Antifungal activity of clinical <i>Lactobacillus</i> strains against <i>Candida albicans</i> biofilms: identification of potential probiotic candidates to prevent oral candidiasis

<p>This study isolated <i>Lactobacillus</i> strains from caries-free subjects and evaluated the inhibitory effects directly on three strains of <i>C. albicans</i>, two clinical strains and one reference strain<i>.</i> Thirty <i>Lactobacillus</i> strains were isolated and evaluated for antimicrobial activity against <i>in vitro C. albicans</i> biofilms. <i>L. paracasei</i> 28.4, <i>L. rhamnosus</i> 5.2 and <i>L. fermentum</i> 20.4 isolates exhibited the most significant inhibitory activity against <i>C. albicans</i>. Co-incubation between these microorganisms resulted in deterrence of biofilm development and retardation of hyphal formation. The hindrance of biofilm development was characterized by the downregulated expression of <i>C. albicans</i> biofilm-specific genes (<i>ALS3</i>, <i>HWP1</i>, <i>EFG1</i> and <i>CPH1</i>). <i>L. paracasei</i> 28.4, <i>L. rhamnosus</i> 5.2 and <i>L. fermentum</i> 20.4 demonstrated the ability to exert antifungal activity through the inhibition of <i>C. albicans</i> biofilms.</p>