VALIDATED METHOD FOR QUANTITATION AND IDENTIFICATION OF 4,4-DESMETHYLSTEROLS AND TRITERPENE DIOLS IN PLANT OILS BY THIN-LAYER CHROMATOGRAPHY HIGH-RESOLUTION GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

Alkaline hydrolysis was performed on a series of different vegetable o ils. The unsaponifiable lipid matter was extracted with ethyl ether, a nd the class of 4,4-desmethylsterols (sterols) plus the triterpene dio ls (diols) erythrodiol, uvaol, and betulinol were isolated by thin-lay er chromatography. A validated method using the acetate derivatives of sterols instead of their silyl ethers is presented. The acetate deriv atives were analyzed by high resolution gas chromatography (HRGC), Ret ention time, precision, recovery studies, and absolute response factor s were calculated for these esters, and GC/mass spectrometric structur e of the assigned retention times was confirmed for the sterols and tr iterpene diols.