A STUDY TO DETERMINE THE PRESENCE OR NONPRESENCE OF CHOLESTEROL IN THE PLANT KINGDOM (STEROLS)

Cholesterol has been positively identified in the oils extracted from several plant seeds. The existence of cholesterol in the plant kingdom is significant because it has been one of the classic indexes for the differentiation of vegetable and animal oils. In this study, oil was extracted from sunflower chips, soybeans, cocoa beans, and two varieties of tobacco seeds. The oils were saponified and the unsaponifiables were extracted. Preparative thin-layer chromatography was used to separate total sterols from other lipid components. The sterols were then analyzed by analytical gas-liquid chromatography. Tobacco seed sterols were the richest source of the suspect compound studied. The tobacco seed sterol fraction obtained by preparative thin-layer chromatography was subjected to preparative gas-liquid chromatography to collect the compound with the retention time of cholesterol. The collected compound was verified to be (DELTA)('5)-cholesten-3 (beta)-ol (cholesterol). The supporting data were obtained using ('13)C-nuclear magnetic resonance spectrometry, electron-ionization mass spectrometry, mass-analyzed ion kinetic spectrometry, infrared spectrometry, melting point, digitonin precipitation, and analytical gas chromatography. The cholesterol content of the samples was found to be in the following ranges: (1) 67-137 mg per 100 g of oil for tobacco seeds; (2) 3.7-4.9 mg per 100 g for cocoa bean oil; and (3) less than 1 mg per 100 g for soybean and sunflower seed oils.