Effectivity of Plantaricin from Indonesian LactobacilhlS plantarum As Antimicrobial Substances against Escherichia coli

Abstract

Indonesian indigenous strains of Lactobacillus plantarum IIA-IAS was isolated from Indonesian local beef: and identified by 16S rRNA sequencing. L.pltmtarum IIA-lAS are able to produce plantaricin, tenned plantaricin llA-IAS. The aim of this research was to evaluate effectivity ofplantaricin IIA-lAS as antimicobial substances against Escherichia coli. Parameters analyzed were the effect of the presence of lipoteichoic acid (LTA) on plantaricin IIA-lAS adsorption, analysis ofN-acetyl-glucosamine, bacterial cell leakage, and changes in bacterial cell morphology by scanning electron microscope. The result showed that LTA significantly improve the absorption ofplantaricin to cell wall of E. coli 3-fold higher than in the absence of LT A. It is acceptable that the addition of LTA might facilitate the binding of plantaricin to the bacterium. Plantaricin IIA-lAS could disrupt the N-acetyl-gucosamine (NAG) on peptidoglican of cell wall of E.coli. Microscopic morphology by Scanning Electron Microscope of E.coli treated with plantaricin llA-lAS was remarkably different compared to that of the untreated cells. This is hypothesiz.ed may be due to ability ofplantaricin IIA-lAS to disrupt cell membrane and promote cell leakage of E.coli.