In vitro antimicrobial activities of metabolites from vaginal Lactobacillus strains against Clostridium perfringens isolated from a woman's vagina.

BACKGROUND More than 50 different species of bacteria may live in a woman's vagina, with lactobacilli being the predominant microorganism found in healthy adult females. Lactobacilli are relevant as a barrier to infection and are important in the impairment of colonization by pathogens, owing to competitive adherence to adhesion sites in the vaginal epithelium and their capacity to produce antimicrobial compounds. METHODS The aim of the present study was to demonstrate the inhibitory capability of Lactobacillus metabolites against Clostridium perfringens, an anaerobic Gram-positive bacterium. These bacteria were isolated from vaginal swabs by using culture-dependent approaches, and the bacteriostatic effect of Lactobacillus metabolites, extracted from different isolates, was assessed using a modified E test. RESULTS Among the 100 vaginal swabs, 59 (59%) samples showed the presence of Lactobacillus strains and only one sample contained C. perfringens. Lactobacillus metabolites demonstrated the significant potency of in vitro activity against C. perfringens, with minimal inhibitory concentration values ranging from 15.6 μg/mL to 31.2 μg/mL. CONCLUSION This study suggests that women without vaginal Lactobacillus strains may be susceptible to nonindigenous and potentially harmful microorganisms.