Biodegradation of lignin of Bambusa nutans by the isolate Inonotus pachyphloeus JP-1

Abstract

A delignification pretreatment of raw materials for paper and pulp industry is important as traditional chemical degradation is hazardous to health and the environment. The aim of the present study was to identify potential laccase producing fungi with special attention on their feasibility for the degradation of lignin of Bambusa nutans. Among 155 fungal isolates from bamboo stacking area of a paper mill, Inonotus pachyphloeus JP-1, characterized by morphological and internal transcribed spacer sequence analysis was found to have best potential for it. Laccase enzyme activity of the isolate JP-1 was studied for 72–288 h, and the highest activity of 666.8 nkat/ml was recorded at 144 h using 1 mM of CuSO4 as an inducer. B. nutans samples pretreated with the isolate recorded higher lignin degradation (45.80%) with minimum loss of cellulose content (2.24%) after 30 days of treatment. Furthermore, scanning electron microscopy, X-ray diffractometery and fourier transform infrared spectra of untreated and treated samples confirmed the effect of pretreatment on the cellular structure of B. nutans. This is the first report on I. pachyphloeus as a potent lignin degrader which can be further exploited for the development of clean technologies for paper and pulp industries.