酒酒球菌β-葡萄糖苷酶产酶条件优化及酶学性质研究  

Optimization of β-glycosidase production of Oenococcusoeniand its enzymology properties

作　　者：王玲[1] 卜潇 陈其玲[1] 宋巧智 刘树文[1,2,3] 

机构地区：[1]西北农林科技大学葡萄酒学院,陕西杨凌712100 [2]陕西省葡萄与葡萄酒工程技术研究中心,陕西杨凌712100 [3]西北农林科技大学合阳葡萄试验示范站,陕西合阳715300

出　　处：《西北农林科技大学学报（自然科学版）》2017年第5期130-138,共9页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家"十二五"科技支撑计划项目(2012BAD31B07);现代农业产业技术体系建设专项(nycytx-30-ch-03)

摘　　要：【目的】优化酒酒球菌中β-葡萄糖苷酶的产酶条件,分析β-葡萄糖苷酶的性质,为将其应用于葡萄酒生产提供参考。【方法】对12株酒酒球菌进行β-葡萄糖苷酶活性测定,选择其中β-葡萄糖苷酶活性最高的菌株CS-7b作为试验菌株,并以商业菌株31-DH为对照,以菌株催化底物对硝基苯酚-β-葡萄糖苷(p-NPG)生成对硝基苯酚的速度衡量β-葡萄糖苷酶活性高低。然后通过单因素试验和正交试验对菌株产β-葡萄糖苷酶的条件进行优化,并探究葡萄酒环境相关因素(pH值、温度、乙醇体积分数、葡萄糖质量浓度)对β-葡萄糖苷酶活性的影响。【结果】单因素试验确定菌株产β-葡萄糖苷酶培养基的最佳pH值为6.8,最佳碳源为麦芽糖,最佳氮源为酵母浸粉,正交试验进一步确定了各种成分的最佳配比,即每升液体培养基中含麦芽糖7g,酵母浸粉20g,MgSO_4·7H_2O 0.1g,盐酸半胱氨酸0.5g,MnSO_4·4H_2O 0.03g,培养基起始pH值为6.8,在此条件下,β-葡萄糖苷酶活性可由0.359增加到1.319μmol/(g·min)。β-葡萄糖苷酶的酶学性质为:最适pH值为5.0,最适温度为37℃;当乙醇体积分数大于4%、葡萄糖质量浓度大于1g/L时,β-葡萄糖苷酶活性开始受到抑制。【结论】酒酒球菌CS-7b在葡萄酒环境的pH及乙醇体积分数条件下仍可保持一定的β-葡萄糖苷酶活性。[Objective] This study optimized theβ-glycosidase production and characterized its enzymol- ogy properties to provide basis for its application in wine-making. [Method] Oenococcus oeni CS-Tb was se- lected among twelve tested strains because of its highest enzyme activity. The commercial strain 31-DH was used as control. The enzyme activity was measured according to the production rate of p-nitrophenol （p- NP） with p-nitrophenyl-β-glucoside （p-NPG） as the substrate. The enzyme production conditions were op- timized by single factor experiment and orthogonal experiment. The effects of environment factors （pH, temperature, alcohol and glucose content） were also investigated. [Result] Single factor experiment showedthat the best conditions were pH value 6.8, carbon source maltose, and nitrogen source yeast powder. Then orthogonal experiment determined the best amounts： 1 L medium should contain 7 g maltose as carbon source,20 g yeast extract as nitrogen source,MgSO4 · 7H2O 0.1 g,cysteine hydrochloride 0.5 g,MnSO, · 4H2O 0.03 g, and initial pH 6. 8. Under optimal conditions, the enzyme activity was increased to 1. 319 μmol/（g ·min） from the initial of 0. 359 μmol/（g · min）. Enzymology properties were：β-glycosidase was optimal at pH 5.0 and 37 ℃ and the activity was strongly inhibited by higher concentrations of alcohol （4 %） and glucose （1 g/L）. [Conclusion] Strain CS-7b retained high glycosidase activity under wine condi- tions of p potential

关 键 词：酒酒球菌 Β-葡萄糖苷酶 产酶条件优化 酶学性质 

分 类 号：S663.1[农业科学—果树学] TS261.1[农业科学—园艺学]