Hypoglycaemic activity of four plants used in Chilean popular medicine

The hypoglycaemic activity of a 20% dried leaf infusion of Bauhinia candicans Benth. (Leguminosae), Galega officinalis L. (Leguminosae), Morus alba L. (Moraceae) and Rubus ulmifolius Schott. (Rosaceae), used for diabetes in Chilean popular medicine, was evaluated in alloxan and streptozotocin induced hyperglycaemic rats. In normal rats the different infusions did not modify significantly the glycaemia in the period studied, but in diabetic rats different results were observed, depending on the diabetogenic drug used. B. candicans and R. ulmifolius infusions elicited remarkable hypoglycaemic effects in both experimental models. B. candicans presented a greater decrease of glycaemia in alloxan diabetic rats (39%) and R. ulmifolius showed a similar activity in both alloxan and streptozotocin diabetic rats (28% and 29%). Activity-guided fractionation of R. ulmifolius showed that petroleum ether extracts elicited a marked hypoglycaemic effect (35%) in the streptozotocin induced model.