【作者】 黄琴；

【导师】 武波；

【作者基本信息】 广西民族大学 ， 生物化学与分子生物学， 2012， 硕士

【摘要】 β-葡萄糖苷酶作为催化水解糖苷键的催化剂广泛来源于动植物、微生物中，且应用于食品、工业、医药等行业，对其研究具有一定的理论和实用价值。基于活性分离筛选策略，本研究得到了具有生化性质优势的﹑产β-葡萄糖苷酶速度快的WGEA1菌种,将其初步鉴定为微小杆菌Exiguobacterium sp；又经发酵条件的优化得到了最优发酵条件，由原先的酶活3.62U/ml提高至25.34U/ml；进一步测其酶活特性，发现Exiguobacterium sp. WGEA1产酶最适温度为55℃，最适pH为8，且在50℃以下，pH5~8的条件下酶活比较稳定；金属离子中的Ba2+、Cu2+、Mn2+的激活作用最强相对酶活达150％以上，而Al3+、K+的抑制作用也最为强烈，残余酶活在50％以下；有机溶剂丙酮作为增强剂来增强酶活，但是甲醇、乙醇、乙酸乙酯等却抑制了该酶的活性；除此外，在pH为5的环境下，以该酶为催化剂，初步地利用薄层分析(TLC)的方法对催化合成的产物进行了分析。经过对Exiguobacterium sp. WGEA1菌种快速度产酶的研究和定性分析了发酵液的催化结果，为下一步深入研究Exiguobacteriumsp.WGEA1产酶在非水相体系中的催化效率奠定了基础，也为加以继续研究目标菌株的其他生化性质奠定了基础，因而具有良好的应用前景。更多还原

【Abstract】 β-glucosidase has derived from plants﹑animals and microbes, as abiocatalyst which hydrolysis glycosidic bonds, has been widely used infood, industrial, pharmaceutical and other industries, and its research hasa certain theoretical and practical value.Basing on the strategy of the acticity isolation, this study getWGEA1strain that had the advantages of the biochemical properties andproduced the enzyme β-glucosidase fast, it was screened and identifiedas Exiguobacterium sp preliminarily；Preliminary optimized fermentationconditions to get the optimum fermentation conditions, from the originalactivity3.62U/ml to25.34U/ml; further estimated its enzymaticproperties, found that WGEA1enzyme production optimum temperatureand pH were55℃and8, below50℃, the activity was relatively stableunder the conditions of pH5~8; Metal ions of the Ba2+and Cu2+, Mn2+had the more stronger relative activity that were more than150%,but Al3+and K+that had the most strongest inhibition, the residual activity werelower than50%; Organic solvents acetone as a reinforcing agent toenhance the activity, but methanol, ethanol and ethyl acetate inhibited theenzyme activity; In addition, in the environment of pH5, the enzyme as acatalyst, TLC analyzed catalytic synthesis of products preliminarily.The research that Exiguobacterium sp. WGEA1producedβ-glucosidase and analyzed the catalytic results of the fermentation brothqualitatively, it laid thebasis for in-depth study of the enzyme catalyticefficiency from Exiguobacterium sp.WGEA1in the non-aqueousphase,laid the foundation to continue to study the biochenmical propertiesof the target strains,and thus it will have a good application prospect.更多还原