipolytica

    CSIR Research Space (South Africa)

    Ramduth, D

    2008-05-01

    Full Text Available demonstrated a 4 fold enhanced EH activity over the transformant. The transformant was then evaluated in batch and fed batch fermentations, where the batch fermentations resulted in - 50% improved EH activity from flask evaluations. In fed batch fermentations...

  20. 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

    carbohydrates than from glucose or xylose. Although high biomass and lipid production were achieved in both batch and fed-batch cultures with glucose as carbon source, for lipid production from mixtures of carbohydrates fed-batch cultivation was preferable. Constant feeding was better than intermittent feeding. The feeding strategy did not affect the relative proportion of different fatty acids in the lipid, but the presence of C5 sugars did.

  1. 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......-transfer to manufacturing scale. In this chapter, we will describe stepwise how to carry out fed-batch CHO cell culture for lab-scale antibody production....

  2. A fed-batch strategy to produce high poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) terpolymer yield with enhanced mechanical properties in bioreactor.

    Science.gov (United States)

    Aziz, Nursolehah Abd; Huong, Kai-Hee; Sipaut, Coswald Stephen; Amirul, A A

    2017-11-01

    This study reports an efficient fed-batch strategy to improve poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-3HV-co-4HB)] terpolymer production by Cupriavidus sp. USMAA2-4 with enhanced mechanical properties in bioreactor. The cultivations have been performed by combining oleic acid with γ-butyrolactone at different concentration ratios with 1-pentanol at a fixed concentration. The batch and fed-batch fermentations have resulted in P(3HB-co-3HV-co-4HB) with compositions of 9-35 mol% 3HV and 4-24 mol% 4HB monomers. The DO-stat fed-batch fermentation strategies have significantly improved the production with a maximum 4.4-fold increment of cell dry weight (CDW). Besides, appropriate feeding of the substrates has resulted in an increment of terpolymer productivity from 0.086-0.347 g/L/h, with a significantly shortened cultivation time. The bacterial growth and terpolymer formation have been found to be affected by the concentration of carbon sources supplied. Characterization of P(3HB-co-3HV-co-4HB) has demonstrated that incorporation of 3HV and 4HB monomer has significantly improved the physical and thermodynamic properties of the polymers, by reducing the polymer's crystallinity. The tensile strength, Young's modulus of the terpolymer has been discovered to increase with the increase of M w . The fed-batch fermentation strategies employed in this study have resulted in terpolymers with a range of flexible materials having improved tensile strength and Young's modulus as compared to the terpolymer produced from batch fermentation. Possession of lower melting temperature indicates an enhanced thermal stability which broadens the polymer processing window.

  3. The use of fed batch approaches to maximise yields in bacterial fermentation and protein expression

    International Nuclear Information System (INIS)

    McLean, A.

    2001-01-01

    A fermentation facility for the scale up of bacterial and yeast fermentations has been set up at the University of Queensland under the auspices of the ARC Special Research Centre for Functional and Applied Genomics. A major application is the production of recombinant proteins for determination of tertiary structures by X-ray crystallography or nuclear magnetic resonance. For this purpose, large amounts of protein arc needed and the yield from a single fermentation run is crucial to success within constrained laboratory budgets. To achieve maximal yields we are optimising fed batch approaches in bacterial fermentation. Fed batch offers many advantages over batch cultures. Coupled with the ability to monitor online the internal conditions of the fermentation including pH and dissolved oxygen and stirrer cascading functions it is possible to ensure that the nutritional environment of the microorganism is optimised for its growth and or for optimal protein expression. The poster will describe some of our experience in setting up fed batch fermentations and successful applications of fed batches to increasing protein yield. It will also outline services that are available to academic groups outside the University of Queensland For structure determination and functional studies, the production of radiolabelled proteins can also be an advantage. We will describe initial experiments aimed at coupling the principles of fed batch fermentation to the introduction of carbon or nitrogen isotopes into the recombinant protein

  4. Simulation of kefiran production of Lactobacillus kefiranofaciens JCM6985 in fed-batch reactor

    Directory of Open Access Journals (Sweden)

    Benjamas Cheirsilp

    2006-09-01

    Full Text Available Kinetics of kefiran production by Lactobacillus kefiranofaciens JCM6985 has been investigated. A mathematical model taking into account the mechanism of exopolysaccharides production has been developed. Experiments were carried out in batch mode in order to obtain kinetic model parameters that were further applied to simulate fed-batch processes. A simplification of parameter fitting was also introduced for complicated model. The fed-batch mode allows more flexibility in the control of the substrate concentration as well as product concentration in the culture medium. Based on the batch mathematical model, a fed-batch model was developed and simulations were done. Simulation study in fed-batch reactor resulted that substrate concentration should be controlled at 20 g L-1 to soften the product inhibition and also to stimulate utilization of substrate and its hydrolysate. From simulation results of different feeding techniques, it was found that constant feeding at 0.01 L h-1 was most practically effective feeding profile for exopolysaccharides production in fed-batch mode.

  5. Glycoprofiling effects of media additives on IgG produced by CHO cells in fed-batch bioreactors

    DEFF Research Database (Denmark)

    Kildegaard, Helene Faustrup; Fan, Yuzhou; Wagtberg Sen, Jette

    2016-01-01

    Therapeutic monoclonal antibodies (mAbs) are mainly produced by heterogonous expression in Chinese hamster ovary (CHO) cells. The glycosylation profile of the mAbs has major impact on the efficacy and safety of the drug and is therefore an important parameter to control during production. In this......Therapeutic monoclonal antibodies (mAbs) are mainly produced by heterogonous expression in Chinese hamster ovary (CHO) cells. The glycosylation profile of the mAbs has major impact on the efficacy and safety of the drug and is therefore an important parameter to control during production....... In this study, the effect on IgG N-glycosylation from feeding CHO cells with eight glycosylation precursors during cultivation was investigated. The study was conducted in fed-batch mode in bioreactors with biological replicates to obtain highly controlled and comparable conditions. We assessed charge...

  6. Fructose production by Zymomonas mobilis in fed-batch culture with minimal sorbitol formation

    Energy Technology Data Exchange (ETDEWEB)

    Edye, L A; Johns, M R; Ewings, K N

    1989-08-01

    Fed-batch cultures of Zymomonas mobilis (UQM 2864), a mutant unable to metabolise fructose, grown on diluted sugar cane syrup (200 g/l sucrose) achieved yields of 90.5 g/l fructose and 48.3 g/l ethanol with minimal sorbitol formation and complete utilization of the substrate. The effect of inoculum size on sorbitol formation in the batch stage of fed-batch fermentation are reported. Fermentation of sucrose (350 g/l) supplemented with nutrients yielded 142 g/l fructose and 76.5 g/l ethanol. Some fructose product loss at high fructose concentrations was observed. The fed-batch fermentation process offers a method for obtaining high concentrations of fructose and ethanol from sucrose materials. (orig.).

  7. A high-yielding, generic fed-batch process for recombinant antibody production of GS-engineered cell lines

    DEFF Research Database (Denmark)

    Fan, Li; Zhao, Liang; Sun, Yating

    2009-01-01

    An animal component-free and chemically defined fed-batch process for GS-engineered cell lines producing recombinant antibodies has been developed. The fed-batch process relied on supplying sufficient nutrients to match their consumption, simultaneously minimizing the accumulation of byproducts....... This generic and high-yielding fed-batch process would shorten development time, and ensure process stability, thereby facilitating the manufacture of therapeutic antibodies by GS-engineered cell lines....

  8. Fed-batch and perfusion culture processes: economic, environmental, and operational feasibility under uncertainty.

    Science.gov (United States)

    Pollock, James; Ho, Sa V; Farid, Suzanne S

    2013-01-01

    This article evaluates the current and future potential of batch and continuous cell culture technologies via a case study based on the commercial manufacture of monoclonal antibodies. The case study compares fed-batch culture to two perfusion technologies: spin-filter perfusion and an emerging perfusion technology utilizing alternating tangential flow (ATF) perfusion. The operational, economic, and environmental feasibility of whole bioprocesses based on these systems was evaluated using a prototype dynamic decision-support tool built at UCL encompassing process economics, discrete-event simulation and uncertainty analysis, and combined with a multi-attribute decision-making technique so as to enable a holistic assessment. The strategies were compared across a range of scales and titres so as to visualize how their ranking changes in different industry scenarios. The deterministic analysis indicated that the ATF perfusion strategy has the potential to offer cost of goods savings of 20% when compared to conventional fed-batch manufacturing processes when a fivefold increase in maximum viable cell densities was assumed. Savings were also seen when the ATF cell density dropped to a threefold increase over the fed-batch strategy for most combinations of titres and production scales. In contrast, the fed-batch strategy performed better in terms of environmental sustainability with a lower water and consumable usage profile. The impact of uncertainty and failure rates on the feasibility of the strategies was explored using Monte Carlo simulation. The risk analysis results demonstrated the enhanced robustness of the fed-batch process but also highlighted that the ATF process was still the most cost-effective option even under uncertainty. The multi-attribute decision-making analysis provided insight into the limited use of spin-filter perfusion strategies in industry. The resulting sensitivity spider plots enabled identification of the critical ratio of weightings of

  9. 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

    was found to be limited by UDP-Gal biosynthesis, which was observed to be both cell line and cultivation condition-dependent. Extracellular glucose and glutamine concentrations and uptake rates were positively correlated with intracellular UDP-Gal availability. All these findings are important for optimization of fed-batch culture for improving IgG production and directing glycosylation quality. © 2014 Wiley Periodicals, Inc.

  10. High solid fed-batch butanol fermentation with simultaneous product recovery: part II - process integration.

    Science.gov (United States)

    In these studies liquid hot water (LHW) pretreated and enzymatically hydrolyzed Sweet Sorghum Bagasse (SSB) hydrolyzates were fermented in a fed-batch reactor. As reported in the preceding paper, the culture was not able to ferment the hydrolyzate I in a batch process due to presence of high level o...

  11. Fed-batch fermentation dealing with nitrogen limitation in microbial transglutaminase production by Streptoverticillium mobaraense

    NARCIS (Netherlands)

    Rinzema, A; Tramper, J; de Bruin, E; Bol, J

    In the later stages of a batch fermentation for microbial transglutaminase production by Streptoverticillium mobaraense the availability of a nitrogen source accessible to the microorganism becomes critical. Fed-batch fermentation is investigated with the aim of avoiding this substrate limitation.

  12. Optimization of fed-batch fermentation for xylitol production by Candida tropicalis.

    Science.gov (United States)

    Kim, J-H; Han, K-C; Koh, Y-H; Ryu, Y-W; Seo, J-H

    2002-07-01

    Xylitol, a functional sweetener, was produced from xylose by biological conversion using Candida tropicalis ATCC 13803. Based on a two-substrate fermentation using glucose for cell growth and xylose for xylitol production, fed-batch fermentations were undertaken to increase the final xylitol concentration. The effects of xylose and xylitol on xylitol production rate were studied to determine the optimum concentrations for fed-batch fermentation. Xylose concentration in the medium (100 g l(-1)) and less than 200 g l(-1) total xylose plus xylitol concentration were determined as optimum for maximum xylitol production rate and xylitol yield. Increasing the concentrations of xylose and xylitol decreased the rate and yield of xylitol production and the specific cell growth rate, probably because of an increase in osmotic stress that would interfere with xylose transport, xylitol flux to secretion to cell metabolism. The feeding rate of xylose solution during the fed-batch mode of operation was determined by using the mass balance equations and kinetic parameters involved in the equations in order to increase final xylitol concentration without affecting xylitol and productivity. The optimized fed-batch fermentation resulted in 187 g l(-1) xylitol concentration, 0.75 g xylitol g xylose(-1) xylitol yield and 3.9 g xylitol l(-1) h(-1) volumetric productivity.

  13. 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

  14. Facilitating control of fed-batch fermentation processes by monitoring the growth rates of saccharomyces cerevisiae

    NARCIS (Netherlands)

    Keulers, M.L.B.; Ariaans, L.J.J.M.; Soeterboek, R.; Giuseppin, M.

    1994-01-01

    In this paper we present a growth rate controller for a fed-batch bioprocess. An observer estimates the growth rate. The observer is based on knowledge about the stoichiometric relations of the process. Furthermore, the observer needs online measurements of the oxygen uptake rate and the

  15. Optimization of fed-batch fermentation for a staphylokinase-hirudin ...

    African Journals Online (AJOL)

    TUOYO

    2010-08-09

    Aug 9, 2010 ... In this study, the fed-batch fermentation technique was applied to improve the yield of STH, a chimeric protein composed ... Under optimal conditions (GMYT and complex medium), a final STH expression of 1.48 g/l fermentation broth was ... STH production contained the following materials (per L): Sucrose.

  16. Optimization of a fed-batch fermentation process for production of ...

    African Journals Online (AJOL)

    user

    2011-02-28

    Feb 28, 2011 ... fermentation. Overall, this study suggested that fed-batch fermentation can be successfully used to ... catalysts that catalyze their own synthesis. Enzymes are .... shows the amount of biomass (g l−1) in the fermentation broth of ...

  17. 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.

  18. Nonlinear impulsive system of fed-batch culture in fermentative production and its properties

    International Nuclear Information System (INIS)

    Gao Caixia; Li Kezan; Feng Enmin; Xiu Zhilong

    2006-01-01

    In this study, the nonlinear dynamical system of fed-batch fermentation is investigated in the process of bio-dissimilation of glycerol to 1,3-propanediol by Klebsiella pneumoniae. Considering the abrupt increase of glycerol in fed-batch culture, this paper proposes a nonlinear impulsive system of the culture process, which is fit for formulating the factual fermentation better than the continuous models in being. We study the questions of existence and properties of mild solutions for the system and the continuous dependence of solutions on initial values and the controllable variable. Finally, the numerical simulations show that the errors between experimental and computational values using the impulsive system are less than those using the previous continuous system

  19. Modeling and parameters identification of 2-keto-L-gulonic acid fed-batch fermentation.

    Science.gov (United States)

    Wang, Tao; Sun, Jibin; Yuan, Jingqi

    2015-04-01

    This article presents a modeling approach for industrial 2-keto-L-gulonic acid (2-KGA) fed-batch fermentation by the mixed culture of Ketogulonicigenium vulgare (K. vulgare) and Bacillus megaterium (B. megaterium). A macrokinetic model of K. vulgare is constructed based on the simplified metabolic pathways. The reaction rates obtained from the macrokinetic model are then coupled into a bioreactor model such that the relationship between substrate feeding rates and the main state variables, e.g., the concentrations of the biomass, substrate and product, is constructed. A differential evolution algorithm using the Lozi map as the random number generator is utilized to perform the model parameters identification, with the industrial data of 2-KGA fed-batch fermentation. Validation results demonstrate that the model simulations of substrate and product concentrations are well in coincidence with the measurements. Furthermore, the model simulations of biomass concentrations reflect principally the growth kinetics of the two microbes in the mixed culture.

  20. Simulation of Feedforward-Feedback Control of Dissolved Oxygen of Microbial Repeated Fed-batch Culture

    Directory of Open Access Journals (Sweden)

    Ling Gao

    2016-09-01

    Full Text Available Fed-batch culture is often used in industry, and dissolved oxygen (DO concentration control is important in fermentation process control. DO control is often applied by using feedback (FB control strategy. But, feedforward-feedback (FF-FB control has the advantage in dealing with the time-varying characteristics resulted from the cell growth during the fermentation process. Mathematical modeling and computer simulation is a useful tool in analysis of the control system.  In this research, the FF-FB DO control and FB substrate control of repeated fed-batch culture process is modeled and simulated. The results showed the feasibility of the control strategy. These results are useful for control system development and process analyses and optimization.

  1. Fed-Batch Biomolecule Production by Bacillus subtilis: A State of the Art Review.

    Science.gov (United States)

    Ÿztürk, Sibel; Ÿalık, Pınar; Ÿzdamar, Tunçer H

    2016-04-01

    Bacillus subtilis is a highly promising production system for various biomolecules. This review begins with the algorithm of fed-batch operations (FBOs) and then illustrates the approaches to design the initial production medium and/or feed stream. Additionally, the feeding strategies developed with or without feedback control for fed-batch B. subtilis fermentations were compiled with a special emphasis on recombinant protein (r-protein) production. For biomolecule production by wild-type B. subtilis, due to the different intracellular production patterns, no consensus exists on the FBO strategy that gives the maximum productivity, whereas for r-protein production appropriate feeding strategies vary depending on the promoter used. Thus, we conclude that the B. subtilis community is still seeking an approved strong promoter and generalized FBO strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. 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.

  3. Continuous fed-batch vacuum fermentation system for glycerol from molasses by the sulfite process

    Energy Technology Data Exchange (ETDEWEB)

    Kalle, G.P.; Naik, S.C.

    1985-01-01

    A continuous fed-batch vacuum fermentation system has been described for the production of glycerol from cane molasses (and juice) by a conventional sulfite process. A glycerol concentration of 80 g/l was achieved with a productivity of 30 g/l/day at a dilution rate of 0.4/day which is twice that from a vacuum batch process (15 g/l/day) or four times that obtained without vacuum (8 g/l/day). 8 references.

  4. Modelling and properties of a nonlinear autonomous switching system in fed-batch culture of glycerol

    Science.gov (United States)

    Wang, Juan; Sun, Qingying; Feng, Enmin

    2012-11-01

    A nonlinear autonomous switching system is proposed to describe the coupled fed-batch fermentation with the pH as the feedback parameter. We prove the non-Zeno behaviors of the switching system and some basic properties of its solution, including the existence, uniqueness, boundedness and regularity. Numerical simulation is also carried out, which reveals that the proposed system can describe the factual fermentation process properly.

  5. Modelling of Fed-batch Fermentation Process with Droppings for L-lysine Production

    Directory of Open Access Journals (Sweden)

    Velitchka Ivanova

    2006-04-01

    Full Text Available The aim of the article is the development of dynamic unstructured model of L-lysine fed-batch fermentation process with droppings. This approach includes the following procedures: description of the process by generalized stoichiometric equations; preliminary data processing; identification of the specific rates (growth rate (mu , substrate utilization rate (nu, production rate (rho; establishment and optimization of the dynamic model of the process; simulation researches.

  6. Degradation of chlorophenol mixtures in a fed-batch system by two ...

    African Journals Online (AJOL)

    This work was undertaken to investigate the effect of variations of the feed rate on a fed-batch set-up used to degrade xenobiotics. The mixture of substrates was composed of PCP, 2,4,6 TCP and 2,3,5,6 TeCP (pentachlorophenol, 2,4,6 trichlorophenol and 2,3,5,6 tetrachlorophenol respectively). Two acclimated bacteria ...

  7. 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

  8. Fed-batch coculture of Lactobacillus kefiranofaciens with Saccharomyces cerevisiae for effective production of kefiran.

    Science.gov (United States)

    Tada, Shiori; Katakura, Yoshio; Ninomiya, Kazuaki; Shioya, Suteaki

    2007-06-01

    In a batch coculture of kefiran-producing lactic acid bacteria Lactobacillus kefiranofaciens and lactate-assimilating yeast Saccharomyces cerevisiae, lactate accumulation in the medium was observed, which inhibited kefiran production. To enhance kefiran productivity by preventing lactate accumulation, we conducted lactose-feeding batch operation with feedforward/feedback control during the coculture, so that the lactate production rate of L. kefiranofaciens was balanced with the lactate consumption rate of S. cerevisiae. The lactate concentration was maintained at less than 6 g l(-1) throughout the fed-batch coculture using a 5 l jar fermentor, although the concentration reached 33 g l(-1) in the batch coculture. Kefiran production was increased to 6.3 g in 102 h in the fed-batch coculture, whereas 4.5 g kefiran was produced in 97 h in the batch coculture. The kefiran yield on lactose basis was increased up to 0.033 g g(-1) in the fed-batch coculture, whereas that in the batch coculture was 0.027 g g(-1).

  9. Optimization of high solids fed-batch saccharification of sugarcane bagasse based on system viscosity changes.

    Science.gov (United States)

    Liu, Yunyun; Xu, Jingliang; Zhang, Yu; Yuan, Zhenhong; Xie, Jun

    2015-10-10

    Viscosity trends in alkali-pretreated sugarcane bagasse (SCB) slurries undergoing high solids fed-batch enzymatic hydrolysis were measured for a range of solids loading from 15% to 36%. Solids liquefaction times were related to system viscosity changes. The viscosity decreased quickly for low solids loading, and increased with increasing solids content. Fed-batch hydrolysis was initiated with 15% solids loading, and an additional 8%, 7% and 6% were successively added after the system viscosity decreased to stable values to achieve a final solids content of 36%. Two enzyme-adding modes with 8.5FPU/g solid were investigated. The batch mode with all enzyme being added at the beginning of the reaction produced the highest yields, with approximately 231.7g/L total sugars and 134.9g/L glucose being obtained after 96h with nearly 60% of the final glucan conversion rate. This finding indicates that under the right conditions, the fed-batch strategy might be a plausible way to produce high sugars under high solids. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Effect of auxotrophies on yeast performance in aerated fed-batch reactor

    Energy Technology Data Exchange (ETDEWEB)

    Landi, Carmine; Paciello, Lucia [Dept. Ingegneria Industriale, Universita di Salerno, Via Ponte Don Melillo, 84084 Fisciano, Salerno (Italy); Alteriis, Elisabetta de [Dept. Biologia Strutturale e Funzionale, Universita degli Studi di Napoli ' Federico II' , Via Cinthia, 80100 Napoli (Italy); Brambilla, Luca [Dept. Biotecnologie e Bioscienze, Universita Milano-Bicocca, Piazza della Scienza, 20126 Milano (Italy); Parascandola, Palma, E-mail: pparascandola@unisa.it [Dept. Ingegneria Industriale, Universita di Salerno, Via Ponte Don Melillo, 84084 Fisciano, Salerno (Italy)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer The paper contributes to fill the gap existing between the basic and applied research. Black-Right-Pointing-Pointer Mathematical model sheds light on the physiology of auxotrophic yeast strains. Black-Right-Pointing-Pointer Yeast behavior in fed-batch is influenced by biological and environmental determinants. Black-Right-Pointing-Pointer Process optimization would make possible the production of heterologous proteins which are not yet on the market. -- Abstract: A systematic investigation on the effects of auxotrophies on the performance of yeast in aerated fed-batch reactor was carried out. Six isogenic strains from the CEN.PK family of Saccharomyces cerevisiae, one prototroph and five auxotrophs, were grown in aerated fed-batch reactor using the same operative conditions and a proper nutritional supplementation. The performance of the strains, in terms of final biomass decreased with increasing the number of auxotrophies. Auxotrophy for leucine exerted a profound negative effect on the performance of the strains. Accumulation of reactive oxygen species (ROS) in the cells of the strain carrying four auxotrophies and its significant viability loss, were indicative of an oxidative stress response induced by exposure of cells to the environmental conditions. The mathematical model was fundamental to highlight how the carbon flux, depending on the number and type of auxotrophies, was diverted towards the production of increasingly large quantities of energy for maintenance.

  11. Effect of auxotrophies on yeast performance in aerated fed-batch reactor

    International Nuclear Information System (INIS)

    Landi, Carmine; Paciello, Lucia; Alteriis, Elisabetta de; Brambilla, Luca; Parascandola, Palma

    2011-01-01

    Highlights: ► The paper contributes to fill the gap existing between the basic and applied research. ► Mathematical model sheds light on the physiology of auxotrophic yeast strains. ► Yeast behavior in fed-batch is influenced by biological and environmental determinants. ► Process optimization would make possible the production of heterologous proteins which are not yet on the market. -- Abstract: A systematic investigation on the effects of auxotrophies on the performance of yeast in aerated fed-batch reactor was carried out. Six isogenic strains from the CEN.PK family of Saccharomyces cerevisiae, one prototroph and five auxotrophs, were grown in aerated fed-batch reactor using the same operative conditions and a proper nutritional supplementation. The performance of the strains, in terms of final biomass decreased with increasing the number of auxotrophies. Auxotrophy for leucine exerted a profound negative effect on the performance of the strains. Accumulation of reactive oxygen species (ROS) in the cells of the strain carrying four auxotrophies and its significant viability loss, were indicative of an oxidative stress response induced by exposure of cells to the environmental conditions. The mathematical model was fundamental to highlight how the carbon flux, depending on the number and type of auxotrophies, was diverted towards the production of increasingly large quantities of energy for maintenance.

  12. Improving cellulase productivity of Penicillium oxalicum RE-10 by repeated fed-batch fermentation strategy.

    Science.gov (United States)

    Han, Xiaolong; Song, Wenxia; Liu, Guodong; Li, Zhonghai; Yang, Piao; Qu, Yinbo

    2017-03-01

    Medium optimization and repeated fed-batch fermentation were performed to improve the cellulase productivity by P. oxalicum RE-10 in submerged fermentation. First, Plackett-Burman design (PBD) and central composite design (CCD) were used to optimize the medium for cellulase production. PBD demonstrated wheat bran and NaNO 3 had significant influences on cellulase production. The CCD results showed the maximum filter paper activity (FPA) production of 8.61U/mL could be achieved in Erlenmeyer flasks. The maximal FPA reached 12.69U/mL by submerged batch fermentation in a 7.5-L stirred tank, 1.76-fold higher than that on the original medium. Then, the repeated fed-batch fermentation strategy was performed successfully for increasing the cellulase productivity from 105.75U/L/h in batch fermentation to 158.38U/L/h. The cellulase activity and the glucan conversion of delignined corn cob residue hydrolysis had no significant difference between the enzymes sampled from different cycles of the repeated fed-batch fermentation and that from batch culture. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. High cell density fed-batch fermentations for lipase production: feeding strategies and oxygen transfer.

    Science.gov (United States)

    Salehmin, M N I; Annuar, M S M; Chisti, Y

    2013-11-01

    This review is focused on the production of microbial lipases by high cell density fermentation. Lipases are among the most widely used of the enzyme catalysts. Although lipases are produced by animals and plants, industrial lipases are sourced almost exclusively from microorganisms. Many of the commercial lipases are produced using recombinant species. Microbial lipases are mostly produced by batch and fed-batch fermentation. Lipases are generally secreted by the cell into the extracellular environment. Thus, a crude preparation of lipases can be obtained by removing the microbial cells from the fermentation broth. This crude cell-free broth may be further concentrated and used as is, or lipases may be purified from it to various levels. For many large volume applications, lipases must be produced at extremely low cost. High cell density fermentation is a promising method for low-cost production: it allows a high concentration of the biomass and the enzyme to be attained rapidly and this eases the downstream recovery of the enzyme. High density fermentation enhances enzyme productivity compared with the traditional submerged culture batch fermentation. In production of enzymes, a high cell density is generally achieved through fed-batch operation, not through perfusion culture which is cumbersome. The feeding strategies used in fed-batch fermentations for producing lipases and the implications of these strategies are discussed. Most lipase-producing microbial fermentations require oxygen. Oxygen transfer in such fermentations is discussed.

  14. Effect of moisture content on fed batch composting reactor of vegetable and fruit wastes.

    Science.gov (United States)

    Jolanun, B; Tripetchkul, S; Chiemchaisri, C; Chaiprasert, P; Towprayoon, S

    2005-03-01

    Vegetable and fruit wastes mixed with sawdust were composted in a laboratory scale reactor by controlling the waste feeding rate at 21 kg m(-3) day(-1) and aeration rate at 10.6 l m(-3) min(-1). The effects of initial moisture content on organic matter degradation and process performance of fed batch composting were investigated. The absolute amount of removal, removal percentage, and removal rate of dry mass obtained were substantially different among the initial moisture contents. The rapid rise of moisture content and the lowest absolute amount of removal observed were achieved in the 50% condition. The initial moisture content yielding the largest absolute amount of removal in both feeding and curing stage was 30% whereas the removal percentage and rate constant of waste decomposition were highest in the 50% condition. Examined by traditional soil physics method, the moisture content at 50-55% was suitable for satisfying the degree of free air space (65-70%) of compost during the fed batch composting. Most degradable organic matter was mainly consumed in the feeding stage as indicated by a higher removal rate of dry mass in all cases. It is recommended that the initial moisture content of 30% and mode of aeration and agitation should be adopted for achieving practical fed batch composting of vegetable and fruit wastes. The study also demonstrated that the composting kinetics of vegetable and fruit wastes mixed with sawdust can be described by a first order model.

  15. Electrochemical study of multi-electrode microbial fuel cells under fed-batch and continuous flow conditions

    KAUST Repository

    Ren, Lijiao; Ahn, Yongtae; Hou, Huijie; Zhang, Fang; Logan, Bruce E.

    2014-01-01

    together (combined), in fed-batch or continuous flow conditions. Power production under these different conditions could not be made based on a single resistance, but instead required polarization tests to assess individual performance relative

  16. Perfusion cell culture decreases process and product heterogeneity in a head-to-head comparison with fed-batch.

    Science.gov (United States)

    Walther, Jason; Lu, Jiuyi; Hollenbach, Myles; Yu, Marcella; Hwang, Chris; McLarty, Jean; Brower, Kevin

    2018-05-30

    In this study, we compared the impacts of fed-batch and perfusion platforms on process and product attributes for IgG1- and IgG4-producing cell lines. A "plug-and-play" approach was applied to both platforms at bench scale, using commercially available basal and feed media, a standard feed strategy for fed-batch, and ATF filtration for perfusion. Product concentration in fed-batch was 2.5 times greater than perfusion, while average productivity in perfusion was 7.5 times greater than fed-batch. PCA revealed more variability in the cell environment and metabolism during the fed-batch run. LDH measurements showed that exposure of product to cell lysate was 7-10 times greater in fed-batch. Product analysis shows larger abundances of neutral species in perfusion, likely due to decreased bioreactor residence times and extracellular exposure. The IgG1 perfusion product also had higher purity and lower half-antibody. Glycosylation was similar across both culture modes. The first perfusion harvest slice for both product types showed different glycosylation than subsequent harvests, suggesting that product quality lags behind metabolism. In conclusion, process and product data indicate that intra-lot heterogeneity is decreased in perfusion cultures. Additional data and discussion is required to understand the developmental, clinical and commercial implications, and in what situations increased uniformity would be beneficial. This article is protected by copyright. All rights reserved.

  17. One Approach for Dynamic L-lysine Modelling of Repeated Fed-batch Fermentation

    Directory of Open Access Journals (Sweden)

    Kalin Todorov

    2007-03-01

    Full Text Available This article deals with establishment of dynamic unstructured model of variable volume fed-batch fermentation process with intensive droppings for L-lysine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates as a second-order non-linear dynamic models; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  18. A novel model-based control strategy for aerobic filamentous fungal fed-batch fermentation processes

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Albaek, Mads O.

    2017-01-01

    A novel model-based control strategy has been developed for filamentous fungal fed-batch fermentation processes. The system of interest is a pilot scale (550 L) filamentous fungus process operating at Novozymes A/S. In such processes, it is desirable to maximize the total product achieved...... is recursively updated using on-line measurements. The model was applied in order to predict the current system states, including the biomass concentration, and to simulate the expected future trajectory of the system until a specified end time. In this way, the desired feed rate is updated along the progress...

  19. Omega-3 production by fermentation of Yarrowia lipolytica: From fed-batch to continuous.

    Science.gov (United States)

    Xie, Dongming; Miller, Edward; Sharpe, Pamela; Jackson, Ethel; Zhu, Quinn

    2017-04-01

    The omega-3 fatty acid, cis-5,8,11,14,17-eicosapentaenoic acid (C20:5; EPA) has wide-ranging benefits in improving heart health, immune function, and mental health. A sustainable source of EPA production through fermentation of metabolically engineered Yarrowia lipolytica has been developed. In this paper, key fed-batch fermentation conditions were identified to achieve 25% EPA in the yeast biomass, which is so far the highest EPA titer reported in the literature. Dynamic models of the EPA fermentation process were established for analyzing, optimizing, and scaling up the fermentation process. In addition, model simulations were used to develop a two-stage continuous process and compare to single-stage continuous and fed- batch processes. The two stage continuous process, which is equipped with a smaller growth fermentor (Stage 1) and a larger production fermentor (Stage 2), was found to be a superior process to achieve high titer, rate, and yield of EPA. A two-stage continuous fermentation experiment with Y. lipolytica strain Z7334 was designed using the model simulation and then tested in a 2 L and 5 L fermentation system for 1,008 h. Compared with the standard 2 L fed-batch process, the two-stage continuous fermentation process improved the overall EPA productivity by 80% and EPA concentration in the fermenter by 40% while achieving comparable EPA titer in biomass and similar conversion yield from glucose. During the long-term experiment it was also found that the Y. lipolytica strain evolved to reduce byproduct and increase lipid production. This is one of the few continuous fermentation examples that demonstrated improved productivity and concentration of a final product with similar conversion yield compared with a fed-batch process. This paper suggests the two-stage continuous fermentation could be an effective process to achieve improved production of omega-3 and other fermentation products where non-growth or partially growth associated kinetics

  20. Optimal Control of a Fed-Batch Fermentation Involving Multiple Feeds

    Directory of Open Access Journals (Sweden)

    Chongyang Liu

    2012-01-01

    Full Text Available A nonlinear dynamical system, in which the feed rates of glycerol and alkali are taken as the control functions, is first proposed to formulate the fed-batch culture of 1,3-propanediol (1,3-PD production. To maximize the 1,3-PD concentration at the terminal time, a constrained optimal control model is then presented. A solution approach is developed to seek the optimal feed rates based on control vector parametrization method and improved differential evolution algorithm. The proposed methodology yielded an increase by 32.17% of 1,3-PD concentration at the terminal time.

  1. Fed-batch production of concentrated fructose syrup and ethanol using Saccharomyces cerevisiae ATCC 36859

    Energy Technology Data Exchange (ETDEWEB)

    Koren, D W [CANMET, Ottawa, ON (Canada); Duvnjak, Z [Univ. of Ottawa, ON (Canada). Dept. of Chemical Engineering

    1992-01-01

    A fed-batch process is used for the production of concentrated pure fructose syrup and ethanol from various glucose/fructose mixtures by S.cerevisiae ATCC 36859. Applying this technique, glucose-free fructose syrups with over 250 g/l of this sugar were obtained using High Fructose Corn Syrup and hydrolyzed Jerusalem artichoke juice. Bey encouraging ethanol evaporation from the reactor and condensing it, a separate ethanol product with a concentration of up to 350 g/l was also produced. The rates of glucose consumption and ethanol production were higher than in classical batch ethanol fermentation processes. (orig.).

  2. 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.

  3. Fed-batch production of vanillin by Bacillus aryabhattai BA03.

    Science.gov (United States)

    Paz, Alicia; Outeiriño, David; Pinheiro de Souza Oliveira, Ricardo; Domínguez, José Manuel

    2018-01-25

    Bacillus aryabhattai BA03, a strain isolated in our laboratory, has interesting properties related to the production of natural aromas and flavors. Specifically, we have found that it was able to produce vanillin from ferulic acid (FA). Furthermore, this strain produces high amounts of 4-vinylguaiacol in only 14h, this being the only intermediate metabolite observed in the process. FA is an inexpensive feedstock for the production of natural value-added compounds when extracted from lignocellulosic wastes. In this study, we optimized the operational conditions (temperature, pH and agitation), medium composition and bioconversion technology (batch or fed-batch) to produce vanillin. In a fed-batch process conducted with just one additional supplementation after 24h, the maximal concentration of vanillin (147.1±0.9mg/L) was observed after 216h (Q V =0.681mg/Lh; Y V/fFA =0.082mg/mg) after degrading 90.3% FA. In view of our data, we postulate that Bacillus aryabhattai BA03 carries out a decarboxylation of ferulic acid as a metabolic pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Bacteriocin Production with Lactobacillus amylovorus DCE 471 Is Improved and Stabilized by Fed-Batch Fermentation

    Science.gov (United States)

    Callewaert, Raf; De Vuyst, Luc

    2000-01-01

    Amylovorin L471 is a small, heat-stable, and hydrophobic bacteriocin produced by Lactobacillus amylovorus DCE 471. The nutritional requirements for amylovorin L471 production were studied with fed-batch fermentations. A twofold increase in bacteriocin titer was obtained when substrate addition was controlled by the acidification rate of the culture, compared with the titers reached with constant substrate addition or pH-controlled batch cultures carried out under the same conditions. An interesting feature of fed-batch cultures observed under certain culture conditions (constant feed rate) is the apparent stabilization of bacteriocin activity after obtaining maximum production. Finally, a mathematical model was set up to simulate cell growth, glucose and complex nitrogen source consumption, and lactic acid and bacteriocin production kinetics. The model showed that bacterial growth was dependent on both the energy and the complex nitrogen source. Bacteriocin production was growth associated, with a simultaneous bacteriocin adsorption on the producer cells dependent on the lactic acid accumulated and hence the viability of the cells. Both bacteriocin production and adsorption were inhibited by high concentrations of the complex nitrogen source. PMID:10653724

  5. Fed-Batch Control and Visualization of Monomer Sequences of Individual ICAR ATRP Gradient Copolymer Chains

    Directory of Open Access Journals (Sweden)

    Dagmar R. D'hooge

    2014-04-01

    Full Text Available Based on kinetic Monte Carlo simulations of the monomer sequences of a representative number of copolymer chains (≈ 150,000, optimal synthesis procedures for linear gradient copolymers are proposed, using bulk Initiators for Continuous Activator Regeneration Atom Transfer Radical Polymerization (ICAR ATRP. Methyl methacrylate and n-butyl acrylate are considered as comonomers with CuBr2/PMDETA (N,N,N′,N′′,N′′-pentamethyldiethylenetriamine as deactivator at 80 °C. The linear gradient quality is determined in silico using the recently introduced gradient deviation ( polymer property. Careful selection or fed-batch addition of the conventional radical initiator I2 allows a reduction of the polymerization time with ca. a factor 2 compared to the corresponding batch case, while preserving control over polymer properties ( ≈ 0.30; dispersity ≈ 1.1. Fed-batch addition of not only I2, but also comonomer and deactivator (50 ppm under starved conditions yields a below 0.25 and, hence, an excellent linear gradient quality for the dormant polymer molecules, albeit at the expense of an increase of the overall polymerization time. The excellent control is confirmed by the visualization of the monomer sequences of ca. 1000 copolymer chains.

  6. Concentrated fed-batch cell culture increases manufacturing capacity without additional volumetric capacity.

    Science.gov (United States)

    Yang, William C; Minkler, Daniel F; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2016-01-10

    Biomanufacturing factories of the future are transitioning from large, single-product facilities toward smaller, multi-product, flexible facilities. Flexible capacity allows companies to adapt to ever-changing pipeline and market demands. Concentrated fed-batch (CFB) cell culture enables flexible manufacturing capacity with limited volumetric capacity; it intensifies cell culture titers such that the output of a smaller facility can rival that of a larger facility. We tested this hypothesis at bench scale by developing a feeding strategy for CFB and applying it to two cell lines. CFB improved cell line A output by 105% and cell line B output by 70% compared to traditional fed-batch (TFB) processes. CFB did not greatly change cell line A product quality, but it improved cell line B charge heterogeneity, suggesting that CFB has both process and product quality benefits. We projected CFB output gains in the context of a 2000-L small-scale facility, but the output was lower than that of a 15,000-L large-scale TFB facility. CFB's high cell mass also complicated operations, eroded volumetric productivity, and showed our current processes require significant improvements in specific productivity in order to realize their full potential and savings in manufacturing. Thus, improving specific productivity can resolve CFB's cost, scale-up, and operability challenges. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Production of nattokinase by batch and fed-batch culture of Bacillus subtilis.

    Science.gov (United States)

    Cho, Young-Han; Song, Jae Yong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Sang Bum; Kim, Hyeon Shup; Han, Nam Soo; Lee, Bong Hee; Kim, Beom Soo

    2010-09-30

    Nattokinase was produced by batch and fed-batch culture of Bacillus subtilis in flask and fermentor. Effect of supplementing complex media (peptone, yeast extract, or tryptone) was investigated on the production of nattokinase. In flask culture, the highest cell growth and nattokinase activity were obtained with 50 g/L of peptone supplementation. In this condition, nattokinase activity was 630 unit/ml at 12 h. In batch culture of B. subtilis in fermentor, the highest nattokinase activity of 3400 unit/ml was obtained at 10h with 50 g/L of peptone supplementation. From the batch kinetics data, it was shown that nattokinase production was growth-associated and culture should be harvested before stationary phase for maximum nattokinase production. In fed-batch culture of B. subtilis using pH-stat feeding strategy, cell growth (optical density monitored at 600 nm) increased to ca. 100 at 22 h, which was 2.5 times higher than that in batch culture. The highest nattokinase activity was 7100 unit/ml at 19 h, which was also 2.1 times higher than that in batch culture. Copyright 2010 Elsevier B.V. All rights reserved.

  8. Nisin production of Lactococcus lactis N8 with hemin-stimulated cell respiration in fed-batch fermentation system.

    Science.gov (United States)

    Kördikanlıoğlu, Burcu; Şimşek, Ömer; Saris, Per E J

    2015-01-01

    In this study, nisin production of Lactococcus lactis N8 was optimized by independent variables of glucose, hemin and oxygen concentrations in fed-batch fermentation in which respiration of cells was stimulated with hemin. Response surface model was able to explain the changes of the nisin production of L. lactis N8 in fed-batch fermentation system with high fidelity (R(2) 98%) and insignificant lack of fit. Accordingly, the equation developed indicated the optimum parameters for glucose, hemin, and dissolved oxygen were 8 g L(-1) h(-1) , 3 μg mL(-1) and 40%, respectively. While 1711 IU mL(-1) nisin was produced by L. lactis N8 in control fed-batch fermentation, 5410 IU mL(-1) nisin production was achieved within the relevant optimum parameters where the respiration of cell was stimulated with hemin. Accordingly, nisin production was enhanced 3.1 fold in fed-batch fermentation using hemin. In conclusion the nisin production of L. lactis N8 was enhanced extensively as a result of increasing the biomass by stimulating the cell respiration with adding the hemin in the fed-batch fermentation. © 2015 American Institute of Chemical Engineers.

  9. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Directory of Open Access Journals (Sweden)

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  10. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Science.gov (United States)

    2012-01-01

    Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v) and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates. PMID:22433563

  11. Functional State Modelling of Cultivation Processes: Dissolved Oxygen Limitation State

    Directory of Open Access Journals (Sweden)

    Olympia Roeva

    2015-04-01

    Full Text Available A new functional state, namely dissolved oxygen limitation state for both bacteria Escherichia coli and yeast Saccharomyces cerevisiae fed-batch cultivation processes is presented in this study. Functional state modelling approach is applied to cultivation processes in order to overcome the main disadvantages of using global process model, namely complex model structure and a big number of model parameters. Alongwith the newly introduced dissolved oxygen limitation state, second acetate production state and first acetate production state are recognized during the fed-batch cultivation of E. coli, while mixed oxidative state and first ethanol production state are recognized during the fed-batch cultivation of S. cerevisiae. For all mentioned above functional states both structural and parameter identification is here performed based on experimental data of E. coli and S. cerevisiae fed-batch cultivations.

  12. 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.

  13. 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

    optimization, especially media optimization. Gaining knowledge on their interrelations could provide insight for obtaining higher immunoglobulin G (IgG) titer and better controlling glycosylationrelated product quality. In this work, different fed-batch processes with two chemically defined proprietary media......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...... and glutamine concentrations and uptake rates were positively correlated with intracellular UDP-Gal availability. All these findings are important for optimization of fed-batch culture for improving IgG production and directing glycosylation quality....

  14. Advanced control of dissolved oxygen concentration in fed batch cultures during recombinant protein production.

    Science.gov (United States)

    Kuprijanov, A; Gnoth, S; Simutis, R; Lübbert, A

    2009-02-01

    Design and experimental validation of advanced pO(2) controllers for fermentation processes operated in the fed-batch mode are described. In most situations, the presented controllers are able to keep the pO(2) in fermentations for recombinant protein productions exactly on the desired value. The controllers are based on the gain-scheduling approach to parameter-adaptive proportional-integral controllers. In order to cope with the most often appearing distortions, the basic gain-scheduling feedback controller was complemented with a feedforward control component. This feedforward/feedback controller significantly improved pO(2) control. By means of numerical simulations, the controller behavior was tested and its parameters were determined. Validation runs were performed with three Escherichia coli strains producing different recombinant proteins. It is finally shown that the new controller leads to significant improvements in the signal-to-noise ratio of other key process variables and, thus, to a higher process quality.

  15. Fed-batch production of hydrophobin RodB from Aspergillus fumigatus in host Pichia pastoris

    DEFF Research Database (Denmark)

    Pedersen, Mona Højgaard; Borodina, Irina; Frisvad, Jens Christian

    was dependent on the methanol-induced AOX1 promoter. Later production was scaled up to a 2 L fed-batch fermentor. Protein production was analyzed by SDS-PAGE, coomassie and silver-stained, as well as western blotting using an anti-his detection antibody. RodB was purified using His-select Nickel Affinity gel....... The emulsifying property of rRodB was investigated using olive oil stained with Sudan black suspended in tris-buffer. The stability of oil micelles were studied by light microscopy. Results: Protein bands of expected size were detected by SDS-PAGE and western blotting in both the fermentation broth and excess...

  16. A Genetic Algorithm for Feeding Trajectory Optimisation of Fed-batch Fermentation Processes

    Directory of Open Access Journals (Sweden)

    Stoyan Tzonkov

    2009-03-01

    Full Text Available In this work a genetic algorithm is proposed with the purpose of the feeding trajectory optimization during a fed-batch fermentation of E. coli. The feed rate profiles are evaluated based on a number of objective functions. Optimization results obtained for different feeding trajectories demonstrate that the genetic algorithm works well and shows good computational performance. Developed optimal feed profiles meet the defined criteria. The ration of the substrate concentration and the difference between actual cell concentration and theoretical maximum cell concentration is defined as the most appropriate objective function. In this case the final cell concentration of 43 g·l-1 and final product concentration of 125 g·l-1 are achieved and there is not significant excess of substrate.

  17. Alcoholic fermentation with flocculant Saccharomyces cerevisiae in fed-batch process.

    Science.gov (United States)

    Guidini, Carla Zanella; Marquez, Líbia Diniz Santos; de Almeida Silva, Helisângela; de Resende, Miriam Maria; Cardoso, Vicelma Luiz; Ribeiro, Eloízio Júlio

    2014-02-01

    Studies have been conducted on selecting yeast strains for use in fermentation for ethanol production to improve the performance of industrial plants and decrease production costs. In this paper, we study alcoholic fermentation in a fed-batch process using a Saccharomyces cerevisiae yeast strain with flocculant characteristics. Central composite design (CCD) was used to determine the optimal combination of the variables involved, with the sucrose concentration of 170 g/L, a cellular concentration in the inoculum of 40% (v/v), and a filling time of 6 h, which resulted in a 92.20% yield relative to the theoretical maximum yield, a productivity of 6.01 g/L h and a residual sucrose concentration of 44.33 g/L. With some changes in the process such as recirculation of medium during the fermentation process and increase in cellular concentration in the inoculum after use of the CCD was possible to reduce the residual sucrose concentration to 2.8 g/L in 9 h of fermentation and increase yield and productivity for 92.75% and 9.26 g/L h, respectively. A model was developed to describe the inhibition of alcoholic fermentation kinetics by the substrate and the product. The maximum specific growth rate was 0.103 h(-1), with K(I) and K(s) values of 109.86 and 30.24 g/L, respectively. The experimental results from the fed-batch reactor show a good fit with the proposed model, resulting in a maximum growth rate of 0.080 h(-1).

  18. Extracellular carbohydrate metabolites from Streptomyces coelicolor A3(2)

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, Stanislav; Sedmera, Petr; Halada, Petr; Petříček, Miroslav

    2007-01-01

    Roč. 70, - (2007), s. 768-771 ISSN 0163-3864 R&D Projects: GA ČR GA310/03/0285 Institutional research plan: CEZ:AV0Z50200510 Keywords : streptomyces coelicolor * cultivation * spectroscopic Subject RIV: EE - Microbiology, Virology Impact factor: 2.551, year: 2007

  19. 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

  20. 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.

  1. A novel model-based control strategy for aerobic filamentous fungal fed-batch fermentation processes.

    Science.gov (United States)

    Mears, Lisa; Stocks, Stuart M; Albaek, Mads O; Cassells, Benny; Sin, Gürkan; Gernaey, Krist V

    2017-07-01

    A novel model-based control strategy has been developed for filamentous fungal fed-batch fermentation processes. The system of interest is a pilot scale (550 L) filamentous fungus process operating at Novozymes A/S. In such processes, it is desirable to maximize the total product achieved in a batch in a defined process time. In order to achieve this goal, it is important to maximize both the product concentration, and also the total final mass in the fed-batch system. To this end, we describe the development of a control strategy which aims to achieve maximum tank fill, while avoiding oxygen limited conditions. This requires a two stage approach: (i) calculation of the tank start fill; and (ii) on-line control in order to maximize fill subject to oxygen transfer limitations. First, a mechanistic model was applied off-line in order to determine the appropriate start fill for processes with four different sets of process operating conditions for the stirrer speed, headspace pressure, and aeration rate. The start fills were tested with eight pilot scale experiments using a reference process operation. An on-line control strategy was then developed, utilizing the mechanistic model which is recursively updated using on-line measurements. The model was applied in order to predict the current system states, including the biomass concentration, and to simulate the expected future trajectory of the system until a specified end time. In this way, the desired feed rate is updated along the progress of the batch taking into account the oxygen mass transfer conditions and the expected future trajectory of the mass. The final results show that the target fill was achieved to within 5% under the maximum fill when tested using eight pilot scale batches, and over filling was avoided. The results were reproducible, unlike the reference experiments which show over 10% variation in the final tank fill, and this also includes over filling. The variance of the final tank fill is

  2. The development of an industrial-scale fed-batch fermentation simulation.

    Science.gov (United States)

    Goldrick, Stephen; Ştefan, Andrei; Lovett, David; Montague, Gary; Lennox, Barry

    2015-01-10

    This paper describes a simulation of an industrial-scale fed-batch fermentation that can be used as a benchmark in process systems analysis and control studies. The simulation was developed using a mechanistic model and validated using historical data collected from an industrial-scale penicillin fermentation process. Each batch was carried out in a 100,000 L bioreactor that used an industrial strain of Penicillium chrysogenum. The manipulated variables recorded during each batch were used as inputs to the simulator and the predicted outputs were then compared with the on-line and off-line measurements recorded in the real process. The simulator adapted a previously published structured model to describe the penicillin fermentation and extended it to include the main environmental effects of dissolved oxygen, viscosity, temperature, pH and dissolved carbon dioxide. In addition the effects of nitrogen and phenylacetic acid concentrations on the biomass and penicillin production rates were also included. The simulated model predictions of all the on-line and off-line process measurements, including the off-gas analysis, were in good agreement with the batch records. The simulator and industrial process data are available to download at www.industrialpenicillinsimulation.com and can be used to evaluate, study and improve on the current control strategy implemented on this facility. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

  3. Fed batch fermentation scale up in the production of recombinant streptokinase

    Directory of Open Access Journals (Sweden)

    Salvador Losada-Nerey

    2017-01-01

    Full Text Available Due to the high international demand of the recombinant streptokinase (Skr produced at the National Center for Bioproducts (BioCen, it was necessary to increase the production capacity of the drug, since the current production volume does not cover the demand. A scale up of the process of fermentation of the recombinant streptokinase was made using a fed batch culture, from the bank scale towards a 300L fermenter. The scaling criteria used were: the intensive variables of the process, the relationships of volumes of the fermentation medium and inoculum, the volumetric coefficient of oxygen transfer and air volume to liquid flow relationship which were kept constant. With this scale up procedure it was possible to reproduce the results obtained at the bank scale of and to double the biomass production volume with the same equipment, fulfilling all the quality requirements of the product and to cover the current demand of the market. Techno-economic indicators demonstrated the feasibility of this option.

  4. 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.

  5. Fed-Batch Production of Bacterial Ghosts Using Dielectric Spectroscopy for Dynamic Process Control

    Directory of Open Access Journals (Sweden)

    Andrea Meitz

    2016-03-01

    Full Text Available The Bacterial Ghost (BG platform technology evolved from a microbiological expression system incorporating the ϕX174 lysis gene E. E-lysis generates empty but structurally intact cell envelopes (BGs from Gram-negative bacteria which have been suggested as candidate vaccines, immunotherapeutic agents or drug delivery vehicles. E-lysis is a highly dynamic and complex biological process that puts exceptional demands towards process understanding and control. The development of a both economic and robust fed-batch production process for BGs required a toolset capable of dealing with rapidly changing concentrations of viable biomass during the E-lysis phase. This challenge was addressed using a transfer function combining dielectric spectroscopy and soft-sensor based biomass estimation for monitoring the rapid decline of viable biomass during the E-lysis phase. The transfer function was implemented to a feed-controller, which followed the permittivity signal closely and was capable of maintaining a constant specific substrate uptake rate during lysis phase. With the described toolset, we were able to increase the yield of BG production processes by a factor of 8–10 when compared to currently used batch procedures reaching lysis efficiencies >98%. This provides elevated potentials for commercial application of the Bacterial Ghost platform technology.

  6. The digester modification for biogas production from palm oil mill effluent by Fed-batch

    Science.gov (United States)

    Aznury, M.; Amin, J. M.; Hasan, A.; Harsyah, A.

    2018-03-01

    The purpose of this research is to biogas production in the digester modification equipment by Fed-batch of the palm oil mill effluent (POME) to determine the quality of POME after a treatment and the concentration of biogas that is formed every 24 hours within 10 days. The raw materials used are POME from PT Mitra Ogan, Tbk. In the initial stage is sedimentation process in the first digester tank at a flow rate 6 liters/minute and then observing the retention time of 24 hours. POME flowed into the second digester tank for fermentation process with the addition of active microbes seed every 24 hours to produce biogas. After the fermentation process is complete, POME flowed to third digester tank for water treatment stage before being released into the environment. COD content test values obtained after processing are 766, 362 and 350 mg/L, approximately. While the BOD value is 212.75; 125 and 110.9 mg/L, approximately. Biogas production for 10 days fermentation are 10.88% methane, 19.2% oxygen and 75.83% nitrogen, approximately.

  7. THE EFFECT OF THE ADDITION OF INVERT SUGAR ON THE PRODUCTION OF CEPHALOSPORIN C IN A FED-BATCH BIOREACTOR

    Directory of Open Access Journals (Sweden)

    A.S. Silva

    1998-12-01

    Full Text Available Cephalosporin C, a b -lactam antibiotic, is the starting molecule for industrial production of semi-synthetic cephalosporins. The bioprocess for its production is carried out in batch stirred and aerated tank reactors utilizing strains of the filamentous fungus Cephalosporium acremonium. In this work a comparison was made between the processes of production of cephalosporin C in a conventional batch bioreactor, with synthetic medium containing glucose and sucrose, and in a fed-batch reactor at several flowrates of supplementary medium containing invert sucrose. In general, the fed-batch process was shown to be more efficient than the conventional batch one, and the process in which the lowest supplementation flowrate was used presented an antibiotic production significantly higher than those obtained under the other conditions.

  8. High-concentration sugars production from corn stover based on combined pretreatments and fed-batch process.

    Science.gov (United States)

    Yang, Maohua; Li, Wangliang; Liu, Binbin; Li, Qiang; Xing, Jianmin

    2010-07-01

    In this paper, high-concentration sugars were produced from pretreated corn stover. The raw corn stover was pretreated in a process combining steam explosion and alkaline hydrogen-peroxide. The hemicellulose and lignin were removed greatly. The cellulose content increased to 73.2%. Fed-batch enzymatic hydrolysis was initiated with 12% (w/v) solids loading and 20 FPU/g solids. Then, 6% solids were fed consecutively at 12, 36 and 60 h. After 144 h, the final concentrations of reducing sugar, glucose, cellobiose and xylose reached 220, 175, 22 and 20 g/L, respectively. The final total biomass conversion was 60% in fed-batch process. Copyright 2009 Elsevier Ltd. All rights reserved.

  9. Optimization of fed-batch enzymatic hydrolysis from alkali-pretreated sugarcane bagasse for high-concentration sugar production.

    Science.gov (United States)

    Gao, Yueshu; Xu, Jingliang; Yuan, Zhenhong; Zhang, Yu; Liu, Yunyun; Liang, Cuiyi

    2014-09-01

    Fed-batch enzymatic hydrolysis process from alkali-pretreated sugarcane bagasse was investigated to increase solids loading, produce high-concentration fermentable sugar and finally to reduce the cost of the production process. The optimal initial solids loading, feeding time and quantities were examined. The hydrolysis system was initiated with 12% (w/v) solids loading in flasks, where 7% fresh solids were fed consecutively at 6h, 12h, 24h to get a final solids loading of 33%. All the requested cellulase loading (10 FPU/g substrate) was added completely at the beginning of hydrolysis reaction. After 120 h of hydrolysis, the maximal concentrations of cellobiose, glucose and xylose obtained were 9.376 g/L, 129.50 g/L, 56.03 g/L, respectively. The final total glucan conversion rate attained to 60% from this fed-batch process. Copyright © 2014. Published by Elsevier Ltd.

  10. Fed-batch culture for the direct conversion of cellulosic substrates to acetic acid/ethanol by Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P.K.R.; Singh, A.; Schuegerl, K. (Hannover Univ. (Germany). Inst. fuer Technische Chemie)

    1991-01-01

    The production of acetic acid/ethanol and hydrolytic enzymes from potato waste (cellulosic waste from potato starch industries) by Fusarium oxysporum 841 was improved considerably by using fed-batch culture. In this, two types of feed policies were adopted consisting of different substrate concentrations and feeding times. In fed-batch culture, the enzymes tested, namely avicelase, CMCase, cellobiase and xylanase, showed significant improvements over batch fermentations with regard to enzyme titres and productivities. The maximum concentration, yield and productivity of acetic acid were 22.5 g litre{sup -1}, 0.38 g (g {sub strate}){sup -1} and 0.09 g litre{sup -1} h{sup -1}, respectively, and these values for ethanol were 5.7 g litre{sup -1}, 0.1 g (g substrate){sup -1} and 0.03 g litre{sup -1}h{sup -1}, respectively. (author).

  11. COMPARISON OF VACUUM AND HIGH PRESSURE EVAPORATED WOOD HYDROLYZATE FOR ETHANOL PRODUCTION BY REPEATED FED-BATCH USING FLOCCULATING SACCHAROMYCES CEREVISIAE

    Directory of Open Access Journals (Sweden)

    Anahita Dehkhoda

    2009-02-01

    Full Text Available With the aim of increasing the sugars concentration in dilute-acid ligno-cellulosic hydrolyzate to more than 100 g/l for industrial applications, the hydrolyzate from spruce was concentrated about threefold by high-pressure or vacuum evaporations. It was then fermented by repeated fed-batch cultivation using flocculating Saccharomyces cerevisiae with no prior detoxification. The sugars and inhibitors concentrations in the hydrolyzates were compared after the evaporations and also fermenta-tion. The evaporations were carried out either under vacuum (VEH at 0.5 bar and 80°C or with 1.3 bar pressure (HPEH at 107.5°C, which resulted in 153.3 and 164.6 g/l total sugars, respectively. No sugar decomposition occurred during either of the evaporations, while more than 96% of furfural and to a lesser extent formic and acetic acids disappeared from the hydrolyzates. However, HMF and levulinic acid remained in the hydrolyzates and were concentrated proportionally. The concentrated hydrolyzates were then fermented in a 4 l bioreactor with 12-22 g/l yeast and 0.14-0.22 h-1 initial dilute rates (ID. More than 84% of the fermentable sugars present in the VEH were fermented by fed-batch cultivation using 12 g/l yeast and initial dilution rate (ID of 0.22 h-1, and resulted in 0.40±0.01 g/g ethanol from the fermentable sugars in one cycle of fermentation. Fermentation of HPEH was as successful as VEH and resulted in more than 86% of the sugar consumption under the corresponding conditions. By lowering the initial dilution rate to 0.14 h-1, more than 97% of the total fermentable sugars were consumed, and ethanol yield was 0.44±0.01 g/g in one cycle of fermentation. The yeast was able to convert or assimilate HMF, levulinic, acetic, and formic acids by 96, 30, 43, and 74%, respectively.

  12. A parametric study ot protease production in batch and fed-batch cultures of Bacillus firmus.

    Science.gov (United States)

    Moon, S H; Parulekar, S J

    1991-03-05

    Proteolytic enzymes produced by Bacillus species find a wide variety of applications in brewing, detergent, food, and leather industries. Owing to significant differences normally observed in culture conditions promoting cell growth and those promoting production of metabolites such as enzymes, for increased efficacy of bioreactor operations it is essential to identify these sets of conditions (including medium formulation). This study is focused on formulation of a semidefined medium that substantially enhances synthesis and secretion of an alkaline protease in batch cultures of Bacillus firmus NRS 783, a known superior producer of this enzyme. The series of experiments conducted to identify culture conditions that lead to improved protease production also enables investigation of the regulatory effects of important culture parameters including pH, dissolved oxygen, and concentrations of nitrogen and phosphorous sources and yeast extract in the medium on cell growth, synthesis and secretion of protease, and production of two major nonbiomass products, viz., acetic acid and ethanol. Cell growth and formation of the three nonbiomass products are hampered significantly under nitrogen, phosphorous, or oxygen limitation, with the cells being unable to grow in an oxygen-free environment. Improvement in protease production is achieved with respect to each culture parameter, leading in the process to 80% enhancement in protease activity over that attained using media reported in the literature. Results of a few fed-batch experiments with constant feed rate, conducted to examine possible enhancement in protease production and to further investigate repression of protease synthesis by excess of the principal carbon and nitrogen sources, are also discussed. The detailed investigation of stimulatory and repressory effects of simple and complex nutrients on protease production and metabolism of Bacillus firmus conducted in this study will provide useful guidelines for design

  13. Continuous citric acid production in repeated-fed batch fermentation by Aspergillus niger immobilized on a new porous foam.

    Science.gov (United States)

    Yu, Bin; Zhang, Xin; Sun, Wenjun; Xi, Xun; Zhao, Nan; Huang, Zichun; Ying, Zhuojun; Liu, Li; Liu, Dong; Niu, Huanqing; Wu, Jinglan; Zhuang, Wei; Zhu, Chenjie; Chen, Yong; Ying, Hanjie

    2018-03-24

    The efficiency of current methods for industrial production of citric acid is limited. To achieve continuous citric acid production with enhanced yield and reduced cost, immobilized fermentation was employed in an Aspergillus niger 831 repeated fed-batch fermentation system. We developed a new type of material (PAF201), which was used as a carrier for the novel adsorption immobilization system. Hydrophobicity, pore size and concentration of carriers were researched in A. niger immobilization. The efficiency of the A. niger immobilization process was analyzed by scanning electron microscopy. Then eight-cycle repeated fed-batch cultures for citric acid production were carried out over 600 h, which showed stable production with maximum citric acid concentrations and productivity levels of 162.7 g/L and 2.26 g L -1  h -1 , respectively. Compared with some other literatures about citric acid yield, PAF201 immobilization system is 11.3% higher than previous results. These results indicated that use of the new adsorption immobilization system could greatly improve citric acid productivity in repeated fed-batch fermentation. Moreover, these results could provide a guideline for A.niger or other filamentous fungi immobilization in industry. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Modeling of Fusarium redolens Dzf2 mycelial growth kinetics and optimal fed-batch fermentation for beauvericin production.

    Science.gov (United States)

    Xu, Li-Jian; Liu, Yuan-Shuai; Zhou, Li-Gang; Wu, Jian-Yong

    2011-09-01

    Beauvericin (BEA) is a cyclic hexadepsipeptide mycotoxin with notable phytotoxic and insecticidal activities. Fusarium redolens Dzf2 is a highly BEA-producing fungus isolated from a medicinal plant. The aim of the current study was to develop a simple and valid kinetic model for F. redolens Dzf2 mycelial growth and the optimal fed-batch operation for efficient BEA production. A modified Monod model with substrate (glucose) and product (BEA) inhibition was constructed based on the culture characteristics of F. redolens Dzf2 mycelia in a liquid medium. Model parameters were derived by simulation of the experimental data from batch culture. The model fitted closely with the experimental data over 20-50 g l(-1) glucose concentration range in batch fermentation. The kinetic model together with the stoichiometric relationships for biomass, substrate and product was applied to predict the optimal feeding scheme for fed-batch fermentation, leading to 54% higher BEA yield (299 mg l(-1)) than in the batch culture (194 mg l(-1)). The modified Monod model incorporating substrate and product inhibition was proven adequate for describing the growth kinetics of F. redolens Dzf2 mycelial culture at suitable but not excessive initial glucose levels in batch and fed-batch cultures.

  15. The use of date waste for lactic acid production by a fed-batch culture using Lactobacillus casei subsp. rhamnosus.

    Science.gov (United States)

    Nancib, Aicha; Nancib, Nabil; Boubendir, Abdelhafid; Boudrant, Joseph

    2015-01-01

    The production of lactic acid from date juice by Lactobacillus caseisubsp. rhamnosus in batch and fed-batch cultures has been investigated. The fed-batch culture system gave better results for lactic acid production and volumetric productivity. The aim of this work is to determine the effects of the feeding rate and the concentration of the feeding medium containing date juice glucose on the cell growth, the consumption of glucose and the lactic acid production by Lactobacillus casei subsp. rhamnosus in fed-batch cultures. For this study, two concentrations of the feeding medium (62 and 100 g/L of date juice glucose) were tested at different feeding rates (18, 22, 33, 75 and 150 mL/h). The highest volumetric productivity (1.3 g/L.h) and lactic acid yield (1.7 g/g) were obtained at a feeding rate of 33 mL/h and a date juice glucose concentration of 62 g/L in the feeding medium. As a result, most of the date juice glucose was completely utilised (residual glucose 1 g/L), and a maximum lactic acid production level (89.2 g/L) was obtained.

  16. Production of biomass and polysaccharides of Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt. :Fr.) P. Karst. (higher Basidiomycetes), by submerged cultivation.

    Science.gov (United States)

    Habijanic, Jozica; Berovic, Marin; Boh, Bojana; Wraber, Branka; Petravic-Tominac, Vlatka

    2013-01-01

    Submerged batch and repeated fed-batch cultivation techniques were used for mycelia cultivation and polysaccharide production of the Lingzhi or Reishi medicinal mushroom Ganoderma lucidum. Although most publications use various Asiatic G. lucidum strains, the growth of the strain Ga.l 4 (Biotechnical Faculty Strain Collection, Ljubljana, Slovenia), originally isolated from the Slovenian forest, is much faster. The results between the batch and repeated fed-batch cultivation are compared with the polysaccharide production in batch cultivation. From the aspect of biomass production, the best results were obtained in repeated fed-batch after 44 days, where 12.4 g/L of dry fungal biomass was obtained.

  17. Physiological changes of Candida tropicalis population degrading phenol in fed batch reactor

    Directory of Open Access Journals (Sweden)

    Eliska Komarkova

    2003-12-01

    Full Text Available Candida tropicalis can use phenol as the sole carbon and energy source. Experiments regarding phenol degradations from the water phase were carried out. The fermentor was operated as a fed-batch system with oxistat control. Under conditions of nutrient limitation and an excess of oxygen the respiration activity of cells was suppressed and some color metabolites (black-brown started to be formed. An accumulation of these products inhibited the cell growth under aerobic conditions. Another impact was a decrease of the phenol hydroxylase activity as the key enzyme of the phenol degradation pathway at the end of the cell respiration activity. This decrease is linked with the above mentioned product inhibition. The cell death studied by fluorescent probe proceeded very slowly after the loss of the respiration activity. The starvation stress induced an increase of the endogenous respiration rate at the expense of phenol oxidation.Candida tropicalis pode utilizar fenol como única fonte de carbono e de energia. O fermentador foi operado em um sistema ''batelada-alimentada'' e controle oxidativo. Em condições limitantes de nutrientes e excesso de oxigênio a atividade respiratória das células foi suprimida e o calor do metabolismo pode ser formado. Uma acumulação desses produtos inibiu o crescimento das células em condições aeróbicas. Outro impacto foi um decréscimo da atividade fenol hidroxilase como enzima chave da degradação do fenol no final da atividade respirométrica. Essa redução está relacionada com os fatos acima mencionados. A morte da célula estudada por sonda de fluorescência ocorreu lentamente após a perda da atividade respiratória. O ''stress'' celular induziu um aumento na taxa de respiração endógena devido à oxidação fenólica.

  18. Comparing a Dynamic Fed-Batch and a Continuous Steady-State Simulation of Ethanol Fermentation in a Distillery to a Stoichiometric Conversion Simulation

    OpenAIRE

    Fonseca, G.C.; Costa, C.B.B.; Cruz, A.J.G.

    2017-01-01

    Abstract An autonomous sugarcane bioethanol plant was simulated in EMSO software, an equation oriented process simulator. Three types of fermentation units were simulated: a six parallel fed-batch reactor system, a set of four CSTR in steady state and one consisting of a single stoichiometric reactor. Stoichiometric models are less accurate than kinetic-based fermentation models used for fed-batch and continuous fermenter simulations, since they do not account for inhibition effects and depen...

  19. Improved fed-batch production of high-purity PHB (poly-3 hydroxy butyrate) by Cupriavidus necator (MTCC 1472) from sucrose-based cheap substrates under response surface-optimized conditions.

    Science.gov (United States)

    Dey, Pinaki; Rangarajan, Vivek

    2017-10-01

    Experimental investigations were carried out for Cupriavidus necator (MTCC 1472)-based improved production of poly-3 hydroxy butyrate (PHB) through induced nitrogen limiting fed-batch cultivation strategies. Initially Plackett-Burman design and response surface methodology were implemented to optimize most influencing process parameters. With optimized process parameter values, continuous feeding strategies ware applied in a 5-l fermenter with table sugar concentration of 100 g/l, nitrogen concentration of 0.12 g/l for fed-batch fermentation with varying dilution rates of 0.02 and 0.046 1/h. To get enriched production of PHB, concentration of the sugar was further increased to 150 and 200 g/l in feeding. Maximum concentrations of PHB achieved were 22.35 and 23.07 g/l at those dilution rates when sugar concentration maintains at 200 g/l in feeding. At maximum concentration of PHB (23.07 g/l), productivity of 0.58 g/l h was achieved with maximum PHB accumulation efficiency up to 64% of the dry weight of biomass. High purity of PHB, close to medical grade was achieved after surfactant hypochlorite extraction method, and it was further confirmed by SEM, EDX, and XRD studies.

  20. Enhanced recombinant factor VII expression in Chinese hamster ovary cells by optimizing signal peptides and fed-batch medium.

    Science.gov (United States)

    Peng, Lin; Yu, Xiao; Li, Chengyuan; Cai, Yanfei; Chen, Yun; He, Yang; Yang, Jianfeng; Jin, Jian; Li, Huazhong

    2016-04-01

    Signal peptides play an important role in directing and efficiently transporting secretory proteins to their proper locations in the endoplasmic reticulum of mammalian cells. The aim of this study was to enhance the expression of recombinant coagulation factor VII (rFVII) in CHO cells by optimizing the signal peptides and type of fed-batch culture medium used. Five sub-clones (O2, I3, H3, G2 and M3) with different signal peptide were selected by western blot (WB) analysis and used for suspension culture. We compared rFVII expression levels of 5 sub-clones and found that the highest rFVII expression level was obtained with the IgK signal peptide instead of Ori, the native signal peptide of rFVII. The high protein expression of rFVII with signal peptide IgK was mirrored by a high transcription level during suspension culture. After analyzing culture and feed media, the combination of M4 and F4 media yielded the highest rFVII expression of 20 mg/L during a 10-day suspension culture. After analyzing cell density and cell cycle, CHO cells feeding by F4 had a similar percentage of cells in G0/G1 and a higher cell density compared to F2 and F3. This may be the reason for high rFVII expression in M4+F4. In summary, rFVII expression was successfully enhanced by optimizing the signal peptide and fed-batch medium used in CHO suspension culture. Our data may be used to improve the production of other therapeutic proteins in fed-batch culture.

  1. Comparative study of production of Bio-Indigo by Pandoraea sp. in a two phase - fed batch and continuous bioreactor

    Directory of Open Access Journals (Sweden)

    Vaishnavi Unde

    2016-03-01

    Full Text Available Indigo, is blue of blue jeans, a synthetic dye used on large scale all over the world. Chemical production of the dye is taking a new route towards bacterial production to overcome the environmental effects that are posed by the synthetic blue powder (Indigo. In the present work a strain Pandoraea sp. isolated from the oil contaminated soil is found to produce blue pigment which is analyzed qualitatively as indigo using UV-visible scan and Thin Layer Chromatography (TLC. The strain is used for indigo production at lab scale in two different bioreactor configurations first the fed batch mode and second continuous mode using two phases. The two phases consisting of medium carrying biomass and the second phase of silicone oil carrying substrate indole. The use of second phase allows higher concentration of substrate injection reducing the inhibition effects of the substrate as well as act as a partitioning agent for removal of the product. In two phase study, the maximum indigo produced was seen to be 0.068 g/L after 22 hours of substrate injection into the Fermentor in a fed batch mode. The maximum yield obtained in this configuration was 19%. For commercial production of bio-indigo a continuous operation is required, which was studied in a bioreactor with 2.5 liter capacity under the optimized conditions. The maximum indigo produced was found to be 0.052 g/L after about 72 hours of operation. The results showed decrease in the production of indigo in continuous mode as compared to fed batch operation, which may be due to the insufficient time available for the bacteria to bio-transform indole into indigo.

  2. Versatile modeling and optimization of fed batch processes for the production of secreted heterologous proteins with Pichia pastoris

    Directory of Open Access Journals (Sweden)

    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.

  3. Modelling of L-valine Repeated Fed-batch Fermentation Process Taking into Account the Dissolved Oxygen Tension

    Directory of Open Access Journals (Sweden)

    Tzanko Georgiev

    2009-03-01

    Full Text Available This article deals with synthesis of dynamic unstructured model of variable volume fed-batch fermentation process with intensive droppings for L-valine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates takes into account the dissolved oxygen tension; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  4. Production of pullulan by a thermotolerant Aureobasidium pullulans strain in non-stirred fed batch fermentation process

    OpenAIRE

    Singh, Ranjan; Gaur, Rajeeva; Tiwari, Soni; Gaur, Manogya Kumar

    2012-01-01

    Total 95 isolates of Aureobasidium pullulans were isolated from different flowers and leaves samples, out of which 11 thermotolerant strains produced pullulan. One thermotolerant non-melanin pullulan producing strain, designated as RG-5, produced highest pullulan (37.1±1.0 g/l) at 42ºC, pH 5.5 in 48h of incubation with 3% sucrose and 0.5% ammonium sulphate in a non-stirred fed batch fermentor of 6 liters capacity. The two liters of initial volume of fermentation medium was further fed with th...

  5. Butanol production from wheat straw by simultaneous saccharification and fermentation using Clostridium beijerinckii: Part II-Fed-batch fermentation

    International Nuclear Information System (INIS)

    Qureshi, Nasib; Saha, Badal C.; Cotta, Michael A.

    2008-01-01

    In these studies, Clostridium beijerinckii P260 was used to produce butanol (acetone-butanol-ethanol, or ABE) from wheat straw (WS) hydrolysate in a fed-batch reactor. It has been demonstrated that simultaneous hydrolysis of WS to achieve 100% hydrolysis to simple sugars (to the extent achievable under present conditions) and fermentation to butanol is possible. In addition to WS, the reactor was fed with a sugar solution containing glucose, xylose, arabinose, galactose, and mannose. The culture utilized all of the above sugars. It was noticed that near the end of fermentation (286-533 h), the culture had difficulties utilizing xylose. As a result of supplemental sugar feed to the reactor, ABE productivity was improved by 16% as compared with previous studies. In our previous experiment on simultaneous saccharification of WS and fermentation to butanol, a productivity of 0.31 g L -1 h -1 was observed, while in the present studies a productivity of 0.36 g L -1 h -1 was observed. It should be noted that a productivity of 0.77 g L -1 h -1 was observed when the culture was highly active. The fed-batch fermentation was operated for 533 h. It should be noted that C. beijerinckii P260 can be used to produce butanol from WS in integrated fermentations

  6. 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.

  7. Effects of the feeding ratio of food waste on fed-batch aerobic composting and its microbial community.

    Science.gov (United States)

    Wang, Xiaojun; Pan, Songqing; Zhang, Zhaoji; Lin, Xiangyu; Zhang, Yuzhen; Chen, Shaohua

    2017-01-01

    To determine the suitable feeding ratio for fed-batch aerobic composting, four fermenters were operated by adding 0%, 5%, 10% or 15% of food waste every day. The results showed that the 5% and 10% treatments were able to maintain continuous thermophilic conditions, while the 15% treatment performed badly in regard to composting temperature, which was probably due to the negative effects of excessive moisture on microbial activity. As composting proceeded, both the 5% and the 10% treatments reached maturity and achieved weight losses of approximately 65%. High-throughput sequencing results indicated that Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were the dominant phyla of the community structure. The communities sampled at the thermophilic phases had high similarity and relatively low diversity, while species diversity increased in the maturity phase. This study was devoted to optimizing the fed-batch composting process and assessing bacterial communities, both of which were supplied as a reference for practical application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. 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.

  9. Fed-batch production of green coconut hydrolysates for high-gravity second-generation bioethanol fermentation with cellulosic yeast.

    Science.gov (United States)

    Soares, Jimmy; Demeke, Mekonnen M; Van de Velde, Miet; Foulquié-Moreno, Maria R; Kerstens, Dorien; Sels, Bert F; Verplaetse, Alex; Fernandes, Antonio Alberto Ribeiro; Thevelein, Johan M; Fernandes, Patricia Machado Bueno

    2017-11-01

    The residual biomass obtained from the production of Cocos nucifera L. (coconut) is a potential source of feedstock for bioethanol production. Even though coconut hydrolysates for ethanol production have previously been obtained, high-solid loads to obtain high sugar and ethanol levels remain a challenge. We investigated the use of a fed-batch regime in the production of sugar-rich hydrolysates from the green coconut fruit and its mesocarp. Fermentation of the hydrolysates obtained from green coconut or its mesocarp, containing 8.4 and 9.7% (w/v) sugar, resulted in 3.8 and 4.3% (v/v) ethanol, respectively. However, green coconut hydrolysate showed a prolonged fermentation lag phase. The inhibitor profile suggested that fatty acids and acetic acid were the main fermentation inhibitors. Therefore, a fed-batch regime with mild alkaline pretreatment followed by saccharification, is presented as a strategy for fermentation of such challenging biomass hydrolysates, even though further improvement of yeast inhibitor tolerance is also needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Electrochemical study of multi-electrode microbial fuel cells under fed-batch and continuous flow conditions

    KAUST Repository

    Ren, Lijiao

    2014-07-01

    Power production of four hydraulically connected microbial fuel cells (MFCs) was compared with the reactors operated using individual electrical circuits (individual), and when four anodes were wired together and connected to four cathodes all wired together (combined), in fed-batch or continuous flow conditions. Power production under these different conditions could not be made based on a single resistance, but instead required polarization tests to assess individual performance relative to the combined MFCs. Based on the power curves, power produced by the combined MFCs (2.12 ± 0.03 mW, 200 ω) was the same as the summed power (2.13 mW, 50 ω) produced by the four individual reactors in fed-batch mode. With continuous flow through the four MFCs, the maximum power (0.59 ± 0.01 mW) produced by the combined MFCs was slightly lower than the summed maximum power of the four individual reactors (0.68 ± 0.02 mW). There was a small parasitic current flow from adjacent anodes and cathodes, but overall performance was relatively unaffected. These findings demonstrate that optimal power production by reactors hydraulically and electrically connected can be predicted from performance by individual reactors. © 2013 Elsevier B.V. All rights reserved.

  11. Kinetic model-based feed-forward controlled fed-batch fermentation of Lactobacillus rhamnosus for the production of lactic acid from Arabic date juice.

    Science.gov (United States)

    Choi, Minsung; Al-Zahrani, Saeed M; Lee, Sang Yup

    2014-06-01

    Arabic date is overproduced in Arabic countries such as Saudi Arabia and Iraq and is mostly composed of sugars (70-80 wt%). Here we developed a fed-batch fermentation process by using a kinetic model for the efficient production of lactic acid to a high concentration from Arabic date juice. First, a kinetic model of Lactobacillus rhamnosus grown on date juice in batch fermentation was constructed in EXCEL so that the estimation of parameters and simulation of the model can be easily performed. Then, several fed-batch fermentations were conducted by employing different feeding strategies including pulsed feeding, exponential feeding, and modified exponential feeding. Based on the results of fed-batch fermentations, the kinetic model for fed-batch fermentation was also developed. This new model was used to perform feed-forward controlled fed-batch fermentation, which resulted in the production of 171.79 g l(-1) of lactic acid with the productivity and yield of 1.58 and 0.87 g l(-1) h(-1), respectively.

  12. 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.

  13. Efficient soluble expression of disulfide bonded proteins in the cytoplasm of Escherichia coli in fed-batch fermentations on chemically defined minimal media.

    Science.gov (United States)

    Gąciarz, Anna; Khatri, Narendar Kumar; Velez-Suberbie, M Lourdes; Saaranen, Mirva J; Uchida, Yuko; Keshavarz-Moore, Eli; Ruddock, Lloyd W

    2017-06-15

    The production of recombinant proteins containing disulfide bonds in Escherichia coli is challenging. In most cases the protein of interest needs to be either targeted to the oxidizing periplasm or expressed in the cytoplasm in the form of inclusion bodies, then solubilized and re-folded in vitro. Both of these approaches have limitations. Previously we showed that soluble expression of disulfide bonded proteins in the cytoplasm of E. coli is possible at shake flask scale with a system, known as CyDisCo, which is based on co-expression of a protein of interest along with a sulfhydryl oxidase and a disulfide bond isomerase. With CyDisCo it is possible to produce disulfide bonded proteins in the presence of intact reducing pathways in the cytoplasm. Here we scaled up production of four disulfide bonded proteins to stirred tank bioreactors and achieved high cell densities and protein yields in glucose fed-batch fermentations, using an E. coli strain (BW25113) with the cytoplasmic reducing pathways intact. Even without process optimization production of purified human single chain IgA 1 antibody fragment reached 139 mg/L and hen avidin 71 mg/L, while purified yields of human growth hormone 1 and interleukin 6 were around 1 g/L. Preliminary results show that human growth hormone 1 was also efficiently produced in fermentations of W3110 strain and when glucose was replaced with glycerol as the carbon source. Our results show for the first time that efficient production of high yields of soluble disulfide bonded proteins in the cytoplasm of E. coli with the reducing pathways intact is feasible to scale-up to bioreactor cultivations on chemically defined minimal media.

  14. Comparing a Dynamic Fed-Batch and a Continuous Steady-State Simulation of Ethanol Fermentation in a Distillery to a Stoichiometric Conversion Simulation

    Directory of Open Access Journals (Sweden)

    G.C. Fonseca

    Full Text Available Abstract An autonomous sugarcane bioethanol plant was simulated in EMSO software, an equation oriented process simulator. Three types of fermentation units were simulated: a six parallel fed-batch reactor system, a set of four CSTR in steady state and one consisting of a single stoichiometric reactor. Stoichiometric models are less accurate than kinetic-based fermentation models used for fed-batch and continuous fermenter simulations, since they do not account for inhibition effects and depend on a known conversion rate of reactant to be specified instead. On the other hand, stoichiometric models are faster and simpler to converge. In this study it was found that the conversion rates of sugar for the fermentation systems analyzedwere predictable from information on the composition of the juice stream. Those rates were used in the stoichiometric model, which accurately reproduced the results from both the fed-batch and the continuous fermenter system.

  15. Ethanol production from Sorghum bicolor using both separate and simultaneous saccharification and fermentation in batch and fed batch systems

    DEFF Research Database (Denmark)

    Mehmood, Sajid; Gulfraz, M.; Rana, N. F.

    2009-01-01

    The objective of this work was to find the best combination of different experimental conditions during pre-treatment, enzymatic saccharification, detoxification of inhibitors and fermentation of Sorghum bicolor straw for ethanol production. The optimization of pre-treatment using different...... were used in order to increase the monomeric sugar during enzymatic hydrolysis and it has been observed that the addition of these surfactants contributed significantly in cellulosic conversion but no effect was shown on hemicellulosic hydrolysis. Fermentability of hydrolyzate was tested using...... Saccharomyces cerevisiae Ethanol Red (TM) and it was observed that simultaneous saccharification and fermentation ( SSF) with both batch and fed batch resulted in better ethanol yield as compared to separate hydrolysis and fermentation ( SHF). Detoxification of furan during SHF facilitated reduction...

  16. 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.

  17. Production of pullulan by a thermotolerant Aureobasidium pullulans strain in non-stirred fed batch fermentation process

    Directory of Open Access Journals (Sweden)

    Ranjan Singh

    2012-09-01

    Full Text Available Total 95 isolates of Aureobasidium pullulans were isolated from different flowers and leaves samples, out of which 11 thermotolerant strains produced pullulan. One thermotolerant non-melanin pullulan producing strain, designated as RG-5, produced highest pullulan (37.1±1.0 g/l at 42ºC, pH 5.5 in 48h of incubation with 3% sucrose and 0.5% ammonium sulphate in a non-stirred fed batch fermentor of 6 liters capacity. The two liters of initial volume of fermentation medium was further fed with the 2 liters in two successive batches at 5 h interval into the fermentor. The sterile air was supplied only for 10h at the rate of 0.5 vvm.

  18. Production of pullulan by a thermotolerant aureobasidium pullulans strain in non-stirred fed batch fermentation process.

    Science.gov (United States)

    Singh, Ranjan; Gaur, Rajeeva; Tiwari, Soni; Gaur, Manogya Kumar

    2012-07-01

    Total 95 isolates of Aureobasidium pullulans were isolated from different flowers and leaves samples, out of which 11 thermotolerant strains produced pullulan. One thermotolerant non-melanin pullulan producing strain, designated as RG-5, produced highest pullulan (37.1±1.0 g/l) at 42(o)C, pH 5.5 in 48h of incubation with 3% sucrose and 0.5% ammonium sulphate in a non-stirred fed batch fermentor of 6 liters capacity. The two liters of initial volume of fermentation medium was further fed with the 2 liters in two successive batches at 5 h interval into the fermentor. The sterile air was supplied only for 10h at the rate of 0.5 vvm.

  19. 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.

  20. Cybernetic modeling based on pathway analysis for Penicillium chrysogenum fed-batch fermentation.

    Science.gov (United States)

    Geng, Jun; Yuan, Jingqi

    2010-08-01

    A macrokinetic model employing cybernetic methodology is proposed to describe mycelium growth and penicillin production. Based on the primordial and complete metabolic network of Penicillium chrysogenum found in the literature, the modeling procedure is guided by metabolic flux analysis and cybernetic modeling framework. The abstracted cybernetic model describes the transients of the consumption rates of the substrates, the assimilation rates of intermediates, the biomass growth rate, as well as the penicillin formation rate. Combined with the bioreactor model, these reaction rates are linked with the most important state variables, i.e., mycelium, substrate and product concentrations. Simplex method is used to estimate the sensitive parameters of the model. Finally, validation of the model is carried out with 20 batches of industrial-scale penicillin cultivation.

  1. Batch and multi-step fed-batch enzymatic saccharification of Formiline-pretreated sugarcane bagasse at high solid loadings for high sugar and ethanol titers.

    Science.gov (United States)

    Zhao, Xuebing; Dong, Lei; Chen, Liang; Liu, Dehua

    2013-05-01

    Formiline pretreatment pertains to a biomass fractionation process. In the present work, Formiline-pretreated sugarcane bagasse was hydrolyzed with cellulases by batch and multi-step fed-batch processes at 20% solid loading. For wet pulp, after 144 h incubation with cellulase loading of 10 FPU/g dry solid, fed-batch process obtained ~150 g/L glucose and ~80% glucan conversion, while batch process obtained ~130 g/L glucose with corresponding ~70% glucan conversion. Solid loading could be further increased to 30% for the acetone-dried pulp. By fed-batch hydrolysis of the dried pulp in pH 4.8 buffer solution, glucose concentration could be 247.3±1.6 g/L with corresponding 86.1±0.6% glucan conversion. The enzymatic hydrolyzates could be well converted to ethanol by a subsequent fermentation using Saccharomices cerevisiae with ethanol titer of 60-70 g/L. Batch and fed-batch SSF indicated that Formiline-pretreated substrate showed excellent fermentability. The final ethanol concentration was 80 g/L with corresponding 82.7% of theoretical yield. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Parallel steady state studies on a milliliter scale accelerate fed-batch bioprocess design for recombinant protein production with Escherichia coli.

    Science.gov (United States)

    Schmideder, Andreas; Cremer, Johannes H; Weuster-Botz, Dirk

    2016-11-01

    In general, fed-batch processes are applied for recombinant protein production with Escherichia coli (E. coli). However, state of the art methods for identifying suitable reaction conditions suffer from severe drawbacks, i.e. direct transfer of process information from parallel batch studies is often defective and sequential fed-batch studies are time-consuming and cost-intensive. In this study, continuously operated stirred-tank reactors on a milliliter scale were applied to identify suitable reaction conditions for fed-batch processes. Isopropyl β-d-1-thiogalactopyranoside (IPTG) induction strategies were varied in parallel-operated stirred-tank bioreactors to study the effects on the continuous production of the recombinant protein photoactivatable mCherry (PAmCherry) with E. coli. Best-performing induction strategies were transferred from the continuous processes on a milliliter scale to liter scale fed-batch processes. Inducing recombinant protein expression by dynamically increasing the IPTG concentration to 100 µM led to an increase in the product concentration of 21% (8.4 g L -1 ) compared to an implemented high-performance production process with the most frequently applied induction strategy by a single addition of 1000 µM IPGT. Thus, identifying feasible reaction conditions for fed-batch processes in parallel continuous studies on a milliliter scale was shown to be a powerful, novel method to accelerate bioprocess design in a cost-reducing manner. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1426-1435, 2016. © 2016 American Institute of Chemical Engineers.

  3. 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.

  4. Fed-batch bioreactor performance and cell line stability evaluation of the artificial chromosome expression technology expressing an IgG1 in Chinese hamster ovary cells.

    Science.gov (United States)

    Combs, Rodney G; Yu, Erwin; Roe, Susanna; Piatchek, Michele Bailey; Jones, Heather L; Mott, John; Kennard, Malcolm L; Goosney, Danika L; Monteith, Diane

    2011-01-01

    The artificial chromosome expression (ACE) technology system uses an engineered artificial chromosome containing multiple site-specific recombination acceptor sites for the rapid and efficient construction of stable cell lines. The construction of Chinese hamster ovary(CHO) cell lines expressing an IgG1 monoclonal antibody (MAb) using the ACE system has been previously described (Kennard et al., Biotechnol Bioeng. 2009;104:540-553). To further demonstrate the manufacturing feasibility of the ACE system, four CHO cell lines expressing the human IgG1 MAb 4A1 were evaluated in batch and fed-batch shake flasks and in a 2-L fed-batch bioreactor. The batch shake flasks achieved titers between 0.7 and 1.1 g/L, whereas the fed-batch shake flask process improved titers to 2.5–3.0 g/L. The lead 4A1 ACE cell line achieved titers of 4.0 g/L with an average specific productivity of 40 pg/(cell day) when cultured in a non optimized 2-L fed-batch bioreactor using a completely chemically defined process. Generational stability characterization of the lead 4A1-expressing cell line demonstrated that the cell line was stable for up to 75 days in culture. Product quality attributes of the 4A1 MAb produced by the ACE system during the stability evaluation period were unchanged and also comparable to existing expression technologies such as the CHO-dhfr system. The results of this evaluation demonstrate that a clonal, stable MAb-expressing CHO cell line can be produced using ACE technology that performs competitively using a chemically defined fed-batch bioreactor process with comparable product quality attributes to cell lines generated by existing technologies.

  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. Neural Network-Based State Estimation for a Closed-Loop Control Strategy Applied to a Fed-Batch Bioreactor

    Directory of Open Access Journals (Sweden)

    Santiago Rómoli

    2017-01-01

    Full Text Available The lack of online information on some bioprocess variables and the presence of model and parametric uncertainties pose significant challenges to the design of efficient closed-loop control strategies. To address this issue, this work proposes an online state estimator based on a Radial Basis Function (RBF neural network that operates in closed loop together with a control law derived on a linear algebra-based design strategy. The proposed methodology is applied to a class of nonlinear systems with three types of uncertainties: (i time-varying parameters, (ii uncertain nonlinearities, and (iii unmodeled dynamics. To reduce the effect of uncertainties on the bioreactor, some integrators of the tracking error are introduced, which in turn allow the derivation of the proper control actions. This new control scheme guarantees that all signals are uniformly and ultimately bounded, and the tracking error converges to small values. The effectiveness of the proposed approach is illustrated on the basis of simulated experiments on a fed-batch bioreactor, and its performance is compared with two controllers available in the literature.

  7. Stochastic models to study the impact of mixing on a fed-batch culture of Saccharomyces cerevisiae.

    Science.gov (United States)

    Delvigne, F; Lejeune, A; Destain, J; Thonart, P

    2006-01-01

    The mechanisms of interaction between microorganisms and their environment in a stirred bioreactor can be modeled by a stochastic approach. The procedure comprises two submodels: a classical stochastic model for the microbial cell circulation and a Markov chain model for the concentration gradient calculus. The advantage lies in the fact that the core of each submodel, i.e., the transition matrix (which contains the probabilities to shift from a perfectly mixed compartment to another in the bioreactor representation), is identical for the two cases. That means that both the particle circulation and fluid mixing process can be analyzed by use of the same modeling basis. This assumption has been validated by performing inert tracer (NaCl) and stained yeast cells dispersion experiments that have shown good agreement with simulation results. The stochastic model has been used to define a characteristic concentration profile experienced by the microorganisms during a fermentation test performed in a scale-down reactor. The concentration profiles obtained in this way can explain the scale-down effect in the case of a Saccharomyces cerevisiae fed-batch process. The simulation results are analyzed in order to give some explanations about the effect of the substrate fluctuation dynamics on S. cerevisiae.

  8. 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.

  9. 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.

  10. Biosynthesis of Citric Acid from Glycerol by Acetate Mutants of Yarrowia lipolytica in Fed-Batch Fermentation

    Directory of Open Access Journals (Sweden)

    Anita Rywińska

    2009-01-01

    Full Text Available Pure and crude glycerol from biodiesel production have been used as substrates for citric acid production by acetate-negative mutants of Yarrowia lipolytica in fed-batch fermentation. Both the final concentration and the yield of the product were the highest when Y. lipolytica Wratislavia AWG7 strain was used in the culture with pure or crude glycerol. With a medium containing 200 g/L of glycerol, production reached a maximum of citric acid of 139 g/L after 120 h. This high yield of the product (up to 0.69 g of citric acid per gram of glycerol consumed was achieved with both pure and crude glycerol. Lower yield of citric acid in the culture with Y. lipolytica Wratislavia K1 strain (about 0.45 g/g resulted from increased erythritol concentrations (up to 40 g/L, accumulated simultaneously with the citric acid. The concentration of isocitric acid, a by-product in this fermentation, was very low, in the range from 2.6 to 4.6 g/L.

  11. 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.

  12. Combined data preprocessing and multivariate statistical analysis characterizes fed-batch culture of mouse hybridoma cells for rational medium design.

    Science.gov (United States)

    Selvarasu, Suresh; Kim, Do Yun; Karimi, Iftekhar A; Lee, Dong-Yup

    2010-10-01

    We present an integrated framework for characterizing fed-batch cultures of mouse hybridoma cells producing monoclonal antibody (mAb). This framework systematically combines data preprocessing, elemental balancing and statistical analysis technique. Initially, specific rates of cell growth, glucose/amino acid consumptions and mAb/metabolite productions were calculated via curve fitting using logistic equations, with subsequent elemental balancing of the preprocessed data indicating the presence of experimental measurement errors. Multivariate statistical analysis was then employed to understand physiological characteristics of the cellular system. The results from principal component analysis (PCA) revealed three major clusters of amino acids with similar trends in their consumption profiles: (i) arginine, threonine and serine, (ii) glycine, tyrosine, phenylalanine, methionine, histidine and asparagine, and (iii) lysine, valine and isoleucine. Further analysis using partial least square (PLS) regression identified key amino acids which were positively or negatively correlated with the cell growth, mAb production and the generation of lactate and ammonia. Based on these results, the optimal concentrations of key amino acids in the feed medium can be inferred, potentially leading to an increase in cell viability and productivity, as well as a decrease in toxic waste production. The study demonstrated how the current methodological framework using multivariate statistical analysis techniques can serve as a potential tool for deriving rational medium design strategies. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Enhanced fed-batch production of pyrroloquinoline quinine in Methylobacillus sp. CCTCC M2016079 with a two-stage pH control strategy.

    Science.gov (United States)

    Si, Zhenjun; Machaku, David; Wei, Peilian; Huang, Lei; Cai, Jin; Xu, Zhinan

    2017-06-01

    The effects of pH control strategy and fermentative operation modes on the biosynthesis of pyrroloquinoline quinine (PQQ) were investigated systematically with Methylobacillus sp. CCTCC M2016079 in the present work. Firstly, the shake-flask cultivations and benchtop fermentations at various pH values ranging from 5.3 to 7.8 were studied. Following a kinetic analysis of specific cell growth rate (μ x ) and specific PQQ formation rate (μ p ), the discrepancy in optimal pH values between cell growth and PQQ biosynthesis was observed, which stimulated us to develop a novel two-stage pH control strategy. During this pH-shifted process, the pH in the broth was controlled at 6.8 to promote the cell growth for the first 48 h and then shifted to 5.8 to enhance the PQQ synthesis until the end of fermentation. By applying this pH-shifted control strategy, the maximum PQQ production was improved to 158.61 mg/L in the benchtop fermenter, about 44.9% higher than that under the most suitable constant pH fermentation. Further fed-batch study showed that PQQ production could be improved from 183.38 to 272.21 mg/L by feeding of methanol at the rate of 11.5 mL/h in this two-stage pH process. Meanwhile, the productivity was also increased from 2.02 to 2.84 mg/L/h. In order to support cell growth during the shifted pH stage, the combined feeding of methanol and yeast extract was carried out, which brought about the highest concentration (353.28 mg/L) and productivity (3.27 mg/L/h) of PQQ. This work has revealed the potential of our developed simple and economical strategy for the large-scale production of PQQ.

  14. Systematic optimization of fed-batch simultaneous saccharification and fermentation at high-solid loading based on enzymatic hydrolysis and dynamic metabolic modeling of Saccharomyces cerevisiae.

    Science.gov (United States)

    Unrean, Pornkamol; Khajeeram, Sutamat; Laoteng, Kobkul

    2016-03-01

    An integrative simultaneous saccharification and fermentation (SSF) modeling is a useful guiding tool for rapid process optimization to meet the techno-economic requirement of industrial-scale lignocellulosic ethanol production. In this work, we have developed the SSF model composing of a metabolic network of a Saccharomyces cerevisiae cell associated with fermentation kinetics and enzyme hydrolysis model to quantitatively capture dynamic responses of yeast cell growth and fermentation during SSF. By using model-based design of feeding profiles for substrate and yeast cell in the fed-batch SSF process, an efficient ethanol production with high titer of up to 65 g/L and high yield of 85 % of theoretical yield was accomplished. The ethanol titer and productivity was increased by 47 and 41 %, correspondingly, in optimized fed-batch SSF as compared to batch process. The developed integrative SSF model is, therefore, considered as a promising approach for systematic design of economical and sustainable SSF bioprocessing of lignocellulose.

  15. 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.

  16. Quantitative evaluation of yeast's requirement for glycerol formation in very high ethanol performance fed-batch process

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    Nevoigt Elke

    2010-05-01

    Full Text Available Abstract Background Glycerol is the major by-product accounting for up to 5% of the carbon in Saccharomyces cerevisiae ethanolic fermentation. Decreasing glycerol formation may redirect part of the carbon toward ethanol production. However, abolishment of glycerol formation strongly affects yeast's robustness towards different types of stress occurring in an industrial process. In order to assess whether glycerol production can be reduced to a certain extent without jeopardising growth and stress tolerance, the yeast's capacity to synthesize glycerol was adjusted by fine-tuning the activity of the rate-controlling enzyme glycerol 3-phosphate dehydrogenase (GPDH. Two engineered strains whose specific GPDH activity was significantly reduced by two different degrees were comprehensively characterized in a previously developed Very High Ethanol Performance (VHEP fed-batch process. Results The prototrophic strain CEN.PK113-7D was chosen for decreasing glycerol formation capacity. The fine-tuned reduction of specific GPDH activity was achieved by replacing the native GPD1 promoter in the yeast genome by previously generated well-characterized TEF promoter mutant versions in a gpd2Δ background. Two TEF promoter mutant versions were selected for this study, resulting in a residual GPDH activity of 55 and 6%, respectively. The corresponding strains were referred to here as TEFmut7 and TEFmut2. The genetic modifications were accompanied to a strong reduction in glycerol yield on glucose; the level of reduction compared to the wild-type was 61% in TEFmut7 and 88% in TEFmut2. The overall ethanol production yield on glucose was improved from 0.43 g g-1 in the wild type to 0.44 g g-1 measured in TEFmut7 and 0.45 g g-1 in TEFmut2. Although maximal growth rate in the engineered strains was reduced by 20 and 30%, for TEFmut7 and TEFmut2 respectively, strains' ethanol stress robustness was hardly affected; i.e. values for final ethanol concentration (117 ± 4 g

  17. Transformation of ferulic acid to vanillin using a fed-batch solid-liquid two-phase partitioning bioreactor.

    Science.gov (United States)

    Ma, Xiao-kui; Daugulis, Andrew J

    2014-01-01

    Amycolatopsis sp. ATCC 39116 (formerly Streptomyces setonii) has shown promising results in converting ferulic acid (trans-4-hydroxy-3-methoxycinnamic acid; substrate), which can be derived from natural plant wastes, to vanillin (4-hydroxy-3-methoxybenzaldehyde). After exploring the influence of adding vanillin at different times during the growth cycle on cell growth and transformation performance of this strain and demonstrating the inhibitory effect of vanillin, a solid-liquid two-phase partitioning bioreactor (TPPB) system was used as an in situ product removal technique to enhance transformation productivity by this strain. The thermoplastic polymer Hytrel(®) G4078W was found to have superior partitioning capacity for vanillin with a partition coefficient of 12 and a low affinity for the substrate. A 3-L working volume solid-liquid fed-batch TPPB mode, using 300 g Hytrel G4078W as the sequestering phase, produced a final vanillin concentration of 19.5 g/L. The overall productivity of this reactor system was 450 mg/L. h, among the highest reported in literature. Vanillin was easily and quantitatively recovered from the polymers mostly by single stage extraction into methanol or other organic solvents used in food industry, simultaneously regenerating polymer beads for reuse. A polymer-liquid two phase bioreactor was again confirmed to easily outperform single phase systems that feature inhibitory or easily further degraded substrates/products. This enhancement strategy might reasonably be expected in the production of other flavor and fragrance compounds obtained by biotransformations. © 2013 American Institute of Chemical Engineers.

  18. Bioelectricity generation from coconut husk retting wastewater in fed batch operating microbial fuel cell by phenol degrading microorganism

    International Nuclear Information System (INIS)

    Jayashree, C.; Arulazhagan, P.; Adish Kumar, S.; Kaliappan, S.; Yeom, Ick Tae; Rajesh Banu, J.

    2014-01-01

    Dual chamber microbial fuel cell (MFC) operated at fed batch mode for the treatment of retting wastewater has potently achieved both current generation and phenol removal. Hydraulic retention time (HRT) of the reactor was varied from 40 days to 10 days. COD (chemical oxygen demand) removal was 91% at 40 days HRT, with an initial COD concentration of 530 ± 50 g m −3 . Retting wastewater with an initial phenol concentration of 320 ± 60 g m −3 procured a highest phenol removal of 93% at 40 days HRT of the microbial fuel cell. Maximum power density of 362 mW m −2 was achieved using retting wastewater at HRT of 20 days with an internal resistance of 150 Ω in a dual chambered MFC. The bacterial strains in anode region, reported to be responsible for potential phenol removal, were identified as Ochrobactrum sp. RA1 (KJ408266), Ochrobactrum sp. RA2 (KJ408267) and Pesudomonas aeruginosa RA3 (KJ408268) using phylogenetic analysis. The study reveals that, dual chambered MFC effectively removed the phenol from retting wastewater along with power generation. - Highlights: • Maximum power density of 362 mW m −2 (150 Ω) was achieved at HRT of 20 days. • 91% COD removal and 93% phenol removal was observed at HRT of 40 days. • 25% coulombic efficiency was achieved in treatment of retting wastewater with MFC. • Phylogenetic analysis detect phenol degrading Ochrobactrum sp.RA1 in anode biofilm. • In addition, Ochrobactrum sp.RA2 and Pseudomonas aeruginosa RA3 were also isolated

  19. Systematic development of a two-stage fed-batch process for lipid accumulation in Rhodotorula glutinis.

    Science.gov (United States)

    Lorenz, Eric; Runge, Dennis; Marbà-Ardébol, Anna-Maria; Schmacht, Maximilian; Stahl, Ulf; Senz, Martin

    2017-03-20

    The application of oleaginous yeast cells as feed supplement, for instance in aqua culture, can be a meaningful alternative for fish meal and oil additives. Therefore, a two-stage fed-batch process split into growth and lipogenesis phase was systematically developed to enrich the oleaginous yeast Rhodotorula glutinis Rh-00301 with high amounts of lipids at industrial relevant biomasses. Thereby, the different carbon sources glucose, sucrose and glycerol were investigated concerning their abilities to serve as a suited raw material for growth and/or lipid accumulation. With the background of economic efficiency C/N ratios of 40, 50 and 70 were investigated as well. It became apparent that glycerol is an improper carbon source most likely because of the passive diffusion of this compound caused by absence of active transporters. The opposite was observed for sucrose, which is the main carbon source in molasses. Finally, an industrially applicable process was successfully established that ensures biomasses of 106±2gL -1 combined with an attractive lipid content of 63±6% and a high lipid-substrate yield (Y L/S ) of 0.18±0.02gg -1 in a short period of time (84h). Furthermore, during these studies a non-negligible formation of the by-product glycerol was detected. This characteristic of R. glutinis is discussed related to other oleaginous yeasts, where glycerol formation is absent. Nevertheless, due to modifications in the feeding procedure, the formation of glycerol could have been reduced but not avoided. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. User-friendly optimization approach of fed-batch fermentation conditions for the production of iturin A using artificial neural networks and support vector machine

    Directory of Open Access Journals (Sweden)

    Fudi Chen

    2015-07-01

    Conclusion: According to the modeling results, the GRNN is considered as the most suitable ANN model for the design of the fed-batch fermentation conditions for the production of iturin A because of its high robustness and precision, and the SVM is also considered as a very suitable alternative model. Under the tolerance of 30%, the prediction accuracies of the GRNN and SVM are both 100% respectively in repeated experiments.

  1. Acquisition of data from on-line laser turbidimeter and calculation of some kinetic variables in computer-coupled automated fed-batch culture

    International Nuclear Information System (INIS)

    Kadotani, Y.; Miyamoto, K.; Mishima, N.; Kominami, M.; Yamane, T.

    1995-01-01

    Output signals of a commercially available on-line laser turbidimeter exhibit fluctuations due to air and/or CO 2 bubbles. A simple data processing algorithm and a personal computer software have been developed to smooth the noisy turbidity data acquired, and to utilize them for the on-line calculations of some kinetic variables involved in batch and fed-batch cultures of uniformly dispersed microorganisms. With this software, about 10 3 instantaneous turbidity data acquired over 55 s are averaged and convert it to dry cell concentration, X, every minute. Also, volume of the culture broth, V, is estimated from the averaged output data of weight loss of feed solution reservoir, W, using an electronic balance on which the reservoir is placed. Then, the computer software is used to perform linear regression analyses over the past 30 min of the total biomass, VX, the natural logarithm of the total biomass, ln(VX), and the weight loss, W, in order to calculate volumetric growth rate, d(VX)/dt, specific growth rate, μ [ = dln(VX)/dt] and the rate of W, dW/dt, every minute in a fed-batch culture. The software used to perform the first-order regression analyses of VX, ln(VX) and W was applied to batch or fed-batch cultures of Escherichia coli on minimum synthetic or natural complex media. Sample determination coefficients of the three different variables (VX, ln(VX) and W) were close to unity, indicating that the calculations are accurate. Furthermore, growth yield, Y x/s , and specific substrate consumption rate, q sc , were approximately estimated from the data, dW/dt and in a ‘balanced’ fed-batch culture of E. coli on the minimum synthetic medium where the computer-aided substrate-feeding system automatically matches well with the cell growth. (author)

  2. Dextran Utilization During Its Synthesis by Weissella cibaria RBA12 Can Be Overcome by Fed-Batch Fermentation in a Bioreactor.

    Science.gov (United States)

    Baruah, Rwivoo; Deka, Barsha; Kashyap, Niharika; Goyal, Arun

    2018-01-01

    Weissella cibaria RBA12 produced a maximum of 9 mg/ml dextran (with 90% efficiency) using shake flask culture under the optimized concentration of medium components viz. 2% (w/v) of each sucrose, yeast extract, and K 2 HPO 4 after incubation at optimized conditions of 20 °C and 180 rpm for 24 h. The optimized medium and conditions were used for scale-up of dextran production from Weissella cibaria RBA12 in 2.5-l working volume under batch fermentation in a bioreactor that yielded a maximum of 9.3 mg/ml dextran (with 93% efficiency) at 14 h. After 14 h, dextran produced was utilized by the bacterium till 18 h in its stationary phase under sucrose depleted conditions. Dextran utilization was further studied by fed-batch fermentation using sucrose feed. Dextran on production under fed-batch fermentation in bioreactor gave 35.8 mg/ml after 32 h. In fed-batch mode, there was no decrease in dextran concentration as observed in the batch mode. This showed that the utilization of dextran by Weissella cibaria RBA12 is initiated when there is sucrose depletion and therefore the presence of sucrose can possibly overcome the dextran hydrolysis. This is the first report of utilization of dextran, post-sucrose depletion by Weissella sp. studied in bioreactor.

  3. An optimized fed-batch culture strategy integrated with a one-step fermentation improves L-lactic acid production by Rhizopus oryzae.

    Science.gov (United States)

    Fu, Yongqian; Sun, Xiaolong; Zhu, Huayue; Jiang, Ru; Luo, Xi; Yin, Longfei

    2018-05-21

    In previous work, we proposed a novel modified one-step fermentation fed-batch strategy to efficiently generate L-lactic acid (L-LA) using Rhizopus oryzae. In this study, to further enhance efficiency of L-LA production through one-step fermentation in fed-batch cultures, we systematically investigated the initial peptone- and glucose-feeding approaches, including different initial peptone and glucose concentrations and maintained residual glucose levels. Based on the results of this study, culturing R. oryzae with initial peptone and glucose concentrations of 3.0 and 50.0 g/l, respectively, using a fed-batch strategy is an effective approach of producing L-LA through one-step fermentation. Changing the residual glucose had no obvious effect on the generation of L-LA. We determined the maximum LA production and productivity to be 162 g/l and 6.23 g/(l·h), respectively, during the acid production stage. Compared to our previous work, there was almost no change in L-LA production or yield; however, the productivity of L-LA increased by 14.3%.

  4. Different cultivation methods to acclimatise ammonia-tolerant methanogenic consortia

    DEFF Research Database (Denmark)

    Tian, Hailin; Fotidis, Ioannis; Mancini, Enrico

    2017-01-01

    reactors (i.e. batch, fed-batch and continuous stirred-tank reactors (CSTR)) operated at mesophilic (37°C) and thermophilic (55°C) conditions were assessed, based on methane production efficiency, incubation time, TAN/FAN (total ammonium nitrogen/free ammonia nitrogen) levels and maximum methanogenic...... activity. Overall, fed-batch cultivation was clearly the most efficient method compared to batch and CSTR. Specifically, by saving incubation time up to 150%, fed-batch reactors were acclimatised to nearly 2-fold higher FAN levels with a 37%-153% methanogenic activity improvement, compared to batch method....... Meanwhile, CSTR reactors were inhibited at lower ammonia levels. Finally, specific methanogenic activity test showed that hydrogenotrophic methanogens were more active than aceticlastic methanogens in all FAN levels above 540 mg NH3-N L-1....

  5. Improved productivity of poly (3-hydroxybutyrate) (PHB) in thermophilic Chelatococcus daeguensis TAD1 using glycerol as the growth substrate in a fed-batch culture.

    Science.gov (United States)

    Cui, Bin; Huang, Shaobin; Xu, Fuqian; Zhang, Ruijian; Zhang, Yongqing

    2015-07-01

    A particularly successful polyhydroxyalkanoate (PHA) in industrial applications is poly (3-hydroxybutyrate) (PHB). However, one of the major obstacles for wider application of PHB is the cost of its production and purification. Therefore, it is desirable to discover a method for producing PHB in large quantities at a competitive price. Glycerol is a cheap and widely used carbon source that can be applied in PHB production process. There are numerous advantages to operating fermentation at elevated temperatures; only several thermophilic bacteria are able to accumulate PHB when glycerol is the growth substrate. Here, we report on the possibility of increasing PHB production at low cost using thermophilic Chelatococcus daeguensis TAD1 when glycerol is the growth substrate in a fed-batch culture. We found that (1) excess glycerol inhibited PHB accumulation and (2) organic nitrogen sources, such as tryptone and yeast extract, promoted the growth of C. daeguensis TAD1. In the batch fermentation experiments, we found that using glycerol at low concentrations as the sole carbon source, along with the addition of mixed nitrate (NH4Cl, tryptone, and yeast extract), stimulated PHB accumulation in C. daeguensis TAD1. The results showed that the PHB productivity decreased in the following order: two-stage fed-batch fermentation > fed-batch fermentation > batch fermentation. In optimized culture conditions, a PHB amount of 17.4 g l(-1) was obtained using a two-stage feeding regimen, leading to a productivity rate of 0.434 g l(-1) h(-1), which is the highest productivity rate reported for PHB to date. This high PHB biosynthetic productivity could decrease the total production cost, allowing for further development of industrial applications of PHB.

  6. Characteristics of Corn Stover Pretreated with Liquid Hot Water and Fed-Batch Semi-Simultaneous Saccharification and Fermentation for Bioethanol Production

    Science.gov (United States)

    Li, Xuezhi; Lu, Jie; Zhao, Jian; Qu, Yinbo

    2014-01-01

    Corn stover is a promising feedstock for bioethanol production because of its abundant availability in China. To obtain higher ethanol concentration and higher ethanol yield, liquid hot water (LHW) pretreatment and fed-batch semi-simultaneous saccharification and fermentation (S-SSF) were used to enhance the enzymatic digestibility of corn stover and improve bioconversion of cellulose to ethanol. The results show that solid residues from LHW pretreatment of corn stover can be effectively converted into ethanol at severity factors ranging from 3.95 to 4.54, and the highest amount of xylan removed was approximately 89%. The ethanol concentrations of 38.4 g/L and 39.4 g/L as well as ethanol yields of 78.6% and 79.7% at severity factors of 3.95 and 4.54, respectively, were obtained by fed-batch S-SSF in an optimum conditions (initial substrate consistency of 10%, and 6.1% solid residues added into system at the prehydrolysis time of 6 h). The changes in surface morphological structure, specific surface area, pore volume and diameter of corn stover subjected to LHW process were also analyzed for interpreting the possible improvement mechanism. PMID:24763192

  7. 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.

  8. Fed batch enzymatic saccharification of food waste improves the sugar concentration in the hydrolysates and eventually the ethanol fermentation by Saccharomyces cerevisiae H058

    Directory of Open Access Journals (Sweden)

    Shoubao Yan

    2012-04-01

    Full Text Available The enzymatic hydrolysis of food waste by commercially available enzymes and the subsequent ethanol fermentation of the hydrolysates by Saccharomyces cerecisiae H058 were studied in this work. The optimum batch enzymatic conditions were found to be saccharification pH of 4.5, temperature of 55!, glucoamylase concentration of 120 u/g, α-amylase concentration of 10 u/g, solid-liquid ratio of 1: 0.75 (w/w. Fed batch hydrolysis process was started with a solid-liquid ratio of 1: 1 (w/w, with solid food waste added at time lapse of 2 h to get a final solid-liquid ratio of 1: 0.5 (w/w. After 4 h of reaction, the reducing sugar concentration reached 194.43 g/L with a enzymatic digestibility of 93.12%. Further fermentation of the batch and fed batch enzymatic hydrolysates, which contained reducing sugar concentration of 131.41 and 194.43 g/L respectively, was performed using Saccharomyces cerevisiae H058, 62.93 and 90.72 g/L ethanol was obtained within 48 h.

  9. Semi-industrial scale (30 m3) fed-batch fermentation for the production of D-lactate by Escherichia coli strain HBUT-D15.

    Science.gov (United States)

    Fu, Xiangmin; Wang, Yongze; Wang, Jinhua; Garza, Erin; Manow, Ryan; Zhou, Shengde

    2017-02-01

    D(-)-lactic acid is needed for manufacturing of stereo-complex poly-lactic acid polymer. Large scale D-lactic acid fermentation, however, has yet to be demonstrated. A genetically engineered Escherichia coli strain, HBUT-D, was adaptively evolved in a 15% calcium lactate medium for improved lactate tolerance. The resulting strain, HBUT-D15, was tested at a lab scale (7 L) by fed-batch fermentation with up to 200 g L -1 of glucose, producing 184-191 g L -1 of D-lactic acid, with a volumetric productivity of 4.38 g L -1  h -1 , a yield of 92%, and an optical purity of 99.9%. The HBUT-D15 was then evaluated at a semi-industrial scale (30 m 3 ) via fed-batch fermentation with up to 160 g L -1 of glucose, producing 146-150 g L -1 of D-lactic acid, with a volumetric productivity of 3.95-4.29 g L -1  h -1 , a yield of 91-94%, and an optical purity of 99.8%. These results are comparable to that of current industrial scale L(+)-lactic acid fermentation.

  10. An integral term adaptive neural control of fed-batch fermentation biotechnological process; Control neuronal adaptable con termino integral para un proceso biotecnologico de fermentacion por lote alimentado

    Energy Technology Data Exchange (ETDEWEB)

    Baruch, Ieroham; Hernandez, Luis Alberto; Barrera Cortes, Josefina [Centro de Investigacion y de Estudios Avanzados, Instituto Politecnico Nacional, Mexico D.F. (Mexico)

    2005-07-15

    A nonlinear mathematical model of aerobic biotechnological process of a fed-batch fermentation system is derived using ordinary differential equations. A neurocontrol is applied using Recurrent Trainable Neural Network (RTNN) plus integral term; the first network performs an approximation of the plant's output; the second network generates the control signal so that the biomass concentration could be regulated by the nutrient influent flow rate into the bioreactor. [Spanish] Un modelo matematico no lineal de un proceso biotecnologico aerobio de un sistema de fermentacion por lote alimentado es presentado mediante ecuaciones diferenciales ordinarias. Es propuesto un control utilizando dos redes neuronales recurrentes entrenables (RNRE) con la adicion de un termino integral; la primera red representa un aproximador de la salida de la planta y la segunda genera la senal de control tal que la concentracion de la biomasa pueda ser regulada mediante la alimentacion de un flujo con nutrientes al biorreactor.

  11. 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

    to the interplay between the dilution effect associated with change in specific productivity of mAbs and the changed nucleotide sugar metabolism. Herein, we also show and discuss that increased cell culture duration negatively affect the maturation of glycans. In addition, comparative proteomics analysis of cells......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 quality. Titer and N-glycosylation of mAbs, as well as proteomic signature and metabolic status of the production cells in the culture were assessed. We found that the impact of glucose starvation on the titer and N-glycosylation of mAbs was dependent on the degree of starvation during early stationary...

  12. An investigation into the preservation of microbial cell banks for α-amylase production during 5 l fed-batch Bacillus licheniformis fermentations.

    Science.gov (United States)

    Hancocks, Nichola H; Thomas, Colin R; Stocks, Stuart M; Hewitt, Christopher J

    2010-10-01

    Fluorescent staining techniques were used for a systematic examination of methods used to cryopreserve microbial cell banks. The aim of cryopreservation here is to ensure subsequent reproducible fermentation performance rather than just post thaw viability. Bacillus licheniformis cell physiology post-thaw is dependent on the cryopreservant (either Tween 80, glycerol or dimethyl sulphoxide) and whilst this had a profound effect on the length of the lag phase, during subsequent 5 l fed-batch fermentations, it had little effect on maximum specific growth rate, final biomass concentration or α-amylase activity. Tween 80 not only protected the cells during freezing but also helped them recover post-thaw resulting in shorter process times.

  13. Adaptation of the xylose fermenting yeast Saccharomyces cerevisiae F12 for improving ethanol production in different fed-batch SSF processes.

    Science.gov (United States)

    Tomás-Pejó, E; Ballesteros, M; Oliva, J M; Olsson, L

    2010-11-01

    An efficient fermenting microorganism for bioethanol production from lignocellulose is highly tolerant to the inhibitors released during pretreatment and is able to ferment efficiently both glucose and xylose. In this study, directed evolution was employed to improve the xylose fermenting Saccharomyces cerevisiae F12 strain for bioethanol production at high substrate loading. Adapted and parental strains were compared with respect to xylose consumption and ethanol production. Adaptation led to an evolved strain more tolerant to the toxic compounds present in the medium. When using concentrated prehydrolysate from steam-pretreated wheat straw with high inhibitor concentration, an improvement of 65 and 20% in xylose consumption and final ethanol concentration, respectively, were achieved using the adapted strain. To address the need of high substrate loadings, fed-batch SSF experiments were performed and an ethanol concentration as high as 27.4 g/l (61% of the theoretical) was obtained with 11.25% (w/w) of water insoluble solids (WIS).

  14. The small laccase from Streptomyces coelicolor

    Czech Academy of Sciences Publication Activity Database

    Dohnálek, Jan; Skálová, Tereza; Ostergaard, L. H.; Ostergaard, P. R.; Hašek, Jindřich

    2009-01-01

    Roč. 16, 1a (2009), b4-b5 ISSN 1211-5894. [Discussions in Structural Molecular Biology /7./. 12.03.2009-14.03.2009, Nové Hrady] R&D Projects: GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : laccase * Streptomyces coelicolor * enzymer Subject RIV: CD - Macromolecular Chemistry

  15. Fed-batch cultivation of baker's yeast followed by nitrogen or carbon starvation: effects on fermentative capacity and content of trehalose and glycogen

    DEFF Research Database (Denmark)

    Jørgensen, Henning; Olsson, Lisbeth; Rønnow, B.

    2002-01-01

    , trehalose and glycogen. Nitrogen starvation triggered the accumulation of trehalose and glycogen. After 8 h of starvation, the content of trehalose and glycogen was increased 4-fold and 2-fold, respectively. Carbon starvation resulted in a partial conversion of glycogen into trehalose. The trehalose content...... increased from 45 to 64 mg (g dry-weight)(-1), whereas the glycogen content in the same period was reduced from 55 to 5 mg (g dry-weight)(-1). Glycogen was consumed faster than trehalose during storage of the starved yeast for 1 month. Nitrogen starvation resulted in a decrease in the protein content...

  16. Production of farnesene and santalene by Saccharomyces cerevisiae using fed-batch cultivations with RQ-controlled feed

    DEFF Research Database (Denmark)

    Tippmann, Stefan; Scalcinati, Gionata; Siewers, Verena

    2016-01-01

    Terpenes have various applications as fragrances, cosmetics and fuels. One of the most prominent examples is the sesquiterpene farnesene, which can be used as diesel substitute in its hydrogenated form farnesane. Recent metabolic engineering efforts have enabled efficient production of several te...

  17. Functional State Modelling of Saccharomyces cerevisiae Cultivations

    Directory of Open Access Journals (Sweden)

    Iasen Hristozov

    2004-10-01

    Full Text Available The implementation of functional state approach for modelling of yeast cultivation is considered in this paper. This concept helps in monitoring and control of complex processes such as bioprocesses. Using of functional state modelling approach for fermentation processes aims to overcome the main disadvantage of using global process model, namely complex model structure and big number of model parameters. The main advantage of functional state modelling is that the parameters of each local model can be separately estimated from other local models parameters. The results achieved from batch, as well as from fed-batch, cultivations are presented.

  18. Production of oleic acid ethyl ester catalyzed by crude rice bran (Oryza sativa lipase in a modified fed-batch system: problem and its solution

    Directory of Open Access Journals (Sweden)

    Indro Prastowo

    2015-01-01

    Full Text Available A fed-batch system was modified for the enzymatic production of Oleic Acid Ethyl Ester (OAEE using rice bran (Oryza sativa lipase by retaining the substrate molar ratio (ethanol/oleic acid at 2.05: 1 during the reaction. It resulted in an increase in the ester conversion up to 76.8% in the first 6 h of the reaction, and then followed by a decrease from 76.8% to 22.9% in 6 h later. Meanwhile, the production of water in the reaction system also showed a similar trend to the trend of ester production. The water was hypothesized to lead lipase to reverse the reaction which resulted in a decrease in both (water and esters in the last 6 h of the reaction. In order to overcome the problem, zeolite powders (25 and 50 mg/ml were added into the reaction system at 5 h of the reaction. As the result, final ester conversions increased drastically up to 90 - 95.7% (1.17 – 1.24 times. The addition also proved a hypothesis that the water was involved in reducing the ester conversion in the last 6 h of the reaction. Thus, the combination was effective to produce the high final ester conversion.

  19. Pilot scale repeated fed-batch fermentation processes of the wine yeast Dekkera bruxellensis for mass production of resveratrol from Polygonum cuspidatum.

    Science.gov (United States)

    Kuo, Hsiao-Ping; Wang, Reuben; Lin, Yi-Sheng; Lai, Jinn-Tsyy; Lo, Yi-Chen; Huang, Shyue-Tsong

    2017-11-01

    Resveratrol has long been used as an ingredient in functional foods. Currently, Polygonum cuspidatum extract is the greatest natural source for resveratrol because of high concentrations of glycosidic-linked resveratrol. Thus, developing a cost-effective procedure to hydrolyze glucoside could substantially enhance resveratrol production from P. cuspidatum. This study selected Dekkera bruxellensis from several microorganisms based on its bioconversion and enzyme-specific activities. We demonstrated that the cells could be reused at least nine times while maintaining an average of 180.67U/L β-glucosidase activity. The average resveratrol bioconversion efficiency within five rounds of repeated usage was 108.77±0.88%. This process worked effectively when the volume was increased to 1200L, a volume at which approximately 35mgL -1 h -1 resveratrol per round was produced. This repeated fed-batch bioconversion process for resveratrol production is comparable to enzyme or cell immobilization strategies in terms of reusing cycles, but without incurring additional costs for immobilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Dietary supplementation with bovine lactoferrampin-lactoferricin produced by Pichia pastoris fed-batch fermentation affects intestinal microflora in weaned piglets.

    Science.gov (United States)

    Tang, Xiang-Shan; Shao, Hua; Li, Tie-Jun; Tang, Zhi-Ru; Huang, Rui-Ling; Wang, Sheng-Ping; Kong, Xiang-Feng; Wu, Xin; Yin, Yu-Long

    2012-10-01

    This work is aimed at investigating the effects of recombinant bovine lactoferrampin-lactoferricin (LFA-LFC) instead of chlortetracycline on intestinal microflora in weaned piglets. The high cost of peptide production from either native digestion or chemical synthesis limits the clinical application of antimicrobial peptides. The expression of recombinant peptides in yeast may be an effective alternative. In the current study, recombinant LFA-LFC was produced via fed-batch fermentation in recombinant strain Pichia pastoris (KM71) XS10. Uniform design U6(6(4)) was used to optimize the fermentation conditions. The target peptide purified via cation-exchange and size-exclusion chromatography was added into the dietary of weaned piglets. After 21 days, the Lactobacilli, Bifidobacteria, and Enterobacteria in the chyme of the gut were quantified using real-time polymerase chain reaction. The results showed that approximately 82 mg of LFA-LFC was secreted into 1 L of medium under optimized conditions. Moreover, purified peptide showed strong antimicrobial activities against all the tested microorganisms. Compared with the control group, the LFA-LFC group increased the amount of Lactobacilli and Bifidobacteria (P<0.05) in the chyme of the stomach, duodenum, jejunum, ileum, colon, and caecum. These results show that dietary supplementation with LFA-LFC can affect intestinal microflora in weaned piglets.

  1. Fed-batch methanol feeding strategy for recombinant protein production by Pichia pastoris in the presence of co-substrate sorbitol.

    Science.gov (United States)

    Celik, Eda; Calik, Pinar; Oliver, Stephen G

    2009-09-01

    Batch-wise sorbitol addition as a co-substrate at the induction phase of methanol fed-batch fermentation by Pichia pastoris (Mut(+)) was proposed as a beneficial recombinant protein production strategy and the metabolic responses to methanol feeding rate in the presence of sorbitol was systematically investigated. Adding sorbitol batch-wise to the medium provided the following advantages over growth on methanol alone: (a) eliminating the long lag-phase for the cells and reaching 'high cell density production' at t = 24 h of the process (C(X) = 70 g CDW/l); (b) achieving 1.8-fold higher recombinant human erythropoietin (rHuEPO) (at t = 18 h); (c) reducing specific protease production 1.2-fold; (d) eliminating the lactic acid build-up period; (e) lowering the oxygen uptake rate two-fold; and (f) obtaining 1.4-fold higher overall yield coefficients. The maximum specific alcohol oxidase activity was not affected in the presence of sorbitol, and it was observed that sorbitol and methanol were utilized simultaneously. Thus, in the presence of sorbitol, 130 mg/l rHuEPO was produced at t = 24 h, compared to 80 mg/l rHuEPO (t = 24 h) on methanol alone. This work demonstrates not only the ease and efficiency of incorporating sorbitol to fermentations by Mut(+) strains of P. pastoris for the production of any bio-product, but also provides new insights into the metabolism of the methylotrophic yeast P. pastoris.

  2. Production of Medium-Chain-Length Poly(3-Hydroxyalkanoates from Saponified Palm Kernel Oil by Pseudomonas putida: Kinetics of Batch and Fed-Batch Fermentations

    Directory of Open Access Journals (Sweden)

    Annuar, M. S. M.

    2006-01-01

    Full Text Available The kinetics of medium-chain-length poly(3-hydroxyalkanoates, PHAMCL production by Pseudomonas putida PGA1 in batch and fed-batch fermentations were studied. With saponified palm kernel oil (SPKO supplying the free fatty acids mixture as the sole carbon and energy source, PHAMCL accumulation is encouraged under ammonium-limited condition, which is a nitrogen stress environment. The amount of PHAMCL accumulated and its specific production rate, qPHA were influenced by the residual ammonium concentration level in the culture medium. It was observed that in both fermentation modes, when the residual ammonium was exhausted (< 0.05 gL-1, the PHAMCL accumulation (11.9% and qPHA (0.0062 h-1 were significantly reduced. However, this effect can be reversed by feeding low amount of ammonium to the culture, resulting in significantly improved PHAMCL yield (71.4% and specific productivity (0.6 h-1. It is concluded that the feeding of low ammonium concentration to the culture medium during the PHAMCL accumulation has a positive effect on sustaining the PHAMCL biosynthetic capability of the organism. It was also found that increasing SPKO concentration in the medium significantly reduced (up to 50% the volumetric oxygen transfer coefficient (KLa of the fermentation system.

  3. 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.

  4. High-titer and productivity of l-(+)-lactic acid using exponential fed-batch fermentation with Bacillus coagulans arr4, a new thermotolerant bacterial strain.

    Science.gov (United States)

    Coelho, Luciana Fontes; Beitel, Susan Michelz; Sass, Daiane Cristina; Neto, Paulo Marcelo Avila; Contiero, Jonas

    2018-04-01

    Bacillus coagulans arr4 is a thermotolerant microorganism with great biotechnological potential for l-(+)-lactic acid production from granulated sugar and yeast extract. The highest l-(+)-lactic acid production was obtained with Ca(OH) 2 . The maximum production of l-(+)-lactic acid (206.81 g/L) was observed in exponential feeding using granulated sugar solution (900 g/L) and yeast extract (1%) at 50 °C, pH 6.5, and initial granulated sugar concentration of 100 g/L at 39 h. 5.3 g/L h productivity and 97% yield were observed, and no sugar remained. Comparing the simple batch with exponential fed-batch fermentation, the l(+) lactic acid production was improved in 133.22% and dry cell weight was improved in 83.29%, using granulated sugar and yeast extract. This study presents the highest productivity of lactic acid ever observed in the literature, on the fermentation of thermotolerant Bacillus sp. as well as an innovative and high-efficiency purification technology, using low-cost substances as Celite and charcoal. The recovery of lactic acid was 86%, with 100% protein removal, and the fermentation medium (brown color) became a colorless solution.

  5. Fed-batch hydrolysate addition and cell separation by settling in high cell density lignocellulosic ethanol fermentations on AFEX™ corn stover in the Rapid Bioconversion with Integrated recycling Technology process.

    Science.gov (United States)

    Sarks, Cory; Jin, Mingjie; Balan, Venkatesh; Dale, Bruce E

    2017-09-01

    The Rapid Bioconversion with Integrated recycling Technology (RaBIT) process uses enzyme and yeast recycling to improve cellulosic ethanol production economics. The previous versions of the RaBIT process exhibited decreased xylose consumption using cell recycle for a variety of different micro-organisms. Process changes were tested in an attempt to eliminate the xylose consumption decrease. Three different RaBIT process changes were evaluated in this work including (1) shortening the fermentation time, (2) fed-batch hydrolysate addition, and (3) selective cell recycling using a settling method. Shorting the RaBIT fermentation process to 11 h and introducing fed-batch hydrolysate addition eliminated any xylose consumption decrease over ten fermentation cycles; otherwise, decreased xylose consumption was apparent by the third cell recycle event. However, partial removal of yeast cells during recycle was not economical when compared to recycling all yeast cells.

  6. Performance of the auxotrophic Saccharomyces cerevisiae BY4741 as host for the production of IL-1β in aerated fed-batch reactor: role of ACA supplementation, strain viability, and maintenance energy

    Directory of Open Access Journals (Sweden)

    Zueco Jesus

    2009-12-01

    Full Text Available Abstract Background Saccharomyces cerevisiae BY4741 is an auxotrophic commonly used strain. In this work it has been used as host for the expression and secretion of human interleukin-1β (IL1β, using the cell wall protein Pir4 as fusion partner. To achieve high cell density and, consequently, high product yield, BY4741 [PIR4-IL1β] was cultured in an aerated fed-batch reactor, using a defined mineral medium supplemented with casamino acids as ACA (auxotrophy-complementing amino acid source. Also the S. cerevisiae mutant BY4741 Δyca1 [PIR4-IL1β], carrying the deletion of the YCA1 gene coding for a caspase-like protein involved in the apoptotic response, was cultured in aerated fed-batch reactor and compared to the parental strain, to test the effect of this mutation on strain robustness. Viability of the producer strains was examined during the runs and a mathematical model, which took into consideration the viable biomass present in the reactor and the glucose consumption for both growth and maintenance, was developed to describe and explain the time-course evolution of the process for both, the BY4741 parental and the BY4741 Δyca1 mutant strain. Results Our results show that the concentrations of ACA in the feeding solution, corresponding to those routinely used in the literature, are limiting for the growth of S. cerevisiae BY4741 [PIR4-IL1β] in fed-batch reactor. Even in the presence of a proper ACA supplementation, S. cerevisiae BY4741 [PIR4-IL1β] did not achieve a high cell density. The Δyca1 deletion did not have a beneficial effect on the overall performance of the strain, but it had a clear effect on its viability, which was not impaired during fed-batch operations, as shown by the kd value (0.0045 h-1, negligible if compared to that of the parental strain (0.028 h-1. However, independently of their robustness, both the parental and the Δyca1 mutant ceased to grow early during fed-batch runs, both strains using most of the

  7. Estudio comparativo de cuatro sistemas de propagación de levadura cervecera por lote alimentado Comparative study of four fed-batch propagation systems of beer yeast

    Directory of Open Access Journals (Sweden)

    Hoyos H.

    1998-06-01

    Full Text Available

    Se realizó la propagación por lotes de levadura cervecera y con base en estos resultados se ajustó un modelo matemático. Se llevaron a cabo cuatro fermentaciones con diferentes técnicas de alimentación y se confrontaron los resultados mediante simulación. Las técnicas estudiadas fueron alimentación puntual, alimentación continua-puntual y de alta densidad. La mayor concentración celular y factor de propagación se presentó con el cultivo de alta densidad. La simulación demostró que la alimentación continua o puntual afecta el comportamiento celular, ya sea sobre la velocidad específica y/o el factor estequiométrico Yx/s . Se encontró que la técnica de alta densidad aumenta el factor estequiométrico Yx/s.

    Beer yeast was propagated using batch culture, and a mathematical model was fitted to the resulting data. Intermittent, continuousintermittent, and high-density fed-batch techniques were used. The highest cell yield was found using the high density technique. Simulation also unveiled an effect of the feeding technique on cellular growth rate and yield. The high density technique increased the stoichiometric factor Yx/s.

  8. Biogas Production from Protein-Rich Biomass: Fed-Batch Anaerobic Fermentation of Casein and of Pig Blood and Associated Changes in Microbial Community Composition

    Science.gov (United States)

    Kovács, Etelka; Wirth, Roland; Maróti, Gergely; Bagi, Zoltán; Rákhely, Gábor; Kovács, Kornél L.

    2013-01-01

    It is generally accepted as a fact in the biogas technology that protein-rich biomass substrates should be avoided due to inevitable process inhibition. Substrate compositions with a low C/N ratio are considered difficult to handle and may lead to process failure, though protein-rich industrial waste products have outstanding biogas generation potential. This common belief has been challenged by using protein-rich substrates, i.e. casein and precipitated pig blood protein in laboratory scale continuously stirred mesophilic fed-batch biogas fermenters. Both substrates proved suitable for sustained biogas production (0.447 L CH4/g protein oDM, i.e. organic total solids) in high yield without any additives, following a period of adaptation of the microbial community. The apparent key limiting factors in the anaerobic degradation of these proteinaceous materials were the accumulation of ammonia and hydrogen sulfide. Changes in time in the composition of the microbiological community were determined by next-generation sequencing-based metagenomic analyses. Characteristic rearrangements of the biogas-producing community upon protein feeding and specific differences due to the individual protein substrates were recognized. The results clearly demonstrate that sustained biogas production is readily achievable, provided the system is well-characterized, understood and controlled. Biogas yields (0.45 L CH4/g oDM) significantly exceeding those of the commonly used agricultural substrates (0.25-0.28 L CH4/g oDM) were routinely obtained. The results amply reveal that these high-energy-content waste products can be converted to biogas, a renewable energy carrier with flexible uses that can replace fossil natural gas in its applications. Process control, with appropriate acclimation of the microbial community to the unusual substrate, is necessary. Metagenomic analysis of the microbial community by next-generation sequencing allows a precise determination of the alterations in

  9. Cellulase production by Penicillium funiculosum and its application in the hydrolysis of sugar cane bagasse for second generation ethanol production by fed batch operation.

    Science.gov (United States)

    Maeda, Roberto Nobuyuki; Barcelos, Carolina Araújo; Santa Anna, Lídia Maria Melo; Pereira, Nei

    2013-01-10

    This study aimed to produce a cellulase blend and to evaluate its application in a simultaneous saccharification and fermentation (SSF) process for second generation ethanol production from sugar cane bagasse. The sugar cane bagasse was subjected to pretreatments (diluted acid and alkaline), as for disorganizing the ligocellulosic complex, and making the cellulose component more amenable to enzymatic hydrolysis. The residual solid fraction was named sugar cane bagasse partially delignified cellulignin (PDC), and was used for enzyme production and ethanol fermentation. The enzyme production was performed in a bioreactor with two inoculum concentrations (5 and 10% v/v). The fermentation inoculated with higher inoculum size reduced the time for maximum enzyme production (from 72 to 48). The enzyme extract was concentrated using tangential ultrafiltration in hollow fiber membranes, and the produced cellulase blend was evaluated for its stability at 37 °C, operation temperature of the simultaneous SSF process, and at 50 °C, optimum temperature of cellulase blend activity. The cellulolytic preparation was stable for at least 300 h at both 37 °C and 50 °C. The ethanol production was carried out by PDC fed-batch SSF process, using the onsite cellulase blend. The feeding strategy circumvented the classic problems of diffusion limitations by diminishing the presence of a high solid:liquid ratio at any time, resulting in high ethanol concentration at the end of the process (100 g/L), which corresponded to a fermentation efficiency of 78% of the maximum obtainable theoretically. The experimental results led to the ratio of 380 L of ethanol per ton of sugar cane bagasse PDC. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Mathematical modeling of fed-batch fermentation of Schizochytrium sp. 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.

  11. Biogas production from protein-rich biomass: fed-batch anaerobic fermentation of casein and of pig blood and associated changes in microbial community composition.

    Directory of Open Access Journals (Sweden)

    Etelka Kovács

    Full Text Available It is generally accepted as a fact in the biogas technology that protein-rich biomass substrates should be avoided due to inevitable process inhibition. Substrate compositions with a low C/N ratio are considered difficult to handle and may lead to process failure, though protein-rich industrial waste products have outstanding biogas generation potential. This common belief has been challenged by using protein-rich substrates, i.e. casein and precipitated pig blood protein in laboratory scale continuously stirred mesophilic fed-batch biogas fermenters. Both substrates proved suitable for sustained biogas production (0.447 L CH4/g protein oDM, i.e. organic total solids in high yield without any additives, following a period of adaptation of the microbial community. The apparent key limiting factors in the anaerobic degradation of these proteinaceous materials were the accumulation of ammonia and hydrogen sulfide. Changes in time in the composition of the microbiological community were determined by next-generation sequencing-based metagenomic analyses. Characteristic rearrangements of the biogas-producing community upon protein feeding and specific differences due to the individual protein substrates were recognized. The results clearly demonstrate that sustained biogas production is readily achievable, provided the system is well-characterized, understood and controlled. Biogas yields (0.45 L CH4/g oDM significantly exceeding those of the commonly used agricultural substrates (0.25-0.28 L CH4/g oDM were routinely obtained. The results amply reveal that these high-energy-content waste products can be converted to biogas, a renewable energy carrier with flexible uses that can replace fossil natural gas in its applications. Process control, with appropriate acclimation of the microbial community to the unusual substrate, is necessary. Metagenomic analysis of the microbial community by next-generation sequencing allows a precise determination of the

  12. 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.

  13. Biodegradable poly-ε-caprolactone microcarriers for efficient production of human mesenchymal stromal cells and secreted cytokines in batch and fed-batch bioreactors.

    Science.gov (United States)

    Lam, Alan Tin-Lun; Li, Jian; Toh, Jessica Pei-Wen; Sim, Eileen Jia-Hui; Chen, Allen Kuan-Liang; Chan, Jerry Kok-Yen; Choolani, Mahesh; Reuveny, Shaul; Birch, William R; Oh, Steve Kah-Weng

    2017-03-01

    Large numbers of human mesenchymal stromal cells (MSCs) used for a variety of applications in tissue engineering and cell therapy can be generated by scalable expansion in a bioreactor using microcarriers (MCs) systems. However, the enzymatic digestion process needed to detach cells from the growth surface can affect cell viability and potentially the potency and differentiation efficiency. Thus, the main aim of our study was to develop biocompatible and biodegradable MCs that can support high MSC yields while maintaining their differentiation capability and potency. After cell expansion, the cells that covered MCs can be directly implanted in vivo without the need for cell harvesting or use of scaffold. Poly-ε-caprolactone (PCL) is known as a biocompatible and biodegradable material. However, it cannot be used for generation of MCs because its high density (1.14 g/cm 3 ) would exclude its applicability for suspension MCs in stirred reactors. In this article, we describe expansion and potency of MSCs propagated on low-density (1.06 g/cm 3 ) porous PCL MCs coated with extracellular matrices (LPCLs) in suspended stirred reactors. Using these LPCLs, cell yields of about 4 × 10 4 cells/cm 2 and 7- to 10-fold increases were obtained using four different MSC lines (bone marrow, cord blood, fetal and Wharton's jelly). These yields were comparable with those obtained using non-degradable MCs (Cytodex 3) and higher than two-dimensional monolayer (MNL) cultures. A fed-batch process, which demonstrated faster cell expansion (4.5 × 10 4 cells/cm 2 in 5 days as compared with 7 days in batch culture) and about 70% reduction in growth media usage, was developed and scaled up from 100-mL spinner flask to 1-L controlled bioreactor. Surface marker expression, trilineage differentiation and clonogenic potential of the MSCs expanded on LPCL were not affected. Cytokine secretion kinetics, which occurred mostly during late logarithmic phase, was usually comparable with

  14. Different cultivation methods to acclimatise ammonia-tolerant methanogenic consortia.

    Science.gov (United States)

    Tian, Hailin; Fotidis, Ioannis A; Mancini, Enrico; Angelidaki, Irini

    2017-05-01

    Bioaugmentation with ammonia tolerant-methanogenic consortia was proposed as a solution to overcome ammonia inhibition during anaerobic digestion process recently. However, appropriate technology to generate ammonia tolerant methanogenic consortia is still lacking. In this study, three basic reactors (i.e. batch, fed-batch and continuous stirred-tank reactors (CSTR)) operated at mesophilic (37°C) and thermophilic (55°C) conditions were assessed, based on methane production efficiency, incubation time, TAN/FAN (total ammonium nitrogen/free ammonia nitrogen) levels and maximum methanogenic activity. Overall, fed-batch cultivation was clearly the most efficient method compared to batch and CSTR. Specifically, by saving incubation time up to 150%, fed-batch reactors were acclimatised to nearly 2-fold higher FAN levels with a 37%-153% methanogenic activity improvement, compared to batch method. Meanwhile, CSTR reactors were inhibited at lower ammonia levels. Finally, specific methanogenic activity test showed that hydrogenotrophic methanogens were more active than aceticlastic methanogens in all FAN levels above 540mgNH 3 -NL -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Development of a two-stage feeding strategy based on the kind and level of feeding nutrients for improving fed-batch production of L-threonine by Escherichia coli.

    Science.gov (United States)

    Liu, Shuwen; Liang, Yong; Liu, Qian; Tao, Tongtong; Lai, Shujuan; Chen, Ning; Wen, Tingyi

    2013-01-01

    Fed-batch fermentation is the predominant method for industrial production of amino acids. In this study, we comprehensively investigated the effects of four kinds of feeding nutrients and developed an accurate optimization strategy for fed-batch production of L-threonine. The production of L-threonine was severely inhibited when cell growth ceased in the bath culture. Similarly, L-threonine production was also associated with cell growth in the carbon-, phosphate-, and sulfate-limited fed-batch cultures, but the accumulation of L-threonine was markedly increased because of the extended production time in the growth stage. Interestingly, auxotrophic amino acid (L-isoleucine)-limited feeding promoted L-threonine production over the non-growth phase. Metabolite analysis indicates that substantial production of acetate and glutamate and the resulting accumulation of ammonium may lead to the inhibition of L-threonine production. During the growth phase, the levels of L-isoleucine were accurately optimized by balancing cell growth and production with Pontryagin's maximum principle, basing on the relationship between the specific growth rate μ and specific production rate ρ. Furthermore, the depletion of L-isoleucine and phosphate at the end of the growth phase favored the synthesis of L-threonine in the subsequent non-growth phase. Combining the two-stage feeding profiles, the final L-threonine concentration and conversion rate were increased by 5.9- and 2.1-fold, respectively, compared to batch processes without feeding control. The identification of efficient feeding nutrient and the development of accurate feeding strategies provide potential guidelines for microbial production of amino acids.

  16. Chemometric analysis of in-line multi-wavelength fluorescence measurements obtained during cultivations with a lipase producing Aspergillus oryzae strain

    DEFF Research Database (Denmark)

    Haack, Martin Brian; Eliasson Lantz, Anna; Mortensen, P.P.

    2007-01-01

    The filamentous fungus, Aspergillus oryzae, was cultivated in batch and fed-batch cultivations in order to investigate the use of multi-wavelength fluorescence for monitoring course of events during filamentous fungi cultivations. The A. oryzae strain applied expressed a fungal lipase from...... Thermomyces lanuginosus. Spectra of multi-wavelength fluorescence were collected every 5 min with the BioView system (DELTA, Denmark) and both explorative and predictive models, correlating the fluorescence data with cell mass and lipase activity, were built. During the cultivations, A. oryzae displayed...

  17. Crystallization and diffraction analysis of thioredoxin reductase from Streptomyces coelicolor

    International Nuclear Information System (INIS)

    Koháryová, Michaela; Brynda, Jiří; Řezáčová, Pavlína; Kollárová, Marta

    2011-01-01

    Thioredoxin reductase from S. coelicolor was crystallized and diffraction data were collected to 2.4 Å resolution. Thioredoxin reductases are homodimeric flavoenzymes that catalyze the transfer of electrons from NADPH to oxidized thioredoxin substrate. Bacterial thioredoxin reductases represent a promising target for the development of new antibiotics. Recombinant thioredoxin reductase TrxB from Streptomyces coelicolor was crystallized using the hanging-drop vapour-diffusion method. X-ray diffraction data were collected from cryocooled crystals to 2.4 Å resolution using a synchrotron-radiation source. The crystals belonged to the primitive monoclinic space group P2 1 , with unit-cell parameters a = 82.9, b = 60.6, c = 135.4 Å, α = γ = 90.0, β = 96.5°

  18. Supplementation of serum free media with HT is not sufficient to restore growth properties of DHFR-/- cells in fed-batch processes - Implications for designing novel CHO-based expression platforms.

    Science.gov (United States)

    Florin, Lore; Lipske, Carolin; Becker, Eric; Kaufmann, Hitto

    2011-04-10

    DHFR-deficient CHO cells are the most commonly used host cells in the biopharmaceutical industry and over the years, individual substrains have evolved, some have been engineered with improved properties and platform technologies have been designed around them. Unexpectedly, we have observed that different DHFR-deficient CHO cells show only poor growth in fed-batch cultures even in HT supplemented medium, whereas antibody producer cells derived from these hosts achieved least 2-3 fold higher peak cell densities. Using a set of different expression vectors, we were able to show that this impaired growth performance was not due to the selection procedure possibly favouring fast growing clones, but a direct consequence of DHFR deficiency. Re-introduction of the DHFR gene reproducibly restored the growth phenotype to the level of wild-type CHO cells or even beyond which seemed to be dose-dependent. The requirement for a functional DHFR gene to achieve optimal growth under production conditions has direct implications for cell line generation since it suggests that changing to a selection system other than DHFR would require another CHO host which - especially for transgenic CHO strains and tailor-suited process platforms - this could mean significant investments and potential changes in product quality. In these cases, DHFR engineering of the current CHO-DG44 or DuxB11-based host could be an attractive alternative. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. High-titer lactic acid production from NaOH-pretreated corn stover by Bacillus coagulans LA204 using fed-batch simultaneous saccharification and fermentation under non-sterile condition.

    Science.gov (United States)

    Hu, Jinlong; Zhang, Zhenting; Lin, Yanxu; Zhao, Shumiao; Mei, Yuxia; Liang, Yunxiang; Peng, Nan

    2015-04-01

    Lactic acid (LA) is an important chemical with various industrial applications. Non-food feedstock is commercially attractive for use in LA production; however, efficient LA fermentation from lignocellulosic biomass resulting in both high yield and titer faces technical obstacles. In this study, the thermophilic bacterium Bacillus coagulans LA204 demonstrated considerable ability to ferment glucose, xylose, and cellobiose to LA. Importantly, LA204 produces LA from several NaOH-pretreated agro stovers, with remarkably high yields through simultaneous saccharification and fermentation (SSF). A fed-batch SSF process conducted at 50°C and pH 6.0, using a cellulase concentration of 30 FPU (filter paper unit)/g stover and 10 g/L yeast extract in a 5-L bioreactor, was developed to produce LA from 14.4% (w/w) NaOH-pretreated non-sterile corn stover. LA titer, yield, and average productivity reached 97.59 g/L, 0.68 g/g stover, and 1.63 g/L/h, respectively. This study presents a feasible process for lignocellulosic LA production from abundant agro stovers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Interspecies interactions stimulate diversification of the Streptomyces coelicolor secreted metabolome.

    Science.gov (United States)

    Traxler, Matthew F; Watrous, Jeramie D; Alexandrov, Theodore; Dorrestein, Pieter C; Kolter, Roberto

    2013-08-20

    Soils host diverse microbial communities that include filamentous actinobacteria (actinomycetes). These bacteria have been a rich source of useful metabolites, including antimicrobials, antifungals, anticancer agents, siderophores, and immunosuppressants. While humans have long exploited these compounds for therapeutic purposes, the role these natural products may play in mediating interactions between actinomycetes has been difficult to ascertain. As an initial step toward understanding these chemical interactions at a systems level, we employed the emerging techniques of nanospray desorption electrospray ionization (NanoDESI) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) imaging mass spectrometry to gain a global chemical view of the model bacterium Streptomyces coelicolor interacting with five other actinomycetes. In each interaction, the majority of secreted compounds associated with S. coelicolor colonies were unique, suggesting an idiosyncratic response from S. coelicolor. Spectral networking revealed a family of unknown compounds produced by S. coelicolor during several interactions. These compounds constitute an extended suite of at least 12 different desferrioxamines with acyl side chains of various lengths; their production was triggered by siderophores made by neighboring strains. Taken together, these results illustrate that chemical interactions between actinomycete bacteria exhibit high complexity and specificity and can drive differential secondary metabolite production. Actinomycetes, filamentous actinobacteria from the soil, are the deepest natural source of useful medicinal compounds, including antibiotics, antifungals, and anticancer agents. There is great interest in developing new strategies that increase the diversity of metabolites secreted by actinomycetes in the laboratory. Here we used several metabolomic approaches to examine the chemicals made by these bacteria when grown in pairwise coculture. We found that

  1. Comparative genomic hybridizations reveal absence of large Streptomyces coelicolor genomic islands in Streptomyces lividans

    OpenAIRE

    Jayapal, Karthik P; Lian, Wei; Glod, Frank; Sherman, David H; Hu, Wei-Shou

    2007-01-01

    Abstract Background The genomes of Streptomyces coelicolor and Streptomyces lividans bear a considerable degree of synteny. While S. coelicolor is the model streptomycete for studying antibiotic synthesis and differentiation, S. lividans is almost exclusively considered as the preferred host, among actinomycetes, for cloning and expression of exogenous DNA. We used whole genome microarrays as a comparative genomics tool for identifying the subtle differences between these two chromosomes. Res...

  2. TOF-SIMS investigation of Streptomyces coelicolor, a mycelial bacterium

    International Nuclear Information System (INIS)

    Vaidyanathan, Seetharaman; Fletcher, John S.; Lockyer, Nicholas P.; Vickerman, John C.

    2008-01-01

    Streptomyces coelicolor is a mycelial microorganism that produces several secondary metabolites, including antibiotics. The physiology of the organism has largely been investigated in liquid cultures due to ease of monitoring different physiological parameters and more homogeneous culture conditions. However, solid cultures reflect the natural physiology of the microorganism better, given that in its natural state it grows in the soil. Imaging mass spectrometry with TOF-SIMS and C 60 + primary ion beams offers a potential route to studying chemical changes at the molecular level, both intracellular and extracellular that can help in understanding the natural physiology of the microorganism. Here, we report the application of the technique for studying the lateral distribution of the chemical species detected in a population, grown in both liquid and solid cultures. The capability of the technique for studying biological systems with minimal system intervention is demonstrated.

  3. TOF-SIMS investigation of Streptomyces coelicolor, a mycelial bacterium

    Science.gov (United States)

    Vaidyanathan, Seetharaman; Fletcher, John S.; Lockyer, Nicholas P.; Vickerman, John C.

    2008-12-01

    Streptomyces coelicolor is a mycelial microorganism that produces several secondary metabolites, including antibiotics. The physiology of the organism has largely been investigated in liquid cultures due to ease of monitoring different physiological parameters and more homogeneous culture conditions. However, solid cultures reflect the natural physiology of the microorganism better, given that in its natural state it grows in the soil. Imaging mass spectrometry with TOF-SIMS and C 60+ primary ion beams offers a potential route to studying chemical changes at the molecular level, both intracellular and extracellular that can help in understanding the natural physiology of the microorganism. Here, we report the application of the technique for studying the lateral distribution of the chemical species detected in a population, grown in both liquid and solid cultures. The capability of the technique for studying biological systems with minimal system intervention is demonstrated.

  4. Synthetic Promoter Library for Modulation of Actinorhodin Production in Streptomyces coelicolor A3(2)

    Science.gov (United States)

    Sohoni, Sujata Vijay; Fazio, Alessandro; Workman, Christopher T.; Mijakovic, Ivan; Lantz, Anna Eliasson

    2014-01-01

    The objective of this study was the application of the synthetic promoter library (SPL) technology for modulation of actinorhodin production in Streptomyces coelicolor A3(2). The SPL technology was used to optimize the expression of a pathway specific positive transcriptional regulator ActII orf4, which activates the transcription of the S. coelicolor actinorhodin biosynthetic gene cluster. The native actII orf4 promoter was replaced with synthetic promoters, generating a S. coelicolor library with a broad range of expression levels of actII orf4. The resulting library was screened based on the yield of actinorhodin. Selected strains were further physiologically characterized. One of the strains from the library, ScoSPL20, showed considerably higher yield of actinorhodin and final actinorhodin titer, compared to S. coelicolor wild type and S. coelicolor with actII orf4 expressed from a strong constitutive promoter. ScoSPL20 demonstrated exceptional productivity despite having a comparatively weak expression from the promoter. Interestingly, the ScoSPL20 promoter was activated at a much earlier stage of growth compared to the wild type, demonstrating the advantage of fine-tuning and temporal tuning of gene expression in metabolic engineering. Transcriptome studies were performed in exponential and actinorhodin-producing phase of growth to compare gene expression between ScoSPL20 and the wild type. To our knowledge, this is the first successful application of the SPL technology for secondary metabolite production in filamentous bacteria. PMID:24963940

  5. Synthetic Promoter Library for Modulation of Actinorhodin Production in Streptomyces coelicolor A3(2)

    DEFF Research Database (Denmark)

    Sohoni, Sujata Vijay; Fazio, Alessandro; Workman, Christopher

    2014-01-01

    The objective of this study was the application of the synthetic promoter library (SPL) technology for modulation of actinorhodin production in Streptomyces coelicolor A3(2). The SPL technology was used to optimize the expression of a pathway specific positive transcriptional regulator Actll orf4...... constitutive promoter. ScoSPL20 demonstrated exceptional productivity despite having a comparatively weak expression from the promoter. Interestingly, the ScoSPL20 promoter was activated at a much earlier stage of growth compared to the wild type, demonstrating the advantage of fine-tuning and temporal tuning......, which activates the transcription of the S. coelicolor actinorhodin biosynthetic gene cluster. The native actll orf4 promoter was replaced with synthetic promoters, generating a S. coelicolor library with a broad range of expression levels of actll orf4. The resulting library was screened based...

  6. Secondary Metabolites Produced during the Germination of Streptomyces coelicolor

    Directory of Open Access Journals (Sweden)

    Matouš Čihák

    2017-12-01

    Full Text Available Spore awakening is a series of actions that starts with purely physical processes and continues via the launching of gene expression and metabolic activities, eventually achieving a vegetative phase of growth. In spore-forming microorganisms, the germination process is controlled by intra- and inter-species communication. However, in the Streptomyces clade, which is capable of developing a plethora of valuable compounds, the chemical signals produced during germination have not been systematically studied before. Our previously published data revealed that several secondary metabolite biosynthetic genes are expressed during germination. Therefore, we focus here on the secondary metabolite production during this developmental stage. Using high-performance liquid chromatography-mass spectrometry, we found that the sesquiterpenoid antibiotic albaflavenone, the polyketide germicidin A, and chalcone are produced during germination of the model streptomycete, S. coelicolor. Interestingly, the last two compounds revealed an inhibitory effect on the germination process. The secondary metabolites originating from the early stage of microbial growth may coordinate the development of the producer (quorum sensing and/or play a role in competitive microflora repression (quorum quenching in their nature environments.

  7. Formation and dispersion of mycelial pellets of Streptomyces coelicolor A3(2).

    Science.gov (United States)

    Kim, Yul-Min; Kim, Jae-heon

    2004-03-01

    The pellets from a culture of Streptomyces coelicolor A3(2) that were submerged shaken were disintegrated into numerous hyphal fragments by DNase treatment. The pellets were increasingly dispersed by hyaluronidase treatment, and mycelial fragments were easily detached from the pellets. The submerged mycelium grew by forming complexes with calcium phosphate precipitates or kaolin, a soil particle. Therefore, the pellet formation of Streptomyces coelicolor A3(2) can be considered a biofilm formation, including the participation of adhesive extracellular polymers and the insoluble substrates.

  8. The Level of AdpA Directly Affects Expression of Developmental Genes in Streptomyces coelicolor ▿ †

    OpenAIRE

    Wolański, Marcin; Donczew, Rafał; Kois-Ostrowska, Agnieszka; Masiewicz, Paweł; Jakimowicz, Dagmara; Zakrzewska-Czerwińska, Jolanta

    2011-01-01

    AdpA is a key regulator of morphological differentiation in Streptomyces. In contrast to Streptomyces griseus, relatively little is known about AdpA protein functions in Streptomyces coelicolor. Here, we report for the first time the translation accumulation profile of the S. coelicolor adpA (adpASc) gene; the level of S. coelicolor AdpA (AdpASc) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hour...

  9. Plasticity of Streptomyces coelicolor membrane composition under different growth conditions and during development

    Directory of Open Access Journals (Sweden)

    Mario eSandoval-Calderón

    2015-12-01

    Full Text Available Streptomyces coelicolor is a model actinomycete that is well known for the diversity of its secondary metabolism and its complex life cycle. As a soil inhabitant, it is exposed to heterogeneous and frequently changing environmental circumstances. In the present work, we studied the effect of diverse growth conditions and phosphate depletion on its lipid profile and the relationship between membrane lipid composition and development in S. coelicolor. The lipid profile from cultures grown on solid media, which is closer to the natural habitat of this microorganism, does not resemble the previously reported lipid composition from liquid grown cultures of S. coelicolor. Wide variations were also observed across different media, growth phases, and developmental stages indicating active membrane remodeling. Ornithine lipids (OL are phosphorus-free polar lipids that were accumulated mainly during sporulation stages, but were also major components of the membrane under phosphorus limitation. In contrast, phosphatidylethanolamine, which had been reported as one of the major polar lipids in the genus Streptomyces, is almost absent under these conditions. We identified one of the genes responsible for the synthesis of OL (SCO0921 and found that its inactivation causes the absence of OL, precocious morphological development and actinorhodin production. Our observations indicate a remarkable plasticity of the membrane composition in this bacterial species, reveal a higher metabolic complexity than expected, and suggest a relationship between cytoplasmic membrane components and the differentiation programs in S. coelicolor.

  10. Interactions between Streptomyces coelicolor and Bacillus subtilis: Role of surfactants in raising aerial structures.

    Science.gov (United States)

    Straight, Paul D; Willey, Joanne M; Kolter, Roberto

    2006-07-01

    Using mixed-species cultures, we have undertaken a study of interactions between two common spore-forming soil bacteria, Bacillus subtilis and Streptomyces coelicolor. Our experiments demonstrate that the development of aerial hyphae and spores by S. coelicolor is inhibited by surfactin, a lipopeptide surfactant produced by B. subtilis. Current models of aerial development by sporulating bacteria and fungi postulate a role for surfactants in reducing surface tension at air-liquid interfaces, thereby removing the major barrier to aerial growth. S. coelicolor produces SapB, an amphipathic peptide that is surface active and required for aerial growth on certain media. Loss of aerial hyphae in developmental mutants can be rescued by addition of purified SapB. While a surfactant from a fungus can substitute for SapB in a mutant that lacks aerial hyphae, not all surfactants have this effect. We show that surfactin is required for formation of aerial structures on the surface of B. subtilis colonies. However, in contrast to this positive role, our experiments reveal that surfactin acts antagonistically by arresting S. coelicolor aerial development and causing altered expression of developmental genes. Our observations support the idea that surfactants function specifically for a given organism regardless of their shared ability to reduce surface tension. Production of surfactants with antagonistic activity could provide a powerful competitive advantage during surface colonization and in competition for resources.

  11. Global Features of Gene Expression on the Proteome and Transcriptome Levels in S. coelicolor during Germination

    Czech Academy of Sciences Publication Activity Database

    Straková, Eva; Bobek, Jan; Ziková, Alice; Vohradský, Jiří

    2013-01-01

    Roč. 8, č. 9 (2013) E-ISSN 1932-6203 R&D Projects: GA ČR GAP302/11/0229; GA ČR GAP302/10/0468 Institutional support: RVO:61388971 Keywords : Streptomycetes * Gene expression * s. coelicolor Subject RIV: EE - Microbiology, Virology Impact factor: 3.534, year: 2013

  12. Effect of Protein Kinase Inhibitors on Protein Phosphorylation and Germination of Aerial Spores from Streptomyces coelicolor

    Czech Academy of Sciences Publication Activity Database

    Palečková, Petra; Kontrová, K.; Kofroňová, Olga; Bobek, Jan; Benada, Oldřich; Mikulík, Karel

    2007-01-01

    Roč. 52, č. 3 (2007), s. 215-222 ISSN 0015-5632 R&D Projects: GA ČR GA203/05/0106 Institutional research plan: CEZ:AV0Z50200510 Keywords : streptomyces coelicolor * protein kinase * phosphoprotein Subject RIV: EE - Microbiology, Virology Impact factor: 0.989, year: 2007

  13. Noncoding RNA of Glutamine Synthetase I Modulates Antibiotic Production in Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    D'Alia, Davide; Nieselt, Kay; Steigele, Stephan; Mueller, Jonas; Verburg, Ilse; Takano, Eriko; Alia, Davide D’; Müller, Jonas

    Overexpression of antisense chromosomal cis-encoded noncoding RNAss (ncRNAs) in glutamine synthetase I resulted in a decrease in growth, protein synthesis, and antibiotic production in Streptomyces coelicolor. In addition, we predicted 3,597 cis-encoded ncRNAs and validated 13 of them

  14. Discovery, characterization, and kinetic analysis of an alditol oxidase from streptomyces coelicolor

    NARCIS (Netherlands)

    Heuts, Dominic P. H. M.; van Hellemond, Erik W.; Janssen, Dick B.; Fraaije, Marco W.

    2007-01-01

    A gene encoding an alditol oxidase was found in the genome of Streptomyces coelicolor A3(2). This newly identified oxidase, AldO, was expressed at extremely high levels in Escherichia coli when fused to maltose-binding protein. AldO is a soluble monomeric flavoprotein with subunits of 45.1 kDa, each

  15. Production of actinorhodin-related ''blue pigments'' by Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    Bystrykh, LV; FernandezMoreno, MA; Herrema, JK; Malpartida, F; Hopwood, DA; Dijkhuizen, L

    The genetically well-known strain Streptomyces coelicolor A3(2) produces the pH indicator (red/blue) antibiotic actinorhodin, but not all the ''blue pigment'' produced by this strain is actinorhodin. When the organism was subjected to various nutrient limitations (ammonium, nitrate, phosphate, or

  16. Antibiotic Overproduction in Steptomyces coelicolor A3(2) Mediated by Phosphofructokinase Deletion

    DEFF Research Database (Denmark)

    Borodina, Irina; Siebring, Jeroen; Zhang, Jie

    2008-01-01

    the primary metabolism. High level production of antibiotics in streptomycetes therefore requires engineering of the primary metabolism. Here we demonstrate this by targeting a key enzyme in glycolysis, phosphofructokinase, leading to improved antibiotic production in Streptomyces coelicolor A3(2). Deletion...... of pfkA2 (SCO5426), one of three annotated pfkA homologues in S. coelicolor A3(2), resulted in a higher production of the pigmented antibiotics actinorhodin and undecylprodigiosin. The pfkA2 deletion strain had an increased carbon flux through the pentose phosphate pathway, as measured by C-13 metabolic....... Through genome-scale metabolic model simulations, we predicted that decreased phosphofructokinase activity leads to an increase in pentose phosphate pathway flux and in flux to pigmented antibiotics and pyruvate. Integrated analysis of gene expression data using a genome-scale metabolic model further...

  17. Prioritizing orphan proteins for further study using phylogenomics and gene expression profiles in Streptomyces coelicolor

    Directory of Open Access Journals (Sweden)

    Takano Eriko

    2011-09-01

    Full Text Available Abstract Background Streptomyces coelicolor, a model organism of antibiotic producing bacteria, has one of the largest genomes of the bacterial kingdom, including 7825 predicted protein coding genes. A large number of these genes, nearly 34%, are functionally orphan (hypothetical proteins with unknown function. However, in gene expression time course data, many of these functionally orphan genes show interesting expression patterns. Results In this paper, we analyzed all functionally orphan genes of Streptomyces coelicolor and identified a list of "high priority" orphans by combining gene expression analysis and additional phylogenetic information (i.e. the level of evolutionary conservation of each protein. Conclusions The prioritized orphan genes are promising candidates to be examined experimentally in the lab for further characterization of their function.

  18. Transcription analysis of the Streptomyces coelicolor A3(2) rrnA operon

    DEFF Research Database (Denmark)

    van Wezel, G P; Krab, I M; Douthwaite, S

    1994-01-01

    Transcription start sites and processing sites of the Streptomyces coelicolor A3(2) rrnA operon have been investigated by a combination of in vivo and in vitro transcription analyses. The data from these approaches are consistent with the existence of four in vivo transcription sites, corresponding...... to the promoters P1-P4. The transcription start sites are located at -597, -416, -334 and -254 relative to the start of the 16S rRNA gene. Two putative processing sites were identified, one of which is similar to a sequence reported earlier in S. coelicolor and other eubacteria. The P1 promoter is likely...... common to P2, P3 and P4 is not similar to any other known consensus promoter sequence. In fast-growing mycelium, P2 appears to be the most frequently used promoter. Transcription from all of the rrnA promoters decreased during the transition from exponential to stationary phase, although transcription...

  19. Bioreactors for high cell density and continuous multi-stage cultivations: options for process intensification in cell culture-based viral vaccine production.

    Science.gov (United States)

    Tapia, Felipe; Vázquez-Ramírez, Daniel; Genzel, Yvonne; Reichl, Udo

    2016-03-01

    With an increasing demand for efficacious, safe, and affordable vaccines for human and animal use, process intensification in cell culture-based viral vaccine production demands advanced process strategies to overcome the limitations of conventional batch cultivations. However, the use of fed-batch, perfusion, or continuous modes to drive processes at high cell density (HCD) and overextended operating times has so far been little explored in large-scale viral vaccine manufacturing. Also, possible reductions in cell-specific virus yields for HCD cultivations have been reported frequently. Taking into account that vaccine production is one of the most heavily regulated industries in the pharmaceutical sector with tough margins to meet, it is understandable that process intensification is being considered by both academia and industry as a next step toward more efficient viral vaccine production processes only recently. Compared to conventional batch processes, fed-batch and perfusion strategies could result in ten to a hundred times higher product yields. Both cultivation strategies can be implemented to achieve cell concentrations exceeding 10(7) cells/mL or even 10(8) cells/mL, while keeping low levels of metabolites that potentially inhibit cell growth and virus replication. The trend towards HCD processes is supported by development of GMP-compliant cultivation platforms, i.e., acoustic settlers, hollow fiber bioreactors, and hollow fiber-based perfusion systems including tangential flow filtration (TFF) or alternating tangential flow (ATF) technologies. In this review, these process modes are discussed in detail and compared with conventional batch processes based on productivity indicators such as space-time yield, cell concentration, and product titers. In addition, options for the production of viral vaccines in continuous multi-stage bioreactors such as two- and three-stage systems are addressed. While such systems have shown similar virus titers compared to

  20. Robotic platform for parallelized cultivation and monitoring of microbial growth parameters in microwell plates.

    Science.gov (United States)

    Knepper, Andreas; Heiser, Michael; Glauche, Florian; Neubauer, Peter

    2014-12-01

    The enormous variation possibilities of bioprocesses challenge process development to fix a commercial process with respect to costs and time. Although some cultivation systems and some devices for unit operations combine the latest technology on miniaturization, parallelization, and sensing, the degree of automation in upstream and downstream bioprocess development is still limited to single steps. We aim to face this challenge by an interdisciplinary approach to significantly shorten development times and costs. As a first step, we scaled down analytical assays to the microliter scale and created automated procedures for starting the cultivation and monitoring the optical density (OD), pH, concentrations of glucose and acetate in the culture medium, and product formation in fed-batch cultures in the 96-well format. Then, the separate measurements of pH, OD, and concentrations of acetate and glucose were combined to one method. This method enables automated process monitoring at dedicated intervals (e.g., also during the night). By this approach, we managed to increase the information content of cultivations in 96-microwell plates, thus turning them into a suitable tool for high-throughput bioprocess development. Here, we present the flowcharts as well as cultivation data of our automation approach. © 2014 Society for Laboratory Automation and Screening.

  1. Development of bioprocess for high density cultivation yield of the probiotic Bacillus coagulans and its spores

    Directory of Open Access Journals (Sweden)

    Kavita R. Pandey

    2016-09-01

    Full Text Available Bacillus coagulans is a spore forming lactic acid bacterium. Spore forming bacteria, have been extensively studied and commercialized as probiotics. Probiotics are produced by fermentation technology. There is a limitation to biomass produced by conventional modes of fermentation. With the great demand generated by range of probiotic products, biomass is becoming very valuable for several pharmaceutical, dairy and probiotic companies. Thus, there is a need to develop high cell density cultivation processes for enhanced biomass accumulation. The bioprocess development was carried out in 6.6 L bench top lab scale fermentor. Four different cultivation strategies were employed to develop a bioprocess for higher growth and sporulation efficiencies of probiotic B. coagulans. Batch fermentation of B. coagulans yielded 18 g L-1 biomass (as against 8.0 g L-1 productivity in shake flask with 60% spore efficiency. Fed-batch cultivation was carried out for glucose, which yielded 25 g L-1 of biomass. C/N ratio was very crucial in achieving higher spore titres. Maximum biomass yield recorded was 30 g L-1, corresponding to 3.8 × 1011 cells mL-1 with 81% of cells in sporulated stage. The yield represents increment of 85 times the productivity and 158 times the spore titres relative to the highest reported values for high density cultivation of B. coagulans.

  2. Identification of new developmentally regulated genes involved in Streptomyces coelicolor sporulation.

    Science.gov (United States)

    Salerno, Paola; Persson, Jessica; Bucca, Giselda; Laing, Emma; Ausmees, Nora; Smith, Colin P; Flärdh, Klas

    2013-12-05

    The sporulation of aerial hyphae of Streptomyces coelicolor is a complex developmental process. Only a limited number of the genes involved in this intriguing morphological differentiation programme are known, including some key regulatory genes. The aim of this study was to expand our knowledge of the gene repertoire involved in S. coelicolor sporulation. We report a DNA microarray-based investigation of developmentally controlled gene expression in S. coelicolor. By comparing global transcription patterns of the wild-type parent and two mutants lacking key regulators of aerial hyphal sporulation, we found a total of 114 genes that had significantly different expression in at least one of the two mutants compared to the wild-type during sporulation. A whiA mutant showed the largest effects on gene expression, while only a few genes were specifically affected by whiH mutation. Seven new sporulation loci were investigated in more detail with respect to expression patterns and mutant phenotypes. These included SCO7449-7451 that affect spore pigment biogenesis; SCO1773-1774 that encode an L-alanine dehydrogenase and a regulator-like protein and are required for maturation of spores; SCO3857 that encodes a protein highly similar to a nosiheptide resistance regulator and affects spore maturation; and four additional loci (SCO4421, SCO4157, SCO0934, SCO1195) that show developmental regulation but no overt mutant phenotype. Furthermore, we describe a new promoter-probe vector that takes advantage of the red fluorescent protein mCherry as a reporter of cell type-specific promoter activity. Aerial hyphal sporulation in S. coelicolor is a technically challenging process for global transcriptomic investigations since it occurs only as a small fraction of the colony biomass and is not highly synchronized. Here we show that by comparing a wild-type to mutants lacking regulators that are specifically affecting processes in aerial hypha, it is possible to identify previously

  3. Production of Actinorhodin-Related ‘‘Blue Pigments’’ by Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    Bystrykh, Leonid V.; Fernández-Moreno, Miguel A.; Herrema, Jan K.; Malpartida, Francisco; Hopwood, David A.; Dijkhuizen, Lubbert

    1996-01-01

    The genetically well-known strain Streptomyces coelicolor A3(2) produces the pH indicator (red/blue) antibiotic actinorhodin, but not all the ‘‘blue pigment’’ produced by this strain is actinorhodin. When the organism was subjected to various nutrient limitations (ammonium, nitrate, phosphate, or

  4. Comparative genomics of Streptomyces avermitilis, Streptomyces cattleya, Streptomyces maritimus and Kitasatospora aureofaciens using a Streptomyces coelicolor microarray system

    NARCIS (Netherlands)

    Hsiao, Nai-hua; Kirby, Ralph

    DNA/DNA microarray hybridization was used to compare the genome content of Streptomyces avermitilis, Streptomyces cattleya, Streptomyces maritimus and Kitasatospora aureofaciens with that of Streptomyces coelicolor A3(2). The array data showed an about 93% agreement with the genome sequence data

  5. Expanding the chemical space for natural products by Aspergillus-Streptomyces co-cultivation and biotransformation

    Science.gov (United States)

    Wu, Changsheng; Zacchetti, Boris; Ram, Arthur F.J.; van Wezel, Gilles P.; Claessen, Dennis; Hae Choi, Young

    2015-01-01

    Actinomycetes and filamentous fungi produce a wide range of bioactive compounds, with applications as antimicrobials, anticancer agents or agrochemicals. Their genomes contain a far larger number of gene clusters for natural products than originally anticipated, and novel approaches are required to exploit this potential reservoir of new drugs. Here, we show that co-cultivation of the filamentous model microbes Streptomyces coelicolor and Aspergillus niger has a major impact on their secondary metabolism. NMR-based metabolomics combined with multivariate data analysis revealed several compounds that correlated specifically to co-cultures, including the cyclic dipeptide cyclo(Phe-Phe) and 2-hydroxyphenylacetic acid, both of which were produced by A. niger in response to S. coelicolor. Furthermore, biotransformation studies with o-coumaric acid and caffeic acid resulted in the production of the novel compounds (E)-2-(3-hydroxyprop-1-en-1-yl)-phenol and (2E,4E)-3-(2-carboxy-1-hydroxyethyl)-2,4-hexadienedioxic acid, respectively. This highlights the utility of microbial co-cultivation combined with NMR-based metabolomics as an efficient pipeline for the discovery of novel natural products. PMID:26040782

  6. Biomass-derived molecules modulate the behavior of Streptomyces coelicolor for antibiotic production.

    Science.gov (United States)

    Bhatia, Shashi Kant; Lee, Bo-Rahm; Sathiyanarayanan, Ganesan; Song, Hun Seok; Kim, Junyoung; Jeon, Jong-Min; Yoon, Jeong-Jun; Ahn, Jungoh; Park, Kyungmoon; Yang, Yung-Hun

    2016-12-01

    Various chemicals, i.e., furfural, vanillin, 4-hydroxybenzaldehyde and acetate produced during the pretreatment of biomass affect microbial fermentation. In this study, effect of vanillin, 4-hydroxybenzaldehyde and acetate on antibiotic production in Streptomyces coelicolor is investigated. IC 50 value of vanillin, 4-hydroxybenzaldehyde and acetate was recorded as 5, 11.3 and 115 mM, respectively. Vanillin was found as a very effective molecule, and it completely abolished antibiotic (undecylprodigiosin and actinorhodin) production at 1 mM concentration, while 4-hydroxybenzaldehyde and acetate have little effect. Microscopic analysis with field emission scanning electron microscopy (FESEM) showed that addition of vanillin inhibits mycelia formation and increases differentiation of S. coelicolor cells. Vanillin increases expression of genes responsible for sporulation (ssgA) and decreases expression of antibiotic transcriptional regulator (redD and actII-orf4), while it has no effect on genes related to the mycelia formation (bldA and bldN) and quorum sensing (scbA and scbR). Vanillin does not affect the glycolysis process, but may affect acetate and pyruvate accumulation which leads to increase in fatty acid accumulation. The production of antibiotics using biomass hydrolysates can be quite complex due to the presence of exogenous chemicals such as furfural and vanillin, and needs further detailed study.

  7. Fed-Batch Feeding Strategies for Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John

    2014-01-01

    of the differences in the interfacial and bulk concentrations of the enzyme. The model is then used to evaluate various feeding strategies to improve the enzymatic biodiesel production. The feeding strategies investigated, gave insight into how the methanol should be fed to potentially mitigate enzyme deactivation...... while improving the biodiesel yield. The best experimental results gave a yield of 703 .76 g FAME L-1 and a reactor productivity of 28.12 g FAME L-1 h-1. In comparison, to reach the same yield, the optimised two step feeding strategy took 6.25 hours less, which equates to an increase the reactor...

  8. Deletion of the signalling molecule synthase ScbA has pleiotropic effects on secondary metabolite biosynthesis, morphological differentiation and primary metabolism in Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    D'Alia, Davide; Eggle, D.; Nieselt, K.; Hu, W.-S.; Breitling, R.; Takano, E.

    2011-01-01

    Streptomycetes have high biotechnological relevance as producers of diverse metabolites widely used in medical and agricultural applications. The biosynthesis of these metabolites is controlled by signalling molecules, gamma-butyrolactones, that act as bacterial hormones. In Streptomyces coelicolor,

  9. Community proteomics provides functional insight into polyhydroxyalkanoate production by a mixed microbial culture cultivated on fermented dairy manure.

    Science.gov (United States)

    Hanson, Andrea J; Guho, Nicholas M; Paszczynski, Andrzej J; Coats, Erik R

    2016-09-01

    Polyhydroxyalkanoates (PHAs) are bio-based, biodegradable polyesters that can be produced from organic-rich waste streams using mixed microbial cultures (MMCs). To maximize PHA production, MMCs are enriched for bacteria with a high polymer storage capacity through the application of aerobic dynamic feeding (ADF) in a sequencing batch reactor (SBR), which consequently induces a feast-famine metabolic response. Though the feast-famine response is generally understood empirically at a macro-level, the molecular level is less refined. The objective of this study was to investigate the microbial community composition and proteome profile of an enriched MMC cultivated on fermented dairy manure. The enriched MMC exhibited a feast-famine response and was capable of producing up to 40 % (wt. basis) PHA in a fed-batch reactor. High-throughput 16S rRNA gene sequencing revealed a microbial community dominated by Meganema, a known PHA-producing genus not often observed in high abundance in enrichment SBRs. The application of the proteomic methods two-dimensional electrophoresis and LC-MS/MS revealed PHA synthesis, energy generation, and protein synthesis prominently occurring during the feast phase, corroborating bulk solution variable observations and theoretical expectations. During the famine phase, nutrient transport, acyl-CoA metabolism, additional energy generation, and housekeeping functions were more pronounced, informing previously under-determined MMC functionality under famine conditions. During fed-batch PHA production, acetyl-CoA acetyltransferase and PHA granule-bound phasin proteins were in increased abundance relative to the SBR, supporting the higher PHA content observed. Collectively, the results provide unique microbial community structural and functional insight into feast-famine PHA production from waste feedstocks using MMCs.

  10. Low molecular weight protein tyrosine phosphatases control antibiotic production in Streptomyces coelicolor A3(2)

    DEFF Research Database (Denmark)

    Sohoni, Sujata Vijay; Lieder, Sarah; Bapat, Prashant Madhusudhan

    2014-01-01

    3700 was established usingpara-nitrophenyl phosphate and the tyrosine-phosphorylated protein PtkA from Bacillus subtilis as substrates. Theoptimum pH for the Sco3700 phosphatase activity was 6.8, and KM for pNPP was 14.3 mM compared to pH 6.0and KM0.75 mM for PtpA. The potential of Sco3700...... of ACT in the ptpA over expression strain. Furthermore, a significantly earlier onset of ACT productionwas observed when ptpA was over expressed. Sco3700 overexpression had a pleiotropic effect on the cell, and thestrain exhibited lower productivities and final concentrations of antibiotics. We conclude...... that Sco3700 is indeed atyrosine phosphatase, and it contributes to regulation of antibiotic production in S. coelicolor affecting the timing ofonset of the antibiotic production...

  11. Uncovering genes with divergent mRNA-protein dynamics in Streptomyces coelicolor.

    Directory of Open Access Journals (Sweden)

    Karthik P Jayapal

    2008-05-01

    Full Text Available Many biological processes are intrinsically dynamic, incurring profound changes at both molecular and physiological levels. Systems analyses of such processes incorporating large-scale transcriptome or proteome profiling can be quite revealing. Although consistency between mRNA and proteins is often implicitly assumed in many studies, examples of divergent trends are frequently observed. Here, we present a comparative transcriptome and proteome analysis of growth and stationary phase adaptation in Streptomyces coelicolor, taking the time-dynamics of process into consideration. These processes are of immense interest in microbiology as they pertain to the physiological transformations eliciting biosynthesis of many naturally occurring therapeutic agents. A shotgun proteomics approach based on mass spectrometric analysis of isobaric stable isotope labeled peptides (iTRAQ enabled identification and rapid quantification of approximately 14% of the theoretical proteome of S. coelicolor. Independent principal component analyses of this and DNA microarray-derived transcriptome data revealed that the prominent patterns in both protein and mRNA domains are surprisingly well correlated. Despite this overall correlation, by employing a systematic concordance analysis, we estimated that over 30% of the analyzed genes likely exhibited significantly divergent patterns, of which nearly one-third displayed even opposing trends. Integrating this data with biological information, we discovered that certain groups of functionally related genes exhibit mRNA-protein discordance in a similar fashion. Our observations suggest that differences between mRNA and protein synthesis/degradation mechanisms are prominent in microbes while reaffirming the plausibility of such mechanisms acting in a concerted fashion at a protein complex or sub-pathway level.

  12. pH-Induced interfacial properties of Chaplin E from Streptomyces coelicolor.

    Science.gov (United States)

    Dokouhaki, Mina; Hung, Andrew; Prime, Emma L; Qiao, Greg G; Day, Li; Gras, Sally L

    2017-12-01

    Chaplin E, or Chp E, is a surface active peptide secreted by Streptomyces coelicolor that adopts different structures depending on solution pH but the effect of these structures on the interfacial properties of Chp E is not known. In experiments paired with simulations, Chp E was found to display pH-dependent interfacial assembly and surface activity. At pH 3.0, Chp E formed an ordered non-amyloidal interfacial film with high surface activity; while at pH 10.0, Chp E self-assembled into a heterogeneous film containing randomly arranged fibrils at the interface that was less surface active compared to the film formed at pH 3.0. In simulations at pH 10.0, Chp E molecules showed a higher propensity for dimerization within the solution phase, lower rate of adsorption to the interface and tighter inter-molecular associations at the interface, consistent with the lower surface activity and smaller interfacial area coverage per molecule measured at this pH compared to at pH 3.0. A model is presented for the role of Chp E in the developmental differentiation of Streptomyces coelicolor, where Chp E contributes to changes in surface tension at low pH and the formation of fibrils on the surface of aerial hyphae at high pH. Our data also suggest Chp E could be a promising surface active agent with functional activity that can be controlled by pH. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Role of GntR Family Regulatory Gene SCO1678 in Gluconate Metabolism in Streptomyces coelicolor M145

    Directory of Open Access Journals (Sweden)

    Olga Tsypik

    2017-01-01

    Full Text Available Here we report functional characterization of the Streptomyces coelicolor M145 gene SCO1678, which encodes a GntR-like regulator of the FadR subfamily. Bioinformatic analysis suggested that SCO1678 is part of putative operon (gnt involved in gluconate metabolism. Combining the results of SCO1678 knockout, transcriptional analysis of gnt operon, and Sco1678 protein-DNA electromobility shift assays, we established that Sco1678 protein controls the gluconate operon. It does so via repression of its transcription from a single promoter located between genes SCO1678 and SCO1679. The knockout also influenced, in a medium-dependent manner, the production of secondary metabolites by S. coelicolor. In comparison to the wild type, on gluconate-containing minimal medium, the SCO1678 mutant produced much less actinorhodin and accumulated a yellow-colored pigment, likely to be the cryptic polyketide coelimycin. Possible links between gluconate metabolism and antibiotic production are discussed.

  14. Quantitative proteome and phosphoproteome analyses of Streptomyces coelicolor reveal proteins and phosphoproteins modulating differentiation and secondary metabolism

    DEFF Research Database (Denmark)

    Rioseras, Beatriz; Sliaha, Pavel V; Gorshkov, Vladimir

    2018-01-01

    identified and quantified 3461 proteins corresponding to 44.3% of the S. coelicolor proteome across three developmental stages: vegetative hypha (MI); secondary metabolite producing hyphae (MII); and sporulating hyphae. A total of 1350 proteins exhibited more than 2-fold expression changes during....../Thr/Tyr kinases, making this genus an outstanding model for the study of bacterial protein phosphorylation events. We used mass spectrometry based quantitative proteomics and phosphoproteomics to characterize bacterial differentiation and activation of secondary metabolism of Streptomyces coelicolor. We...... the bacterial differentiation process. These proteins include 136 regulators (transcriptional regulators, transducers, Ser/Thr/Tyr kinases, signalling proteins), as well as 542 putative proteins with no clear homology to known proteins which are likely to play a role in differentiation and secondary metabolism...

  15. In Search of the E. coli Compounds that Change the Antibiotic Production Pattern of Streptomyces coelicolor During Inter-species Interaction.

    Science.gov (United States)

    Mavituna, Ferda; Luti, Khalid Jaber Kadhum; Gu, Lixing

    2016-08-01

    The aim of this work was to investigate the interaction between E.coli and Streptomyces coelicolor A3 (2) for the increased production of undecylprodigiosin and identify the E. coli actives mediating this inter-species interaction. The antibiotics of interest were the red-pigmented undecylprodigiosin and blue-pigmented actinorhodin. Pure cultures of S. coelicolor in a defined medium produced higher concentrations of actinorhodin compared to those of undecylprodigiosin. The latter however, is more important due to its immunosuppressive and antitumor properties. As a strategy to increase undecylprodigiosin production, we added separately, live cells and heat-killed cells of E. coli C600, and the cell-free supernatant of E. coli culture to S. coelicolor cultures in shake flasks. The interaction with live cells of E. coli altered the antibiotic production pattern and undecylprodigiosin production was enhanced by 3.5-fold compared to the pure cultures of S. coelicolor and actinorhodin decreased by 15-fold. The heat-killed cells of E. coli however, had no effect on antibiotic production. In all cases, growth and glucose consumption of S. coelicolor remained almost the same as those observed in the pure culture indicating that the changes in antibiotic production were not due to nutritional stress. Results with cell-free supernatant of E. coli culture indicated that the interaction between S. coelicolor and E. coli was mediated via diffusible molecule(s). Using a set of extraction procedures and agar-well diffusion bioassays, we isolated and preliminarily identified a class of compounds. For the preliminary verification, we added the compound which was the common chemical structural moiety in this class of compounds to the pure S. coelicolor cultures. We observed similar effects on antibiotic production as with the live E. coli cells and their supernatant indicating that this class of compounds secreted by E. coli indeed could act as actives during interspecies

  16. Microwave Assisted Rapid and Green Synthesis of Silver Nanoparticles Using a Pigment Produced by Streptomyces coelicolor klmp33

    OpenAIRE

    Manikprabhu, Deene; Lingappa, K.

    2013-01-01

    Traditional synthesis of silver nanoparticles using chemical methods produces toxic substances. In contrast biological synthesis is regarded as a safe and nontoxic process but the major drawback of biological synthesis is, this process is slow. In the present investigation, we developed a rapid and green synthesis of silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33 in just 90?s. The silver nanoparticles were characterized by UV-visible spectroscopy, transmis...

  17. Streptomyces coelicolor encodes a urate-responsive transcriptional regulator with homology to PecS from plant pathogens.

    Science.gov (United States)

    Huang, Hao; Mackel, Brian J; Grove, Anne

    2013-11-01

    Many transcriptional regulators control gene activity by responding to specific ligands. Members of the multiple-antibiotic resistance regulator (MarR) family of transcriptional regulators feature prominently in this regard, and they frequently function as repressors in the absence of their cognate ligands. Plant pathogens such as Dickeya dadantii encode a MarR homolog named PecS that controls expression of a gene encoding the efflux pump PecM in addition to other virulence genes. We report here that the soil bacterium Streptomyces coelicolor also encodes a PecS homolog (SCO2647) that regulates a pecM gene (SCO2646). S. coelicolor PecS, which exists as a homodimer, binds the intergenic region between pecS and pecM genes with high affinity. Several potential PecS binding sites were found in this intergenic region. The binding of PecS to its target DNA can be efficiently attenuated by the ligand urate, which also quenches the intrinsic fluorescence of PecS, indicating a direct interaction between urate and PecS. In vivo measurement of gene expression showed that activity of pecS and pecM genes is significantly elevated after exposure of S. coelicolor cultures to urate. These results indicate that S. coelicolor PecS responds to the ligand urate by attenuated DNA binding in vitro and upregulation of gene activity in vivo. Since production of urate is associated with generation of reactive oxygen species by xanthine dehydrogenase, we propose that PecS functions under conditions of oxidative stress.

  18. The structure of the small laccase from Streptomyces coelicolor reveals a link between laccases and nitrite reductases

    Czech Academy of Sciences Publication Activity Database

    Skálová, Tereza; Dohnálek, Jan; Ostergaard, L. H.; Ostergaard, P. R.; Kolenko, Petr; Dušková, Jarmila; Štěpánková, Andrea; Hašek, Jindřich

    2009-01-01

    Roč. 385, č. 4 (2009), s. 1165-1178 ISSN 0022-2836 R&D Projects: GA MŠk 1K05008; GA ČR GA305/07/1073; GA AV ČR 1ET400500402 Institutional research plan: CEZ:AV0Z40500505 Keywords : laccase * oxidoreductase * multicopper blue protein * Streptomyces coelicolor * crystal structure Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.871, year: 2009

  19. Characterization of an Lrp/AsnC family regulator SCO3361, controlling actinorhodin production and morphological development in Streptomyces coelicolor.

    Science.gov (United States)

    Liu, Jing; Li, Jie; Dong, Hong; Chen, Yunfu; Wang, Yansheng; Wu, Hang; Li, Changrun; Weaver, David T; Zhang, Lixin; Zhang, Buchang

    2017-07-01

    Lrp/AsnC family regulators have been found in many bacteria as crucial regulators controlling diverse cellular processes. By genomic alignment, we found that SCO3361, an Lrp/AsnC family protein from Streptomyces coelicolor, shared the highest similarity to the SACE_Lrp from Saccharopolyspora erythraea. Deletion of SCO3361 led to dramatic reduction in actinorhodin (Act) production and delay in aerial mycelium formation and sporulation on solid media. Dissection of the mechanism underlying the function of SCO3361 in Act production revealed that it altered the transcription of the cluster-situated regulator gene actII-ORF4 by directly binding to its promoter. SCO3361 was an auto-regulator and simultaneously activated the transcription of its adjacent divergently transcribed gene SCO3362. SCO3361 affected aerial hyphae formation and sporulation of S. coelicolor by activating the expression of amfC, whiB, and ssgB. Phenylalanine and cysteine were identified as the effector molecules of SCO3361, with phenylalanine reducing the binding affinity, whereas cysteine increasing it. Moreover, interactional regulation between SCO3361 and SACE_Lrp was discovered for binding to each other's target gene promoter in this work. Our findings indicate that SCO3361 functions as a pleiotropic regulator controlling secondary metabolism and morphological development in S. coelicolor.

  20. Identification of FadAB Complexes Involved in Fatty Acid β-Oxidation in Streptomyces coelicolor and Construction of a Triacylglycerol Overproducing strain

    Directory of Open Access Journals (Sweden)

    Simón Menendez-Bravo

    2017-08-01

    Full Text Available Oleaginous microorganisms represent possible platforms for the sustainable production of oleochemicals and biofuels due to their metabolic robustness and the possibility to be engineered. Streptomyces coelicolor is among the narrow group of prokaryotes capable of accumulating triacylglycerol (TAG as carbon and energy reserve. Although the pathways for TAG biosynthesis in this organism have been widely addressed, the set of genes required for their breakdown have remained elusive so far. Here, we identified and characterized three gene clusters involved in the β-oxidation of fatty acids (FA. The role of each of the three different S. coelicolor FadAB proteins in FA catabolism was confirmed by complementation of an Escherichia coliΔfadBA mutant strain deficient in β-oxidation. In S. coelicolor, the expression profile of the three gene clusters showed variation related with the stage of growth and the presence of FA in media. Flux balance analyses using a corrected version of the current S. coelicolor metabolic model containing detailed TAG biosynthesis reactions suggested the relevance of the identified fadAB genes in the accumulation of TAG. Thus, through the construction and analysis of fadAB knockout mutant strains, we obtained an S. coelicolor mutant that showed a 4.3-fold increase in the TAG content compared to the wild type strain grown under the same culture conditions.

  1. Enhanced cellulase production by Trichoderma harzianum by cultivation on glycerol followed by induction on cellulosic substrates.

    Science.gov (United States)

    Delabona, Priscila da Silva; Lima, Deise Juliana; Robl, Diogo; Rabelo, Sarita Cândida; Farinas, Cristiane Sanchez; Pradella, José Geraldo da Cruz

    2016-05-01

    The use of glycerol obtained as an intermediate of the biodiesel manufacturing process as carbon source for microbial growth is a potential alternative strategy for the production of enzymes and other high-value bioproducts. This work evaluates the production of cellulase enzymes using glycerol for high cell density growth of Trichoderma harzianum followed by induction with a cellulosic material. Firstly, the influence of the carbon source used in the pre-culture step was investigated in terms of total protein secretion and fungal morphology. Enzymatic productivity was then determined for cultivation strategies using different types and concentrations of carbon source, as well as different feeding procedures (batch and fed-batch). The best strategy for cellulase production was then further studied on a larger scale using a stirred tank bioreactor. The proposed strategy for cellulase production, using glycerol to achieve high cell density growth followed by induction with pretreated sugarcane bagasse, achieved enzymatic activities up to 2.27 ± 0.37 FPU/mL, 106.40 ± 8.87 IU/mL, and 9.04 ± 0.39 IU/mL of cellulase, xylanase, and β-glucosidase, respectively. These values were 2 times higher when compared to the control experiments using glucose instead of glycerol. This novel strategy proved to be a promising approach for improving cellulolytic enzymes production, and could potentially contribute to adding value to biomass within the biofuels sector.

  2. Evidence for the negative regulation of phytase gene expression in Streptomyces lividans and Streptomyces coelicolor.

    Science.gov (United States)

    Boukhris, Ines; Dulermo, Thierry; Chouayekh, Hichem; Virolle, Marie-Joëlle

    2016-01-01

    Sco7697, a gene encoding a phytase, enzyme able to degrade phytate (myo-inositol 1,2,3,4,5,6-hexakis phosphate), the most abundant phosphorus storing compound in plants is present in the genome of S. coelicolor, a soil born bacteria with a saprophytic lifestyle. The expression of this gene was previously shown to be induced in conditions of Pi limitation by the response regulator PhoP binding to an operator sequence, the PHO box, located upstream of the -35 promoter sequence. A close examination of the promoter region of sco7697 revealed the presence of another putative operator site, a Direct Repeat (DR), located downstream of the -10 promoter sequence. In order to determine whether this DR played a role in regulation of sco7697 expression, different variants of the phytase gene promoter region were transcriptionally fused to the ß-glucuronidase reporter gene (GUS). As expected, deletion of the PHO box led to abolition of sco7697 induction in conditions of Pi limitation. Interestingly, alteration of the DR correlated with a dramatic increase of GUS expression but only when PhoP was present. These results demonstrated that this DR is the site of strong negative regulation by an unknown repressor. The latter would impede the necessary activation of phytase expression by PhoP. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Quantitative proteomic analysis of Streptomyces coelicolor development demonstrates that onset of secondary metabolism coincides with hyphae differentiation

    DEFF Research Database (Denmark)

    Manteca, Angel; Sanchez, Jesus; Jung, Hye Ryung

    2010-01-01

    mycelial stages: an early compartmentalized vegetative mycelium (first mycelium, MI), and a multinucleated reproductive mycelium (second mycelium, MII), arising after PCD processes. In the present study, we made a detailed proteomic analysis of the distinct developmental stages of solid confluent...... Streptomyces coelicolor cultures using iTRAQ labelling and LC-MS/MS. A new experimental approach was developed to obtain homogeneous samples at each developmental stage (temporal protein analysis) and also to obtain membrane and cytosolic protein fractions (spatial protein analysis). A total of 345 proteins...

  4. Deletion of a regulatory gene within the cpk gene cluster reveals novel antibacterial activity in Streptomyces coelicolor A3(2)

    NARCIS (Netherlands)

    Gottelt, Marco; Kol, Stefan; Gomez-Escribano, Juan Pablo; Bibb, Mervyn; Takano, Eriko

    Genome sequencing of Streptomyces coelicolor A3(2) revealed an uncharacterized type I polyketide synthase gene cluster (cpk) Here we describe the discovery of a novel antibacterial activity (abCPK) and a yellow-pigmented secondary metabolite (yCPK) after deleting a presumed pathway-specific

  5. Protein Synthesis Elongation Factor Tu Present in Spores of Streptomyces coelicolor Can Be Phosphorylated in Vitro by the Spore Protein Kinase

    Czech Academy of Sciences Publication Activity Database

    Holub, Martin; Bezoušková, Silvia; Kalachová, Ladislava; Weiser, Jaroslav

    2007-01-01

    Roč. 52, č. 5 (2007), s. 471-478 ISSN 0015-5632 R&D Projects: GA ČR GA204/03/1014; GA AV ČR IAA600200702 Institutional research plan: CEZ:AV0Z50200510 Keywords : phosphorylation * s. coelicolor * protein kinase Subject RIV: EE - Microbiology, Virology Impact factor: 0.989, year: 2007

  6. Two novel homologous proteins of Streptomyces coelicolor and Streptomyces lividans are involved in the formation of the rodlet layer and mediate attachment to a hydrophobic surface

    NARCIS (Netherlands)

    Claessen, Dennis; Wösten, Han A.B.; Keulen, Geertje van; Faber, Onno G.; Alves, Alexandra M.C.R.; Meijer, Wim G.; Dijkhuizen, Lubbert

    The filamentous bacteria Streptomyces coelicolor and Streptomyces lividans exhibit a complex life cycle. After a branched submerged mycelium has been established, aerial hyphae are formed that may septate to form chains of spores. The aerial structures possess several surface layers of unknown

  7. Export of functional Streptomyces coelicolor alditol oxidase to the periplasm or cell surface of Escherichia coli and its application in whole-cell biocatalysis

    NARCIS (Netherlands)

    van Bloois, Edwin; Winter, Remko T.; Janssen, Dick B.; Fraaije, Marco W.

    Streptomyces coelicolor A3(2) alditol oxidase (AldO) is a soluble monomeric flavoprotein in which the flavin cofactor is covalently linked to the polypeptide chain. AldO displays high reactivity towards different polyols such as xylitol and sorbitol. These characteristics make AldO industrially

  8. Crystallization and preliminary X-ray analysis of AbsC, a novel regulator of antibiotic production in Streptomyces coelicolor

    International Nuclear Information System (INIS)

    Stevenson, Clare E. M.; Kock, Holger; Mootien, Saraspadee; Davies, Sîan C.; Bibb, Mervyn J.; Lawson, David M.

    2007-01-01

    A novel regulator of antibiotic production in S. coelicolor, AbsC, has been crystallized in space group P2 1 2 1 2 1 . X-ray data to 2.25 Å resolution were collected on station PX 14.1 at Daresbury. Crystals of recombinant AbsC (subunit MW = 18 313 Da; 158 amino acids), a novel regulator of antibiotic production from Streptomyces coelicolor, were grown by vapour diffusion. The protein crystallizes in space group P2 1 2 1 2 1 , with unit-cell parameters a = 43.53, b = 121.30, c = 143.75 Å. Native data to a resolution of 2.25 Å were recorded at station PX 14.1 (Daresbury) from a single crystal. Preliminary analysis of these data suggests that the asymmetric unit contains four copies of the AbsC monomer, giving an estimated solvent content of 47.0%. AbsC belongs to the MarR family of proteins that mediate ligand-responsive transcriptional control

  9. ArgR of Streptomyces coelicolor Is a Pleiotropic Transcriptional Regulator: Effect on the Transcriptome, Antibiotic Production, and Differentiation in Liquid Cultures

    Science.gov (United States)

    Botas, Alma; Pérez-Redondo, Rosario; Rodríguez-García, Antonio; Álvarez-Álvarez, Rubén; Yagüe, Paula; Manteca, Angel; Liras, Paloma

    2018-01-01

    ArgR is a well-characterized transcriptional repressor controlling the expression of arginine and pyrimidine biosynthetic genes in bacteria. In this work, the biological role of Streptomyces coelicolor ArgR was analyzed by comparing the transcriptomes of S. coelicolor ΔargR and its parental strain, S. coelicolor M145, at five different times over a 66-h period. The effect of S. coelicolor ArgR was more widespread than that of the orthologous protein of Escherichia coli, affecting the expression of 1544 genes along the microarray time series. This S. coelicolor regulator repressed the expression of arginine and pyrimidine biosynthetic genes, but it also modulated the expression of genes not previously described to be regulated by ArgR: genes involved in nitrogen metabolism and nitrate utilization; the act, red, and cpk genes for antibiotic production; genes for the synthesis of the osmotic stress protector ectoine; genes related to hydrophobic cover formation and sporulation (chaplins, rodlins, ramR, and whi genes); all the cwg genes encoding proteins for glycan cell wall biosynthesis; and genes involved in gas vesicle formation. Many of these genes contain ARG boxes for ArgR binding. ArgR binding to seven new ARG boxes, located upstream or near the ectA-ectB, afsS, afsR, glnR, and redH genes, was tested by DNA band-shift assays. These data and those of previously assayed fragments permitted the construction of an improved model of the ArgR binding site. Interestingly, the overexpression of sporulation genes observed in the ΔargR mutant in our culture conditions correlated with a sporulation-like process, an uncommon phenotype. PMID:29545785

  10. Enzyme controlled glucose auto-delivery for high cell density cultivations in microplates and shake flasks

    Directory of Open Access Journals (Sweden)

    Casteleijn Marco G

    2008-11-01

    Full Text Available Abstract Background Here we describe a novel cultivation method, called EnBase™, or enzyme-based-substrate-delivery, for the growth of microorganisms in millilitre and sub-millilitre scale which yields 5 to 20 times higher cell densities compared to standard methods. The novel method can be directly applied in microwell plates and shake flasks without any requirements for additional sensors or liquid supply systems. EnBase is therefore readily applicable for many high throughput applications, such as DNA production for genome sequencing, optimisation of protein expression, production of proteins for structural genomics, bioprocess development, and screening of enzyme and metagenomic libraries. Results High cell densities with EnBase are obtained by applying the concept of glucose-limited fed-batch cultivation which is commonly used in industrial processes. The major difference of the novel method is that no external glucose feed is required, but glucose is released into the growth medium by enzymatic degradation of starch. To cope with the high levels of starch necessary for high cell density cultivation, starch is supplied to the growing culture suspension by continuous diffusion from a storage gel. Our results show that the controlled enzyme-based supply of glucose allows a glucose-limited growth to high cell densities of OD600 = 20 to 30 (corresponding to 6 to 9 g l-1 cell dry weight without the external feed of additional compounds in shake flasks and 96-well plates. The final cell density can be further increased by addition of extra nitrogen during the cultivation. Production of a heterologous triosphosphate isomerase in E. coli BL21(DE3 resulted in 10 times higher volumetric product yield and a higher ratio of soluble to insoluble product when compared to the conventional production method. Conclusion The novel EnBase method is robust and simple-to-apply for high cell density cultivation in shake flasks and microwell plates. The

  11. Disruption of the GDP-mannose synthesis pathway in Streptomyces coelicolor results in antibiotic hyper-susceptible phenotypes.

    Science.gov (United States)

    Howlett, Robert; Anttonen, Katri; Read, Nicholas; Smith, Margaret C M

    2018-04-01

    Actinomycete bacteria use polyprenol phosphate mannose as a lipid linked sugar donor for extra-cytoplasmic glycosyl transferases that transfer mannose to cell envelope polymers, including glycoproteins and glycolipids. We showed recently that strains of Streptomyces coelicolor with mutations in the gene ppm1 encoding polyprenol phosphate mannose synthase were both resistant to phage φC31 and have greatly increased susceptibility to antibiotics that mostly act on cell wall biogenesis. Here we show that mutations in the genes encoding enzymes that act upstream of Ppm1 in the polyprenol phosphate mannose synthesis pathway can also confer phage resistance and antibiotic hyper-susceptibility. GDP-mannose is a substrate for Ppm1 and is synthesised by GDP-mannose pyrophosphorylase (GMP; ManC) which uses GTP and mannose-1-phosphate as substrates. Phosphomannomutase (PMM; ManB) converts mannose-6-phosphate to mannose-1-phosphate. S. coelicolor strains with knocked down GMP activity or with a mutation in sco3028 encoding PMM acquire phenotypes that resemble those of the ppm1 - mutants i.e. φC31 resistant and susceptible to antibiotics. Differences in the phenotypes of the strains were observed, however. While the ppm1 - strains have a small colony phenotype, the sco3028 :: Tn5062 mutants had an extremely small colony phenotype indicative of an even greater growth defect. Moreover we were unable to generate a strain in which GMP activity encoded by sco3039 and sco4238 is completely knocked out, indicating that GMP is also an important enzyme for growth. Possibly GDP-mannose is at a metabolic branch point that supplies alternative nucleotide sugar donors.

  12. Improved Prediction of Phosphorus Dynamics in Biotechnological Processes by Considering Precipitation and Polyphosphate Formation: A Case Study on Antibiotic Production with Streptomyces coelicolor

    DEFF Research Database (Denmark)

    Bürger, Patrick; Flores-Alsina, Xavier; Arellano-Garcia, Harvey

    2018-01-01

    The multiplicity of physicochemical and biological processes, where phosphorus is involved, makes their accurate prediction using current mathematical models in biotechnology quite a challenge. In this work, an antibiotic production model of Streptomyces coelicolor is chosen as a representative...... approach describing intracellular polyphosphate accumulation and consumption has been developed and implemented. A heuristic re-estimation of selected parameters is carried out to improve overall model performance. The improved process model predicts phosphate dynamics (root mean squared error ≤52h: −90...

  13. Isolation and Cultivation of Anaerobes

    DEFF Research Database (Denmark)

    Aragao Börner, Rosa

    2016-01-01

    Anaerobic microorganisms play important roles in different biotechnological processes. Their complex metabolism and special cultivation requirements have led to less isolated representatives in comparison to their aerobic counterparts.In view of that, the isolation and cultivation of anaerobic...

  14. [Dendrobium officinale stereoscopic cultivation method].

    Science.gov (United States)

    Si, Jin-Ping; Dong, Hong-Xiu; Liao, Xin-Yan; Zhu, Yu-Qiu; Li, Hui

    2014-12-01

    The study is aimed to make the most of available space of Dendrobium officinale cultivation facility, reveal the yield and functional components variation of stereoscopic cultivated D. officinale, and improve quality, yield and efficiency. The agronomic traits and yield variation of stereoscopic cultivated D. officinale were studied by operating field experiment. The content of polysaccharide and extractum were determined by using phenol-sulfuric acid method and 2010 edition of "Chinese Pharmacopoeia" Appendix X A. The results showed that the land utilization of stereoscopic cultivated D. officinale increased 2.74 times, the stems, leaves and their total fresh or dry weight in unit area of stereoscopic cultivated D. officinale were all heavier than those of the ground cultivated ones. There was no significant difference in polysaccharide content between stereoscopic cultivation and ground cultivation. But the extractum content and total content of polysaccharide and extractum were significantly higher than those of the ground cultivated ones. In additional, the polysaccharide content and total content of polysaccharide and extractum from the top two levels of stereoscopic culture matrix were significantly higher than that of the ones from the other levels and ground cultivation. Steroscopic cultivation can effectively improves the utilization of space and yield, while the total content of polysaccharides and extractum were significantly higher than that of the ground cultivated ones. The significant difference in Dendrobium polysaccharides among the plants from different height of stereo- scopic culture matrix may be associated with light factor.

  15. Bioprocess intensification of antibiotic production by Streptomyces coelicolor A3(2) in micro-porous culture

    Energy Technology Data Exchange (ETDEWEB)

    Ndlovu, T.M., E-mail: tm.ndlovu@nutriss.com [NUTRISS Limited, INEX, Herschel Annex, Kings Road, Newcastle upon Tyne NE1 7RU (United Kingdom); Ward, A.C. [School of Biology, Newcastle University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Department of Microbiology, Chung-Ang University, College of Medicine, Seoul, Republic of Korea 156-756 (Korea, Republic of); Glassey, J. [School of Chemical Engineering and Advanced Materials, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom); Eskildsen, J. [NUTRISS Limited, INEX, Herschel Annex, Kings Road, Newcastle upon Tyne NE1 7RU (United Kingdom); Akay, G. [School of Chemical Engineering and Advanced Materials, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2015-04-01

    A novel functionalized micro-porous matrix was developed with well-controlled physicochemical proprieties such as pore size and surface chemistry. The matrix was used as a solid support in the growth of “Streptomyces coelicolor” A3(2) to enhance the production of antibiotics. The results shown support a higher production of prodigiosin and actinorhodin with overall production increase of 2–5 and 6–17, respectively, compared to conventional submerged liquid culture, offering a potential improvement in volumetric productivity. Scanning Electron Microscopy was used to evaluate pore size as well as bacterial adhesion, penetration, proliferation and migration within the micro-porous matrix. - Highlights: • Preparation of novel micro-porous matrix with different physiochemical proprieties • S. coelicolor A3(2) was cultured in those micro-porous and antibiotics was enhanced. • Matrix pore sizes and surface chemistry influenced bacterial signalling. • Bacterial signalling has a profound effect in the overproduction of Prodigiosin and actinorhodin. • Prodigiosin and actinorhodin production within micro-porous was 5–17 times higher compared with liquid growth.

  16. Whey protein isolate with improved film properties through cross-linking catalyzed by small laccase from Streptomyces coelicolor.

    Science.gov (United States)

    Quan, Wei; Zhang, Chong; Zheng, Meixia; Lu, Zhaoxin; Lu, Fengxia

    2018-08-01

    The effects of small laccase (SLAC) from Streptomyces coelicolor on the properties of whey protein isolate (WPI) films were studied. WPI was catalyze by SLAC without phenolic acid assistance. Particle size distribution results showed that some complexes with higher relative molecular weight formed in WPI samples treated with SLAC. The content of α-helixes decreased while those of β-sheets and random coils increased following SLAC treatment according to circular dichroism results. Fourier transform infrared spectral analysis suggested that some conformational changes occurred in WPI following SLAC treatment. Analysis of WPI films prepared by casting after SLAC treatment indicated that their film properties were all improved, including mechanical properties, solubility, water vapor, oxygen and carbon dioxide barrier properties, film color, light transmission, transparency and thermal properties. Compared with that of the control film, some obvious differences in the morphology of the WPI films were observed following SLAC treatment. This report demonstrates that laccase can directly catalyze protein cross-linking, which may be useful to improve the performance of protein films. In this study, SLAC was applied to WPI edible film during the film-making process. The results showed that SLAC can catalyze WPI cross-linking without phenolic acid assistance, and WPI film properties were improved after SLAC treatment. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  17. Molecular characterization of Streptomyces coelicolor A(3) SCO6548 as a cellulose 1,4-β-cellobiosidase.

    Science.gov (United States)

    Lim, Ju-Hyeon; Lee, Chang-Ro; Dhakshnamoorthy, Vijayalakshmi; Park, Jae Seon; Hong, Soon-Kwang

    2016-02-01

    Genomic sequencing analysis and previous studies have shown that there are eight genes in Streptomyces coelicolor A3(2) encoding putative cellulases. One of these genes, sco6548, was cloned into the Streptomyces/Escherichia coli shuttle vector pUWL201PW. The recombinant protein was successfully overexpressed in S. lividans TK24 under the control of the strong ermE promoter. Sco6548 was 1740 bp in length, and encoded a 579-amino acid-, 60.8-kDa protein with strong hydrolyzing activity toward Avicel and filter paper, yielding cellobiose as the final product. SCO6548 showed optimal activity at 50°C and pH 5. The Km values of SCO6548 toward Avicel and filter paper were 15.38 and 16.1 mg/mL, respectively. The Vmax values toward Avicel and filter paper were 0.432 and 0.084 μM/min, respectively. EDTA did not affect cellulase activity; however, several divalent cations, including Co(2+), Cu(2+), Ni(2+) and Mn(2+) (at 10 mM) had severe inhibitory effects on enzyme activity. Our analysis showed that SCO6548 is a cellulose 1,4-β-cellobiosidase that hydrolyzes cellulose into cellobiose. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Bioprocess intensification of antibiotic production by Streptomyces coelicolor A3(2) in micro-porous culture

    International Nuclear Information System (INIS)

    Ndlovu, T.M.; Ward, A.C.; Glassey, J.; Eskildsen, J.; Akay, G.

    2015-01-01

    A novel functionalized micro-porous matrix was developed with well-controlled physicochemical proprieties such as pore size and surface chemistry. The matrix was used as a solid support in the growth of “Streptomyces coelicolor” A3(2) to enhance the production of antibiotics. The results shown support a higher production of prodigiosin and actinorhodin with overall production increase of 2–5 and 6–17, respectively, compared to conventional submerged liquid culture, offering a potential improvement in volumetric productivity. Scanning Electron Microscopy was used to evaluate pore size as well as bacterial adhesion, penetration, proliferation and migration within the micro-porous matrix. - Highlights: • Preparation of novel micro-porous matrix with different physiochemical proprieties • S. coelicolor A3(2) was cultured in those micro-porous and antibiotics was enhanced. • Matrix pore sizes and surface chemistry influenced bacterial signalling. • Bacterial signalling has a profound effect in the overproduction of Prodigiosin and actinorhodin. • Prodigiosin and actinorhodin production within micro-porous was 5–17 times higher compared with liquid growth

  19. Cultivating an entrepreneurial mindset.

    Science.gov (United States)

    Matheson, Sandra A

    2013-01-01

    Now as never before, familiar challenges require bold, novel approaches. Registered dietitians will benefit by cultivating an entrepreneurial mindset that involves being comfortable with uncertainty, learning to take calculated risks, and daring to just try it. An entrepreneur is someone who takes risks to create something new, usually in business. But the entrepreneurial mindset is available to anyone prepared to rely only on their own abilities for their economic security and expect no opportunity without first creating value for others.

  20. Cultivating strategic thinking skills.

    Science.gov (United States)

    Shirey, Maria R

    2012-06-01

    This department highlights change management strategies that may be successful in strategically planning and executing organizational change initiatives. With the goal of presenting practical approaches helpful to nurse leaders advancing organizational change, content includes evidence-based projects, tools, and resources that mobilize and sustain organizational change initiatives. In this article, the author presents an overview of strategic leadership and offers approaches for cultivating strategic thinking skills.

  1. Ligand-bound Structures and Site-directed Mutagenesis Identify the Acceptor and Secondary Binding Sites of Streptomyces coelicolor Maltosyltransferase GlgE*

    Science.gov (United States)

    Syson, Karl; Stevenson, Clare E. M.; Miah, Farzana; Barclay, J. Elaine; Tang, Minhong; Gorelik, Andrii; Rashid, Abdul M.; Lawson, David M.; Bornemann, Stephen

    2016-01-01

    GlgE is a maltosyltransferase involved in α-glucan biosynthesis in bacteria that has been genetically validated as a target for tuberculosis therapies. Crystals of the Mycobacterium tuberculosis enzyme diffract at low resolution so most structural studies have been with the very similar Streptomyces coelicolor GlgE isoform 1. Although the donor binding site for α-maltose 1-phosphate had been previously structurally defined, the acceptor site had not. Using mutagenesis, kinetics, and protein crystallography of the S. coelicolor enzyme, we have now identified the +1 to +6 subsites of the acceptor/product, which overlap with the known cyclodextrin binding site. The sugar residues in the acceptor subsites +1 to +5 are oriented such that they disfavor the binding of malto-oligosaccharides that bear branches at their 6-positions, consistent with the known acceptor chain specificity of GlgE. A secondary binding site remote from the catalytic center was identified that is distinct from one reported for the M. tuberculosis enzyme. This new site is capable of binding a branched α-glucan and is most likely involved in guiding acceptors toward the donor site because its disruption kinetically compromises the ability of GlgE to extend polymeric substrates. However, disruption of this site, which is conserved in the Streptomyces venezuelae GlgE enzyme, did not affect the growth of S. venezuelae or the structure of the polymeric product. The acceptor subsites +1 to +4 in the S. coelicolor enzyme are well conserved in the M. tuberculosis enzyme so their identification could help inform the design of inhibitors with therapeutic potential. PMID:27531751

  2. A novel compartment, the 'subqpical stem' of the aerial hyphae, is the location of a sigN-dependent, developmentally distinct transcription in Streptomyces coelicolor.

    OpenAIRE

    Dalton, KA; Thibessard, A; Hunter, JI; Kelemen, GH

    2007-01-01

    Streptomyces coelicolor has nine SigB-like RNA polymerase sigma factors, several of them implicated in morphological differentiation and/or responses to different stresses. One of the nine, SigN, is the focus of this article. A constructed sigN null mutant was delayed in development and exhibited a bald phenotype when grown on minimal medium containing glucose as carbon source. One of two distinct sigN promoters, sigNP1, was active only during growth on solid medium, when its activation coinc...

  3. Transition in nori cultivation

    DEFF Research Database (Denmark)

    Delaney, Alyne

    2011-01-01

    . Technological change has had a profound impact on both the manner of nori production as well as the household division of labor and work and gender roles. Women play a key role in nori production today. With better understanding of such outward manifestations of culture and society we can bring the human...... of social and environmental sustainability, we must understand both society and cultural institutions. With this in mind, this article focuses on the division of labor among cultivators, particularly along gender lines and the impacts, on a cultural level, of technological change on nori production...

  4. Convergent Transcription in the Butyrolactone Regulon in Streptomyces coelicolor Confers a Bistable Genetic Switch for Antibiotic Biosynthesis

    Science.gov (United States)

    Chatterjee, Anushree; Drews, Laurie; Mehra, Sarika; Takano, Eriko; Kaznessis, Yiannis N.; Hu, Wei-Shou

    2011-01-01

    cis-encoded antisense RNAs (cis asRNA) have been reported to participate in gene expression regulation in both eukaryotic and prokaryotic organisms. Its presence in Streptomyces coelicolor has also been reported recently; however, its role has yet to be fully investigated. Using mathematical modeling we explore the role of cis asRNA produced as a result of convergent transcription in scbA-scbR genetic switch. scbA and scbR gene pair, encoding repressor–amplifier proteins respectively, mediates the synthesis of a signaling molecule, the γ-butyrolactone SCB1 and controls the onset of antibiotic production. Our model considers that transcriptional interference caused by convergent transcription of two opposing RNA polymerases results in fatal collision and transcriptional termination, which suppresses transcription efficiency. Additionally, convergent transcription causes sense and antisense interactions between complementary sequences from opposing strands, rendering the full length transcript inaccessible for translation. We evaluated the role of transcriptional interference and the antisense effect conferred by convergent transcription on the behavior of scbA-scbR system. Stability analysis showed that while transcriptional interference affects the system, it is asRNA that confers scbA-scbR system the characteristics of a bistable switch in response to the signaling molecule SCB1. With its critical role of regulating the onset of antibiotic synthesis the bistable behavior offers this two gene system the needed robustness to be a genetic switch. The convergent two gene system with potential of transcriptional interference is a frequent feature in various genomes. The possibility of asRNA regulation in other such gene-pairs is yet to be examined. PMID:21765930

  5. redD and actII-ORF4, Pathway-Specific Regulatory Genes for Antibiotic Production in Streptomyces coelicolor A3(2), Are Transcribed In Vitro by an RNA Polymerase Holoenzyme Containing σhrdD

    NARCIS (Netherlands)

    Fujii, T.; Gramajo, H.C.; Takano, E.; Bibb, M.J.

    1996-01-01

    redD and actII-ORF4, regulatory genes required for synthesis of the antibiotics undecylprodigiosin and actinorhodin by Streptomyces coelicolor A3(2), were transcribed in vitro by an RNA polymerase holoenzyme containing σhrdD. Disruption of hrdD had no effect on antibiotic production, indicating that

  6. Sporulation-specific cell division defects in ylmE mutants of Streptomyces coelicolor are rescued by additional deletion of ylmD.

    Science.gov (United States)

    Zhang, Le; Willemse, Joost; Hoskisson, Paul A; van Wezel, Gilles P

    2018-05-09

    Cell division during the reproductive phase of the Streptomyces life-cycle requires tight coordination between synchronous formation of multiple septa and DNA segregation. One remarkable difference with most other bacterial systems is that cell division in Streptomyces is positively controlled by the recruitment of FtsZ by SsgB. Here we show that deletion of ylmD (SCO2081) or ylmE (SCO2080), which lie in operon with ftsZ in the dcw cluster of actinomycetes, has major consequences for sporulation-specific cell division in Streptomyces coelicolor. Electron and fluorescence microscopy demonstrated that ylmE mutants have a highly aberrant phenotype with defective septum synthesis, and produce very few spores with low viability and high heat sensitivity. FtsZ-ring formation was also highly disturbed in ylmE mutants. Deletion of ylmD had a far less severe effect on sporulation. Interestingly, the additional deletion of ylmD restored sporulation to the ylmE null mutant. YlmD and YlmE are not part of the divisome, but instead localize diffusely in aerial hyphae, with differential intensity throughout the sporogenic part of the hyphae. Taken together, our work reveals a function for YlmD and YlmE in the control of sporulation-specific cell division in S. coelicolor, whereby the presence of YlmD alone results in major developmental defects.

  7. Metabolic switches and adaptations deduced from the proteomes of Streptomyces coelicolor wild type and phoP mutant grown in batch culture.

    Science.gov (United States)

    Thomas, Louise; Hodgson, David A; Wentzel, Alexander; Nieselt, Kay; Ellingsen, Trond E; Moore, Jonathan; Morrissey, Edward R; Legaie, Roxane; Wohlleben, Wolfgang; Rodríguez-García, Antonio; Martín, Juan F; Burroughs, Nigel J; Wellington, Elizabeth M H; Smith, Margaret C M

    2012-02-01

    Bacteria in the genus Streptomyces are soil-dwelling oligotrophs and important producers of secondary metabolites. Previously, we showed that global messenger RNA expression was subject to a series of metabolic and regulatory switches during the lifetime of a fermentor batch culture of Streptomyces coelicolor M145. Here we analyze the proteome from eight time points from the same fermentor culture and, because phosphate availability is an important regulator of secondary metabolite production, compare this to the proteome of a similar time course from an S. coelicolor mutant, INB201 (ΔphoP), defective in the control of phosphate utilization. The proteomes provide a detailed view of enzymes involved in central carbon and nitrogen metabolism. Trends in protein expression over the time courses were deduced from a protein abundance index, which also revealed the importance of stress pathway proteins in both cultures. As expected, the ΔphoP mutant was deficient in expression of PhoP-dependent genes, and several putatively compensatory metabolic and regulatory pathways for phosphate scavenging were detected. Notably there is a succession of switches that coordinately induce the production of enzymes for five different secondary metabolite biosynthesis pathways over the course of the batch cultures.

  8. Carbon-flux distribution within Streptomyces coelicolor metabolism: a comparison between the actinorhodin-producing strain M145 and its non-producing derivative M1146.

    Directory of Open Access Journals (Sweden)

    Fabien Coze

    Full Text Available Metabolic Flux Analysis is now viewed as essential to elucidate the metabolic pattern of cells and to design appropriate genetic engineering strategies to improve strain performance and production processes. Here, we investigated carbon flux distribution in two Streptomyces coelicolor A3 (2 strains: the wild type M145 and its derivative mutant M1146, in which gene clusters encoding the four main antibiotic biosynthetic pathways were deleted. Metabolic Flux Analysis and (13C-labeling allowed us to reconstruct a flux map under steady-state conditions for both strains. The mutant strain M1146 showed a higher growth rate, a higher flux through the pentose phosphate pathway and a higher flux through the anaplerotic phosphoenolpyruvate carboxylase. In that strain, glucose uptake and the flux through the Krebs cycle were lower than in M145. The enhanced flux through the pentose phosphate pathway in M1146 is thought to generate NADPH enough to face higher needs for biomass biosynthesis and other processes. In both strains, the production of NADPH was higher than NADPH needs, suggesting a key role for nicotinamide nucleotide transhydrogenase for redox homeostasis. ATP production is also likely to exceed metabolic ATP needs, indicating that ATP consumption for maintenance is substantial.Our results further suggest a possible competition between actinorhodin and triacylglycerol biosynthetic pathways for their common precursor, acetyl-CoA. These findings may be instrumental in developing new strategies exploiting S. coelicolor as a platform for the production of bio-based products of industrial interest.

  9. Glass bead cultivation of fungi

    DEFF Research Database (Denmark)

    Droce, Aida; Sørensen, Jens Laurids; Giese, H.

    2013-01-01

    Production of bioactive compounds and enzymes from filamentous fungi is highly dependent on cultivation conditions. Here we present an easy way to cultivate filamentous fungi on glass beads that allow complete control of nutrient supply. Secondary metabolite production in Fusarium graminearum...... and Fusarium solani cultivated on agar plates, in shaking liquid culture or on glass beads was compared. Agar plate culture and glass bead cultivation yielded comparable results while liquid culture had lower production of secondary metabolites. RNA extraction from glass beads and liquid cultures was easier...... to specific nutrient factors. •Fungal growth on glass beads eases and improves fungal RNA extraction....

  10. Starting from grape cultivation.

    Science.gov (United States)

    Yoshida, A

    1992-06-01

    Rapid population growth can only be stopped by lowering the fertility rate. The UNFPA recommends improving the employment opportunities for women as the single best way of achieving this reduction. An example of this phenomenon is the grape cultivation in the Nordeste (Northeastern) region of Brazil. This area is the poorest part of Brazil and has the highest proportion of indigent people. These people have been deforesting the Amazon in search of a better life. What they have done is sterilize the land and turned a tropical rain forest into a desert. In an effort to reverse this trend, grape cultivation has been introduced in an area called Petrolina. The area is very dry with less than 500 mm of precipitation annually. They do have access to a 5000 square kilometer artificial lake (the largest in the world) and the 3rd largest river in Brazil (the Sao Francisco). In an effort to avoid using agricultural medicines, the vines are fertilized with organic matter created on the farm and little or no pesticides are used since pests do not live in such an arid region. It has taken 20 years of trial and error, but the quality of the grapes is now very high and is competitive on the world market. Because of climate and location, harvesting is done year round which increases the productivity of the land. The farm managers have found that married women make the best workers and have the highest level of productivity. Age at 1st marriage averages 24-25, compared with 15-16 for unemployed women in the same area. The fertility rate averages 50% of that for unemployed women in the same area. Agricultural development offers the best opportunity for the women of developing countries. It can pay a high wage, reduce fertility, and replant desert areas.

  11. Micrometeorological principles of protected cultivation

    Science.gov (United States)

    Protected cultivation is a broad term commonly used among producers of specialty crops. Techniques can range from complex fixed structures to field site selection, to straightforward cultural practices in the field. This introduction to the ASHS workshop "Protected cultivation for fruit crops" consi...

  12. Production of ethanol in batch and fed-batch fermentation of soluble sugar

    International Nuclear Information System (INIS)

    Chaudhary, M.Y.; Shah, M.A.; Shah, F.H.

    1991-01-01

    Keeping in view of the demand and need for alternate energy source, especially liquid fuels and the availability of raw materials in Pakistan, we have carried out biochemical and technological studies for ethanol through fermentation of renewable substrates. Molasses and sugar cane have been used as substrate for yeast fermentation. Selected yeast were used in both batch and semi continuous fermentation of molasses. Clarified dilute molasses were fermented with different strains of Saccharomyces cerevisiae. Ethanol concentration after 64 hours batch fermentation reached 9.4% with 90% yield based on sugar content. During feed batch system similar results were obtained after a fermentation cycle of 48 hours resulting in higher productivity. Similarly carbohydrates in fruit juices and hydro lysates of biomass can be economically fermented to ethanol to be used as feed stock for other chemicals. (author)

  13. Optimization of a fed-batch fermentation process for production of ...

    African Journals Online (AJOL)

    African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 10, No 9 (2011) >. Log in or Register to get access to full text downloads.

  14. Tracking control of concentration profiles in a fed-batch bioreactor using a linear algebra methodology.

    Science.gov (United States)

    Rómoli, Santiago; Serrano, Mario Emanuel; Ortiz, Oscar Alberto; Vega, Jorge Rubén; Eduardo Scaglia, Gustavo Juan

    2015-07-01

    Based on a linear algebra approach, this paper aims at developing a novel control law able to track reference profiles that were previously-determined in the literature. A main advantage of the proposed strategy is that the control actions are obtained by solving a system of linear equations. The optimal controller parameters are selected through Monte Carlo Randomized Algorithm in order to minimize a proposed cost index. The controller performance is evaluated through several tests, and compared with other controller reported in the literature. Finally, a Monte Carlo Randomized Algorithm is conducted to assess the performance of the proposed controller. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Biocatalytic hydroxylation of linoleic acid in a double-fed batch system with lipoxygenase and cysteine

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Elshof, M.B.W.; Veldink, G.A.

    1998-01-01

    The enzymatic large-scale preparation of unsaturated fatty acid hydroperoxides is the first step in the preparation of the corresponding fatty acid hydroxides. Since hydroxides are more suitable than hydroperoxides as precursors of fine chemicals like certain flavour compounds, a convenient and

  16. Boosted structured additive regression for Escherichia coli fed-batch fermentation modeling.

    Science.gov (United States)

    Melcher, Michael; Scharl, Theresa; Luchner, Markus; Striedner, Gerald; Leisch, Friedrich

    2017-02-01

    The quality of biopharmaceuticals and patients' safety are of highest priority and there are tremendous efforts to replace empirical production process designs by knowledge-based approaches. Main challenge in this context is that real-time access to process variables related to product quality and quantity is severely limited. To date comprehensive on- and offline monitoring platforms are used to generate process data sets that allow for development of mechanistic and/or data driven models for real-time prediction of these important quantities. Ultimate goal is to implement model based feed-back control loops that facilitate online control of product quality. In this contribution, we explore structured additive regression (STAR) models in combination with boosting as a variable selection tool for modeling the cell dry mass, product concentration, and optical density on the basis of online available process variables and two-dimensional fluorescence spectroscopic data. STAR models are powerful extensions of linear models allowing for inclusion of smooth effects or interactions between predictors. Boosting constructs the final model in a stepwise manner and provides a variable importance measure via predictor selection frequencies. Our results show that the cell dry mass can be modeled with a relative error of about ±3%, the optical density with ±6%, the soluble protein with ±16%, and the insoluble product with an accuracy of ±12%. Biotechnol. Bioeng. 2017;114: 321-334. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. Mechanistic Models for Process Development and Optimization of Fed-batch Fermentation Systems

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Albæk, Mads O.

    2016-01-01

    This work discusses the application of mechanistic models to pilot scale filamentous fungal fermentation systems operated at Novozymes A/S. For on-line applications, a state estimator model is developed based on a stoichiometric balance in order to predict the biomass and product concentration....... This is based on on-line gas measurements and ammonia addition flow rate measurements. Additionally, a mechanistic model is applied offline as a tool for batch planning, based on definition of the process back pressure, aeration rate and stirrer speed. This allows the batch starting fill to be planned, taking...... into account the oxygen transfer conditions, as well as the evaporation rates of the system. Mechanistic models are valuable tools which are applicable for both process development and optimization. The state estimator described will be a valuable tool for future work as part of control strategy development...

  18. A review of control strategies for manipulating the feed rate in fed-batch fermentation processes

    DEFF Research Database (Denmark)

    Mears, Lisa; Stocks, Stuart M.; Sin, Gürkan

    2017-01-01

    . This review covers a range of strategies which have been employed to use the feed rate as a manipulated variable in a control strategy. The feed rate is chosen as the focus for this review, as it is seen that this variable may be used towards many different objectives depending on the process of interest...

  19. Evaluation of biomass production in unleaded gasoline and BTEX-fed batch reactors.

    Science.gov (United States)

    Acuna-Askar, K; Englande, A J; Ramirez-Medrano, A; Coronado-Guardiola, J E; Chavez-Gomez, B

    2003-01-01

    BTEX removal under aerobic conditions by unleaded gasoline acclimated biomass and BTEX acclimated biomass, and the effect of surfactant on BTEX biodegradation were evaluated. The effect of BTEX concentration as the sole source of carbon for biomass acclimation and the effect of yeast extract on cell growth in unleaded gasoline-fed reactors were also evaluated. For the unleaded gasoline acclimated biomass, benzene was shown the most recalcitrant among all BTEX, followed by o-xylene and toluene with 16-23%, 35-41% and 57-69% biodegradation, respectively. Ethylbenzene was consistently the fastest BTEX chemical removed with 99% biodegradation for the four bioreactor acclimated biomasses tested. For the 1,200 ppm BTEX acclimated biomass, benzene showed the highest removal efficiency (99%) among the four biomass environmental conditions tested, along with 99% toluene and 99% ethylbenzene biodegradation. O-xylene showed 92-94% removal. In all bioassays tested Tergitol NP-10 was fully removed, and did not have a substantial effect on BTEX biodegradation at the end of a 10-day evaluation.

  20. Production-process optimization algorithm: Application to fed-batch bioprocess

    Czech Academy of Sciences Publication Activity Database

    Pčolka, M.; Čelikovský, Sergej

    2017-01-01

    Roč. 354, č. 18 (2017), s. 8529-8551 ISSN 0016-0032 R&D Projects: GA ČR(CZ) GA17-04682S Institutional support: RVO:67985556 Keywords : Optimal control * Bioprocess * Optimization Subject RIV: BC - Control Systems Theory OBOR OECD: Automation and control systems Impact factor: 3.139, year: 2016 https://doi.org/10.1016/j.jfranklin.2017.10.012

  1. Degradation of chlorophenol mixtures in a fed-batch system by two ...

    African Journals Online (AJOL)

    2010-12-16

    Dec 16, 2010 ... water is fed to the biological treatment unit either intermittently or ... the same culture in a binary mixture and in ternary mixture of 2,4,6TCP; 2,3,5 .... Solving the balance equation (Eq. (2)) with the initial condi- tions of the ...

  2. Multi-objective optimization of glycopeptide antibiotic production in batch and fed batch processes

    DEFF Research Database (Denmark)

    Maiti, Soumen K.; Eliasson Lantz, Anna; Bhushan, Mani

    2011-01-01

    batch operations using process model for Amycolatopsis balhimycina, a glycopeptide antibiotic producer. This resulted in a set of several pareto optimal solutions with the two objectives ranging from (0.75gl−1, 3.97g$-1) to (0.44gl−1, 5.19g$-1) for batch and from (1.5gl−1, 5.46g$-1) to (1.1gl−1, 6.34g...

  3. Cultivo da levedura Phaffia rhodozyma (Xanthophyllomyces dendrorhous em processo descontínuo alimentado para produção de astaxantina Cultivation of Phaffia rhodozyma (Xanthophyllomyces dendrorhous yeast in discontinuous system to obtain astaxanthin

    Directory of Open Access Journals (Sweden)

    Miriam Blümel Chociai

    2002-12-01

    Full Text Available A levedura Phaffia rhodozyma, produtora de astaxantina, pigmento carotenóide largamente empregado na aqüicultura de peixes e crustáceos, pode ser eficientemente cultivada num meio de cultura de baixo custo, à base de caldo de cana diluído 1:10 e uréia a 1 g/L. No entanto, a produção de biomassa e a formação do carotenóide sofrem a inibição pelo substrato (efeito "Crabtree", limitando desta forma a utilização do caldo de cana com concentrações da fonte de carbono superiores a 20 g/L, importante consideração na produção industrial de astaxantina. No presente trabalho, o cultivo da levedura P. rhodozyma foi realizado em processo descontínuo alimentado, no qual se obteve produtividade volumétrica de 0,024 mg astaxantina/L.h. em relação aos 0,013 mg astaxantina/L.h. obtidos no cultivo controle, que não sofreu alimentação da fonte de carbono.The yeast Phaffia rhodozyma produces astaxanthin, a carotenoid pigment widely applied in fish and crustaceous cultivation. This yeast can be efficiently cultured in a low cost medium, sugar cane broth diluted 1:10 and supplemented with 1 g/L urea. However, the biomass and astaxanthin production undergo inhibition by the substrate (Crabtree effect, limiting the utilization of sugar cane broth up to 20 g/L total sugar concentration. Therefore, this effect must be considered during the industrial production of astaxanthin. In the present work, using fed batch system to cultivate P. rhodozyma we were able to obtain 0.024 mg astaxanthin/l.h compared to 0.013 mg astaxanthin/l.h obtained by the discontinuous cultivation system.

  4. The MreB-like protein Mbl of Streptomyces coelicolor A3(2) depends on MreB for proper localization and contributes to spore wall synthesis.

    Science.gov (United States)

    Heichlinger, Andrea; Ammelburg, Moritz; Kleinschnitz, Eva-Maria; Latus, Annette; Maldener, Iris; Flärdh, Klas; Wohlleben, Wolfgang; Muth, Günther

    2011-04-01

    Most bacteria with a rod-shaped morphology contain an actin-like cytoskeleton consisting of MreB polymers, which form helical spirals underneath the cytoplasmic membrane to direct peptidoglycan synthesis for the elongation of the cell wall. In contrast, MreB of Streptomyces coelicolor is not required for vegetative growth but has a role in sporulation. Besides MreB, S. coelicolor encodes two further MreB-like proteins, Mbl and SCO6166, whose function is unknown. Whereas MreB and Mbl are highly similar, SCO6166 is shorter, lacking the subdomains IB and IIB of actin-like proteins. Here, we showed that MreB and Mbl are not functionally redundant but cooperate in spore wall synthesis. Expression analysis by semiquantitative reverse transcription-PCR revealed distinct expression patterns. mreB and mbl are induced predominantly during morphological differentiation. In contrast, sco6166 is strongly expressed during vegetative growth but switched off during sporulation. All genes could be deleted without affecting viability. Even a ΔmreB Δmbl double mutant was viable. Δsco6166 had a wild-type phenotype. ΔmreB, Δmbl, and ΔmreB Δmbl produced swollen, prematurely germinating spores that were sensitive to various kinds of stress, suggesting a defect in spore wall integrity. During aerial mycelium formation, an Mbl-mCherry fusion protein colocalized with an MreB-enhanced green fluorescent protein (MreB-eGFP) fusion protein at the sporulation septa. Whereas MreB-eGFP localized properly in the Δmbl mutant, Mbl-mCherry localization depended on the presence of a functional MreB protein. Our results revealed that MreB and Mbl cooperate in the synthesis of the thickened spore wall, while SCO6166 has a nonessential function during vegetative growth.

  5. Roles of putative sodium-hydrogen antiporter (SHA) genes in S. coelicolor A3(2) culture with pH variation.

    Science.gov (United States)

    Kim, Yoon Jung; Moon, Myung Hee; Lee, Jae Sun; Hong, Soon-Kwang; Chang, Yong Keun

    2011-09-01

    Culture pH change has some important roles in signal transduction and secondary metabolism. We have already reported that acidic pH shock enhanced actinorhodin production in Streptomyces coelicolor. Among many potential governing factors on pH variation, the putative Na(+)/H(+) antiporter (sha) genes in S. coelicolor have been investigated in this study to elucidate the association of the sha on pH variation and secondary metabolism. Through the transcriptional analysis and overexpression experiments on 8 sha genes, we observed that most of the sha expressions were promoted by pH shock, and in the opposite way the pH changes and actinorhodin production were enhanced by the overexpression of each sha. We also confirmed that sha8 especially has a main role in maintaining cell viability and pH homeostasis through Na(+) extrusion, in salt effect experiment under the alkaline medium condition by deleting sha8. Moreover, this gene was observed to have a function of pH recovery after pH variation such as the pH shock, being able to cause the sporulation. However, actinorhodin production was not induced by the only pH recovery. The sha8 gene could confer on the host cell the ability to recover pH to the neutral level after pH variation like a pH drop. Sporulation was closely associated with this pH recovery caused by the action of sha8, whereas actinorhodin production was not due to such pH variation patterns alone.

  6. Gamma-Glutamylpolyamine Synthetase GlnA3 Is Involved in the First Step of Polyamine Degradation Pathway in Streptomyces coelicolor M145

    Directory of Open Access Journals (Sweden)

    Agnieszka Bera

    2017-04-01

    Full Text Available Streptomyces coelicolor M145 was shown to be able to grow in the presence of high concentrations of polyamines, such as putrescine, cadaverine, spermidine, or spermine, as a sole nitrogen source. However, hardly anything is known about polyamine utilization and its regulation in streptomycetes. In this study, we demonstrated that only one of the three proteins annotated as glutamine synthetase-like protein, GlnA3 (SCO6962, was involved in the catabolism of polyamines. Transcriptional analysis revealed that the expression of glnA3 was strongly induced by exogenous polyamines and repressed in the presence of ammonium. The ΔglnA3 mutant was shown to be unable to grow on defined Evans agar supplemented with putrescine, cadaverine, spermidine, and spermine as sole nitrogen source. HPLC analysis demonstrated that the ΔglnA3 mutant accumulated polyamines intracellularly, but was unable to degrade them. In a rich complex medium supplemented with a mixture of the four different polyamines, the ΔglnA3 mutant grew poorly showing abnormal mycelium morphology and decreased life span in comparison to the parental strain. These observations indicated that the accumulation of polyamines was toxic for the cell. An in silico analysis of the GlnA3 protein model suggested that it might act as a gamma-glutamylpolyamine synthetase catalyzing the first step of polyamine degradation. GlnA3-catalyzed glutamylation of putrescine was confirmed in an enzymatic in vitro assay and the GlnA3 reaction product, gamma-glutamylputrescine, was detected by HPLC/ESI-MS. In this work, the first step of polyamine utilization in S. coelicolor has been elucidated and the putative polyamine utilization pathway has been deduced based on the sequence similarity and transcriptional analysis of homologous genes expressed in the presence of polyamines.

  7. One of the Two Genes Encoding Nucleoid-Associated HU Proteins in Streptomyces coelicolor Is Developmentally Regulated and Specifically Involved in Spore Maturation▿ †

    Science.gov (United States)

    Salerno, Paola; Larsson, Jessica; Bucca, Giselda; Laing, Emma; Smith, Colin P.; Flärdh, Klas

    2009-01-01

    Streptomyces genomes encode two homologs of the nucleoid-associated HU proteins. One of them, here designated HupA, is of a conventional type similar to E. coli HUα and HUβ, while the other, HupS, is a two-domain protein. In addition to the N-terminal part that is similar to that of HU proteins, it has a C-terminal domain that is similar to the alanine- and lysine-rich C termini of eukaryotic linker histones. Such two-domain HU proteins are found only among Actinobacteria. In this phylum some organisms have only a single HU protein of the type with a C-terminal histone H1-like domain (e.g., Hlp in Mycobacterium smegmatis), while others have only a single conventional HU. Yet others, including the streptomycetes, produce both types of HU proteins. We show here that the two HU genes in Streptomyces coelicolor are differentially regulated and that hupS is specifically expressed during sporulation, while hupA is expressed in vegetative hyphae. The developmental upregulation of hupS occurred in sporogenic aerial hyphal compartments and was dependent on the developmental regulators whiA, whiG, and whiI. HupS was found to be nucleoid associated in spores, and a hupS deletion mutant had an average nucleoid size in spores larger than that in the parent strain. The mutant spores were also defective in heat resistance and spore pigmentation, although they possessed apparently normal spore walls and displayed no increased sensitivity to detergents. Overall, the results show that HupS is specifically involved in sporulation and may affect nucleoid architecture and protection in spores of S. coelicolor. PMID:19717607

  8. Role of an Essential Acyl Coenzyme A Carboxylase in the Primary and Secondary Metabolism of Streptomyces coelicolor A3(2)

    Science.gov (United States)

    Rodríguez, E.; Banchio, C.; Diacovich, L.; Bibb, M. J.; Gramajo, H.

    2001-01-01

    Two genes, accB and accE, that form part of the same operon, were cloned from Streptomyces coelicolor A3(2). AccB is homologous to the carboxyl transferase domain of several propionyl coezyme A (CoA) carboxylases and acyl-CoA carboxylases (ACCases) of actinomycete origin, while AccE shows no significant homology to any known protein. Expression of accB and accE in Escherichia coli and subsequent in vitro reconstitution of enzyme activity in the presence of the biotinylated protein AccA1 or AccA2 confirmed that AccB was the carboxyl transferase subunit of an ACCase. The additional presence of AccE considerably enhanced the activity of the enzyme complex, suggesting that this small polypeptide is a functional component of the ACCase. The impossibility of obtaining an accB null mutant and the thiostrepton growth dependency of a tipAp accB conditional mutant confirmed that AccB is essential for S. coelicolor viability. Normal growth phenotype in the absence of the inducer was restored in the conditional mutant by the addition of exogenous long-chain fatty acids in the medium, indicating that the inducer-dependent phenotype was specifically related to a conditional block in fatty acid biosynthesis. Thus, AccB, together with AccA2, which is also an essential protein (E. Rodriguez and H. Gramajo, Microbiology 143:3109–3119, 1999), are the most likely components of an ACCase whose main physiological role is the synthesis of malonyl-CoA, the first committed step of fatty acid synthesis. Although normal growth of the conditional mutant was restored by fatty acids, the cultures did not produce actinorhodin or undecylprodigiosin, suggesting a direct participation of this enzyme complex in the supply of malonyl-CoA for the synthesis of these secondary metabolites. PMID:11526020

  9. Fungal cultivation on glass-beads

    DEFF Research Database (Denmark)

    Droce, Aida; Sørensen, Jens Laurids; Giese, Henriette

    Transcription of various bioactive compounds and enzymes are dependent on fungal cultivation method. In this study we cultivate Fusarium graminearum and Fusarium solani on glass-beads with liquid media in petri dishes as an easy and inexpensive cultivation method, that resembles in secondary...... metabolite production to agar-cultivation but with an easier and more pure RNA-extraction of total fungal mycelia....

  10. Cultivation and uses of cucurbits

    Science.gov (United States)

    Cultivated cucurbits have spread through trade and exploration from their respective Old and New World centers of origin to the six arable continents and are important in local, regional and world trade. Cucumber (Cucumis sativus L.), melon (Cucumis melo L.), pumpkin, squash and gourd (Cucurbita spp...

  11. Cultivating Audiences: Taming, Teaching, Transforming

    Science.gov (United States)

    Nicolucci, Sandra

    2010-01-01

    Satisfying and successful school concerts require an active, empathic, and cooperative partnership between performers and audience members. As music educators work to prepare artful, dignified, and confident performers, "audiences" for these performers must be cultivated just as purposefully. Concertgoers can be motivated to consume school…

  12. Sustainable intensification of cultivated pastures using multiple ...

    African Journals Online (AJOL)

    rangeland and wildlife parks) for guidelines to implementing this approach in cultivated pasture. In rangeland or natural grassland ... Keywords: animal production, biodiversity, cultivated pastures, foraging ecology, plant–herbivore interactions ...

  13. Exploring the Cultivable Ectocarpus Microbiome.

    Science.gov (United States)

    KleinJan, Hetty; Jeanthon, Christian; Boyen, Catherine; Dittami, Simon M

    2017-01-01

    Coastal areas form the major habitat of brown macroalgae, photosynthetic multicellular eukaryotes that have great ecological value and industrial potential. Macroalgal growth, development, and physiology are influenced by the microbial community they accommodate. Studying the algal microbiome should thus increase our fundamental understanding of algal biology and may help to improve culturing efforts. Currently, a freshwater strain of the brown macroalga Ectocarpus subulatus is being developed as a model organism for brown macroalgal physiology and algal microbiome studies. It can grow in high and low salinities depending on which microbes it hosts. However, the molecular mechanisms involved in this process are still unclear. Cultivation of Ectocarpus -associated bacteria is the first step toward the development of a model system for in vitro functional studies of brown macroalgal-bacterial interactions during abiotic stress. The main aim of the present study is thus to provide an extensive collection of cultivable E . subulatus -associated bacteria. To meet the variety of metabolic demands of Ectocarpus -associated bacteria, several isolation techniques were applied, i.e., direct plating and dilution-to-extinction cultivation techniques, each with chemically defined and undefined bacterial growth media. Algal tissue and algal growth media were directly used as inoculum, or they were pretreated with antibiotics, by filtration, or by digestion of algal cell walls. In total, 388 isolates were identified falling into 33 genera (46 distinct strains), of which Halomonas ( Gammaproteobacteria ), Bosea ( Alphaproteobacteria ), and Limnobacter ( Betaproteobacteria ) were the most abundant. Comparisons with 16S rRNA gene metabarcoding data showed that culturability in this study was remarkably high (∼50%), although several cultivable strains were not detected or only present in extremely low abundance in the libraries. These undetected bacteria could be considered as part

  14. Exploring the Cultivable Ectocarpus Microbiome

    Directory of Open Access Journals (Sweden)

    Hetty KleinJan

    2017-12-01

    Full Text Available Coastal areas form the major habitat of brown macroalgae, photosynthetic multicellular eukaryotes that have great ecological value and industrial potential. Macroalgal growth, development, and physiology are influenced by the microbial community they accommodate. Studying the algal microbiome should thus increase our fundamental understanding of algal biology and may help to improve culturing efforts. Currently, a freshwater strain of the brown macroalga Ectocarpus subulatus is being developed as a model organism for brown macroalgal physiology and algal microbiome studies. It can grow in high and low salinities depending on which microbes it hosts. However, the molecular mechanisms involved in this process are still unclear. Cultivation of Ectocarpus-associated bacteria is the first step toward the development of a model system for in vitro functional studies of brown macroalgal–bacterial interactions during abiotic stress. The main aim of the present study is thus to provide an extensive collection of cultivable E. subulatus-associated bacteria. To meet the variety of metabolic demands of Ectocarpus-associated bacteria, several isolation techniques were applied, i.e., direct plating and dilution-to-extinction cultivation techniques, each with chemically defined and undefined bacterial growth media. Algal tissue and algal growth media were directly used as inoculum, or they were pretreated with antibiotics, by filtration, or by digestion of algal cell walls. In total, 388 isolates were identified falling into 33 genera (46 distinct strains, of which Halomonas (Gammaproteobacteria, Bosea (Alphaproteobacteria, and Limnobacter (Betaproteobacteria were the most abundant. Comparisons with 16S rRNA gene metabarcoding data showed that culturability in this study was remarkably high (∼50%, although several cultivable strains were not detected or only present in extremely low abundance in the libraries. These undetected bacteria could be considered

  15. Synthesis of silver nanoparticles using the Streptomyces coelicolor klmp33 pigment: An antimicrobial agent against extended-spectrum beta-lactamase (ESBL) producing Escherichia coli

    International Nuclear Information System (INIS)

    Manikprabhu, Deene; Lingappa, K.

    2014-01-01

    The increasing emergence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli) occurred mainly due to continuous persistent exposure to antibiotics causing high morbidity and mortality so studies in controlling this infection are required. In the present investigation, we developed a synthesis for silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33, and assessed the antimicrobial activity of these nanoparticles against ESBL producing E. coli. The ESBL producing E. coli were isolated from urine samples collected from the Gulbarga region in India. As can been seen from our studies, the silver nanoparticles having irregular shapes and size of 28–50 nm showed remarkable antimicrobial activity and moreover the synthesis time is just 20 min and thus the same can be used for formulating pharmaceutical remedies. - Highlights: • Silver nanoparticle synthesis by photo-irradiation method in just 20 min • Isolation of ESBL producing E. coli from urine samples from the Gulbarga region. • Antimicrobial activity of silver nanoparticles against ESBL producing E. coli • The minimum inhibitory concentration of silver nanoparticles against ESBL producing E. coli was 40 μL

  16. Synthesis of silver nanoparticles using the Streptomyces coelicolor klmp33 pigment: An antimicrobial agent against extended-spectrum beta-lactamase (ESBL) producing Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Manikprabhu, Deene; Lingappa, K., E-mail: lingappak123@gmail.com

    2014-12-01

    The increasing emergence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli) occurred mainly due to continuous persistent exposure to antibiotics causing high morbidity and mortality so studies in controlling this infection are required. In the present investigation, we developed a synthesis for silver nanoparticles employing a pigment produced by Streptomyces coelicolor klmp33, and assessed the antimicrobial activity of these nanoparticles against ESBL producing E. coli. The ESBL producing E. coli were isolated from urine samples collected from the Gulbarga region in India. As can been seen from our studies, the silver nanoparticles having irregular shapes and size of 28–50 nm showed remarkable antimicrobial activity and moreover the synthesis time is just 20 min and thus the same can be used for formulating pharmaceutical remedies. - Highlights: • Silver nanoparticle synthesis by photo-irradiation method in just 20 min • Isolation of ESBL producing E. coli from urine samples from the Gulbarga region. • Antimicrobial activity of silver nanoparticles against ESBL producing E. coli • The minimum inhibitory concentration of silver nanoparticles against ESBL producing E. coli was 40 μL.

  17. Hydroponic cultivation of Oncidium baueri

    Directory of Open Access Journals (Sweden)

    Daniele Brandstetter Rodrigues

    2017-08-01

    Full Text Available In Brazil, orchid cultivation has been increasing steadily over the last few years and contributing significantly to the economy. It has been reported that several vegetable crops and ornamentals have been successfully grown by soilless cultivation. The orchid Oncidium baueri Lindl. is grown on pot substrates. Nevertheless, hydroponics is an excellent alternative, especially for the production of cut flowers and bare root plants. The objective of this study was to evaluate the development of Oncidium baueri on two soilless systems: (a pots containing Amafibra® coconut fiber, carbonized rice husk, and pine bark (1:1:1 irrigated with nutrient solution every 15 d; and (b a nutrient film technique (NFT hydroponic system irrigated with nutrient solution daily. Shoot height, pseudobulb diameter, and number of sprouts were evaluated monthly. The number of flowering plants, number of flowers, dry mass of shoots, and dry mass of roots were evaluated 11 months after onset of experiment. The pot cultivation system yielded more flowers and higher values for all vegetative parameters than the NFT hydroponic system.

  18. Cultivating the Deep Subsurface Microbiome

    Science.gov (United States)

    Casar, C. P.; Osburn, M. R.; Flynn, T. M.; Masterson, A.; Kruger, B.

    2017-12-01

    Subterranean ecosystems are poorly understood because many microbes detected in metagenomic surveys are only distantly related to characterized isolates. Cultivating microorganisms from the deep subsurface is challenging due to its inaccessibility and potential for contamination. The Deep Mine Microbial Observatory (DeMMO) in Lead, SD however, offers access to deep microbial life via pristine fracture fluids in bedrock to a depth of 1478 m. The metabolic landscape of DeMMO was previously characterized via thermodynamic modeling coupled with genomic data, illustrating the potential for microbial inhabitants of DeMMO to utilize mineral substrates as energy sources. Here, we employ field and lab based cultivation approaches with pure minerals to link phylogeny to metabolism at DeMMO. Fracture fluids were directed through reactors filled with Fe3O4, Fe2O3, FeS2, MnO2, and FeCO3 at two sites (610 m and 1478 m) for 2 months prior to harvesting for subsequent analyses. We examined mineralogical, geochemical, and microbiological composition of the reactors via DNA sequencing, microscopy, lipid biomarker characterization, and bulk C and N isotope ratios to determine the influence of mineralogy on biofilm community development. Pre-characterized mineral chips were imaged via SEM to assay microbial growth; preliminary results suggest MnO2, Fe3O4, and Fe2O3 were most conducive to colonization. Solid materials from reactors were used as inoculum for batch cultivation experiments. Media designed to mimic fracture fluid chemistry was supplemented with mineral substrates targeting metal reducers. DNA sequences and microscopy of iron oxide-rich biofilms and fracture fluids suggest iron oxidation is a major energy source at redox transition zones where anaerobic fluids meet more oxidizing conditions. We utilized these biofilms and fluids as inoculum in gradient cultivation experiments targeting microaerophilic iron oxidizers. Cultivation of microbes endemic to DeMMO, a system

  19. Plants cultivation in controlled containments

    International Nuclear Information System (INIS)

    2000-01-01

    The plants cultivation in controlled containments permits to the - Departement d'Ecophysiologie Vegetale et de Microbiologie (DVEM) - of the CEA to lead several topics of research. The works of DVEM which are based on the molecular labelling, technique adapted to plants, contribute to understand the plant - soil relationships and the plant growth process. In addition, the staff of DVEM study the impact of pollutant heavy metals, existing in the soil, on plants and the plant stress induced by oxygen, light, ionizing radiations,... and defence mechanisms of plants (F. M.)

  20. ADAPTIVE ENERGY-SAVING CULTIVATOR FOR STONY SOILS CULTIVATING

    Directory of Open Access Journals (Sweden)

    A. B. Kudzaev

    2015-01-01

    Full Text Available Practice of cultivators operation on stony soils in RNO-Alania with high hardness and humidity indicates that traction resistance during the work varies widely, with deviation from the mean value by more than 2 times. Optimally adjust the machine to the soil background when using most modern mechanisms of regulation is not always possible. Customizing the data machine boils down to the choice of priority between the vibration of the working bodies in the soil, the maintenance of the given depth and power reserve stands required to crawl the working body of the big stones. It is very difficult to get in practice the best combination of these three factors, especially on stony soils. Therefore, the machine must be designed with the ability to quickly adjust to changing operating conditions and modes to ensure energy-saving effects and not violations of the specified soil depth of various hardness with the possibility of equipping the machine racks with different working bodies. The interrow cultivator with the possibility of the quick adjustment (including automated to varying conditions was developed. In the process of studied basic parameters of elastic composite racks and parameters of pneumatic mechanism drive to adjust the proposed section of the machine were established. The system hardiness in layouts by elastic bars with air pressure up to 0.6 MPa varies from 17.7 to 45.3 N/mm. It was received effective values of pressures 0.4-0.5 MPa in the pneumatic drive partitions of the machine when operating with universal blade and ridger body OK-3 on stony soil. As a result, traction resistance decreases by 30-35 percent.

  1. Mixotrophic cultivation of microalgae for biodiesel production: status and prospects.

    Science.gov (United States)

    Wang, Jinghan; Yang, Haizhen; Wang, Feng

    2014-04-01

    Biodiesel from microalgae provides a promising alternative for biofuel production. Microalgae can be produced under three major cultivation modes, namely photoautotrophic cultivation, heterotrophic cultivation, and mixotrophic cultivation. Potentials and practices of biodiesel production from microalgae have been demonstrated mostly focusing on photoautotrophic cultivation; mixotrophic cultivation of microalgae for biodiesel production has rarely been reviewed. This paper summarizes the mechanisms and virtues of mixotrophic microalgae cultivation through comparison with other major cultivation modes. Influencing factors of microalgal biodiesel production under mixotrophic cultivation are presented, development of combining microalgal biodiesel production with wastewater treatment is especially reviewed, and bottlenecks and strategies for future commercial production are also identified.

  2. Multiple outcomes of cultivation in the Sahel

    DEFF Research Database (Denmark)

    Rasmussen, Laura Vang; Reenberg, Anette

    2015-01-01

    A default assumption about the Sahel is that farmers consider food provision for the family as the sole reason for cultivation. The degree to which this ‘cultivation for food’ assumption has been embedded in the scientific literature on land use changes is signified by the fact that hardly any...

  3. Shifting Cultivation : Promoting Innovative Policy and Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Shifting Cultivation : Promoting Innovative Policy and Development Options in the Eastern Himalayas. Shifting ... pressure and market forces. The idea is to share good policies and practices related to shifting cultivation and alternative options through regional exchange. ... Les chaînes de valeur comme leviers stratégiques.

  4. Identifying conditions for inducible protein production in E. coli: combining a fed-batch and multiple induction approach

    Directory of Open Access Journals (Sweden)

    Choi Young J

    2006-08-01

    Full Text Available Abstract Background In the interest of generating large amounts of recombinant protein, inducible systems have been studied to maximize both the growth of the culture and the production of foreign proteins. Even though thermo-inducible systems were developed in the late 1970's, the number of studies that focus on strategies for the implementation at bioreactor scale is limited. In this work, the bacteriophage lambda PL promoter is once again investigated as an inducible element but for the production of green fluorescent protein (GFP. Culture temperature, induction point, induction duration and number of inductions were considered as factors to maximize GFP production in a 20-L bioreactor. Results It was found that cultures carried out at 37°C resulted in a growth-associated production of GFP without the need of an induction at 42°C. Specific production was similar to what was achieved when separating the growth and production phases. Shake flask cultures were used to screen for desirable operating conditions. It was found that multiple inductions increased the production of GFP. Induction decreased the growth rate and substrate yield coefficients; therefore, two time domains (before and after induction having different kinetic parameters were created to fit a model to the data collected. Conclusion Based on two batch runs and the simulation of culture dynamics, a pre-defined feeding and induction strategy was developed to increase the volumetric yield of a temperature regulated expression system and was successfully implemented in a 20-L bioreactor. An overall cell density of 5.95 g DW l-1 was achieved without detriment to the cell specific production of GFP; however, the production of GFP was underestimated in the simulations due to a significant contribution of non-growth associated product formation under limiting nutrient conditions.

  5. pH-oscillations in the bromate–sulfite reaction in semibatch and in gel-fed batch reactors

    Energy Technology Data Exchange (ETDEWEB)

    Poros, Eszter; Kurin-Csörgei, Krisztina; Szalai, István; Orbán, Miklós, E-mail: orbanm@chem.elte.hu [Department of Analytical Chemistry, Institute of Chemistry, L. Eötvös University, P.O. Box 32, H-1518 Budapest 112 (Hungary); Rábai, Gyula [Institute of Physical Chemistry, University of Debrecen, P.O. Box 7, H-4010 Debrecen (Hungary)

    2015-06-15

    The simplest bromate oxidation based pH-oscillator, the two component BrO{sub 3}{sup −}–SO{sub 3}{sup 2–} flow system was transformed to operate under semibatch and closed arrangements. The experimental preconditions of the pH-oscillations in semibatch configuration were predicted by model calculations. Using this information as guideline large amplitude (ΔpH∼3), long lasting (11–24 h) pH-oscillations accompanied with only a 20% increase of the volume in the reactor were measured when a mixture of Na{sub 2}SO{sub 3} and H{sub 2}SO{sub 4} was pumped into the solution of BrO{sub 3}{sup −} with a very low rate. Batch-like pH-oscillations, similar in amplitude and period time appeared when the sulfite supply was substituted by its dissolution from a gel layer prepared previously in the reactor in presence of high concentration of Na{sub 2}SO{sub 3}. The dissolution vs time curve and the pH-oscillations in the semibatch and closed systems were successfully simulated. Due to the simplicity in composition and in experimental technique, the semibatch and batch-like BrO{sub 3}{sup −}–SO{sub 3}{sup 2–} pH-oscillators may become superior to their CSTR (continuous flow stirred tank reactor) version in some present and future applications.

  6. pH-oscillations in the bromate-sulfite reaction in semibatch and in gel-fed batch reactors

    Science.gov (United States)

    Poros, Eszter; Kurin-Csörgei, Krisztina; Szalai, István; Rábai, Gyula; Orbán, Miklós

    2015-06-01

    The simplest bromate oxidation based pH-oscillator, the two component BrO3--SO32- flow system was transformed to operate under semibatch and closed arrangements. The experimental preconditions of the pH-oscillations in semibatch configuration were predicted by model calculations. Using this information as guideline large amplitude (ΔpH˜3), long lasting (11-24 h) pH-oscillations accompanied with only a 20% increase of the volume in the reactor were measured when a mixture of Na2SO3 and H2SO4 was pumped into the solution of BrO3- with a very low rate. Batch-like pH-oscillations, similar in amplitude and period time appeared when the sulfite supply was substituted by its dissolution from a gel layer prepared previously in the reactor in presence of high concentration of Na2SO3. The dissolution vs time curve and the pH-oscillations in the semibatch and closed systems were successfully simulated. Due to the simplicity in composition and in experimental technique, the semibatch and batch-like BrO3--SO32- pH-oscillators may become superior to their CSTR (continuous flow stirred tank reactor) version in some present and future applications.

  7. Improved production of an enzyme that hydrolyses raw yam starch by Penicillium sp. S-22 using fed-batch fermentation.

    Science.gov (United States)

    Sun, Hai-Yan; Ge, Xiang-Yang; Zhang, Wei-Guo

    2006-11-01

    A newly isolated strain, Penicillium sp. S-22, was used to produce an enzyme that hydrolyses raw yam starch [raw yam starch digesting enzyme (RYSDE)]. The enzyme activity and overall enzyme productivity were respectively 16 U/ml and 0.19 U/ml h in the batch culture. The enzyme activity increased to 85 U/ml by feeding of partially hydrolyzed raw yam starch. When a mixture containing partially hydrolyzed raw yam starch and peptone was fed by a pH-stat strategy, the enzyme activity reached 366 U/ml, 23-fold of that obtained in the batch culture, and the overall productivity reached 3.4 U/ml h, which was 18-fold of that in the batch culture.

  8. Ethanol production from biomass by repetitive solid-state fed-batch fermentation with continuous recovery of ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Moukamnerd, Churairat; Kino-oka, Masahiro; Sugiyama, Minetaka; Kaneko, Yoshinobu; Harashima, Satoshi; Katakura, Yoshio [Osaka Univ. (Japan). Dept. of Biotechnology; Boonchird, Chuenchit [Mahidol Univ., Bangkok (Thailand). Dept. of Biotechnology; Noda, Hideo [Kansai Chemical Engineering Co., Ltd., Amagasaki (Japan); Ninomiya, Kazuaki [Kanazawa Univ. (Japan). Inst. of International Environment Technology; Shioya, Suteaki [Sojo Univ., Kumamoto (Japan). Dept. of Applied Life Science

    2010-09-15

    To save cost and input energy for bioethanol production, a consolidated continuous solid-state fermentation system composed of a rotating drum reactor, a humidifier, and a condenser was developed. Biomass, saccharifying enzymes, yeast, and a minimum amount of water are introduced into the system. Ethanol produced by simultaneous saccharification and fermentation is continuously recovered as vapor from the headspace of the reactor, while the humidifier compensates for the water loss. From raw corn starch as a biomass model, 95 {+-} 3, 226 {+-} 9, 458 {+-} 26, and 509 {+-} 64 g l{sup -1} of ethanol solutions were recovered continuously when the ethanol content in reactor was controlled at 10-20, 30-50, 50-70 and 75-85 g kg-mixture{sup -1}, respectively. The residue showed a lesser volume and higher solid content than that obtained by conventional liquid fermentation. The cost and energy for intensive waste water treatment are decreased, and the continuous fermentation enabled the sustainability of enzyme activity and yeast in the system. (orig.)

  9. Response coefficient analysis of a fed-batch bioreactor to dissolved oxygen perturbation in complementary cultures during PHB production

    Directory of Open Access Journals (Sweden)

    Patnaik Pratap R

    2008-03-01

    Full Text Available Abstract Background Although the production of poly-β-hydroxybutyrate (PHB has many biological, energetic and environmental advantages over chemically synthesized polymers, synthetic polymers continue to be produced industrially since the productivities of fermentation processes fr PHB are not yet economically competitive. Improvement of a PHB fermentation requires good understanding and optimization under the realistic conditions of large bioreactors. Laboratory-scale studies have shown that co-cultures of Ralstonia eutropha and Lactobacillus delbrueckii generate better fermentation efficiencies than R. eutropha alone. In large bioreactors, incomplete dispersioin and perturbations in the dissolved oxygen (DO concentration, both of which affect the fermentation, have to be considered. This study analyzes the effect of DO fluctuations on bioreactor performance for both ideal and optimally dispersed broths. Results Response coefficient analysis was employed to obtain quantitative information on the effect of DO perturbations on different variables. Three values of the Peclet number (Pe cheracterized three levels of dispersion: Pe = 0.01 for nearly complete dispersion, Pe = 20 for optimum dispersion and Pe = 60 for insufficient dispersion. The response coefficients (RCs of the pairs of bacterial concentrations and the main substrates, glucose and ammonium chloride, showed contrasting variations with time. Lactate, a critical intermediate, and PHB had similar RC profiles but those of lactate were one to two orders of magnitude larger than other RCs. Significantly, the optimum Pe also resulted in the largest RCs, suggesting a balance between productivity and reactor stability. Conclusion Since R. eutropha requires oxygen for its growth whereas L. delbrueckii does not, fluctuations in the DO concentartion have a strong influence on the fermentation. Apart from this, the mechanism of PHB biosynthesis indicates that control of lactate is a critical determinant of fermentation efficiency. The RC profiles indicate that, under non-ideal conditions, a compromise may be required between PHB formation and reactor stability, especially in the latter half of the process.

  10. Differential expression of small RNAs under chemical stress and fed-batch fermentation in E. coli

    DEFF Research Database (Denmark)

    Rau, Martin Holm; Nielsen, Alex Toftgaard; Long, Katherine

    2015-01-01

    Bacterial small RNAs (sRNAs) are recognized as posttranscriptional regulators involved in the control of bacterial lifestyle and adaptation to stressful conditions. Although chemical stress due to the toxicity of precursor and product compounds is frequently encountered in microbial bioprocessing...

  11. New pleiotropic effects of eliminating a rare tRNA from Streptomyces coelicolor, revealed by combined proteomic and transcriptomic analysis of liquid cultures

    Directory of Open Access Journals (Sweden)

    Hotchkiss Graham

    2007-08-01

    Full Text Available Abstract Background In Streptomyces coelicolor, bldA encodes the only tRNA for a rare leucine codon, UUA. This tRNA is unnecessary for growth, but is required for some aspects of secondary metabolism and morphological development. We describe a transcriptomic and proteomic analysis of the effects of deleting bldA on cellular processes during submerged culture: conditions relevant to the industrial production of antibiotics. Results At the end of rapid growth, a co-ordinated transient up-regulation of about 100 genes, including many for ribosomal proteins, was seen in the parent strain but not the ΔbldA mutant. Increased basal levels of the signal molecule ppGpp in the mutant strain may be responsible for this difference. Transcripts or proteins from a further 147 genes classified as bldA-influenced were mostly expressed late in culture in the wild-type, though others were significantly transcribed during exponential growth. Some were involved in the biosynthesis of seven secondary metabolites; and some have probable roles in reorganising metabolism after rapid growth. Many of the 147 genes were "function unknown", and may represent unknown aspects of Streptomyces biology. Only two of the 147 genes contain a TTA codon, but some effects of bldA could be traced to TTA codons in regulatory genes or polycistronic operons. Several proteins were affected post-translationally by the bldA deletion. There was a statistically significant but weak positive global correlation between transcript and corresponding protein levels. Different technical limitations of the two approaches were a major cause of discrepancies in the results obtained with them. Conclusion Although deletion of bldA has very conspicuous effects on the gross phenotype, the bldA molecular phenotype revealed by the "dualomic" approach has shown that only about 2% of the genome is affected; but this includes many previously unknown effects at a variety of different levels, including post

  12. Improving Former Shifted Cultivation Land Using Wetland Cultivation in Kapuas District, Central Kalimantan

    Directory of Open Access Journals (Sweden)

    Wahyudi Wahyudi

    2016-06-01

    Full Text Available Degraded forest area in Kalimantan could be caused by shifted cultivation activity that be conducted by local peoples in the surrounding forest areas. Efforts to improve the former shifted cultivation area (non productive land is developing the settled cultivation by use of irrigation system, better paddy seed, land processing, fertilizing, spraying pesticide, weeding, and better acces to the market.  Local peoples, especially in Kalimantan, has been depended their food on the shifted cultivation pattern since the long time ago.  This tradition could cause forest damage, forest fire, forest degradation, deforestation, and lose out of children education because they were following shifted cultivation activity although itsspace is very far from their home.  This research was aimed to improve former shifted cultivation lands using wetland cultivation in order to improve land productivity and to support food securityin the local community. This research was administratively located in Tanjung Rendan Village, Kapuas Hulu Sub-Ddistrict, Kapuas District, Central Kalimantan Province, Indonesia.  Data of rice yield from settled cultivation and shifted cultivation were got from 15 households that was taking by random at 2010 to 2011. Homogeneity test, analysis of variants, and least significant different (LSD test using SPSS 15.0 for Windows. Result of this research showed that     paddy yield at settled cultivation was significantly differentand better than shifted cultivation at 0.05 level. LSD test also indicated that all paddy yields from settled cultivation were significantly different compare to shifted cultivation at the 0.05 level.  The community in Tanjung Rendan Villages preferred settled cultivation than shifted cultivation, especially due to higher paddy production. Profit for settled cultivation was IDR10.95 million ha-1, meanwhile profit for shifted cultivation was just IDR 2.81 million ha-1 only.  Settled cultivation pattern could

  13. Shifting Cultivation : Promoting Innovative Policy and Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... if improved and rationalized as an agroforestry system, has high potential for poverty ... with the livelihood issues of the cultivators and the health of the ecosystem, and assess the ... International Centre for Integrated Mountain Development.

  14. Soilless cultivation system for functional food crops

    International Nuclear Information System (INIS)

    Ahamad Sahali Mardi; Shyful Azizi Abdul Rahman; Ahmad Nazrul Abd Wahid; Abdul Razak Ruslan; Hazlina Abdullah

    2007-01-01

    This soilless cultivation system is based on the fertigation system and cultivation technologies using Functional Plant Cultivation System (FPCS). EBARA Japan has been studying on the cultivation conditions in order to enhance the function of decease risk reduction in plants. Through the research and development activities, EBARA found the possibilities on the enhancement of functions. Quality and quantity of the products in term of bioactive compounds present in the plants may be affected by unforeseen environmental conditions, such as temperature, strong light and UV radiation. The main objective to develop this system is, to support? Functional Food Industry? as newly emerging field in agriculture business. To success the system, needs comprehensive applying agriculture biotechnologies, health biotechnologies and also information technologies, in agriculture. By this system, production of valuable bioactive compounds is an advantage, because the market size of functional food is increasing more and more in the future. (Author)

  15. Cultivation of parasitic leptospires: effect of pyruvate.

    Science.gov (United States)

    Johnson, R C; Walby, J; Henry, R A; Auran, N E

    1973-07-01

    Sodium pyruvate (100 mug/ml) is a useful addition to the Tween 80-albumin medium for the cultivation of parasitic serotypes. It is most effective in promoting growth from small inocula and growth of the nutritionally fastidious serotypes.

  16. Advancing gut microbiome research using cultivation

    DEFF Research Database (Denmark)

    Sommer, Morten OA

    2015-01-01

    Culture-independent approaches have driven the field of microbiome research and illuminated intricate relationships between the gut microbiota and human health. However, definitively associating phenotypes to specific strains or elucidating physiological interactions is challenging for metagenomic...... approaches. Recently a number of new approaches to gut microbiota cultivation have emerged through the integration of high-throughput phylogenetic mapping and new simplified cultivation methods. These methodologies are described along with their potential use within microbiome research. Deployment of novel...... cultivation approaches should enable improved studies of xenobiotic tolerance and modification phenotypes and allow a drastic expansion of the gut microbiota reference genome catalogues. Furthermore, the new cultivation methods should facilitate systematic studies of the causal relationship between...

  17. How to Cultivate the Student's Cultural Awareness

    Institute of Scientific and Technical Information of China (English)

    tian xiu ying

    2008-01-01

    Language and culture are inseparable and cultural awareness must be integrated with language teaching. How to cultivate the learners' cultural awareness is an important issue that we have to carry out in teaching practice in China.

  18. Effectiveness of Training Programme on Mushroom Cultivation

    OpenAIRE

    Rahman, Md. Sazzadur; Hossain, Kh. Zulfikar; Ali, Md. Sekender; Afroz, Fauzia

    2017-01-01

    Effectiveness is one of the key parameters to assess success of any programs. However, the effectiveness of training programme on mushroom cultivation was not well addressed. The purposes of this study were to investigate the effectiveness of training programme on mushroom cultivation and to explore the relationships of each of the selected characteristics of the trained mushroom farmers with their effectiveness of training programme. Data were collected from the trained mushroom farmers of s...

  19. The Cultivation of Human Granulosa Cells

    Directory of Open Access Journals (Sweden)

    Lenka Brůčková

    2008-01-01

    Full Text Available The major functions of granulosa cells (GCs include the production of steroids, as well as a myriad of growth factors to interact with the oocyte during its development within the ovarian follicle. Also FSH stimulates GCs to convert androgens (coming from the thecal cells to estradiol by aromatase. However, after ovulation the GCs produce progesterone that may maintain a potential pregnancy. Experiments with human GCs are mainly focused on the purification of GCs from ovarian follicular fluid followed by FACS analysis or short-term cultivation. The aim of our study was to cultivate GCs for a long period, to characterize their morphology and phenotype. Moreover, we have cultivated GCs under gonadotropin stimulation in order to simulate different pathological mechanisms during folliculogenesis (e.g. ovarian hyperstimulation syndrome. GCs were harvested from women undergoing in vitro fertilization. Complex oocyte-cumulus oophorus was dissociated by hyaluronidase. The best condition for transport of GCs was optimized as short transport in follicular fluid at 37 °C. GCs expansion medium consisted of DMEM/F12, 2 % FCS, ascorbic acid, dexamethasone, L-glutamine, gentamycine, penicillin, streptomycin and growth factors (EGF, bFGF. GCs transported in follicular fluid and cultivated in 2 % FCS containing DMEM/F12 medium supplemented with follicular fluid presented increased adhesion, proliferation, viability and decreased doubling time. Cell viability was 92 % and mean cell doubling time was 52 hrs. We have optimized transport and cultivation protocols for long-term cultivation of GCs.

  20. The MreB-Like Protein Mbl of Streptomyces coelicolor A3(2) Depends on MreB for Proper Localization and Contributes to Spore Wall Synthesis▿ †

    Science.gov (United States)

    Heichlinger, Andrea; Ammelburg, Moritz; Kleinschnitz, Eva-Maria; Latus, Annette; Maldener, Iris; Flärdh, Klas; Wohlleben, Wolfgang; Muth, Günther

    2011-01-01

    Most bacteria with a rod-shaped morphology contain an actin-like cytoskeleton consisting of MreB polymers, which form helical spirals underneath the cytoplasmic membrane to direct peptidoglycan synthesis for the elongation of the cell wall. In contrast, MreB of Streptomyces coelicolor is not required for vegetative growth but has a role in sporulation. Besides MreB, S. coelicolor encodes two further MreB-like proteins, Mbl and SCO6166, whose function is unknown. Whereas MreB and Mbl are highly similar, SCO6166 is shorter, lacking the subdomains IB and IIB of actin-like proteins. Here, we showed that MreB and Mbl are not functionally redundant but cooperate in spore wall synthesis. Expression analysis by semiquantitative reverse transcription-PCR revealed distinct expression patterns. mreB and mbl are induced predominantly during morphological differentiation. In contrast, sco6166 is strongly expressed during vegetative growth but switched off during sporulation. All genes could be deleted without affecting viability. Even a ΔmreB Δmbl double mutant was viable. Δsco6166 had a wild-type phenotype. ΔmreB, Δmbl, and ΔmreB Δmbl produced swollen, prematurely germinating spores that were sensitive to various kinds of stress, suggesting a defect in spore wall integrity. During aerial mycelium formation, an Mbl-mCherry fusion protein colocalized with an MreB-enhanced green fluorescent protein (MreB-eGFP) fusion protein at the sporulation septa. Whereas MreB-eGFP localized properly in the Δmbl mutant, Mbl-mCherry localization depended on the presence of a functional MreB protein. Our results revealed that MreB and Mbl cooperate in the synthesis of the thickened spore wall, while SCO6166 has a nonessential function during vegetative growth. PMID:21257777

  1. Molecular evidence for the coordination of nitrogen and carbon metabolisms, revealed by a study on the transcriptional regulation of the agl3EFG operon that encodes a putative carbohydrate transporter in Streptomyces coelicolor.

    Science.gov (United States)

    Cen, Xu-Feng; Wang, Jing-Zhi; Zhao, Guo-Ping; Wang, Ying; Wang, Jin

    2016-03-18

    In the agl3EFGXYZ operon (SCO7167-SCO7162, abbreviated as agl3 operon) of Streptomyces coelicolor M145, agl3EFG genes encode a putative ABC-type carbohydrate transporter. The transcription of this operon has been proved to be repressed by Agl3R (SCO7168), a neighboring GntR-family regulator, and this repression can be released by growth on poor carbon sources. Here in this study, we prove that the transcription of agl3 operon is also directly repressed by GlnR, a central regulator governing the nitrogen metabolism in S. coelicolor. The electrophoretic mobility shift assay (EMSA) employing the agl3 promoter and mixtures of purified recombinant GlnR and Agl3R indicates that GlnR and Agl3R bind to different DNA sequences within the promoter region of agl3 operon, which is further confirmed by the DNase I footprinting assay. As Agl3R and GlnR have been demonstrated to sense the extracellular carbon and nitrogen supplies, respectively, it is hypothesized that the transcription of agl3 operon is stringently governed by the availabilities of extracellular carbon and nitrogen sources. Consistent with the hypothesis, the agl3 operon is further found to be derepressed only under the condition of poor carbon and rich nitrogen supplies, when both regulators are inactivated. It is believed that activation of the expression of agl3 operon may facilitate the absorption of extracellular carbohydrates to balance the ratio of intracellular carbon to nitrogen. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Alternative substrates for higher mushrooms mycelia cultivation

    Directory of Open Access Journals (Sweden)

    TETIANA KRUPODOROVA

    2015-12-01

    Full Text Available Cultivation of 29 species of higher mushroom mycelia on alternative substrates – wastes of Ukrainian oil-fat industry, has been investigated. The amount of mushroom mycelia obtaining on 12 investigated substrates varied significantly, from 1.0 g/L to 22.9 g/L on the 14th day of cultivation. The superficial cultivation adopted in this study allows for easy to choose appropriate medium (substrate for mycelia production. Alternative substrates (compared to glucose-peptone-yeast medium were selected for all studied species, from soybean cake – most suitable for the mycelial growth of 24 species, to walnut cake − suitable only for 2 species. The utilization of substrates has been evaluated by biological efficiency. The best index of biological efficiency varied from 19.0% to 41.6% depending on the mushroom species. It was established high biological efficiency of mycelia cultivation on substrates: wheat seed cake – Pleurotus djamor, Lyophyllum shimeji, Crinipellis schevczenkovi, Phellinus igniarius, Spongipellis litschaueri; oat seed cake – Ganoderma applanatum and G. lucidum; soybean cake – Hohenbuehelia myxotricha, Trametes versicolor, Morchella esculenta, Cordyceps sinensis, C. militaris, and Agrocybe aegerita; rape seed cake – Auriporia aurea; camelina seed cake – Fomes fomentarius. The cultivation of these species are perspective as a biotechnological process of agricultural wastes converted into mycelia, which could be used in different forms of products with therapeutic action: powder or tablets nutraceuticals or ingredients for functional foods.

  3. Environmental and nutritional requirements for tea cultivation

    Directory of Open Access Journals (Sweden)

    Hajiboland Roghieh

    2017-12-01

    Full Text Available Tea (Camellia sinensis is an important beverage crop cultivated in the tropics and subtropics under acid soil conditions. Increased awareness of the health-promoting properties of the tea beverage has led to an increase in its level of consumption over the last decades. Tea production contributes significantly to the economy of several tea-cultivating countries in Asia and Africa. Environmental constrains, particularly water deficiency due to inadequate and/or poorly distributed rainfall, seriously limit tea production in the majority of tea-producing countries. It is also predicted that global climate change will have a considerable adverse impact on tea production in the near future. Application of fertilizers for higher production and increased quality and quantity of tea is a common agricultural practice, but due to its environmental consequences, such as groundwater pollution, the rate of fertilizer application needs to be reconsidered. Cultivation of tea under humid conditions renders it highly susceptible to pathogens and pest attacks. Application of pesticides and fungicides adversely affects the quality of tea and increases health risks of the tea beverage. Organic cultivation as an agricultural practice without using synthetic fertilizers and other chemical additives such as pesticides and fungicides is a sustainable and eco-friendly approach to producing healthy tea. A growing number of tea-producing countries are joining organic tea cultivation programmes in order to improve the quality and to maintain the health benefits of the tea produced.

  4. Phenylhydrazines in the cultivated mushroom (Agaricus bisporus)

    DEFF Research Database (Denmark)

    Andersson, H. C.; Gry, Jørn

    2004-01-01

    In 1991, the Nordic Working Group on Food Toxicology and Risk Evaluation (NNT) reviewed the available data on phenylhydrazines naturally occurring in the cultivated mushroom. It was concluded that the mushroom may contain about 500 mg of the hydrazine derivatives per kg fresh weight. The hydrazine...... derivatives as well as extracts of the cultivated mushroom were mutagenic to a variable degree in most of the reported short-term tests. The raw mushroom and several of the hydrazines induced tumours when administered to Swiss mice as reported by American scientists. However, reservations were expressed...... as to the design of the studies. Based on this review, and due to the concern expressed, a Nordic project (coordinated by Jørn Gry, Danish Veterinary and Food Administration) was initiated dealing with toxicological and chemical studies on the cultivated mushroom and its phenylhydrazine derivatives in order...

  5. Zeolites as possible biofortifiers in Maitake cultivation

    Directory of Open Access Journals (Sweden)

    Vunduk Jovana

    2014-01-01

    Full Text Available The levels of Ni, Cu and Mg in Grifola frondosa (also known as Maitake mushroom fruit body produced on zeolite Minazel Plus (MG-supplemented substrate were measured with inductively coupled plasma optical emission spectrometry (ICP-OES. Two different concentrations of MG were added to the substrate for mushroom cultivation. Levels of selected metals were measured in cultivated dry carpophores. The content of Ni increased in fruit bodies produced on supplemented substrate, while in case of Cu, a pronounced decrease was observed. When two different concentrations of MG were implemented, the Mg level showed both positive and negative trend, depending on the applied concentration of zeolite. MG in a concentration of 1% showed the strongest influence on the observed elements in the cultivated fruiting body of Maitake mushroom. [Projekat Ministarstva nauke Republike Srbije, br. 46010

  6. Characterization and cultivation of Psilocybe barrerae

    OpenAIRE

    E. Montiel; J. C. Barragán; I. Tello; V. M. Mora; I. León; D. Martínez

    2008-01-01

    A strain of Psilocybe barrerae (Strophariaceae) was isolated, characterized, and cultivated under laboratory conditions. Mycelial colonies were white to off-white, showing average growth rates of 3.9 mm/day on potato dextrose agar (PDA) and 3.6 mm/day on corn meal agar (CMA). The production of biomass varied from 0.2872 g dry weight/L/day (CMA) to 0.1353 g dry weight/L/day (PDA). One flush of fruit bodies, cultivated on a mixture of sand and compost as substrate, was produced reaching a biolo...

  7. Microgravity cultivation of cells and tissues

    Science.gov (United States)

    Freed, L. E.; Pellis, N.; Searby, N.; de Luis, J.; Preda, C.; Bordonaro, J.; Vunjak-Novakovic, G.

    1999-01-01

    In vitro studies of cells and tissues in microgravity, either simulated by cultivation conditions on earth or actual, during spaceflight, are expected to help identify mechanisms underlying gravity sensing and transduction in biological organisms. In this paper, we review rotating bioreactor studies of engineered skeletal and cardiovascular tissues carried out in unit gravity, a four month long cartilage tissue engineering study carried out aboard the Mir Space Station, and the ongoing laboratory development and testing of a system for cell and tissue cultivation aboard the International Space Station.

  8. The Third Perspective on Shifting Cultivation

    Directory of Open Access Journals (Sweden)

    Sukanya Sharma

    2017-11-01

    Full Text Available ABSTRACT There are two perspectives in which the understanding of food sustainability in the world is entangled. The first perspective which believes that food sustainability can be achieved by technology presents shifting cultivation as a reflection of a lower state of cultural evolution in comparison with more sophisticated societies (O’Brien 2002.The second perspective which believes in culture, in the ‘way of life’ paradigm valorise shifting cultivation as a form of indigenous genius, representing the indigenous people as perhaps the original environmentalist (Bandy et al.1993; Conklin 1957; Grandstaff 1981; Hong 1987. The biasness of both the perspectives is well visible. The task now is to document and evaluate indigenous strategies of shifting cultivation through a process of research and development. This process involves identification of promising indigenous practices, characterization of the practices, validation of the utility of the practice for other communities, extrapolation to other locations, verification with key farmers, and wide-scale extension. This can be treated as the third perspective available to the policy makers. By this, the detrimental effects of shifting cultivation can be mitigated and productivity increased (Mali 2003.

  9. Comparative study of potato cultivation through micropropagation ...

    African Journals Online (AJOL)

    A trial was carried out to evaluate the productivity of Solanum tuberosum L. cultivated through conventional farming and micropropagation method. Survival rate, biomass and tuber yield of both micropropagated and tuber propagated potatoes was evaluated. Survival percentages of potatoes were 90% for conventional ...

  10. Aggregate stability in soils cultivated with eucalyptus

    Science.gov (United States)

    Eucalyptus cultivation has increased in many Brazilian regions. In order to recommend good management practices, it is necessary to understand changes in soil properties where eucalyptus is planted. Aggregate stability analyses have proved to be a useful tool to measure soil effects caused by change...

  11. Cultivating Visionary Leaders to Transform Our World

    Science.gov (United States)

    Coers, Natalie J.

    2018-01-01

    Vision has long been a quality and characteristic defining leadership. To cultivate vision among undergraduate students in a course, the United Nations' Sustainable Development Goals are utilized as a foundation to inspire a vision that connects local service and personal interests to global, complex issues. Students select a goal to work with for…

  12. Cultivation of the bacterium Azotobacter chroococcum for ...

    African Journals Online (AJOL)

    ... increase of bioprocess efficiency parameters (yield coefficient and productivity) were observed compared with the batch cultivation. On the basis of the obtained results, repeated batch technique appeared to be the most suitable for the bacterial biomass production at industrial scale. Key words: Azotobacter chroococcum, ...

  13. Comparative study of potato cultivation through micropropagation ...

    African Journals Online (AJOL)

    sonu

    Comparative study of potato cultivation through micropropagation and conventional farming methods .... and Murate potash were used as fertilizer source of nitrogen, phosphorus and potassium, respectively (Table 1) ..... through Tissue culture- Application and Feasibility. U.S.D.A.,. Beltsville. Agric. Res. Sci. Educ. Admin.

  14. Cultivation of Parasitic Leptospires: Effect of Pyruvate

    Science.gov (United States)

    Johnson, R. C.; Walby, J.; Henry, R. A.; Auran, N. E.

    1973-01-01

    Sodium pyruvate (100 μg/ml) is a useful addition to the Tween 80-albumin medium for the cultivation of parasitic serotypes. It is most effective in promoting growth from small inocula and growth of the nutritionally fastidious serotypes. Images PMID:4580191

  15. Cultivation Theory and Research: A Conceptual Critique.

    Science.gov (United States)

    Potter, W. James

    1993-01-01

    Presents a critical analysis of how cultivation (long-term formation of perceptions and beliefs about the world as a result of exposure to media) has been conceptualized in theory and research. Analyses the construct of television exposure. Suggests revisions for conceptualizing the existing theory and extending it. (RS)

  16. Deforestation and cultivation mobilize mercury from topsoil.

    Science.gov (United States)

    Gamby, Rebecca L; Hammerschmidt, Chad R; Costello, David M; Lamborg, Carl H; Runkle, James R

    2015-11-01

    Terrestrial biomass and soils are a primary global reservoir of mercury (Hg) derived from natural and anthropogenic sources; however, relatively little is known about the fate and stability of Hg in the surface soil reservoir and its susceptibility to change as a result of deforestation and cultivation. In southwest Ohio, we measured Hg concentrations in soils of deciduous old- and new-growth forests, as well as fallow grassland and agricultural soils that had once been forested to examine how, over decadal to century time scales, man-made deforestation and cultivation influence Hg mobility from temperate surface soils. Mercury concentrations in surficial soils were significantly greater in the old-growth than new-growth forest, and both forest soils had greater Hg concentrations than cultivated and fallow fields. Differences in Hg:lead ratios between old-growth forest and agricultural topsoils suggest that about half of the Hg lost from deforested and cultivated Ohio soils may have been volatilized and the other half eroded. The estimated mobilization potential of Hg as a result of deforestation was 4.1 mg m(-2), which was proportional to mobilization potentials measured at multiple locations in the Amazon relative to concentrations in forested surface soils. Based on this relationship and an estimate of the global average of Hg concentrations in forested soils, we approximate that about 550 M mol of Hg has been mobilized globally from soil as a result of deforestation during the past two centuries. This estimate is comparable to, if not greater than, the amount of anthropogenic Hg hypothesized by others to have been sequestered by the soil reservoir since Industrialization. Our results suggest that deforestation and soil cultivation are significant anthropogenic processes that exacerbate Hg mobilization from soil and its cycling in the environment. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. The medicinal Agaricus mushroom cultivated in Brazil: biology, cultivation and non-medicinal valorisation.

    Science.gov (United States)

    Largeteau, Michèle L; Llarena-Hernández, Régulo Carlos; Regnault-Roger, Catherine; Savoie, Jean-Michel

    2011-12-01

    Sun mushroom is a cultivated mushroom extensively studied for its medicinal properties for several years and literature abounds on the topic. Besides, agronomical aspects were investigated in Brazil, the country the mushroom comes from, and some studies focus on the biology of the fungus. This review aimed to present an overview of the non-medicinal knowledge on the mushroom. Areas of commercial production and marketing trends are presented. Its specific fragrance, taste, nutritional value and potential use of extracts as food additives are compared to those of the most cultivated fungi and laboratory models. The interest of the mushroom for lignocellulosic enzyme production and source of biomolecules for the control of plant pathogens are shown. Investigation of genetic variability among cultivars is reported. Growing and storage of mycelium, as well as cultivation conditions (substrate and casing generally based on local products; indoor and outdoor cultivation; diseases and disorders) are described and compared to knowledge on Agaricus bisporus.

  18. Microbe observation and cultivation array (MOCA) for cultivating and analyzing environmental microbiota.

    Science.gov (United States)

    Gao, Weimin; Navarroli, Dena; Naimark, Jared; Zhang, Weiwen; Chao, Shih-Hui; Meldrum, Deirdre R

    2013-01-09

    The use of culture-independent nucleic acid techniques, such as ribosomal RNA gene cloning library analysis, has unveiled the tremendous microbial diversity that exists in natural environments. In sharp contrast to this great achievement is the current difficulty in cultivating the majority of bacterial species or phylotypes revealed by molecular approaches. Although recent new technologies such as metagenomics and metatranscriptomics can provide more functionality information about the microbial communities, it is still important to develop the capacity to isolate and cultivate individual microbial species or strains in order to gain a better understanding of microbial physiology and to apply isolates for various biotechnological applications. We have developed a new system to cultivate bacteria in an array of droplets. The key component of the system is the microbe observation and cultivation array (MOCA), which consists of a Petri dish that contains an array of droplets as cultivation chambers. MOCA exploits the dominance of surface tension in small amounts of liquid to spontaneously trap cells in well-defined droplets on hydrophilic patterns. During cultivation, the growth of the bacterial cells across the droplet array can be monitored using an automated microscope, which can produce a real-time record of the growth. When bacterial cells grow to a visible microcolony level in the system, they can be transferred using a micropipette for further cultivation or analysis. MOCA is a flexible system that is easy to set up, and provides the sensitivity to monitor growth of single bacterial cells. It is a cost-efficient technical platform for bioassay screening and for cultivation and isolation of bacteria from natural environments.

  19. Evaluation of cellulosic wastes for the cultivation of Pleurotus eryngii ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-05-16

    May 16, 2008 ... of plant residues, and they have been found to be nutritionally and ... In most countries, there is a well-established consumer accep- tance for cultivated ... temperature, dampness, CO2, cultivation methods and tecniques etc.

  20. Bioremediation of industrial waste through mushroom cultivation.

    Science.gov (United States)

    Kulshreshtha, Shweta; Mathur, Nupur; Bhatnagar, Pradeep; Jain, B L

    2010-07-01

    Handmade paper and cardboard industries are involved in processing of cellulosic and ligno-cellulosic substances for making paper by hand or simple machinery. In the present study solid sludge and effluent of both cardboard and handmade paper industries was collected for developing a mushroom cultivation technique to achieve zero waste discharges. Findings of present research work reveals that when 50% paper industries waste is used by mixing with 50% (w/w) wheat straw, significant increase (96.38%) in biological efficiency over control of wheat straw was observed. Further, cultivated basidiocarps showed normal morphology of stipe and pileus. Cross section of lamellae did not show any abnormality in the attachment of basidiospores, hymenal trama and basidium. No toxicity was found when fruiting bodies were tested chemically.

  1. Biodiversity, evolution and adaptation of cultivated crops.

    Science.gov (United States)

    Vigouroux, Yves; Barnaud, Adeline; Scarcelli, Nora; Thuillet, Anne-Céline

    2011-05-01

    The human diet depends on very few crops. Current diversity in these crops is the result of a long interaction between farmers and cultivated plants, and their environment. Man largely shaped crop biodiversity from the domestication period 12,000 B.P. to the development of improved varieties during the last century. We illustrate this process through a detailed analysis of the domestication and early diffusion of maize. In smallholder agricultural systems, farmers still have a major impact on crop diversity today. We review several examples of the major impact of man on current diversity. Finally, biodiversity is considered to be an asset for adaptation to current environmental changes. We describe the evolution of pearl millet in West Africa, where average rainfall has decreased over the last forty years. Diversity in cultivated varieties has certainly helped this crop to adapt to climate variation. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  2. Genetically modified plants: Decade of commercial cultivation

    Directory of Open Access Journals (Sweden)

    Mladenović-Drinić Snežana

    2005-01-01

    Full Text Available The year 2005 marks the beginning of the 10th consecutive year of commercial cultivation of genetically modified plants all around the world. The first GM variety of crops appeared on market during 1995 year and from that global area of biotech crops increased to 81 mil hectares in 2004. Genetically modified plant tolerant to herbicides, resistant to insects, improved quality have been developed. The use of GMO, their release into environment cultivation, utilization as food and feed is regulated in the EU by set of directives: 90/220, 2001/18, 2002/53, 1830/2003. Informer Yugoslavia the low about GMO was adopted in may 2001. That law consist of common regulation and it is in accordinance with EU regulation. Detection of genetic modification in seed and food could be done by PCR or ELISA methods.

  3. Resource-saving inter-row cultivator

    Directory of Open Access Journals (Sweden)

    N. E. Rudenko

    2017-01-01

    Full Text Available Inter-row cultivators have some shortcomings: design is complicated due to placing on each section of a 4-unit (parallelogram suspension of working tools; as the copying means use wheels which are mounted at distance from working tools, in other vertical plane, and have negative effect on variability of tillage depth; working tools are V-shaped hoes with a crumbling angle not more than 16 degrees. In the operation course the parts of a leg and a hoe, moving in the soil, raise it and throw to the side, creating not aligned surface grooves are formed, imposed moist soil. These processes are exacerbated by increasing the operating speed of the cultivator. The authors offered a resource-saving inter-row cultivator with a radial suspension of working tools. A flat plate spring was used as a beam. This simplifies the design, eliminates the horizontal oscillations of the working tools, provides a constant pressing them in the process. The working tool in the form of a flat lancet plowshares with a spiral fixed on the leg was designed. Operating width of a ploughshare is of 420 mm, thickness equals 4 (5 mm. The spiral with a diameter of 50 mm is made of a carbon spring wire with a diameter of 2-3 mm. One hoe is set instead of three-five tines on each section, that significantly reduces material consumption. A plough share with a spiral form the swinging-loosening element that provides creating a fine lumpy topsoil. The ploughshare performs the copying functions therefore the additional copying wheels are not required. Tests showed that the new working tool of a cultivator allows to operate qualitatively at a speed up to 14-18 km/h.

  4. Cultivation Of Deep Subsurface Microbial Communities

    Science.gov (United States)

    Obrzut, Natalia; Casar, Caitlin; Osburn, Magdalena R.

    2018-01-01

    The potential habitability of surface environments on other planets in our solar system is limited by exposure to extreme radiation and desiccation. In contrast, subsurface environments may offer protection from these stressors and are potential reservoirs for liquid water and energy that support microbial life (Michalski et al., 2013) and are thus of interest to the astrobiology community. The samples used in this project were extracted from the Deep Mine Microbial Observatory (DeMMO) in the former Homestake Mine at depths of 800 to 2000 feet underground (Osburn et al., 2014). Phylogenetic data from these sites indicates the lack of cultured representatives within the community. We used geochemical data to guide media design to cultivate and isolate organisms from the DeMMO communities. Media used for cultivation varied from heterotrophic with oxygen, nitrate or sulfate to autotrophic media with ammonia or ferrous iron. Environmental fluid was used as inoculum in batch cultivation and strains were isolated via serial transfers or dilution to extinction. These methods resulted in isolating aerobic heterotrophs, nitrate reducers, sulfate reducers, ammonia oxidizers, and ferric iron reducers. DNA sequencing of these strains is underway to confirm which species they belong to. This project is part of the NASA Astrobiology Institute Life Underground initiative to detect and characterize subsurface microbial life; by characterizing the intraterrestrials, the life living deep within Earth’s crust, we aim to understand the controls on how and where life survives in subsurface settings. Cultivation of terrestrial deep subsurface microbes will provide insight into the survival mechanisms of intraterrestrials guiding the search for these life forms on other planets.

  5. Soil protection through almond tree cultivation

    International Nuclear Information System (INIS)

    Garcia, C.; Hernandez, T.; Moreno, J. L.; Bastida, F.; Masciandaro, G.; Mennone, C.; Ceccanti, B.

    2009-01-01

    Most threat to soil are particularly severe in areas with steps slopes and suffering dry periods followed by heavy rain such as the Mediterranean regions. Severity is aggravated by lacking or inappropriate farming systems. Therefore the objective of this work was to demonstrate that land management based on cultivation of new varieties of local crops (almond trees) suited to these conditions may result in a sustainable system to prevent soil degradation. (Author)

  6. Morphology and rheology in filamentous cultivations.

    Science.gov (United States)

    Wucherpfennig, T; Kiep, K A; Driouch, H; Wittmann, C; Krull, R

    2010-01-01

    Because of their metabolic diversity, high production capacity, secretion efficiency, and capability of carrying out posttranslational modifications, filamentous fungi are widely exploited as efficient cell factories in the production of metabolites, bioactive substances, and native or heterologous proteins, respectively. There is, however, a complex relationship between the morphology of these microorganisms, transport phenomena, the viscosity of the cultivation broth, and related productivity. The morphological characteristics vary between freely dispersed mycelia and distinct pellets of aggregated biomass, every growth form having a distinct influence on broth rheology. Hence, the advantages and disadvantages for mycelial or pellet cultivation have to be balanced out carefully. Because of the still inadequate understanding of the morphogenesis of filamentous microorganisms, fungal morphology is often a bottleneck of productivity in industrial production. To obtain an optimized production process, it is of great importance to gain a better understanding of the molecular and cell biology of these microorganisms as well as the relevant approaches in biochemical engineering. In this chapter, morphology and growth of filamentous fungi are described, with special attention given to specific problems as they arise from fungal growth forms; growth and mass transfer in fungal biopellets are discussed as an example. To emphasize the importance of the flow behavior of filamentous cultivation broths, an introduction to rheology is also given, reviewing important rheological models and recent studies concerning rheological parameters. Furthermore, current knowledge on morphology and productivity in relation to the environom is outlined in the last section of this review. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Use of waste material in cultivation substrates

    Directory of Open Access Journals (Sweden)

    Petr Salaš

    2004-01-01

    Full Text Available Gardeners' practical experience and experimental work prove the affirmation that the used substrate is a very important base for the production of quality nursery products. It is important to emphasis the complexity and synergy of all factors influencing the ecosystem and there mutual relations. Physical, chemical and biological properties do not separately affect the growth and development of plants. In addition, the relations are not statical but differ in relation with other factors changes. This article is dealing with the possibility to use waste material from timber processing in cultivation substrates. The large scale use of such substrates would enable people to reach a relative independence from peat substrates, of which the global reserve is gradually decreasing.Our research activities focus on the use of bark. The basic problems of a bark substrate are easy dehydration and unbalanced nutrition of trees and shrubs. The suggested and experimented cultivation technology solves these problems. It is based on the cultivation of woody species in bark substrates, using modern irrigation systems, slow release fertilisers (Silvamix Forte and special soil conditioners (TerraCottem. This technology was tested on the following species of trees and shrubs: Malus and Buxus.

  8. Strawberry cultivation in Brazil | Cultivo de morangos no Brasil

    Directory of Open Access Journals (Sweden)

    José Machado

    2016-06-01

    Full Text Available The strawberry is cultivated in different regions of the world. Their cultivation have shown demand larger family hand labor and highly profitable.  The strawberry is a very old fruit. Wild species existed for more 50 million years, but the specie was tamed around the XIV century A.C.  There are various types of cultivation, among them stand out traditional cultivation and organic cultivation. The more important factors affecting the strawberries are climate, pests and diseases. Know the types of cultivation and strawberry it is important for decision making in the future, such as use of lichens in cultivation. The aim of this work is to explain about conventional and organic agriculture with emphasis in lichens on strawberry crop to support scientific research in more depth character.> S

  9. Uranium uptake by hydroponically cultivated crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dvorakova, Marcela [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.cz [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic)

    2011-06-15

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC{sub 50} value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC{sub 50} = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: > The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. > Uranium is mainly localized in the root system. > Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. > The phosphates deficiency increase the uranium uptake.

  10. Uranium uptake by hydroponically cultivated crop plants

    International Nuclear Information System (INIS)

    Soudek, Petr; Petrova, Sarka; Benesova, Dagmar; Dvorakova, Marcela; Vanek, Tomas

    2011-01-01

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC 50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC 50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: → The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. → Uranium is mainly localized in the root system. → Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. → The phosphates deficiency increase the uranium uptake.

  11. Radiocaesium - 137 in cultivated and woodland mushrooms

    International Nuclear Information System (INIS)

    Stankovic, S.; Stankovic, A.

    1997-01-01

    In the present work the results obtained for activity levels of 137 Cs in samples of cultivated mushrooms (Champignons - Agaricus Silvicola Vitt. Peck.) and woodland fruits ( Chantarelle - Cantarelus Cibarius Fr.; Bollets -Boletus Edulis. ex Fr. and Black Trumpets - Cratarelus Conucopioides) are presented. These samples were collected from 1991 to 1996. Biodiversity of the mushrooms regarding their uptake of radionuclides was found. Thus, the maximum value of 137 Cs activity was found in the sample of dry Bollets 375 Bq/kg in 1993. Moreover, the mean activity level of this species was much higher (126 + - 10 Bq/kg) in 1996. than, levels found in any samples taken from the same environment. (author)

  12. Microeconomic aspects of energy crops cultivation

    International Nuclear Information System (INIS)

    Bartolelli, V.; Mutinati, G.; Pisani, F.

    1992-01-01

    The topic of energy crops, namely of those crops designed to produce biomass to transform into ethanol, has been explored, in Italy and abroad, in all its technical and agronomical aspects. The microeconomic aspect, including the evaluation of convenience for the farmer in adopting such crops, is, on the contrary, less well researched. RENAGRI has developed a research methodology able to give information about the level of convenience of two energy crops (Sweet Sorghum and Topinambour) and has applied it to different Italian agricultural situations, in order to verify the existence of conditions favourable to the cultivation of the two crops, or to indicate the necessity of eventual subvention. (author)

  13. Cultivating nursing leadership for our envisioned future.

    Science.gov (United States)

    Galuska, Lee A

    2012-01-01

    Nurses have been called upon to lead and partner in the transformation of health care. Leadership is a component of the scope of nursing practice; however, the optimal approach to development of leadership competency has not been established. A metasynthesis of qualitative studies on leadership development was conducted to enhance an understanding of conditions that nurses reported to support or hinder their development as leaders. Noblit and Hare's approach was used for the metasynthesis process. Three overarching themes emerged. Opportunity structure, the relationship factor, and organizational culture are essential factors contributing to the successful cultivation of leadership competencies in nurses.

  14. Optimisation of cultivation parameters in photobioreactors for microalgae cultivation using the A-stat technique

    NARCIS (Netherlands)

    Barbosa, M.J.; Hoogakker, J.; Wijffels, R.H.

    2003-01-01

    Light availability inside the reactor is often the bottleneck in microalgal cultivation and for this reason much attention is being given to light limited growth kinetics of microalgae, aiming at the increase of productivity in photobioreactors. Steady-state culture characteristics are commonly used

  15. Comparison between cultivated and total bacterial communities associated with Cucurbita pepo using cultivation-dependent techniques and 454 pyrosequencing.

    Science.gov (United States)

    Eevers, N; Beckers, B; Op de Beeck, M; White, J C; Vangronsveld, J; Weyens, N

    2016-02-01

    Endophytic bacteria often have beneficial effects on their host plants that can be exploited for bioremediation applications but, according to the literature, only 0.001-1% of all endophytic microbes should be cultivable. This study compared the cultivated endophytic communities of the roots and shoots of Cucurbita pepo with the total endophytic communities as determined by cultivation-dependent techniques and 454 pyrosequencing. The ten most abundant taxa of the total communities aligned well with the cultivated taxa; however, the abundance of these taxa in the two communities differed greatly. Enterobacter showed very low presence in the total communities, whereas they were dominantly present in the cultivated communities. Although Rhizobium dominated in total root and shoot communities, it was poorly cultivable and even then only in growth media containing plant extract. Since endophytes likely contribute to plant-growth promotion, cultivated bacterial strains were tested for their plant-growth promoting capabilities, and the results were correlated with their abundance in the total community. Bacillus and Pseudomonas showed promising results when considering cultivability, abundance in the total community and plant-growth promoting capability. This study demonstrated that, although a limited number of bacterial genera were cultivable, current cultivation-dependent techniques may be sufficient for further isolation and inoculation experiments that aim to improve phytoremediation efficiency. Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. Photobioreactor cultivation strategies for microalgae and cyanobacteria.

    Science.gov (United States)

    Johnson, Tylor J; Katuwal, Sarmila; Anderson, Gary A; Gu, Liping; Zhou, Ruanbao; Gibbons, William R

    2018-03-08

    The current burden on fossil-derived chemicals and fuels combined with the rapidly increasing global population has led to a crucial need to develop renewable and sustainable sources of chemicals and biofuels. Photoautotrophic microorganisms, including cyanobacteria and microalgae, have garnered a great deal of attention for their capability to produce these chemicals from carbon dioxide, mineralized water, and solar energy. While there have been substantial amounts of research directed at scaling-up production from these microorganisms, several factors have proven difficult to overcome, including high costs associated with cultivation, photobioreactor construction, and artificial lighting. Decreasing these costs will substantially increase the economic feasibility of these production processes. Thus, the purpose of this review is to describe various photobioreactor designs, and then provide an overview on lighting systems, mixing, gas transfer, and the hydrodynamics of bubbles. These factors must be considered when the goal of a production process is economic feasibility. Targets for improving microalgae and cyanobacteria cultivation media, including water reduction strategies will also be described. As fossil fuel reserves continue to be depleted and the world population continues to increase, it is imperative that renewable chemical and biofuel production processes be developed toward becoming economically feasible. Thus, it is essential that future research is directed toward improving these processes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018. © 2018 American Institute of Chemical Engineers.

  17. Production of deuterated switchgrass by hydroponic cultivation.

    Science.gov (United States)

    Evans, Barbara R; Bali, Garima; Foston, Marcus; Ragauskas, Arthur J; O'Neill, Hugh M; Shah, Riddhi; McGaughey, Joseph; Reeves, David; Rempe, Caroline S; Davison, Brian H

    2015-07-01

    The bioenergy crop switchgrass was grown hydroponically from tiller cuttings in 50 % D 2 O to obtain biomass with 34 % deuterium substitution and physicochemical properties similar to those of H 2 O-grown switchgrass controls. Deuterium enrichment of biological materials can potentially enable expanded experimental use of small angle neutron scattering (SANS) to investigate molecular structural transitions of complex systems such as plant cell walls. Two key advances have been made that facilitate cultivation of switchgrass, an important forage and biofuel crop, for controlled isotopic enrichment: (1) perfusion system with individual chambers and (2) hydroponic growth from tiller cuttings. Plants were grown and maintained for several months with periodic harvest. Photosynthetic activity was monitored by measurement of CO2 in outflow from the growth chambers. Plant morphology and composition appeared normal compared to matched controls grown with H2O. Using this improved method, gram quantities of switchgrass leaves and stems were produced by continuous hydroponic cultivation using growth medium consisting of basal mineral salts in 50 % D2O. Deuterium incorporation was confirmed by detection of the O-D and C-D stretching peaks with FTIR and quantified by (1)H- and (2)H-NMR. This capability to produce deuterated lignocellulosic biomass under controlled conditions will enhance investigation of cell wall structure and its deconstruction by neutron scattering and NMR techniques.

  18. INTENSIFICATION OF JELLY MUSHROOM CULTIVATION IN PAKEM SLEMAN

    OpenAIRE

    Sulistiya; Retno Lantarsih; Titop Dwiwinarno*

    2015-01-01

    Mushroom cultivation is long enough to be a source of income for some people in Pakem, Sleman. However, cultivation techniques that do not yet meet the standards for technical, so that productivity is still low. Marketing mushrooms are limited to the traditional market. Waste mushroom has not been used well, so potentially to pollute the environment mushroom. This service activities include the provision of mushroom cultivation equipment, such as water pumps and termohygrome...

  19. Mushroom cultivation in Brazil: challenges and potential for growth

    OpenAIRE

    Dias,Eustáquio Souza

    2010-01-01

    Mushroom cultivation is rapidly expanding in Brazil because Brazilians have discovered the medicinal and culinary value of mushrooms and their economic situation has improved. However, the horticultural technology for cultivating mushrooms under Brazilian conditions is lacking. For many years, the mushroom cultivation technology used in Brazil was adapted from developed countries whose materials and climate were different from those of Brazil. In order to exploit the Brazilian potential for m...

  20. ECOLOGICAL FACTOR SCORE OF THE TOBACCO CULTIVATION ON THE ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Г. Архіпова

    2012-04-01

    Full Text Available The problem of the quality and safety of tobacco cultivation in Ukraine was described in the article. Asfar as the cultivation of this plant is accompanied by using of the pesticides and other hazardous chemicals,the problem requires the solution in the nearest future. The techniques of "organic" tobacco cultivation,which are used in other countries and can be adopted in Ukraine, have been considered

  1. Domestication of a Mesoamerican cultivated fruit tree, Spondias purpurea.

    Science.gov (United States)

    Miller, Allison; Schaal, Barbara

    2005-09-06

    Contemporary patterns of genetic variation in crops reflect historical processes associated with domestication, such as the geographic origin(s) of cultivated populations. Although significant progress has been made in identifying several global centers of domestication, few studies have addressed the issue of multiple origins of cultivated plant populations from different geographic regions within a domestication center. This study investigates the domestication history of jocote (Spondias purpurea), a Mesoamerican cultivated fruit tree. Sequences of the chloroplast spacer trnG-trnS were obtained for cultivated and wild S. purpurea trees, two sympatric taxa (Spondias mombin var. mombin and Spondias radlkoferi), and two outgroups (S. mombin var. globosa and Spondias testudinus). A phylogeographic approach was used and statistically significant associations of clades and geographical location were tested with a nested clade analysis. The sequences confirm that wild populations of S. purpurea are the likely progenitors of cultivated jocote trees. This study provides phylogeographic evidence of multiple domestications of this Mesoamerican cultivated fruit tree. Haplotypes detected in S. purpurea trees form two clusters, each of which includes alleles recovered in both cultivated and wild populations from distinct geographic regions. Cultivated S. purpurea populations have fewer unique trnG-trnS alleles than wild populations; however, five haplotypes were absent in the wild. The presence of unique alleles in cultivation may reflect contemporary extinction of the tropical dry forests of Mesoamerica. These data indicate that some agricultural habitats may be functioning as reservoirs of genetic variation in S. purpurea.

  2. Cultivation of native seaweed Gracilaria domingensis (Rhodophyta in Southern Brazil

    Directory of Open Access Journals (Sweden)

    José Pedrassoli Salles

    2010-06-01

    Full Text Available The aim of this work was to study the cultivation of Gracilaria domingensis in a mussel farming urbanized area in Santa Catarina, Brazil. Relative growth rate was the parameter used to evaluate the cuttings attachment methods on the cultivation rope, cuttings density, cultivation period and cystocarpic versus unfertile thalli performance. The cultivation was feasible only when protected by net cages due to herbivory. The tie-tie attachment method presented the best results. No differences were observed when comparing the cuttings densities and reproductive phase. Future studies should evaluate the cost-effectiveness of producing the species in net cages and its potential as biofilter.

  3. Synthesis of 2-deoxy-2,2-difluoro-α-maltosyl fluoride and its X-ray structure in complex with Streptomyces coelicolor GlgEI-V279S

    Energy Technology Data Exchange (ETDEWEB)

    Thanna, Sandeep; Lindenberger, Jared J.; Gaitonde, Vishwanath V.; Ronning, Donald R.; Sucheck, Steven J. (Toledo)

    2015-06-05

    Streptomyces coelicolor (Sco) GlgEI is a glycoside hydrolase involved in α-glucan biosynthesis and can be used as a model enzyme for structure-based inhibitor design targeting Mycobacterium tuberculosis (Mtb) GlgE. The latter is a genetically validated drug target for the development of anti-Tuberculosis (TB) treatments. Inhibition of Mtb GlgE results in a lethal buildup of the GlgE substrate maltose-1-phosphate (M1P). However, Mtb GlgE is difficult to crystallize and affords lower resolution X-ray structures. Sco GlgEI-V279S on the other hand crystallizes readily, produces high resolution X-ray data, and has active site topology identical to Mtb GlgE. We report the X-ray structure of Sco GlgEI-V279S in complex with 2-deoxy-2,2-difluoro-α-maltosyl fluoride (α-MTF, 5) at 2.3 Å resolution. α-MTF was designed as a non-hydrolysable mimic of M1P to probe the active site of GlgE1 prior to covalent bond formation without disruption of catalytic residues. The α-MTF complex revealed hydrogen bonding between Glu423 and the C1F which provides evidence that Glu423 functions as proton donor during catalysis. Further, hydrogen bonding between Arg392 and the axial C2 difluoromethylene moiety of α-MTF was observed suggesting that the C2 position tolerates substitution with hydrogen bond acceptors. The key step in the synthesis of α-MDF was transformation of peracetylated 2-fluoro-maltal 1 into peracetylated 2,2-difluoro-α-maltosyl fluoride 2 in a single step via the use of Selectfluor®

  4. The Cultivation of Wisdom in the Classroom

    Directory of Open Access Journals (Sweden)

    Juliane Reams

    2015-03-01

    Full Text Available This article focuses on a research project that was designed to inquire into the cultivation of wisdom in the classroom in the context of a newly implemented school subject called Glück (English: happiness. Glück was introduced in order to make a difference in traditional mainstream schooling as a reaction to school curricula that emphasize data and knowledge transfer. It is different and new because it embraces the kind of learning that includes the senses, the mind, body, spirit and the guts. Its multidimensional approach makes an attempt to validate a renunciation of the reductionistic perspective of traditional and contemporary schooling. How it is implemented served as a transformational process through a set of experiential exercises, group discussions, contemplative practices, teamwork etc. It is my aim to give an insight into what I understood as an alternative learning arena embedded in a traditional schooling system and the implications for further development beyond the transfer of data and information in adolescents. Zooming in on Glück, I aim to provide some perspectives on how key experiences and the reflection upon them can lead to the cultivation of wisdom. The understanding of cultivating wisdom I have gained from this study is that it is a dynamic process where the creation of new structures of meaning making emerge through the interaction with others, with oneself and the reflection upon one’s own interior processes that can help unfold, know how to use and refine tacit knowledge. Part of this process is actively discovering and transforming complex information in order to embody it and make it one’s own. Due to the assumption that traditional schooling mostly puts an emphasis on conveying informational knowledge (Hart, 2009; Sternberg, 2001 (to the more or less attentive students and another assumption that wisdom is often seen in connection to age, this article makes an attempt to give an alternative perspective. In

  5. Microalgae: cultivation techniques and wastewater phycoremediation.

    Science.gov (United States)

    Pacheco, Marcondes M; Hoeltz, Michele; Moraes, Maria S A; Schneider, Rosana C S

    2015-01-01

    Generation of liquid and gaseous effluents is associated with almost all anthropogenic activities. The discharge of these effluents into the environment without treatment has reduced the availability and quality of natural resources, representing a serious threat to the balance of different ecosystems and human health. Universal access to water and global warming are topics of intense concern and are listed as priorities in the vast majority of global scientific, social and political guidelines. Conventional techniques to treat liquid and gaseous effluents pose economic and/or environmental limitations that prevent their use in certain applications. The technique of phycoremediation, which uses microalgae, macroalgae, and cyanobacteria for the removal or biotransformation of pollutants, is an emerging technology that has been highlighted due to its economic viability and environmental sustainability. This literature review discusses different techniques of microalgae cultivation and their use in the phycoremediation of contaminants in wastewater.

  6. USE OF ARTIFICIAL LIGHT IN MUSHROOM CULTIVATION

    Directory of Open Access Journals (Sweden)

    N. L. Poyedinok

    2013-12-01

    Full Text Available Artificial light is used in greenhouses to increase productivity and quality of agricultural and ornamental plants. Despite the awareness of the fact that light also plays important role in the life of nonhotosynthetic organisms, such as fungi, its using in their biotechnology cultivation is currently limited. Science has quite a large amount information about the influence of artificial light of different nature on morphogenesis, metabolic processes and productivity of more than 100 species of fungi, many of which are valuable producers of biologically active compounds. Themechanisms of photoreactions of various fungi, which is an integral part of a purposeful photoregulation their activity in biotechnological processes are described. The analysis of the researches and of the experience of their practical application allows predicting potential of using artificial light in mushroom growing industry, as well as in creating highly productive, environmentally clean technologies of targeted synthesis of the final product.

  7. Lisianthus cultivation using differentiated light transmission nets

    Directory of Open Access Journals (Sweden)

    Paulo Hercilio Viegas Rodrigues

    2016-08-01

    Full Text Available The Lisianthus stands out as one of the ten most cut flowers sold in the world. The use of meshes in a different light transmission is gaining more space in horticulture with promising results in greenhouse. The aim of this study was to evaluate the development of lisianthus grown in different light transmission meshes in blue, black, red and control treatments, which were transplanted 20 seedlings to cultivate Snow white with three replications, and therefore, 60 plants 240 plants per treatment in total. Agronomic characteristics such as plant height and length of the top pair of leaves were evaluated at 15, 38, 59, 82 and 105 days after transplanting. Other features such as early flowering, thick stem, distance between us and weight of the harvested stems were obtained at harvest stage. At the end of the evaluations, the treatment of red net was the most consistent with a significant difference in stem height and earliness in flowering.

  8. Principals, Trust, and Cultivating Vibrant Schools

    Directory of Open Access Journals (Sweden)

    Megan Tschannen-Moran

    2015-03-01

    Full Text Available Although principals are ultimately held accountable to student learning in their buildings, the most consistent research results have suggested that their impact on student achievement is largely indirect. Leithwood, Patten, and Jantzi proposed four paths through which this indirect influence would flow, and the purpose of this special issue is to examine in greater depth these mediating variables. Among mediating variables, we assert that trust is key. In this paper, we explore the evidence that points to the role that faculty trust in the principal plays in student learning and how principals can cultivate trust by attending to the five facets of trust, as well as the correlates of trust that mediate student learning, including academic press, collective teacher efficacy, and teacher professionalism. We argue that trust plays a role in each of the four paths identified by Leithwood, Patten, and Jantzi. Finally, we explore possible new directions for future research.

  9. Cultivated Land Changes and Agricultural Potential Productivity in Mainland China

    Directory of Open Access Journals (Sweden)

    Linlin Xiao

    2015-08-01

    Full Text Available With rapid and continuous population growth and the associated declining quality of cultivated land, food security in China has been attracting the attention of scholars both domestically and internationally. In recent decades, the implications of the cultivated land balance policy have promoted spatial changes of cultivated land. Estimating the agricultural potential productivity and assessing its response to cultivated land changes could provide a scientific basis for strategic decision-making concerning grain production and thus guarantee food security. In the present study, the Agro-Ecological Zone (AEZ model was applied to estimate the agricultural potential productivity. Data from the second national land survey were first applied to characterize the changes of cultivated land (by comparing the cultivated land in 2009 with that in 2012 and their influence on potential productivity in Mainland China. We propose a utilization degree of total potential productivity (UTP and its ratio coefficient (RUTP to reveal the utilization status of potential productivity and its change characteristics at the provincial level. It was found that there was a trend for cultivated land to be shifted away from cities, and the average productive capability per hectare of cultivated land declined from 7386.5 kg/ha to 6955.2 kg/ha by occupying highly productive cultivated land generally near the cities and compensating less productive cultivated land in remote areas. UTPs and RUTPs indicate a significant difference in the utilization status of potential productivity among the 31 provinces of Mainland China. Grain production with the aim of sustainable development should be strategized according to the particular facts of each province. The methods we applied can mine the impacts of cultivated land changes on potential productivity and the utilization of potential productivity effectively.

  10. High-power LEDs for plant cultivation

    Science.gov (United States)

    Tamulaitis, Gintautas; Duchovskis, Pavelas; Bliznikas, Zenius; Breive, Kestutis; Ulinskaite, Raimonda; Brazaityte, Ausra; Novickovas, Algirdas; Zukauskas, Arturas; Shur, Michael S.

    2004-10-01

    We report on high-power solid-state lighting facility for cultivation of greenhouse vegetables and on the results of the study of control of photosynthetic activity and growth morphology of radish and lettuce imposed by variation of the spectral composition of illumination. Experimental lighting modules (useful area of 0.22 m2) were designed based on 4 types of high-power light-emitting diodes (LEDs) with emission peaked in red at the wavelengths of 660 nm and 640 nm (predominantly absorbed by chlorophyll a and b for photosynthesis, respectively), in blue at 455 nm (phototropic function), and in far-red at 735 nm (important for photomorphology). Morphological characteristics, chlorophyll and phytohormone concentrations in radish and lettuce grown in phytotron chambers under lighting with different spectral composition of the LED-based illuminator and under illumination by high pressure sodium lamps with an equivalent photosynthetic photon flux density were compared. A well-balanced solid-state lighting was found to enhance production of green mass and to ensure healthy morphogenesis of plants compared to those grown using conventional lighting. We observed that the plant morphology and concentrations of morphologically active phytohormones is strongly affected by the spectral composition of light in the red region. Commercial application of the LED-based illumination for large-scale plant cultivation is discussed. This technology is favorable from the point of view of energy consumption, controllable growth, and food safety but is hindered by high cost of the LEDs. Large scale manufacturing of high-power red AlInGaP-based LEDs emitting at 650 nm and a further decrease of the photon price for the LEDs emitting in the vicinity of the absorption peak of chlorophylls have to be achieved to promote horticulture applications.

  11. Molecular Characterization of Cultivated Pawpaw (Asimina triloba) Using RAPD Markers

    Science.gov (United States)

    Hongwen Huang; Desmond R. Layne; Thomas L. Kubisiak

    2003-01-01

    Thirty-four extant pawpaw [Asimina triloba (L.) Dunal] cultivars and advanced selections representing a large portion of the gene pool of cultivated pawpaws were investigated using 71 randomly amplified polymorphic DNA (RAPD) markers to establish genetic identities and evaluate genetic relatedness. All 34 cultivated pawpaws were uniquely...

  12. The complemental role of dryland cultivated pastures in market ...

    African Journals Online (AJOL)

    The complemental role of dryland cultivated pastures in market-related beef production from semi-arid rangeland. ... Abstract. Rangeland condition is a decisive factor in determining the income/cost ratio of production hence in the profitability of any beef production enterprise. Cultivated pastures can play an important role in ...

  13. Psychological Processes Underlying Cultivation Effects: Further Tests of Construct Accessibility.

    Science.gov (United States)

    Shrum, L. J.

    1996-01-01

    Describes a study that tested whether the accessibility of information in memory mediates the cultivation effect (the effect of television viewing on social perceptions), consistent with the availability heuristic. Shows that heavy viewers gave higher frequency estimates (cultivation effect) and responded faster (accessibility effect) than did…

  14. Socio-Economic Determinants of Wetland Cultivation in Kemise ...

    African Journals Online (AJOL)

    A study of wetland use in Kemise, central Illubabor, southwestern Ethiopia, shows food shortage as the main factor behind wetland cultivation in the locality. However, discriminant analysis results indicate that it is the wealthier farmers who tend to cultivate wetlands rather than the economically less fortunate ones.

  15. Cultivating Discontinuity: Pentecostal Pedagogies of Yielding and Control

    Science.gov (United States)

    Brahinsky, Josh

    2013-01-01

    Exploring missionary study at an Assemblies of God Bible college through ethnography and training manuals demonstrates systematic pedagogies that cultivate sensory capabilities encouraging yielding, opening to rupture, and constraint. Ritual theory and the Anthropology of Christianity shift analytic scales to include "cultivation," a…

  16. Research Note Effects of previous cultivation on regeneration of ...

    African Journals Online (AJOL)

    We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...

  17. Agent-based modelling of shifting cultivation field patterns, Vietnam

    DEFF Research Database (Denmark)

    Jepsen, Martin Rudbeck; Leisz, S.; Rasmussen, K.

    2006-01-01

    Shifting cultivation in the Nghe An Province of Vietnam's Northern Mountain Region produces a characteristic land-cover pattern of small and larger fields. The pattern is the result of farmers cultivating either individually or in spatially clustered groups. Using spatially explicit agent...

  18. Cultivation of oyster mushroom ( Pleurotus spp.) on palm oil ...

    African Journals Online (AJOL)

    Oyster mushroom is a popular mushroom due to its nutritional, medicinal and potential commercial value. In Malaysia, the fungus is currently cultivated on sawdust and rice husk. In this study, the efficiency of cultivating oyster mushroom was assessed using palm oil mesocarp fibre as a substrate. The experiment consisted ...

  19. Moral Self-Cultivation East and West: A Critique

    Science.gov (United States)

    Slote, Michael

    2016-01-01

    Moral Self-Cultivation plays an important, even a central role, in the Confucian philosophical tradition, but philosophers in the West, most notably Aristotle and Kant, also hold that moral self-cultivation or self-shaping is possible and morally imperative. This paper argues that these traditions are psychologically unrealistic in what they say…

  20. Compound serum and hemin free medium for cultivation of ...

    African Journals Online (AJOL)

    Serum free cultivation of Leishmania is cost-effective and improves large scale production of well defined parasite material. Moreover, the production of recombinant pharmaceutical proteins requires cultivation of the host in a culture medium free of animal materials, so several culture media for Leishmania tarentolae ...

  1. Agronomic performance of five banana cultivars under protected cultivation

    Science.gov (United States)

    Banana has been grown both in open-field and protected cultivation in Turkey. So far protected cultivation is very popular due to the high yield and quality. The objective of the study was to evaluate agronomic performance of five new banana cultivars under plastic greenhouse. ‘MA 13’, ‘Williams’, ‘...

  2. Processes and Causes of Accelerated Soil Erosion on Cultivated ...

    African Journals Online (AJOL)

    Processes and Causes of Accelerated Soil Erosion on Cultivated Fields of South Welo, Ethiopia. ... In most of the highlands, crop cultivation is carried out without any type of terracing, while about 74 per cent of this land requires application of contour plowing, broad-based terracing, or bench terracing. The third group of ...

  3. Health Impacts of Tobacco Cultivation in Bangladesh | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... health problems among men, women, and children in Bangladesh will examine the health and socio-economic impact of tobacco cultivation. To date, the health hazards of growing tobacco have not been documented or well researched, particularly in low-and middle-income countries with high rates of tobacco cultivation.

  4. Effect of organic cultivation of rooibos tea plants ( Aspalathus linearis )

    African Journals Online (AJOL)

    The shoots of rooibos (Aspalathus linearis (Burm.f.) R.Dahlgren) plants, cultivated organically by small-scale farmers in Nieuwoudtville, are harvested for the production of tea. These practices could lead to decreasing soil fertility. It was hypothesised that soil from cultivated rooibos plots will have lower nutrient ...

  5. Economic benefit analysis of cultivating Pleurotus ostreatus with rape straw

    Science.gov (United States)

    Guan, Qinlan; Gong, Mingfu; Tang, Mei

    2018-04-01

    The cultivation of Pleurotus ostreatus with rape straw not only can save the cultivation cost of P. ostreatus, but also can reuse the resources and protect the environment. By adding different proportion of rape straw to the cultivation material of P. ostreatus, the reasonable amount of rape straw was selected and the economic benefit of P. ostreatus cultivated with the optimum amount of rape straw was analyzed. The results showed that adding 10% to 40% rape straw to the cultivation material of P. ostreatus did not affect the yield and biological conversion rate of P. ostreatus, and the ratio of production and investment of the amount of rape straw in the range of 10% to 50% was higher than of cottonseed husk alone as the main material of the formula.

  6. Aeration strategy for biofilm cultivation of the microalga Scenedesmus dimorphus.

    Science.gov (United States)

    Ji, Chunli; Wang, Junfeng; Liu, Tianzhong

    2015-10-01

    Biofilm cultivation of microalgae may be useful for biofuel production. However, many aspects for this cultivation method have not been well assessed. Accordingly, aeration strategy for biofilm cultivation of Scenedesmus dimorphus has been explored. Biomass, lipid and triacylglycerol (TAG) productivity in increased S. dimorphus as the CO2 concentration increased within 0.038-0.5% and kept constant with further increases. The biomass, lipid and TAG productivity increased with the speed increasing and an obvious threshold point was observed at 6.6 ml(-2) min(-1). The lipid and TAG content was unaffected by the aeration rate. Both the CO2 concentration as well as aeration speed affected the growth of S. dimorphus in biofilm cultivation. The optimized aeration strategy for biofilm cultivation was continuous air flow enriched with 1% CO2 (v/v) at 6.6 ml(-2) min(-1).

  7. The Cultivation of Cultural Awareness in English Teaching

    Institute of Scientific and Technical Information of China (English)

    王宁

    2015-01-01

    As the development of the information age,the cultivation of intercultural communicative competence has been extremely important. Thus foreign language teaching lays stress on the cultivation of language comprehensive application ability. Culture awareness is an important part of language comprehensive application ability. The cultivating of students’ cultural awareness is beneficial to improve their humanistic quality,broaden their international view,strengthen their patriotism spirit and sense of national mission,and achieve their all-round development. The paper will discuss the current situation of cultural awareness cultivation in English teaching. In view of the problems and its causes existing in the cultural awareness cultivation,three count measures have been proposed.

  8. A study on the comparison of antioxidant effects among cultivated ginseng, and cultivated wild ginseng extracts -Using the measurement of superoxide and hydroxy radical scavenging activities-

    Directory of Open Access Journals (Sweden)

    Tae Jin, Rhim

    2009-06-01

    Full Text Available Objectives : The objective of this study was to compare the antioxidant effects among cultivated wild ginseng and ginseng extracts. Methods : In vitro antioxidant activities were examined by superoxide and hydroxyl radical scavenging activities of ginseng and cultivated wild ginseng extracts. Results : 1. In the superoxide radical scavenging activities of ginseng and cultivated wild ginseng extracts, antioxidant activities of cultivated wild ginseng extracts was showed higher than cultivated ginseng in the concentration of 0.25 and 0.50㎎/㎖. 2. In the hydroxyl radical scavenging activities of ginseng and cultivated wild ginseng extracts, antioxidant activities of cultivated wild ginseng extracts was showed higher than cultivated ginseng in the concentration of 1.0, 2.5, and 5.0㎎/㎖. Conclusions : In summary, the results of this study demonstrate that cultivated wild ginseng extracts had higher antioxidant activities to cultivated ginseng.

  9. A study on the comparison of antioxidant effects among wild ginseng, cultivated wild ginseng, and cultivated ginseng extracts

    Directory of Open Access Journals (Sweden)

    Hae Young, Jang

    2008-09-01

    Full Text Available Objective : The objective of this study was to compare the antioxidant effects among wild ginseng, cultivated wild ginseng, and ginseng extracts. Methods : In vitro antioxidant activities were examined by total antioxidant capacity (TAC, oxygen radical scavenging capacity(ORAC, total phenolic content, 1, 1-Diphenyl-2-picrylhydrazyl (DPPH radical scavenging activity, inhibition of induced lipid peroxidation using liver mitochondria, reactive oxygen species(ROS scavenging effect using 2’, 7’-dichlorofluorescein(DCF fluorescence. Results : 1. TAC of 1.5 and 3.75 mg extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 2. ORAC of 2, 10, and 20 μg extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 3. Total phenolic content of 0.375, 0.938, and 1.875 mg extracts was highest in cultivated wild ginseng, followed by wild ginseng and lowest in ginseng. 4. DPPH(1, 1 -Diphenyl-2-picrylhydrazyl scavenging activity between wild ginseng and cultivated wild ginseng did not differ significantly (p>0.05. 5. Induced lipid peroxidation, measured by TBARS concentration in solution containing rat liver mitochondria incubated in the presence of FeSO4/ascorbic acid was inhibited as amounts of wild ginseng, cultivated wild ginseng, and ginseng extracts increased. TBARS concentration of ginseng extracts were significantly (p<0.05 higher than wild ginseng or cultivated wild ginseng extracts. 6. DCF fluorescence intensity was decreased as concentrations of wild ginseng, cultivated wild ginseng, and ginseng extracts increased, demonstrating that ROS generation was inhibited in a concentrationdependent manner. Conclusions : In summary, the results of this study demonstrate that cultivated wild ginseng extracts had similar antioxidant activities to wild ginseng extracts and greater that of cultivated ginseng extracts.

  10. Technical evaluation of photobioreactors for microalgae cultivation

    Directory of Open Access Journals (Sweden)

    Płaczek Małgorzata

    2017-01-01

    Full Text Available This paper undertakes the description and assessment of various solutions applied for the design of photobioreactors as the type of apparatus, which can provide high output of green algae biomass. The design of such apparatus plays an important role in the context of the concurrent fulfillment of ecological and economic requirements, which are necessary to conduct an efficient and effective technology using cheap and easily accessible resources to produce different goods. Nowadays, algae is seen as one of the most promising sustainable way to produce energy in the future (biofuels, electricity, thermal energy but technologies of biomass production and processing are still under development particularly to increase biomass and energy output. The cultivation costs in closed systems are still high, limiting their commercial applications to high-valued compounds but they can be reduced by efficient bioreactor designs, which are able to achieve high areal biomass productivities. This paper focuses on the advantages and drawbacks associated with the application of the particular types of bioreactors in algae production, description of their operation parameters and area for practical application, pointing of the constructions (tubular, flat panel, bubble column that can contribute to improvement the profitability of large-scale production.

  11. Advanced continuous cultivation methods for systems microbiology.

    Science.gov (United States)

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories.

  12. The organic fertilization in the onion cultivation

    Directory of Open Access Journals (Sweden)

    Roberto Llorente Villa

    2016-02-01

    Full Text Available The present work was developed in the UBPC “The Coast”, belonging to the Miscellaneous Crops Enterprise of Campechuela municipality, Granma province, during the period from November to March of the year 2010 – 2011. It was carried out in a reddish brown fersialitic soil, according with the new genetic classification of the soils of Cuba MINAGRI, (2000, with the objective of studying and evaluating the influence of different organic fertilizers in the growth, development and yield in the cultivation of onion, variety Texas Early Grain. For this reason it was necessary to work on blocks with 4 treatments and 4 replies. The treatments applied were: treatment 1 (vermicompost, treatment 2 (cow dung, treatment 3 (cachaça and treatment 4 (control, those were applied in a solid way. The growth variables that were evaluated were number of leaves, height of the plant, equatorial diameter, polar diameter and fresh weight of the bulb. The yield was also evaluated in t.ha-1 per treatment. High yields are achieved with the application of organic fertilizer, among 27 and 30 t.ha-1, this is an alternative for the sustainable production of this product which is highly demanded by the population.

  13. Cultivating gratitude and giving through experiential consumption.

    Science.gov (United States)

    Walker, Jesse; Kumar, Amit; Gilovich, Thomas

    2016-12-01

    Gratitude promotes well-being and prompts prosocial behavior. Here, we examine a novel way to cultivate this beneficial emotion. We demonstrate that 2 different types of consumption-material consumption (buying for the sake of having) and experiential consumption (buying for the sake of doing)-differentially foster gratitude and giving. In 6 studies we show that reflecting on experiential purchases (e.g., travel, meals out, tickets to events) inspires more gratitude than reflecting on material purchases (e.g., clothing, jewelry, furniture), and that thinking about experiences leads to more subsequent altruistic behavior than thinking about possessions. In Studies 1-2b, we use within-subject and between-subjects designs to test our main hypothesis: that people are more grateful for what they've done than what they have. Study 3 finds evidence for this effect in the real-world setting of online customer reviews: Consumers are more likely to spontaneously mention feeling grateful for experiences they have bought than for material goods they have bought. In our final 2 studies, we show that experiential consumption also makes people more likely to be generous to others. Participants who contemplated a significant experiential purchase behaved more generously toward anonymous others in an economic game than those who contemplated a significant material purchase. It thus appears that shifting spending toward experiential consumption can improve people's everyday lives as well as the lives of those around them. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. Technical evaluation of photobioreactors for microalgae cultivation

    Science.gov (United States)

    Płaczek, Małgorzata; Patyna, Agnieszka; Witczak, Stanisław

    2017-10-01

    This paper undertakes the description and assessment of various solutions applied for the design of photobioreactors as the type of apparatus, which can provide high output of green algae biomass. The design of such apparatus plays an important role in the context of the concurrent fulfillment of ecological and economic requirements, which are necessary to conduct an efficient and effective technology using cheap and easily accessible resources to produce different goods. Nowadays, algae is seen as one of the most promising sustainable way to produce energy in the future (biofuels, electricity, thermal energy) but technologies of biomass production and processing are still under development particularly to increase biomass and energy output. The cultivation costs in closed systems are still high, limiting their commercial applications to high-valued compounds but they can be reduced by efficient bioreactor designs, which are able to achieve high areal biomass productivities. This paper focuses on the advantages and drawbacks associated with the application of the particular types of bioreactors in algae production, description of their operation parameters and area for practical application, pointing of the constructions (tubular, flat panel, bubble column) that can contribute to improvement the profitability of large-scale production.

  15. Maize Endophytic Bacterial Diversity as Affected by Soil Cultivation History.

    Science.gov (United States)

    Correa-Galeote, David; Bedmar, Eulogio J; Arone, Gregorio J

    2018-01-01

    The bacterial endophytic communities residing within roots of maize ( Zea mays L.) plants cultivated by a sustainable management in soils from the Quechua maize belt (Peruvian Andes) were examined using tags pyrosequencing spanning the V4 and V5 hypervariable regions of the 16S rRNA. Across four replicate libraries, two corresponding to sequences of endophytic bacteria from long time maize-cultivated soils and the other two obtained from fallow soils, 793 bacterial sequences were found that grouped into 188 bacterial operational taxonomic units (OTUs, 97% genetic similarity). The numbers of OTUs in the libraries from the maize-cultivated soils were significantly higher than those found in the libraries from fallow soils. A mean of 30 genera were found in the fallow soil libraries and 47 were in those from the maize-cultivated soils. Both alpha and beta diversity indexes showed clear differences between bacterial endophytic populations from plants with different soil cultivation history and that the soils cultivated for long time requires a higher diversity of endophytes. The number of sequences corresponding to main genera Sphingomonas, Herbaspirillum, Bradyrhizobium and Methylophilus in the maize-cultivated libraries were statistically more abundant than those from the fallow soils. Sequences of genera Dyella and Sreptococcus were significantly more abundant in the libraries from the fallow soils. Relative abundance of genera Burkholderia, candidatus Glomeribacter, Staphylococcus, Variovorax, Bacillus and Chitinophaga were similar among libraries. A canonical correspondence analysis of the relative abundance of the main genera showed that the four libraries distributed in two clearly separated groups. Our results suggest that cultivation history is an important driver of endophytic colonization of maize and that after a long time of cultivation of the soil the maize plants need to increase the richness of the bacterial endophytes communities.

  16. Changes in shifting cultivation systems on small Pacific islands

    DEFF Research Database (Denmark)

    Mertz, Ole; Birch-Thomsen, Torben; Elberling, Bo

    2012-01-01

    The limited information on change in shifting cultivation systems of small islands of the Pacific stands in contrast to increasing evidence of this farming system's demise in other parts of the tropics. Here, we assess changes in agricultural activities during the past 40 years of Bellona Island......, Solomon Islands, where shifting cultivation is still maintained in the traditional way. Fallow length has increased despite population growth due to redistribution of the cultivated area, migration-induced extensification and changes in crops. Productivity of the farming system remains high although...

  17. Heterotrophic cultivation of microalgae for production of biodiesel.

    Science.gov (United States)

    Mohamed, Mohd Shamzi; Wei, Lai Zee; Ariff, Arbakariya B

    2011-08-01

    High cell density cultivation of microalgae via heterotrophic growth mechanism could effectively address the issues of low productivity and operational constraints presently affecting the solar driven biodiesel production. This paper reviews the progress made so far in the development of commercial-scale heterotrophic microalgae cultivation processes. The review also discusses on patentable concepts and innovations disclosed in the past four years with regards to new approaches to microalgal cultivation technique, improvisation on the process flow designs to economically produced biodiesel and genetic manipulation to confer desirable traits leading to much valued high lipid-bearing microalgae strains.

  18. Phylogeography of the wild and cultivated stimulant plant qat (Catha edulis, Celastraceae) in areas of historical cultivation.

    Science.gov (United States)

    Tembrock, Luke R; Simmons, Mark P; Richards, Christopher M; Reeves, Patrick A; Reilley, Ann; Curto, Manuel A; Meimberg, Harald; Ngugi, Grace; Demissew, Sebsebe; Al Khulaidi, Abdul Wali; Al-Thobhani, Mansoor; Simpson, Sheron; Varisco, Daniel M

    2017-04-01

    Qat ( Catha edulis , Celastraceae) is a woody plant species cultivated for its stimulant alkaloids. Qat is important to the economy and culture in large regions of Ethiopia, Kenya, and Yemen. Despite the importance of this species, the wild origins and dispersal of cultivars have only been described in often contradictory historical documents. We examined the wild origins, human-mediated dispersal, and genetic divergence of cultivated qat compared to wild qat. We sampled 17 SSR markers and 1561 wild and cultivated individuals across the historical areas of qat cultivation. On the basis of genetic structure inferred using Bayesian and nonparametric methods, two centers of origin in Kenya and one in Ethiopia were found for cultivated qat. The centers of origin in Ethiopia and northeast of Mt. Kenya are the primary sources of cultivated qat genotypes. Qat cultivated in Yemen is derived from Ethiopian genotypes rather than Yemeni wild populations. Cultivated qat with a wild Kenyan origin has not spread to Ethiopia or Yemen, whereas a small minority of qat cultivated in Kenya originated in Ethiopia. Hybrid genotypes with both Ethiopian and Kenyan parentage are present in northern Kenya. Ethiopian cultivars have diverged from their wild relatives, whereas Kenyan qat has diverged less. This pattern of divergence could be caused by the extinction of the wild-source qat populations in Ethiopia due to deforestation, undersampling, and/or artificial selection for agronomically important traits. © 2017 Tembrock et al. Published by the Botanical Society of America. This work is licensed under a Creative Commons public domain license (CC0 1.0).

  19. Dissolved triazines in watersheds under sugarcane cultivation

    Science.gov (United States)

    Portocarrero, Rocio; Aparicio, Virginia; De Gerónimo, Eduardo; Costa, José Luis

    2017-04-01

    Sugarcane is an important extensive crop in north western of Argentina. Chemical weed control have been increasing over the last years. The typical period of this practice takes place from October to December, at beginnig of rainy season. Atrazine and ametryn are the main herbicides used, they have moderate to high potential mobility in soils, which is a potential source of contamination for nearby streams. The aim of this study was to quantify both atrazine and ametryn contamination levels in two streams of the southeast of Tucuman (Argentina) under sugarcane production. This area has a subtropical climate, and a monsoon rainfall regime with an annual average of 700 mm. Five sampling points of Mista and Saladillo streams were monitored from September to April, during three growing season. In each growing season, four sampling moments were defined: M1) Before the herbicides application; M2) Beginning of the rainy season and during the chemical weed control period; M3) High accumulated rainfall; M4) End of the rainy season. Water samples were taken and stored in polypropylene bottles at -20°C until analysis. Samples were analyzed by ultra performance liquid chromatography (Waters® ACQUITY® UPLC) coupled to a mass spectrometer (MS/MS Quattro Premier XE Waters). Atrazine was quantified in all samples and the highest concentrations were found in M2 (0.03-3.07 μg L-1). For the others sampling moments, atrazine concentrations were ranged from 0.003 to 0.2 μg L-1. Ametryn was detected in the 90% of the samples. Ametryn concentrations in M2 varied from 0.004 to 0.32 μg L-1, and in the rest sampling moments were less than 0.11 μg L-1. Both herbicides were highly detected in the study area. Although atrazine is authorized for other crops in the area, ametryn is only authorized for sugarcane, the largest cultivation in the area.

  20. Dynamic control of gene expression in Saccharomyces cerevisiae engineered for the production of plant sesquitepene α-santalene in a fed-batch mode

    DEFF Research Database (Denmark)

    Scalcinati, Gionata; Knuf, Christoph; Partow, Siavash

    2012-01-01

    -santalene, the precursor of a commercially interesting compound, was constructed through a rationally designed metabolic engineering approach. Optimal sesquiterpene production was obtained by modulating the expression of one of the key metabolic steps of the mevalonate (MVA) pathway, squalene synthase (Erg9). To couple......Microbial cells engineered for efficient production of plant sesquiterpenes may allow for sustainable and scalable production of these compounds that can be used as e.g. perfumes and pharmaceuticals. Here, for the first time a Saccharomyces cerevisiae strain capable of producing high levels of α...... ERG9 expression to glucose concentration its promoter was replaced by the HXT1 promoter. In a second approach, the HXT2 promoter was used to express an ERG9 antisense construct. Using the HXT1 promoter to control ERG9 expression, it was possible to divert the carbon flux from sterol synthesis towards...

  1. Lactic acid production from lime-treated wheat straw by Bacillus coagulans: neutralization of acid by fed-batch addition of alkaline substrate

    NARCIS (Netherlands)

    Maas, R.H.W.; Bakker, R.R.; Jansen, M.L.A.; Visser, D.; Jong, de E.; Eggink, G.; Weusthuis, R.A.

    2008-01-01

    Conventional processes for lignocellulose-to-organic acid conversion requires pretreatment, enzymatic hydrolysis, and microbial fermentation. In this study, lime-treated wheat straw was hydrolyzed and fermented simultaneously to lactic acid by an enzyme preparation and Bacillus coagulans DSM 2314.

  2. Design of neural network model-based controller in a fed-batch microbial electrolysis cell reactor for bio-hydrogen gas production

    Science.gov (United States)

    Azwar; Hussain, M. A.; Abdul-Wahab, A. K.; Zanil, M. F.; Mukhlishien

    2018-03-01

    One of major challenge in bio-hydrogen production process by using MEC process is nonlinear and highly complex system. This is mainly due to the presence of microbial interactions and highly complex phenomena in the system. Its complexity makes MEC system difficult to operate and control under optimal conditions. Thus, precise control is required for the MEC reactor, so that the amount of current required to produce hydrogen gas can be controlled according to the composition of the substrate in the reactor. In this work, two schemes for controlling the current and voltage of MEC were evaluated. The controllers evaluated are PID and Inverse neural network (NN) controller. The comparative study has been carried out under optimal condition for the production of bio-hydrogen gas wherein the controller output is based on the correlation of optimal current and voltage to the MEC. Various simulation tests involving multiple set-point changes and disturbances rejection have been evaluated and the performances of both controllers are discussed. The neural network-based controller results in fast response time and less overshoots while the offset effects are minimal. In conclusion, the Inverse neural network (NN)-based controllers provide better control performance for the MEC system compared to the PID controller.

  3. 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.

  4. Recovery of resources for advanced life support space applications: effect of retention time on biodegradation of two crop residues in a fed-batch, continuous stirred tank reactor

    Science.gov (United States)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.; Cook, K.; Garland, J. L.

    2002-01-01

    Bioreactor retention time is a key process variable that will influence costs that are relevant to long distance space travel or long duration space habitation. However. little is known about the effects of this parameter on the microbiological treatment options that are being proposed for Advanced Life Support (ALS) systems. Two bioreactor studies were designed to examine this variable. In the first one, six retention times ranging from 1.3 to 21.3 days--were run in duplicate, 81 working-volume continuous stirred tank reactors (CSTR) that were fed ALS wheat residues. Ash-free dry weight loss, carbon mineralization, soluble TOC reduction, changes in fiber content (cellulose, hemicellulose, and lignin), bacterial numbers, and mineral recoveries were monitored. At short retention times--1.33 days--biodegradation was poor (total: 16-20%, cellulose - 12%, hemicellulose - 28%) but soluble TOC was decreased by 75-80% and recovery of major crop inorganic nutrients was adequate, except for phosphorus. A high proportion of the total bacteria (ca. 83%) was actively respiring. At the longest retention time tested, 21.3 days, biodegradation was good (total: 55-60%, cellulose ca. 70%, hemicellulose - ca. 55%) and soluble TOC was decreased by 80%. Recovery of major nutrients, except phosphorus, remained adequate. A very low proportion of total bacteria was actively respiring (ca. 16%). The second bioreactor study used potato residue to determine if even shorter retention times could be used (range 0.25-2.0 days). Although overall biodegradation deteriorated, the degradation of soluble TOC continued to be ca. 75%. We conclude that if the goal of ALS bioprocessing is maximal degradation of crop residues, including cellulose, then retention times of 10 days or longer will be needed. If the goal is to provide inorganic nutrients with the smallest volume/weight bioreactor possible, then a retention time of 1 day (or less) is sufficient.

  5. Cultivation of three types of indigenous wild edible mushrooms ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-12-17

    Dec 17, 2008 ... effects related to their disposal (Mshandete et al., 2008). Cultivation of mushroom can .... The holes facilitated drainage, aeration (free diffusion of gases and .... sium, iron, copper, manganese, zinc and cobalt) were determined.

  6. Cultivating Peace: Conflict and Collaboration in Natural Resource ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cultivating Peace presents original case studies from Africa, Asia, and Latin America, ... experience on moving from conflict to collaborative modes of management. ... public health, and health systems research relevant to the emerging crisis.

  7. The Edibility and Cultivation of the Oyster Mushroom.

    Science.gov (United States)

    Brenneman, James; Guttman, Mark C.

    1994-01-01

    Describes an enjoyable and fascinating experience that involves the cultivation of oyster mushrooms. By allowing students to participate in this process, the students are able to better understand the biology and utility of fungi. (ZWH)

  8. Cultivation of Pleurotus ostreatus and other edible mushrooms.

    Science.gov (United States)

    Sánchez, Carmen

    2010-02-01

    Pleurotus ostreatus is the second most cultivated edible mushroom worldwide after Agaricus bisporus. It has economic and ecological values and medicinal properties. Mushroom culture has moved toward diversification with the production of other mushrooms. Edible mushrooms are able to colonize and degrade a large variety of lignocellulosic substrates and other wastes which are produced primarily through the activities of the agricultural, forest, and food-processing industries. Particularly, P. ostreatus requires a shorter growth time in comparison to other edible mushrooms. The substrate used for their cultivation does not require sterilization, only pasteurization, which is less expensive. Growing oyster mushrooms convert a high percentage of the substrate to fruiting bodies, increasing profitability. P. ostreatus demands few environmental controls, and their fruiting bodies are not often attacked by diseases and pests, and they can be cultivated in a simple and cheap way. All this makes P. ostreatus cultivation an excellent alternative for production of mushrooms when compared to other mushrooms.

  9. The Problems Detected in Mushroom Cultivation in Ankara

    Directory of Open Access Journals (Sweden)

    Mürüvvet Ulusoy Deniz

    2016-03-01

    Full Text Available Development of the cultivated mushroom farming which began to be produced in the 1960s in Turkey, has been more faster in the Mediterranean region than other regions. The development of mushroom cultivation has began to seen Marmara and İç Anadolu regions in recent years. The mushroom production which is very important for human health and nutrition, has been changing year to year (sometimes increase, sometimes decrease in the province of Ankara. The first private mushrrom cultivation company had been established in1963. Up to date, the number of private enterprises has changed over the years in Ankara. This study was carried out by doing a survey with an active 12 enterprises which the annual production capacity of 10-600 ton. The enterprises were visited and problems were determined during the cultivation. As a result of the study, It was observed that there are problems in production and marketing phases and with surface soil material

  10. Cultivation of live food organisms - status and scope in India

    Digital Repository Service at National Institute of Oceanography (India)

    Sumitra-Vijayaraghavan

    In the hatchery production of cultivable shell-fishes and fin-fishes, a reliable and continuous supply of live food of appropriate size is of importance. The organisms cultured as live feed presently in India are the microalgae, turbellarians...

  11. Mini Review: Innovation technology cultivation of durio in East Kalimantan

    Directory of Open Access Journals (Sweden)

    AFRILIA TRI WIDYAWATI

    2017-03-01

    Full Text Available Abstract. Widyawati AT, Nurbani. 2017. . Pros Sem Nas Masy Biodiv Indon 3: 132-137. Durian is native of the region where the climate is tropical wet, especially in Indonesia, Malaysia and Thailand. Durian plant species most widely known and cultivated in Indonesia is Durio zibethinus Murr. Improve the quality of fruit production in sufficient quantity to do with the increase in population as well as increasing fruit crop cultivation technology do. In addition to ensuring that products are safe to eat fruit cultivation technology needs to be done in an environmentally responsible in accordance with the SOP (Standard Operating Procedure and the concept of cultivation of GAP (Good Agriculture Practice.

  12. Carbon And Nitrogen Requirements For The Cultivation Of Oyster ...

    African Journals Online (AJOL)

    Carbon And Nitrogen Requirements For The Cultivation Of Oyster Mushroom ... It was found that under these experimental conditions, the carbon compounds supported growth except ribose, starch and dextrin. ... HOW TO USE AJOL.

  13. Macronutrient composition of three cucurbit species cultivated for ...

    African Journals Online (AJOL)

    .) Matsum. & Nakai., Cucumeropsis mannii Naudin, and Cucumis melo var. agrestis L.] largely cultivated in Côte d'Ivoire and consumed as sauce thickeners were analyzed for their proximate composition and compared to a local landrace of ...

  14. On Cultivating Students' Motivation in Second Language Acquisition

    Institute of Scientific and Technical Information of China (English)

    沈小平

    2009-01-01

    This paper attempts to explore the cultivation of motivation in second language acquisition based on shedding new light on the definition, the importance, and the classification of learners' motivation in second language acquisition.

  15. Cultivation of Agaricus bisporus on wheat straw and waste tea ...

    African Journals Online (AJOL)

    Cultivation of Agaricus bisporus on wheat straw and waste tea leaves based composts and locally available casing materials Part III: Dry matter, protein, and carbohydrate contents of Agaricus bisporus.

  16. Microalgal cultivation with biogas slurry for biofuel production.

    Science.gov (United States)

    Zhu, Liandong; Yan, Cheng; Li, Zhaohua

    2016-11-01

    Microalgal growth requires a substantial amount of chemical fertilizers. An alternative to the utilization of fertilizer is to apply biogas slurry produced through anaerobic digestion to cultivate microalgae for the production of biofuels. Plenty of studies have suggested that anaerobic digestate containing high nutrient contents is a potentially feasible nutrient source to culture microalgae. However, current literature indicates a lack of review available regarding microalgal cultivation with biogas slurry for the production of biofuels. To help fill this gap, this review highlights the integration of digestate nutrient management with microalgal production. It first unveils the current status of microalgal production, providing basic background to the topic. Subsequently, microalgal cultivation technologies using biogas slurry are discussed in detail. A scale-up scheme for simultaneous biogas upgrade and digestate application through microalgal cultivation is then proposed. Afterwards, several uncertainties that might affect this practice are explored. Finally, concluding remarks are put forward. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Growth regulators, DNA content and anatomy in vitro -cultivated ...

    African Journals Online (AJOL)

    Growth regulators, DNA content and anatomy in vitro -cultivated Curcuma longa ... Shoots were inoculated in MS culture medium with the addition of 30 g/L of sucrose ... flow cytometry, utilizing two reference standards, green pea, and tomato.

  18. Enhancing Jatropha curcas (Linnaeus) Cultivation and Seed Yield ...

    African Journals Online (AJOL)

    Enhancing Jatropha curcas (Linnaeus) Cultivation and Seed Yield among ... Journal of Agricultural Research and Development ... Jatropha curcas yields substantial quantity of seed oil and is growing in importance as a source of biodiesel.

  19. Morphological classification of genetic diversity in cultivated okra ...

    African Journals Online (AJOL)

    Morphological classification of genetic diversity in cultivated okra, Abelmoschus esculentus (L) Moench using principal component analysis (PCA) and single linkage cluster analysis (SLCA). CC Nwangburuka, OB Kehinde, DK Ojo, OA Denton, AR Popoola ...

  20. Domestication of a Mesoamerican cultivated fruit tree, Spondias purpurea

    OpenAIRE

    Miller, Allison; Schaal, Barbara

    2005-01-01

    Contemporary patterns of genetic variation in crops reflect historical processes associated with domestication, such as the geographic origin(s) of cultivated populations. Although significant progress has been made in identifying several global centers of domestication, few studies have addressed the issue of multiple origins of cultivated plant populations from different geographic regions within a domestication center. This study investigates the domestication history of jocote (Spondias p...

  1. Biochar from commercially cultivated seaweed for soil amelioration

    OpenAIRE

    Roberts, David A.; Paul, Nicholas A.; Dworjanyn, Symon A.; Bird, Michael I.; de Nys, Rocky

    2015-01-01

    Seaweed cultivation is a high growth industry that is primarily targeted at human food and hydrocolloid markets. However, seaweed biomass also offers a feedstock for the production of nutrient-rich biochar for soil amelioration. We provide the first data of biochar yield and characteristics from intensively cultivated seaweeds (Saccharina, Undaria and Sargassum ? brown seaweeds, and Gracilaria, Kappaphycus and Eucheuma ? red seaweeds). While there is some variability in biochar properties as ...

  2. [Synthesis of protective antigens during submerged cultivation of Vibrio cholerae].

    Science.gov (United States)

    Fedorova, V A; Syrova, N A; Gromova, O V; Tershkina, N E; Devdariani, Z L; Dzhaparidze, M N; Meleshchenko, M V; Dobrova, G V; Beliakova, N I; Ermakov, N M; Eliseev, Iu Iu

    2000-01-01

    The effectiveness of dot immunoanalysis for evaluating the dynamics of the synthesis of O-antigen, cholera toxin, neuraminidase, adhesin CFA1 in the process of the reactor cultivation of V. cholerae used for the production of oral chemical cholera vaccine is shown. The established regularities of the synthesis of the protective antigens of V. cholerae in the process of scaled-up cultivation are discussed.

  3. Continuous cultivation of photosynthetic microorganisms: Approaches, applications and future trends.

    Science.gov (United States)

    Fernandes, Bruno D; Mota, Andre; Teixeira, Jose A; Vicente, Antonio A

    2015-11-01

    The possibility of using photosynthetic microorganisms, such as cyanobacteria and microalgae, for converting light and carbon dioxide into valuable biochemical products has raised the need for new cost-efficient processes ensuring a constant product quality. Food, feed, biofuels, cosmetics and pharmaceutics are among the sectors that can profit from the application of photosynthetic microorganisms. Biomass growth in a photobioreactor is a complex process influenced by multiple parameters, such as photosynthetic light capture and attenuation, nutrient uptake, photobioreactor hydrodynamics and gas-liquid mass transfer. In order to optimize productivity while keeping a standard product quality, a permanent control of the main cultivation parameters is necessary, where the continuous cultivation has shown to be the best option. However it is of utmost importance to recognize the singularity of continuous cultivation of cyanobacteria and microalgae due to their dependence on light availability and intensity. In this sense, this review provides comprehensive information on recent breakthroughs and possible future trends regarding technological and process improvements in continuous cultivation systems of microalgae and cyanobacteria, that will directly affect cost-effectiveness and product quality standardization. An overview of the various applications, techniques and equipment (with special emphasis on photobioreactors) in continuous cultivation of microalgae and cyanobacteria are presented. Additionally, mathematical modeling, feasibility, economics as well as the applicability of continuous cultivation into large-scale operation, are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Alternative method for vegetables cultivation in Benin

    Directory of Open Access Journals (Sweden)

    Lucia Recchia

    2013-09-01

    Full Text Available In the developing countries populations, which are already vulnerable and food insecure, are likely to be the most seriously affected by the effects of climate change, e.g. yield decreases and price increases for the most important agricultural crops. The IPCC’s Fourth Assessment Report for Africa describes a trend of warming at a rate faster than the global average and increasing aridity: in many parts of Africa, it seems that warmer climates and changes in precipitation will destabilise agricultural production and aggravates food security. The present work concerns the vegetables cultivation in the Parakou region in Benin, where agriculture employs approximately 70% of the active population and contributes to 36% of the Gross Domestic Product and 88% of export earnings. However, the agricultural sector has been regarded as unproductive with low adaptation capacities because of structural factors (e.g. high level of poverty among rural populations, weak mechanization and intensification of production modes, but also because of natural constraints (e.g. poor management of water and soils, leading to soil degradation. Considering the aridity, the low carbon content and the reduced level of nutrients available in the soil, the use of an hydroponic module has been hypothesised. In this way sufficient yields of the crops may be assured and no agricultural machines will be needed for the tillage operations. In addition, the nutrients can be added to the growing solution using residual materials as poultry manure, ashes and green wastes. In order to verify if some construction or maintenance problems can occur and if a growing solution can be easily obtained using agricultural wastes, some tests have been carried out. Moreover laboratory analyses have been done for different solutions that may be adopted with different shares of water, poultry manure, ashes and green wastes. The tests have indicated that the hydroponic module could be used in Benin

  5. Component analysis of cultivated ginseng, cultivated wild ginseng, and natural wild ginseng by structural parts using HPLC method

    Directory of Open Access Journals (Sweden)

    Young-Ju,Han

    2007-02-01

    Full Text Available Objectives : The aim of this experiments is to provide an objective differentiation of ginseng, Korean and Chinese cultivated wild ginseng, and natural wild ginseng through components analysis of different parts of ginseng. Methods : Comparative analyses of ginsenoside-, ginsenoside-, and ginsenosides and from the root, stem, and leaves of ginseng, Korean and Chinese cultivated wild ginseng, and natural wild ginseng were conducted using HPLC. Results : 1. For content comparison of leaves, ginseng showed highest content of ginsenoside than other samples. Natural wild ginseng showed relatively high content of ginsenosides and than other samples. 2. For content comparison of the stem, ginseng and 10 years old Chinese cultivated wild ginseng didn't contain ginsenoside . Natural wild ginseng showed higher content of ginsenosides and than other samples. 3. For content comparison of the root, ginsenoside was found only in 5 and 10 years old Korean cultivated wild ginseng. 4. Distribution of contents by the parts of ginseng was similar in ginseng and Chinese cultivated wild ginseng. Conclusions : Above experiment data can be an important indicator for the identification of ginseng, Korean and Chinese cultivated wild ginseng, and natural wild ginseng.

  6. [Status of termite-mushroom artificial domestication cultivation--a review].

    Science.gov (United States)

    Zhang, Yujin; Guo, Huachun; Li, Rongchun

    2010-10-01

    Two models of domestication and cultivation of termite-mushroom were discussed: the cultivation of termitomyces model, which method of woodrotting fungi cultivation was emphasized and the original ecological model, which multiplication of symbiotic termites was focused. The problems and possible solutions during termite-mushroom cultivation were also discussed.

  7. Cultivating Microalgae in Domestic Wastewater for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Soha S.M. MOSTAFA

    2012-02-01

    Full Text Available The objective of this study was to evaluate the growth of nine species of microalgae (green and blue green microalgae on domestic waste water samples obtained from Zenein Waste Water Treatment Plant (ZWWTP, Giza governorate, Egypt. The species were cultivated in different kind of waste water; before treatment; after sterilization; with nutrients with sterilization and with nutrients without sterilization. The experiment was conducted in triplicate and cultures were incubated at 25�1�C under continuous shaking (150 rpm and illumination (2000 Lux for 15 days. pH, electric conductivity (EC, optical density (OD , dry weight (DW, were done at the time of incubation and at the end of experiment, in addition to determine the percentage of lipid and biodiesel. The data revealed that, domestic waste water with nutrient media (T3 was promising for cultivation of five algal species when compared with conventional media, Moreover, domestic waste water after sterilization (T2 was selected media for cultivation of Oscillatoria sp and Phormedium sp. However, T1 media (waste water without treatment was the promising media for cultivation of Nostoc humifusum. The biodiesel produced from algal species cultivated in waste water media ranged from 3.8 to 11.80% when compared with the conventional method (3.90 to 12.52%. The results of this study suggest that growing algae in nutrient rich media offers a new option of applying algal process in ZWWTP to mange the nutrient load for growth and valuable biodiesel feedstock production.

  8. Cultivating Microalgae in Domestic Wastewater for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Soha S.M. MOSTAFA

    2012-02-01

    Full Text Available The objective of this study was to evaluate the growth of nine species of microalgae (green and blue green microalgae on domestic waste water samples obtained from Zenein Waste Water Treatment Plant (ZWWTP, Giza governorate, Egypt. The species were cultivated in different kind of waste water; before treatment; after sterilization; with nutrients with sterilization and with nutrients without sterilization. The experiment was conducted in triplicate and cultures were incubated at 251C under continuous shaking (150 rpm and illumination (2000 Lux for 15 days. pH, electric conductivity (EC, optical density (OD , dry weight (DW, were done at the time of incubation and at the end of experiment, in addition to determine the percentage of lipid and biodiesel. The data revealed that, domestic waste water with nutrient media (T3 was promising for cultivation of five algal species when compared with conventional media, Moreover, domestic waste water after sterilization (T2 was selected media for cultivation of Oscillatoria sp and Phormedium sp. However, T1 media (waste water without treatment was the promising media for cultivation of Nostoc humifusum. The biodiesel produced from algal species cultivated in waste water media ranged from 3.8 to 11.80% when compared with the conventional method (3.90 to 12.52%. The results of this study suggest that growing algae in nutrient rich media offers a new option of applying algal process in ZWWTP to mange the nutrient load for growth and valuable biodiesel feedstock production.

  9. Motivation of farmers to cultivate organic rice in Central Java

    Science.gov (United States)

    Dalmiyatun, T.; Eddy, B. T.; Sumekar, W.; Mardiningsih, D.

    2018-01-01

    The consumer’s need for organic agricultural products increases sharply along with awareness of health, lifestyle and environmental concern. This research was intended to determine the relationship between social factors and the motivation of farmers for cultivating organic rice in Central Java. The research has been done by survey to farmers groups at three regions i.e. Semarang, Sragen and Demak. The determination of the location was carried out by means of purposive i.e. farmer groups that conduct organic rice cultivation (not semi organic). The determination of the sample was conducted purposively for a number of 50 people each regencies. Data were analyzed descriptive analysis and rank Spearman correlation analysis. The results showed that social factors include age, cultivated area, education, farming experience have correlation with motivation. education and cultivated area of land has a fairly close relation with correlation value 0,463% and 0,242%. Based on the motivation level, 33% of farmers have high motivation, motivation of farmers varied but most of them, 54% of total farmers stated that the motivation to cultivate organic rice is the quality of organic rice products and high income.

  10. Biomek Cell Workstation: A Variable System for Automated Cell Cultivation.

    Science.gov (United States)

    Lehmann, R; Severitt, J C; Roddelkopf, T; Junginger, S; Thurow, K

    2016-06-01

    Automated cell cultivation is an important tool for simplifying routine laboratory work. Automated methods are independent of skill levels and daily constitution of laboratory staff in combination with a constant quality and performance of the methods. The Biomek Cell Workstation was configured as a flexible and compatible system. The modified Biomek Cell Workstation enables the cultivation of adherent and suspension cells. Until now, no commercially available systems enabled the automated handling of both types of cells in one system. In particular, the automated cultivation of suspension cells in this form has not been published. The cell counts and viabilities were nonsignificantly decreased for cells cultivated in AutoFlasks in automated handling. The proliferation of manual and automated bioscreening by the WST-1 assay showed a nonsignificant lower proliferation of automatically disseminated cells associated with a mostly lower standard error. The disseminated suspension cell lines showed different pronounced proliferations in descending order, starting with Jurkat cells followed by SEM, Molt4, and RS4 cells having the lowest proliferation. In this respect, we successfully disseminated and screened suspension cells in an automated way. The automated cultivation and dissemination of a variety of suspension cells can replace the manual method. © 2015 Society for Laboratory Automation and Screening.

  11. Cultivation of kelp species in the Limfjord, Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Wegeberg, S.

    2010-04-15

    To evaluate the scope of the work and yield of cultivating kelp species in the Danish waters for DONG Energy, Denmark, a pilot?scale cultivation project was initiated in connection with the review of the potential of algal biomass for bio?energy production in Denmark. Two species of large brown algae, sea girdles (Laminaria digitata) and sweet tangle (Saccharina latissima) were cultivated with the expectation to gain maximum biomass yield, partly because of the species' size and partly because of their growth strategy. The result of the pilot study was that sugar seaweed's average maximum length was 7-8 cm, while finger seaweed's length was only 5 cm. The relative small yield is attributable to an overgrowth of sessile animals (hydroids and sea squirts). (ln)

  12. Seaweed cultivation on the Southern and Southeastern Brazilian Coast

    Directory of Open Access Journals (Sweden)

    Franciane Pellizzari

    2011-04-01

    Full Text Available Seaweeds are used directly as food or applied indirectly as texturing agents with gelling and thickening properties (carrageenan, agar and alginates in many industries. They can also be used as fertilizers, animal feed, biomass for fuel, cosmetics and a source of pharmaceuticals, among other applications. The aquaculture of macroalgae is an alternative for producing raw material. Brazil has a coastline with numerous locations suitable for this endeavor. However, despite the known economical and social relevance of seaweed cultivation, Brazilians do not have tradition of using edible seaweeds. In general, the raw material for indirect use (e.g., as a texturing agent is imported. Consequently, seaweed aquaculture is still incipient in Brazil. This contribution presents data and information about macroalgae cultivation on commercial and experimental scales performed on the Southern and Southeastern Brazilian Coastline, as well as a brief overview of research related to some species cultivated in the last decade.

  13. INTENSIFICATION OF JELLY MUSHROOM CULTIVATION IN PAKEM SLEMAN

    Directory of Open Access Journals (Sweden)

    Sulistiya

    2015-01-01

    Full Text Available Mushroom cultivation is long enough to be a source of income for some people in Pakem, Sleman. However, cultivation techniques that do not yet meet the standards for technical, so that productivity is still low. Marketing mushrooms are limited to the traditional market. Waste mushroom has not been used well, so potentially to pollute the environment mushroom. This service activities include the provision of mushroom cultivation equipment, such as water pumps and termohygrometer and nozzle, and education and training bookkeeping, marketing, and processing waste into mushroom compost. The results showed an increase in the production of mushroom seen from the Biological Conversion Efficiency (BCE are in the top 30 percent. Partners also has a business bookkeeping and have Blog to market the mushroom by on-line. Partners also have the skills to process the manure (compost made from the waste of mushroom which can be used to help fertilize their crops.

  14. Spatial distribution models of erosion on slopes cultivated with vineyards

    International Nuclear Information System (INIS)

    Armaez, J.; Ortigosa, L.; Ruiz-Falno, P.; Llorente, J. A.; Lasanta, T.

    2009-01-01

    Soils cultivated with vineyards have high rates of erosion. In the Mediterranean area, this is related to the environmental characteristics and the management of cultivation techniques. Indeed, in this region the rainfall intensity and the location of vineyards on slopes favour the erosive activity of runoff. The total area of vineyards in La Rioja (Spain) is currently almost 40,000 ha. Vineyards are located on hillsides between 400 and 60 m.a.s.l. Of the vineyards of La Rioja 81,7% are planted on slopes with a gradient between 3 degree centigrade and 9 degree centigrade. (Author) 5 refs.

  15. Cytogenetic characterization of Encyclia caximboensis cultivated in vitro (Orchidaceae)

    OpenAIRE

    Gizelly Mendes Silva; Tatiane Lemos Varella; Kaliane Maximiliano Cruz; Ilio Fealho Carvalho; Isane Vera Karsburg; Maurecilne Lemes Silva

    2015-01-01

    Encyclia caximboensis is an Amazonian species endemic to the Serra do Cachimbo, which is located between the northern of the Mato Grosso state and the southern part of Para state. Studies reporting in vitro cultivation and cytogenetic characterization of this species are still scarce. Therefore, the objective of this work was to determine the cytogenetic characteristics and to identify the nucleolar organizer regions (NORs) of the species E. Caximboensis, cultivated in vitro. Seeds of E. caxi...

  16. Nootropic activity of extracts from wild and cultivated Alfredia cernua.

    Science.gov (United States)

    Mustafin, R N; Shilova, I V; Suslov, N I; Kuvacheva, N V; Amelchenko, V P

    2011-01-01

    Antihypoxic and nootropic activities of extracts from aerial parts of wild and cultivated Alfredia cernua (L.) Cass. were studied on the models of pressure chamber hypoxia, open field test, and passive avoidance conditioning. The extracts of Alfredia cernua promoted retention of the orientation reflex and passive avoidance conditioned response and normalized orientation and exploratory activities disordered as a result of hypoxic injury. The efficiency of the extracts was superior to that of piracetam by the effect on retention of passive avoidance response throughout the greater part of the experiment. Nootropic activity of cultivated Alfredia cernua was not inferior to that of the wild plant.

  17. Influences of Urban Expansion on Cultivated Lands in China Since 1970S

    Science.gov (United States)

    Liu, F.; Zhang, Z.; Zhao, X.; Yu, S.; Wang, X.; Zuo, L.

    2018-04-01

    Urban expansion has far-reaching influences on cultivated lands, and has a serious effect on grain output and safety. However, relatively little attention has been paid to monitor cultivated land losses through urban expansion over a long timeframe and multi-frequency, especially its differences on national scale systematically. In this work, the characteristics of Chinese cultivated land dynamics were described using annual occupied area per city, contribution rate of cultivated lands to urban expansion and the classification method of basic trend of cultivated land losses. Results indicate that: (1) in the past four decades, large amount of cultivated lands have been occupied during the urban expansion process, and have become the first land source for Chinese urban expansion. (2) Cultivated land loss among municipalities, provincial capitals and other cities was obviously different. The higher of cities' administrative level was, the more obvious of cultivated land loss in these cities appeared, and the earlier of acceleration loss stage of cultivated lands occurred. (3) Cultivated land loss in five population-size cities was unbalanced, representing obviously different loss process and contribution on urban expansion. The bigger of cities' population size was, the more obvious of cultivated land loss in these cities appeared, and the earlier of acceleration loss stage of cultivated lands occurred. (4) Cultivated land losses during urban expansion process were imbalanced in China, and were classified into seven trends. (5) Chinese cultivated land protection has been carried out from the awakening stage to the deep implementation stage.

  18. Feasibility Study on Sterilization of Badge using Radiation and Cultivation by Nano-bubble Water for Matsutake Mushroom Cultivation

    International Nuclear Information System (INIS)

    Jung, Inha

    2013-12-01

    This report on the 'Sterilization of Badge using Radiation and Cultivation by Nano-bubble Water for Matsutake Mushroom Cultivation' is belonged to the final report on the preliminary study of the first subject in 2013 for civilian project. This was complimented on the responsible of the Korea Atomic Energy Research Institute for 1 st of June 2013 to 30 th of November 2013. We are going to make sterilization the badge using the gamma ray and supplying the oxygen by nano-bubble oxygen rich water for cultivating the Matsutake Mushroom, instead of the conventional process of sterilization of the badge by hot steam over 120 .deg. C consuming over 8 hours and expensive ventilation system for supplying the fresh air for delivering the oxygen

  19. Feasibility Study on Sterilization of Badge using Radiation and Cultivation by Nano-bubble Water for Matsutake Mushroom Cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Inha

    2013-12-15

    This report on the 'Sterilization of Badge using Radiation and Cultivation by Nano-bubble Water for Matsutake Mushroom Cultivation' is belonged to the final report on the preliminary study of the first subject in 2013 for civilian project. This was complimented on the responsible of the Korea Atomic Energy Research Institute for 1{sup st} of June 2013 to 30{sup th} of November 2013. We are going to make sterilization the badge using the gamma ray and supplying the oxygen by nano-bubble oxygen rich water for cultivating the Matsutake Mushroom, instead of the conventional process of sterilization of the badge by hot steam over 120 .deg. C consuming over 8 hours and expensive ventilation system for supplying the fresh air for delivering the oxygen.

  20. Component Analysis of Cultivated Ginseng, Red Ginseng, Cultivated Wild Ginseng, and Red Wild Ginseng Using HPLC Method

    Directory of Open Access Journals (Sweden)

    Jang Ho, Lee

    2008-06-01

    Full Text Available Objectives : The aim of this experiment is to provide an differentiation of ginseng, red ginseng, cultivated wild ginseng(CWG, and red wild ginseng(RWG through component analysis using HPLC(High Performance Liquid Chromatography, hereafter HPLC. Methods : Comparative analyses of ginsenoside Rg3, ginsenoside Rh2, and ginsenosides Rb1 and Rg1 of various ginsengs were conducted using HPLC. Results : 1. CWG was relatively heat-resistant and showed slow change in color during the process of steaming and drying, compared to cultivated ginseng. 2. Ginsenoside Rg3 was not detected in cultivated ginseng and CWG, whereas it was high in red ginseng and RWG. Ginsenoside Rg3 was more generated in red ginseng than in RWG. 3. Ginsenoside Rh2 appreared during steaming and drying of cultivated ginseng, whereas it was more increased during steaming and drying of CWG. 4. Ginsenoside Rg1 content was more increased during steaming and drying of cultivated ginseng, whereas it was more decreased during steaming and drying of CWG. 5. Ginsenoside Rb1 content was increased about 500% during steaming and drying of cultivated ginseng, whereas it was increased about 30% during steaming and drying of CWG, indicating that ginsenoside Rb1 was more generated in red ginseng than in RWG. 6. Ginsenoside Rg3 content was higher, whereas ginsenoside Rg1 content was lower in 11th RWG than in 9th RWG, indicating that ginsenoside Rg3 content was increased and Rg1 content was decreased as steaming and drying continued to proceed. Ginsenoside Rh2 and Rb1 contents began to be increased, followed by decreased after 9th steaming and drying process. Conclusions : Above experiment data can be an important indicator for the identification of ginseng, red ginseng, CWG, and RWG. And the following studies will be need for making good product using CWG.

  1. Buddhist Pedagogy in Teacher Education: Cultivating Wisdom by Skillful Means

    Science.gov (United States)

    Ma Rhea, Zane

    2018-01-01

    This paper draws on research I have conducted about the cultivation of wisdom in Thailand and Australia. I examine the ancient pedagogy of pavi?aupaya skillful means investigating how this pedagogy can inform contemporary development of teacher educators and teachers. I examine the Panjaawi´tee Wisdom Method that has its foundations in the…

  2. Cultivating Teachers' Morality and the Pedagogy of Emotional Rationality

    Science.gov (United States)

    Kim, Minkang

    2013-01-01

    Teachers are expected to act ethically and provide moral role models in performing their duties, even though teacher education has often relegated the cultivation of teachers' ethical awareness and moral development to the margins. When it is addressed, the main theoretical assumptions have relied heavily on the cognitivist developmental theories…

  3. Wanted: Information on the Distribution of Cultivated Plants

    Science.gov (United States)

    Howard, Richard A.

    1970-01-01

    Lack of documentation makes it very difficult to discover where species of cultivated plants may be found in the United States. Plead for compilation of "campus floras and herbarium collections. Need for a rational locator file of available plant materials. Lists and reviews present sources of information. Bibliography of campus floras. (EB)

  4. Characteristics of papillae in wild, cultivated and hybrid sea ...

    African Journals Online (AJOL)

    We investigated the characteristics of papillae of living, boiled and dried specimens of three wild populations, cultivated and hybrid Apostichopus japonicus in the laboratory. Visual observation showed that the appearance of the papillae was obviously different among the populations. For the first time, we established a ...

  5. On Design Experiment Teaching in Engineering Quality Cultivation

    Science.gov (United States)

    Chen, Xiao

    2008-01-01

    Design experiment refers to that designed and conducted by students independently and is surely an important method to cultivate students' comprehensive quality. According to the development and requirements of experimental teaching, this article carries out a study and analysis on the purpose, significance, denotation, connotation and…

  6. Status of jatropha cultivation for biodiesel production in Pakistan

    International Nuclear Information System (INIS)

    Khan, N.A.; Usmani, J.N.

    2010-01-01

    Pakistan is highly dependent on imported fuels. Sustainable production of biodiesel presents an opportunity to reduce reliance on imported oil, save foreign-exchange reserves, reduce poverty and unemployment, stimulate rural development in areas with acute poverty and enhance access to renewable commercial energy. We are an agriculture-based economy; therefore, production of Bio diesel by utilizing agro-base cultivation will strengthen our agricultural sector and empower the farmers. Moreover, the country has immense potential to attain energy-security through domestic cultivation and processing of bio fuel crops. Some details of the processing plant and manufacturing are also given. This paper describes and delineates the present status of Jatropha cultivation in Pakistan. An attempt is made to project the future of bio diesel, through Jatropha seeds and simultaneous efforts to cultivate other bio diesel- producing seeds to make its cost as low as possible. This paper can also be taken as a base to predict the minimum time required to produce 5-10% replacement of mineral diesel by biodiesel. (author)

  7. Continuous Cultivation of Photosynthetic Bacteria for Fatty Acids Production

    DEFF Research Database (Denmark)

    Kim, Dong-Hoon; Lee, Ji-Hye; Hwang, Yuhoon

    2013-01-01

    In the present work, we introduced a novel approach for microbial fatty acids (FA) production. Photosynthetic bacteria, Rhodobacter sphaeroides KD131, were cultivated in a continuous-flow, stirred-tank reactor (CFSTR) at various substrate (lactate) concentrations.At hydraulic retention time (HRT)....... sphaeroides was around 35% of dry cell weight, mainly composed of vaccenic acid (C18:1, omega-7)....

  8. Farmers' perception of risk in cultivating hybrid rice in Bangladesh ...

    African Journals Online (AJOL)

    Although there is an enormous potential for improving adoption of hybrid rice in Bangladesh, it is going through some difficulties in practice. Understanding farmers' perception about difficulties is critical to successful promotion. The present study was conducted to analyze farmers' perception of risk in cultivating hybrid rice ...

  9. Lignocellulose pretreatment in a fungus-cultivating termite

    Science.gov (United States)

    Hongjie Li; Daniel J. Yelle; Chang Li; Mengyi Yang; Jing Ke; Ruijuan Zhang; Yu Liu; Na Zhu; Shiyou Liang; Xiaochang Mo; John Ralph; Cameron R. Currie; Jianchu Mo

    2017-01-01

    Depolymerizing lignin, the complex phenolic polymer fortifying plant cell walls, is an essential but challenging starting point for the lignocellulosics industries. The variety of ether– and carbon–carbon interunit linkages produced via radical coupling during lignification limit chemical and biological depolymerization efficiency. In an ancient fungus-cultivating...

  10. Technologies of Self and the Cultivation of Virtues

    Science.gov (United States)

    Hattam, Robert; Baker, Bernadette

    2015-01-01

    In this article we engage with and against Foucault's provocation to think about diagrams of subjectivation. With Foucault we take up his meditation on spirituality and propose a Buddhist alternative to Greco-Roman technologies of self. Against Foucault's notion of an "arts of existence" we suggest instead "cultivation of…

  11. Seed constraint to cultivation and productivity of African indigenous ...

    African Journals Online (AJOL)

    Non-availability of improved seeds constitutes a major constraint to the cultivation and productivity of the indigenous leaf vegetables (ILVs) of Africa. Research on African ILVs has focused mainly on the ethnobotany, collection, preservation, and the assessment of food value and chemical composition of the ILVs. No serious ...

  12. Religion and the Cultivation of Citizenship in Chinese Higher Education

    Science.gov (United States)

    Zhao, Zhenzhou

    2017-01-01

    A growing body of research has documented the escalating popularity of religion among student populations in China's higher education settings. Despite the changes sustained by China's religious policies throughout the post-Mao era, the state has not abandoned its long-standing approach of cultivating citizenship through Marxist-Leninist-oriented…

  13. Cultivation of Agaricus bisporus on some compost formulas and ...

    African Journals Online (AJOL)

    Three compost formulas; wheat straw based and using different activator materials such as wheat brain, chicken manure, and pigeon manure were used for Agaricus bisporus cultivation. Locally available casing materials such as peat of Bolu, peat of Agacbasi, peat of Caykara, and their mixture (80:20; v:v) with perlite were ...

  14. Cultivation of Agaricus bisporus on some compost formulas and ...

    African Journals Online (AJOL)

    Three compost formulas (formula I, formula II, and formula III) based waste tea leaves and using some activator materials such as wheat bran, chicken manure and pigeon manure were studied for Agaricus bisporus cultivation. Some locally available peats such as peat of Bolu, peat of Agacbasi, peat of Caykara and theirs ...

  15. On the capitalization and cultivation of social capital

    DEFF Research Database (Denmark)

    Waldstrøm, Christian; Svendsen, Gunnar Lind Haase

    2008-01-01

    a dual focus on social capital as both immediately and potentially productive resources, i.e. assets that can be immediately capitalized by individuals as well as ‘cultivated' for future use. We argue that to further operationalize this concept we must distinguish between actual/potential social capital...

  16. Concerted Cultivation and Music Learning: Global Issues and Local Variations

    Science.gov (United States)

    Ilari, Beatriz

    2013-01-01

    "Concerted cultivation" has been described as a common, urban middle-class practice concerning the enrollment of children in a variety of age-specific activities that may promote the learning of valuable life skills as well as the development of individual abilities (Lareau, 2003). Music is one such activity. This study investigated the…

  17. On the use of selective environments in microalgal cultivation

    NARCIS (Netherlands)

    Mooij, P.R.

    2016-01-01

    This thesis deals with selective environments in microalgal cultivation. As explained in Chapter 1 microalgae have changed the course of life on Earth dramatically by performing oxygenic photosynthesis. In oxygenic photosynthesis electrons from water are used to reduce carbon dioxide to

  18. Comparisons of dioxin levels of cucumber varieties and cultivation periods

    Energy Technology Data Exchange (ETDEWEB)

    Eun, H.; Watanabe, E.; Ishii, Y.; Ueji, M. [National Inst. for Agro-Environmental Sciences, Tsukuba (Japan); Narita, I.; Nakamura, K. [Saitama Prefecture Agriculture and Forestry Research Center, Saitama (Japan)

    2004-09-15

    According to a 2001 survey on Daily Intake in Japan, the total dioxins intake of a person in Japan amounts to 1.68 pg-TEQ per kg of body weight/day on average. The sharing a percentage of agricultural crops was about 3%in Japanese TDI amounts. However, all cases collect samples from supermarkets to estimate TDI of dioxins, which make it difficult to understand under what environment, food samples were pretreated and cultivated. Especially, TDI values in agricultural crops are probably dependent on the collection situation. In the agricultural environment, some reports indicate that dioxins have accumulated in paddy and upland in Japan due to the past use of some types of agricultural chemicals, which contained dioxins as impurities. Furthermore, taking the atmospheric pathway, for example, dioxins in the ambient air are associated with particulate matter and fall to the ground, contaminating agricultural land. Thus, it has been emphasized that dioxin compounds have a possibility to have adverse effect on vegetables. However, there is little understanding related to this fact in the country and worldwide. Empirical studies conducted in Japan and abroad have reported low residual concentrations of dioxins in cucumbers (Cucumis sativus L.), a member of the gourd family. However, there have been extremely few instances of research involving overall comparisons of cultivation environments. Thus, we studied the persistence of dioxins in cucumbers of different varieties cultivated outdoors over varying cultivation periods, conducting thorough experiments to elucidate the actual conditions and mechanisms of dioxin contamination of cucumbers.

  19. Sequencing of a Cultivated Diploid Cotton Genome-Gossypium arboreum

    Institute of Scientific and Technical Information of China (English)

    WILKINS; Thea; A

    2008-01-01

    Sequencing the genomes of crop species and model systems contributes significantly to our understanding of the organization,structure and function of plant genomes.In a `white paper' published in 2007,the cotton community set forth a strategic plan for sequencing the AD genome of cultivated upland cotton that initially targets less complex diploid genomes.This strategy banks on the high degree

  20. Cultivating Critical-Thinking Dispositions throughout the Business Curriculum

    Science.gov (United States)

    Bloch, Janel; Spataro, Sandra E.

    2014-01-01

    Critical thinking is an essential component of managerial literacy, yet business school graduates struggle to apply critical-thinking skills at work to the level that employers desire. This article argues for a dispositional approach to teaching critical thinking, rooted in cultivating a critical-thinking culture. We suggest a two-pronged approach…

  1. Cultivation of algae in photobioreator and obtention of biodiesel

    Directory of Open Access Journals (Sweden)

    Cristiane B. Hobuss

    2011-04-01

    Full Text Available In this work we described the cultivation of Chlorella vulgaris in a photobioreactor to algal biomass production. The dried biomass was used as feedstock for biodiesel production, it presented 26% lipids and via sonocatalysis stage of the methodology resulted in 60% of fatty acid methyl esters (FAME. The FAME content was confirmed by Gas Chromatography (GC.

  2. Do Specialized MBA Programs Cultivate Alumni Relationships and Donations?

    Science.gov (United States)

    Johnson, Jennifer Wiggins; Thomas, Veronica; Peck, Joann

    2010-01-01

    A recent trend among universities shifts from traditional MBA programs to specialized MBA offerings. Specialized programs are believed to cultivate stronger relationships with students, which lead to stronger alumni relationships and increased donations. This research tests this empirically by examining relationship perceptions and donation…

  3. Inferring ancient Agave cultivation practices from contemporary genetic patterns.

    Science.gov (United States)

    Parker, Kathleen C; Trapnell, Dorset W; Hamrick, J L; Hodgson, Wendy C; Parker, Albert J

    2010-04-01

    Several Agave species have played an important ethnobotanical role since prehistory in Mesoamerica and semiarid areas to the north, including central Arizona. We examined genetic variation in relict Agave parryi populations northeast of the Mogollon Rim in Arizona, remnants from anthropogenic manipulation over 600 years ago. We used both allozymes and microsatellites to compare genetic variability and structure in anthropogenically manipulated populations with putative wild populations, to assess whether they were actively cultivated or the result of inadvertent manipulation, and to determine probable source locations for anthropogenic populations. Wild populations were more genetically diverse than anthropogenic populations, with greater expected heterozygosity, polymorphic loci, effective number of alleles and allelic richness. Anthropogenic populations exhibited many traits indicative of past active cultivation: fixed heterozygosity for several loci in all populations (nonexistent in wild populations); fewer multilocus genotypes, which differed by fewer alleles; and greater differentiation among populations than was characteristic of wild populations. Furthermore, manipulated populations date from a period when changes in the cultural context may have favoured active cultivation near dwellings. Patterns of genetic similarity among populations suggest a complex anthropogenic history. Anthropogenic populations were not simply derived from the closest wild A. parryi stock; instead they evidently came from more distant, often more diverse, wild populations, perhaps obtained through trade networks in existence at the time of cultivation.

  4. Kant and Rawls on the Cultivation of Virtue

    Science.gov (United States)

    Brewer, Talbot

    2013-01-01

    In "Two Conceptions of Virtue," Thomas Hill reconstructs the conceptions of virtue, and of proper moral upbringing, found in Kant and Rawls. Here I offer some brief reflections on these conceptions of virtue and its cultivation. I argue that Kant's conception of virtue is grounded in a mistaken conception of desire, and that this…

  5. What quantitative mechanical loading stimulates in vitro cultivation best?

    NARCIS (Netherlands)

    Natenstedt, Jerry; Kok, Aimee C.; Dankelman, Jenny; Tuijthof, Gabrielle J. M.

    2015-01-01

    Articular cartilage has limited regeneration capacities. One of the factors that appear to affect the in vitro cultivation of articular cartilage is mechanical stimulation. So far, no combination of parameters has been identified that offers the best results. The goal is to review the literature in

  6. Triple Hybridization with Cultivated Barley (Hordeum vulgare L.)

    DEFF Research Database (Denmark)

    Bothmer, R. von; Claesson, L.; Flink, J.

    1989-01-01

    A crossing programme for trispecific hybridization including cultivated barely (Hordeum vulgare L.) as the third parent was carried out. The primary hybrids comprised 11 interspecific combinations, each of which had either H. jabatum or H. lechleri as one of the parents. The second parent...

  7. Cultivation of Schizophyllum commune mushroom on different wood substrates

    Directory of Open Access Journals (Sweden)

    P.N. Dasanayaka

    2017-07-01

    Full Text Available Schizophyllum commune is an edible mushroom grown on wood under natural conditions. Present study focused on cultivation of S.commune on different wood substrates since it is not commercially cultivated. A pure culture of S. commune was obtained by growing a tissue of the mushroom on Potato Dextrose Agar (PDA medium. Spawns were produced by growing the mycelium on paddy grains. Mushroom was cultivated on sawdust of seven different wood substrates. The maximum yield was observed in sawdust of jackfruit (Artocarpusheterophyllus followed by sawdust of rambutan (Nepheliumlappaceum and country almond (Terminaliacatappa. A significant difference was not observed when mango (Mangiferaindica elephant apple (Dilleniaindica, tulip wood tree (Harpulliaarborea and thungfaa (Alstoniamacrophylla sawdust used as substrate. The lowest yield was observed in thungfaa (Alstoniamacrophylla sawdust. Effect of some additives on the yield was studied and significant difference in yield was observed when rice bran and used-tea leaves used as additives. Effect of rice bran on yield was studied using different ratios of sawdust to rice bran and the highest was observed in 2:1 ratio of sawdust to rice bran. The best incubating temperature for mycelial growth on the substrate was 350C. The composition of the mushroom on a dry weight basis was; 71.4% moisture, 23.35% crude protein and 6% ash. Tested wood species are promising substrates for cultivation of S.communeas cottage industry.

  8. The case for small-scale domestic cannabis cultivation.

    Science.gov (United States)

    Decorte, Tom

    2010-07-01

    The shift to (inter)regional production, trade and domestic cultivation has become an irreversible international trend. Until now, the focus of most empirical work has been on large-scale, commercially oriented and professionally organized segments of the cannabis industry, often based on police data and on the perspective of law enforcement agencies. This paper offers a review of recent Dutch-language research that focuses on cannabis cultivation. Empirical studies were identified through literature searches using relevant search terms and Web of Science, Elin, Social Science Research Network and Elsevier ScienceDirect. The paper presents the main findings of Dutch and Belgian empirical work on the factors that stimulated the import substitution process on the cannabis market, aspects related to quality and potency issues, typologies of cannabis growers, and (unintended) effects of pursued policies. In the light of this (selective) review the author offers some commentary and analysis concerning the claims made by different stakeholders, and concludes with some reflections on future research and on policy implications. The author outlines the importance of small-scale, independent or ideologically oriented cannabis cultivation as an under-researched market segment. The author also makes a case for greater toleration of small-scale cannabis cultivation, to secure the least worst of cannabis markets. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  9. Genetic analysis of wild and cultivated germplasm of pigeonpea ...

    African Journals Online (AJOL)

    To compare the efficiency of the use of single versus multiple markers, the genetic diversity was quantified among 12 diverse pigeonpea germplasm comprised of eight wild and four cultivated using both random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers, and how well these two types ...

  10. Cultivation, isolation and characterization of bacteriocin from fresh ...

    African Journals Online (AJOL)

    This study focus on cultivation, isolation and characterization of Bacteriocin from fresh cow milk (FCM) and fresh cow meat (FMS) samples obtained from Lapai Market in Niger State, Nigeria. Potential bacteriocinogenic bacteria were screened with agar diffusion method on culture plates seeded with Staphylococcus and ...

  11. Recent advances in periodontal microbiology: An update on cultivation techniques

    Directory of Open Access Journals (Sweden)

    Kishore G Bhat

    2014-01-01

    Full Text Available Microbial members of the subgingival plaque community play a major role in the initiation and progression of periodontal diseases. Majority of these bacteria are anaerobic in nature and several anaerobic systems have been used for their cultivation. Among them anaerobic jars are the most popular and are routinely used for the detection of periodontal pathogens from clinical samples. Despite best efforts, a significant portion of oral microbes have not yet been cultivated and several hypotheses have been put forth to explain this anomaly. This has led to renewed efforts to cultivate the oral bacteria so far identified only by their molecular signatures resulting in improvisation of existing culture techniques and devising novel methods of isolation. Several devices have been used on environmental samples successfully: One method called "minitrap" has been successfully adapted to oral cavity and has shown great promise in isolation of not yet cultivated oral bacterial species. These newer techniques are sure to shed more light on the role of microbes in the etiology of periodontal diseases.

  12. Effects of different cultivation techniques on vineyard fauna

    OpenAIRE

    Mikulas, J.; Kutasi, Cs.; Mark, V.; Balog, A.

    2002-01-01

    Green covering compared to soil cultivation enhanced the number of individuals of Araneae living on or near soil. No differences between the different soil management systems were found for the number of individuals of Staphylinidae and Carabidae. The typical main species of the two systems were different for all groups analyzed (Araneae, Staphylinidae and Carabidae).

  13. Sharing and Cultivating Tacit Knowledge in an Online Learning Environment

    Science.gov (United States)

    Tee, Meng Yew; Karney, Dennis

    2010-01-01

    Research on knowledge cultivation often focuses on explicit forms of knowledge. However, knowledge can also take a tacit form--a form that is often difficult or impossible to tease out, even when it is considered critical in an educational context. A review of the literature revealed that few studies have examined tacit knowledge issues in online…

  14. The art of cultivation (på kinesisk)

    DEFF Research Database (Denmark)

    Hauxner, Malene

    2007-01-01

     All art forms have their own language. As music has its sound language, ballet has its step language and film has its film language, landscape architecture also has its specific language. As an art of cultivation it has two, which I call an agricultural and a pastoral language corresponding to two...

  15. Bacteria associated with compost used for cultivation of Nigerian ...

    African Journals Online (AJOL)

    The bacteria involved in an outdoor single phase composting using sawdust and wheat bran as substrates for cultivation of Pleurotus tuber-regium (Fr.) Singer, and Lentinus squarrosulus (Berk.), two Nigerian edible mushrooms were identified. Composting was carried out for 2 weeks. The highest core and peripheral ...

  16. Trends in shifting cultivation and the REDD mechanism

    DEFF Research Database (Denmark)

    Mertz, Ole

    2009-01-01

    of the transitions taking place. The proposed mechanism for reduced greenhouse gas emissions from deforestation and degradation (REDD) can be both a challenge and opportunity for shifting cultivators. Very limited literature is available on this dilemma, but a few sources point to benefits from ‘compensated...

  17. Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    The Algae Cultivation for Carbon Capture and Utilization Workshop Summary Report summarizes a workshop hosted by the U.S. Department of Energy's Bioenergy Technologies Office on May 23–24, 2017, in Orlando, Florida. The event gathered stakeholder input through facilitated discussions focused on innovative technologies and business strategies for growing algae on waste carbon dioxide resources.

  18. Cultivation of mushroom ( Pleurotus ostreatus ) using corn cobs and ...

    African Journals Online (AJOL)

    An investigation was carried out on the cultivation of mushroom (Pleurotus ostreatus) using corn cobs and saw dust as the main substrates. Lignocellulosic wastes such as corn cobs and saw dust were packaged inside heat – resistant polythene bags and pasteurized before being seeded with 7.5% w/w millet spawn of ...

  19. [Species diversity of ex-situ cultivated Chinese medicinal plants].

    Science.gov (United States)

    Que, Ling; Chi, Xiu-Lian; Zang, Chun-Xin; Zhang, Yu; Chen, Min; Yang, Guang; Jin, An-Qi

    2018-03-01

    Ex-situ conservation is an important means to protect biological genetic resources. Resource protection has received more and more attention with the continuous improvement of the comprehensive utilization of traditional Chinese medicine resources. In this paper, the research and compilation of the species list of ex-situ cultivated medicinal plants in 12 Chinese Academy of Sciences botanic gardens and 19 specialized medicinal botanic gardens in China were carried out. Based on the Species 2000(2017) and other classification databases, species diversity of medicinal plants ex-situ cultivated in these botanical gardens were analyzed. The study found that there were 16 351 higher plant species in our country, belonging to 276 families and 1 936 genera. Of these, 6 949 specieswere medicinal plants, accounting for 50.4% of the total medicinal plants. There were 1 280 medicinal plants were in threatened status, accounting for 19.6% of all threatened species in the Chinese Biodiversity Red List, with ex-situ cultivated proportion of 59.5%. And 3 988 medicinal plants were Chinese endemic species, accounting for 22.5% of all Chinese endemic species, with ex-situ cultivated proportion of 53.3%. This article has reference significance for the management and protection of medicinal plant resources. Copyright© by the Chinese Pharmaceutical Association.

  20. Self-Cultivation: Culturally Sensitive Psychotherapies in Confucian Societies

    Science.gov (United States)

    Hwang, Kwang-Kuo; Chang, Jeffrey

    2009-01-01

    This article describes self-cultivation practices originating from the cultural traditions of Confucianism, Taoism, and Buddhism. It delineates the therapeutic implications of the three states of self pursued by these three traditions: namely, the "relational self", the "authentic self", and the "nonself". Several…

  1. Cultivation of the microalga, Chlorella pyrenoidosa , in biogas ...

    African Journals Online (AJOL)

    Therefore, the microalga was introduced to be cultivated in the biogas wastewater, which could not only bioremediate the wastewater, but also produce plenty of the microalga biomass that could be used for the exploitation of fertilizers, feed additives and biofuels. This study showed that the microalga, C. pyrenoidosa could ...

  2. Parenting Priorities and Pressures: Furthering Understanding of "Concerted Cultivation"

    Science.gov (United States)

    Vincent, Carol; Maxwell, Claire

    2016-01-01

    This paper re-examines the purposes of a planned and intentional parenting style--"concerted cultivation"--for different middle-class groups, highlighting that social class fraction, ethnicity, and also individual family disposition, guides understandings of the purposes of enrolling children in particular enrichment activities. We…

  3. Closing the water and nutrient cycles in soilless cultivation systems

    NARCIS (Netherlands)

    Beerling, E.A.M.; Blok, C.; Maas, van der A.A.; Os, van E.A.

    2014-01-01

    Soilless cultivation systems are common in Dutch greenhouse horticulture, i.e., less than 20% of the greenhouse area is still soil grown. For long, it was assumed that in these so-called closed systems the emission of nutrients and plant protection products (PPPs) was close to zero. However, Water

  4. Pleurotus pulmonarius cultivation on amended palm press fibre waste

    African Journals Online (AJOL)

    In the last few decades, rapid global demand for edible oils has resulted in a significant increase in the land area of oil crop cultivation. In the process of extraction of palm oil from oil palm fruit, biomass materials such as palm pressed fibre (PPF) are generated as waste products. This research was undertaken to evaluate ...

  5. Suitability of Nigerian Weather Conditions for Cultivation of Microalgae

    African Journals Online (AJOL)

    Client

    compared with optimal conditions for cultivation of various species of microalgae. ... The results of average hours of sunshine showed that Jos has the lowest number of hours ... Temperature stratification in ponds within Abakaliki was ... question of how we will feed the starving masses of our ever increasing world population.

  6. Submerged cultivation of medicinal mushrooms: bioprocesses and products (review).

    Science.gov (United States)

    Elisashvili, Vladimir

    2012-01-01

    Medicinal mushrooms belonging to higher Basidiomycetes are an immensely rich yet largely untapped resource of useful, easily accessible, natural compounds with various biological activities that may promote human well-being. The medicinal properties are found in various cellular components and secondary metabolites (polysaccharides, proteins and their complexes, phenolic compounds, polyketides, triterpenoids, steroids, alkaloids, nucleotides, etc.), which have been isolated and identified from the fruiting bodies, culture mycelium, and culture broth of mushrooms. Some of these compounds have cholesterol-lowering, anti-diabetic, antioxidant, antitumor, immunomodulating, antimicrobial, and antiviral activities ready for industrial trials and further commercialization, while others are in various stages of development. Recently, the submerged cultivation of medicinal mushrooms has received a great deal of attention as a promising and reproducible alternative for the efficient production of mushroom mycelium and metabolites. Submerged cultivation of mushrooms has significant industrial potential, but its success on a commercial scale depends on increasing product yields and development of novel production systems that address the problems associated with this technique of mushroom cultivation. In spite of many researchers' efforts for the production of bioactive metabolites by mushrooms, the physiological and engineering aspects of submerged cultures are still far from being thoroughly studied. The vast majority of studies have focused on polysaccharide and ganoderic acid production in submerged cultivation of medicinal mushrooms, and very little has been written so far on the antioxidant and hemagglutinating activity of submerged mushroom cultures. The purpose of this review is to provide an update of the present state of the art and future prospects of submerged cultivation of medicinal mushrooms to produce mycelium and bioactive metabolites, and to make a

  7. Gene flow and genetic diversity in cultivated and wild cacao (Theobroma cacao) in Bolivia.

    Science.gov (United States)

    Chumacero de Schawe, Claudia; Durka, Walter; Tscharntke, Teja; Hensen, Isabell; Kessler, Michael

    2013-11-01

    The role of pollen flow within and between cultivated and wild tropical crop species is little known. To study the pollen flow of cacao, we estimated the degree of self-pollination and pollen dispersal distances as well as gene flow between wild and cultivated cacao (Theobroma cacao L.). We studied pollen flow and genetic diversity of cultivated and wild cacao populations by genotyping 143 wild and 86 cultivated mature plants and 374 seedlings raised from 19 wild and 25 cultivated trees at nine microsatellite loci. A principal component analysis distinguished wild and cultivated cacao trees, supporting the notion that Bolivia harbors truly wild cacao populations. Cultivated cacao had a higher level of genetic diversity than wild cacao, presumably reflecting the varied origin of cultivated plants. Both cacao types had high outcrossing rates, but the paternity analysis revealed 7-14% self-pollination in wild and cultivated cacao. Despite the tiny size of the pollinators, pollen was transported distances up to 3 km; wild cacao showed longer distances (mean = 922 m) than cultivated cacao (826 m). Our data revealed that 16-20% of pollination events occurred between cultivated and wild populations. We found evidence of self-pollination in both wild and cultivated cacao. Pollination distances are larger than those typically reported in tropical understory tree species. The relatively high pollen exchange from cultivated to wild cacao compromises genetic identity of wild populations, calling for the protection of extensive natural forest tracts to protect wild cacao in Bolivia.

  8. An Online Process Model of Second-Order Cultivation Effects: How Television Cultivates Materialism and Its Consequences for Life Satisfaction

    Science.gov (United States)

    Shrum, L. J.; Lee, Jaehoon; Burroughs, James E.; Rindfleisch, Aric

    2011-01-01

    Two studies investigated the interrelations among television viewing, materialism, and life satisfaction, and their underlying processes. Study 1 tested an online process model for television's cultivation of materialism by manipulating level of materialistic content. Viewing level influenced materialism, but only among participants who reported…

  9. Phylogeography of the wild and cultivated stimulant plant qat (Catha edulis, Celastraceae) in areas of historic cultivation1

    Science.gov (United States)

    Qat (Catha edulis, Celastraceae) is a woody plant species cultivated for its stimulant alkaloids. Qat is important to the economy and culture in large regions of Ethiopia, Kenya, and Yemen. Despite the importance of this species, the wild origins and dispersal of cultivars have only been described i...

  10. Establishment and Characterization of an Anaerobic Thermophilic (55 degrees C) Enrichment Culture Degrading Long-Chain Fatty Acids

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Ahring, Birgitte Kiær

    1995-01-01

    A thermophilic, long-chain fatty acid-oxidizing culture was enriched. Stearate was used as the substrate, and methane and carbon dioxide were the sole end products. Cultivation was possible only when a fed-batch system was used or with addition of activated carbon or bentonite. The enrichment...

  11. Biomass production of Lactobacillus plantarum LP02 isolated from ...

    African Journals Online (AJOL)

    The potentially hypocholesterolemic strain, designated PL02, of Lactobacillus plantarum, was isolated from infant feces. The aim of this study was to characterize and to cultivate this isolate for biomass production in a 5 L fermentor by batch or fed-batch fermentation. A modified medium composition without peptone was ...

  12. 21 CFR 573.920 - Selenium.

    Science.gov (United States)

    2010-04-01

    ... section, or as selenium yeast, as provided in paragraph (h) of this section. (c) It is added to feed as... months.” (h) Selenium yeast is a dried, non-viable yeast (Saccharomyces cerevisiae) cultivated in a fed-batch fermentation which provides incremental amounts of cane molasses and selenium salts in a manner...

  13. Substrate Channelling and Energetics of Saccharomyces cerevisiae ...

    African Journals Online (AJOL)

    Data collected during the high-cell-density cultivation of Saccharomyces cerevisiae DSM 2155 on glucose in a simulated five-phase feeding strategy of fed-batch process, executed on the Universal BIoprocess CONtrol (UBICON) system using 150L bioreactor over a period of 24h have been analysed. The consistency of the ...

  14. Fast Decline of Pythium zingiberum in Soil and Its Recolonization by Cultivating Susceptible Host Plants

    OpenAIRE

    ICHITANI, Takio; SHIMIZU, Tokiya

    1984-01-01

    This experiment demonstrates the fast decline of Pythium zingiberum in soil and its recolonization by cultivating mioga, susceptible host plant, and discusses growth and survival of the pathogen in the host rhizosphere in cultivated fields.

  15. Reducing the variability of antibiotic production in Streptomyces by cultivation in 24-square deepwell plates

    DEFF Research Database (Denmark)

    Siebenberg, S.; Bapat, Prashant Madhusudhan; Eliasson Lantz, Anna

    2010-01-01

    Highly reproducible production values of the aminocoumarin antibiotic novobiocin were achieved by cultivation of a heterologous Streptomyces producer strain in commercially available square deepwell plates consisting of 24 wells of 3 ml culture volume each. Between parallel cultivation batches...

  16. Greatly reduced phylogenetic structure in the cultivated potato clade of potatoes, Solanum section Petota

    Science.gov (United States)

    The species boundaries of wild and cultivated potatoes, Solanum section Petota, are controversial with most of the taxonomic problems in a clade containing cultivated potatoes. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these pr...

  17. Molecular comparison of cultivable protozoa from a pristine and a polycyclic aromatic hydrocarbon polluted site

    DEFF Research Database (Denmark)

    Lara, E; Berney, C; Ekelund, Flemming

    2007-01-01

    We compared the abundance and diversity of cultivable protozoa (flagellates and amoebae) in a polycyclic aromatic hydrocarbon (PAH) polluted soil and an unpolluted control, by isolating and cultivating clonal strains. The number of cultivable protozoa was higher in the polluted soil; however...

  18. Development of a domestic platn cultivation unit. Kateiyo saibai sochi no gaiyo

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, K. (The Tohoku Electric Power Co. Inc., Sendai (Japan))

    1993-06-15

    This paper describes development and operation evaluation on a domestic plant cultivating unit that can cultivate plants throughout a year by installing a prototype cultivating device effectively utilizing electric power, and controlling the cultivation environments. The prototype plant cultivating device uses trially an air cooling heat pump for general household use with high general-purpose applicability installed in a glass greenhouse with an area of about 10 m[sup 2], similar to those used by orchid lover club members. The device also uses commercially available humidifying and ventilating devices. No household horticultural facilities in cold district have ever used this kind of heat pump. Generally, cultivating environments in glass greenhouses are affected more easily by outside climate change as the greenhouse volume becomes smaller. For this reason, with this small-scale prototype cultivating device, orchids are cultivated to identify cultivating environments, and study technological development on controls over proper year-round cultivation and effective cultivation environments, as well as development and operation evaluation on household plant cultivation devices. 2 figs., 1 tab.

  19. Heterotrophic cultivation of microalgae for pigment production: A review.

    Science.gov (United States)

    Hu, Jianjun; Nagarajan, Dillirani; Zhang, Quanguo; Chang, Jo-Shu; Lee, Duu-Jong

    Pigments (mainly carotenoids) are important nutraceuticals known for their potent anti-oxidant activities and have been used extensively as high end health supplements. Microalgae are the most promising sources of natural carotenoids and are devoid of the toxic effects associated with synthetic derivatives. Compared to photoautotrophic cultivation, heterotrophic cultivation of microalgae in well-controlled bioreactors for pigments production has attracted much attention for commercial applications due to overcoming the difficulties associated with the supply of CO 2 and light, as well as avoiding the contamination problems and land requirements in open autotrophic culture systems. In this review, the heterotrophic metabolic potential of microalgae and their uses in pigment production are comprehensively described. Strategies to enhance pigment production under heterotrophic conditions are critically discussed and the challenges faced in heterotrophic pigment production with possible alternative solutions are presented. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Cultivation Of Microalgae (Chlorella vulgaris For Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Blinová Lenka

    2015-06-01

    Full Text Available Production of biofuel from renewable sources is considered to be one of the most sustainable alternatives to petroleum sourced fuels. Biofuels are also viable means of environmental and economic sustainability. Biofuels are divided into four generations, depending on the type of biomass used for biofuels production. At present, microalgae are presented as an ideal third generation biofuel feedstock because of their rapid growth rate. They also do not compete with food or feed crops, and can be produced on non-arable land. Cultivation conditions (temperature, pH, light, nutrient quantity and quality, salinity, aerating are the major factors that influence photosynthesis activity and behaviour of the microalgae growth rate. In this paper, we present an overview about the effect of cultivation conditions on microalgae growth.