ABSTRACT
The term “vitamin E” is used as the collective name for eight naturally occurring molecules (δ-, α-, β-, and γ-tocopherols and tocotrienols) which qualitatively showed the biological activity of tocopherol. Tocotrienols differ from tocopherols in their hydrocarbon tail; tocotrienols have an unsaturated isoprenoid tail while tocopherols have a saturated one. In this chapter, the term “tocotrienol-rich vitamin E (TRE)” indicates vitamin E preparations where the predominant vitamin E in the preparation is tocotrienols. This term is used, as almost all the available marketed tocotrienol preparations and natural tocotrienols exist together with tocopherols (Rasool and Wong 2007). For example, between 70% and 80% of vitamin E obtained from palm oil consists of a mixture of the different tocotrienol isomers while the rest are tocopherols.
