Abstract: In this study,the extraction process of total sterol from seed kernel oil of Xanthoceras sorbifolia bunge were studied using saponification method.The chemical components of extract were analyzed using gas chromatography-mass spectrometry (GC-MS) after purification.Through single factor and orthogonal experiments,the effects of saponification time and temperature,liquid/solid ratio,ethyl acetate dosage on the total sterol content were investigated.The results showed the optimal extraction conditions of sterol were as follows:ethyl acetate dosage of 200 mL,solid-liquid ratio of 1:5 (g/mL),saponification temperature of 67 ℃ for 120 min.Using these conditions,the total content of sterol got the highest ratio of 0.498%.After purification of coarse sterol with solvent crystallization method,the GCMS analysis showed that five monomers were detected in total sterol,namely stigmast-5,12dien-3-ol,stigmasta-7,22-dien-3-ol,ergosta-7,22-dien-3-one,β-sitosterol and 33-norgorgosta-5,24(28)-dien-3-ol.This result will provide the basis for the further studying the function of seed kernel sterol of X.sorbifolia.

Key words: seed kernel oil of Xanthoceras sorbifolia bunge, total sterol, saponification, extraction, anelysis