Inhibition of Haemoglobin Glycosylation, Glucose Uptake and In Vitro Antidiabetic Activities of Solvent Fractions from Daucus carota Seed

Diabetes mellitus (DM) is a metabolic disorder which result from either absolute or relative insulin deficiency and may lead to dysfunction in some organ systems. Pancreatic α- glucosidase and α- amylase inhibition are an effective strategy to decrease levels of postprandial hyperglycemia through starch control breakdown. The aim of the study is to assess the in vitro antidiabetic activities of fractions from Daucus carota seed extract, a plant used traditionally for the treatment of diabetes mellitus. The aqueous extract (AQE) of Daucus carota seed was partitioned in ethyl acetate (EAE), n – hexane (HEX) and diethyl ether (DEE) to obtain the various fractions. The AQE and EAE expressed significant α – amylase inhibitory activity with IC₅₀ values of 637.0±18.6 μg/mL and 603.0±25.8 μg/mL respectively. AQE, EAE, HEX and DEE expressed α – glucosidase inhibitory activity with IC₅₀ value of 135.85±1.21, 147.59±0.57, 132.64±1.17, and 143.56±0.49 μg/mL respective compared with acarbose (ACA) with 5.42±0.20 μg/mL. Furthermore, DEE fraction expressed inhibitory effects on % glucose uptake in yeast cell comparable with metronidazole. All Daucus carota fractions expressed various inhibitory effects on haemoglobin glycosylation at a concentration of 200 – 1000 μg/mL. The results show that fractions from the aqueous seed extract of Daucus carota possess in vitro antidiabetic potentials with EAE and HEX fractions having most promising inhibitory activities against α-amylase and α-glucosidase respectively.