The discovery and characterisation of indigenous lactic acid bacteria (LAB) are important for diversity microbes as candidate probiotic. This research was aimed to identify lactic acid bacteria isolate from isolation process of local bovine rumen fluid from slaughterhouse in Surabaya Indonesia. Genotypic testing was conducted by analyzing 16S rDNA and biochemical identification. DNA of sample isolate was isolated and then amplified in vitro through the PCR method. Determination of nucleotide sequence of 16S rDNA was performed with sequencing method. The result of nucleotide sequence was than compared with GenBank database. The BLAST was then applied to identify the phylogenetic tree. Based on the biochemical characterization and nucleotide sequences, that isolate was identified as Lactobacillus rhamnosus subsp TG15. The result of this research showed that L.rhamnosus subsp TG15 showed viability bacteria in MRSA as control as much as 1.1 x 108 CFU/ml, mean while in MRSA pH 2, L.rhamnosus subsp TG15 showed its viability as much as 9.3 x 106 CFU/ml. Viability of isolate on bile tolerance 0.3% was 2.4 x 107 CFU/ml). Index antagonist bacteria test on S.aureus showed inhibition diameter as much as 2.0 mm and in antagonist test on E.coli as much as 2.5 mm. Based on the result, it could be concluded that this research found a new strain of lactic acid bacteria, L.rhamnosus subsp TG15 and that isolate has ability as the probiotic candidate. Keywords: L.rhamnosus subsp TG15; survival on acidity; bile salts; S.aureus and E.coli
Production of Lactic Acid and an Iodine Staining Substance by Bovine Rumen Bacteria