一株耐酸高酯化力细菌的鉴定及发酵条件研究

Identification of an Acid-Tolerant Bacteria Strain with Strong Esterifying Power and Study of Its Fermenting Conditions

将1株从郎酒酒糟中筛选得到的耐酸产酯香细菌ZP-28采用分子生物学鉴定,根据该菌株的16S rRNA序列分析结果,显示该菌株为枯草芽孢杆菌(Bacillus subtilis)。以该菌株为出发菌株,分别从温度、接种量、培养时间3方面设计单因素实验研究发酵条件,在单因素实验基础上采用正交法设计实验对ZP-28发酵条件进行优化。正交实验结果显示,接种量对酯化力的影响最大,其次是培养温度,对酯化力影响最小的是培养时间。最终确定在培养温度37℃,培养时间72 h,接种量为2%的条件下得到的麸曲的酯化力较高。

In this study,acid-tolerant bacteria strain ZP-28with strong esterifying power was isolated from distillers grains of Langjiu.16S rRNA sequencing analysis revealed such strain was Bacillus subtilis.This strain was used as the starting strain,and single factor test was performed from three aspects including temperature,inoculating quantity,and culture time to explore its fermenting conditions,then orthogonal experiments were carried out to optimize its fermenting conditions.The orthogonal results showed that the inoculating quantity had the maximum influence on the esterifying power,then followed by culture temperature and culture time.The best fermenting conditions were summed up as follows:culture temperature was at37℃,culture time was72h,and the inoculation quantity was2%.