Abstract

ANTIOXIDANT CAPACITY AND DNA DAMAGE PROTECTIVE ACTIVITY OF THE ROOT EXTRACT OF NAUCLEA LATIFOLIA

*Ottah C. U., Etuk E. U., Bello S. O., Bilbis L. S., Ndodo N. D. and Ottah V. E.

Abstract

Damage to the genome caused by free-radicals is fundamental to the genesis of genetic diseases. Plants are rich in phytochemicals including tannin, saponin, flavanoids, alkaloids and phenolics, with a variety of metabolic activities, which includes antioxidant potential. Nauclea latifolia is used by traditional herbal medicine practitioners to treat many common illnesses including chronic diseases in Northwest Nigeria Phytochemical screening and antoxidant studies were carried out on the root extract of Nauclea latifolia. The phytochemical studies was done following standard procedures. Antioxidant activity of Nauclea latifolia extract was studied by mixing 0.03mM solution of DPPH radical (1, 1-diphenyl-2-picryl hydrazyl) with different concentrations (100, 50, 25, 10,5 and 2.5μgml-1) of the extract. The DNA nicking assay using fenton’s reagent was also carried out to ascertain the DNA damage protective activity of the N. latifolia root extract. This was done using supercoiled pBR322 plasmid DNA and different concentrations (100 μg/ml and 200 μg/ml) of the extract. The phytochemical studies revealed the presence of bioactive plant metabolites; tannins, flavonoids, alkaloids, saponins, anthraquinones, carbohydrates, phytosteroids and diterpene. Antiradical activity of the root extract of N. latifolia using DPPH (1, 1-diphenyl-2-picryl hydrazyll) showed that the root extract of N. latifolia inhibited the DPPH free radical dose dependently. The DNA nicking assay showed ability of the extract to protect the integrity of plasmid DNA pB322 from the deleterious effect of hydroxyl radical generated by fenton’s reaction in same manner as standard antioxidant, l-ascobic acid. Nauclea latifolia extract demonstrated antioxidant activities, ability to scavenge-free radicals and protects the integrity of DNA.

Keywords: Antioxidant activity; DNA nicking; Nauclea latifolia; Radicals.