997 resultados para biotechnological production


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Lovastatin is a potent hypercholesterolemic drug used for lowering blood cholesterol. It acts by competitively inhibiting the enzyme, 3-hydroxy-3-methylglutaryl coenzyme A reductase involved in the biosynthesis of cholesterol. It is produced by a variety of filamentous fungi including Penicillium species, Monascus ruber and Aspergillus terreus as a secondary metabolite. Production of lovastatin by biotechnology decreases the production cost compared to costs of chemical synthesis. In recent years, lovastatin has also been reported as a potential therapeutic agent for the treatment of various types of tumors and also play a tremendous role in the regulation of the inflammatory and immune response, coagulation process, bone turnover, neovascularization, vascular tone, and arterial pressure. This review focus on the structure, biosynthesis, biotechnological production and biomedical applications of lovastatin.

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This paper describes a feasibility study of a for lactic acid production integrated with are treatment of wastewater from an industrial starch plant. Rhizopus oryzae two strains, Rhizopus arrhizus and Rhizopus oligosporus were tested with respect to their capability to carry out simultaneous saccharification and fermentation to lactic acid using potato wastewater. Rhizopus arrhizus DAR 36017 was identified as a suitable strain that demonstrated a high capacity for starch saccharification and lactic acid synthesis. The optimal conditions, in terms of pH, temperature and starch concentration, for lactic acid production were determined. The selected fungal strain grew well in a pH range from 3.0 to 7.0. The addition of CaCO(3)10 g dm(-3) maintained the pH at 5.0-6.0 and significantly enhanced lactic acid production. Kinetic study revealed that almost complete starch saccharification and a lactic acid yield of 450g kg(-1) could be achieved in 20 h and 28 h cultivation, respectively. The maximum lactic acid production 21 g dm(-3) and mycelial biomass (1.7 g dm(-3)) were obtained at 30degreesC. Besides the multiple bioproducts, total removal of suspended solids and 90% reduction of COD were achieved in a single no-aseptic operation. (C) 2003 Society of Chemical Industry.

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The present study sought biotensoactive production from soybean oil fry waste using Pseudomonas aeruginosa ATCC 10145 and Pseudomonas aeruginosa isolated from the soil of a petroleum station having undergone gasoline and diesel oil spills. The results of the experiments were analyzed using a complete factorial experimental design, investigating the concentration of soybean oil waste, ammonia sulfate and residual brewery yeast. Assays were performed in 250-mL Erlenmeyer beakers containing 50 mL of production medium, maintained on a rotary shaker at 200 rpm and a temperature of 30±1 °C for a 48-hour fermentation period. Biosurfactant production was monitored through the determination of rhamnose, surface tension and emulsification activity. The Pseudomonas aeruginosa ATCC 10145 strain and isolated Pseudomonas aeruginosa were able to reduce the surface tension of the initial mexlium from 61 mN/m to 32.5 mN/m and 30.0 mN/m as well as produce rhamnose at concentrations of 1.96 and 2.89 g/L with emulsification indices of 96% and 100%, respectively.

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L(+) Lactic acid fermentation was studied by Lactobacillus rhamnosus sp. under the effects of pH control and a lowcost nutritional medium (sugarcane juice and corn steep liquor-CSL). Central composite design (CCD) was employed to determine maximum lactic acid production at optimum values for process variables and a satisfactory fit model was realized. Statistical analysis of the results showed that the linear and quadratic terms of two variables (sugarcane juice and pH) had significant effects. The interactions between the three variables were found to contribute to the response at a significant level. A second-order polynomial regression model estimated that the maximum lactic acid production of 86.36 g/L was obtained when the optimum values of sucrose, CSL and pH were 112.65 g/L, 29.88 g/L and 6.2, respectively. Verification of the optimization showed that L(+) lactic acid production was of 85.06 g/L. Under these conditions, Y P/S and Q P values of 0.85 g/g and 1.77 g/Lh, respectively, were obtained after 48 h fermentation, with a maximal productivity of 2.2 g/L h at 30 h of process. © 2010 de Lima CJB, et al.

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Although the biopolymer poly-(3-hydroxybutyrate), P[3HB], presents physicochemical properties that make it an alternative material to conventional plastics, its biotechnological production is quite expensive. As carbon substrates contribute greatly to P[3HB] production cost, the utilization of a cheaper carbon substrate and less demanding micro-organisms should decrease its cost. In the present study a 23 factorial experimental design was applied, aiming to evaluate the effects of using hydrolysed corn starch (HCS) and soybean oil (SBO) as carbon substrates, and cheese whey (CW) supplementation in the mineral medium (MM) on the responses, cell dried weigh (DCW), percentage P[3HB] and mass P[3HB] by recombinant Escherichia coli strains JM101 and DH10B, containing the P[3HB] synthase genes from Cupriavidus necator (ex-Ralstonia eutropha). The analysis of effects indicated that the substrates and the supplement and their interactions had positive effect on CDW. Statistically generated equations showed that, at the highest concentrations of HCS, SO and CW, theoretically it should be possible to produce about 2 g L(1) DCW, accumulating 50% P[3HB], in both strains. To complement this study, the strain that presented the best results was cultivated in MM added to HCS, SBO and CW ( in best composition observed) and complex medium (CM) to compare the obtained P[3HB] in terms of physicochemical parameters. The obtained results showed that the P[3HB] production in MM (1.29 g L(-1)) was approximately 20% lower than in CM (1.63 g L(-1)); however, this difference can be compensated by the lower cost of the MM achieved by the use of cheap renewable carbon sources. Moreover, using differential scanning calorimetry and thermogravimetry analyses, it was observed that the polymer produced in MM was the one which presented physicochemical properties (Tg and Tf) that were more similar to those found in the literature for P[3HB].

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Petiveria alliacea L. pertence à família Phytolaccacceae e é conhecida popularmente como guiné ou amansa-senhor, entre outros nomes. Tem sido muito utilizada na medicina popular como agente terapêutico, devido à diversas propriedades farmacológicas. Estudos fitoquímicos têm contribuído para a descoberta de grande variedade de substâncias biologicamente ativas produzidas em diferentes partes da planta (saponinas, alcalóides, flavonóides, sulfetos, taninos, cumarinas, entre outros). A análise química da raiz tem revelado grande quantidade de derivados sulfurados, principalmente o dibenzil trissulfeto (DTS), com atividade antifúngica, antibacteriana, antioxidante e anticancerígena. Visando avaliar a produção biotecnológica do DTS, o presente trabalho teve como objetivo, otimizar a cultura de novas linhagens de calos, células em suspensão e embriões somáticos, a partir de plantas de P. alliacea L. mantidas in vitro, com o monitoramento da capacidade biossintética das culturas. Os resultados mostraram que a produção de calos friáveis foi possível em explantes foliares inoculados em meio MS suplementado com PIC ou 2,4-D. Além da resposta calogênica, foi observada a produção de estruturas globulares caracterizadas como embriões somáticos. A ocorrência de embriogênese somática direta foi confirmada através da análise histológica do processo regenerativo. A indução de embriões somáticos gerou um processo de embriogênese secundária altamente repetitivo até 150 dias de cultura e conversão a plantas em freqüência de 5%. Em relação à cultura de células em suspensão a partir dos calos friáveis, observou-se uma diminuição do crescimento celular ao longo das subculturas. As culturas em suspensão originadas de tecido embriogênico secundário continuaram o processo repetitivo em meio líquido e apresentaram conversão a plantas em taxas mais baixas que as obtidas em meio sólido. A obtenção de plantas completas a partir dos embriões somáticos demonstrou a possibilidade de utilização desse sistema para a micropropagação dessa espécie. O monitoramento fitoquímico dos sistemas de cultura in vitro e plantas de campo mantidas em casa de vegetação durante 02 anos apresentou diferenças significativas, confirmando que a cultura de tecidos pode alterar as rotas metabólicas. A cromatografia gasosa acoplada à espectrometria de massas realizada com extrato em diclorometano de embriões secos e hexânico de embriões frescos e raízes secas de plantas provenientes de embriões somáticos, demonstrou a presença do DTS, constituindo, portanto, sistemas in vitro importantes para a modulação desta substância.

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Aims: To study the biotechnological production of lipids containing rich amounts of the medically and nutritionally important c-linolenic acid (GLA), during cultivation of the Zygomycetes Thamnidium elegans, on mixtures of glucose and xylose, abundant sugars of lignocellulosic biomass. Methods and Results: Glucose and xylose were utilized as carbon sources, solely or in mixtures, under nitrogen-limited conditions, in batch-flask or bioreactor cultures. On glucose, T. elegans produced 31.9 g/L of biomass containing 15.0 g/L lipid with significantly high GLA content (1014 mg/L). Xylose was proved to be an adequate substrate for growth and lipid production. Additionally, xylitol secretion occurred when xylose was utilized as carbon source, solely or in mixtures with glucose. Batch-bioreactor trials on glucose yielded satisfactory lipid production, with rapid substrate consumption rates. Analysis of intracellular lipids showed that the highest GLA content was observed in early stationary growth phase, while the phospholipid fraction was the most unsaturated fraction of T. elegans. Conclusions: Thamnidium elegans represents a promising fungus for the successful valorization of sugar-based lignocellulosic residues into microbial lipids of high nutritional and pharmaceutical interest.

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A protocol to produce large amounts of bioactive homogeneous human interferon β1 expressed in Escherichia coli was developed. Human interferon β1 ser17 gene was constructed, cloned and subcloned, and the recombinant protein expressed in E. coli cells. Solubilization of recombinant human interferon β1 ser17 (rhIFN-β1 ser17) was accomplished by employing a brief shift to high alkaline pH in the presence of non-ionic detergent. The recombinant protein was purifi ed by three chromatographic steps. N-terminal amino acid sequencing and mass spectrometry analysis provided experimental evidence for the identity of the recombinant protein. Reverse phase liquid chromatography demonstrated that the content of deamidates and sulphoxides was similar to a commercial standard. Size exclusion chromatography demonstrated the absence of high molecular mass aggregates and dimers. The protocol represents an effi cient and high-yield method to obtain bioactive homogeneous monomeric rhIFN-β1 ser17 protein. It may thus represent an important step towards scaling up for rhIFN-β1 ser17 large-scale production. © 2010 Villela AD, et al.

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Invertase from Saccharomyces cerevisiae was immobilized on agarose beads, activated with various groups (glyoxyl, MANAE or glutaraldehyde), and on some commercial epoxy supports (Eupergit and Sepabeads). Very active and stable invertase derivatives were produced by the adsorption of the enzyme on MANAE-agarose, MANAE-agarose treated with glutaraldhyde and glutaraldehyde-agarose supports. At pH 5.0, these derivatives retained full activity after 24h at 40°C and 50 °C. When assayed at 40°C and 50°C, with the pH adjusted to 7.0, the invertase-MANAE-agarose derivative treated with glutaraldehyde retained 80% of the initial activity. Recovered activities of the derivatives produced with MANAE, MANAE treated with glutaraldehyde and glutaraldehyde alone were 73.5%, 44.4% and 36.8%, respectively. These three preparations were successfully employed to produce glucose and fructose in 3 cycles of sucrose hydrolysis.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The screening. biomass growth of lipase-producing fungus isolated from different sources and available at URM (University Recife Mycologia). as well as, the immobilization and utilization of the whole cells for the transesterification of babassu oil were investigated. Rhizopus oryzae (URM 3231, 4692), Mucor circinelloides (URM 4140, 4182) and Penicillium citrinum URM 4216 were considered to be good intracellular lipase producers whereas those from Mucor hiemalis URM 4144 and Mucor piriformis URM 4145 were weaker. Fungi biomass containing high lipase activities was immobilized on different biomass support particles (BSPs) and with the exception of Penicillium citrinum URM 4216 all the other fungi strains exhibited high lipase activity (20-50 Ug(-1)) when immobilized in situ using polyurethane foam particles. Transesterification activities of the immobilized whole cells were evaluated in the ethanolysis reaction with babassu oil and the highest performance was attained by M. circinelloides URM 4182 giving 83.22 +/- 3.68% ester yield in less than 96 h reaction. The biocatalyst operational stability was also assessed and an inactivation profile was found to follow the Arrhenius model, revealing values of 26 days and 2.6 x 10(-2)day(-1), for half-life and a deactivation coefficient, respectively. The purified product (biodiesel) exhibited viscosity (6.63 cSt) close to the value to attend specifications by the ASTM 06751 to be used as biofuel. Results are favorable compared with data already reported in the literature and demonstrated that M. circinelloides URM 4182 whole cells is a cheaper biocatalyst that can be used in the biodiesel synthesis. (C) 2012 Elsevier B.V. All rights reserved.

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Durch globale Expressionsprofil-Analysen auf Transkriptom-, Proteom- oder Metabolom-Ebene können biotechnologische Produktionsprozesse besser verstanden und die Erkenntnisse für die zielgerichtete, rationale Optimierung von Expressionssystemen genutzt werden. In der vorliegenden Arbeit wurde die Überexpression einer Glukose-Dehydrogenase (EC 1.1.5.2), die von der Roche Diagnostics GmbH für die diagnostische Anwendung optimiert worden war, in Escherichia coli untersucht. Die Enzymvariante unterscheidet sich in sieben ihrer 455 Aminosäuren vom Wildtyp-Enzym und wird im sonst isogenen Wirt-/Vektor-System in signifikant geringeren Mengen (Faktor 5) gebildet. Das prokaryontische Expressionssystem wurde auf Proteom-Ebene charakterisiert. Die 2-dimensionale differenzielle Gelelektrophorese (DIGE) wurde zuvor unter statistischen Aspekten untersucht. Unter Berücksichtigung von technischen und biologischen Variationen, falsch-positiven (α-) und falsch-negativen (β-) Fehlern sowie einem daraus abgeleiteten Versuchsdesign konnten Expressionsunterschiede als signifikant quantifiziert werden, wenn sie um den Faktor ≥ 1,4 differierten. Durch eine Hauptkomponenten-Analyse wurde gezeigt, dass die DIGE-Technologie für die Expressionsprofil-Analyse des Modellsystems geeignet ist. Der Expressionsstamm für die Enzymvariante zeichnete sich durch eine höhere Variabilität an Enzymen für den Zuckerabbau und die Nukleinsäure-Synthese aus. Im Expressionssystem für das Wildtyp-Enzym wurde eine unerwartet erhöhte Plasmidkopienzahl nachgewiesen. Als potenzieller Engpass in der Expression der rekombinanten Glukose-Dehydrogenase wurde die Löslichkeitsvermittlung identifiziert. Im Expressionsstamm für das Wildtyp-Enzym wurden viele Proteine für die Biogenese der äußeren Membran verstärkt exprimiert. Als Folge dessen wurde ein sog. envelope stress ausgelöst und die Zellen gingen in die stationäre Wuchsphase über. Die Ergebnisse der Proteomanalyse wurden weiterführend dazu genutzt, die Produktionsleistung für die Enzymvariante zu verbessern. Durch den Austausch des Replikationsursprungs im Expressionsvektor wurde die Plasmidkopienzahl erhöht und die zelluläre Expressionsleistung für die diagnostisch interessantere Enzymvariante um Faktor 7 - 9 gesteigert. Um die Löslichkeitsvermittlung während der Expression zu verbessern, wurde die Plasmidkopienzahl gesenkt und die Coexpression von Chaperonen initiiert. Die Ausbeuten aktiver Glukose-Dehydrogenase wurden durch die Renaturierung inaktiven Produkts aus dem optimierten Expressionssystem insgesamt um einen Faktor von 4,5 erhöht. Somit führte im Rahmen dieser Arbeit eine proteombasierte Expressionsprofil-Analyse zur zielgerichteten, rationalen Expressionsoptimierung eines prokaryontischen Modellsystems.

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Background: Several materials have been used for tissue engineering purposes, since the ideal matrix depends on the desired tissue. Silk biomaterials have come to focus due to their great mechanical properties. As untreated silkworm silk has been found to be quite immunogenic, an alternative could be spider silk. Not only does it own unique mechanical properties, its biocompatibility has been shown already in vivo. In our study, we used native spider dragline silk which is known as the strongest fibre in nature. Methodology/Principal Findings: Steel frames were originally designed and manufactured and woven with spider silk, harvesting dragline silk directly out of the animal. After sterilization, scaffolds were seeded with fibroblasts to analyse cell proliferation and adhesion. Analysis of cell morphology and actin filament alignment clearly revealed adherence. Proliferation was measured by cell count as well as determination of relative fluorescence each after 1, 2, 3, and 5 days. Cell counts for native spider silk were also compared with those for trypsin-digested spider silk. Spider silk specimens displayed less proliferation than collagen-and fibronectin-coated cover slips, enzymatic treatment reduced adhesion and proliferation rates tendentially though not significantly. Nevertheless, proliferation could be proven with high significance (p<0.01). Conclusion/Significance: Native spider silk does not require any modification to its application as a biomaterial that can rival any artificial material in terms of cell growth promoting properties. We could show adhesion mechanics on intracellular level. Additionally, proliferation kinetics were higher than in enzymatically digested controls, indicating that spider silk does not require modification. Recent findings concerning reduction of cell proliferation after exposure could not be met. As biotechnological production of the hierarchical composition of native spider silk fibres is still a challenge, our study has a pioneer role in researching cellular mechanics on native spider silk fibres.

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O interesse na produção de astaxantina de fontes naturais vem aumentando significativamente, devido principalmente à sua capacidade como potente agente antioxidante. Na obtenção da astaxantina por via biotecnológica, a microalga Haematococcus pluvialis é um dos micro-organismos industrialmente mais interessantes. Entretanto, como a maioria dos carotenoides, a astaxantina é uma molécula altamente insaturada que pode ser facilmente degradada por processos térmicos. Em função desta instabilidade, uma possibilidade que se abre, a fim de proteger sua atividade biológica de fatores ambientais e reforçar a sua estabilidade física, é o encapsulamento. Neste sentido, este trabalho vem contribuir em inovações relacionadas ao desenvolvimento de tecnologia para ruptura celular, extração e nanoencapsulamento de astaxantina produzida por via biotecnológica, mais especificamente de astaxantina obtida através do cultivo de H. pluvialis. Neste estudo, os cultivos foram realizados em meio BBM e acetato de sódio e conduzidos a temperatura constante de 25±1 ºC em fotobiorreatores de 1 L com aeração por borbulhamento de ar de 300 mL.min-1 , agitação manual diária e sob iluminância constante de 444 µmol fótons.m-2 s -1 durante 15 dias, sendo inoculados com suspensão de microalgas previamente preparada, na proporção de 10%, e pH ajustado em 7,0. A biomassa foi recuperada dos cultivos por centrifugação e seca a 35 °C por 48 h. Em seguida, foram empregadas diferentes técnicas de ruptura celular (química, mecânica e enzimática). Após a ruptura, foi realizada a extração dos carotenoides e a quantificação dos carotenoides totais (µg.g-1 ) e da extratibilidade (%). Entre os solventes testados no método de ruptura química, o diclorometano foi o selecionado para a extração dos pigmentos carotenoides. Dentre as técnicas mecânicas de ruptura celular, a maceração da biomassa congelada com terra diatomácea resultou na maior extratibilidade e carotenoides totais (66,01% e 972,35 μg.g-1 ). A melhor condição de lise da parede celular de H. pluvialis, utilizando o preparado enzimático Glucanex® , ocorreu em pH do meio reacional de 4,5 a 55 ºC, com atividade inicial de β-1,3-glucanase de 0,6 U.mL-1 e um tempo de reação de 30 min, alcançando-se 17,73% de atividade lítica relativa. Nestas condições, com a reação enzimática assistida por ultrassom sem congelamento prévio da biomassa, atingiu-se 83,90% e 1235,89 µg.g -1 , respectivamente, para extratibilidade e carotenoides totais. Dentre as técnicas combinadas testadas, a maceração com terra diatomácea associada à lise enzimática apresentou valores de extratibilidade e carotenoides totais de, respectivamente, 93,83% e 1382,12 µg.g-1 . No encapsulamento do extrato contendo astaxantina obtido por lise enzimática associada por ultrassom, envolvendo a coprecipitação com PHBV (poli(3-hidroxibutirato-cohidroxivalerato)) em fluidos supercríticos, o aumento da pressão tendeu a reduzir o diâmetro da partícula formada, enquanto que o aumento da relação biomassa contendo astaxantina:diclorometano usada na etapa de extração incrementou o percentual de encapsulamento e a eficiência de encapsulamento para ambas pressões testadas (80 e 100 bar). Os maiores valores de percentual de encapsulamento (17,06%) e eficiência de encapsulamento (51,21%) foram obtidos nas condições de 80 bar e relação biomassa:diclorometano de 10 mg.mL -1 . Nestas condições, o diâmetro médio de partícula foi de 0,228 µm. Com base nos resultados obtidos, técnicas para a obtenção de astaxantina de H. pluvialis e seu encapsulamento foram desenvolvidas com sucesso, podendo ser extendidas a outros produtos intracelulares de microalgas.

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Taro (Colocasia esculenta L. Schott) is an important crop worldwide but is of particular significance in many Pacific Island countries where it forms part of the staple diet and serves as an export commodity. Escalating pest and disease problems are jeopardizing taro production with serious implications to food security and trade. Biotechnological approaches to addressing pest and disease problems, such as somatic embryogenesis and transgenesis, are potentially viable options. However, despite biotechnological advancements in higher profile agronomic crops, such progress in relation to Colocasia esculenta var. esculenta has been slow. This paper reviews taro biology, highlights the cultural and economic significance of taro in Pacific Island countries and discusses the progress made towards the molecular breeding of this important crop to date.