3、 The most probable number method(液体稀释法) 主要适用于只能进行液体培养的微生[n 95% Confidence MPN Index/ 物,或采用液体鉴别培养基进行直接【0 100ml Lower 鉴定并计数的微生物 273 12 15 4-4-0 Volume of Inoculum for Tubes of Nutrient Medium Number of Positive 5-0-0 Each Set of ( Sets of Five Tubes) 50-1 Five Tubes Tubes in Set mn日目目日 5-2-0 50 0日 2000000 222 0.1ml 5-3-1 110 5-3-2 Figure 6.18 The most probable number(MPN) method. In this example, there are three sets of tubes and five tubes in each set. Each tube in the first set of five tubes receives 10 ml of the inoculum, such as a sample of water. Each tube in the second set of five tubes receives I ml of the sample, and the third set, 0. 1 ml each. There were enough bacteria in the sample that all five tubes in the first set showed bacterial growth and were recorded as positive. In the second set, which received only one-tenth as much inoculum, only three tubes were positive. In 对未知样品进行十倍稀释,然后根据估算取三个连续的稀释度 平行接种多支试管,对这些平行试管的微生物生长情况进行统 计,长菌的为阳性,未长菌的为阴性,然后根据数学统计计算 出样品中的微生物数目3、The most probable number method（液体稀释法） 主要适用于只能进行液体培养的微生 物，或采用液体鉴别培养基进行直接 鉴定并计数的微生物。 对未知样品进行十倍稀释，然后根据估算取三个连续的稀释度 平行接种多支试管，对这些平行试管的微生物生长情况进行统 计，长菌的为阳性，未长菌的为阴性，然后根据数学统计计算 出样品中的微生物数目