Antioxidant activities of cultivated and wild Korean ginseng leaves

Cultivated and wild ginseng leaves were examined for their various antioxidant activities. Both ginseng leaves were extracted with methanol and sequentially partitioned with solvents in an order of increasing polarity. Among various solvent extracts in cultivated and wild ginseng leaves, EtOAC extracts in both ginseng leaves showed the most powerful scavenging activities against DPPH radicals. Data on other antioxidant activities, measured by inhibition rates against lipid peroxidation and linoleate oxidation, revealed similar results, showing the highest activities in EtOAC extracts, followed by butanol, water, chloroform and hexane extracts, in both cultivated and wild ginseng leaves. EtOAC extracts of wild ginseng leaves contained more phenolics (9.71 g:4.87 g/100 g, dry basis) and flavonoids (3.03 g:2.34 g/100 g, dry basis) than cultivated ginseng leaves. When EtOAC extracts were acid-hydrolyzed, two aglycones of flavonoids, quercetin (0.43 and 0.66 g/100 g, dry basis) and kaempferol (1.23 and 1.50 g/100 g, dry basis) were detected in cultivated and wild ginseng leaves. These differences in concentrations of key antioxidants between two different ginseng leaves seemed to be responsible for their differences in antioxidant activities.