传统曲霉型豆豉中高产脂肪酶的米曲霉筛选及鉴定

Screening and Identification of Aspergillus oryzae from the Traditional Aspergillus-Type Douchi

豆豉是中国特色四大传统大豆发酵制品之一,其中产脂肪酶菌株对豆豉风味的形成发挥着重要作用.实验对传统曲霉型豆豉发酵过程中的脂肪酶产生菌株进行了研究,以发酵过程中的曲霉型豆豉为样品,通过对其分离纯化,得到高产脂肪酶菌株8号,并测出其脂肪酶活力为30 IU·m L-1.对该菌株进行了形态学和分子生物学鉴定,通过与NCBI数据库中ITS序列比对,发现该菌株与米曲霉(Aspergillus oryzae)的相似度达100%,鉴定该菌株为米曲霉.获得的高产脂肪酶米曲霉,对豆豉的风味有重要影响,并且为后续的研究提供了依据.

Douchi is one of the four traditional fermented soybean products with Chinese characteristics,among which the production of lipase strains plays an important role in the formation of tempeh flavor.In this study,the lipase producing strain of the traditional aspergillus-type douchi is used as the sample,and the high-yield lipase strain No.8 is isolated and purified from it.The activity of the lipase is 30 IU·mL-1,and the strain is identified by morphological and molecular biology.The similarity between the strain and Aspergillus oryzae is 100%by ITS sequence comparison in NCBI database.So that the strain is identified as Aspergillus oryzae.The high yield lipase produced by Aspergillus oryzae in this experiment has a great influence on the flavor of tempeh,and provides the basis for the follow-up study.