Phytochemical screening and in vitro evaluation of anticandidal activity of Dodonaea viscosa (L.) Jaeq. (Sapindaceae)

The activity of fractions derived from hydroalcoholic extract of Dodonaea viscosa leaves against Candida albicans (Cl. I. 4043) was evaluated. The hydroalcoholic extract was sequentially fractionated to give n-hexane, dichloromethane, ethylacetate and n-butanol fractions that were subjected to qualitative phytochemical analyses. Disk diffusion assay was used in preliminary anticandidal screening with clotrimazole and chloroform serving as positive and negative controls, respectively. Optimized solvent systems were used for thin layer chromatography (TLC) that was followed by contact bioautography to evaluate the bioactivities of the fractions. Using broth microdilution technique, minimum inhibitory concentrations (MIC) of the individual fractions were established. With the exception of aqueous fraction all the fractions exhibited anticandidal activities (zone of inhibition = 10 mm) in preliminary screening against test yeast. However, n-hexane fraction showed two inhibition zones at Rf = 0.14 and 0.60 in contact bioautography, which indicates location of inhibitory compounds. The MIC of 62.5 mu g/ml also supports the presence of anticandidal moieties in n-hexane fraction. Flavonoids, terpenoids, tannins and steroids were the main metabolites indicated in phytochemical screenings.