African Journal of Biotechnology Vol. 6 (10), pp. 1197-1201, 16 May 2007   

ISSN 1684–5315 © 2007 Academic Journals        

Full Length Research Paper

Chemical constituents and antioxidant activity of Alstonia boonei

Afolabi C. Akinmoladun¹*, E. O. Ibukun¹, Emmanuel Afor ¹, B. L. Akinrinlola¹, T. R. Onibon¹, A. O. Akinboboye¹, E. M. Obuotor ² and E. O. Farombi ³.

¹Department of Biochemistry, Federal University of Technology, Akure, Nigeria.

²Department of Biochemistry, Obafemi Awolowo University, Ile-Ife, Nigeria.

³Drug Metabolism and Toxicology Unit, Department of Biochemistry, University of Ibadan, Ibadan, Nigeria.

*Corresponding author. E-mail: akinmoladunfc@yahoo.com.  Phone: +234 803444 5893.   

Accepted 23 March, 2007

The chemical composition and some antioxidant indices of Alstonia boonei stem-bark extract were evaluated. A. boonei was found to contain important minerals like calcium, phosphorus, iron, sodium, potassium, and magnesium. Alkaloids, tannins, saponins, flavonoids and cardiac glycosides were among the phytochemicals detected together with the important vitamin, ascorbic acid. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, total phenolic content and reducing power were 41.58 ± 1.43 %, 2.09 ± 0.04 mg/g gallic acid equivalent and 0.32 ± 0.01 respectively. Against the backdrop of the many medicinal uses of the plant, the results of the present work indicate that phytochemicals, other than phenolics, the mineral elements and vitamin C may be the critical factors in the medicinal effects of A. boonei.

Key words: Alstonia boonei, antioxidants, minerals, phytochemicals, medicinal effects.