纤维素酶高产菌株的筛选及最适产酶条件

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

从本实验室保存的57株菌株中筛选出一株可高效降解纤维素的纤维素酶高产菌株哈茨木霉APS62,其滤纸酶活力(FPA)为4.981 IU.g-1,是对照里氏木霉模式菌株APS63的3.02倍.产酶条件优化研究的结果表明,以稻草粉为底物,APS62菌株产滤纸酶的最适条件为:培养温度28℃,培养时间3 d,稻草粉与麸皮比5∶0,接种量6%,氮源为NH4NO3(总氮量0.4%),培养基起始pH为5.0,吐温80含量0.1%.此条件下的FPA为6.125 IU.g-1,比优化前提高8.10%.

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.