In vitro Evaluation of Anti-hyperglycaemic Activity of Medicinal Plants Traditionally Used in Sikkim, North East India

Sikkim in North East India, has a rich ethnomedicinal practice and a large proportion of the local people rely on medicinal plants for the management of diabetes. Anti-hyperglycaemic effect of ten medicinal plants traditionally used by the local population in Sikkim to treat diabetes was evaluated using two in vitro methods – glucose uptake in yeast cells and α-amylase inhibition assay. Most of these medicinal plants demonstrated anti-hyperglycaemic effect, amongst which the leaves of Catharanthus roseus and Nyctanthes arbor-tristis displayed considerably greater activity than the other plant extracts. Both C. roseus and N. arbor-tristis showed greatest increase in glucose uptake at 25 mM glucose concentration (80.20% ± 3.01 and 78.83% ± 2.66 respectively), and maximum α-amylase inhibition of 72.29% ± 0.58 (IC₅₀ = 154.30 mg/ml) and 69.98% ± 1.16 (IC₅₀ = 150.48 mg/ml) respectively at 250 mg/ml concentration of the extracts. The values were comparable to the standard drugs. Ethno­medicinal practices largely rely on observations, experience and regional beliefs. Support from scientific assessment studies will not only encourage traditional practices in the region, but also contribute in the deve­lopment of alternative drugs of natural origin for diabetes