The Effect of Dietary Citrus Pectin on Fatty Acid Balance and on the Fatty Acid Content of the Liver and Small Intestine in Rats

Abstract

The effect of 10% dietary citrus pectin on the fatty acid (FA) balance and on the FA contents of the liver, blood serum and small intestine in rats were investigated. The amount of food consumed and excreted feces was measured during 5 days in metabolic cages. The contents of FA in the food, feces, liver blood serum and small intestines were determined by gas chromatography. The pectin-fed rats (gr. [group] P) consumed less and excreted more total lipids and total FA than the controls (gr. K) in the feces. The excretion of saturated FA with longer chains increased in the gr. P (when compared with gr. K) more than those with the shorter chains: C18 > C17 > C16 > C15 > C14. The excretion of the more saturated FA increased more than the less saturated: C16:0 > C16:1; C17:0 > C17:1; C18:1 > C18:2. The dietary pectin modified the apparent FA absorption pattern. A part of the dietary FA (C18:3; C20:1; C20:4.omega.3; C20:5; C22:1; C22:5 and C22:6) was not found in the feces. These FA were mainly absorbed in the small intestine and deposited in tissues. In the feces 2 unidentified FA were found: X1 and X2 (presumably C14 and C15 with branched chains). They were not found in the liver or in the small intestines but occur in blood serum in small amounts. The content of C14, C17:1, C18:1 and C18:2 in the liver (expressed as % of total FA) was lower in gr. P, and that of C18, C20:3 and C20:4.omega.6 higher than in the controls. The volatile FA which originated from the pectin decomposition may cause the differences in the tissue content of FA.