Study of Economically Valuable Features of Nepeta grandiflora M. Bieb. Genotypes in the South Steppe of Ukraine

Abstract

Nepeta grandiflora M. Bieb. known as aromatic, medicinal, and ornamental plants, whose extracts contain biologically active compounds. The essential oil of this species is a rich source of valuable components. This study aimed to evaluate plants' biological features and the biochemical content of the essential oil of N. grandiflora genotypes grown in the South of Ukraine. Genotypes G1-21, G2-20, G3-22, G4-20, and G5-21 were investigated for morphometric and some biological features in the flowering stage. In the genotype, plants were measured the length and width of inflorescences (in cm), the number of whorls in the inflorescences, the number of flowers in the semi-whorls. The essential oil was obtained from the herb in the flowering stage; the mass fraction of the essential oil was determined by the hydrodistillation method (Ginsberg’s method) on the Clevenger apparatus. The study of the component composition of the essential oil (on the sample G1-21) was carried out by high-performance gas-liquid chromatography method. As a result, the length of the inflorescences was from 10.55 (G5-21) to 33.27 (G4-20) cm, the width of inflorescences from 3.52 (G3-22) to 6.51 (G4-20) cm, the number of whorls in inflorescences from 8.09 (G5-21) to 12.97 (G3-22) cm, number of flowers in semi-whorls from 10.58 (G4-20) to 39.38 (G1-21) depends on genotype. The essential oil content on dry weight was from 0.16 (G4-20) to 0.37 (G1-21) %. The prevailing components of the investigated essential oil of G1-21 were caryophyllene (17.46%) and germacrene D (17.80%); 1,8-cineol (8.83 %), caryophyllene oxide (7.62 %), germacrene D–epoxide (6.73 %), etc. found in less quantitative. Thus, the obtained data concerning the N. grandiflora plants showed differences in essential oil content and selected morphometrical parameters of plants depending on genotype. Also, the essential oil of N. grandiflora (G1-21) contains the principal chemicals that can be used in further pharmacological investigations, cosmetic, and food industries.