宁波地区传统梅干菜中优势发酵菌株分离鉴定及酶活分析

Isolation,Identification and Enzyme Activity Analysis of Dominant Fermentation Strains from Traditional Pickled and Dried Mustard in Ningbo

以宁波地区梅干菜半成品和成品为试验材料,采用十倍稀释法分离其中优势发酵菌株,从半成品中得到7株细菌,分别命名为MGCB1~MGCB7,从成品中得到3株细菌,分别命名为MGC1~MGC3。通过形态学观察、生理生化试验及16S rRNA序列分析对菌种进行鉴定,结果表明,MGCB1~MGCB7分别为枯草芽孢杆菌属(Bacillus subtilis)、空气芽孢杆菌属(Bacillus aerius)、高山芽孢杆菌属(Bacillus altitudinis)、短小芽孢杆菌属(Bacillus pumilus)、琥珀葡萄球菌属(Staphylococcus succinus)、琥珀葡萄球菌属(Staphylococcus succinus)和解淀粉芽孢杆菌属(Bacillus amyloliquefaciens),MGC1~MGC3分别为芽孢杆菌属(Bacillus sp.)、枝芽孢杆菌属(Virgibacillus halodenitrificans)、哥特氏芽孢杆菌属(Cytobacillus gottheilii)。MGCB1和MGCB7产酶能力相对较高,在37℃培养96 h后,蛋白酶活分别为16.39±0.79和13.45±0.46 U/mL,纤维素酶活分别为3.27±0.13和1.60±0.02 U/mL。研究结果可为梅干菜纯种发酵剂的开发及工业化生产提供有益参考。

With the semi-finished and finished products of pickled and dried mustard in Ningbo as experimental materials,the dominant bacteria strains were isolated by ten-fold dilution method.The results showed that seven and three bacteria were obtained from the semi-finished and finished products,respectively,which were named as strain MGCB1~MGCB7 and strain MGC1~MGC3.The ten strains were identified by morphological observation,physiological and biochemical tests,and 16S rRNA sequence analysis.They were likely belong to Bacillus subtilis(MGCB1),Bacillus aerius(MGCB2),Bacillus altitudinis(MGCB3),Bacillus pumilus(MGCB4),Staphylococcus succinus(MGCB5),Staphylococcus succinus(MGCB6)and Bacillus amyloliquefaciens(MGCB7),Bacillus sp.(MGC1),Virgibacillus halodenitrificans(MGC2),and Cytobacillus gottheilii(MGC3),respectively.The protease activities of MGCB1 and MGCB7 were 16.39±0.79 and 13.45±0.46 U/mL,and the cellulase activities of MGCB1 and MGCB7 were 3.27±0.13 and 1.60±0.02 U/mL,respectively,after cultured at 37℃for 96 h.These findings provide a useful reference for developing appropriate starter cultures to improve the quality of traditional pickled and dried mustard.