3种柑橘类精油对食源性致病菌的抑菌活性及协同增效作用OA

Using Escherichia coli,Shigella spp.and Staphylococcus aureus as indicator bacteria,the anti-bacterial activities of three citrus essential oils were evaluated and the combinations with synergistic effects were screened.The Kirby-Bauer disc diffusion assay showed that bergamot,yellow lemon,and green lemon es-sential oils formed inhibition zones(10.09-26.38 mm),with minimum inhibitory concentration(MIC)of 3.75-15 mL/L and minimum bactericidal concentration(MBC)of 7.5-60 mL/L,respectively.Bergamot essential oil exhibited antibacterial activity against all three tested bacterial strains with the lowest MIC values(3.75 mL/L for each),indicating the strongest and broad-spectrum antibacterial effect.Checkerboard dilution tests revealed a synergistic effect(FICI=0.5)at a volume ratio of 1∶1(V/V)yellow lemon and bergamot essential oil combination against E.coli,reducing the MIC from 3.75 mL/L to 0.9375 mL/L.While,it exhibited FICI values of 0.75 against S.aureus and 1.25 against Shigella spp.,indicating additive and indifferent effect respectively.In a chilled chicken breast model at 0-4℃,the total bacterial count on day 7 of the combined es-sential oil-activated carbon sustained-release treatment was 3.955 lg CFU/g,which was significantly lower than that of the control group(4.956 lg CFU/g,P<0.05),and extended the period during which the total viable count remained≤5 lg CFU/g from 7 to 10 days.