Sample records for lipases

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Lipases de látex vegetais: propriedades e aplicações industriais/ Plant lipases from latex: properties and industrial applications

Paques, Fernanda Wiermann; Macedo, Gabriela Alves

Resumo em inglês Biocatalysts have innumerous advantages with respect to classical chemical processes, such as high specificity. Lipases (EC are biocatalysts with large application in synthesis and hydrolysis reactions of triacylglycerols. The search for new sources of lipases has been intensified in the last years due to the high cost of microbial and animal lipases, wich restricts their use on an industrial scale. Lipases obtained from the latex of Carica papaya, Carica pentago (mais) na, Euphorbia characias, E. wulfenii, known for their proteolytic properties, are a good alternative source. In this review, we describe the well-known sources of vegetal lipases extracted from the latex and present some of their industrial applications.

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Aplicação de lipases no tratamento de águas residuárias com elevados teores de lipídeos/ Application of lipases for wastewater treatment containing high levels of lipids

Mendes, Adriano Aguiar; Castro, Heizir Ferreira de; Pereira, Ernandes Benedito; Furigo Júnior, Agenor

Resumo em inglês The process of anaerobic digestion has been greatly developed during the last decades for the treatment of wastewater from food industries as for example, wastewaters from sugar and starch manufacturing and from breweries. However, for wastewaters which contain high amounts of fats and proteins, such as those from slaughterhouses and dairies, anaerobic digestion was found to be troublesome, due to the potential of sludge flotation, the formation of scum layers of lipids a (mais) t the surface of the reactor, which are not digested and the toxicity of the intermediate compounds (long chain fatty acids) generated during the anaerobic digestion of the wastewater. The addition of hydrolytic enzymes, such as lipases prior to the anaerobic digestion can minimize these problems. In this work, this strategy is reviewed and the technical issues that must be considered in determining its feasibility are discussed.

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Aplicação de lipases microbianas na obtenção de concentrados de ácidos graxos poliinsaturados/ Application of microbial lipases to concentrate polyunsaturated fatty acids

Carvalho, Patrícia de Oliveira; Campos, Paula Renata Bueno; Noffs, Maximiliano D'Addio; Oliveira, Joaquim Gilberto de; Shimizu, Mário Tsunezi; Silva, Daniela Martins da

Resumo em inglês Several polyunsaturated fatty acids (PUFA) belonging to the ômega 6 series, such as cis-6,9,12 gamma-linolenic acid, as well as those of the ômega 3 series, such as cis-5,8,11,14,17-eicosapentaenoic acid and cis-4,7,10,13,16,19-docosahexaenoic acid are of considerable interest due to their nutritional and therapeutic properties. Methods used for the concentration of PUFA from natural sources include urea adduct formation, solvent winterization, supercritical fluid extra (mais) ction and lipase-catalyzed reaction. Lipases are known to have little reactivity on PUFA and these acids can be enriched by selective hydrolysis, direct esterification of glycerol with PUFA and interesterification. Since lipase reactions are advantageous with respect to fatty acid, positional specificities and mild incubation condition, these enzymes are considered to be suitable for the production of PUFA concentrates for medical purposes.

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O emprego de lipases como agentes de resolução cinética de enantiômeros em síntese orgânica: aspectos gerais sobre a influência do solvente/ The use of lipases as agents of kinetic resolution of enantiomers in organic synthesis: general aspects of solvent's influence

Costa, Valentim Emilio Uberti; Amorim, Hermes Luís Neubauer de

Resumo em inglês In organic synthesis, lipases are the most frequently used biocatalysts. They are efficient stereoselective catalysts in the kinetic resolution of a wide variety of chiral compounds. The discovery that enzymes possess catalytic activity in organic solvents has made it possible to address the question of reaction medium influence on enzymatic specificity. Perhaps the most exciting and significant development in this emerging area is the discovery that enzyme specificity, i (mais) n particular enantioselectivity, can be affected by changing from one organic solvent to another. This article discusses the scope and possible mechanistic models of this phenomenon in hydrolases, specially lipases, as well as directions of future research in the area.

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Imobilização de lipases produzidas por fermentação em estado sólido utilizando Penicillium verrucosum em suportes hidrofóbicos/ Immobilization of lipases produced by solid state fermentation from Penicillium verrucosum on hydrophobic supports

Menoncin, Silvana; Domingues, Natalia Molossi; Freire, Denise Maria Guimarães; Oliveira, José Vladimir; Di Luccio, Marco; Treichel, Helen; Oliveira, Débora de

Resumo em português O principal interesse em imobilizar uma enzima é obter um biocatalisador com atividade e estabilidade que não sejam afetadas durante o processo, em comparação à sua forma livre. Aliado ao potencial biotecnológico que as lipases apresentam, a aplicação destas em nível industrial requer a investigação de técnicas viáveis para reutilização e aumento da estabilidade, conferindo relevância aos processos de imobilização. Neste trabalho investigou-se a imobiliz (mais) ação da lipase produzida por fermentação em estado sólido utilizando Penicillium verrucosum em dois suportes hidrofóbicos; Accurel EP 1000 e Carvão Ativo. Para a imobilização das lipases foi adicionado 1 g de suporte a 50 mL de uma solução enzimática, estes permaneceram em contato por 2 horas em banho de gelo. Depois de decorrido este tempo, a solução foi filtrada e a enzima imobilizada colocada em dessecador por 48 horas e então feita a medida da atividade lipásica, proteína e cálculo da atividade específica. Através dos resultados obtidos, verificou-se que lipase imobilizada em carvão ativo apresentou valores de atividade específica superiores aos obtidos quando da utilização de Accurel EP 1000 como suporte. Utilizando carvão ativo como suporte, a atividade específica foi de 1533422,5 U/mg de proteína, rendimento de 30,4% e retenção de 382,5%. Resumo em inglês The major interest in the immobilization of enzymes is obtaining a biocatalyst with activity and stability that are not affected during the process when compared to the free enzyme. The application of lipases in industries requires the study of techniques suitable for reuse and stability increase such as immobilization strategies. This work studied the immobilization of lipases produced by solid state fermentation from Penicillium verrucosum using two hydrophobic supports (mais) : Accurel EP 1000 and activated carbon. For the lipase immobilization, 1 g of support was added to 50 mL of an enzyme solution and kept for 2 hour in an ice bath. The solution was then filtered and the immobilized enzyme was stored in a dissecator for 48 hour before the assays for lipase activity, protein, and specific lipase activity. The results showed that the lipase immobilized in activated carbon presented higher specific activity than the lipase immobilized in Accurel EP 1000. The use of activated carbon as support led to a specific activity of 1.5 × 10(6) U/mg of protein, yield of 30.42%, and retention of 382.516%.

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Potencial de biocatálise enantiosseletiva de lipases microbianas/ Potential of enantioselective biocatalysis by microbial lipases

Carvalho, Patrícia de O.; Calafatti, Silvana Ap.; Marassi, Maurício; Silva, Daniela M. da; Contesini, Fabiano J.; Bizaco, Renato; Macedo, Gabriela Alves

Resumo em inglês Microbial lipases have a great potential for commercial applications due to their stability, selectivity and broad substrate specificity because many non-natural acids, alcohols or amines can be used as the substrate. Three microbial lipases isolated from Brazilian soil samples (Aspergillus niger; Geotrichum candidum; Penicillium solitum) were compared in terms of their stability and as biocatalysts in the enantioselective esterification using racemic substrates in organi (mais) c medium. The lipase from Aspergillus niger showed the highest activity (18.2 U/mL) and was highly thermostable, retaining 90% and 60% activity at 50 ºC and 60 ºC after 1 hour, respectively. In organic medium, this lipase provided the best results in terms of enantiomeric excess of the (S)-active acid (ee = 6.1%) and conversion value (c = 20%) in the esterification of (R,S)-ibuprofen with 1-propanol in isooctane. The esterification reaction of the racemic mixture of (R,S)-2-octanol with decanoic acid proceeded with high enantioselectivity when lipase from Aspergillus niger (E = 13.2) and commercial lipase from Candida antarctica (E = 20) were employed.

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Síntese enzimática de butirato de isoamila empregando lipases microbianas comerciais/ Enzymatic synthesis isoamyl butyrate employing commercial microbial lipases

Aragão, Vitor Cardoso; Anschau, Andréia; Porciuncula, Barbara Daniele Almeida; Thiesen, Cleidi; Kalil, Susana Juliano; Burkert, Carlos André Veiga; Burkert, Janaína Fernandes de Medeiros

Resumo em inglês Isoamyl butyrate production was investigated using free and immobilized lipases by esterification of butyric acid with isoamyl alcohol in a solvent-free system and in an organic media. Among the enzymes studied, Lipozyme TL IM was found to be the most active catalyst in n-hexane as a solvent. The effects of different solvents and the amount of water added on conversion rates were studied. A maximum conversion yield of 80% in n-hexano at 48 h was obtained under the followi (mais) ng conditions: 3 g L-1 of Lipozyme TL IM, 30 ºC, 180 rpm of agitation, isoamyl alcohol to butyric acid molar ratio of 1:1 and acid substrate concentration of 0.06 M.

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Imobilização de lipases em filme de caseinato de sódio/glicerol: aplicação na síntese de ésteres/ Lipase immobilization in sodium caseinate/glycerol film: application in ester synthesis

Sebrão, Damianni; Silva, Vanessa Dutra; Nascimento, Maria da Graça; Moreira, Marcelo Alves

Resumo em inglês Lipases from different sources were immobilized in sodium caseinate/glycerol film and used in the esterification reactions of aliphatic acids with alcohols in the presence of organic solvents. Lipases from Pseudomonas sp and Rhizopus oryzae were selected and the influence of several parameters was analyzed, including: lipase loading, organic solvent polarity, reaction temperature, chain length of alcohol and acid and enzyme/support reuse. For comparison, free enzymes were used under similar experimental conditions.

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Avaliação da produção de lipases por diferentes cepas de microrganismos isolados em efluentes de laticínios por fermentação submersa/ Evaluation of lipase production using different strains of microorganisms isolated from dairy effluent through submerged fermentation

Roveda, Mirela; Hemkemeier, Marcelo; Colla, Luciane Maria

Resumo em português A produção enzimática é um dos campos mais promissores dentro das tecnologias para a síntese de compostos de alto valor agregado, estando em constante crescimento pela grande capacidade dos microrganismos de realizarem transformações químicas. As enzimas produzidas por processos fermentativos têm sido utilizadas para o controle ambiental. Muitas destas enzimas podem ser produzidas a partir de resíduos industriais, diminuindo os custos de produção. As lipases s (mais) ão enzimas que catalisam a hidrólise de triglicerídeos em glicerídeos e ácidos graxos. As lipases vêm sendo utilizadas na redução da concentração dos lipídios contidos nos efluentes, promovendo a hidrólise dos óleos e gorduras presentes. Objetivou-se avaliar a produção de lipases por fungos isolados a partir de efluentes de laticínios. Foram isolados 21 fungos, pertencentes aos gêneros Penicillium, Aspergillus, Trichoderma e Fusarium. Na etapa de seleção, 9 fungos foram selecionados devido à capacidade de crescimento em meio contendo azeite de oliva como substrato. Na fermentação submersa, os fungos E9 (Aspergillus), E21 (Aspergillus) e E20 (Penicillium) foram os que apresentaram as maiores atividades enzimáticas, de 1,250 a 2,250 U, utilizando-se como meio de cultivo o efluente coletado na saída do equalizador do sistema de tratamento de efluente. Resumo em inglês Enzymatic production is one of the most promising fields within technologies for the synthesis of high added value compounds, given their constant growth due to the great capacity of microorganisms to carry out chemical transformations. The enzymes produced from fermentation processes have been used for environmental control. Many of these enzymes can be produced from industrial residues, reducing the production cost. Lipases are a group of enzymes that catalyze hydrolysi (mais) s of triglycerides to glycerides and fatty acids. Lipases have been used to reduce the concentration of lipids contained in effluent, promoting hydrolysis of the oils and fats present. The aim of this work was to evaluate lipase production by fungi isolated from dairy effluent. We obtained 21 isolates of fungi, of the genus Penicillium, Aspergillus, Trichoderma and Fusarium. In the screening, nine isolates were selected on the basis of their capacity to grow in a medium containing olive oil as substrate. In submerged fermentation, the fungi E9 (Aspergillus), E21 (Aspergillus) and E20 (Penicillium) were the ones that presented the greatest enzymatic activity, from 1.250 to 2.250 U, using as cultivation medium the effluent collected from the treatment system equalizer.

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Aplicações sintéticas de lipases imobilizadas em polímeros/ Synthetic applications of immobilized lipases in polymers

Dalla-Vecchia, Roberto; Nascimento, Maria da Graça; Soldi, Valdir

Resumo em inglês The application of biocatalysis is a promising field related to new technologies for organic synthesis. The development of immobilization techniques is very important due to the multiple or repetitive use of a single batch of enzymes and the ability to stop the reaction rapidly, at any stage, by removing the enzymes. In most cases, after immobilization, enzymes and microorganisms maintain or even increase their activity and stability. This work presents an overview of the (mais) common methods for lipase immobilization in polymers and applications of these systems to obtain compounds of synthetic interest.

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Estudo da influência do solvente, carboidrato e ácido graxo na síntese enzimática de ésteres de açúcares/ Study of the influence of solvent, carbohydrate and fatty acid in the enzymatic synthesis of sugar esters by lipases

Paula, Ariela V. de; Barboza, Jayne C. de Souza; Castro, Heizir F. de

Resumo em inglês The aim of this work was to gain knowledge of enzymatic processes for the synthesis fatty acid esters of sugar, with the objective to develop an enzymatic process for the preparation of non-toxic biodegradable surface-active agents derived entirely from renewable resources. A wide range of data were collected for reaction conditions involving different sugars (glucose, fructose and sucrose), fatty acids (oleic, palmitic, lauric), solvents (hexane, heptane and t-butanol) a (mais) nd different sources of lipases in both free and immobilized forms. As a solvent t-butanol provided the best conditions to create a catalytic liquid phase in which the reaction occurs. Sugars were preferentially esterified in the following order: fructose > glucose > sucrose, depending on the enzyme preparation. For fructose no influence was found concerning de acyl donor and similar rates were achieved for all tested fatty acids. Ester synthesis was maximized for substrates containing fructose, lauric or oleic acids, t-butanol and lipase from porcine pancreas immobilized on polysiloxane-polyvinyl alcohol particles. Under such conditions molar conversions were higher than 50%.

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Organo-gel: um novo sistema para a imobilização de lipases e sua aplicação em síntese orgânica/ Organogels: a new system for lipases immobilization and its application in organic synthesis

Jesus, Paulo Cesar de; João, Jair Juarez; Silva, Pedro Luiz Ferreira da; Burlin, Giovani; Nascimento, Maria da Graça

Resumo em inglês Lipases have been immobilized in microemulsion-based organogels (MBG's) and successfully utilized for the enantioselective esterification, diesterification and transesterification reactions, in organic solvents at 25ºC. This methodology is described as a new alternative for the use of enzymes in organic solvents. High enzymic stability has been observed. We have also used this methodology for the successful resolution of chiral secondary alcohols. This is a convenient way of using this catalyst in organic solvents which employs small amounts of the enzyme (250mg/mL).

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Co-produção de lipase e biossurfactante em estado sólido para utilização em biorremediação de óleos vegetais e hidrocarbonetos/ Lipases and biosurfactant production by solid state fermentation for utilization in bioremediation of vegetable oils and hydrocarbons

Martins, Vilásia Guimarães; Kalil, Susana Juliano; Costa, Jorge Alberto Vieira

Resumo em inglês Recently lipases have been increasing in prominence due to its wide industrial application. The lipase production can be influenced by different variables such as the producing microorganism, carbon sources, aeration and agitation conditions, inductor type and the geometry of the reactor. Biosurfactants are composites of surface active produced by microbial cells which reduce superficial and interfacial tensions. The objective of this study was to verify the influence of (mais) different process variables in the lipase production during a fermentative process. The results showed that the concomitant production of lipases and biosurfactant was possible in different cultivation conditions.

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Purificação parcial e caracterização bioquímica de lipase extracelular produzida por nova linhagem de Rhizopus sp./ Production, partial purification and biochemical characterization of a novell Rhizopus sp. strain lipase

Pastore, Gláucia M.; Costa, Vinicius dos Santos R. da; Koblitz, Maria Gabriela B.

Resumo em português Lipases são enzimas capazes de catalizar uma grande gama de reações de interesse para as indústrias alimentícia, farmacêutica, química, entre outras. Esta versatilidade se deve também às diversas possibilidades de especificidade quanto ao substrato que lipases de diferentes fontes apresentam. Por este motivo, microrganismos produtores desta enzima vêm sendo procurados por grupos de pesquisa no mundo todo. Este trabalho apresenta as propriedades de uma lipase pro (mais) duzida por nova linhagem fúngica de Rhizopus sp. A enzima bruta apresentou condições ótimas de atividade a 40ºC em valores de pH entre 6,0 e 6,5. e manteve 50% ou mais de sua atividade quando aquecida por 60 minutos à temperaturas entre 40ºC e 55ºC. A atividade hidrolítica da lipase bruta foi maior quando o substrato testado foi a gordura de coco, demonstrando afinidade por ácidos graxos saturados de cadeia média. As frações I e II obtidas após purificação parcial da enzima apresentaram características bioquímicas semelhantes as do extrato bruto. Resumo em inglês Lipases are enzymes capable of catalyzing a great variety of reactions that are interesting to food, pharmaceutical, chemical, and other industries. This versatility is also due to the different substrate specificity possibilities that lipases from various sources. For this reason, lipase producing microorganisms are being searched by research groups around the world. This paper presents the properties of a extracellular lipase produced by a newly isolated strain of Rhizo (mais) pus sp. The crude enzyme showed optimal activity at 40ºC, between 6.0 and 6.5 pH values and kept 50% of it´s activity after treatment between 40ºC and 55ºC for 60 minutes. The hydrolytic activity of the crude extract was greater when coconut fat was used as substrate. This shows the affinity of the lipase to saturated medium chain fatty acids. The fractions I and II, that were obtained after the partial purification of the lipase, showed biochemical characteristics similar to the crude extract.

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Purificação parcial, por dois diferentes métodos cromatográficos, da lipase produzida por Rhizopus sp./ Partial purification of the lipase from Rhizopus sp by two different chromatographic methods

Koblitz, Maria Gabriela Bello; Pastore, Gláucia Maria

Resumo em português Lipases, especialmente as de origem microbiana, são largamente utilizadas em processos e na obtenção de produtos para as indústrias química, cosmética, farmacêutica e alimentícia. A produção de enzimas de elevada pureza é importante, principalmente, do ponto de vista do controle dos processos (ausência de interferentes), porém as etapas necessárias à purificação, em geral, provocam perdas na atividade das enzimas e aumentam seu custo final. O objetivo des (mais) te trabalho foi propor a melhor metodologia de purificação para a lipase de Rhizopus sp. através do teste de dois diferentes métodos cromatográficos (troca iônica e interação hidrofóbica) e, ainda verificar o melhor planejamento estatístico para caracterização bioquímica da mesma. Foi possível purificar parcialmente a lipase de Rhizopus sp. com o uso de coluna de DEAE Sepharose (troca aniônica) e de FENIL Sepharose (interação hidrofóbica). A primeira, embora mais seletiva para a enzima em questão, parece provocar redução de sua atividade. A presença de maiores concentrações de íons Na+1 na fração purificada por FENIL Sepharose parece contribuir para o aumento de atividade da lipase. Embora os resultados obtidos por análise multivariável para determinação das características bioquímicas da lipase sejam compatíveis com a análise univariável, aquele planejamento não foi considerado indicado no presente caso. Resumo em inglês Lipases, especially of microbial origin, are widely applied in processes and in the production of insumesfor the chemical, cosmetic, pharmaceutical and food industries. To produce highly pure enzyme is important to process control (absence of interferentes). However the necessary stages to the purification, in general, cause losses of activity and increases enzyme final cost. The aim of this work was to consider the best methodology of purification for the Rhizopus sp. li (mais) pase through the test of two different chromatographic methods (ion exchange and hydrophobic interaction) and also to verify the best statistical design for the biochemical characterization of the enzyme. It was possible to partially purify the Rhizopus sp lipase applying a DEAE Sepharose (anionic exchange) column and a PHENYL Sepharose (hydrophobic interaction) column. The first, although more selective for the enzyme in study, seems to cause reduction of its activity. The presence of higher concentrations of Sodium ions in the PHENYL Sepharose fraction seems to contribute for an increased activity of the lipase. Although the results obtained through the factorial design for the biochemical characteristics of the lipase were compatible with the single variable analysis, that statistical approach should not be indicated in the present case.

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Modificação bioquímica da gordura do leite/ Biochemical modification of milkfat

Nunes, Gisele Fátima Morais; Paula, Ariela Veloso de; Castro, Heizir Ferreira de; Santos, Júlio César dos

Resumo em inglês Recent advances for improving physicochemical and nutritional properties of lipids are reviewed, with emphasis on products attaining by biochemical processing of natural fats and oils. Enzymatic interesterification provides an important route to modify physical and nutritional properties of milkfat without generating trans isomers. This process makes use of lipases, a versatile class of enzyme that is able to perform efficiently the target modification in both solvent and (mais) solvent free systems. The present review covers important features of lipases, lipase-catalyzed interesterification reactions and their effects on the composition and texture of the resulting product.

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Influência das variáveis de processo na alcoólise enzimática de óleo de mamona/ Evaluation of the influence of process variables on enzimatic alcoholysis of castor oil

Oliveira, D.; Oliveira, J.V.; Faccio, C.; Menoncin, S.; Amroginski, C.

Resumo em português O potencial de aplicação de lipases em processos biotecnológicos para a modificação de óleos e gorduras tem sido objeto de grande interesse nos meios científico, econômico e industrial nos últimos anos. Além da atividade de hidrólise de ésteres, as lipases podem catalisar uma grande variedade de reações de esterificação, transesterificação e poliesterificação. A transesterificação inclui acidólise, interesterificação e alcoólise. Neste trabalho r (mais) eações de alcoólise de óleo de mamona para produção de ésteres de ácidos graxos foram estudadas devido a sua importância na obtenção de, por exemplo, agentes de antifricção, emulsificantes, intermediários para produzir uma numerosa quantidade de oleoquímicos e combustível alternativo ao diesel e/ou aditivo ao diesel de petróleo (biodiesel). Neste contexto, foi estudada a etanólise enzimática de óleo de mamona com lipase comercial (Lipozyme IM) usando n-hexano como solvente. Os experimentos foram realizados variando a temperatura, as concentrações de água e enzima no meio reacional e a razão molar óleo-etanol, de acordo com um planejamento de experimentos pré-estabelecidos. Um modelo empírico foi utilizado para avaliar a influência das variáveis de processo no rendimento e, desta forma, as condições de operação que maximizam a produção de ésteres foram estabelecidas para a enzima utilizada. Resumo em inglês The use of lipases as biocatalysts in ester synthesis has been the object of growing interest. In addition to glycerol ester hydrolysis, lipases can catalyze a wide variety of esterification, transesterification and polyesterification reactions. The transesterification includes acidolysis, interesterification and alcoholysis. We consider in this report the application of lipases in the alcoholysis of brazilian vegetable oil in the production of fatty acid esters due to it (mais) s importance as, for example, antifriction agents, food preservatives, emulsifiers and intermediates to produce a number of oleochemicals and fuel alternatives (biodiesel). In this work, enzymatic alcoholysis of castor bean oil with an immobilized lipase (Lipozyme IM) was accomplished using n-hexane as solvent. In order to maximize the esters production a Taguchi design was adopted varying temperature, water and enzyme concentrations in the reaction media and the oil:ethanol molar ratio. The reactions were monitorated by determining the glycerol production. An empirical model was built to evaluate the influence of the process variables on the conversion and afterwards the operating conditions that maximize esters production were established.

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Alternativa potencial para aproveitamento do glicerol gerado na produção de biodiesel: síntese enzimática de monolaurina por esterificação/ Potential alternative for using the glycerol generated in the biodiesel production: enzymatic synthesis of monolaurin by esterification

Freitas, Larissa; Santos, Julio C.; Barcza, Marcos V.; Castro, Heizir F. de

Resumo em inglês Esterification reactions of glycerol with lauric acid in solvent free system were carried out using lipases from several sources. All lipases were immobilized on polysiloxane-polyvinyl alcohol particles by covalent binding with high activity recovered. Among the tested enzymes, the Candida antarctica lipase allowed to attain the highest molar conversion (76%), giving similar proportions of monolaurin, dilaurin and low amount of trilaurin. To further improve the process, t (mais) he Response Surface Methodology (RSM) was used and optima temperature and molar ratio glycerol to lauric acid were found to be 45 ºC and 5:1, respectively. Under these conditions, 31.35% of monolaurin concentrations were attained and this result was in close agreement with the statistical model prediction.

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Comportamento de cristalização de lipídios estruturados obtidos a partir de gordura de palmiste e óleo de peixe/ Crystallization behavior of structured lipids produced from palm kernel fat and fish oil

Gamboa, Oscar Wilfredo Díaz; Gioielli, Luiz Antonio

Resumo em inglês The aim of this study is to evaluate the crystal structure of binary mixtures of palm kernel fat and fish oil, before and after chemical and enzymatic interesterification. The crystal structure was analyzed by polarized light microscopy. The addition of fish oil didn't change the palm kernel fat crystallization characteristics, spherullites of types A and B being observed. However, due to chemical and enzymatic interesterification, smaller crystals were obtained. There wa (mais) s no difference between chemical and enzymatic interesterification, probably as a function of acyl migration in discontinuous processes catalyzed by lipases.

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Cutinases fúngicas: propriedades e aplicações industriais/ Fungal cutinases: properties and industrial applications - review

Pio, Tatiana Fontes; Fraga, Laira Priscila; Macedo, Gabriela Alves; Kamimura, Eliana Setsuko

Resumo em inglês Cutinases (EC are also known as cutin hidrolases. These enzymes share catalytic properties of lipases and esterases, presenting a unique feature of being active regardless the presence of an oil-water interface, making them interesting as biocatalysts in several industrial processes involving hydrolysis, esterification and trans-esterification reactions. They are also active in different reaction media, allowing their applications in different areas such as food (mais) industry, cosmetics, fine chemicals, pesticide and insecticide degradation, treatment and laundry of fiber textiles and polymer chemistry. The present review describes the characteristics, potential applications and new perspectives for these enzymes.

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Hidrólise parcial enzimática da gordura de babaçu/ Partial enzymatic hydrolysis of babassu fat

OLIVEIRA, Andréa Lícia de Almeida; GIOIELLI, Luiz Antonio; OLIVEIRA, Maricê Nogueira

Resumo em português Lipases são enzimas de origem animal, vegetal ou microbiana que catalisam a hidrólise total ou parcial de óleos e gorduras, fornecendo ácidos graxos livres, acilgliceróis parciais e glicerol. O trabalho teve como objetivo verificar a ação da lipase comercial FAP (Amano Pharmaceutical Co.) no processo de hidrólise parcial da gordura de babaçu. Foi utilizada a Metodologia de Superfície de Resposta para representar o sistema na região estudada. O tratamento estat� (mais) �stico possibilitou analisar a influência das variáveis indepentes concentração de enzima (3 a 327U/mL) e tempo de reação (1 a 31h) na variável dependente: % de hidrólise. Os resultados experimentais observados nas reações, variaram de 6,52 a 41,44% de hidrólise da gordura de babaçu. Pela aplicação do modelo estatístico, os resultados estimados variaram de 13,57 a 43,80% de hidrólise. O nível de significância foi de 99% para o modelo % de hidrólise. Foi observado que 87,8% da variação da resposta pode ser explicada pela regressão múltipla, demostrando ser bom o ajustamento do modelo aos dados experimentais. Resumo em inglês Lipases are enzymes from animal, vegetal or microbial sources, that catalise the hydrolysis of oils and fats, in order to produce free fatty acids, acilglycerols partials and glycerol. The partial hydrolysis of babassu fat by microbial lipase FAP (Amano Pharmaceutical Co.) was studied. Response surface methodology was employed in order to develop mathematical models. Statistical treatment analysed the effects of independent variables: enzyme concentration (3 to 327U/mL) a (mais) nd reaction time (1 to 31 h), in dependent variable: % of hydrolysis. The experimental results observed in the reactions, ranged from 6.52 to 41.44% of hydrolysis of babassu fat. By applying the statistical model, the results ranged from 13.57 to 43.80% of hydrolysis.

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Isolamento de coliformes, estafilococos e enterococos de leite cru provenientes de tanques de refrigeração por expansão comunitários: identificação, ação lipolítica e proteolítica/ Isolation of coliforms, staphylococci, and enterococci in raw milk from communitarian expansion refrigeration tanks: identification, lipolytic and proteolytic action

Tebaldi, Victor Maximiliano Reis; Oliveira, Thales Leandro Coutinho de; Boari, Cleube Andrade; Piccoli, Roberta Hilsdorf

Resumo em português O isolamento e a identificação de microrganismos em leite cru se tornam interessantes do ponto de vista de saúde pública, pois dependendo das espécies isoladas, ações direcionadas podem ser tomadas visando a melhoria de sua qualidade. A deterioração do leite é conseqüência sobretudo do crescimento de microrganismos psicrotróficos, que produzem lipases e proteases termoestáveis que não são desnaturadas durante o processo de pasteurização, conferindo sabor (mais) es e odores rançoso e amargo, respectivamente. Assim, o objetivo deste trabalho foi isolar e identificar os principais gêneros de bactérias pertencentes à família Enterobacteriaceae, Gram-negativas oxidase positiva, gêneros Staphylococcus e Enterococcus, bem como atividade de lipases e proteases de 16 propriedades rurais do município de Boa Esperança-MG. As bactérias Gram-negativas foram isoladas em ágar eosina azul de metileno (EMB) e ágar Entérico Hektoen. Estafilococos foram isolados em ágar Baird-Parker e Enterococcus em ágar KF. Colônias de interesse foram coletadas e submetidas à coloração de Gram, e às provas de catalase e oxidase. Após esses procedimentos, os isolados selecionados foram identificados utilizando-se Bactray I, II e III; Api 20 Strep; e provas sugeridas pelo Bergey's Manual of Determinative Bacteriology. A identificação sorológica de Enterococcus foi realizada utilizando-se Prolex. O leite oriundo das 16 propriedades continha cepas de microrganismos fecais como Escherichia coli e Enterococcus do grupo D de Lancefield. Bactérias Gram-negativas oxidase positiva foram identificadas em cinco propriedades. Staphylococcus foram encontrados em 10 propriedades. O leite coletado nas fazendas investigadas possui microrganismos que comprometem sua qualidade. Todos os grupos de microrganismos testados revelaram atividades de lipase e protease. Resumo em inglês Isolation and identification of microorganisms in raw milk is interesting from the viewpoint of public health, since, depending on the species isolated, directed actions may be taken to improve milk quality. Milk deterioration is mainly the result of the growth of psychrotrophic microorganisms that produce heat-resistant lipases and proteases which are not denatured during pasteurization, conferring rancid and sour flavors, respectively. Thus, this work aimed at isolating (mais) and identifying the main genera of bacteria belonging to the Enterobacteriaceae family, oxidase-positive Gram-negative, Staphylococcus and Enterococcus genera, as well as determining lipase and protease activity in 16 rural farms in Boa Esperança-MG, Brazil. The Gram-negative bacteria were isolated in Eosin Methylene Blue (EMB) and Hektoen Enteric agar media. Staphylococci were isolated in Baird-Parker agar and Enterococcus in KF agar. Colonies of interest were collected and submitted to Gram stain and to catalase and oxidase tests. Following these procedures, the isolates selected were identified using Bactray I, II and III; Api 20 Strep and tests suggested by Bergey's Manual of Determinative Bacteriology. Sorological identification of Enterococcus was carried out using Prolex. Milk from the 16 rural properties contained strains of fecal microorganisms, such as Escherichia coli and Enterococcus from the Lancefield D group. Oxidase-positive Gram-negative bacteria were identified in five farms. Staphylococcus was found in 10 farms. Milk collected from the farms investigated contained microorganisms that compromise its quality. All the microorganism groups tested showed lipase and protease activities.

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Produção de enzimas extracelulares por Crinipellis perniciosa/ Production of extracellular enzymes by Crinipellis perniciosa

Bastos, Cleber N.

Resumo em português Isolados de Crinipellis perniciosa, obtidos a partir de cacaueiro (Theobromae cacao), cupuaçuzeiro (T. grandiflorum) e solanáceas silvestres foram testados quanto à capacidade de produzirem enzimas extracelulares que degradam celulose, amido, lipídios e lignina. A produção de todas as enzimas foi determinada em meios sólidos e representada por uma estimativa, baseada na intensidade de cor, ou pela avaliação do diâmetro dos halos formado nos meios. Foi detectada (mais) variabilidade entre os isolados na capacidade de produzir enzimas celulolíticas, amilases, lipases, polifenol-oxidases, peroxidases e esterases. Quanto às enzimas proteolíticas, todos os isolados apresentaram alto nível de atividade, não sendo observada diferença no comportamento entre eles. Por outro lado, nenhum dos isolados produziu pectinase, urease e fosfatase-ácida. Os papéis das enzimas líticas produzidas pelos isolados de C. perniciosa na patogênese e na produção de basidiomas são discutidos Resumo em inglês Strains of Crinipellis perniciosa isolated from cocoa (Theobromae cacao), cupuassu (T. grandiflorum) and wild solanaceous were tested for their ability to produce extracellular enzymes which degrade cellulose, starch, lipids and lignin. The production of all enzymes was examined in solid media and was estimated based on the intensity of color or on the diameter of halos formed on the media. Variability was detected among the isolates in their capacity to produce celluloly (mais) tic enzymes, amylase, lypase, phenol-oxidase, peroxidase and esterase. All isolates presented high level of activity, regarding proteolytic enzymes. On the other hand, none of the isolates produced pectinase, urease and acid phosphatase. The roles of lytic enzymes of C. perniciosa on pathogenesis and on basidiome production are discussed.

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Progressos recentes e novas perspectivas em farmacoterapia da obesidade/ Recent progress and novel perspectives on obesity pharmacotherapy

Faria, André M.; Mancini, Marcio C.; Melo, Maria Edna de; Cercato, Cintia; Halpern, Alfredo

Resumo em português O aumento da prevalência da obesidade, nas últimas décadas, é alarmante, o que implica um grande número de pacientes sob risco de complicações metabólicas e cardiovasculares associadas. A eficácia modesta a longo prazo das modificações de estilo de vida isoladamente exige a necessidade de intervenções mais agressivas, seja por meio do uso adjuvante de medicamentos ou da abordagem mais radical cirúrgica. A cirurgia bariátrica, embora até hoje tenha se mostr (mais) ado o método mais efetivo de tratamento dessa enfermidade, pode estar associada a complicações nutricionais e metabólicas ainda não totalmente esclarecidas. Contrasta com esse fato a disponibilidade limitada de agentes antiobesidade atualmente no mercado, além de fatos históricos que envolveram a suspensão de alguns fármacos previamente existentes, por questões de segurança. Este artigo tem como objetivo apresentar dados recentes de estudos clínicos de novas drogas propostas para o tratamento da obesidade com perspectivas breves de serem lançadas no mercado, caso passem pela aprovação das agências regulatórias. Nesta revisão serão discutidas a eficácia e a segurança desses fármacos, que incluem a lorcaserina (agonista serotoninérgico seletivo 5-HT2c), tesofensina (inibidor triplo de recaptação de monoaminas), liraglutide (análogo do GLP-1) e cetilistate (inibidor de lipases gastrointestinais), além das combinações de bupropiona/naltrexona, bupropiona/zonisamida, fentermina/topiramato e pramlintide/metreleptina. Resumo em inglês Obesity prevalence has risen dramatically over the past decades, which poses a great number of patients at risk of metabolic and cardiovascular complications. Long-term efficacy of lifestyle modification isolated has shown to be modest which, therefore, urges the need of more aggressive interventions such as adjuvant pharmacotherapy or the more radical surgical approach. Bariatric surgery has proven to date to be the most effective treatment, although it may be associated (mais) with nutritional and metabolic complications not yet completely recognized. By contrast, there is limited availability of antiobesity agents currently in the market, as well as historical facts involving the suspension of previously existing medications due to safety concerns. This article aims to present recent data on clinical trials of novel weight-loss drugs with short perspective to enter the market, if approved by the regulatory agencies. This review will discuss the efficacy and safety of these compounds, which include lorcaserin (selective serotonin 5-HT2c agonist), tesofensine (triple monoamine reuptake inhibitor), liraglutide (GLP-1 analogue) and cetilistat (gastrointestinal lipase inhibitor), as well as the combination therapies of bupropion/naltrexone, bupropion/zonisamide, phentermine/topiramate and pramlintide/metreleptin.

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Pré-hidrólise enzimática da gordura de efluente da indústria de pescado objetivando o aumento da produção de metano/ Enzymatic hydrolysis of fat from fish industry effluents aimed at increasing methane production

Valente, Angélica Moreira; Alexandre, Verônica Marinho; Cammarota, Magali Christe; Freire, Denise Maria Guimarães

Resumo em português A aplicação de preparados enzimáticos sólidos (PES) ricos em lipases foi avaliada no tratamento anaeróbio de efluente de indústria de conservas de pescado. O PES foi produzido pelo fungo Penicillium simplicissimum por fermentação em meio sólido (FMS) de resíduo industrial, sendo empregado na hidrólise de gorduras presentes no efluente a fim de viabilizar a utilização de metano como fonte de energia. O efluente contendo 1500 mg O&G.L-1 foi hidrolisado com 0,2, (mais) 0,5 e 1,0% (m/v) de PES a 30 °C por até 18 horas. O efeito do pré-tratamento enzimático dos O&G não foi significativo com relação à remoção de DQO, pois, independente das condições adotadas, obtiveram-se valores de 91 a 95%. Por outro lado, a produção específica de metano apresentou valores que variaram com a adição do PES e o tempo de hidrólise. Em experimentos controle (sem adição de PES), a produção específica de metano aumentou com o tempo de incubação, atingindo um máximo com 18 horas (138 mL CH4.g-1 DQOinicial). No entanto, valores mais elevados de produção específica de metano foram obtidos com 0,5 e 1,0% de PES, destacando-se a hidrólise com 0,5% de PES e 8 horas de hidrólise, com 216 mL CH4.g-1 DQOinicial. Quando se compara o experimento controle 0 horas (efluente bruto) com o efluente hidrolisado com 0,5% de PES durante 8 horas, um aumento de 2,7 vezes na produção específica de metano foi observado, indicando que a matéria orgânica foi mais facilmente assimilada pelos microrganismos anaeróbios nesta última condição. Resumo em inglês The application of solid lipase-rich enzymatic preparations (SEP) in the anaerobic treatment of industrial effluents from canned fish processing was investigated. SEP was produced by the fungus Penicillium simplicissimum through solid-state fermentation (SSF) of industrial wastes, and it was used in the hydrolysis of fats present in the effluents in order to facilitate the use of methane as a source of energy. The effluent (1500 mg O&G.L-1) was hydrolyzed with 0.2, 0.5 an (mais) d 1.0% (w/v) of SEP at 30 °C for up to 18 hours. The effect of the enzymatic pre-treatment of O&G on the COD removal was not observed because regardless of the conditions adopted, values from 91 to 95% were obtained. The specific production of methane presented values that varied with the addition of SEP and time of hydrolysis. In the control experiments, in which the flasks were incubated at 30 ºC without the addition of SEP, the specific methane production increased with the time of incubation reaching the maximum peak at 18h (138 mL CH4.g-1 CODconsumed). However, higher values of specific methane production were obtained with 0.5 and 1.0% of SEP highlighting the hydrolysis with 0.5% of SEP and 8 hours of hydrolysis with 216 mL CH4.g-1 CODcomsumed. When comparing the control 0 hour (raw effluent) with the effluent hydrolyzed with 0.5% of SEP for 8 hours, it could be observed that the specific methane production increased by 2.7 times indicating that the substrate available for the action of anaerobic microorganisms were more easily assimilated.

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