Research of fatty and organic acids in Rhododendron luteum Sweet leaves

Abstract

Rhododendron luteum Sweet of the Heath family Ericaceae is found on the territory of Ukraine both in the wild and is widely cultivated in botanical gardens, parks, squares. Leaves and inflorescences are used to treat heart disease, rheumatism, gout, and disorders of the nervous system. The literature data on the chemical composition relate to the presence of aminoacids, organic acids, essential oils, phenolic and triterpene compounds, andromedol derivatives.
 The aim of the work was to determine the composition and content of fatty and organic acids in the Rhododendron luteum Sweet leaves by gas chromatography-mass spectrometry.
 The object of the study was the leaves of Rhododendron luteum Sweet, collected on the territory of the botanical garden of H. S. Skovoroda Kharkiv National Pedagogical University in 2019. Gas chromatography - mass spectrometric study of the component composition and content of fatty and organic acids in the leaves of the studied plant on an Agilent Technologies 6890 chromatograph with a 5973 mass spectrometric detector was carried out.
 In Rhododendron luteum Sweet leaves 37 substances were found and identified. Fatty acids were represented by 17 compounds. Among saturated fatty acids, palmitic acid (3 276.2 mg/kg) was prevailed, among monounsaturated – oleic (736.78 mg/kg), among polyunsaturated – linolenic (1 617.65 mg/kg). The smallest amounts contained heneukocylic (46.33 mg/kg), lauric (58.17 mg/kg) and caproic (68.17 mg/kg) acids, which belong to saturated fatty acids. The presence of 20 organic acids in the raw material was also established: citric (8 680.30 mg/kg) and iso-citric (4 106.85 mg/kg) acids dominated in terms of quantitative content; oxalic (1 685.65 mg/kg) and malic (1 310.82 mg/kg) acids were contained in significant amounts. Among the derivatives of hydroxybenzoic acid, the greatest amount was presented by gentisic (187.76 mg/kg) acid, among the derivatives of hydroxycinnamic acids – p-coumaric (312.62 mg/kg).
 For the first time, the qualitative composition and quantitative content of fatty and organic acids in Rhododendron luteum Sweet leaves was studied by gas chromatography with a mass spectrometric detector. The obtained results indicate the prospects for further study of raw materials to develop drugs with membrane stabilizing and anti-inflammatory activity.