Application HPLC for search of non-traditional anthocyanin sources. Anthocyanins of Acer platanoides "Crimson King" eaves
Reversed-phase HPLC was used for investigation of anthocyanins in non-traditional sources - in leaves of two Acer species. Anthocyanins type composition was determined in leaves of the red-leaves Acer platanoides L., variety «Crimson King» (I) and fan Japanese maple, Acer palmatum (Thunbergii) Rehdo, variety «Bloodgood» (II) from the Botanical garden of Belgorod National Research university. It was found that the main anthocyanins in I are cyanidin-3-glucoside (39-86 mole %) and that acylated with the gallic acid (10-55 mole %) in the presence of a small amount (1-3 %) of double acylation. The degree of acylation may vary for leaves depending on different conditions. For II, the main difference was established as biosynthesis of not only cyanidin-3-glucoside, but also cyanidin-3-rutinoside (30 mole %) with some acylation of both compounds by the gallic acid. High hydrophilicity of gallic acid substituent is resulted in relatively low rise of retention of acylated anthocyanins, thus isocratic mode of chromatographic runs is possible to separate all compounds under interest. The separation map of the substances is proposed for 150x4.6 mm Symmetry C18 (3.5 pm) column and 10 vol.% of formic acid, acetonitrile and water mobile phases. The level of antho-cyanin accumulation is not constant for leaves collected at different times and from different parts of the tree. Meanwhile intensively crimson-colored leaves I can accumulate more than 0.200 g of anthocyanins per 100 g of fresh leaves (by cyaniding-3-glucoside chloride equivalent), whereas in leaves II the concentration of anthocyanins can be 2-2.5 higher (above 0.500 g per 100 g of fresh leaves). Drying leaves does not lead to significant destruction of anthocyanins.