Lignolytic enzyme production by Pleurotus pulmonarius in different agro wastes under solid state fermentation

Abstract

Lignin modifying enzymes produced by white rot basidiomycetes fungi during their secondary metabolism are non specific with high oxidative capacity that is capable of mineralizing lignin. Among the white rot basidiomycetes fungi tested under solid and liquid screening, Pleurotus pulmonarius, P. sajor-caju and Schizophyllum commune produced all the three types of lignolytic enzymes viz., laccase, Lignin peroxidase (LiP) and Manganese peroxidase (MnP). Among them, P. pulmonarius was tested for the lignolytic enzyme production in different farm agro wastes viz., sugarcane, banana, millets, pulses, cocopeat, cocoa wastes, coir pith and oil palm under solid state fermentation (SSF). Among the enzymes, laccase and LiP was produced in significant levels by P. pulmonarius from 21^st   to 28^th day under SSF compared to MnP. Among the substrates tested, P. pulmonarius produced significant levels of laccase in banana, oil palm, coir pith and millets, where as LiP showed preference for substrates like sugarcane, banana, pulses and cotton and highest MnP was produced in sugarcane, pulses, cotton and millets. The organic substrates viz., wheat bran and ground nut cake each@ 5 per cent and inorganic substrates viz., copper sulphate and manganese sulphate each at 150 µM enhanced the lignolytic enzymes production of P. pulmonarius in liquid medium. The results from this study offers scope for application of white rot fungi P. pulmonarius for biodegradation of agrowastes as well for recycling of the agro wastes for the commercial production of edible mushrooms under integrated farming system to benefit the farming community.