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.