Evaluation, in an animal model study, of the effect of diet composition change and diet supplementation with b-group vitamins on the liver fatty acid profile

Introduction. Contemporary diet of men is characterised by a signifi cant contribution of processed and puri- fi ed products impoverished by technological processing in, e.g., B-group vitamins taking part in the synthesis of fatty acids. One of the means to prevent their insuffi cient intake is supplementation of food products with those components. Hence, an animal model study was undertaken in order to determine whether modifi cation of diet composition in which whole-grain components (whole grains of wheat and maize) are isocalorically substituted with white fl our and saccharose, and its complementary supplementation with B-group vitamins may trigger changes in the profi le of fatty acids synthesized in liver of rats. Material and methods. The study was conducted on 30 male rats aged 5 months. Group I was receiving the basal feed mixture (Labofed B), which contained among other things whole grains of wheat and maize. Groups II-III, in free access, were administered modifi ed feed mixture in which 83.5% of wheat present in the basal diet was substituted with wheat fl our, and 50% of maize - with saccharose. Contents of vitamin B 1 , B 2 , B 6 and PP and basic chemical composition in the feed mixture are determined by HPLC method and the fatty acid profi le with the modifi ed Folch method using gas chromatography. Groups I and II were receiving water to drink, whereas the animals from group III were administered 25 ml of an aqueous solution of vitamins in the following doses: B 1 - 0.94 mg, B 2 - 0.48 mg, B 6 - 0.5 mg, PP - 1.9 mg. In group III - to supplement differ- ences in contents of those vitamins between feed mixtures resulting from the exchange of components, which to some extent simulated the mode of supplementation in humans. Concentration of glucose was determined in blood serum and the amount of fat was determined with Soxhlet method in the dissected animals liver and the fatty acid profi le with the modifi ed Folch method using gas chromatography. Results. While analysing the achieved results it was stated that the animals, despite comparable quantities of ingested feed, differed in their body weight gains reached in the course of the experiment. In contrast, both the liver mass and its fat content did not differ signifi cantly between the analysed groups of animals. Further- more, livers of the animals fed the modifi ed diet were characterised by a decreased sum of monoenoic fatty acids and an increased sum of polyenoic fatty acids, compared to the animals receiving the basal diet. The fatty acid composition determined in livers of the animals fed the modifi ed diet and supplemented with B 1 , B 2 , B 6 and PP vitamins did not differ signifi cantly from that assayed in livers of the rats fed the modifi ed diet. Conclusions. Modifi cation of diet composition, consisting of substituting whole grains of cereals with wheat fl our and saccharose, and its complementary supplementation with B-group vitamins caused signifi - cantly higher body weight gains of the examined animals. Modifi cation of diet composition had a signifi - cant effect on a decreased level of monoenoic and an increased level of polyenoic fatty acids in rat livers.