Asian Journal of Microbiology, Biotechnology & Environmental Sciences Paper

Vol 22, Issue 3, 2020; Page No.(504-508)

PRELIMINARY STUDY ON CHARACTERIZATION OF BACTERIOCIN-LIKE INHIBITING SUBSTANCES (BLIS) FROM ISOLATED ORAL BACTERIA

CHARITY SUME GONDWE, SHAMALA MARIMUTHU AND SRI MAHA SATYADEWI SUPRAMANIAM

Abstract

Oral cavity contains a wide range of bacteria species with dominant micro flora Streptococcus, other genus includes Lactobacillus, Enterococcus and Staphylococcus. The present study was aimed to isolate and identify oral bacteria using biochemical and molecular analysis respectively and to characterize oral bacteria for production of bacteriocin like inhibiting substances (BLIS). Oral samples were cultured on selective Mitis Salivarius Agar (MSA) plates and the colonies were isolated. The isolated strains were identified using biochemical tests including gram staining, catalase test, hemolysis and urease test where all the isolated strains were gram positive, catalase negative, urease negative and showed alpha hemolysis activity. The morphological and biochemical characterization confirmed that the isolated bacteria was from genus Streptococcus. It was further confirmed by molecular analysis where genomic DNA was isolated and verified qualitatively by nanodrop and quantitatively by gel electrophoresis. The concentration was within the range of 4.2 μg/mL – 17.6 μg/mL and purity 1.77-2.65. 16SrRNA gene was amplified and sequenced, three samples showed positive results where A1 was Streptococcus salivarius B0023-01R, A2 was Streptococcus salivarius YL456 and B1 was Streptococcus salivarius SAM3 with relatively 99% reference to query sequence using NCBI BLASTn. Streptococcus salivarius was also able to produce bacteriocin-like inhibiting substances (BLIS) which inhibited growth of Staphylococcus aureus.