The paper focuses on the growth dynamics and biosynthetic characteristics of the microshoot culture of Spiraea betulifolia ssp. aemiliana obtained in vitro in agar-solidified and liquid media. Microshoots cultured in either type of media showed similar growth dynamics. The most active culture growth was observed from day 35 to day 60. A comparative analysis of the contents of flavonoids and phenol carboxylic acids showed a higher level of phenol carboxylic acids (5.3–6.84%) and a stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical–scavenging activity (half-maximal inhibitory concentration: 341 µg/mL) in S. betulifolia ssp. aemiliana microshoots grown in the liquid medium compared to the microshoots cultured in the solid medium. The flavonoid content of the cultured microshoot did not depend on the consistency of the medium. High-performance liquid chromatography (HPLC) was employed to study the profile and levels of phenolic compounds in microshoots, intact plants, and ex vitro–acclimated S. betulifolia ssp. aemiliana plants. The concentration of kaempferol glycosides was found to be higher in microshoots (1.33% in the solid medium, 1.06% in the liquid medium) compared to intact plants and ex vitro–acclimated plants. Thus, the microshoots of S. betulifolia ssp. aemiliana cultured in the liquid medium rapidly increase their biomass and are an inexpensive promising source of biologically active antioxidant substances, mainly phenol carboxylic acids and kaempferol glycosides.

Eranthis longistipitata Regel is an endemic plant of Central Asia. The flavonoid profile of E. longistipitata leaves was studied by mass spectrometry for the first time (natural populations of Kyrgyzstan and Uzbekistan, in 70% aqueous–ethanol extracts by liquid chromatography coupled with high-resolution mass spectrometry). Mass spectrometry revealed 18 flavonoid compounds. Flavonols featured the highest diversity, and 10 such substances were identified: 2 free aglycones (quercetin and kaempferol), 6 quercetin glycosides (peltatoside, hyperoside, reynoutrin, quercetin 3-sambubioside, rutin, and isoquercitrin), and 2 kaempferol glycosides (juglalin and trifolin). Two flavans (cianidanol and auriculoside), two hydroxyflavanones (6-methoxytaxifolin and aromadendrin), and one C-glycoside flavone—carlinoside—were identified. Dihydroxychalcones aspalathin, phloridzin, and phloretin were found too. Levels of rutin, quercetin, kaempferol, and hyperoside were confirmed by means of standards and high-performance liquid chromatography. Rutin concentration was the highest among all other identified flavonoid compounds: in the leaf samples from Kyrgyzstan, it ranged from 2.46 to 3.20 mg/g, and in those from Uzbekistan, from 1.50 to 3.01 mg/g. The diversity of flavonoid compounds in E. longistipitata leaves is probably due to external ecological and geographic factors and adaptive mechanisms.

In this study, growth parameters of underground parts and concentrations of phenylpropanoids, phenylethanoids, flavonoids, hydroxybenzoic acids, and catechins in aqueous–ethanol extracts of 6-year-old cultivated plants of Rhodiola rosea (propagated in vitro) of Altai Mountain origin were analyzed, and differences in chemical composition among plant specimens and between plant parts (rhizome and root) were evaluated. High-performance liquid chromatography detected 13 phenolic compounds. Roots contained 1.28 times higher phenylethanoids levels (1273.72 mg/100 g) than rhizomes did. Overall, the concentration of phenylethanoids in underground organs was not high and ranged from 21.36 to 103.00 mg/100 g. High variation among R. rosea individual plants was noted both in growth characteristics and in levels of secondary metabolites under our cultivation conditions. It was found that concentrations of phenylpropanoids, phenylethanoids, and catechins significantly depend on the plant part analyzed (p ≤ 0.05). Specimen No. 4 is characterized by the highest concentration of rosavins (1230.99 mg/plant) and the lowest concentration of cinnamyl alcohol (62.87 mg/plant). Despite the wide range of values, all 10 tested specimens (underground part) met the minimum requirements of the United States Pharmacopeia (2015) for rosavins (0.3%) and of the Russia State Pharmacopoeia (2015) for the average level of rosavins (roots): (1%).

Paeonia obovata and Paeonia oreogeton belong to the monotypic family Paeoniaceae. Both are popular as ornamental plants. P. obovata and P. oreogeton have been introduced into Novosibirsk Oblast (Western Siberia) from Primorye (Far East). The aim of the study was to assess their adaptability as well as the effect of seasonal developmental stages on the accumulation of secondary metabolites and reserve substances in the leaves and rhizomes under the conditions of Akademgorodok (Novosibirsk, Russia). According to long-term data (15 years), P. obovata and P. oreogeton complete the entire growth cycle here, including flowering and fruiting. Both species exhibited abundant flowering, but in the first 3 years, P. oreogeton did not bloom; yet under the microclimatic conditions specifically selected for this species (a more shaded area), it started to bloom and fruit yearly. A biochemical analysis (by spectrometric method) of P. obovata and P. oreogeton grown in Akademgorodok showed that the leaves accumulate higher concentrations of flavonols (P. obovata: 1.77%), tannins (P. oreogeton: 16.42%), ascorbic acid (P. oreogeton: 155.2 mg/100 g), and sugars (P. obovata: 20.85%) as compared to the roots. Peony rhizomes contain higher concentrations of protopectins (P. oreogeton: 13.03%), saponins (P. obovata: 21.06%), and starch (P. obovata: 30.20%) than the leaves do. These data can help to increase the levels of these natural compounds in these species. Further investigation into the dynamics of accumulation of biologically active substances in the organs of peonies will help to identify introduced plant species having high biochemical potential for the pharmaceutical industry.

Plants in high-altitude habitats are exposed to severe environmental stressors, including extreme temperatures and irradiation, which can have wide-ranging effects on changes of secondary-metabolite profiles in higher plants. Altitude-related variation of levels of polyphenols in organs of medicinal and food plant species has not yet been investigated sufficiently. This study was focused on variation in quantitative profiles of classes and of individual biologically active phenolic compounds in leaf extracts of resource species Spiraea chamaedryfolia and Spiraea media from the family Rosaceae in coenopopulations of the Altai Mountains, along an altitudinal gradient. High-performance liquid chromatography revealed 22 polyphenolic compounds in the extracts of S. media leaves, with the main polyphenolic compounds being flavonols. Sixteen compounds were found in S. chamaedryfolia leaf extracts, and the major ones were flavonols and a flavanone. Opposite responses to changes in the altitude-associated growth conditions were documented for levels of some individual polyphenolic compounds. With an increase in altitude, concentrations of chlorogenic acid and of flavanone in the extracts of S. chamaedryfolia leaves significantly increased, while concentrations of cinnamic acid, astragalin, and kaempferol diminished. A statistically significant positive correlation between the altitude of plant habitats and total levels of polyphenols and phenolcarboxylic acids was detected. In leaf extracts from S. media, an altitude increase was significantly positively correlated with astragalin, avicularin, and cinnamic acid levels and negatively correlated with hyperoside concentration.

Spiraea hypericifolia L. is affiliated with the section Chamaedryon Ser. of the genus Spiraea L. (Rosaceae). Similar to many other Spiraea species, S. hypericifolia most often accumulates flavonols among other flavonoids, in particular quercetin and its derivatives. An ethanol–water extract from the aerial part of S. hypericifolia collected in the vicinity of the Ilyichovo settlement (Krasnoyarsk Krai, Russia) was analyzed by liquid chromatography with high-resolution mass spectrometry. Primary and secondary metabolites were found in the extract; structural interpretation consistent with quercetin and its derivatives was proposed for 10 of them. Major compounds were various glycosides of quercetin containing glucose (four compounds), galactose (one compound), xylose (two compounds), arabinose (one compound), or rutinose (one compound) as a carbohydrate residue. Isorhamnetin and 3-O-methylquercetin-3′-O-β-D-glucopyranoside were identified among methyl-containing compounds. The latter compound and reynoutrin, rhamnetin-3-O-β-D-xylopyranosyl-β-D-glucopyranoside, and quercetin-3-O-(6″-O-malonyl)-β-D-glucoside have not been previously found in S. hypericifolia. Data on the presence of quercetin and its derivatives in the extract of S. hypericifolia expand the understanding of the possible practical use of this plant. In addition, the microscopic features of S. hypericifolia leaves were studied. The diagnostic features of the leaf blade necessary for the authentication of raw materials were revealed: straight-walled epidermis cells, stomata located on both sides of the leaf blade (amphistomatic type), two types of trichomes, and wrinkled cuticula with nodi. The main anatomical diagnostic features of the leaves of S. hypericifolia were determined, which makes it possible to assess the authenticity of the raw material.