Bioassay-guided isolation of antifungal and antibacterial compounds of propolis from San Juan province, Argentina.

LIMA B,; TAPIA A,; JUAREZ S; WUNDERLIN D,; ZACCHINO S,; SCHMEDA-HIRSCHMANN G; FERESIN G.E.

Potrero de los Funes, San Luis. Argentina.

Congreso; XXIV Congreso Anual de la Sociedad de Biología de Cuyo; 2006

Sociedad de Biología de Cuyo

Since a crude methanolic extract of propolis (EMP) from Iglesia district showed a strongest antifungal and antibacterial activity by agar dilution method a study was undertaken to isolate and identify the main active metabolites from Propolis of San Juan. EMP (32g) was applied to a Sephadex LH-20 column.Some eigth fractions were obtained. The fraction VI (260 mg) was applied to a. After TLC comparison six were obtained. Fractions 2, 3 and 4 were successively percolated by Sephadex LH-20 column to affording crysin, galangin and pinocembrin as main compound. Nuclear magnetic resonance (NMR) spectra of pure compounds were obtained using a Bruker spectrometer, operating at 400 MHz for 1H and 100 MHz for 13C. Microsporum gypseum Trichophyton rubrum andT. mentagrophytes were strongly inhibited by pinocembrin MIC= 31.2µg/ml. Yeast Candida albicans C. tropicalis Cryptococcus neoformans and Saccharomyces cerevisiae with MICs ranging from 62.5 to 250µg/ml. On the other hand, crysin, galangin and, pinocembrin were active  against both sensitive and resistant strains of Staphylococcus aureus methicillin-sensitive ATCC 29213, Staphylococcus aureus methicillin-resistant ATCC 43300, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 with MICs ranging from 500 to 1000µg/ml.