International Journal of Phytotherapy and Ethnobotany ISSN 4536-1835 Vol. 3 (2), pp. 080-0084, February, 2016. © International Scholars Journals

Full Length Research Paper

A study of phenolic compounds by methanolic extracts of some medicinal plants

Dzingirai, B. 2, Muchuweti, M1* , Murenje, T.1, Chidewe, C.1, Benhura, M.A. N and Chagonda, L. S2.

1Department of Biochemistry, University of Zimbabwe, M.P. 167, Mount Pleasant, Harare, Zimbabwe.

2Department of Pharmacy, College of Health Sciences, University of Zimbabwe, M.P. 167, Mount Pleasant, Harare, Zimbabwe.

*Corresponding author. E-mail: muchuweti@medic.uz.ac.zw. Tel: 00263 (0) 4 308047, Fax: 00263 (0) 4 308046.

Accepted 14 December, 2015

Abstract

Two commonly known medicinal plants from Zimbabwe were analyzed for total phenolic content, superoxide radical scavenging activity and the ability to inhibit lipid peroxidation in rat brain extracts. The plant samples used in this study were Elionurus muticus and Hypoxis hemerocallidea. The Folin Ciocalteu method was used to determine the total phenolic content. The total phenolic content was high in H. hemerocallidea which had 0.268 ± 0.02 mg/100mg dry mass of plant extract and lowest in E. muticus root extract had 0.041 ± 0.03 mg/100mg dry mass of plant extract. The scavenging activities on the superoxide ion of the plant extracts was dose dependent with maximum scavenging activity being obtained from E. muticus whole plant (69.12% ± 0.12 at 80 mg/ml) and the least activity were detected in H. hemerocallidea (52.92% ± 0.95 at 80 mg/ml). The plant extracts also gave a dose dependent protection against lipid peroxidation in rat brain homogenate with the highest protection detected from E. muticus whole plant and the least from H. hemerocallidea.

Key words: Phenolic compounds, medicinal plants, phospholipid peroxidation.