In vitro antioxidant potential and inhibitory effect of hydro-ethanolic extract from African black velvet tamarind (Dialium indium) pulp on type 2 diabetes linked enzymes


  • Olakunle Bamikole Afolabi Phytomedicine and Toxicology Laboratory, Biochemistry Unit, Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Omotade Ibidun Oloyede Department of Biochemistry, Ekiti State University, P.M.B 5363, Ado”‘Ekiti
  • Abiodun Ayodele Ojo Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Amos Adeyinka Onansanya Molecular and Biotechnology Laboratory, Biochemistry Unit, Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Shadrach Oludare Agunbiade Nutrition and Food Science Laboratory, Biochemistry Unit, Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Bashir Olaitan Ajiboye Phytomedicine and Toxicology Laboratory, Biochemistry Unit, Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Jonathan Johnson Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State
  • Omolara Abosede Peters Department of Chemical Science, College of Science, Afe-Babalola University. P.M.B 5454, Ado- Ekiti, Ekiti State



Type 2 Diabetes, α-amylase, Dialium indium, α-glucosidase, antioxidant


The alarming rate of diabetes mellitus (DM) globally is bothersome and has drawn the search light of researchers on naturally endowed phytonutrients being an alternative in managing the menace. Therefore, the current study was designed to investigate some antioxidant parameters embedded in the extract of Dialium indium (DI) fruit pulp and also, to elucidate its antidiabetic potentials through the inhibition of two key carbohydrate-metabolizing enzymes such as α-amylase and intestinal α-glucosidase. Hydro-ethanolic extract of DI fruit pulp was used for the antioxidants and enzyme inhibitory bioassays through various convectional antioxidant assay methods in vitro. In the results, total phenolic content of the extract had; 6.74 ±3.38 mg GAE.g-1, total flavonoid contents; 0.02 ±0.01 mg QE.g-1 and FRAP; 0.84  ±0.47 mg AAE.g-1 dried sample. Also, there was a marked significant (p <0.05) difference observed in the inhibition of α-amylase and intestinal α-glucosidase by the different concentrations of the extract used in concentration-dependent manner with their different EC50. The inhibition demonstrated against these two carbohydrate metabolizing enzymes possibly could be through the embedded antioxidant potentials of the fruit pulp and this if properly harnessed, it could be helpful in the management of type 2 diabetes.


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How to Cite

Afolabi, O. B., Oloyede, O. I., Ojo, A. A., Onansanya, A. A., Agunbiade, S. O., Ajiboye, B. O., Johnson, J. ., & Peters, O. A. (2018). In vitro antioxidant potential and inhibitory effect of hydro-ethanolic extract from African black velvet tamarind (Dialium indium) pulp on type 2 diabetes linked enzymes. Potravinarstvo Slovak Journal of Food Sciences, 12(1), 413–421.