精品文档---下载后可任意编辑产 L-乳酸嗜碱菌的筛选及发酵条件优化的开题报告摘要:本文旨在通过筛选优良的 L-乳酸嗜碱菌株,并优化其发酵条件,以最大程度提高其产酸性能。首先,从不同环境样品中分离出乳酸菌,并通过酸碱指示纸筛选出嗜碱性乳酸菌株;随后,通过生理生化实验及16S rRNA 序列分析,确定了最优菌株为嗜碱性乳酸菌 BAB-52,并讨论了不同培育基、pH 值、培育温度和培育时间等发酵条件对该菌株产酸性能的影响。结果表明,选用 LBS 培育基、pH 值 10.0、培育温度 37℃、培育时间 48h 时,BAB-52 菌株的最大乳酸产量可达到 5.96g/L。本讨论结果为开展乳酸菌及相关产物的生产提供了一定的理论参考和实验基础。关键词:L-乳酸嗜碱菌;筛选;发酵;产酸性能;优化Abstract:The objective of this study was to screen excellent L-lactic acid alkalophilic bacteria strains and optimize their fermentation conditions to maximize their acid-producing ability. Firstly, lactic acid bacteria were isolated from different environmental samples, and alkalophilic lactic acid bacteria strains were screened by acid-base indicator paper. Then, through physio-biochemical experiments and 16S rRNA sequence analysis, the optimal strain was determined to be the alkalophilic lactic acid bacteria BAB-52, and the effects of different fermentation conditions such as culture medium, pH, temperature and fermentation time on the acid-producing ability of the strain were studied. The results showed that when using LBS medium, pH value of 10.0, culture temperature of 37℃ and culture time of 48h, the maximum lactic acid production of BAB-52 strain could reach 5.96g/L. The results of this study provide a certain theoretical reference and experimental basis for the production of lactic acid bacteria and related products.Keywords: L-lactic acid alkalophilic bacteria; screening; fermentation; acid-producing ability; optimization.