Composition of fatty acids of higher aquatic plants in Lake Kotokel as valuable biological raw materials

Fatty acids, as part of cell membranes, determine their fluidity and dielectric constant. In addition, they play an important role in human and animal nutrition. This work examines the composition and fatty acid content of dried higher aquatic plants from Lake Kotokel (Republic of Buryatia, Russia) and their potential as a raw material for the production of feed and biologically active food supplements. A modified Bligh-Dyer method was used to extract lipid fraction. Fatty acids in the form of their methyl esters were analysed by gas chromatography–mass spectrometry. Palmitic C16:0 acid was the main saturated fatty acid found in Myriophyllum sibiricum, Elodea canadensis, Persicaria amphibia and Potamogeton perfoliatus in Lake Kotokel. The main unsaturated acid found in plants, regardless of their type, was the α-linolenic C18:3-ω3 acid. In addition, a relatively high content of stearic C18:0, myristic C14:0 and pentadecanoic C15:0 acids was noted. Branched acids (i-C14:0, i-C15:0, i-C16:0, i-C17:0, i-C20:0, a/i-C15:0, a/i-C17:0 and 10Me-C16:0) and odd carbon numbered acids (C13:0, C15:0, C17:0, C19:0, C21:0 and C23:0) were identified. An analysis of the authors’ and literature data revealed that the studied species of higher aquatic plants in reservoirs in the Asian part of Russia are characterised by a high content of α-linolenic C18:3-ω3 (up to 56%) and a low content of oleic C18:1-ω9 (up to 1.81%) acids. The content of α-linolenic C18:3-ω3 acid in plants from reservoirs in the European part of Russia was lower (up to 42%), while that of oleic acid C18:1-ω9 was higher (up to 14%).