In vitro free radical scavenging potential of Cleome gynandra (ejobyo)
Abstract
A study was carried out to establish the antioxidant potential of Cleome gynandra (ejobyo),
specifically in the organic and aqueous extracts. The Cleome gynandra was obtained from the
nearby Kalerwe market, washed clean with distilled water and then grounded for extraction. The
extraction procedure used alcohol and distilled water for the organic and aqueous extracts
respectively. The extracts were left to stand for 3 hours at room temperature, with regular shaking
for the alcohol extract and occasional shaking for the aqueous extract. The end products were then
centrifuged at 4000 r.p.m for 20 minutes and the supernatant filtered off, in order to effectively
separate the final clear extract necessary for further analysis from the debris released during the
extraction process. This final extract was then treated with DPPH- methanol solution, whose loss
in original color and decrease in absorbance on addition of plant extracts was an indicator of the
antioxidant potential of C. gynandra. On addition of the aqueous extract, the DPPH-methanol
solution turned yellow, and on addition of the alcohol extract, it turned to an almost clear solution,
indicating massive loss of the original color. The absorbance decreased from 0.5 in the original
DPPH-methanol solution (control) to 0.3975 (mean value) and 0.0475 (mean value) on addition
of the aqueous and alcohol extracts, respectively. This resulted into a free radical scavenging
potential of 20.5% and 90.5% for the aqueous and alcohol extracts, respectively. The alcohol
extract, therefore, had a 70% (about 4.4 times) more free radical scavenging potential than the
aqueous extract, and therefore, more antioxidant potential than the aqueous extract.