For thousands of years, nature has been a rich source of medicinal-derived diversities. A remarkable number of potent drugs have been isolated from natural sources, particularly plants, many of which are well established in their use in traditional medicine [1]. Plant extracts have shown to exhibit excellent inhibitory activities such as antimalarial, antibacterial, antifungal, anticancer, some of which may be related to their antioxidant property. Antioxidant-containing constituents of plants could act as hydrogen donor, electron donor, peroxide decomposer, singlet oxygen quencher, enzyme inhibitor or metal chelating agent. Antioxidants at low concentration significantly delays or prevents oxidation of the usual protein or lipid substrate [2]. Living cells generate free radicals and other reactive oxygen species as by-products of physiological and biochemical processes. These free radicals can cause oxidative damage to lipids, proteins and DNA, eventually leading to many chronic diseases, such as cancer [3]. Phyto-constituents such as vitamins, terpenoids, phenolic acids, tannins, flavonoids, quinones, coumarins, alkaloids, etc, possess free radical scavenging (antioxidant) activity [4].

Parinari curatellifolia (family: chrysobalanaceae) is a plant used in Nigerian folk medicine for treatment of cancer and other diseases. In our search for pharmacologically active compounds, we have isolated and characterized a series of compounds through column chromatography and spectroscopic techniques (MS, NMR and IR). We have evaluated the in vitro antioxidant activity of the different extracts and the pure compounds using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical model. The in vitro anticancer activity of the extracts and the pure compounds using the sodium 3’-[1-(phenylamino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitro] benzene sulfonic acid hydrate (XTT) colorimetric method on cervical cancer (HeLa) cell line have also been assessed. The extracts and pure compounds have displayed moderate to excellent antioxidant and anticancer activities. These suggest that these compounds may be suitable candidates for further drug development and investigation. The results obtained have provided some scientific basis for the use of P. curatellifolia in traditional medicine for treatment of cancer.

[1]     Gordon M.Cragg and David J. Newman, Pure Appl. Chem., 2005, 77 (11): 1923–1942

[2]     Halliwell b and Gutteridge JMC Claredon Press, Oxford ., 1989, Pp: 617 – 783.

[3]    Harman D: Ann NY Acad Sci, 1998, 854:1-7.

[4]    Zheng W, Wang SY. J Agric Food Chem., 2001,  49 (11) : 5165-5170.       

Date: Thursday, 13 December, 2012                                                

Time: 11:00 – 12:00

Venue: The Avogadro (3.22) – Chemistry Building

Contact Person: Dr Natasha October        [email protected]