Lactic Acid Bacterium With Antimicrobial Properties From Selected Malay Traditional Fermented Foods

Abstract

Traditional or local fermented foods have been the favourite sources for Lactic acid bacteria (LAB) used for starter cultures. Traditional food such as fermented cassava ‘tapai ubi’, fermented glutinous rice ‘tapai pulut’ and fermented shrimp paste ‘belacan’ have been local heritage consumed as Malay delicacies. In this work, 33 LAB samples were isolated from tapai ubi, tapai pulut and belacan and out of these only 5 LAB isolates (PG, PH, BG, UG and UL) showed inhibitory properties against selected indicator organisms (Bacillus subtilis, Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus). Morphologically, isolate PG, PH, BG are cocci, UL is rod and UG is coccobacillus. Biochemically, isolates (PG, PH, BG UL and UG) are found to be Gram positive, non motile, lactose fermenter and catalase negative. The 16s Ribosomal RNA gene sequencing was carried out and each was identified with an accession number (PB: MT645488, PH: MT645489; BG: MT645490 UG: MT645491 and UL MT645492). Isolates PG and PH from tapai pulut belonged to Pediococcus pentosaceus (at 99% and 98%, respectively). Meanwhile, isolate from Belacan BG belonged to Enterococcus faecium (99%), and those from fermented shrimp, UG and UL belonged to Weissella confusa (99%), and Lactobacillus fermentum (98%), respectively. Majority of the isolates demonstrated broad spectrum inhibition against both Gram positive and negative indicator strains. Compared to the rest of isolates, PH exhibited the highest antibacterial activity against Bacillus subtilis. These results suggested that isolate PH are the most potent isolates which is producing antimicrobial agent with potential as food preservatives.