Isolation and quantitative analysis of peroxynitrite scavengers from <Emphasis Type="Italic">Artemisia princeps</Emphasis> var. <Emphasis Type="Italic">orientalis</Emphasis>

Young and mature Artemisia princeps var. orientalis (APO, Compositae) are used as a health food and a medicinal plant, respectively, in Korea. Here, we identified the in vitro potent peroxynitrite (ONOO⁻)-scavenging effect (IC₅₀, 0.26 μg/mL) of the components from the EtOAc fraction. Octadecylsilane column chromatography on the EtOAc fraction yielded two caffeoylquinic acid compounds, 3,5-di-O-caffeoyl-muco-quinic acid (1) and methyl 4,5-di-O-caffeoylquinate (2) by NMR spectroscopic data, which have not been reported before from APO. The IC₅₀ values of compounds 1 and 2 were 0.18 ± 0.01 μg/mL and 0.12 ± 0.00 μg/mL, respectively, lower than that of the positive control (L-penicillamine). HPLC data indicated that young APO (1: 30.3 mg/g dried weight, 2: 27.7 mg/g) contained considerably higher quantities of the two caffeoylquinic acids than mature APO (1: 1.77 mg/g dried weight, 2: 4.10 mg/g).