Bacteriocin-producing lactic Acid bacteria isolated from traditional fermented food

Area of Science:

• Microbiology
• Food Science
• Biochemistry

Background:

• Lactic Acid Bacteria (LAB) are crucial in fermenting foods like tempeh, tempoyak, and tapai.
• Bacteriocins produced by LAB show potential as natural food preservatives.
• Screening LAB from traditional fermented foods can identify novel bacteriocin producers.

Purpose of the Study:

• To screen Lactic Acid Bacteria (LAB) from traditional fermented foods for bacteriocin production.
• To identify and characterize a bacteriocin-producing strain and its antimicrobial substance.
• To determine the optimal conditions for bacteriocin production and its sensitivity to enzymes.

Main Methods:

• Isolation and screening of LAB from tempeh, tempoyak, and tapai.
• Identification of inhibitory strains using standard microbiological techniques.
• Characterization of the inhibitory substance through enzyme sensitivity assays and determination of production kinetics.

Main Results:

• One strain from tempeh, identified as Lactobacillus plantarum BS2, exhibited inhibitory activity against other LAB.
• The inhibitory activity was confirmed to be bacteriocin-mediated, not due to hydrogen peroxide, organic acids, or bacteriophages.
• Maximum bacteriocin production reached 200 AU/ml after 10 hours of incubation.
• The bacteriocin demonstrated sensitivity to proteases (trypsin, α-chymotrypsin, β-chymotrypsin), α-amylase, and lysozyme.

Conclusions:

• Lactobacillus plantarum BS2 isolated from tempeh is a promising bacteriocin producer.
• The identified bacteriocin has potential applications as a natural antimicrobial agent in food preservation.
• Further research into the purification and structure of this bacteriocin is warranted.