The content of biologically active substances and the level of antioxidant activity in the aerial organs of different sexual forms of Sibiraea altaiensis (Laxm.) Schneid. during the growing season were investigated for the first time. It was found that the maximum content of biologically active compounds varies depending on the stage of development, plant organ and also gender. The amount of flavonols (5.69%), tannins (30.17%) is higher in the leaves of male plants during the budding of plants, catechins ‒ in inflorescences (0.61%) of female plants, pectins ‒ in male buds (1.54%), protopectins ‒ in the leaves of males (8.99%) in the budding phase and in the leaves of females (9.62%) in the fruiting phase of plants and carotenoids ‒ in the leaves of males (70.6 mg%) and female (61.86 mg%) plants in the fruiting phase. Stalks of S. altaiensis contain quite a high amount of tannins (20.1%), pectins (1.49%), protopectins (5.93%) and carotenoids (17.37 mg%). The highest (antioxidant activity) AOA was detected in water (2.03 mg/g) and water-ethanol (1.75 mg/g) extracts from the leaves of male S. altaiensis plants. The AOA of water and water-ethanol extracts from the aerial organs of S. altaiensis is authentically positively connected with the content of all the studied substances, except for pectins.

Studied the content the content of phenolic compounds (flavonols, flavans (catechins), tannins), polysaccharides (pectins, protopectins), tetraterpenes (carotenoids) and antioxidant activity of Cichorium intubus L., Taraxacum officinale Wigg., Arnica iljinii (Maguire) Iljin., Echinops sphaerocephalus L. cultivated in conditions of Western Siberia. A significant part of the biologically active substances are tannins (up 28.25%) and protopectins (up 11.11%). The content of flavonoids in the studied samples of C. intybus plants corresponds to the indicators of chicory grass for other regions of the Russian Federation, including the regions of its industrial cultivation. The flowers and leaves of the studied samples of T. officinale are characterized by approximately the same content of flavonols (1.02–1.43%), pectins (0.80–1.08%) and protopectins (7.94–8.87%). The leaves and flowers of A. iljinii are distinguished by a rather high content of flavonols (up to 4.23%) and tannins (up to 28.25%). In terms of the content of tannins (8.34%), catechins (36.3 mg/%), protopectins (10.06%) and carotenoids (64.60 mg/%), the leaves of E. sphaerocephalus are significantly superior to the flowers. Flavonols are present in equal proportions in leaves (0.68%) and flowers (0.64%). Indicators of the total content of phenolic antioxidants in the leaves and flowers of C. intubus, T. officinale, A. iljinii, E. sphaerocephalus do not differ significantly.

The article presents Data on the content of biologically active compounds (BAC) and the total phenolic antioxidants activity (TPA) evaluated for aboveground organs of three species from the Caragana Genus – C. bungei, C. pygmaea и C. spinosa, growing in the Mountain Altai. It was determined that leaves and reproductive organs contain flavonols, catechins, tannins, carotenoids, pectin substances. It is shown that biologically active substances of a plant are synthesized differently depending on the species, habitat and organ of the plant. The highest level of flavonols (36.4 мг/г), tannins (117.2 мг/г) and carotenoids (0.56 мг/г) was registered in leaves of C. spinosa. Catechins predominantly accumulated in the leaves of C. pygmaea (up to 211.3 mg/100g) and inflorescences of C. bungei (up to 205 mg/g). The content of pectin substances was quite high, with the biggest share of protopectins. The highest level of protopectins was registered in inflorescences of C. bungei (5.81%) and leaves of C. pygmaea (3.58%). Pectins are synthesized more in the flowers of C. bungei (0.74%) and leaves of C. spinosa (0.49%). The highest values of antioxidant activity were found in the water–ethanol extracts from the leaves of C. spinosa (1.61 mg/g), which is probably due to the increased content of flavonols and tannins. It was shown that the antioxidant activity of Caragana plants is 71% determined by the content of tannins, 62% by the content of flavonols and 41% by the content of carotenoids. C. spinosa is more promising for finding sources of antioxidants.

The content of biologically active substances and antioxidant activity in leaves and inflorescences of three species from the tribe Cynareae of the Asteraceae family: Centaurea cyanus,Centaurea macrocephala, Rhaponticum carthamoides, grown under the conditions of the Central Siberian Botanical Garden introduction was studied. It was determined that leaves and inflorescences contain flavonols, catechins, tannins, carotenoids, pectin substances. The highest level of tannins (up to 27.7%) in leaves and flavonols in leaves and inflorescences (up to 4.93 %) was found in plants of R. carthamoides. High content of catechins (up to 140.2 mg%) was found in leaves and inflorescences of C. macrocephala. Carotenoids are mainly accumulated in leaves of R. carthamoides (51.73 mg%) and inflorescences of C. macrocephala (11.86 mg%). The highest content of pectins was noted in leaves and inflorescences of C. cyanus (1.7% and 2.6%), protopectins - in leaves (up to 10.54 %). The highest antioxidant activity (0.72 мг/г) and anti-radical activity (IC50=0.58–0.77 мг/г) were recorded for water-ethanol extracts from leaves and inflorescences of C. macrocephala. Water-ethanol extracts of C. cyanus exhibited low antiradical activity (IC50=4.43–8.13 mg/g).