Nordihidroguaiaretic Acid isolated from Larrea divaricata: bioactivity against Candida spp. from human clinical samples

OLARTE C.; TORRES C.; TONN C.; SUTIL S.; ESCOBAR F.; ZANON S.; SABINI L.

Huerta Grande. Córdoba

Encuentro; Primera Reunión Conjunta de Sociedades de Biología de la República Argentina; 2007

Plants constitute the principal source for the search of new drugs with pharmacological activity. Nordihidroguaiaretic Acid (NDGA) of Larrea divaricata exhibits antioxidant, antibacterial and antiviral action. The aim of this work was to determine antifungal capacity against Candida spp. strains. This property was evaluated by microdilution technique, M27-A on 6 strains of Candida spp. isolated from clinical human cases of vaginal, respiratory and urinary candidiasis. Minimal Inhibitory Concentration (MIC), 50 % Inhibitory Concentration (IC50) (software Origin 7.5) and Minimal Fungicidal Concentration (MFC) were determined. All assays were carried out by duplicate. The ten concentrations (50-500μg/ml) that were analyzed inhibited all the strains in different grades. The IC50 had values between 217 and 405 μg/ml and they revealed that strains number 4 (sputum) and 6 (vaginal exudate) were the most sensitive, and strain 2 (urine) exhibited the greatest resistance to the compound action. Values of MFC for any strain were not found. These results permit conclude that NDGA exerted fungistatic action for all strains studied.