乳酸菌计数结果的比较研究

Comparative study on counting results in Lactobacillus counting method

通过流式细胞术(FCM),利用SYTO?24与PI双染色对发酵乳制品即发酵乳饮料和发酵乳中的乳酸菌进行快速检测,并将检测结果与用现行国标中推荐的平板计数法检测得到的结果相比较,两者对发酵乳饮料和发酵乳中乳酸菌的计数结果的相关性系数分别为:0. 9014;和0. 9653,都符合较好.而且FCM稳定性更好,活性细菌的变异率为3. 46%,非活性细菌的变异率为3. 56%;检测速度更快,单样品检测时间不超过10 min;灵敏度更高(10~3AFU·mL^(-1)) FCM在需要快速放行的液体产品检测领域中具有广阔的应用前景.

By using flow cytometry method (FCM) and SYTO■24 and PI double staining,the lactic acid bacteria in fermented milk products,fermented milk beverage and fermented milk were quickly detected.And the results are compared with those of the plate counting method recommended in the current national standard.The results showed that the correlation coefficient of the count of lactic acid bacteria in fermented milk beverage detected by two methods was P=0.9014.The correlation coefficient of the count of lactic acid bacteria in fermented milk detected by two methods was P=0.9653.It was in good agreement with each other.And the stability of flow cytometry was good,the coefficient of variation(CV) of active bacteria was 3.46%,and the CV of inactivated bacteria was 3.56%.The detection speed is fast,the single sample detection time is not more than 10 minutes,and the sensitivity is higher (10^3 AFU·mL^-1 ).It can be seen that this method has broad application prospects for liquid products that need rapid release.