Influence of Biosurfactants from Probiotic Bacteria on Formation of

Biofilms were grown on preconditioned voice prostheses with biosurfactants obtained from probiotic bac-teria Lactococcus lactis 53 and Streptococcus thermophilus A in an artificial throat model. Both biosurfactants greatly reduced microbial numbers on prostheses and also induced a decrease in the airflow resistance that occurs on voice prostheses after biofilm formation. This study presents a promising strategy for prolonging the lifespan of voice prostheses. Voice prostheses are used for speech rehabilitation of pa-tients who have undergone a laryngectomy due to a malignant laryngeal tumor and need to breathe through a tracheostomy (1). The major drawback of voice prostheses involves their colonization within several weeks by a thick biofilm that con-sists of fungal and bacterial strains. This biofilm causes leakage of food and liquid, and it may block the valves and increase resistance to airflow (10), making it necessary to replace the prosthesis on average every 3 to 4 months. Prolonged admin-istration of antifungal agents to patients is undesirable becaus