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Products of ginseng browning reaction were investigated to determine the nature of their antioxidant activity using a model system, White Ginseng and Red Ginseng extracts. In the simulated ginseng model system, the brown color was intensified with an increase in the length of reaction time and tile antioxidant activity initially increased in proportion the length of reaction time for up to 17hrs and then leveled off thereafter. Parallel results were obtained manufacturing of Red Ginseng, Comparison of the antioxidant activity of the inner and outer solutions after dialysis of browning solution showed that the outer solution had a stronger antioxidant activity than the inner one. For further analyses, browning reaction products were fractionated into three peaks on Amberlite CG-120 type Ⅰ ionexchange resin and designated as fractions Ⅰ, Ⅱ and Ⅲ in order of elution. Partial characterization of the fractions revealed that floe most intense brown fraction (Fraction Ⅱ) had the strongest antioxidant activity and also exhibited reducing power for Somogyi-Nelson reagents and ninhydrin positive reaction. Both the browning reaction products and Red Ginseng extracts were found to possess potent reactivity with α,α´-diphenyl-β-picrylhydrazyl, whereas White Ginseng extracts showed negligible reactivity.
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