Biodirected fractionation of ethanolic extracts of Phoradendron liga (Gill ex H.& Arn.) Eich. antifungal activity against lemon pathogenic fungi

SELIS DE ORSI, A.N.; SGROI, N.A.; SGARIGILA, M.A.; SOBERÓN, J.R.; QUIROGA, E.N.; VATTUONE, M.A.

Tucumán - Argentina

Congreso; XXV Annual Scientific Meeting of Tucuman Biology Society; 2008

Tucuman Biology Society (publicado en Bio Cell 33 (2))

Citrus (lemons) are attacked by fungi which produce large losses in post-harvest. Plants of  Northwestern Argentina produce antifungal substances. A biodirected study was performed to separate the active substances from Phoradendron liga. Ethanolic extracts, 10 % (p/v), from dry leaves were prepared, and assayed on Penicillum digitatum, P. expansum, Aspergillus niger and Geotrichum candidum growth. Antifungal activity was assayed by bioautography on Silica gel plates, and by radial growth inhibition. Extract fractionation was performed by extraction with solvents of increasing polarity (ethyl ether, dichlorometane and methanol). The most active fraction (methanolic) was fractionated by gel filtration on Sephadex LH 20.  Three main fractions (F1; F2; F3) were pooled. F2, the most active, was fractionated in five fractions (P1-P5) by Silica gel. P4 was selected to analyse its general composition with the purpose to determine the chemical structure of its components.