Control of Cryptococcus Gattii Biofilms by an Ethanolic Extract of Cochlospermum Regium (Schrank) Pilger Leaves

Cryptococcus gattii is an etiologic agent of cryptococcosis and a serious disease that affects immunocompromised and immunocompetent patients worldwide. The therapeutic arsenal used to treat cryptococcosis is limited to a few antifungal agents, and the ability of C. gattii to form bioflms may hinder treatment and decrease its susceptibility to antifungal agents. The objective of this study was to evaluate the antifungal and antibioflm activities of an ethanolic extract of Cochlospermum regium (Schrank) Pilger leaves against C. gattii. The antifungal activity was assessed by measuring the minimum inhibitory concentration (MIC) using the broth microdilution technique and interaction of the extract with fuconazole was performed of checkerboard assay. Te antibioflm activity of the extract was evaluated in 96-well polystyrene microplates, and the bioflms were quantifed by counting colony forming units. The extract showed antifungal activity at concentrations of 62.5 to 250 �g/mL and when the extract was evaluated in combination with fuconazole, C. gattii was inhibited at sub-MIC levels. The antibioflm activity of the extract against C. gattii was observed both during bioflm formation and on an already established bioflm. The results showed that the ethanolic extract of the leaves of C. regium shows promise for the development of antifungal drugs to treat cryptococcosis and to combat C. gattii bioflms.