Isolation of lignocelluloses degrading microbes from soil and their screening based on qualitative analysis and enzymatic assays

Abstract

Crop residues (CRs) composed of structurally complex lignocellulosic material which is resistant to degradation due to various biologically stable linkages present in it. Enhancing the process of its biological degradation using microbial strains capable of decomposing lignocellulose would not only solve the problem of CR disposal but also recycle the organic carbon, NPK and other plant nutrients back into the soil. This study was aimed at isolating and screening of the lignocellulose decomposing microbes from various sources such as crop residue incorporated soil, forest soil, soil near decaying wood, compost pit and dump yard. Total of 15 fungi and 6 bacteria were isolated in the form of pure colonies and screened for cellulose and lignin decomposing ability using carboxymethylcellulose (CMC) and tannic acid (TA) agar media on the basis of appearance of clear zone. Five fungal and two bacterial cultures identified as lignocellulose decomposers were further screened quantitatively for CMCase and filter paperase enzyme assay by standard protocols. Two fungal strains, identified as Trichoderma species and Aspergillus species showed significant enzymatic activity and can be utilized as a potential lignocellulose decomposer.