Broad‐spectrum antimicrobial activity of cinnamoyl esterase‐producing Lactobacilli and their application in fermented rice bran

• Published in: Journal of the science of food and agriculture Vol. 102; no. 8; pp. 3130 - 3139
• Main Authors: Kim, Jong‐Hui, Lee, Eun‐Seon, Kim, Bu‐Min, Ham, Jun‐Sang, Oh, Mi‐Hwa
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.06.2022; John Wiley and Sons, Limited
• Subjects: Acids; agriculture; Anti-Bacterial Agents - pharmacology; Anti-Infective Agents; Antibacterial activity; antibacterial properties; Antimicrobial activity; Antioxidants; Aspergillus niger; Bacillus cereus; Bacteria; bile salts; Bioactive compounds; Biological activity; Caffeic acid; Chemical compounds; cinnamoyl esterase; E coli; Escherichia coli; Escherichia coli O157; Esterase; Esterases; feces; Fermentation; Fermented food; Fermented Foods - microbiology; Ferulic acid; Food industry; fungal growth; Fungi; Fusarium oxysporum; Lactic acid; Lactic acid bacteria; Lactobacilli; Lactobacillus fermentum; Lactobacillus gasseri; Limosilactobacillus fermentum; Listeria monocytogenes; Metabolites; Oryza - microbiology; Pathogens; Penicillium; Phenolic acids; Phenols; Rice; Rice bran; rice bran fermentation; Salmonella enterica; Shelf life; Staphylococcus aureus; Strains (organisms); Survival; survival rate; Toxins; cinnamoyl esterase; antimicrobial activity; Lactobacilli; rice bran fermentation
• ISSN: 0022-5142; 1097-0010; 1097-0010
• DOI: 10.1002/jsfa.11654

BACKGROUND Cinnamoyl esterase (CE) can release antioxidant phenolic acids from its non‐digestible ester‐linked form. Fermentation using CE‐producing lactic acid bacteria (LAB) can be useful in the food industry because of its ability to produce bioactive compounds and antibacterial metabolites. The purpose of this study was to confirm the food applicability of LAB with CE‐producing ability and broad‐spectrum antibacterial activity. RESULTS Among the 219 bacterial strains identified in infant feces, five Lactobacillus gasseri and six Limosilactobacillus fermentum with a high CE activity were isolated. The survival rate of all selected LABs was > 95% at pH 2.5 for 3 h and > 70% when treated with 0.3% bile salt for 4 h. Moreover, cell‐free supernatants of all strains strongly inhibited five food‐borne bacterial pathogens (Listeria monocytogenes, Salmonella enterica, Escherichia coli O157:H7, Bacillus cereus, and Staphylococcus aureus) and three toxin‐producing fungal pathogens (Aspergillus niger, Penicillium sp., and Fusarium oxysporum). To improve phenolic acid content and rice bran preservation, Limosilactobacillus fermentum J2 with the strongest CE activity and Lactobacillus gasseri N2 with the strongest antibacterial activity were used in rice bran fermentation, respectively. FRB‐J2 (fermented rice bran with Limosilactobacillus fermentum J2) and FRB‐N2 (fermented rice bran with Lactobacillus gasseri N2) significantly increased caffeic acid and ferulic acid (P < 0.01). FRB‐J2 and FRB‐N2 artificially inoculated with F. oxysporum showed no visible fungal growth during the test period (21 days). CONCLUSION Fermentation by Limosilactobacillus fermentum J2 and Lactobacillus gasseri N2 can help extend the shelf life of rice bran‐based products and produce bioactive compounds. © 2021 Society of Chemical Industry.