Abstract: The growth, acid production and changes in viable cell count of 8 strains of Leuconstoc mesenteroides were measured in chemically defined medium (CDM) with different carbon sources or skim milk. The results showed that there were significant differences in the growth of these strains in CDM with lactose or galactose as the single carbon source. Strains LM1, LM2, LM4 and LM8 grew well in CDM with lactose as the single carbon source. Strains LM2, LM3, LM5 and LM8 had stronger vitality in CDM with galactose as the single carbon source, but their growth was weaker than that in the presence of lactose. In skim milk, the viable cell count of all experimental strains increased obviously in the early fermentation stage. After 8 h, their growth entered the stable phase, and the pH value at the end of fermentation was above 6.0. While the differences in genes related to lactose and galactose metabolism were preliminarily compared among the strains in this study, the correlation between genes and phenotypes needs to be further analyzed based on lactose hydrolase activity and lactose and galactose residues.

Key words: Leuconstoc mesenteroides, lactose, galactose, chemical defined medium, growth characteristics

摘要： 在不同碳源的化学限定培养基（chemically defined medium，CDM）和脱脂乳中对8 株肠膜明串珠菌（Leuconstoc mesenteroides）进行培养，测定其生长、产酸及活菌数变化情况。结果表明：各菌株在以乳糖、半乳糖为单一碳源的CDM培养基中的生长情况存在明显差异，菌株LM1、LM2、LM4和LM8在以乳糖为单一碳源的CDM培养基中生长情况良好，菌株LM2、LM3、LM5和LM8在以半乳糖为单一碳源的CDM培养基中活力较强，但生长情况弱于乳糖环境；在脱脂乳环境下，实验菌株的活菌数于发酵初期明显增长，培养8 h后进入稳定期，发酵终点pH值在6.0以上；初步对比各菌株与乳糖、半乳糖代谢相关基因的差异性，基因与表现型的相关性还需结合乳糖水解酶活性及乳糖、半乳糖残留量进一步分析。

关键词: 肠膜明串珠菌, 乳糖, 半乳糖, 化学限定培养基, 生长特性