Mutation breeding of Trichoderma koningii and optimization of solid-state fermentation conditions

Trichoderma koningii 3.4261 was used as the original strain and treated with UV and EMS for mutation.One high cellulase-producing mutant strain named E20-2 was obtained by screening with Congo red transparent zone method and shake flask fermentation.Preliminary analysis showed the optimal fermentation conditions were: wheat bran: wheat straw of 1:4,solid: liquid of 1:3～1:4,Tween-80 concentrations 0.1%,temperature 28℃,pH 6.0,cultured for 5 days.The CMCase and FPAase of the mutant strain reached 654 U/g and 69 U/g,which were 230% and 72% higher than that of the parent strain,respectively.And E20-2 had a relatively higher cellulase producing ability than ever reported.