Antioxidant and antihyperglycemic activity of the medicinal specie Oreocallis grandiflora (Lam.) R. Br., in southern Ecuador

In this study we evaluated the antioxidant and antihyperglycemic activity in vitro of the extracts obtained with solvents: hexane, ethyl acetate and methanol, of the medicinal plant Oreocallis grandiflora (cucharillo), collected in the Saraguro indian community of the province Loja, southern Ecuador. The antioxidant activity was evaluated by the tests: DPPH, FOLIN-CIOCALTEU and beta-CLAMS, while the antihyperglycemic activity was determined by inhibition assay alpha-amylase and alpha-glucosidase. The samples were diluted to different concentrations and the reading was performed in a UV spectrophotometer, using as positive control alpha-tocopherol for DPPH and Folin-ciocalteu test, trolox for beta-CLAMS test, and Glucobay (R) for testing alpha-amylase and alpha-glucosidase. The results are expressed as IC50, these show that the methanol extract of Oreocallis grandiflora has inhibitory effect on alpha-amylase, the IC50 is 109 mu g/ml, compared to 126 mu g/ml of Glucobay (R). It also shows inhibitory effect on alpha-glucosidase, the IC50 is 3 mu g/ml compared to 1316 mu g/ml of Glucobay (R). It also shows antioxidant activity, its IC50 is 15 mu g/ml compared to 5 mu g/ml of alpha-tocopherol.