Antimicrobial Potential of Limosilactobacillus Fermentum Isolated from Bilih Fish (Mystacoleucus padangensis) of Singkarak Lake, West Sumatera, Indonesia

Background and Objective: Lactic acid bacteria have recently become one of the major topics of discussion in fields of health, food industry, science, animal husbandry and agriculture. Lactic acid bacteria have been widely used in fermentation of various types of food products from animals, fish and plants that act as preservatives and include positive effects on human health and beauty. One source of lactic acid bacteria is Mystacoleucus padangensis fish from Singkarak Lake, West Sumatera, Indonesia, where a probiotic bacterium of Limosilactobacillus fermentum with antimicrobial potential is isolated. The aim of this study was to assess antimicrobial potential of Limosilactobacillus fermentum isolated from Bilih fish from Singkarak Lake, Indonesia. Material and Methods: Methods of this study were as follows: isolation of lactic acid bacteria from Bilih fish from Singkarak Lake, followed by antimicrobial activity assessment of the raw bacteriocin supernatant. Then, 16S rRNA was used to assess species of the lactic acid bacteria isolates. From the three samples, one sample of Isolate IB1, with potential antimicrobial activity was reported. Results and Conclusion: Results of the study showed that the morphological and biochemical characteristics of lactic acid bacteria included Gram-positive, bacilli form and catalase-negative belonged to the group of homofermentative bacteria. The greatest antimicrobial activities were shown by IB1 Escherichia coli 0157:H7 (27.29 mm), Staphylococcus aureus ATCC 25923 (14.17 mm) and Listeria momocytogenes CFSAN 004330 (11.44 mm) while the diameter of inhibition zone by the supernatant of Lactic acid bacteria Escherichia coli 0157:H7 crude bacteriocin was 16.89 mm while Staphylococcus aureus ATCC 25923 did not form inhibition zone. The observed antimicrobial activity was 17.19 mm for Listeria monocytogenes CFSAN 004330 at neutral pH. Results of the molecular identification using 16S rRNA showed that the isolated lactic acid bacteria included similarities with Limucilactbacillus fermentum strain 17059 16S, which included antimicrobial potentials against pathogenic bacteria. Limosilactobacillus fermentum 17059 16S can be used as an antidiarrheal and antityphoid agent in humans and as a natural preservative in foods. Conflict of interest: The authors declare no conflict of interest