Research Article
Evaluation of the In Vitro and In Vivo Antioxidant Potentials
of Aframomum melegueta Methanolic Seed Extract
Samuel Okwudili Onoja,
1
Yusuf Ndukaku Omeh,
2
Maxwell Ikechukwu Ezeja,
1
and Martins Ndubuisi Chukwu
2
1
Department of Veterinary Physiology, Pharmacology, Biochemistry and Animal Health and Production,
College of Veterinary Medicine, Micheal Okpara University of Agriculture, PMB 7267, Umudike, Nigeria
2
Department of Biochemistry, College of Natural Sciences, Micheal Okpara University of Agriculture, PMB 7267, Umudike, Nigeria
Correspondence should be addressed to Samuel Okwudili Onoja; samonreal@yahoo.com
Received 22 February 2014; Revised 1 May 2014; Accepted 4 May 2014; Published 15 May 2014
Academic Editor: Shyam Sundar
Copyright © 2014 Samuel Okwudili Onoja et al. Tis is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Aframomum melegueta Schum (Zingiberaceae) is a perennial herb widely cultivated for its valuable seeds in the tropical region
of Africa. Te present study evaluated the antioxidant efects of methanolic seed extract of A. melegueta. Te antioxidant efects
were evaluated using in vitro, 2, 2-diphenylpicrylhydrazine photometric assay and in vivo serum catalase, superoxide dismutase and
thiobarbituric acid reactive substance assay method. Te extract (25–400 g/mL concentration) produced concentration dependent
increase in antioxidant activity in 2, 2-diphenylpicrylhydrazine photometric assay. Te extract (400mg/kg) showed a signifcant
( < 0.05) increase in serum catalase and superoxide dismutase activity when compared with the control group. Te extract
(400 mg/kg) showed a signifcant ( < 0.05) decrease in the serum level of thiobarbituric acid reactive substance when compared
with the control group. Tese fndings suggest that the seed of A. melegueta has potent antioxidant activity which may be responsible
for some of its reported pharmacological activities and can be used as antioxidant supplement.
1. Introduction
Antioxidants act as a defence mechanism that protect against
deleterious efects of oxidative reaction produced by reactive
oxygen species (ROS) in a biological system [1]. Reactive
oxygen species not only are produced naturally in cell
following stress or respiration but also have been reported
to be produced by radiation, bacterial and viral toxin,
smoking, alcohol, and psychological or emotional stress.
Overproduction of ROS and/or inadequate antioxidants has
been implicated in the pathogenesis and complications of
some disease conditions like diabetes, Alzheimer’s disease,
cancer, atherosclerosis, arthritis, neurodegenerative disease,
and aging process [2, 3]. Antioxidants have been reported to
prevent oxidative damage caused by ROS by reacting with
free radicals, chelating, and catalytic metals and also by acting
as oxygen scavengers [4, 5]. Te antioxidants in biological
system can be either enzymatic or nonenzymatic. Te enzy-
matic antioxidants include catalase, superoxide dismutase,
and glutathione which catalyse neutralization of many types
of free radicals [6], while the nonenzymatic antioxidants
include Vitamin C, selenium, vitamin E, carotenoids, and
polyphenols. Tere is growing evidence that antioxidants
play a pivotal role in the prevention of heart disease, cancer,
DNA degeneration, pulmonary disease, and neurological
disorder [7]. Recently, there has been an upsurge of interest
in the therapeutic potential of plants as antioxidants in
reducing oxidative tissue injuries [3]. Plants, herbs, and
spice, rich in phenolic compounds like favonoids, have
been demonstrated to have anti-infammatory, antiallergenic,
antiviral, antiaging, and anticarcinogenic activities which can
be attributed to their antioxidant properties [7, 8].
Aframomum melegueta Schum (Zingiberaceae) also
known as Guinea pepper, grains of paradise, or alligator
pepper (indigenous names include Atare in Yoruba, Ose-oji
in Igbo, and Citta in Hausa) is a perennial herb widely
cultivated for its valuable seeds in the tropical region of
Africa [9, 10]. It grows up to 1.5m in height, with purple
Hindawi Publishing Corporation
Journal of Tropical Medicine
Volume 2014, Article ID 159343, 6 pages
http://dx.doi.org/10.1155/2014/159343