Lignocellulose degradation and production of lignin modifying enzymes by Schizophyllum commune IBL 06 in solid state fermentation
Abstract The modification of lignin is recognized as an important aspect of the successful refining of lignocellulosic biomass. Schizophyllum commune a white rot basidiomycete was studied for ligninolytic enzymes (manganese peroxidase, lignin peroxidase and laccase) production in solid state fermentation (SSF) of rice straw. Various physiological factors such as incubation time, culture pH, incubation temperature, C:N ratio and addition of mediators were optimized to enhance enzymes productivity. Maximum enzyme recoveries were obtained at pH, 5.0; temperature, 35 degC; C:N ratio, 20:1; mediator, MnSO 4 inoculum size, 4 mL after incubation time of 144 h. The crude ligninolytic extract thus produced was used for delignification of various agro industrial residues. The enzyme extract caused 61.7% 47.5% 72.3% and 67.2% lignin removal from banana stalk, corn cobs, sugarcane bagasse, and wheat straw, respectively. The optimally delignified substrate was enzymatically digested by crude cellulase extract from Trichoderma harzaianum that resulted 47.3% and 69.4% cellulose hydrolysis from the native and pre treated bagasse, respectively. The results suggested that lignocellulosic waste could be utilized as low cost substrate for the production of enzymes which play significant role in many industrial and biotechnological sectors.