Annales de la nutrition et de l'alimentation最新文献

A perceptible increase in the grade of nitrates in drinking waters in the Yonne Country had been established from 1969 to 1975 and had formed the subject of a previous published work. The present issue gives details about the persuit of this research from 1975 to 1979. It appears from it that the increase in the grade of nitrates in drinking waters is definitely continuing in most areas from 1975 with the exception of Morvan and Senonais. In 1979, the highest average grades reached 37 mg NO3/1 (Plateaux de Bourgogne) and the lowest 7 mg NO3/1 (Morvan). The number of collectings where the grades exceeded 44 mg/1 is increasing: 8% in 1975, 21% in 1979.

In man as in animals, the intake of long chain saturated fatty acids (14:0, 16:0, 18:0) representing 95% of the human diet saturated fatty acids, induce a similar increase in platelet functions (coagulation and aggregation to thrombin) to this found in coronary patients or subjects highly susceptible to coronary disease. These platelet function abnormalities resemble those observed in essential fatty acids deficient animals both being characterized, in the platelet phospholipids, by an increase in 18:1 and 20:3 omega 9, at the expense of the fatty acids from the omega 6 series. The platelet function and composition changes can be reversed by increasing the dietary intake of 18:2, a specific effect (at least for polyunsaturated fatty acids) since it cannot be reproduced by a monoeme such as oleic acid.

The incorporation of dietary trans fatty acids is shown into intestinal brush border and heart mitochondrial membranes obtained from rats fed with either partially hydrogenated soybean oil or with a synthetic triglyceride containing elaidic or linelaidic acid. The distribution of dietary linelaidate in the major phospholipid classes from inner membranes of mitochondria is determined. Heart mitochondria from normal rats and linelaidic acid fed rats are compared with respect to their swelling rate and their oxidative phosphorylation. The influence of dietary linelaidate on the activity of some brush border-associated enzymes is also studied. On the basis of the authors' observations and those made by others with microorganism cels or models of biological membranes (liposomes and monomolecular films), the possible implications of trans fatty acids incorporation on membrane functions are reviewed.

Digestibilities of cis and trans docosenoic acids (C 22:11) have been determined in male growing Wistar rats. Eight groups of rats were fed diets with 0.04 or 0.92% calcium and 15% lipids; the latter contained about 46% cis or trans C:22:1, and 1.5 or 28% linoleic acid. Food consumption was recorded and faeces were collected during 9 days. Fecal lipids were extracted in two fractions: soluble (in chloroform), and insoluble; the fatty acids of both fractions were analysed by gas-liquid chromatography. Calcium and, in some cases, Phosphorus, were determined in the soluble fraction. The digestibility of brassidic acid was strongly lowered by the presence of Calcium in the diet (-35 points). This was due to the massive formation, in the gut, of insoluble Calcium complexes (probably Calcium soaps) of brassidic acid. Dietary linoleic acid improves the absorption of brassidic acid (+ 17 points). This effect could result from the lower melting point of the dietary fat (37 degrees C instead of 48 degrees C) and/or from the emulsifying properties of monolinolein in the intestine. The effects of Calcium and of linoleic acid were additives. In the most favourable conditions (no Calcium, 28% linoleic acid), brassidic acid digestibility reached 98%. Erucic acid digestibility was decreased by dietary Calcium, but to a lesser extent than that of brassidic acid (-17 points). Here again, the formation in the gut of Calcium erucate and Calcium-Phosphorus-erucate complexes was responsible of this phenomenon. As a matter of fact, the digestibility of erucic acid reached nearly 100% when no Calcium was added to the diet. The absorption of erucic acid was not improved by dietary linoleic acid.