Abstract:Objective To elucidate the antibiotic-resistance(AR) distribution,AR level and the transfer of AR genes in non-pathogens isolated from ready-to-eat food in Xi’an,and evaluate the potential food safety risk.Methods The erythromycin and ampicillin resistance,the AR gene transfer,16S rRNA gene sequence analysis were performed on the bacteria from ready-to-eat food samples collected from supermarkets of Xi’an,including cooked meat,fruit slices and Chinese salads.Results 42.5% of the isolates were erythromycin resistant,47.5% were ampicillin resistant,while 21.2% were resistant to both antibiotics.11.3% of Ermr strains could grow under 160mg/L Ermthromycin,6.3% of Ampr strains could grow under 500mg/L ampicillin.After 1000 generations on medium without antibiotic,60% and 45% of randomly selected Ampr and Ermr strains lost their antibiotic resistance.Within these strains,the Ermr and Ampr fragments could be transferred from the antibiotic-resistant strains into the negative strains.Most antibiotic-resistant strains belonged to Enterococcus,Staphylococcus,Bacillus and Pseudomonas.Conclusion There was a potential food safety risk of non-pathogens in ready-to-eat food,and the transfer of AR genes might have some impact on the human intestinal flora and pathogenic bacteria.