In 1922, embryologist H M Evans discovered tocopherols (TP) which are needed for human reproduction (Evans and Bishop, 1922; Evans et al., 1974). More than 40 years later, the isolation of tocotrienol (T3) from latex was first reported by R A Morton (Danphy et al., 1965). To date, vitamin E consists of T3 and TP. Together with TP, T3 provides a significant source of anti oxidant activity in all living cells. This common anti oxidant attribute reflects the similarity in chemical structure between T3 and TP, which differ only in their structural side-chain (T3 contains farnesyl while TP has a saturated phytyl side-chain). The common hydrogen atom from the hydroxyl (OH) group on the chromanol ring acts by scavenging the chain-propagating peroxyl free radicals. Depending on the location of the methyl groups on their chromanol ring, T3 and TP can be distinguished as four isomeric forms: alpha (a), beta (b), gamma (g), and delta (d). As TP was discovered much earlier compared to T3, TP has been more widely applied in human nutrition.
