동부를 80% MeOH로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 $H_2O$로 용매 분획 하였다. 이 중 EtOAc과 n-BuOH 분획으로부터 silica gel과 octadecyl silica gel(ODS) column chromatography를 반복하여 4종의 sterol 화합물을 분리, 정제하였다. 각 화합물의 화학구조는 NMR, MS 및 IR 등의 spectrum data를 해석하여, stigmasterol(1a), $eta$-sitosterol(1b), 7-ketositosterol(2) 및 stigmasterol 3-O-$eta$-D-glucopyranoside(3)로 동정하였다. 화합물 1b, 2와 3은 동부에서 처음 분리되었다.
The seed of cowpea (Vigna sinensis K.) was extracted with 80% aqueous methanol (MeOH). And the concentrated extract was partitioned with ethyl acetate (EtOAc), n-butanol (n-BuOH) and $H_2O$, successively. The repeated silica gel and octadecyl silica gel (ODS) column chromatographic separations for the EtOAc and n-BuOH fractions led to isolation of four sterols. And the chemical structures of the compounds were determined as a mixture of stigmasterol and $eta$-sitosterol with the ratio of 4 to 3 (1), 7-ketositosterol (2), and stigmasterol 3-O-$eta$D-glucopyranoside (3) from the interpretation of spectroscopic data including nuclear magnetic resonance (NMR) spectrum metric, mass (MS) spectrum metric and infrared (IR) spectroscope. This study reports the first isolation of $eta$-sitosterol, 7-ketositosterol, and stigmasterol 3-O-$eta$-D-glucopyranoside from the seed of Vigna sinensis K. In addition, compound 2, 7-ketositosterol, is rarely occurred in natural source including plant.
