产高聚合度IMOs右旋糖酐酶菌株Cellulosimicrobium sp.Y1的筛选及酶学性质研究  

Screening of Cellulosimicrobium Sp.Y1 Producing Dextranase with High Polymerization IMOs and Studies on Enzyme Properties

作　　者：徐颖颖 张岩 王焕宇 林倩如 苗庆珍 卢静 吕明生 王淑军 XU Yingying;ZHANG Yan;WANG Huanyu;LIN Qianru;MIAO Qingzhen;LU Jing;LYU Mingsheng;WANG Shujun(Jiangsu Key Laboratory of Marine Biological Resources and Environment,Jiangsu Provincial Key Laboratory of Marine Biotechnology,Jiangsu Ocean University,Lianyungang 222005,China)

机构地区：[1]江苏省海洋生物资源与环境重点实验室,江苏省海洋生物技术重点实验室,江苏海洋大学,江苏连云港222005

出　　处：《食品科技》2023年第3期8-16,共9页Food Science and Technology

基　　金：国家自然科学基金项目(32172154)。

摘　　要：右旋糖酐酶在制糖、医药、材料制备和生物技术等领域应用广泛。该研究从连云港羊山岛海域海泥样品中筛选分离出一株产右旋糖酐酶的菌株Cellulosimicrobium sp.Y1,对其生长、产酶条件、酶学性质以及酶解产物进行了研究:在pH7.0、温度30℃条件下生长最优。在10 g/L右旋糖酐T20、pH9.0、温度35℃条件下发酵36 h产酶量最高。该酶的最适作用温度和pH值分别为40℃和7.5。金属离子Mg^(2+)、Sr^(2+)、NH4+及低浓度的Li^(+)、Ca^(2+)、Mn^(2+)可以提高酶的活力,而Ni^(2+)、Zn^(2+)、K^(+)、Na+对该酶有不同程度的抑制作用。同时,吐温、乙醇、二甲基亚砜和尿素等有机溶剂对该酶的活力影响较小。右旋糖酐酶的分子质量约为55 ku,可以特异性地水解α-1,6糖苷键,其酶解产物中主要为异麦芽三糖和异麦芽五糖,酶解1 h的产物中,高聚合度的异麦芽五糖达到52.61%以上。该酶在食品加工和益生元的制备中具有应用前景。Dextranase is widely used in sugar production,medicine,material preparation,biotechnology and other fields.In this study,the strain Cellulosimicrobium sp.Y1 producing dextranase was screened and isolated from the sea mud of Lianyungang Yangshan island,and its growth,enzyme production conditions,enzymatic properties and hydrolysates were studied.The optimal growth conditions were pH 7.0 and temperature 30℃.The highest enzyme yield was obtained after 36 h fermentation at 10 g/L dextran T20,pH 9.0 and temperature of 35℃.The optimum temperature and pH of the enzyme are 40℃and 7.5 respectively.Metal ions Mg^(2+),Sr^(2+),NH4+and low concentrations of Li^(+),Ca^(2+),Mn^(2+)could improve the dextranase activity,while Ni^(2+),Zn^(2+),K^(+)and Na+could inhibit the enzyme.Meanwhile,the organic solvents of tween,ethanol,dimethyl sulfoxide,urea had slightly effect on the activity of the enzyme.The molecular weight of dextranase is about 55 ku,and it can hydrolyzeα-1,6 glycosidic bond specifically.The hydrolysates were mainly isomaltotriose and isomaltopentaose.After 1 h hydrolysis,the high polymerization degree of isomaltopentaose could be reached 52.61%.The dextranase has a promising application in food processing and prebiotic preparation.

关 键 词：右旋糖酐酶 Cellulosimicrobium sp 酶学性质 聚合度 异麦芽寡糖 

分 类 号：TS201.3[轻工技术与工程—食品科学]