Antifungal neoflavonoids from the farina of Pityrogramma trifoliata

ANA MARIA RODRIGUEZ; MARCOS DERITA; SUSANA ZACCHINO; BARDON ALICIA DEL VALLE; CECILIA SOCOLSKY

Tokushima

Simposio; ISPSA 2015 TOKUSHIMA; 2015

Phytochemical Society of Asia

Pityrogramma trifoliata (L.) R. M. Tryon is a farinose fern thatproduces both yellow and white farina. Despite of this obvious phenotypic difference, this species wasnot divided into varieties. The color of the farina is closely related to its chemical composition.Yellow farina is usually constituted by chalcones and may also point to thepresence of flavonols, whereas white farina contains mainly dihydrochalcones, flavanones or flavones [1]. Theyellow farina of P. trifoliata waspreviously analyzed, yielding three neoflavonoids named T-1 to T-3 (1-3) as minor constituents [2]. However, the absolute configuration of thesenatural products was not assigned.Flavonoids are known to display antifungalactivity against different pathogenic fungi [3a,b]. Since flavonoids arepresent in ferns' farina, we decided to evaluate the antifungal effect of the extracts of P. trifoliata againstdermatophyte fungi. The extracts of both the yellow and white farina displayed strong activity, which was comparable tothat of commercial antifungal agents like amphotericin B andketoconazole. Bioguided fractionation of the mentioned extracts yielded severalantifungal neoflavonoids (1, 2, 4-6).