Anti-diabetic activity of Mimosa pigra Linn (Fabaceae) methanol leaf extract on alloxan-induced diabetic rats

The leaves of Mimosa pigra have been reported in ethnobotany to be used for the management of the symptoms of diabetes. This study is to investigate the anti-diabetic activity of the methanol extract of the leaves of this plant. The leaves were dried, pulverized and macerated successively in n-hexane, acetone and methanol. The methanol extract (1 g/kg body weight) was evaluated in vivo for anti-diabetic activity using adult male Wistar albino rats. Alloxan (150 mg/kg b.wt.) was used for induction of hyperglycemia, and Metformin (2.5 mg/kg) was used as the standard oral hypoglycemic agent. Blood glucose levels were monitored with a glucometer. The data is presented as Standard deviation (±) of the mean of blood glucose levels (mg/dl), and analyzed using one way analysis of variance (ANOVA) at (p<0.05). The methanol extract of the leaves showed significant percent decrease (p<0.05) in blood glucose levels of 3.80, 7.15 and 10.35 %, at 60, 120 and 180 min, respectively, on Day 1. And from Day 2 to Day 7 there was a continued decrease of 10.75, 16.36, 22.09, 29.06, 33.4 and 36.67 %, respectively, compared to the control. For the same period, the standard drug Metformin demonstrated greater decreases of 24.45, 30.38, 37.37, 40.93, 46.18 and 52.30 %, respectively. Phytochemical screening revealed the presence of flavonoids and tannins in the methanol and acetone extracts, while saponins and triterpenes were present in both the hexane and methanol extracts. The presence of these metabolites could be responsible for the observed anti-diabetic activity of this plant.