Antibacterial effect of soaps made from some milk products

Keywords: Fermented milk products, Soap, Antibacterial activity The expectation of more environmentally friendly soap production using natural products is a promising alternative to synthetic chemicals used in soaps. Recently, the evaluation of antioxidant and antimicrobial-rich biomass waste for soap formulation has attracted the interest of researchers. In this study, it was aimed to determine the antibacterial activity of solid soaps produced using various milk productins (kefir, whey, yoghurt) on Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922 and Staphylococcus epidermidis ATCC 12228 bacteria. Kefir, whey and yoghurt water soaps produced from olive oil were dissolved with sterile water at the desired concentration (100, 250 and 500 mg/mL) after waiting for 3 months. The aqueous soap solution in the concentration obtained was made ready for antibacterial activity by absorbing 20 µL on sterile discs. Disc diffusion method was used to determine the antibacterial activity. A commercially available antibacterial soap and Gentamicin antibiotic were used as a positive control, and a non-fermented milk-free soap was used in the experiment as a negative control. In the experimental results, it was determined that the positive control had an antibacterial effect on the test microorganisms at all concentrations. Soap produced from whey at 500 mg/mL concentration on E. coli bacteria formed an inhibition zone diameter of 10 mm, yoghurt water 10 mm, and kefir 12 mm. It was determined that soaps obtained from fermented milk products were effective on E. coli at a concentration of 500 mg/mL, but had low activity at other concentrations. The higher activity of kefir soap compared to other soaps suggested that it may be due to the beneficial microorganisms it contains and the metabolites they produce. It was observed that soaps produced on S. aureus and S. epidermidis did not have antibacterial activity