Flavonoidal constituent in Korean Lactuca dentata Makino

한국산 씀바귀의 Flavonoid 성분에 관한 연구

The ethylacetate extract of Lactuca dentata Makino showed 6 flavonoidal components as detected by ferric chloride solution. The flavonoidal constituent of Lactuca dentata Makino was isolated and purified by the series of column chromatography. The chemical structure of one of the flavonoidal component named as compound E was identified by UV, IR and NMR spectrometry. The melting point range of compound E was $249.5^{\circ}C-251^{\circ}C$. The UV and IR spectra of purified compound E, and its genin were measured with the various shifting agents. The results of UV analysis showed the free state of hydroxy group at 3rd and 4th carbon and binding of sugar at the 7th carbon of compound. The sugar bound to the compound E was identified as glucose by TLC. The IR spectrum showed the presense of hydroxy group, conjugated carbonyl group and aromatic group. The analysis of NMR spectrum was done to the purified compound and its derivatives. The chemical shifts against hydrogen atom, hydroxy group, and the moiety of luteolin were observed in the NMR spectrum along with their position and number as well as type of sugar bound. The isolated and purified compound was identified as $luteolin-7-0-{\beta}-D-glucoside$.

한국산 씀바귀(Lactuca dentata Makino)의 ethylacetate 추출물에서 6 종류의 flavonoid 성분이 TLC에 의해서 검출 되었으며, 이들은 극성에 따라서 A에서 F가지 명명되었다. 그들 중 주성분으로 생각되는 물질 E를 column chromatography을 이용하여 분리정제 하였다. 물질 E의 녹는 점은 $249.5^{\circ}C-251^{\circ}C$ 로 나타났으며, 그 구조를 밝히기 위하여, 물질 E와 이를 가수분해한 genin에 대한 여러가지 shift reagent에서 UV와 IR분석을 하고 또한 물질 E와 그의 acetyl 유도체에 대한 NMR 분석을 하였으며 물질 E에 결합된 당은 TLC에 의하여 확인하였다. 이와같은 분석 결과에서 물질 E는 luteolin 모핵에 glucose가 결합된 $luteolin-7-0-{\beta}-D-glucoside$로서 확인되었다.