VARIABILITY OF THE INDIVIDUAL-GROUP COMPOSITION OF POLYPHENOLS OF THE FRUITS AND LEAVES OF BLUE HONEYSUCKLE SAMPLES OF DIFFERENT ECOLOGICAL AND GEOGRAPHICAL ORIGIN IN THE OB FOREST-STEPPE

Abstract

The aim of the study was to compare the variability of the composition, chemical identity and content of biologically active phenolic compounds in the fruits and leaves of the blue honeysuckle (Lonicera subsection Caeruleae) plants of different environmental and geographic provenances, sampled from the introduction plantation station in the forest steppe zone near the Ob River (Novosibirsk, Russia). In extracts from the leaves 25 individual compounds representing various polyphenolic classes were identified using HPLC-MS technique; seven of the compounds were identified as hydroxycinnamic acids, five compounds were flavonols, and eight compounds represented flavones. The maximal number of individual compounds was present in samples of the Altai subspecies of the tetraploid species L. caerulea subsp. altaica, whereas the minimal number was detected in samples of L. boczkarnikowae, a diploid species from the Russian Far East (Primorsky region). The lowest total polyphenolics content (6,260 mg/100 g of air-dry phytomass) was found in samples of L. caeruleae subsp. pallasii, whereas the content in samples from other blue honeysuckle subspecies ranged within 11.620-14.030 mg/100 g of air-dry phytomass. High content of flavones in extracts from leaves, always exceeding the flavonol content, was found to be a characteristic feature of L. caerulea subsp. altaica. Among L. сaerulea subspecies, L. сaerulea subsp. pallasii was shown to have the largest ratio of flavonols to flavones. L. boczkarnikowae also had high content of flavonols, significantly exceeding the flavones content in the plants organs. The main component of anthocyanins was cyanidin-3-glucoside, accounting for up to 91%. The fruits of L. caerulea subsp. altaica, L. сaerulea subsp. venulosa and L. boczkarnikowae had the highest anthocyanin content, ranging 2.950–3.200 mg/100 g air-dry phytomass, whereas the fruits of L. сaerulea subsp. pallasii had the lowest one (1,573 mg/100g). Extracts from the leaves were found to have significantly higher polyphenolics content as compared to the ones from the fruits; thus the leaves can be recommended as a prospective medicinal source.