Effect of Different Mutation Methods on Xylanase Production Ability by Aspergillus Niger

摘要

Based on the Aspergillus niger AS3.350, the mutants were brewed through inducing five treatments.The effect of different mutation methods on enzyme production ability of Xylanase was disscused and obtainedmutant strain of Xylanase production high ability. The results indicate that: the mutagenesis of UV irradiation and fast neutron irradiation was sensitive to increasing Xylanase activity. UV irradiation seted at 256 nm wavelength,the vertical distance was 20cm,exposure time was 90s, obtained mutant UV256-90 of the emzyme activity was 170.79U/ml,it was 2.18 times of the original strain.The rate 0.0025Gy / s of fast neutron irradiation and vertical distance 12cm,the optimal dose is 0.75Gy, screened out the mutant Fn5-2, the activity is 134.77U/ml,its 1.72 times of the original strain. Mutagenesis by diethyl sulfate, sodium nitrite, and nitrosoguanidine, enzyme activityof the optimal mutant strains were recently starting strain of 1.51 times, 1.46 times, and 1.38 times.Two physical mutagenic methods include ultraviolet mutagenesis and fast neutron irradiation were more sensitive on producing xylanase based on aspergillus Niger.