广州市蔬菜类凉拌菜中微生物污染状况调查及大肠埃希氏菌耐药现象研究

Microbial contamination and antibiotic resistance analysis of Escherichia coli in vegetable cold dishes in Guangzhou

目的了解广州市蔬菜类凉拌菜的微生物污染状况及大肠埃希氏菌耐药情况。方法从广州市的超市、集贸摊点采集300份凉拌菜,依据GB 4789—2016进行微生物检验,用VETIK对检出的大肠埃希氏菌进行药敏实验, PCR法检测致泻性大肠埃希氏菌毒力基因。结果 300份样品中大肠菌群、大肠埃希氏菌、金黄色葡萄球菌和沙门氏菌的不合格率分别为40.0%、6.7%、1.3%和0.0%。药敏结果显示大肠埃希氏菌对头孢唑啉的抗性最高(40.0%)、其次为氨苄西林(30.0%),对其他受试抗生素不具有耐药性,且无多重耐药菌株。20株大肠埃希氏菌中检出3株致泻大肠埃希氏菌。结论广州地区蔬菜类凉拌菜中存在较为严重的微生物污染,食源性大肠埃希氏菌具有一定的耐药现象,应加大卫生监督力度,保障食品安全。

Objective To investigate the microbial contamination status and Escherichia coli antibiotic resistances in vegetable cold dishes in Guangzhou. Methods A total of 300 cold dishes were collected from supermarkets and trade stalls in Guangzhou, and microbial testing was carried out according to GB 4789—2016, drug-susceptivity testing was performed by VETIK of Escherichia coli, and the virulence genes of diarrhoeal Escherichia coli were examined by polymerase chain reaction(PCR). Results In 300 samples, the unqualified rates of coliform group, Escherichia coli, Staphylococcus aureus and Salmonella were 40.0%, 6.7%, 1.3% and 0.0%, respectively. The drug sensitivity results showed that Escherichia coli had the highest resistance to cefazolin(40.0%), followed by ampicillin(30.0%), and did not have resistance to other antibiotics, and there were no multidrug-resistant strains. Three strains of diarrhoeal Escherichia coli were detected in 20 strains of Escherichia coli. Conclusion There are serious microbial contaminations in the cold dishes in Guangzhou, and the foodborne Escherichia coli has certain drug resistance level, however, health supervision should be strengthened to ensure food safety.