| Summary: | The spontaneous fermentation of alcoholic beverage is a bioprocess donated by microbiota with complex stress environments. Among various microbes, non-<i>Saccharomyces</i> yeasts have high stress tolerance and significantly affect the taste and quality of products in process. Although many researchers have focused on the influence of acid stress, the mechanism of non-<i>Saccharomyces</i> yeasts to tolerant stress remains unclear in microbiota. To bridge the gap, we constructed in situ and in vitro studies to explore the reduction pathway of acetic acid in non-<i>Saccharomyces</i> yeasts. In this study, we found <i>Schizosaccharomyces pombe</i> has special capacities to resist 10 g/L acetic acid in laboratory cultures and decrease the average concentration of acetic acid from 9.62 to 6.55 g/kg fermented grains in Chinese Maotai-flavor liquor (<i>Baijiu</i>) production. Moreover, <i>Schi. pombe</i> promoted metabolic level of mevalonate pathway (high expressions of gene <i>ACCAT1</i>, <i>HMGCS1,</i> and <i>HMGCR1</i>) to degrade a high concentration of acetic acid. Meanwhile, <i>Schi. pombe</i> also improved the concentration of mevalonic acid that is the precursor of terpenes to enhance the taste and quality of <i>Baijiu</i>. Overall, the synchronicity of reduction and generation in <i>Schi. pombe</i> advances the current knowledge to guide more suitable strategies for mechanism studies of non-<i>Saccharomyces</i> yeasts in fermented industries of alcoholic beverages.
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