Antifungal activity of Euphorbia prostrata (Aiton) ethanolic/aqueous extract against Candida albicans strains

SOBERÓN, J.R.; SGARIGLIA, M.A.; JIMENEZ, C.M.; ANDINA, M.L.; AGUILAR, F.A.; PASTORIZA, A.C.; VILLAFAÑE, F.R.; SAMPIETRO, D.A.; VATTUONE, M.A.

Hyderabad

Congreso; International Conference and Exhibition on Traditional & Alternative Medicine; 2013

OMICS Group

Candida albicans is referred as opportunistic pathogen yeast which causes infections in immunocompromised or transplanted patients. Current antifungal drugs possess high toxicity (polyenes), fungistatic action and resistance development (azoles), high costs (echinocandins) or access difficult for patients (pyrimidin analogs). Euphorbia prostrata (Aiton) has been described to possess anti-yeasts activities in folk medicine. An ethanolic/aqueous extract from E. prostrata aerial parts (EPE) was prepared and assayed by disk diffusion assays in modified Mueller-Hinton agar, alone between 62.5-500 µg of extracted material (EM) . disk-1 and combined with fluconazole (FLU) (1 µg . plate-1) against C. albicans ATCC 10231 (FLU sensitive) and C. albicans 12-99 (FLU resistant). The interaction of EPE with FLU was investigated by way of checkerboard tests on 96-well plates, with 48-h incubation for ATCC strain and 24-h incubation for 12-99 strain. The minimal inhibitory concentrations (MICs) and the factional Inhibitory Concentrations (FICs) were calculated. The MIC-0 (optically clear wells) criteria was used, considering MIC-0FLU=64 µg . mL-1 (≈3-log decrease in cell viability, determined by colony count assay). Disk diffusion assay results showed EPE exerted inhibitory effects on both C. albicans strains growth, even in FLU absence at quantities ranging from 500-125 µg EM . disk-1. EPE exert synergic effect when combined with FLU against ATCC strain (FIC=0.25), and no synergistic effect (additive) on 12-99 strain (FIC>0.5). These findings give the basis to perform experiments in order to identify and elucidate the chemical structures of EPE antifungal compounds. These experiments are currently under development.