en عمومى General پژوهشي Research <p><strong>Background:</strong> Diabetes mellitus is a chronic disease. Decreasing postprandial hyperglycemia by retarding glucose absorption through inhibiting carbohydrates digesting enzymes (&alpha;-amylase and &alpha;-glucosidase) is one of many approaches used for the management of this disease. This study was aimed at evaluating the normoglycaemic potential of <em>Helianthus annuus </em>leaf.</p> <p><strong>Methods:</strong> The effect of the <em>in vitro </em>inhibitory of different extracts (acetone, ethyl acetate and hexane) of the plant was assessed on the activities of diabetes-related enzymes (&alpha;-amylase and &alpha;-glucosidase).</p> <p><strong>Results:</strong> The hexane extract of <em>H. annuus </em>leaf displayed the best inhibitory activity against &alpha;-amylase and &alpha;-glucosidase as indicated by the IC₅₀ values (3.92 &plusmn; 0.02 mg mL^-1) and (3.29 &plusmn; 0.12 mg mL^-1), respectively. Lineweaver-Burk plot of inhibition of &alpha;-amylase and &alpha;-glucosidase by this extract showed that it was competitive and non-competitive mode, respectively.</p> <p><strong>Conclusion:</strong> <em>H. annuus </em>leaf possesses hypoglycaemic potential which may be due to the inhibition of pancreatic &alpha;-amylase and intestinal &alpha;-glucosidase.</p> Helianthus annuus, postprandial hyperglycaemia, α-amylase, α-glucosidase α-Amylase, α-Glucosidase, Helianthus Annuus, Postprandial Hyperglycaemia. 17 22 http://ijt.arakmu.ac.ir/browse.php?a_code=A-10-371-1&slc_lang=en&sid=1 Oluwafemi Adeleke Ojo oluwafemiadeleke08@gmail.com 10031947532846005511 10031947532846005511 Yes Department of Biochemistry, Afe Babalola University, Ado-Ekiti, Nigeria. Adebola Busola Ojo 10031947532846005512 10031947532846005512 No Department of Biochemistry, Ekiti State University, Ado-Ekiti, Nigeria. Basiru Ajiboye 10031947532846005513 10031947532846005513 No Department of Biochemistry, Afe Babalola University, Ado-Ekiti, Nigeria. Israel Olayide 10031947532846005514 10031947532846005514 No Department of Biochemistry, Afe Babalola University, Ado-Ekiti, Nigeria. Adewale Fadaka 10031947532846005515 10031947532846005515 No Department of Biochemistry, Afe Babalola University, Ado-Ekiti, Nigeria.