Microbiological, Biochemical, and Antibiotic susceptibility analysis of the lactic acid bacterial culture Lactobacillus acidophilus (MTCC No: 10307)

Abstract

The association between health and food has led to an increased interest in functional foods, which are enriched with physiologically active components that provide additional benefits beyond basic nutrition. Probiotics, a subset of functional foods, are live microorganisms that confer health benefits when consumed in adequate amounts. This study aimed to assess the antibiotic susceptibility pattern of Lactobacillus acidophilus, a commonly used probiotic culture, as well as compare it with reference probiotics and food-borne pathogens. The purity of the probiotic culture was tested through various microbiological tests. The antibiotic susceptibility test was performed using the standard disc diffusion assay on the modified Kirby-Bauer method. A total of 36 antibiotics were tested, and the results were interpreted based on established guidelines. Statistical analysis was conducted using One-way ANOVA. The results indicated that intrinsic resistance was observed in some antibiotic families however, this intrinsic resistance is usually non-transferable and possesses no risk. The findings of this study will contribute to understanding the safety and potential antibiotic resistance of probiotic cultures used in food products.