Vitamin E consists of a mixture of tocopherols and tocotrienols (Fig. 18.1), and all are derivatives of 6-chromanol with an aliphatic side chain. The four tocopherol
Fig. 18.1 Tocopherol and tocotrienol structures homologs (a-, P-, y-, and 5-) have a fully saturated C16 phytol side chain , whereas tocotrienols (a-, P-, y-, and 5-) have a similar isoprenoid chain containing three double bonds . Individual tocopherols are named according to the position and number of the methyl groups on the phenol ring, with the a-, P-, y-, and 5-tocopherols containing three, two, two, and one methyl groups, respectively. These structural differences determine biological activity, a-homologues being the most biologically active. a-Tocopherol predominates in leaves of higher plants, whereas y-tocopherol is often the major form in seeds .
Was this article helpful?
Do You Suffer From the Itching and Scaling of Psoriasis? Or the Chronic Agony of Psoriatic Arthritis? If so you are not ALONE! A whopping three percent of the world’s populations suffer from either condition! An incredible 56 million working hours are lost every year by psoriasis sufferers according to the National Psoriasis Foundation.