The term vitamin E refers to a family of eight related, lipid-soluble, antioxidant compounds widely present in plants. The tocopherol and tocotrienol subfamilies are each composed of alpha, beta, gamma, and delta fractions having unique biological effects. Different ratios of these compounds are found in different parts of a plant. For example, the green parts of a plant contain mostly alpha tocopherol and the seed germ and bran contain mostly tocotrienols. Along with other nutrients, tocopherols and tocotrienols are concentrated in the bran layers of the rye grain, and are only present at low levels in the flour endosperm. Tocopherols are also present in algae, mint teas, and other foods.