关键氨基酸对酿酒酵母高级醇代谢的影响OA北大核心CSTPCD

This study concluded that the α-amino nitrogen concentration corresponding to the lowest production of middle-and-high-level alcohol in sorghum fermentation liquor was 90 mg/L.This α-amino nitrogen concentration was regarded as the optimal amino nitrogen concentration,and then seven essential amino acids including glycine,methionine,isoleucine,threonine,valine,leucine,and trypto-phan were separately added to sorghum fermentation broth with the optimal concentrations.Finally,a comparative test on the influence of different amino acids on the metabolism of Saccharomyces cerevisiae was completed.Results showed that adding these seven amino acids to the optimal concentration of amino nitrogen had no significant effects on the fermentation rate,glucose consumption,and ethanol produc-tion of Saccharomyces cerevisiae.This study further found that the addition of methionine inhibited the production of various higher alcohols in Saccharomyces cerevisiae,the addition of tryptophan significantly improved the ability of Saccharomyces cerevisiae to synthesize phenyle-thanol,the addition of threonine significantly reduced the production of n-propanol,isobutanol,isoamyl alcohol,and phenylethanol,and significantly increased the production of active amyl alcohol.Besides,this study also found that glycine could promote the formation of higher alcohols in Saccharomyces cerevisiae at a higher α-amino nitrogen concentration.Therefore,understanding the influence of amino acids on the generation of higher alcohols in the brewing process is conducive to realize the precise regulation of products,and it also pro-vides reference value for the selection of raw materials in the brewing industry.