生猪肉加工厂食品接触面四环素耐药菌及其耐药基因的分布

Tetracycline-resistant Bacteria on Food Contact Surfaces in a Raw Pork Processing Plant and Distributions of Their Tetracycline Resistance Genes

摘要:

耐药菌的传播会对食品安全与人类健康造成严重威胁。本研究通过对某大型生猪肉加工厂食品接触面污染微生物四环素耐药情况进行分析，探讨其对生猪肉制品质量与安全的潜在危害。从生猪加工厂食品接触面共采集样品100份，共分离到168株细菌。通过药敏试验，发现60.7%的污染细菌对四环素具有耐药性，包括85.7%的假单胞菌属、85.7%的葡萄球菌属、86.7%的沙雷氏菌属、80%的乳球菌属、80%的大肠杆菌、60.0%的不动杆菌属和55.0%的气单胞菌属。通过对分离株进行15种四环素耐药基因的筛查，发现生猪肉加工厂设备食品接触面存在9种四环素耐药基因，包括tetL、tetA、tetB、tetC、tetE、tetM、tetS、tetK和tetX，其检出率分别为7.7%、6.0%、4.8%、4.8%、3.6%、3.6%、3.6%、1.2%和0.6%。本研究结果表明，生猪肉加工厂食品接触面四环素耐药菌污染严重，可能交叉污染生猪肉制品，其携带的四环素耐药基因可能向不同细菌种属间转移，进而由食物链向人类传播，对人类健康造成潜在的威胁。

Abstract:

The spread of drug-resistant bacteria poses a serious threat to food safety and human health. In this study, the tetracycline resistance of the contaminated microorganisms on the food-contact surfaces in a large raw pork processing plant was analyzed, and the potential quality and safety hazards in raw pork products. A total of 168 strains were isolated in the 100 samples collected .from the food contact surfaces in the plant. Drug sensitivity tests revealed that 60.7% of the contaminating bacteria were resistant to tetracycline, including Pseudomonas sp., 85.7%; Staphylococcus sp., 85.7%; Serratia sp., 86.7%; Lactococcus sp., 80%; Escherichia coli, 80%; Acinetobacter sp., 60.0%; Aeromonas sp., 55.0%. Through screening 15 tetracycline resistance genes in the isolated strains, nine tetracycline resistance genes with different detection rates were found (including tetL, 7.7%; tetA, 6.0%; tetB, 4.8%; tetC, 4.8%; tetE, 3.6%; tetM, 3.6%; tetS, 3.6%; tetK, 1.2%; tetX, 0.6%). These results indicated the high prevalence and cross contamination of tetracycline-resistant bacteria on food-contact surfaces in the plant and in raw pork products, and the possible spread of tetracycline resistance genes among different bacterial species and along the food chain to humans, which will pose a potential threat to human health.