紫外诱变球毛壳霉选育木聚糖酶高产菌株

Breeding of xylanase producing strain with chaetomium globosum by ultraviolet mutation

木聚糖酶具有重要的潜在应用价值,为获得一株遗传性状稳定的木聚糖酶高产菌株,以木聚糖酶的酶活为评价指标,采用紫外线诱变的方法,利用单因素试验确定紫外线照射时间,通过含木聚糖的初筛培养基对紫外诱变后的菌株进行初筛,然后采用DNS法测定木聚糖酶活性对诱变菌株进行复筛。将筛选出的木聚糖酶活力最高的诱变菌株进行传代培养,测定其酶活,探讨其遗传稳定性。试验结果表明:紫外灯功率20W,照射距离30cm,照射时间120s,球毛壳霉致死率为92.35%。在此条件下进行菌株的紫外诱变获得高产木聚糖酶的正突变株15株,其中1株高产菌株Z30-56的酶活为9850IU/mL,比出发菌株提高53.7%,并且遗传性能稳定。

Xylanase has important potential applications value.In order to gain the strain which has stable genetic traits to produce xylanase,we took the xylanase activity as evaluation index,used ultraviolet mutation method,determined the time of ultraviolet irradiation by single factor experiment.By preliminary screening of Ultraviolet mutation strains in the medium containing xylan,the xylanase activity was measured by DNS methods.Screen was then repeated in the mutation strains.The highest xylanase activity mutant strains were selected to determine their activity and the genetic stability.The results of this experiment showed that the power of ultraviolet lamp was 20W,exposure distance was 30cm and exposure time was 120s.The fatality rate of chaetomium globosum was 92.35%.Under these conditions,15 mutant strains with higher yield of xylanase was selected.The strain Z30-56 had the highest xylanase activity and highest yield was 9850IU/mL,increasing 53.7% compared with the original strain.The genetics of the strain was also very stable.