Abstract: The sensitivity of Bacillus licheniformis to different preservatives was tested by disk diffusion method and minimum inhibitory concentration (MIC) assay. The optimal combination of preservatives against Bacillus licheniformis was determined using orthogonal array design method and validated. The results showed that Bacillus licheniformis was not sensitive to natamycin, sorbic acid, potassium and sodium lactate, but sensitive to nisin, ε-polylysine and ethylparaben, revealing an inhibition zone diameter of 9.25, 10 mm and 7.25 mm and an MIC of 0.078, 0.078 mg/mL and 2.5 mg/mL, respectively. The combination of nisin, ε-polylysine and ethylparaben at respective concentrations of 0.313, 0.313 mg/mL and 0.125 mg/mL showed the best inhibitory effect on Bacillus licheniformis with a 2(lg(CFU/g)) decrease 5.48(lg(CFU/g)) for the blank sample. Furthermore, the preservative combination indicated better inhibitory effect on Bacillus licheniformis in meat products, dairy products and juice during storage at 0－4 ℃.

Key words: preservatives, Bacillus licheniormis, total plate count