Use of agroindustrial wastes for the production of cellulases by Penicillium sp. FSDE15

Abstract

Cellulase refers to a group of enzymes like endoglucanases (CMCase), exoglucanases and β-glucosidase that have great industrial importance for the production of second-generation ethanol, e.g. The present study aimed to evaluate the CMCase and β-glucosidase activities of the fungal strain Penicillium sp. FSDE15 using different agroindustrial wastes (wheat bran, sugarcane bagasse and sugarcane straw) as carbon sources to the basal medium during Submerged Fermentation (SFm). When the medium presented wheat bran, highest CMCase and β-glucosidase yields were 1.03 U/mL (96 h) and 1.68 U/mL (168 h), respectively. For sugarcane bagasse medium, maximum enzymatic activity values were observed in 120 h culture (1.38 U/mL for CMCase and 0.55 U/mL for β-glucosidase). Sugarcane straw medium presented highest enzymatic yields after 120 h culture (1.02 U/mL of CMCase and 0.39 U/mL of β-glucosidase). The response surface methodology showed highest CMCase (1.3 U/mL) and β-glucosidase (6.5 U/mL) activities in the presence of lower levels of wheat bran (1%) (w/w), inoculum concentration of 105 spores/mL, temperatures of 41 °C and 33 °C, respectively. Penicillium sp. FSDE15 presented two isoforms of CMCase (150 kDa and around 30 kDa) and one isoform of β-glucosidase (70 kDa). Our study demonstrated that the production of cellulases with high activity by Penicillium sp. FSE15 in a culture medium with agroindustrial wastes, such as wheat bran, might be a promising alternative to reduce the cost of these molecules and facilitate their use in various industrial processes.