The Siberian Larch Needle Group Composition and Acids at Various Vegetation Periods

摘要

The research results of the Siberian larch needle extractives are presented in paper. The content of extractive substances from green and yellow needles extracted by organic solvents with different polarities is determined. It is found out that the double increase of the yellow needle extractive substances content soluble in hydrocarbon extractant is observed, whereas it is decreased by 30%, when extracted with propan-2-ol. The group composition of needle extracts derived from isopropanol extract by petroleum ether is determined. The neutral substances content in both needle collections is practically the same, although the yellow needles contain less "bound" acids in the form of esters. High wax content is noted in the needles, which mainly consist of secondary nonacosanol-10 alcohol. The composition of free and "bound" acids in Siberian larch needles at various vegetation periods is established. The groups of higher unsaturated C18 fatty acids prevail in the needles. The resin acids are represented by isopimaric acids (isopimaric and sandaracopimaric) and abietic acids: abietic, dehydroabietic and levopiric acids. The dehydroabietic acid content is increased quadrupled in yellow needles and the hydroxy acids are identified: 15-hydroxyabietic acid and 15-hydroxyhydroabietic acids. The tri- and tetraenic C20 acids are identified among higher fatty acids.