Biologically Active Compounds and Antioxidant Activity of the Plants from the Mountain Altai of the Caragana Genus

Objective: 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, and C. spinosa, growing in the Mountain Altai. Methods: The content of flavonols was determined by the spectrophotometric method on the SF-56 spectrophotometer in the presence of aluminum chloride, using CO rutin (Chemapol) as a reference substance. Phenolic compounds (flavonols, catechins, tannins), pectin substances (pectin and protopectin), pigments (carotenoids and chlorophylls) and the total content of phenolic antioxidants were analyzed in the aboveground organs of Caragana. Results and Discussion: 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 mg/g), tannins (117.2 mg/g), and carotenoids (0.56 mg/g) 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%). Differences in the content of photosynthetic pigments (chlorophylls and carotenoids) in the shoots of the studied Caraganas were revealed. 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. Conclusions: 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.