Anti-hyperglycemic and antioxidant potential of Croton bonplandianus. Bail fractions in correlation with polyphenol content

OBJECTIVE(S): Diabetes mellitus, a carbohydrate metabolic disorder, occurs due to absolute or relative deficiency of insulin. Current treatment strategies involve either preventing or delaying the intestinal absorption of glucose to lower the levels of postprandial hyperglycemia (PPHG). Herbal remedies have been since ancient times for treating diabetes mellitus. Therefore, identifying novel phytocompounds with α-amylase and α-glucosidase inhibitory activity that would reduce the glucose absorption as well as the rise in postprandial blood glucose level is vital. Consequently, the present study was aimed to investigate the anti-hyperglycemic activity of Croton bonplandianus against these pancreatic enzymes. MATERIALS AND METHODS: The methanol extract of C. bonplandianus leaf was prepared and further fractionation was performed with n-hexane, ethyl acetate and chloroform. The antioxidant activity and anti-hyperglycemic activity of the extracts and its fractions were determined. Further, GC-MS analysis was performed for the leaf extract. RESULTS: The chloroform fraction (ChF) was found to contain highest quantity of polyphenols (114.28 µg/ml of GAE), flavonoids (95.68 µg/ml of quercetin) and tannins (63.80 µg/ml of GAE) and also possessed effective inhibitory activity against α amylase (IC(50)95.78 µg/ml) and α glucosidase (IC(50) 126.81µg/ml). The antioxidant activity of ChFwas also higher when compared to other fractions. Further, GC-MS analysis of ChF showed the presence of various components that may be responsible for the above mentioned activities. CONCLUSION: The study findings suggest that the components present in the leaves of C. bonplandianus, may provide a potential therapeutic source in developing treatment forhyperglycemia. Further bioassay guided fractionation procedure is required to identify the active constituents.