检测沙门菌的微量半固体氯化镁孔雀绿最可能数方法研究

Quantitative analysis of foodborne Salmonella - the study of mini-modified semi solid rappaport vassiliadis most probable number method

目的改良检测沙门菌的微量半固体氯化镁孑L雀绿最可能数（mini—MSRVMPN）方法。方法在mini．MSRVMPN方法的基础上，将缓冲蛋白胨水（BPW）改为一步增菌液，MSRV培养基改为改良MSRV培养基，进行沙门菌加标回收试验。分别采集154份生鸡肉、48份鸡舍环境涂抹物和48份鸡粪样品，对比分析改良mini—MSRVMPN法、mini—MSRVMPN法和常规最大可能数（MPN）方法检出沙门菌的情况。结果改良mini—MSRVMPN方法加标回收试验结果：0．9CFU／g加标菌量组回收菌量均〈2．7MPN／g；9．0、90．0CFU／g加标菌量组平均回收菌量分别为10．1、94．0MPN／g，平均回收率分别为112％、104％。改良mini—MSRVMPN方法、mini—MSRVMPN方法和常规MPN方法沙门菌检出率分别为18．4％（46／250）、5．2％（13／250）和6．0％（15／250），改良mini—MSRVMPN方法检出率高于其他两种方法（×。值分别为19．68和17．82，P值均〈0．05）；检出沙门菌的量（中位数）分别为21．0、〈2．7、〈3．0MPN／g，改良mini—MSRVMPN方法检出沙门菌的量（中位数）高于其他两种方法（z值均为5．71，P值均〈Q05）。结论改良mini—MSRVMPN方法可以对食源性沙门菌进行准确检测。

Objective To improve the mini-modified semi solid rappaport vassiliadis most probable number （ mini-MSRV MPN ） method for Salmonella detection. Methods Based on the mini-MSRV MPN method, Buffered Peptone Water （BPW） was modified as one step enrichment medium and Modified Semi Solid Rappaport Vassiliadis （MSRV） medimn was ameliorated as modified MSRV for Salmonella detection under standard Salmonella addition recovery. A total of 154 raw chicken samples ,48 swabs of pheasantry and 48 poultry dung samples were collected to compare the detection results of Salmonella by using improved mini-MSRV MPN, mini-MSRV MPN and regular most probable number （ MPN ） method. Results Salmonella recovery was 〈 2. 7 MPN/g when the standard Salmonella addition was at the concentration of 0. 9 CFU/g when the mini-MSRV MPN method was employed. If the standard Salmonella addition were at 9. 0 and 90. 0 CFU/g, the recoveries of bacteria were 10. 1 and 94. 0 MPN/g, and the average recovery rate was 112% and 104% , respectively. Salmonella detection rate of modified mini-MSRV MPN,mini-MSRV MPN and regular MPN method was 18.4% （46/250）,5.2% （13/250） and 6. 0% （15/250） ,respectively. The detection rate was higher for modified mini-MSRV MPN method than of the other two methods （ X2 values were 19.68 and 17.82, respectively, all P values 〈 0. 05 ）. The detection quantity of Salmonella （ medians were 21.0, 〈 2.7 and 〈 3.0 MPN/g, respectively）. The quantity detected by modified mini-MSRV MPN method was higher than that of the other two methods （ both Z values were 5.71,both P values 〈 0.05 ）. Conclusion Modified mini-MSRV MPN method is an accurate method for foodborne Salmonella detection.