Desenvolvimento de bioprocessos para produção e aplicação de enzimas, extração de amido e produção de leveduras fibrolíticas a partir de resíduos agroindustriais
Carregando...
Arquivos
Data
2020-02-19
Autores
Souza, Joyce Faria de
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O estudo da utilização de resíduos agroindustriais para desenvolvimento e otimização de bioprocessos econômicos tem sido intensificado nos últimos anos. Neste trabalho foi realizada uma revisão que buscou sintetizar informações atuais sobre as condições nutricionais de cultivo que influenciam na síntese de enzimas celulolíticas e xilanolíticas produzidas por microrganismos, com destaque para os resíduos agroindustriais e alguns exemplos de linhagens probióticas e seu potencial na nutrição e saúde animal. Estudou- se também o desenvolvimento de um processo integrado de técnicas que envolveram desde a biossíntese de enzimas fíbrolíticas (celulases e xilanases), a partir de cultivo fúngicos em meios formulados com resíduos, até a aplicação de métodos físicos, bioquímicos e microbiológicos no bagaço de mandioca, a fim de se obter maior rendimento de amido na fecularias e novos co-produtos para uso como aditivos na formulação de ração animal. Os cultivos para produção enzimática foram realizados com Trichoderma reesei QM9414 em cultivo submerso a 28°C, 150 rpm por 15 dias utilizando-se farelo de trigo (FT), polpa cítrica (PC) e dreche cervejeiro (DC) suplementado com um conjunto de sais. O estudo da formulação do meio com a combinação destes substratos foi realizado por meio do delineamento experimental de misturas, e as melhores combinações foram com a utilização de 100% (m/v) de dreche cervejeiro (celulase total e xilanase), além das combinações de 16,67% de farelo de trigo, 16,67% de polpa cítrica e 66,7% de dreche cervejeiro (endoglucanase, exoglucanase e β- glicosidase). Foi realizado também um estudo quanto à demanda de minerais, sacarose e extrato de levedura na produção de celulases e xilanases, e selecionados os quatro melhores nutrientes para avaliar a produção enzimática. Os estudos demonstraram um aumento 2,38 vezes (1 FPU/g) para celulase total comparado a produção obtida com o delineamento experimental utilizando-se a melhor combinação dos nutrientes extrato de levedura, sacarose, zinco, fosfato de potássio e dreche cervejeiro. Por meio da utilização de diferentes concentrações de tween 80 para a produção enzimática observou-se uma redução substancial do tempo de cultivo para a biossíntese de celulases. Técnicas de gelatinização do amido e aplicação de enzimas fibrolíticas foram estudadas no bagaço de mandioca a fim de aumentar a extração de amido reduzindo-se assim as perdas nas fecularias. A cinética de gelatinização (80°C) seguida de filtração do bagaço de mandioca resultou em duas frações: líquida (Fração Amilácea) e fibrosa (Fração Fibrosa 1), a fração líquida apresentou grande extração de amido (eficiência de 72,4%) com pureza de 77%.As hidrólises do bagaço de mandioca para extração amido com o extrato BIOENJ19 (obtido do cultivo de T. reesei), celulase comercial (Cellic CTec2) e xilanase comercial (Celluclast) não foram muito eficientes se comparadas à técnica da gelatinização. A Fração Fibrosa 1 obtida por meio da gelatinização foi submetida a uma hidrólise enzimática obtendo-se além de amido, açúcares redutores (1,27% para Celic CTec2 e 0,51% para o extrato BIOEJ19) e uma nova fração fibrosa (Fração Fibrosa 1-1). Os produtos desta hidrólise foram usados para formulação de um meio de cultivo visando a propagação das leveduras fibrolíticas Rhodotorula mucilaginosa e Wickerhamomyces onychis, realizada em batelada alimentada a 28°C, 180 rpm por 5 dias. Após o cultivo foram obtidas conversões do substrato em biomassa de 0,14 g/g (R. mucilaginosa) e 0,12 g/g (W. onychis), indicando o potencial de produção destas leveduras especiais com estes resíduos e um potencial aumento do valor agregado destes resíduos com uso destas tecnologias.
The study of the use of agro-industrial waste for the development and optimization of economic bioprocesses has been intensified in recent years. In this work, a review was carried out that sought to synthesize current information on the nutritional conditions of cultivation that influence the synthesis of cellulolytic and xylanolic enzymes produced by microorganisms, with emphasis on agro-industrial residues and some examples of probiotic strains and their potential in animal nutrition and health. We also studied the development of an integrated process of techniques that involved since the biosynthesis of fibrolytic enzymes (cellulases and xylanases), from fungal cultures in media formulated with residues, to the application of physical, biochemical and microbiological methods in the bagasse was studied, in order to obtain higher starch yield in starchy mills and new co-products for use as additives in the formulation of animal feed. Cultivations for enzymatic production were carried out with Trichoderma reesei QM9414 in submerged fermentation at 28 ° C, 150 rpm for 15 days using wheat bran (FT), citrus pulp (PC) and brewery spent malt (BSM) supplemented with a set of salts. The study of the formulation of the medium with the combination of these substrates was carried out through the experimental design of mixtures, and the best combinations were with the use of 100% (w / v) of brewery spent malt (total cellulase and xylanase), beside to the combinations 16.67% wheat bran, 16.67% citrus pulp and 66.7% brewery spent malt (endoglucanase, exoglucanase and β-glucosidase). A study was also carried out regarding the demand for minerals, sucrose and yeast extract in the production of cellulases and xylanases, and the four best salts were selected to evaluate enzyme production. The studies showed a 2.38 fold increase (1 FPU / g) with the best combination of nutrients yeast extract, sucrose, zinc and potassium phosphate and brewery spent malt. The use of different concentrations of tween 80 was evaluated, substantially reducing the culture time for cellulases biosynthesis. Techniques of starch gelatinization and application of fibrolytic enzymes were studied in the cassava bagasse in order to increase the extraction of starch thus reducing losses in the starch mills. The gelatinization kinetics (80 ° C) followed by filtration of the cassava bagasse resulted in two fractions: liquid (starchy) and fibrous (fibrous fraction 1), resulting in a large extraction of starch (72.4% efficiency) with purity of 77%. The hydrolysis of cassava bagasse for starch extraction with the BIOENJ19 extract (obtained from the cultivation of T. reesei) or commercial enzyme (Cellic CTec2) was not very efficient compared to the gelatinization technique. However, after enzymatic hydrolysis of fibrous fraction 1, in addition to starch, reducing sugars (1.27% for Celic CTec2 and 0.51% for BIOEJ19 extract) were obtained, in addition to a new fibrous fraction (fibrous fraction 1- 1). The products of this hydrolysis were used to formulate a culture medium, aiming the propagation of fibrolytic yeasts Rhodotorula mucilaginosa and Wickerhamomyces onychis, carried out in batches fed at 28 ° C, 180 rpm for 5 days. After cultivation, substrate conversions were obtained in biomass of 0.14 g / g (R. mucilaginosa) and 0.12 g / g (W. onychis), indicating the potential of production of these special yeasts with these residues and potential increase of added value of these residues with the use of these technologies.
The study of the use of agro-industrial waste for the development and optimization of economic bioprocesses has been intensified in recent years. In this work, a review was carried out that sought to synthesize current information on the nutritional conditions of cultivation that influence the synthesis of cellulolytic and xylanolic enzymes produced by microorganisms, with emphasis on agro-industrial residues and some examples of probiotic strains and their potential in animal nutrition and health. We also studied the development of an integrated process of techniques that involved since the biosynthesis of fibrolytic enzymes (cellulases and xylanases), from fungal cultures in media formulated with residues, to the application of physical, biochemical and microbiological methods in the bagasse was studied, in order to obtain higher starch yield in starchy mills and new co-products for use as additives in the formulation of animal feed. Cultivations for enzymatic production were carried out with Trichoderma reesei QM9414 in submerged fermentation at 28 ° C, 150 rpm for 15 days using wheat bran (FT), citrus pulp (PC) and brewery spent malt (BSM) supplemented with a set of salts. The study of the formulation of the medium with the combination of these substrates was carried out through the experimental design of mixtures, and the best combinations were with the use of 100% (w / v) of brewery spent malt (total cellulase and xylanase), beside to the combinations 16.67% wheat bran, 16.67% citrus pulp and 66.7% brewery spent malt (endoglucanase, exoglucanase and β-glucosidase). A study was also carried out regarding the demand for minerals, sucrose and yeast extract in the production of cellulases and xylanases, and the four best salts were selected to evaluate enzyme production. The studies showed a 2.38 fold increase (1 FPU / g) with the best combination of nutrients yeast extract, sucrose, zinc and potassium phosphate and brewery spent malt. The use of different concentrations of tween 80 was evaluated, substantially reducing the culture time for cellulases biosynthesis. Techniques of starch gelatinization and application of fibrolytic enzymes were studied in the cassava bagasse in order to increase the extraction of starch thus reducing losses in the starch mills. The gelatinization kinetics (80 ° C) followed by filtration of the cassava bagasse resulted in two fractions: liquid (starchy) and fibrous (fibrous fraction 1), resulting in a large extraction of starch (72.4% efficiency) with purity of 77%. The hydrolysis of cassava bagasse for starch extraction with the BIOENJ19 extract (obtained from the cultivation of T. reesei) or commercial enzyme (Cellic CTec2) was not very efficient compared to the gelatinization technique. However, after enzymatic hydrolysis of fibrous fraction 1, in addition to starch, reducing sugars (1.27% for Celic CTec2 and 0.51% for BIOEJ19 extract) were obtained, in addition to a new fibrous fraction (fibrous fraction 1- 1). The products of this hydrolysis were used to formulate a culture medium, aiming the propagation of fibrolytic yeasts Rhodotorula mucilaginosa and Wickerhamomyces onychis, carried out in batches fed at 28 ° C, 180 rpm for 5 days. After cultivation, substrate conversions were obtained in biomass of 0.14 g / g (R. mucilaginosa) and 0.12 g / g (W. onychis), indicating the potential of production of these special yeasts with these residues and potential increase of added value of these residues with the use of these technologies.
Descrição
Palavras-chave
Resíduos agroindustriais, Enzimas fibrolíticas, Leveduras probióticas, Trichoderma reesei QM 9114, Fibrolytic enzymes, Probiotic yeasts, Agro-industrial residues