Tocotrienols—Variations on the Vitamin E Story

It seems only yesterday that my friends Gladys Emerson and her husband, Herbert, were part of the team at UC Berkeley that isolated and named a new group of compounds commonly known as tocopherols or simply vitamin E (Evans et al. 1936). Nearly three decades later, the unsaturated analogues of tocopherols, named tocotrienols, were isolated from the rubber plant (Bunyan et al. 1961). Tocotrienols, mostly found in dry annatto seed (~1,400 ppm), barley germ (~910 ppm), palm oil (~730 ppm), rice bra…