Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Effect of Senna alata (L) Roxb (Fabaceae) leaf extracts on alpha-amylase, alpha-glucosidase and postprandial hyperglycemia in rats

Mutiu I Kazeem, Ganiyat A Azeez, Anofi OT Ashafa

Phytomedicine and Phytopharmacology Research Group, Department of Plant Sciences, University of the Free State, Qwaqwa Campus, Phuthaditjhaba 9866, South Africa;

For correspondence:- Anofi Ashafa Email: ashafaaot@qwa.ufs.ac.za Tel:+27587185134

Received: 17 July 2014 Accepted: 22 July 2015 Published: 31 October 2015

Citation: Kazeem MI, Azeez GA, Ashafa AO. Effect of Senna alata (L) Roxb (Fabaceae) leaf extracts on alpha-amylase, alpha-glucosidase and postprandial hyperglycemia in rats. Trop J Pharm Res 2015; 14(10):1843-1848 doi: 10.4314/tjpr.v14i10.15

© 2015 The authors.
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Abstract

Purpose: To investigate the inhibitory effect of S. alata leaf extracts on α-amylase and α-glucosidase, and its potential for reducing postprandial blood glucose level of rats.

Methods: The α-amylase and α-glucosidase inhibitory potentials of acetone, ethylacetate and hexane extracts of S. alata were investigated by reacting different concentrations (0.63 – 10.0 mg/mL) of the extracts with the enzymes and substrates while the mode(s) of inhibition of both enzymes were determined using the Lineweaver-Burk plot. The effect of oral administration of the hexane extract (with lowest IC₅₀ for α-glucosidase) of the plant in sucrose-induced hyperglycemic rats was also determined by evaluating fasting blood glucose levels.

Results: The acetone extract of S. alata displayed the highest inhibitory activity against α-amylase (IC₅₀ = 6.41 mg/mL) while hexane extract exhibited highest inhibitory effect on α-glucosidase (IC₅₀ = 0.85 mg/mL). Both acetone and hexane extracts inhibited α-amylase and α-glucosidase in a competitive and uncompetitive manner respectively. The hexane extract of S. alata also caused significant reduction (p < 0.05) in the postprandial blood glucose level of sucrose-loaded rats within two hours.

Conclusions: It can be suggested that one of the mechanisms of anti-diabetic action of S. alata leaf is the inhibition of intestinal α-glucosidase.

Keywords: Senna alata, Diabetes, Postprandial hyperglycemia, Phytochemicals, alpha-glucosidase, alpha-amylase