Characterization and Evaluation of Vernonia amygdalina Extracts for its Antidiabetic Potentials

Author(s): Adewole Ezekiel, Ojo A, Ogunmodede O.T, Adewumi D.F, Omoaghe A.O, Jamshed I

Background: There is increase in the demand for the use of medicinal plants for the treatment of various ailments such as cancer, hypertension and diabetes locally as a result of the inability of the synthesized drugs to completely eradicate the ailments and also with the attendant side effects attached to the use of drugs. Objective: The aim of this research work was to investigate the Aldose reductase, α-glucosidase, β -glucosidase and maltase glucoamylase inhibitory potential of the crude extracts of Vernonia amygdalina, and characterizing the extracts. Materials and method: The leaves of the plant was obtained, air dried and turned to powdered form using commercial grinding machine with dimension 34×38×75. The extracted crudes were subjected into in-vitro studies of the inhibitory potentials using recommended protocols. The IC50 values were calculated using Graph pad prism 5.0 software and the identified compounds were screened for drug properties using ONLINE OSIRIS server explorer. Results: The (IC50 0.6 ± 0.03 μg/mL) of the chloroform extract was better than the methanolic extract of IC50 (1.532±0.63μg/mL) and the results were better than the acarbose standard (IC50 234.6 + 2.01μM). The maltase glucoamylase inhibitory potentials of the chloroform and methanolic extracts in the range of IC50 1.112 ± 0.90 μg/mL and 1.315 ± 0.7 μg/mL. The β-glucosidase screening of the extracts results indicated that they do not have good selective inhibitor properties. IC50 of Aldose reductase (ALR2) of chloroform extract IC50 (1.339+0.264μg/mL) was better than that of methanolic extract of IC50 (1.437+0.6μg/mL) and these values were better when compared with the standard, sorbinil of IC50 (3.10 +0.20μM).The aldehyde reductase (ALR1) of methanolic extract IC50 (0.325+0.02μg/mL) was better than that of chloroform extract of IC50 (0.964+0.16μg/mL) and when compared with standard 10mM vaproic acid IC50 (57.4 +10μM).The GC-MS of the chloroform extract revealed compounds which were screened computationally to for various drug properties such as drug likeness, cLogS, cLogP, H-bond acceptor and H-bond Donor. Conclusion: The promising inhibitory potential of the plant extracts and characterization of the extract is an indication of the usefulness of the plant for the treatment of diabetes.

Diabetes mellitus, drug properties, aldose reductase, α-glucosidase, maltase glucoamylase, β-glucosidase

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