Influence of Dietary Phytol, Isophytol, and Squalene on the Tocopherol Content of Liver Tissue

Abstract

Phytol, isophytol, and squalene were fed to 18-day-old vitamin E-depleted chicks for either 48 or 72 hours at levels ranging up to 1% of the diet, and the effect of these compounds on the absorption of d, α-tocopherol was examined. No appreciable effect was noted on the tocopherol content of liver tissue when phytol was fed at levels of 0.01, 0.04, 0.125, 0.16, and 0.25% of the diet. However, at 0.50 and 1.0% of the diet, approximately a twofold and a threefold increase, respectively, was observed. Isophytol had the opposite effect, showing approximately a 40% decrease in the liver tocopherol values. Squalene also had an adverse effect, but not to the same extent as did isophytol. An anomalous situation occurred with plasma tocophcrols and phytol intake. Increasing levels of phytol resulted in decreases in plasma tocopherol concentrations for both the tocopherol-supplemented and non-supplemented diets. Liver tissue was practically devoid of tocopherol when vitamin A acetate was fed at a level of 0.16% of the diet. When the level was increased to 0.48%, the birds failed to consume a sufficient amount of the diet to give meaningful data.