指数补料发酵提高鲁氏酵母β-1,3-葡聚糖酶产量

Enhancement of β-1,3-glucanase Production in Salt-tolerant Zygosaccharomyces rouxii by Exponential Fed-batch

摘要:

高耐盐鲁氏酵母A菌株（耐24%盐）10 L发酵罐产β-1,3-葡聚糖酶的过程中，葡萄糖（YEPD）是鲁氏酵母A生长和产酶的最适碳源，其发酵效率显著高于甘油（YEPG）和乙醇（YEPE），而乙酸钠的可利用性较差。YEPD批培养生长效率（生物量）、最大酶活力以及酶产率分别比YEPG和YEPE批培养提高了1.89%和29.88%、114%和19.65%以及188%和33%。与YEPD批培养相比，15~23 h开始指数流加YEPF培养基，达到最大生物量的周期缩短12 h，最大生物量提高19.29%，而且β-1,3葡聚糖酶几乎以对数增长的方式提前6 h合成到最大酶活力（44.99 U/mL），酶产率提高了76.86%，达到2.14 U/(mL?h)，实现了指数补料发酵的目的。研究结果确定了有效提高鲁氏酵母A生物量和?-1,3-葡聚糖酶产量的指数补料模型，为高耐盐鲁氏酵母菌剂和β-1,3-葡聚糖酶产品有效生产以及其在高活性酿造功能食品行业的应用打下了基础。

Abstract:

High salt-tolerant Zygosaccharomyces rouxii A (tolerant of 24% NaCl) was used to produce ?-1,3-Glucanase in 10 L fermenter. Glucose (YEPD) is the optimum carbon source for yeast growth and enzyme production. Fermentation efficiency with YEPD batch culture is significantly higher than that with glycerol (YEPG) and ethanol (YEPE), respectively. Meanwhile, batch culture efficiency with acetate as carbon source was poor. The growth efficiency (biomass), the largest ?-1,3-Glucanase and enzyme productivity with YEPD batch cultivation was increased by 1.89% and 29.88%, 114% and 19.65%, 188% and 33% than that with YEPG and YEPE batch culture, respectively. Compared with the YEPD batch cultivation, exponential fed-batch with YEPF medium from 15 to 23 h, the time of maximum biomass was shorten by 12 h and the maximum biomass was increased by 19.29%. Moreover, ?-1,3-glucanase was nearly logarithmically synthesized to the largest enzyme activity (44.99 U/mL), the time of synthesis was shortened by 6 h and enzyme productivity was up to 2.14 U/(mL?h) that was increased by 76.86%. Exponential fed-batch model for effective enhancement of biomass and β-1,3-glucanase production by Z. Rouxii A was confirmed by the results above, which laid the foundations for the effective production of high salt-tolerant Z. Rouxii A, ?-1,3-glucanase products and the application of them in highly active fermentative function food industry.