Superoxide Radical Scavenging Properties of Extracts and Flavonoids Isolated from the Leaves of Blumea balsamifera

Abstract

In view of the pharmacological interest in flavonoids, the superoxide radical scavenging capacity of pet-ether, chloroform, and methanol extracts and flavonoids of Blumea balsamifera DC leaves on nonenzymatically (phenazine methosulfate/NADH) generated superoxide radicals were evaluated. The methanol extract (93.91 ± 1.37%) exhibited higher radical scavenging activity than the chloroform extract (84.58 ± 1.51%). The pet-ether extract was inactive toward nonenzymatically generated superoxide radicals. The superoxide radical scavenging capacity of flavonoids (100 µM) as determined was decreased in the order quercetin > luteolin > 5,7,3′,5′-tetrahydroxyflavanone > blumeatin > rhamnetin > tamarixetin > luteolin-7-methyl ether > dihydroquercetin-4′-methyl ether > dihydroquercetin-4′,7-dimethyl ether. It was concluded that flavonoids with a free hydroxyl group were more active than methylated compounds, and the flavonoid content of extracts contributed to their superoxide radical scavenging activity.

Keywords: :

• Blumea balsamifera
• flavonoids
• leaf extracts
• superoxide radical scavenging activity