Inhibition activity of Lactobacilli supernatant against fungal-bacterial multispecies biofilms on silicone

Fungal-bacterial multispecies biofilms play a major role in failure of medical silicone devices, such as voice prostheses in laryngectomiy. In this study, we determined the effect of Lactobacilli supernatant (cell free) on mixed biofilm formation of fungi and bacteria on silicone in vitro. Lactobacilli supernatant inhibited the adhesion (90 min) of mixed fungi and bacteria species with an efficiency of > 90%. Mixed biofilm formation and the metabolic activity of the biofilms were inhibited by 72.23% and 58.36% by Lactobacilli supernatant. The examination using confocal laser scanning microscopy and scanning electron microscopy confirmed that Lactobacilli supernatant inhibited the growth of mixed biofilm and damaged the cells. Moreover, Lactobacilli supernatant also inhibited Candida yeast-to-hyphal transition. Therefore, Lactobacilli supernatant may serve as a possible antibiofilm agent to limit biofilm formation on voice prostheses.