Surfactant, Nitrogen and Carbon Media Optimization for Trichoderma Asperellum LBKURCC1 Laccase Production by Flask Solid State Fermentation of Rice Straw

Abstract

Laccase is an important industrial enzyme used in the paper, food and textile industry. It is produced by many different organisms, including filamentous fungi. Trichoderma asperellum LBKURCC1 is a strain isolated from Riau soil, which can produce laccase by solid state fermentation (SSF) of rice husk and rice straw. The aim of this work was to optimize SSF production of laccase from rice straw, through optimizing Nitrogen, Carbon and surfactant supplements to the fermentation media. Effect of surfactant, nitrogen supplement, and carbon supplement were evaluated by using a Central Composite Design (CCD) and surface response analysis. The concentration of the surfactant, Tween-20, at all concentration levels tested had no significant effect to the model. In contrast, the nitrogen and carbon supplement concentrations were significant factors (P-Value<0.05) enhancing laccase production. Optimum conditions for laccase production were 23 g/L nitrogen and 1% carbon supplement, giving a maximum laccase activity of 56.8 U/L enzyme extracted, equivalent to 0.7 U per g rice straw fermented. Optimizing the nitrogen and carbon supplement increased yields up to 3 times the level obtained in a non-optimized media.