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The aim of this work was to determine the component composition and quantitative content of flavonoids, including catechins, in the leaves, shoots and fruits of Virginia creeper (Parthenocissus quinquefolia (L.) Planch.) for further standardization of raw materials and establishing antioxidant activity of their water-ethanol extracts. Materials and methods. The leaves, shoots of Parthenocissus quinquefolia were collected during the phase of mass flowering in July 2020 and fruits were collected during full ripeness (September-October 2020) in Lisnyky village of Obukhiv district of Kyiv Oblast (Ukraine). Determination of the component composition and quantitative content of flavonoids, including catechins, was carried out by the method of high-performance liquid chromatography (HPLC) on an Agilent Technologies 1200 liquid chromatograph. Identification and quantitative analysis were carried out using standard solutions of flavonoids (rutin, quercetin-3-β-glycoside, naringin, neohesperidin, quercetin, naringenin, kaempferol, luteolin, apigenin) and catechins (pyrocatechin, catechin, epicatechin, epicatechin gallate and halocatechin). Antioxidant activity was determined by the spectrophotometric method at 347 nm by the ability to inhibit the autooxidation of adrenaline in vitro. Results. As a result of the study, 9 phenolic compounds were identified: rutin, quercetin, quercetin-3-β-glycoside, naringin, epicatechin, catechin, gallocatechin, epicatechin gallate. It was determined that rutin, quercetin, epicatechin, and catechin predominate in the leaves, shoots, and fruits of Virginia creeper. It was established that the extracts of leaves with shoots and fruits of Virginia creeper show a pronounced antioxidant activity due to their ability to inhibit autooxidation of adrenaline in vitro. Conclusions. The high content of rutin, quercetin, epicatechin and catechin in the leaves, shoots and fruits of Virginia creeper has scientific interest, due to discovered compounds have a valuable pharmacological effect. The obtained results can be used for the standardization of raw materials of Virginia creeper, and differences in the quantitative content of halocatechin in different types of raw materials, as well as the presence of naringin in leaves and shoots and luteolin in the fruits of Virginia creeper as diagnostic features of this species raw material. The results of the study of antioxidant activity confirm the prospects of using this raw material for the creation of new drugs with antioxidant activity. [ABSTRACT FROM AUTHOR]

The aim of the work was to determine the main groups of polyphenolic compounds in Quercus rubra L. raw materials. Materials and methods. The leaves and annual shoots of Northern Red Oak used for research were collected in August in Lisnyky village of Obuhiv district of Kyiv Oblast (Ukraine). Determination of the component composition and quantitative content of flavonoids (including separately catechins), hydroxycinnamic acids, and phenolic acids were carried out in the samples of air-shade-dried crushed raw material to a particle size of 3 mm by the method of high-performance liquid chromatography (HPLC). Agilent Technologies 1200 liquid chromatograph was used for liquid chromatography. Results. Using the HPLC method, 18 polyphenolic compounds were identified in leaves and annual shoots of Northern Red Oak, in particular, flavonoids: rutin, quercetin-3-β-glucoside, luteolin, neohesperidin; catechins: catechin, epicatechin, epicatechin gallate, gallocatechin; hydroxycinnamic acids: chlorogenic, caffeic, trans-ferulic, trans-cinnamic, p-coumaric, hydroxyphenylacetic, benzoic, syringic, sinapic acids; phenolic acid is gallic acid. The dominant component among flavonoids is rutin (323.43 mg/100 g) (in the composition of catechins, epicatechin gallate (25.45 mg/100 g) prevails); among hydroxycinnamic acids in Northern Red Oak raw materials, chlorogenic acid (139.62 mg/100 g) and sinapic acid (74.64 mg/100 g) prevail. Conclusions. The obtained results point to the prospects of further phytochemical and pharmacological studies of Quercus rubra raw materials, with the aim of creating new plant substances based on it with antioxidant, anti-inflammatory, and antiviral activity. [ABSTRACT FROM AUTHOR]