L-glutaminase production by Trichoderma koningii under solid-state fermentation

Abstract

Solid state fermentation was conducted for the production of L-glutaminase by Trichoderma koningii Oud.aggr. using different agro-industrial byproducts inlcuding wheat bran, groundnut residues, rice hulls, soya bean meal, corn steep, sesamum oil cake, cotton seed residues and lentil industrial residues as solid substrates. Wheat bran was the best substrate for induction of L-glutaminase (12.1 U/mg protein) by T. koningii. The maximum productivity (23.2 U/mg protein) and yield (45.0 U/gds) of L-glutaminase by T. koningii occurred using wheat bran of 70% initial moisture content, initial pH 7.0, supplemented with D-glucose (1.0%) and L-glutamine (2.0% w/v), inoculated with 3 ml of 6 day old fungal culture and incubated at 30°C for 7 days. After optimization, the productivity of L-glutaminase by the solid cultures of T. koningii was increased by 2.2 fold regarding to the submerged culture.