Evaluating the antimicrobial effect of postbiotic extract from lactobacillus plantarum on Clostridium perfringens

Abstract

Abstract Background Humans have always sought to preserve food against spoilage through various factors such as pathogenic microbes. One of the methods is using naturally antimicrobial and antioxidant substances instead of chemical types. Probiotics can be noted among one of the sources of these substances. Among the limitations of using probiotics such as the growth and survival of bacteria are affected by external factors, transferring the antibiotic-resistant genes to intestinal pathogens; It can be considered to use potbiotics to inhibit pathogens or to treat diseases. Postbiotics provide a significant source of energy for colon epithelial cells, in addition to affecting several metabolic processes, they play a role in probotic microorganisms growth and differentiation and are helpful in optimizing intestinal health. Materials and Methods In this research, to evaluate the antimicrobial effect, the postbiotic extract was extracted from Lactobacillus plantarum (ATCC=14917) and was assessed against the pathogen Clostridium perfringens (ATCC=13124) by well diffusion and disk diffusion method and measuring the diameter of the non-growth halo. After that, the optimized concentration of the postbiotic extract (cell free supernatant and cell wall) was added to the food sample (chicken breast) containing Clostridium perfringens, and the total count o Clostridium perfringens and pH changes during days (1 and 5) were evaluated and was compared with the control sample of chicken breast. The desired experiments were performed in three repetitions. Results & Conclusion In evaluating the antimicrobial effect of postbiotic extract (cell free supernatant and cell wall) by well diffusion and disk diffusion method and measuring the diameter of the non-growth halo, the largest diameter was formed at a concentration of 200 µl/ml. Also, Clostridium perfringens decreased on days 1 and 5 in the evaluated chicken breast containing post-biotic (P ≤0.05). The pH of the chicken sample containing the postbiotic was 6.3-7-3 (P ≥ 0.05). These results showed the inhibitory effect of C. perfringens growth in chicken breast with postbiotic. Keywords: Supernatant, cell wall, lactobacillus plantarum, probiotic, postbiotic, Clostridium perfringens