米曲霉固体发酵过程中的动力学

On the Kinetics of Aspergillus oryzae in Solid State Fermentation

对米曲霉固体发酵生产酱油过程中各阶段的微生物动力学行为进行了研究,应用动力学的概念对所建立的菌种筛选模型进行了解释.种子生长和发酵阶段的研究结果表明:碳源是米曲霉产孢子的速率限制性底物,种子阶段孢子对残总糖的产率系数为YX/S=2.428×1010个/g,最大比生长速率μmax=5.28d-1,产孢子的最大比生长速率与温度之间的关系呈钟罩形.同时建立了产孢子速率与水分含量的关系以及产酶速率与水分之间的关系.在发酵过程中发现了米曲霉的二次生长现象,该现象出现的时间随不同的底物比例发生迁移.

To reveal the dynamic behavior of Aspergillus oryzae in solid state fermentation, the solid fermentation kinetics of Aspergillus oryzae for different soy sauce production stages were studied, and the model for screening strains was established and then interpreted based on the kinetics obtained. The results showed that carbon source is a ratelimiting substrate for spore producing, the yield coefficient of spores to the total sugar are 2.428×1010 spores/g and the maximal specific growth rate at the seed growth state, 5.28 d-1 respectively. The relationships between the different speed parameters and operating conditions were also established. The second growth phenomenon of Aspergillus oryzae during the fermentation stage was discovered. The occurrence time of the second growth changed with the different substrate ratio.