In order to enhance the caproicacid productionof Clostridium kluyveri and shorten thefermentation period,this strain was co-colturedwith Saccharomyces cerevisiae and themechanism of enhancing caproic acid production in the mixed culture system was furtherly analyzed. Studies have revealed that:caproicacid yieldin the fermentation tank with pure colture of Clostridium kluyveri reached 6.35 g/L. However,caproic acid production with co-cultured system reached 7.09 g/L,which was 12.5% higher than that of the pure culture system and thetime reaching peak of caproic acid production was shortenedfor approximately 48 h. Relative data indicated that when co-culture wit Saccharomyces cerevisiae,thecaproic acid production of Clostridium kluyveriwas improved byincreasing the conversion rate of acetic acid to butyric acid. Analysis of dissolved oxygen values and microbial growth parameters indicated that the main reason for this change was that the growth of Saccharomyces cerevisiae improved the anaerobiclevel of co-culture system,which promoted the formation and transformation of butyric acid,hence the caproic acid production was enhanced.%为了提高克氏梭菌8022产己酸的能力,缩短发酵周期,作者将该株菌与酿酒酵母进行了混合培养,并进一步分析混合培养体系提高己酸产量的机理.研究表明:在用发酵罐对己酸菌进行纯培养时己酸菌产量可达6.35 g/L,与酿酒酵母共培养时,产酸达到7.09 g/L,产酸提高了12.5%,且到达最大产酸的周期缩短了约48 h.相关参数的分析表明,酿酒酵母在共培养过程中主要通过提高乙酸到丁酸的转化速率,从而提高己酸的产量.通过分析溶氧值和微生物生长参数,表明引起这一变化的主要原因是共培养时酿酒酵母的生长提高了共培养体系的厌氧水平,促进丁酸的生成和转化,从而提高了己酸的产量.
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