Optimization, Partial Purification, and Characterization of Bioactive Peptides of Lactobacillus paracasei Isolated from Traditional Egyptian Cheese

Background: Bacteriocins are small peptides which are ribosomally synthesized and have been shown to have wide range of antimicrobial activity. The aim of this study was to optimize the production of L. paracasei MG۸۴۷۵۸۹ bacteriocin. Furthermore, the potential antibacterial properties of the novel bacteriocins were characterized and evaluated against Staphylococcus aureus. Methods: The present study optimized the growth media constituents of Lactobacillus paracasei MG۸۴۷۵۸۹ to improve bacteriocin yield by applying One-Factor-at-a-Time (OFAT) and Response Surface Methodology (RSM) methods. Results: At OFAT, two-fold activity increased against Staphylococcus aureus in the presence of whey (۲۲.۵ g/L) as nitrogen source and sucrose (۳۰ g/L) as carbon source. RSM tool was performed with media compounds using design expert ۱۲.۰.۱.۰. Whey (۲۲.۵ g/L), sucrose (۳۰ g/L), temperature (۳۰ ºC), and pH (۶.۵) condition yielded ۲۵,۶۰۰ AU/ml of bacteriocin against S. aureus. Bacteriocin was stable at pH range of ۲.۰ to ۸.۰ for one h and at ۶۰ ºC for ۱۵ min. The produced antimicrobial peptide is a novel bacteriocin with molecular mass of ۲,۶۱۱.۱۲۲ Da. Conclusion: Bacteriocin of L. paracasei MG۸۴۷۵۸۹ isolated from traditional Egyptian cheese (Kareish) showed great antimicrobial activity and could be applied as food preservative in food manufacturing. DOI: ۱۰.۱۸۵۰۲/jfqhc.۹.۴.۱۱۳۷۵

Keywords:

Bacteriocins , Peptides , Lactobacillales , Lacticaseibacillus paracasei , Anti-Bacterial Agents , Staphylococcus aureus