Abstract: The effect of five strains of lactic acid bacteria (LAB) and Staphylococcus xylosus on the growth of Clostridium perfringens was investigated in this study. Mixed culture and conditioned culture were employed to evaluate the effects of these six strains on the growth, sporulation and spore germination of C. perfringens, and the antibacterial mechanism was also investigated. The results showed that Lactobacillus plantarum had the strongest inhibitory effect on C. perfringens growth and its spore germination and growth in both mixed culture and conditioned culture, and S. xylosus possessed the weakest inhibitory effect. None of the six strains could inhibit the sporulation of C. perfringens in the mixed culture, while in the conditioned culture, the sporulation of C. perfringens was inhibited by Lactobacillus fermentum, L. plantarum and Pentosaceus pentosaceus when pre-cultivated for 48 h. Besides, the low pH of the fermented broths of LAB and the heat-resistant bacteriocin produced by L. plantarum were crucial for inhibiting the proliferation of C. perfringens. This result showed that L. plantarum has the highest antibacterial capacity due to its ability to produce both acid and bacteriocin.

Key words: lactic acid bacteria, Staphylococcus xylosus, Clostridium perfringens, bacteriostatic mechanism, pH, bacteriocin