Production of Enzymatic Extract with High Cellulolytic and Oxidative Activities by Co-Culture of Trichoderma reesei and Panus lecomtei

This work aimed to produce enzymatic fungi extracts with hydrolytic and oxidative activities to hydrolyze lignocellulosic biomasses efficiently. For this, the fungi Trichoderma reesei and Panus lecomtei were co-cultured using the vegetable biomasses oil palm decanter cake, wheat bran, and cottonseed cake as substrates in submerged fermentation. T. reesei and P. lecomtei showed partially compatible positive interaction on plates. The co-cultures respond positively to variations of temperature and inoculum interval, generating extracts responsible for higher hydrolysis yield when grown at 25 degrees C, and P. lecomtei is inoculated 24 h after T. reesei. The enzymatic extract production of co-cultures was also improved by modifying the components of the initial media and evaluating enzymatic activities, hydrolysis of sugarcane bagasse pretreated by autohydrolysis and ethanol production as a response. Five culture media were evaluated with variations in the composition of nutritional elements, minerals and substrates. The best extract showed a maximum cellulose hydrolysis efficiency of 68.7% compared with 44.8% of the initial medium. The ethanolic fermentation of hydrolysates obtained by co-culture extracts showed higher ethanol yields than monocultures. This work demonstrates the use of fungi co-cultures to produce enzymatic extracts composed of cellulolytic, hemicellulolytic, and ligninolytic enzymes complexes, which allow hydrolyzing pretreated lignocellulosic biomass with high efficiency, generating hydrolysates that are easier fermented by yeast.

Automated summary

This study aimed to produce enzymatic extracts from co-cultured fungi with hydrolytic and oxidative activities for efficient hydrolysis of lignocellulosic biomasses. The co-cultures of Trichoderma reesei and Panus lecomtei showed positive interaction and responded positively to variations in temperature and inoculum interval. The enzymatic extract production of co-cultures was improved by modifying the media composition, resulting in higher hydrolysis yields and ethanol production. This work demonstrates the use of fungi co-cultures to produce enzymatic extracts for efficient hydrolysis and fermentation of pretreated lignocellulosic biomass.