高产葡聚糖酶微生物的分离筛选

Isolation and Screening of Glucanase Producing Microorganisms

β-葡聚糖是饲料谷物中的主要成分之一,为了帮助动物摄取后更好的消化吸收,选择高产β-葡聚糖酶的微生物作为添加剂以提高饲料的利用率十分必要。从丁香树下土壤中分离具有产β-葡聚糖酶的微生物,通过DNS法测定其产酶活,筛选酶活较高的菌株,测定其生长曲线,并采用分子生物学方法对其进行初步鉴定。结果显示:分离得到3株高产β-葡聚糖酶的菌株,其中菌株D-1酶活力最高可以达到103.67 U·mL^(-1)。通过对该菌株的生长曲线测,得知其对数生长期在8~24 h。对其进行16S rRNA扩增并构建系统发育树,发现D-1菌株与芽孢杆菌Bacillus sp.同源性达到了99%以上,与蜡样芽孢杆菌聚为一个分支,确定该菌属于蜡样芽孢杆菌。综上,分离菌株可为高产β-葡聚糖酶微生物提供种质资源。

β-glucan is one of the main components of feed grains.In order to help animals better digest and absorb after ingestion,it is necessary to use that can produce high yieldβ-glucanase microorganisms as additives improve feed utilization.Therefore,this study isolated and screenedβ-glucanase microorganisms from the soil under the clove tree.The activity of glucanase production was determined by DNS method,and it was preliminarily identified by molecular biology method.The results showed that three strains with high yield of glucanase were isolated.The highest enzyme activity of strain D-1 was 103.67 U·mL^(-1).The growth curve of the strain showed that it's logarithmic growth period was 8-24 h.16S rRNA was amplified and phylogenetic tree was constructed.It was found that the similarity between strain D-1 and Bacillus sp.was more than 99%,and it was clustered into a branch with Bacillus cereus.It was determined that the strain belonged to Bacillus cereus.In conclusion,the isolated strains can provide germplasm resources for high-yieldβ-glucanase enzyme microorganisms.