In vitro hypoglycaemic effects of some Salvia species from Iran

Diabetes mellitus is one of the most serious chronic diseases characterized by chronic hyperglycaemia [1]. Inhibitors of carbohydrate hydrolyzing enzymes play an important role in the control of postprandial hyperglycaemia, especially in type 2 diabetes, through retarding of absorption of meal-derived glucose [2,3]. Some of Salvia species are advocated in traditional Iranian medicine to possess antidiabetic activities [4]. In order to find a scientific validation of their traditional use, an in vitro α-amylase inhibition assay was performed on the extracts of some Salvia species

The ethanol extracts obtained from six Salvia species (S. hydrangea DC., S. hypoleuca Benth., S. officinalis L., S. reuterana Boiss., S. verticillata L. and S. virgata Jacq.) were tested against α-amylase and inhibitory activity of each extract, expressed as IC₅₀ values, calculated from Log concentration-response curve. As positive control acarbose was used. The results were statistically compared by one-way ANOVA to see the significance.

Two of the screened plants exhibited significant α-amylase inhibitory activity. IC₅₀ values of these plants were found to be 18.34 (18.07–18.61)mg/ml and 19.73 (19.30–20.17)mg/ml for S. verticillata and S. virgata, respectively. In conclusion, this study supports the traditional use of the genus Salvia in diabetes.

References: 1. Abesundara, K.J. et al. (2004)J. Agric. Food Chem. 52: 2541–1545.

2. Kim, Y.M. et al. (2005) Nutrition. 21: 756–761.

3. Kotowaroo, M.I. et al. (2006) Phytother. Res. 20: 228–231.

4. Amin, G. et al. (2005) Popular Medicinal Plants of Iran. Vice-chancellorship of Research, Tehran University of Medical Sciences. Tehran.