产纤维素酶酵母菌的筛选及鉴定

Screening and identification of cellulase producing strains

研究旨在筛选出产纤维素酶较高的酵母菌,并对其生物学特性探讨。试验从生境中筛选到产纤维素酶较高一株酵母菌,通过菌株形态学和分子生物学对该菌株进行了鉴定,并对这株菌的耐酸性、耐模拟肠液性、产酶特性和抑菌能力进行评定。结果表明,所筛酵母菌Y3为酿酒酵母菌,产纤维素内切葡聚糖酶酶活为3.27 U/ml,纤维素外切葡聚糖酶酶活为2.22 U/ml,木聚糖酶酶活为4.21 U/ml,耐酸性、耐模拟胃液较强,而耐模拟肠液能力较弱,不能产生抗金黄色葡萄球菌的物质。试验筛选到酿酒酵母菌Y3是一株较高产纤维素酶菌株并具有良好的生物学特性,对于提高粮食加工副产物的利用率具有非常重要的现实意义。

This experiment was conducted to screen a high cellulose producing yeast strain and studyits biological characteristics. In this research, a yeast strain that produces more cellulose were isolatedfrom habitats.We identified this strain based on morphological features and molecular biology features.Then acid resistance, simulated small intestine fluid resistance, cellulose activity and antimicrobial ac-tivity were determined. The results showed that ： strain Y3 was a Saccharomyces cerevisiae with strongacid resistance and artificial gastric acid resistance but poor small intestine fluid resistance. The endo-glucanase activity, exoglucanase activity and xylanase activity of the fermented corn fiber and soybeandregs were 3.27 U/ml, 2.22 U/ml and 4.21 U/ml, respectively. Moreover, this strain showed no inhibito-ry activity against Staphylococcus aureus. These results indicated that Accharomyces cerevisiae Y3 can produce high yield of cellulose and has good biological characteristics. This research shows greatvalue in improving the utilization rate of food processing by-products.