提高酸乳中嗜酸乳杆菌活性的研究

Improving the survival of Lactobacillus acidophilus in yoghurt

从市售合生元中分离鉴定出嗜酸乳杆菌,以脱脂乳培养基或MRS液体培养基培养菌株,探讨嗜酸乳杆菌的生长特性,研究不同pH、保藏温度以及西红柿汁含量对嗜酸乳杆菌活性的影响。结果表明:嗜酸乳杆菌在pH6.5培养基中培养6h后的活菌数最大,且在pH2.5的培养基中0～2h内保持106CFU/mL以上,即能在较低的胃酸环境保持其益生作用;嗜酸乳杆菌酸乳在4℃下保藏活菌存活期较长;在脱脂乳培养基中添加西红柿汁对嗜酸乳杆菌的生长起促进作用,且以添加15%的西红柿汁效果最佳。

The Lactobacillus acidopHilus（La）were separated and identified from BIOSTIME,then cultured on skim milk or MRS liquid medium.The characters of La and the effects of different pH,preservation temperature and tomato juice addition on the survival of La were studied.The results indicated that the suitable initial pH for the survival of La was 6.5,moreover,the colony forming units of La was 106CFU/mL or more for 2 hours at pH2.5,that was,the bacteria could play their roles of probiotics.The preservation time of yoghurt containing La was longer under 4℃ than 25℃.It was found that the additions of tomato juice had an activity to promote the growths of La,furthermore,the best concentration of tomato juice was 15%.