Comparative Studies of the Effects of Five Indigenous Cowpea (Vigna unguiculata) Varieties on Enzymes Linked to Type 2 Diabetes and their Glycemic Indices

Ganiyu. Oboh, Gbenga P. Akerele*, Bukola C. Adedayo, Adedayo O. Ademiluyi
Functional Foods and Nutraceutical Unit, Department of Biochemistry, Federal University of Technology, Akure, P.M.B. 704, Akure, 340001, Nigeria
Corresponding Author: [email protected] ; Tel: +234-7030189434
Recieved Date: 02 March 2021; Accepted Date: 13 May 2021; Published Date: 03 June
Citation: Oboh G, Akerele GP, Adedayo BC, Ademiluyi AO. Comparative Studies of the Effects of Five Indigenous Cowpea (Vigna unguiculata) Varieties on Enzymes Linked to Type 2 Diabetes and their Glycemic Indices. Trop J Nat Prod Res. 2021; 5(5):970-976.
 © 2021 Oboh et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Visit for more related articles at  Tropical Journal of Natural Product Research


Studies have supported the consumption of cowpea as a low glycemic index (GI) diet especially in managing diabetes. This study investigated the glycemic indices of five varieties of cowpea (Kano white, Sokoto white, Drum, Ife brown and Oloyin varieties) commonly consumed in Nigeria. The starch and sugar contents showed Sokoto white variety had the lowest starch and sugar (2.5 g/100 g, 9.02 g/100 g; 15.58 g/100 g, 26.69 g/100 g) content for both the raw and cooked samples, respectively, while the glycemic index ranged from 69.01 (Drum variety) to 77.08 (Oloyin variety). Furthermore, the cowpea extracts showed high antioxidant properties as revealed by their ferric reducing and  radical scavenging abilities. Also, the cowpea varieties showed their ?-amylase and ?-glucosidase inhibitory potentials with Kano white variety (IC50 = 0.33 mg/mL), showing the highest ?-amylase inhibitory potential when raw and Ife brown (IC50 = 0.37 mg/mL) when cooked, while Sokoto white variety (IC50 = 0.48 mg/mL) the lowest when raw and Oloyin variety (IC50 = 0.83 mg/mL) when cooked. However, Drum variety had the highest ?-glucosidase inhibitory activity (IC50 = 0.66 mg/mL) while Oloyin had the highest (IC50 = 0.33 mg/mL) when cooked with Sokoto white variety (IC50 = 0.93 mg/mL; IC50 = 0.70 mg/mL) having the lowest for both the raw and cooked samples respectively. The low glycemic index of Sokoto white variety, its antioxidant properties as well as its ?-glucosidase and ?-amylase inhibitory activities could make it the most suitable variety as a diet for the management of diabetes.

Keywords: Cowpea varieties, ?-amylase, ?-glucosidase, Glycemic indices.
Back to Articles

ISSN: 2616-0684 (Print)
ISSN: 2616-0692 (Online)
DOI: 10.26538/tjnpr
Index Copernicus Value (ICV) for 2017: 59.83
Scopus citescore 0.3 (2020)

Indexing & Abstracting

citescore 0.3 (2020)

j-gate logo

International Innovative Journal Impact Factor

African Index Medicus


Index Copernicus International

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License

Crossref Content Registration logo

WorldCat Discovery Service

Geneva Foundation for Medical Education and Research