Biopulping studies using an effluent isolate Curvularia lunata LW6

The lignin is unwanted constituent for a pulp and paper manufacturer, which must be removed for getting good quality paper. The aim of bio-delignification of raw material is to make pulping process easier, to save energy requirements, to improve pulp properties and to minimize pollution. The present study aims to find suitability of isolate Curvularia lunata LW6 for biopulping of sugarcane bagasse. The organism was screened from effluent of pulp and paper mill and tested for lignolytic ability. The isolate produced the enzyme lignin peroxidase (3.31 U/mg of protein) and laccase (6.12 U/mL). It showed good saprophytic ability (38.14 cm super(2)) on sterile bagasse when supplemented with glucose and yeast extract as co-substrate. The solid-state fermentation of bagasse for biopulping resulted in loss of weight by 21.66%, while lignin content and kappa number decreased by 44.05% and 40.78%, respectively. The chemical pulping showed 55.25% reduction in kappa number; however, it required high temperature, pressure and alkaline medium. The mutagenesis studies showed slight decrease in cellulase activity of the isolate.