Antimicrobial properties of lactic acid bacteria from fermented palm sap against E. coli and S. aureus growth

Abstract

Palm sap produced from tapping can be a growing place for lactic acid bacteria (LAB). Palm sap has a lot of carbohydrate content, such as sucrose, fructose, and glucose, which can be a source of nutrition for the growth of microorganisms such as LAB). The result of LAB metabolism that is formed can be in the form of organic acid acids that can act as antimicrobial compounds. LAB have been isolated from fermented palm sap. This study aimed to determine the antibacterial properties of LAB from the fermentation of palm sap against E. coli and S. aureus using the well-agar diffusion method and the paper disc diffusion method. The study showed that LAB isolates (Lactobacillus A1, A6, B12, C1, and C4) and cell-free supernatants have antibacterial activity against E. coli and S. aureus. LAB antibacterial properties using cells with a clear zone diameter against E. coli ranges from 8.03 to 0.58 mm, and S. aureus inhibition zone diameter ranges from 9.13 to 11.16 mm. The antimicrobial activity of LAB using cell-free supernatants against E. coli ranges from 4.59 to 5.01 mm, and the diameter of the inhibitory zone against S. aureus ranges from 4.34 to 5.79 mm. From these results, LAB isolated from fermented palm sap can potentially be probiotics.