Evaluation of probiotic and anti-inflammatory properties of bacteriocinogenic Pediococcus acidilactici HW01 and Leuconostoc citreum HW02 from malted barley

Background: Bacteriocins are peptides with antibacterial properties that are released by lactic acid bacteria and affect genetically closely related bacteria. Settled bacteriocin-producing probiotics in the GI tract may contribute to bacteriocin formation, which can lead to pathogen inhibition and immune system regulation. The purpose of this study is to evaluate the probiotic capabilities of bacteriocin-producing LAB isolated from malted barley, Pediococcus acidilactici HW01, and Leuconostoc citreum HW02. Results: Both strains could survive in harsh GI conditions such as low pH, bile salt, pepsin, and lysozyme. Furthermore, exhibited non-haemolytic activity and tetracycline and erythromycin susceptibilities. In vitro adhesion of HW01 and HW02 strains to HT-29 cells was 76.28 and 75.99%, respectively. Auto-aggregation ability of HW01 and HW02 was about 14%, but their ability to aggregate with pathogens (Escherichia coli, Salmonella enterica ser. Typhimurium, Staphylococcus aureus and Listeria monocytogenes) ranged from 32.0% to 43.5%. Regarding the anti-inflammatory effect, heat-killed bacteriocin-producing strains suppressed the mRNA expression levels of cytokines and chemokines in RAW 264.7 macrophages induced by LPS (P < 0.005). Conclusions: Bacteriocin-producing P. acidilactici HW01 and Leu. citreum HW02 may be good probiotic candidates. Graphical Abstract: [Figure not available: see fulltext.]