Comparison of Some In-vitro Antioxidant Properties of Cola acuminata and Cola nitida Fruit Testas

Abstract

Testas of Cola fruit are usually considered as agricultural waste by many farmers as their focus is always on the seed because of its economic importance. This study therefore aimed at evaluating and comparing the antioxidant potentials of C. acuminata and C. nitida fruit testas. The methanol extract of the fruit testas of C. acuminata and C. nitida were evaluated and compared for their antioxidant properties such as: their scavenging abilities on hydroxyl radicals, ABTS (2, 2– Azino-bis-3-ethylbenzothiazoline-6-sulphonic Acid), DPPH (2, 2-diphenyl-2-picrylhydrazyl) and nitric oxide. Also their ferric reducing ability and total antioxidant were investigated. In all the antioxidant parameters assayed, the fruit testas of C. acuminata and C. nitida compared favorably well with the standard (Butylated Hydroxytoluene) as they both showed positive correlation with the standard. The antioxidant ability of the methanol extract of C. nitida was significantly lower compared with that of C. acuminata in all the parameters tested. This can be attributed to the hydrogen atom donating potentials of the testas which can be as a result presence of vital secondary metabolites in therapeutic mopping up of free radicals in form of reactive oxygen species (ROS) and reactive nitrogen species (RNS).