COMPARATIVE STUDY OF FLAVONOID COMPOSITION OF LEAVES OF PHARMACOPEIAL SPECIES OF THE GENUS POPULUS

Abstract

The comparative study of the flavonoid composition of leaves of black poplar (Populus nigra L.), balsamic poplar (Populus balsamifera L.), canadian poplar (Populus deltoides Marsh.) and laurel poplar (Populus laurifolia Ledeb.) was held to determine the most perspective species as source of biologically active compounds. Nowadays poplar buds are registered as pharmacopeial medicinal raw material with antimicrobial, antifungal, anti-inflammatory and wound healing effects. It is also known that poplar leaves are used in folk medicine as an analgesic, antibacterial and anti-inflammatory agent. The leaves are also considered to be a perspective medicinal plant raw material along with buds. As a result of the comparative chromatographic analysis using detection at a wavelength of 366 nm and an alcoholic solution of aluminum chloride (AlCl3), rutin was found in all investigated extracts from the leaves of pharmacopeial species of poplars. Moreover, in extracts from Populus balsamifera L. and Populus laurifolia Ledeb. was revealed the presence of pinostrobin. It was determined that in all UV spectra of extracts from the leaves of the investigated poplar species, a long-wave batochromic shift were observed in the presence of 3% alcohol solution AlCl3, which indicates the presence of flavonoids. In the conditions of differential spectrophotometry, the maximum absorption in the range of 406–412 nm was observed, which indicates the necessity of using rutin standard which have maximum absorption at a wavelength of 414±2 nm. The content of the total flavonoids at the wavelength of 414 nm calculated on rutin in all samples was determined, which varies from 2.04% to 4.61% and corresponds to the recommended lower limit of the content of the total flavonoids (not less than 2.0%).