Novel Potential Probiotic Lactobacilli for Prevention and Treatment of Vulvovaginal Infections

Lactobacilli in the vaginal tract are essential to protect against microbial infections. We therefore focused on isolating vaginal lactobacilli from pregnant women and testing their functional properties. Lactobacilli were isolated from 50 vaginal swabs and the purified isolates were identified by MALDI-TOF MS. Functional properties (antimicrobial activity, organic acids and hydrogen peroxide production, antibiotic susceptibility, auto-aggregation, and hydrophobicity) of selected isolates were tested. Lactobacilli (41 strains) were identified in 58% of swabs with a predominance ofLactobacillus crispatus(48%) followed byL. jensenii(21%),L. rhamnosus(14%),L. fermentum(10%), andL. gasseri(7%). The highest antibacterial activity was determined forL. fermentumandL. rhamnosus. Strong anti-Candidaactivity was observed for strainsL. crispatus,L. fermentum, andL. rhamnosus. StrainL. jensenii58C possessed the highest production of hydrogen peroxide (6.32 +/- 0.60 mg/l). The best lactic acid producer was strainL. rhamnosus72A (11.6 +/- 0.2 g/l). All strains were resistant to fluconazole and metronidazole. The highest auto-aggregation was observed for strainL. crispatus51A (98.8 +/- 0.1% after 24 h). StrainL. rhamnosus68A showed the highest hydrophobicity (69.1 +/- 1.4%). StrainsL. fermentumandL. rhamnosusshowed high antibacterial activity and hydrophobicity, and strainsL. crispatuspossessed high auto-aggregation and anti-Candidaactivity. Thus, these strains alone or in a mix could be used for the preparation of probiotic products for treatment and prevention of vulvovaginal infections of pregnant and non-pregnant women.

Automated summary

This study focused on isolating vaginal lactobacilli from pregnant women and testing their functional properties. The results showed that L. fermentum and L. rhamnosus exhibited high antibacterial activity, while L. crispatus, L. fermentum, and L. rhamnosus showed strong anti-Candida activity. These findings suggest that these lactobacillus strains may be used in probiotic products for the treatment and prevention of vulvovaginal infections in women.