Hypoglycemic effect of quassinoids from Brucea javanica (L.) Merr (Simaroubaceae) seeds

Ethnopharmacological relevance: The seeds of Brucea javanica (L.) Merr (Simaroubaceae) are recommended by traditional practitioners for the treatment of diabetes mellitus. Aim of the study: To identify the compounds responsible for blood glucose lowering effect and evaluate the acute toxicity of the compounds. Materials and methods: Extracts. fractions and subfractions were administered to normoglycemic mice and the blood glucose concentration was monitored for 8 h. Bioactive compounds isolated through column chromatography were administered to normoglycemic mice and streptozotocin (STZ) rats with monitoring of blood glucose concentration at 0-8 h. The acute toxicity was evaluated in mice. Results: Bioactivity-guided fractionation led to the isolation of bruceines E (1) and D (2). Normoglycemic mice administered with 1 mg/kg of I and 2 exhibited significant blood glucose concentration reduction of 40.07 +/- 11.45% and 48.82 +/- 13.34%, respectively. STZ induced diabetic rats administered with 1 and 2 exhibited significant blood glucose concentration reduction of 73.57 +/- 13.64% and 87.99 +/- 2.91%. respectively. Conclusion: The reduction of blood glucose concentration by both bruceines was comparable to glibenclamide and they might act as an insulin secretagogue. The presence of a hydroxyl moiety at C-2 in 1 reduced the toxic effect by 9-fold compared to 2. (C) 2009 Elsevier Ireland Ltd. All rights reserved.