Study on biofilm formation of foodborne Listeria monocytogenes serotype 1/2c strains

Objective To compare the biofilm formation of Listeria monocytogenes serotype 1/2c strains and other serotypes strains under different conditions. Methods By using microplate assay with crystal violet staining, the biofilm formations of L. monocytogenes serotype 1/2c and other serotypes strains under different temperatures, culture mediums and pH conditions were detected. Results L. monocytogenes serotype 1/2c strains formed more biofilm compared with other serotypes strains at 25 ℃ (P0.05). In TSB medium and 10% TSB medium, serotype 1/2c strains showed stronger biofilm formation than other serotype strains (P0.05), and under the condition of pH 7 and pH 8, L. monocytogenes serotype 1/2c strains formed more biofilm than other serotypes strains in culture medium (P0.05). Conclusion Biofilm formation capability of L. monocytogenes serotype 1/2c strains is stronger than that of other serotype L. monocytogenes strains at room temperature, in rich and poor medium and under neutral and alkalescent condition, suggesting the possible reason for high detection rate of L. monocytogenes serotype 1/2c strains in raw meat and food.