Carboxylic acids in the flowers of Veronica spicata L. and Veronica incana L.

Abstract

In the Ukrainian flora, species of Veronica L. genus (Plantaginaceae Juss.) are classified into 8 sections. Among the representatives of Pseudolysimachion W. D. J. Koch section in the Kharkiv region, Veronica spicata L. (spike speedwell) and Veronica incana L. (Veronica spicata L. subsp. incana (L.) Walters, silver speedwell) are common. Plants are used for the treatment of upper respiratory tract diseases, malignant neoplasms, gastrointestinal tract and genitourinary system disorders, diabetes mellitus. The aim of the research was to study the carboxylic acids of flowers of Veronica spicata L. and Veronica incana L. Materials and methods. The objects of the research were flowers of Veronica spicata L. and Veronica incana L., collected in the flowering stage in the Botanical Garden of Karazin University (Kharkiv, Ukraine) in summer 2018. The study of carboxylic acid composition was performed by chromatography-mass spectrometry on a 6890N MSD/DS Agilent Technologies chromatograph with a 5973N mass spectrometric detector. Identification of methyl esters of acids was performed using data from the mass spectrum libraries NIST 05 and Willey 2007 in a combination with programs for the identification of AMDIS and NIST; also, their retention time and the retention times of standard compounds were compared. Results. In Veronica incana L. flowers, 37 carboxylic acids were identified and quantified, constituting 1.05 %. In Veronica spicata L. flowers, 32 carboxylic acids were identified and quantified, the total content of which was 2.75 %. Conclusions. A higher carboxylic acid content was established in the flowers of Veronica spicata L. The fatty acid composition of Veronica incana L. flowers is characterized by a comparable content of saturated and unsaturated acids, while in Veronica spicata L. flowers, unsaturated fatty acids prevail over saturated fatty acids. The content of aromatic acids in the flowers of studied species was comparable. The characteristic carboxylic acids in the flowers of Veronica incana L. are oxalic, 3-hydroxy-2-methylglutaric, pentadecanoic, heneicosanoic, tricosanic,4-hydroxybenzoic, 4-methoxybenzoic and 3,4-dimethoxybenzoic acids; in the flowers of Veronica spicata L. – 2-hydroxy-3-methylglutaric, α-furanic and homovanillic acids