原料乳中耐冷菌群及其产酶特点  

Biodiversity of Psychrotrophic Bacteria Isolated from Raw Milk and Their Enzymatic Profiles

作　　者：徐煜[1] 刘振民[1] 游春苹[1] XU Yu LIU Zhenmin YOU Chunping(State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co. Ltd., Shanghai 200436, Chin)

机构地区：[1]乳业生物技术国家重点实验室,上海乳业生物工程技术研究中心,光明乳业股份有限公司乳业研究院,上海200436

出　　处：《乳业科学与技术》2017年第1期1-8,共8页JOURNAL OF DAIRY SCIENCE AND TECHNOLOGY

基　　金：“十二五”国家科技支撑计划项目(2012BAD12B08);上海市科委优秀技术带头人计划项目(15XD1520300)

摘　　要：耐冷菌及其分泌的耐热酶是原料乳中常见污染物,会导致乳制品腐败。通过16S r RNA基因测序分析了分离自上海地区原料乳的耐冷菌群,以及通过平板法研究不同耐冷菌的蛋白酶和脂肪酶活力。结果表明:所有的分离株属于9个菌纲,含33个菌属,其中数量占主要的菌属是假单胞菌(Pseudomonas)(55%)、不动杆菌(Acinetobacter)(10%)和黄杆菌(Flavobacterium)(5%),其余30个菌属占所有菌株数的30%。耐冷菌产酶能力平板法实验显示,大部分的耐冷菌都有产蛋白酶或脂肪酶的能力,不同菌属之间产酶特点存在差异。假单胞菌和黄杆菌主要表现为产蛋白酶活性,克雷伯氏菌(Klebsiella)主要表现为产脂肪酶活性,而大多数的不动杆菌没有产蛋白酶或脂肪酶活性。Psychrotrophic bacteria and their heat-resistant enzymes are common contaminants in raw milk, leading to dairy product spoilage. The biodiversity of psychrotrophic bacteria isolated from raw milk in Shanghai was investigated by 16 S r RNA sequencing and the individual isolates were evaluated for protease and lipase activities by plate culture. All isolates were classified into 33 genera in 9 classes, with Pseudomonas（55%）, Acinetobacter（10%） and Flavobacterium（5%） being predominant, and the remaining 30 genera accounting for 30% of the total number of isolates. Most isolates had the ability to produce protease or lipase, and different genera had different enzymatic profiles. Pseudomonas and Flavobacterium exhibited considerable protease activity, whereas Klebsiella showed strong lipase activity. On the other hand, most Acinetobacter isolates could produced neither protease nor lipase.

关 键 词：耐冷菌 蛋白水解 脂肪水解 假单胞菌 黄杆菌 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]