FLAVONOIDS OF THE FAR EASTERN SPECIES OF THE GENUS BUPLEURUM L.

Abstract

Compounds of the flavonoid class were isolated from six species of plants of the genus Bupleurum L. growing in the Russian Far East (Primorsky Krai, Magadan Region) by liquid extraction. Five compounds were identified by reversed-phase liquid chromatography: avicularin, rutin, narcissin, quercetin, isorhamnetin. Avicularin has been identified in the plants B. atargense, B. longiradiatum for the first time. The structure of compounds (avicularin, rutin, narcissin) isolated by preparative column chromatography on silica gel in the gradient elution mode with a mixture of solvents (carbon tetrachloride and ethyl alcohol) was proved by NMR-1H, 13C, 1H,13C-HMBC spectroscopy and mass spectrometry with ESI. The sum of flavonoids in the aerial part of six species of the genus Bupleurum L. was determined by differential spectrophotometry, the mass fraction of which varies from 0.58 to 2.92%. The highest content of flavonoids was found in B. euphoiroides – 2.92±0.58%, and the least – in B. longiradiatum (0.58±0.12%). Comparative analysis of individual flavonoids in species of the genus Bupleurum L. revealed the specificity of their accumulation. The main flavonoid in the aerial part of B. atargense, B. euphoiroides is quercetin – 1.14±0.23%, 0.92±0.18%, and in B. triradiatum, B. komarovianum, B. scorzonerifolium, B. longiradiatum – rutin (0.47±0.09%, 0.18±0.04%, 0.32±0.08%, 0.13±0.03% accordingly).