Enzyme complexes production by A. niger from soybean under solid state fermentation/Producao de complexos enzimaticos por A. niger a partir de soja por fermentacao em estado solido

Soybean has a wide availability of biochemical compounds as proteins, polysaccharides, lipids, carbohydrates, minerals, vitamins, fibers, lecithin, among others, making interesting its employment as substrate for solid state fermentation. Although the process of SSF is not extensively used industrially like the submerged fermentation (SmF), it can be a viable alternative, since presents higher results of productivity, especially at the cultivation of filamentous fungi and enzymes production. In this way, this study compared the production of different types of enzymes through solid-state fermentation, using different types of soybean cultures (organic, transgenic and conventional) with the fungus A. niger. We accomplished the characterization of the substrates for the production of amylase, protease and lipase, evaluation of the growth curves of the microorganism and the optimal conditions of enzymes production using experimental design. The highest enzyme activities in the study of fermentation parameters were observed for the protease, using conventional soybeans with initial moisture of 50%, 144h of fermentation, initial inoculum concentration of 4.106 spores [g.sup.-1] and particle size of 0.6 mm. The study of process optimization indicated that the best results of enzyme activity for the protease were obtained at pH 3.0 and particle size of soybean fragmentation of 0.6 mm. Keywords: solid fermentation, experimental design, enzymes. A soja possui ampla disponibilidade de componentes bioquimicos como proteinas, polissacarideos, lipidios, carboidratos, minerais, vitaminas, fibras, lecitina, dentre outros, tornando interessante sua utilizacao como substrato para a fermentacao em estado solido (FES). Este processo, apesar de nao ser tao utilizado industrialmente quanto a fermentacao submersa (Fsm), apresenta-se viavel, pois tem apresentado resultados superiores de produtividade, principalmente no cultivo de fungos filamentosos e na producao de enzimas. Assim, o objetivo deste trabalho foi o de comparar a producao de diferentes tipos de complexos enzimaticos por FES utilizando diferentes tipos de sojas (organica, transgenica e convencional) com o fungo Aspergillus niger. Realizou-se a caracterizacao dos substratos para a producao de amilase, protease e lipase, avaliacao das curvas de crescimento do microrganismo e das condicoes otimas de producao da protease utilizando planejamento de experimentos. As maiores atividades enzimaticas no estudo dos parametros