[ Objective ] High yield xylanase strains were found by screening with ultraviolet mutagenesis of Chaetoraium globosum protoplast. [ Methods ] Chaetomium globosum AS3. 3601 protoplasts were prepared under different conditions. The effect of different parameters such as enzyme concentration, temperature and time on protoplast production and regeneration rate was analyzed. The dose of UV mutagenesis was determined by single factor experiments. Xylanase activity was measured by DNS methods after initial screening and rescreening. [ Results ] Judged by combined conditions considering production rate and regeneration rate of protoplasm, the best conditions for preparing protoplast was at enzyme concentration of 1. 5% , reaction temperature of 30℃ , and time of 4h. The protoplasts treated with 60s of UV irradiation show a xylanase activity of 9980 IU /mL. [Conclusion] xylanase activity of YZ -8 with mutation strain increased 92. 6% compared with the original strain and it is genetically stability.%[目的]对球毛壳霉原生质体进行紫外诱变处理筛选出一株高产木聚糖酶菌株.[方法]实验在不同条件下制备球毛壳霉(Chaetomium globosum AS3.3601)原生质体,分析不同酶浓度、酶解温度和时间对原生质体生成率和再生率的影响,利用单因素实验确定了紫外线诱变剂量,经初筛和复筛后,DNS法测定木聚糖酶活性.[结果]结果表明:结合原生质体的生成率和再生率确定其最佳制备条件为酶浓度1.5％,酶解温度30℃,酶解时间4h,在紫外照射时间60s下处理过的原生质体,木聚糖酶活性可达到9980IU/mL.[结论]获得的诱变菌株YZ-8比原始菌株提高了92.6％,此菌株经多次传代,遗传性能稳定.
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