梅奇酵母氨基甲酸乙酯酶分离纯化与酶学性质分析及其对葡萄酒香气的影响

孟凡徳; 史学伟

doi:10.13386/j.issn1002-0306.2021110279

梅奇酵母氨基甲酸乙酯酶分离纯化与酶学性质分析及其对葡萄酒香气的影响

Isolation, Purification and Characterization of Ethyl Earbamate Degrading Enzyme from Metschnikowia and Its Effect on Wine Aroma

摘要

摘要: 为了研究梅奇酵母所产生氨基甲酸乙酯（Ethyl Carbamate，EC）酶的性质，通过硫酸铵盐析、离子交换层析的方法对EC酶进行分离纯化，并对纯化后EC酶的酶学性质进行了分析。结果表明，纯化后EC酶对比纯化前的酶活提高了约1.2倍。纯化后EC酶最适反应温度为35 ℃，在25~45 ℃之间热稳定性较强；最适pH为5.5，在pH5~6时该酶稳定性强，即酸稳定性强，碱稳定性较差。当乙醇体积分数为12%~14%时，EC酶具有一定酶活。底物特异性结果表明，该EC酶对EC及其前体物质（尿素）具有较高的降解能力，且对于成品葡萄酒挥发性香气成分影响不显著。

Abstract: In order to study the properties of Ethyl Carbamate (EC) enzyme produced by Metschnikowia, the EC enzyme was separated and purified by ammonium sulfate salting out and ion exchange chromatography, and the enzymatic properties of the purified EC enzyme were analyzed. The results showed that the activity of EC enzyme after purification was about 1.2 times higher than that before purification. The optimal reaction temperature of the purified EC enzyme was 35 ℃, and the thermal stability was strong between 25 and 45 ℃. The optimal pH was 5.5, and the enzyme had strong stability at pH5~6, that was, the acid stability was strong, and the alkali stability was poor. When the volume fraction of ethanol was 12%~14%, EC enzyme still had some enzyme activity. The substrate specificity results showed that the EC enzyme had a high degradation ability on EC and its precursor (urea), and had no significant effect on the volatile flavor substances of the finished wine.