针对酿酒酵母在乙醇发酵过程中所面临的高温、高渗透压和高浓度乙醇等环境胁迫问题,研究了乙醇发酵性能与胁迫耐性的相关性.通过对13株工业菌株和1株实验室标准菌株的发酵性能(包括菌株的生长速率、底物的消耗速率和乙醇终产量)的分析,发现这14株酵母菌可以根据其发酵性能的差异归类划分为3类.通过线性判别分析法(LDA)建立了酵母发酵性能与不同胁迫耐受能力之间的相关性;此外,引入了量化评价参数——生长抑制因子(Gi),客观地表征了不同菌株的胁迫耐受能力.基于该胁迫耐受能力并结合LDA建立了预测菌株发酵性能的统计学模型,为酿酒酵母的培育和筛选提供了一种新的评价方法.
In the process of ethanol fermentation, Saccharomyces cerevisiae usually encounters various stress conditions, such as high temperature, high osmotic pressure and high-concentration ethanol. Aiming at these problems, the relationship between the fermentation behavior and the stress tolerance is investigated. In the investigation, the fermentation behaviors of thirteen industrial and one laboratory trial yeast strains, including the growth rate, the substrate consumption rate and the ethanol yield, are analyzed. It is found that these strains can be classified into three groups based on their fermentation behaviors. Moreover, a correlation between the fermentation behavior and the tolerance to various stresses is set up by means of the linear discriminant analysis ( LDA), and a growth inhibitor (Gi) is used as a quantitative parameter to evaluate the stress tolerance of different strains. Finally, based on the tolerance and the LDA method, a statistical model is established to predict the fermentation behaviors of the strains, which lays down a novel evaluation method for the breeding and selection of S. cerevisiae.