[Development of liposomal form of polyunsaturated fatty acid concentrate: ways of using in production of functional foods].

The research is aimed at obtaining a concentrate of polyunsaturated fatty acids (PUFA) in liposomal form and developing possible ways of PUFA application in manufacturing functional food products. The PUFA concentrate was obtained from the fat of the Baikal seal by method of complexing with urea. We prepared a liposomal form of PUFA concentrate by evaporating organic solvent from the solution of lipids to form a thin lipid film with addition of buffer solution and further extrusion of the obtained emulsion. We defined the size of liposomal particles by method of turbidimetry. We identified the fatty acid composition of the samples by gas-liquid chromatography using a chromatographymass spectrometer. Biomedical research was conducted on 30 adult male Wistar rats with initial weight of 130-150 g. We induced atherogenic experimental hyperlipemia in rats by adding 5% cholesterol, 0.3% of 6-methyl-2-thiouracil, 1% cholic acid and 5% of lard to their normal diet for 21 days. We used an automatic biochemical analyzer to define total cholesterol (TC), triglycerides (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoproteins (VLDL) in blood serum. As a result of the experiment, we obtained a concentrate from the seal fat with content of essential PUFA 12.2% of total fatty acids in which the ratio of ω-6:ω-3 was 1.3:1. We obtained the liposomal form of the PUFA concentrate, with the average size of the liposomes ranging from 144 to 158 nm. We have established that the blood serum of the animals with induced hyperlipidemia, which orally took the liposomal form of PUFA concentrate for 14 days in a dose of 20 mg/kg body weight, showed the decrease of total cholesterol content of LDL and VLDL, while HDL increased to the parameters in intact animals. This indicated a normalization of the lipid profile in rats and the lipid-lowering effect of the concentrate. Also, we have studied the possibility of enriching wheat bread with essential fatty acids by replacing some part of the water with the liposomal form of PUFA concentrate. The use of this additive increased the output volume of bread by 14%, intensified the crust color and didn't affect the organoleptic indicators of bread quality. Fatty acid analysis of the lipids in bread showed that after adding 3 g of PUFA concentrate in liposome form per 100 g of flour increased the content of ω-3 PUFA by 3.2 fold (191 mg per 100 g of bread), with the ratio of ω-6:ω-3 PUFA being 5.8:1. Thus, bread enriched with PUFA concentrate in liposome form can be positioned as a functional food product that contains ω-3 PUFA in an amount of 19.1% of the recommended daily intake in 100 g of final product and also as a product with optimal PUFA ratio of ω-6:ω-3.