Identification and estimation of tocotrienols in the annatto lipid fraction by gas chromatography‐mass spectrometry

Abstract

Abstract The lipid fraction of annatto ( Bixa orellana L.) seeds was extracted with a Soxhlet apparatus with n ‐hexane and isolated by thin‐layer chromatography. The fatty‐soluble antioxidant fraction contained only tocotrienols, mainly δ‐tocotrienol, but no tocopherols. The presence of tocotrienols was confirmed by gas chromatography‐mass spectrometry. The quantities of δ‐tocotrienol were 140–147 mg/100 g dry seeds and 5.2–5.5% wt/wt of lipid extract, determined by gas chromatography and high‐performance liquid chromatography, respectively. Currently no vegetable species seems to contain comparable concentrations of δ‐tocotrienol.