Characterization of Bacteriocin Produced by Lactic Acid Bacteria Isolated from Solid Waste of Soymilk production

Biopreservation of food using bacteriocin from lactic acid bacteria (LAB) was an innovative breakthrough. Lactic acid bacteria can protect against food spoilage and pathogen bacteria by producing bacteriocin. The purpose of this study was to characterize the bacteriocin produced by LAB isolated from solid waste of soymilk that had probiotics properties. The LAB having antibacterial activities was evaluated their growth, and identified by using 16S rRNA gene sequence analysis. Its bacteriocin activities was tested on various pHs (2, 3, 4, 5, 6, 7, 8, and 9) and temperature (60-100 ° C). Its activities was evaluated againts pathogenic bacteria (Staphylococcus aureus ATCC 25923 and Listeria. monocytogenes CFSAN004330), enzymes (trypsin, catalase and protease-K), and antibiotics (penicillin and ampicillin). The results showed that LAB A23.4 isolates, which had 16S rRNA gene sequence were L. plantarum strain TMW 1.1623. Its Bacteriocin had antimicrobial activity against S. aureus ATCC 25923 and L. monocytogenes CFSAN004330 at pH 2-7, at temperatures of 60, 70, 80, 90, 100 ° C for 60 minutes and lysed by the enzymes trypsin and protease-K. Bacteriosin activity was stronger than that of the antibiotics of penicillin and ampicillin against S. aureus and L. monocytogenes. The inhibition zone of supernatant bacteriocin was 10 and 20 mm for S. aureus and L. monocytogenes. On the other hand, penicillin and ampicillin inhibition zones were 0 and 3 mm, respectively. From these results, it can be concluded that the antimicrobial produced by L. plantarum strain TMW 1.1623 was a bacteriocin used as food preservation that its processing using relatively wide range temperature (60-100) with pH 2-7.