The Effect of Zuccagnia punctata, an Argentine Medicinal Plant, on Virulence Factors from Candida Species

Zuccagnia punctata Cav, has been used as a traditional medicine in Argentina for the treatment of bacterial and fungal infections. In this study, we evaluated the ability of Z. punctata extract (ZpE) and compounds isolated from it to inhibit the growth and virulence factors of Candida species. ZpE showed inhibitory activity against planktonic cells of all assayed Candida species with MIC values of 400 mu g/mL and with MFC values between 400 and 1,200 mu g/mL. The principal identified compounds by HPLC-MS/MS and UV-VIS were chalcones (2',4'-dihydroxy-3'-methoxychalcone, 2',4'-dihydroxychalcone), flavones (galangin, 3,7-dihydroxyflavone and chrysin) and flavanones (naringenin, 7-hydroxyflavanone and pinocembrine). These compounds were more effective as inhibitors than the extracts upon biofilm formation as well as on preformed Candida biofilm and yeast germ tube formation. Furthermore, ZpE and chalcones are able to inhibit exoenzymes, which are responsible for the invasion mechanisms of the pathogens. All these effects could moderate colonization, thereby suppressing the pathogen invasive potential. Our results indicate that ZpE and chalcones could be used in antifungal therapy.