Preservative Efficacy of Bacteriocin Produced by Lactic Acid Bacteria Isolated from Fermented Green Gram Batter

The biological preservation of foods is considered to be safe and provide substantial health benefits to man a number of factors have been identified to contribute to the antimicrobial activity of lactic acid bacteria (LAB), which have attracted attention in recent years because of their generally regarded as safe (GRAS) status and efficacy as natural bio preservatives which can find applications in the food and cosmetic industries. The study aimed to evaluate the biopreservative properties of bacteriocins produced by lactic acid bacteria (LAB) isolated from fermented green gram batter. Using Man Rogosa and Sharpe (MRS) media, four distinct isolates (G1, G2, G3, and G4) were obtained. According to Bergey’s Manual of Systemic Bacteriology, isolates G1 and G2 were identified as Lactobacillus casei, while G3 and G4 were classified as Streptococcus species. The antimicrobial activity of bacteriocins from these isolates was tested at pH 5 and pH 7 using the well diffusion method, showing inhibitory effects against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Klebsiella species. Further research demonstrated the biopreservative effectiveness of bacteriocins G1, G2, G3, and G4 in both apple juice and coconut water. Notably, G1, G3, and G4 exhibited stronger antagonistic activity at pH 5, while G2 was more effective at pH 7. In apple juice, the Minimal Inhibitory Concentration (MIC) for Lactobacillus and Streptococcus was 25 l, whereas in coconut water, the MIC was 400 l.