Antifungal Activity of Polymers with Plant Extracts on Candida Biofilm

Objectives: The aim is evaluate the antifungal activity of Thymus vulgaris, Croton lechleri and Julliana adstringens Schl. added to Chitosan and Pullulan biopolymers against Candida albicans biofilm formation. Methods: Different parts of these plants were collected and extracted with solvents to obtain aqueous and organic extracts. These extracts were added to biopolymers in concentrations about 10% to T. vulgaris, 11% J. adstringens Schl. and 20% C. lechleri. The polymers were used at 1% Chitosan and 10% Pullulan. This study makes use of a 96-well microtiter plate model of C. albicans biofilm formation to test the susceptibility of biofilms to the polymers with plant extracts. This model is coupled with a colorimetric XTT-reduction assay in which metabolically active sessile cells reduce a tetrazolium salt to water-soluble orange formazan compounds, and the intensity this product can be determined using a microtiter-plate reader. Results: Pullulan added with J. adstringens Schl. inhibited biofilm formation about 100%, while T. vulgaris showed low activity (2.5% biofilm inhibition), and C. lechleri inhibited biofilm formation about 52.5%. The Chitosan biopolymers showed activity with T. vulgaris and C. lechleri, with 51.5% and 44% biofilm inhibition, respectively. However, there was low activity using J. adstringens in Chitosan. Our finding showed that J. adstringens exhibited strong antifungal activities in C. albicans biofilm inhibition in Pullulan, while T. vulgaris and C. lechleri exhibited inhibitory effects in Chitosan . The biopolymers did not have any inhibitory effects on preformed C. albicans biofilms. Conclusion: Chitosan and Pullulan added with certain plant extracts have potential to be used as antifungal on Candida albicans biofilms.