Ammodaucus leucotrichus Coss. & Durieu: Antihyperglycemic activity via the inhibition of α-amylase, α-glucosidase, and intestinal glucose absorption activities and its chemical composition

Context: Ammodaucus leucotrichus commonly known as a ‘Kamune es sufi or akâman’ in Morocco, is used to treat many diseases including diabetes. Aims: To investigate the antihyperglycemic activity of an aqueous extract of fruits A. leucotrichus (AEAL) and its chemical composition. Methods: The antihyperglycemic effect of the AEAL was tested against intestinal α-glucosidase and pancreatic α-amylase activities, in vitro, at the concentrations (41-328 µg/mL) and (0.5-3 mg/mL) respectively. In addition, the inhibitory effect of the AEAL (150 mg/kg) against these enzymes was confirmed, in vivo in normal and alloxan diabetic rats using sucrose, starch, and glucose as a substrate.The antihyperglycemic effect of the AEAL was also tested against intestinal D-glucose absorption activity at the dose of 150 mg/kg using the jejunum segment perfusion technique, in situ. Chemical composition was evaluated using HPLC. Results: The results of this study showed that the AEAL was significantly (p<0.001) inhibited the intestinal α-glucosidase, in vitro (IC50 = 0.254 mg/mL). The same effect of this extract was confirmed against the pancreatic α-amylase activity, with IC50 = 1.81 mg/mL. In vivo, the oral intake of the AEAL at a dose of 150 mg/kg was significantly attenuated the hyperglycemia induced by the sucrose, starch, and glucose in the normal and alloxan diabetic rats. AEAL, also, significantly (p<0.01) decreased intestinal glucose absorption, in situ.HPLC results revealed the presence of four molecules: vanillin, quercetin, kaempferol, and thymol. Conclusions: A. leucotrichus showed a significant antihyperglycemic activity. This effect can be explained by the inhibition of α-amylase, α-glucosidase activities, and the intestinal absorption of D-glucose.