污泥中粪大肠菌群菌值检测方法的改进

Improvement of Detection Method of Fecal Coliform Bacteria Value in Sludge

对污泥中粪大肠菌群菌值目前通用的多管发酵法进行优化。将污泥接种到乳糖胆盐发酵管,(44.5±0.5)℃培养24 h,阳性发酵管转种到EC培养液,(44.5±0.5)℃培养24 h,查MPN检索表,求倒数算出粪大肠菌群菌值,并与优化前的国标方法进行比对。结果表明,改进后的方法比国标方法减少了平板分离和染色镜检过程,缩短了检测时间,提高了检测结果的重现性,但两者在结果上无统计学意义上的差异。改进后的多管发酵法可以用于污泥中粪大肠菌群菌值的检测。

Aimed to optimize the method of fecal coliform bacteria value commonly used in the sludge detection, the sludge samples were added into lactose bile salt fermentation tube and grew for 24 h at （44.5±0.5）℃, positive fermentation tube turned to EC medium and then grew for 24 h at （44.5±0.5）℃. The results were recorded, by checking MPN retrieval table to calculate fecal coliform bacteria value by solving the inverse and compare with the national standard method before optimization. The results showed that the improved method of plate separation and staining process required less time than the international standard method and improved the reproducibility of test results. However, there was no statistically significant difference between the results of two methods. The improved technique of multiple tube fermentation was able to be adopted in the detection of fecal coliform bacteria value in sludge.