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1.
An. acad. bras. ciênc ; 89(1): 57-63, Jan,-Mar. 2017. tab
Article in English | LILACS | ID: biblio-886625

ABSTRACT

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.


Subject(s)
Osmolar Concentration , Chemical Precipitation , Alcohols/chemistry , Glycoside Hydrolases/isolation & purification , Glycoside Hydrolases/chemistry , Reference Values , Salts/chemistry , Solvents/chemistry , Kluyveromyces/isolation & purification , Kluyveromyces/chemistry , Calcium Chloride/chemistry , Sodium Chloride/chemistry , Reproducibility of Results , Culture Media/chemistry
2.
Braz. j. microbiol ; 45(1): 294-301, 2014. ilus, tab
Article in English | LILACS | ID: lil-709490

ABSTRACT

Lipases produced by a newly isolated Sporidiobolus pararoseus strain have potential catalytic ability for esterification reactions. After production, the enzymatic extracts (conventional crude and precipitated, 'CC' and 'CP', and industrial crude and precipitated, 'IC' e 'IP') were partially characterized. The enzymes presented, in general, higher specificity for short chain alcohols and fatty acids. The precipitated extract showed a good thermal stability, higher than that for crude enzymatic extracts. The 'CC' and 'CP' enzymes presented high activities after exposure to pH 6.5 and 40 ºC. On the other hand, the 'IC' and 'IP' extracts kept their activities in a wide range of pH memory but presented preference for higher reaction temperatures. Preliminary studies of application of the crude lipase extract in the enzymatic production of geranyl propionate using geraniol and propionic acid as substrates in solvent-free system led to a reaction conversion of 42 ± 1.5%.


Subject(s)
Basidiomycota/enzymology , Lipase/isolation & purification , Lipase/metabolism , Alcohols/metabolism , Basidiomycota/growth & development , Enzyme Stability , Fatty Acids/metabolism , Hydrogen-Ion Concentration , Lipase/chemistry , Substrate Specificity , Temperature
3.
Braz. j. microbiol ; 43(4): 1490-1498, Oct.-Dec. 2012. ilus, graf, tab
Article in English | LILACS | ID: lil-665836

ABSTRACT

The lipase produced by a newly isolate Sporidiobolus pararoseus strain has potential catalysis ability for esterification reactions. In order to improve its synthetic activity, this work aimed at optimizing 'synthetic lipase' production by submerged fermentation of a conventional media based on peptone, yeast extract, NaCl and olive oil using experimental design technique. According to the results obtained in the first experimental design (2(4-1)), yeast extract and NaCl concentrations were tested to further optimization by response surface methodology. The maximum 'synthetic lipase' activity obtained was 26.9 U/mL in the optimized media (5.0, 6.8, 7.0 and 1.0% (wt/v) of peptone, yeast extract, NaCl and olive oil, respectively), representing a 6.36-fold increase compared to the initial medium. The time course of 'synthetic lipase' production in the optimized condition was evaluated in terms of synthetic activity, protease activity, biomass and total carbon and the maximum synthetic activity was observed during the stationary phase of growth.


Subject(s)
Base Sequence , Blastomyces/isolation & purification , Fermentation , Mitosporic Fungi/genetics , Mitosporic Fungi/isolation & purification , Yeasts/isolation & purification , Lipase/analysis , Lipase/isolation & purification , Enzyme Activation , Industrial Microbiology , Methodology as a Subject
4.
Braz. j. pharm. sci ; 48(3): 389-397, July-Sept. 2012. graf
Article in English | LILACS | ID: lil-653452

ABSTRACT

Rosmarinus officinalis (Rosemary) demonstrates antioxidant, antidepressant, diuretic, antinociceptive and antiulcerogenic activities. The present study was designed to examine the effects of the hydroalcoholic extract of R. officinalis on the memory of male mice. The behavioral tasks employed were social recognition (SR), the Morris water maze (MWM) and an inhibitory avoidance task (IA). The treatment with 150 and 300 mg/kg of R. officinalis improved the acquisition phase of learning of a new social memory in the SR task because a decrease was observed in the duration of social investigation. In the Morris water maze, no significant effect was observed on spatial memory when the groups were compared for the time spent in the correct quadrant. In the inhibitory avoidance task, the decrease in the step-down latencies in the test session indicate that 150 mg/kg of R. officinalis improved long-term memory when administered in the consolidation phase of learning. In conclusion, the present study showed that, the hydroalcoholic extract of R. officinalis at 150 and 300 mg/kg modulated the short- and long-term memories of mice, in a social recognition and inhibitory avoidance task, respectively. This modulator effect was shown to improve learning and memory processes.


Rosmarinus officinalis L. (Alecrim) possui atividade antioxidante, antidepressiva, diurética, antinociceptiva e antiulcerogênica. O presente estudo foi delineado para investigar o efeito do extrato hidroalcoólico de R. officinallis na memória de camundongos machos. Os modelos comportamentais utilizados foram a tarefa de reconhecimento social (RS), labirinto aquático de Morris (MWM) e esquiva inibitória (EI). O tratamento com 150 e 300mg/kg de R. officinallis, mostrou ter efeito positivo na aquisição de uma nova memória social, na tarefa de reconhecimento social, mostrando redução significativa do tempo de investigação social. No labirinto aquático de Morris, não foi visto efeito significativo na memória espacial, ao comparar o tempo desprendido no quadrante correto entre os diferentes tratamentos. Na esquiva inibitória a latência de descida da plataforma, observada na sessão teste, sugere que o tratamento com a dose 150 mg/kg de R. officinallis tem um efeito positivo na memória de longo prazo, quando administrada na fase de consolidação. Conclui-se que o extrato de R. officinalis nas doses de 150 e 300 mg/kg foi capaz de modular as memórias de curto e longo prazo dos roedores nas tarefas de reconhecimento social e esquiva inibitoria, respectivamente, e esse efeito modulatório melhorou os processos de aprendizado e memória.


Subject(s)
Mice , Rosmarinus/classification , Aromatic Extracts , Memory, Long-Term/classification , Spatial Memory/classification , Memory, Short-Term/classification , Rosmarinus/adverse effects
5.
Ciênc. agrotec., (Impr.) ; 32(5): 1568-1574, set.-out. 2008. tab
Article in Portuguese | LILACS | ID: lil-497008

ABSTRACT

Objetivou-se obter neste trabalho um corante natural (antocianina), na forma de pó a partir do bagaço de uva da cultivar "Isabel" (Vitis labrusca), onde foram realizados estudos de extração e encapsulamento. Empregou-se o método de extração por imersão mediante técnica de planejamento experimental, onde as variáveis avaliadas foram pH da solução de extração (1-2), volume de etanol (100-250 mL), tempo de extração (3-7 h) e temperatura de extração (15-35ºC). A concentração máxima de antocianinas totais obtidas foi de 300 mg/100 g de bagaço de uva (umidade 5 por cento) nos níveis inferiores de pH (1,0) e tempo (3 horas) e superiores de temperatura (35ºC) e volume de etanol (250 mL). Os extratos foram secos por atomização. A melhor condição para o encapsulamento e a secagem foi quando utilizaram-se proporções iguais de maltodextrina e goma arábica.


This work had the aim of obtaining a natural pigment (anthocyanin) at powder form from 'Isabel' grape bagasse (Vitis labrusca), studying the extraction and encapsulating steps one applied the method of extraction by immersion by experimental design technique, when the factors investigated were pH of the extraction solution (1-2), volume of ethanol (100-250 mL), extraction time (3-7 h) and extraction temperature (15-35 °C). The maximum concentration of total anthocyanin was 300 mg/100g of grape bagasse (5 percent moisture) at the lower levels of pH (1.0) and time (3 h), and at upper levels of temperature (35ºC) and amount of ethanol (250 mL). The extracts were dried by a spray process. The best condition for encapsulating and drying was obtained when equal amounts of maltodextrin and Arabic gum were used.

6.
Ciênc. agrotec., (Impr.) ; 31(1): 177-183, jan.-fev. 2007. ilus, tab
Article in Portuguese | LILACS | ID: lil-454334

ABSTRACT

Com este trabalho, avaliou-se a produção de biopolímero sintetizado por Sphingomonas capsulata ATCC 14666, utilizando-se os meios industriais melaço bruto e pré-tratado e resíduo de proteína texturizada de soja (PTS). Foram testadas diferentes concentrações de meios industriais (2,66, 4, 6 e 8 por cento), cujas condições de fermentação utilizadas foram 28° ± 2°C, 208 rpm, 72 h. Os ensaios foram realizados em triplicata e os resultados foram avaliados estatisticamente mediante o teste de Tukey. As melhores produtividades foram obtidas para melaço pré-tratado 8 por cento (0,290 gL-1h-1), seguida de extrato aquoso de resíduo de PTS 6 por cento (0,240 gL-1h-1) e melaço bruto 8 por cento (0,190 gL-1h-1). A qualidade reológica das gomas foi demonstrada através da leitura de viscosidade aparente de soluções aquosas e salinas a 25 e 60°C.


This work studied the biopolymer production by Sphingomonas capsulata ATCC 14666 using industrial raw material and pretreated molasses and aqueous extract of textured soy protein (TSP). Different concentrations of industrial media (2.66, 4, 6 and 8 w/t percent) were evaluated at 28° ± 2°C, 208rpm, 72h, were the fermentation conditions utilized. Triplicate assays were conducted and Tukey's test was used. The highest productivity were obtained for 8 percent of pretreated molasses (0,290 gL-1h-1), 6 percent of aqueous extract of TSP (0,240 gL-1h-1) and 8 percent raw molasses (0,190 gL-1h-1), respectively. The rheological behavior of aqueous and saline (NaCl and CaCl2 3 percent wt/v) solutions of biopolymers were investigated by apparent viscosity analysis at 25 and 60°C.

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