PARICHAT PHUMKHACHORN AND PONGSAK RATTANACHAIKUNSOPON
Department of Biological Science, Faculty of Science, Ubon Ratchathani University, Warin Chamrap, Ubon
Ratchathani-34190, Thailand
*(e-mail : rattanachaikunsopon@yahoo.com; Contact : +66- 0867792834)
(Received : February 20, 2022; Accepted : March 18, 2022)
ABSTRACT
Probiotic microorganisms are live microorganisms, when administered in adequate amounts, confer a
health benefit. Most probiotic microorganisms generally belong to lactic acid bacteria. Therefore, this
study was aimed at finding lactic acid bacteria (LAB) having probiotic properties. Twelve isolates of LAB
isolated from four different Thai traditional fermented foods including Nham (fermented pork rind),
PlaSom (fermented fish), Kung Jom (fermented shrimp paste) and Mum (fermented ground beef) were
tested for their tolerance to acid and to bile salt, considering with important probiotic properties. It was
found that LAB isolate M2, isolated from Mum, was the most tolerant isolate to acid at pH 2 and to bile
salt at the concentration of 2%. Furthermore, the study showed that LAB isolate M2 had antimicrobial
ability against Escherichia coli O157 : H7 ATCC 43895 and Staphylococcus aureus ATCC 25923. Based on
16S rDNA sequence analysis and phylogenetic tree analysis, the LAB isolate M2 was found to be closely
related to Lactobacillus gasseri strain ATCC 33323 (accession number NR_075051.2). The LAB isolate
with probiotic properties obtained from this study can be further characterized in order to utilize it in
the future.
Key words : Fermented foods, lactic acid bacteria, Lactobacillus gasseri, probiotics