Chemical composition of essential oils from flowers of veronica Longifolia L., Veronica Incana L. and Veronica Spicata L.

In the Ukrainian flora, species of Veronica L. genus (Plantaginaceae Juss.) are classified into 8 sections. The phytochemical research into secondary metabolites of Veronica L. genus most related to the study of phenolic compounds and iridoids, while terponoids of these species need further research. The chemical profiles of V. longifolia L., V. incana L. and V. spicata L. of Ukrainian flora are poorly studied. Phenolic acids, hydroxycinnamic acids, coumarins, flavonoids, tannins, iridoids, saponins, amino acids and organic acids have been reported for these species. Herbs harvested during the flowering stage are often used in the pharmaceutical industry, so the research into chemical composition of essential oils from Veronica species flowers are urgent. The aim of this study was a comparative GC/MS study of the chemical composition of essential oils from V. longifolia L., V. incana L. and V. spicata L. flowers of Ukrainian flora. Materials and methods. The objects of the research were flowers of Veronica spp. of Pseudolysimachium W.D.J. Koch section, namely V. longifolia L., V. incana L. and V. spicata L., harvested in the Botanical Garden of V. N. Karazin Kharkiv National University. The study of the chemical composition of essential oils was carried out by chromatography mass spectrometry on a 6890N MSD/DS Agilent Technologies chromatograph (USA) with a 5973N mass spectrometric detector. The components of essential oils were identified by comparison of the retention indices and mass spectra of phytochemicals in the studied essential oils with the data of NIST02 mass spectral library. The quantification of substances in the raw materials was carried out in comparison with a standard sample of menthol. Results. As a result, 72 compounds were detected and quantified. The total content of essential oil in V. longifolia L. flowers was 0.17 % (39 components), the following compounds dominated: benzoacetaldehyde – 8.05, squalene – 5.17, palmitic acid – 15.73, butyl phthalate – 7.18. The total content of essential oil in V. incana L. flowers was 0.15 % (43 components), the following compounds prevailed: squalene 20.47, fatty acids, namely palmitic – 26.88, palmitoleic – 17.15, oleic – 11.61. The total content of the essential oil in V. spicata L. flowers was 0.11 % (43 components), the following compounds dominated: squalene – 5.53, fatty acids: palmitic – 22.78, linoleic – 6.72, carbohydrates: heptacosan – 12.27, hexacosan – 7.45. Among the identified compounds, mono-, norsesqui-, sesqui-, di- and triterpenoids, their oxidation products (aromatic compounds, aldehydes and alcohols, ketones), fatty acids, hydrocarbons and their derivatives were detected. Conclusions. The chemical composition of essential oils from flowers of V. longifolia L., V. incana L. and V. spicata L. from Ukrainian flora was first studied by means of chromatography mass spectrometry. The yield of essential oil from V. longifolia L. flowers is higher (0.17 %) compared to those from flowers of V. incana L. (0.15 %) and V. spicata L. (0.11 %). Among the identified compounds terpenoids, aromatic compounds, their oxidation products, fatty acids and their esters, hydrocarbons were detected. The study of biologically active substances in essential oils from Veronica species flowers expands the scientific data on the chemical composition of these species and gives background for the further development of medicinal products, their standardization and understanding of their pharmacological activity