食品中3种克罗诺杆菌标准检测方法的比对研究

Comparative study on 3 kinds of standard detection methods of Cronobacter in food

中文关键词:  克罗诺杆菌  GB 4789.40  ISO 22964  方法比对  耐药性

英文关键词:Cronobacter  GB 4789.40  ISO 22964  comparison of method  antibiotic susceptibility

中文摘要:

      目的 比较3种国内外克罗诺杆菌检测方法, 验证GB 4789.40—2016《食品安全国家标准 食品微生物学检验 克罗诺杆菌属(阪崎肠杆菌)检验》、GB 4789.40—2024《食品安全国家标准 食品微生物学检验 克罗诺杆菌检验》和ISO 22964—2017《食物链微生物学—克罗诺杆菌的水平检测方法》3种标准方法的实际检测性能。方法 采用3种标准方法, 对2020—2022年采集的包括婴儿配方奶粉、谷基婴幼儿辅食、玉米原料和婴儿配方奶粉原辅料在内的403份样品进行克罗诺杆菌的检测, 并对克罗诺杆菌分离株进行药物敏感性检测。结果 403份样品中克罗诺杆菌的总污染率为17.9% (72/403), 玉米原料、谷基婴幼儿辅食和婴儿配方奶粉的污染率分别为37.3% (38/102)、23.4% (33/141)和1.0% (1/100)。3种标准方法的总检出率虽然没有显著差异(2=3.601, P=0.170), 但41.5 ℃相较于44 ℃可以有效提升检出率(2=18.813, P=0.000)。72株克罗诺杆菌耐药率为55.6% (40/72), 其中头孢唑林、氨苄西林、阿莫西林/克拉维酸耐药率分别为52.8% (38/72)、5.6% (4/72)、1.4% (1/72)。结论 本研究表明GB 4789.40—2024已达到国际相关方法的水平, 为GB 4789.40和ISO 22964方法检测结果的互认提供数据支持。克罗诺杆菌对头孢唑林具有较高的耐药性, 在临床治疗选择抗生素时应避免使用该药物。

英文摘要:

      Objective To compare three domestic and foreign Cronobacter detection methods, for verifying the actual detection performance of three standard methods: GB 4789.40—2016 National standard for food safety food-Microbiology tests Cronobacter spp. (Enterobacter sakazakii) test, GB 4789.40—2024 National standard for food safety food-Microbiology tests Cronobacter test and ISO 22964—2017 Food chain microbiology-Horizontal detection methods for Cronobacter spp. Methods Three standard methods were used to detect Cronobacter in 403 samples collected from 2020 to 2022, including infant formula, cereal-based infant supplements, corn ingredients, and raw and supplemental ingredients of infant formula, and to test Cronobacter isolates for drug susceptibility. Results The total contamination rate of Cronobacter in 403 samples was 17.9% (72/403), and the contamination rates of corn raw material, cereal-based infant supplement and infant formula were 37.3% (38/102), 23.4% (33/141) and 1.0% (1/100), respectively. Although there was no significant difference in the total detection rate among the three standard methods (2=3.601, P=0.170), 41.5 ℃ could effectively improve the detection rate compared with 44 ℃ (2=18.813, P=0.000). The resistance rate of 72 strains of Cronobacter was 55.6% (40/72), among which the resistance rates of cefazolin, ampicillin, and amoxicillin/clavulanic acid were 52.8% (38/72), 5.6% (4/72), and 1.4% (1/72), respectively. Conclusion This study shows that GB 4789.40—2024 has reached the level of the international relevant methods, providing data support for the mutual recognition of the test results of GB 4789.40 and ISO 22964 methods. Cronobacter has high resistance to cefazolin, which should be avoided when choosing antibiotics for clinical treatment.