大曲中高产糖化酶菌株的筛选及环境耐受性分析  

Isolation of high amyloglucosidase-producing strains from Daqu and their environmental tolerance abilities

作　　者：张琳[1] 张也[1] 王如福[1] 霍乃蕊[2] 

机构地区：[1]山西农业大学食品科学与工程学院,山西太谷030801 [2]山西农业大学动物科技学院,山西太谷030801

出　　处：《山西农业大学学报（自然科学版）》2016年第10期740-744,共5页Journal of Shanxi Agricultural University(Natural Science Edition)

基　　金：山西省科技重点研发(指南)项目(2015-TN-10-2);863计划项目(2011AA1009040102)

摘　　要：[目的]分离适应酿造环境的高产糖化酶大曲土著菌株,用于大曲强化,以减少山西老陈醋酿造过程中的大曲用量,提高原料利用率并改善醋品品质。[方法]以酒精发酵24h的酒醅为样品,用Martin培养基对大曲中的霉菌进行分离,分别以透明圈和酶活大小进行初筛和复筛获得高产糖化酶菌株,以生长量为指标进行环境耐受性分析。[结果]初筛获得的10株产糖化酶菌株中M2、M5、M6、M8、M15的产酶能力（U·mL-1）高于公认的糖化酶高产菌株AS3.4309（M0）,依次为M6（3912.08（32.1）〉M5（1413.16（13.92）〉M8（1233.63（71.07）〉M15（1152.47（21.96）〉M2（923.86（22.42）〉M0（828.88（22.23）。环境耐受性分析结果表明,5株霉菌均能耐受6%的乙醇浓度,在pH3.5生长良好,有的甚至能耐受pH2.0,在15~30℃范围内均可生长。[结论]获得的5株霉菌,不仅产糖化酶能力高于公认且应用广泛的AS3.4309,还能耐受山西老陈醋的整个酿造过程。[Objective]Aboriginal mould strains with high ability to produce amyloglucosidase isolated from Daqu can be reinforced into Daqu again to lower Daqu consumption and increase the utilization rate of the material during vinegar fermentation and and improve the product quality.[Methods]The alcoholic fermenting matrix fermented for 24 hours was treated and cultured on Martin medium for mould isolation.Preliminary and second-time screening work was carried out according to the size of the transparent circle on the medium and the measured enzymatic activity.Environmental tolerant ability were evaluated through growth mass.[Results]Preliminary screening obtained 10 mould strains that can produce amyloglucosidase.The results of enzyme activity suggested that M2、M5、M6、M8and M15 were superior to the well-known high amyloglucosidase producing strain AS3.4309（M0）.Their enzyme activity（U·mL-1）were M6（3912.08（32.11）〉 M5（1413.16（13.92）〉M8（1233.63（71.07）〉M15（1152.47（21.96）〉M2（923.86（22.421）〉M0（828.88（22.23）.Tolerant ability analysis showed that all the 5strains were tolerant to 6% ethanol concentration,grew well at pH3.5,some even survived pH2.0,could grow at 15~30 ℃.[Conclusion]The obtained 5mould strains has higher ability to produce amyloglucosidase than the well-known and widely used AS3.4309 and can survive the wholeprocess of Shanxi aged vinegar fermentation.

关 键 词：山西老陈醋 酒醅 高产糖化酶菌株 环境耐受性 

分 类 号：Q939.97[生物学—微生物学]