Lentinus citrinus (Walleyn e Rameloo) DPUA 1535: Crescimento, produção e extração de proteases por fermentação submersa

Abstract

Lentinus citrinus (Walleyn e Rammeloo) DPUA 1535 from Culture Collections DPUA 1535/UFAM was analyzed as the production of proteases by submerged culture. A full factorial design 25 with three central points was established to evaluate the influence of nutrient sources, pH of the culture medium, temperature and incubation time, in the production of biomass and proteases. The extraction of proteases from culture broth with higher activity was prepared by aqueous two-phase systems, PEG/phosphate by using a full factorial design 23 with three central points. The results showed that the best condition for growth and proteases production was determinated in medium formulated with soluble starch, gelatin, pH 7,0, 25 oC in 5 days. It was found, in culture conditions, that only nitrogen source and temperature were significant in growth of L. citrinus, while for proteases production all variables were statistically significant. In PEG-phosphate systems, in all runs, the proteases moved to top phase, as well as the best conditions for extraction of enzymes were with obtained with PEG 6000, 17,5% (w/w) and phosphate 25% (w/w).