Screening of a high cellulase producing strain and the study on the optimum conditions for cellulase production

A high cellulase producing strain of APS62 that can efficiently degrade cellulose was screened from 57 strains stored in our lab,the cellulase activity was 4.981 IU·g-1 which was 3.02 times as high as APS63(control).The results showed that the optimum conditions that APS62 produces filter paper enzyme with rice straw as the substrate were culture temperature 28 ℃,incubation time 3 d,straw powder and wheat bran ratio 5∶0,inoculation ratio 6%,NH4NO3 as nitrogen source(the amount of total nitrogen 0.4%),the initial pH 5.0,Tween-80 concentration 0.1%.Under these conditions,the filter paper activity was 6.125 IU·g-1,increasing 8.10% than that prior to optimization.