Flavonoids from Acacia saligna leaves and Evaluation of Antihyperglycaemic Effect of Aqueous Extract

Diabetes mellitus is a chronic disease caused by inherited and/or acquired deficiency in production of insulin by pancreas, or by the ineffectiveness of the insulin produced. The present study deals with the isolation and identification of flavonoids from Acacia saligna (Labil L.) H.L. Wendel. leaves and evaluation of antihyperglycaemic effect of aqueous alcoholic extract. The aqueous alcoholic extract (MeOH: H₂O, 7: 3) of Acacia saligna leaves was subjected to extensive repeated Column chromatography on polyamide, cellulose and Sephadex LH-20 resulted in myricetin 3-O-β-arabinopyranoside, quercetin 3-O-β-arabinopyranoside, luteolin 7-O-β-arabinopyranoside, myricetin 3-O-α-L-rhamnopyranoside, quercetin 3-O-α-L- rhamnopyranoside, myricetin 3-O-β-glucopyranoside, quercetin 3-O-β-glucopyranoside, luteolin 7-O-β-glucopyranoside, luteolin, quercetin and myricetin. The structure of the isolated compounds was elucidated on the basis of spectral analysis. The effect of the oral treatment with dry aqueous alcoholic extract of Acacia saligna leaves (30mg/kg for 21 days) on serum glucose in normal and alloxan-induced diabetic rats is reported. Fasting blood glucose levels of diabetic rats were significantly (P<0.01) higher than those in normal rats. A significant decrease in blood glucose level was observed in diabetic rats treated with the extract of Acacia saligna leaves from an initial level of (255.6±20.8) to (117.8±10mg/dL). The extract failed to produce hyperglycemic activity in normal treated rats. The chemical constituents of plant especially flavonoids and other compounds present in the plant may be involved in the observed hypoglycemic effect of the plants extract [1]. The results show that the oral administration of Acacia saligna leaves extract on the diabetic state reducing hyperglycemia.

Reference: 1. Resurreccion-Mago, M.H., Villasenor I.M. et al. (2005), Phytother. Res. 19: 246–251.