Functional and chemical stability of a medicinal herb, Artemisia capillaris, following gamma sterilization

The stability of functional and chemical properties of gamma-irradiated (10 kGy) Artemisia capillaris, a widely used herb in the traditional Oriental medicine, was investigated. Functional properties of the extracts of gamma-irradiated and non-irradiated A. capillaris were compared in antioxidant activities, such as 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical and superoxide anion radical scavenging, lipid peroxidation inhibition, and protection of lymphocyte and plasmid DNA. Their chemical properties were assessed by HPLC analysis, comparing with chlorogenic acid and caffeic acid, which were isolated from ethylacetate fraction as major compounds with strong antioxidant activities. No significant difference in functional properties between irradiated and non-irradiated A. capillaris was found in all antioxidant assays. Also HPLC analysis of ethyl acetate fractions of irradiated and non-irradiated A. capillaris revealed the preservation of chlorogenic acid (_tR=3.124 min) and caffeic acid (_tR=3.672 min), and showed almost the same pattern in the general peaks. These results suggest that the chemical components and antioxidant properties of A. capillaris are not affected largely by gamma-ray irradiation. Therefore, this study may provide evidence that the irradiated herbs retain their potential functional properties