G A Ayoola1 ,
HAB Coker1,
S A Adesegun2,
A A Adepoju-Bello1,
K Obaweya1,
E C Ezennia1,
T O Atangbayila1
1Department of Pharmaceutical Chemistry,;
2Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Lagos, Nigeria..
For correspondence:- G Ayoola
Email: oyetayo68@yahoo.com Tel:+234-1-8940442
Published: 20 September 2008
Citation:
Ayoola GA, Coker H, Adesegun SA, Adepoju-Bello AA, Obaweya K, Ezennia EC, et al.
Phytochemical Screening and Antioxidant Activities of Some Selected Medicinal Plants Used for Malaria Therapy in Southwestern Nigeria.. Trop J Pharm Res 2008; 7(3):1019-1024
doi:
10.4314/tjpr.v7i3.3
© 2008 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..
Abstract
Purpose: Oxidative stress has been shown to play an important role in the development of anaemia in malaria. Indeed, increase in total antioxidant status has been shown to be important in recovery from malaria. The antioxidant activities of four medicinal plants traditionally used in the treatment of malaria in southwestern Nigeria were determined.
Methods: The ethanolic extracts of the leaves of Carica papaya Linn. [Caricaceae] , stem bark of Magnifera indica Linn. [Anacardiaceae], leaves of Psidium guajava Linn. [Myrtaceae] and the leaves of Vernonia amygdalina Del. [Compositae], were used in the present study. The plant parts commonly used in the locality in malaria therapy were employed in this study. The plants were screened for the presence of phytochemicals and, their effect on 2,2-Diphenyl-1-picryl-hydrazyl radical (DPPH) was used to determine their free radical scavenging activity.
Results: Phytochemical screening of the plants showed the presence of flavonoids, terpenoids, saponins, tannins and reducing sugars. M. indica did not contain cardiac glycosides and alkaloids while, P. guajava also showed the absence of alkaloids and anthraquinones. Anthraquinones was similarly absent from V. amygdalina. Concentrations of the plant extracts required for 50% inhibition of DPPH radical scavenging effect (IC50) were recorded as 0.04 mg/ml, 0.313 mg/ml, 0.58 mg/ml, 2.30 mg/ml and 0.054 mg/ml for P. guajava, M. Indica, C. papaya, V. amygdalina and Vitamin C, respectively.
Conclusion: All the plants showed potent inhibition of DPPH radical scavenging activity, P. guajava being the most potent. The free radical scavenging (antioxidant) activities of these plants probably contribute to the effectiveness of the above plants in malaria therapy.
Keywords: Carica papaya, Magnifera indica, Psidium guajava, Vernonia amygdalina, Antioxidants, Malaria, DPPH, Oxidative stress.