Efficacy of lactic acid and acetic acid against multidrug resistant Staphylococcus aureus, E. coli and klebsiella sp.

Abstract

In the phase of emerging antibiotic resistance, the efficacy of organic acids including lactic acid and acetic acid proved worth applicable. The rational use of antibiotics has always been challenging. The overuse and under-use of antimicrobials provokes the development of resistance, through which multidrug Resistant (MDR) strains have emerged. In this experiment we trialed MDR strains of Staphylococcus aureus, Escherichia. coli and Klebsiella sp. recovered from clinical cases of mastitis through broth dilution method followed by disc diffusion technique to demonstrate the minimum inhibitory concentration (MIC) and minimum bacteriocidal concentration (MBC) for lactic and acetic acids. For lactic acid the MIC for Staphylococcus aureus, E. coli and Klebsiella sp. was 0.78µl, 0.39µl and 0.39µl respectively at the 0.5 McFarland turbidity standard. The zone of inhibition (ZOI) was ranging from 18mm±1 to 20mm±1 in diameter. However, the acetic acid MIC of 0.78µl was found equally effective against all test bacterial spp. with ZOI of 18mm±1 to 19mm±1 in diameter. Moreover, the MBC for lactic acid was 1.56ul against Staphylococcus, 0.78ul for E. coli and Klebsiella spp. exhibiting the ZOI ranging from 20mm±1 to 22mm ±1 in diameter. Acetic acid revealed the MBC of 1.56ul against all test bacterial spp. having ZOI ranging from 19mm±1 to 22mm±1 in diameter.