Kinetics of inhibitory effect of ethyl acetate leaf fraction of Lecaniodiscus cupanoides on enzymes linked to carbohydrate metabolism: An in vitro assessment

Document Type: Original Article


1 Department of Botany, Obafemi Awolowo University, Ile-Ife, Nigeria .

2 Department of Pure and Applied chemistry, Usmanu Danfodiyo University Sokoto, Nigeria.

3 Department of Microbiology, University of Kwazulu Natal, Westville Campus, South Africa

4 Department of Botany, Obafemi Awolowo University, Ile-Ife, Nigeria 220005,

5 Department of Chemistry, Obafemi Awolowo University, Ile-Ife, Nigeria 220005,


Background and aims: This study investigates the kinetics of inhibitory activities of ethyl acetate leaf fraction of Lecanodiscus cupanoides on 𝛼-amylase and 𝛼-glucosidase.
Methods: This was done using 𝛼-amylase and 𝛼-glucosidase enzymes from Aspergillus oryzae and Saccharomyces cerevisiae respectively, active component and antioxidants capabilities of the fraction were also analyzed.
Results: The fraction scavenged DPPH, OH*, and ABTS+ and chelated Fe2+ with the IC50 values of 0.46, 0.70, 0.75 and 0.97 mg/mL respectively. However, significant and mild inhibitory effect was also observed in 𝛼- amylase and glucosidase with IC50 values (0.73 and 0.58 mg/mL) in concentration dependent pattern. Kinetic analysis of the fraction revealed an uncompetitive and non-competitive mode of inhibition for 𝛼-amylase and 𝛼-glucosidase respectively.
Conclusion: This study suggests that ethylacetate fraction of this plant possesses antidiabetic property as a result of its ability to inhibit the metabolism of carbohydrate hydrolyzing enzymes. The elicited activities of the ethyl acetate fraction Lecanodiscus cupanoides may be due to the presence of phytochemicals of utmost pharmacological importance present in the fraction.


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