Full Length Research Paper

Lack of correlation between H₂O₂ production and in vitro anti-staphyloccocal activity of vaginal Lactobacillus spp.

Hyun-Su Jung¹, Jeong-Min Jeon² and Jae-Seong So^{1, 2}*

¹Department of Biological Engineering and Center for Advanced Bioseparation Technique, Inha University, Incheon, 402-751, South Korea.

²Graduate Program of Marine Science and Biotechnology, Inha University, Incheon 402-751, South Korea.

*Corresponding author. E-mail: sjaeseon@inha.ac.kr. Phone: + 82-32-860-7516; Fax: +82-32-875-0827.

Accepted 11 December, 2008

Lactobacilli are considered to play important roles in human health as they are known to secrete inhibitory substances to prevent infection by pathogenic organisms. Previously we have isolated 77 strains of Lactobacillus spp. from human vaginas. In this study, using the plate diffusion method, strains showing in vitro antagonistic activity against pathogenic Staphylococcus aureus were screened. Because Lactobacillus spp. are known to produce hydrogen peroxide (H₂O₂) as an antimicrobial substance, we attempted to determine if there is a consistent link between in vitro anti-staphylococcal activity and H₂O₂ production by Lactobacillus spp. A simple quantitative analysis of H₂O₂ produced by Lactobacillus spp. was performed by a modified spectrophotometric method. A statistically significant correlation was not found between in vitro anti-staphylococcal activity and H₂O₂ production.

Key words: Lactobacillus spp., vaginal Lactobacillus spp., anti-staphylococcal activity, H₂O₂ production.