Indigenous Saccharomyces cerevisiae KDLYS9-3 produces high activity beta-D-glucosidase, and it has the effect of enhancing aroma during the wine making process. Based on the experiment of bacteria growth and enzyme production, the Logistic equation, DoseResp equation and Nelder equation were used to build a dynamic model for the yeast growth and enzyme production, and the relationship of yeast growth rate and en-zyme producing rate in this study. After the nonlinear fitting by Origin 8.0 software, and graphed by the method of Lineweaver-Burk, the kinetic parameters of Km and Vmax values for the enzymes of this yeast producing beta-D-glycosidase were detected. The result shows that the bacteria growth and enzyme production dynamic model of KDLYS9-3 were correlation with the test results, the dynamic model equation can reflect the variety regula-tion of bacteria growth and enzyme production, the correlation was part of the coupling relationship. The yeast began to produce enzymes after 8 h growth, and it produced a large number of enzymes when entered the loga-rithm of growth. The growth of yeast was stable after 39 h. With the decline phase of the yeast, the enzyme also stopped producing. The kinetic parameters of the KDLYS 9-3 enzyme were obtained by the double reciprocal method. The Km was 8.492579 mmol/L, and the Vmax was 1.030715 (mu/L)/min. The results helped set the basement of the strains'theoretical foundation and practical application.%自选高产β-D-葡萄糖苷酶的酿酒酵母(KDLYS9-3)在葡萄酒酿造过程中具有增强香气的效果.依据菌体生长和产酶试验,利用Logistic方程、DoseResp方程和Nelder方程建立了菌体生长和产酶,以及菌体生长速率与酶生成速率之间关系的动力学模型,通过Origin8.0软件进行非线性拟合,并利用Lineweaver-Burk法作图测定了该菌所产β-D-葡萄糖苷酶的动力学参数Km值和Vmax值.结果显示:自选酿酒酵母KDLYS9-3的菌体生长与产酶的相关性为部分偶联型,动力学模型与试验值吻合度好,方程能够反映菌体生长与产酶的变化规律.菌体生长8h后开始产酶,菌体进入对数生长期时酶大量生成,到39 h菌体生长进入稳定期,随着菌体生长进入衰亡期后酶也随之停止产生;利用Lineweaver-Burk法求得酶动力学参数Km=8.492579 mmol/L,Vmax=1.030715(μmol/L)/min.研究结果为该菌株的理论研究和实际应用奠定了基础.
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