Abstract
Paulownia coreana Uyeki fruits were collected, extracted with acetone-$H_2O$ (7:3, v /v), fractionated with n-hexane, methylene chloride, and ethyl acetate, then freeze dried to give some dark brown powder. The ethyl acetate soluble mixture was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. Spectrometric analysis such as NMR and MS including TLC were performed to establish the structures of the isolated compounds. From the ethyl acetate fraction, one phenolic acid (I) and five flavonoids (II~VI) and were isolated and elucidated. The antioxidative activities were tested on the isolated compounds, crude and fractionated extractives by DPPH radical scavenging method. The result showed that caffeic acid, kaempferol, luteolin, quercetin and the EtOAc soluble fraction exhibited higher activities than those of ${\alpha}$-tocopherol and BHT.
오동나무 열매를 채취하여 건조시킨 후 분말로 제조하여 5.0 kg을 아세톤-물 (7:3, v/v) 혼합용액으로 추출하고 유기용매를 제거한 후 헥산, 메틸렌클로라이드, 에틸아세테이트 및 물 등 네 개의 분획으로 분리하여 에틸아세테이트용성 분획물을 Sephadex LH- 20으로 칼럼 크로마토그래피를 수행하였으며 용리용매는 메탄올 수용액과 에탄올-헥산 혼합액을 사용하였다. 그 결과 phenolic acid 화합물인 caffeic acid와 flavonoid 화합물인 naringenin, kaempferol, apigenin, luteolin 및 quercetin이 단리 되었으며 NMR 및 MS 스펙트럼을 이용하여 구조를 결정하였다. 각 분획물과 단리 된 화합물들 그리고 조추출물은 DPPH radical 소거법을 이용하여 항산화 실험을 실시하였으며, 분획물중에는 에틸아세테이트용성이 그리고 화합물중에는 caffeic acid, kaempferol luteolin 및 quercetin이 우수한 항산화 효능을 나타내었다.