Chemodiversity of Arctic Plant Dryas oxyodonta: LC-MS Profile and Antioxidant Activity.

Dryas oxyodonta Yuz. is a perennial evergreen shrub from the Rosaceae family. D. oxyodonta thrives in subalpine and subarctic regions, as well as in highlands spanning from Central Asia to Siberia and Mongolia. Owing to a lack of information on its chemical composition, we conducted qualitative and quantitative chromatographic analyses on extracts from the leaves and flowers of D. oxyodonta sourced from various Siberian habitats. Employing high-performance liquid chromatography with photodiode-array detection and electrospray ionization triple-quadrupole mass spectrometric detection, we identified 40 compounds, encompassing gallotannins, hydroxycinnamates, procyanidins, catechins, flavonoids, and triterpenes. All Siberian populations of D. oxyodonta exhibited a notable abundance of phenolic compounds. Furthermore, we identified rare glycosides, such as sexangularetin and corniculatusin, as potential markers of the chemodiversity within the Dryas genus. Extracts from the flowers and leaves were effective scavengers of free radicals, including DPPH•, ABTS•+-, O2•-, and •OH radicals. Our findings unequivocally establish D. oxyodonta as a rich source of phenolic compounds with potent antioxidant activity, suggesting its potential utility in developing novel functional products.

Gentianopsis metabolites and bioactivity: HPLC-PDA-ESI-tQ-MS/MS profiles, HPLC-UV quantification of Gentianopsis komarovii and Gentianopsis stricta, and choleretic potential.

Gentianopsis is a small gentianaceous genus with a known ethnopharmacological focus as hepatoprotectors containing two underestimated species that are scientifically unexplored: Gentianopsis komarovii (Grossh.) Toyok., which is typical of the Far East, and Gentianopsis stricta (Klotzsch) Ikonn., which is grown in Central Asia. Application of the HPLC-PDA-ESI-tQ-MS/MS technique led to the identification of 28 compounds, such as iridoid glycosides, flavones and xanthones, with loganic acid, sweroside, loganin, secologanin, isoorientin-7-O-glucoside, luteolin-7-O-gentiobioside, chrysoeriol-7-O-glucoside and acacetin-7-O-glucoside being found in the genus for the first time. The extracts of G. komarovii and G. stricta demonstrated choleretic potential, strengthening the bile flow and the total content of bile acids, bilirubin and cholesterol in the bile. The most pronounced effects were observed for luteolin-7-O-glucoside and gentiabavaroside (gentiacaulein-1-O-primveroside), establishing them as the principle choleretics of both herbs. Based on the results, G. komarovii, G. stricta and some phenolic metabolites are prospective new choleretic drugs.

Metabolites of Geum aleppicum and Sibbaldianthe bifurca: Diversity and α-Glucosidase Inhibitory Potential.

α-Glucosidase inhibitors are essential in the treatment of diabetes mellitus. Plant-derived drugs are promising sources of new compounds with glucosidase-inhibiting ability. The Geum aleppicum Jacq. and Sibbaldianthe bifurca (L.) Kurtto & T.Erikss. herbs are used in many traditional medical systems to treat diabetes. In this study, metabolites of the G. aleppicum and S. bifurca herbs in active growth, flowering, and fruiting stages were investigated using high-performance liquid chromatography with photodiode array and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS). In total, 29 compounds in G. aleppicum and 41 components in S. bifurca were identified including carbohydrates, organic acids, benzoic and ellagic acid derivatives, ellagitannins, flavonoids, and triterpenoids. Gemin A, miquelianin, niga-ichigoside F1, and 3,4-dihydroxybenzoic acid 4-O-glucoside were the dominant compounds in the G. aleppicum herb, while guaiaverin, miquelianin, tellimagrandin II2, casuarictin, and glucose were prevailing compounds in the S. bifurca herb. On the basis of HPLC activity-based profiling of the G. aleppicum herb extract, the most pronounced inhibition of α-glucosidase was observed for gemin A and quercetin-3-O-glucuronide. The latter compound and quercetin-3-O-arabinoside demonstrated maximal inhibition of α-glucosidase in the S. bifurca herb extract. The obtained results confirm the prospects of using these plant compounds as possible sources of hypoglycemic nutraceuticals.

Hogweed Seed Oil: Physico-Chemical Characterization, LC-MS Profile, and Neuroprotective Activity of Heracleum dissectum Nanosuspension.

The seeds of dissected hogweed (Heracleum dissectum Ledeb., Apiaceae) are the source of hogweed oil (HSO), which is still underexplored and requires careful chemical and biological studies. The performed physico-chemical analysis of HSO elucidated basic physical characteristics and revealed the presence of fatty acids, essential oil components, pigments, and coumarins. High-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS) identified 38 coumarins that were characterized and quantified. Various furanocoumarins were the major components of HSO polyphenolics, including imperatorin, phellopterin, and isoimperatorin, and the total coumarin content in HSO varied from 181.14 to 238.42 mg/mL. The analysis of storage stability of the selected compounds in HSO indicated their good preservation after 3-year storage at cold and freezing temperatures. The application of the CO2-assisted effervescence method allowed the production of an HSO nanosuspension, which was used in a brain ischemia model of rats. The HSO nanosuspension enhanced cerebral hemodynamics and decreased the frequency of necrotic processes in the brain tissue. Thus, H. dissectum seeds are a good source of coumarins, and HSO nanosuspension promotes neuroprotection of the brain after lesions, which supports earlier ethnopharmacological data.

New Inonotus Polysaccharides: Characterization and Anticomplementary Activity of Inonotus rheades Mycelium Polymers.

Inonotus is a small genus of xylotrophic basidiomycetes and a source of bioactive fungochemicals among which a special place is occupied by polymeric compounds. In this study, polysaccharides that are widespread in Europe, Asia, and North America and a poorly understood fungal species, I. rheades (Pers.) Karst. (fox polypore), were investigated. Water-soluble polysaccharides of I. rheades mycelium were extracted, purified, and studied using chemical reactions, elemental and monosaccharide analysis, UV-Vis and FTIR spectroscopy, gel permeation chromatography, and linkage analysis. Five homogenic polymers (IRP-1-IRP-5) with molecular weights of 110-1520 kDa were heteropolysaccharides that consist mainly of galactose, glucose, and mannose. The dominant component, IRP-4, was preliminary concluded to be a branched (1→3,6)-linked galactan. Polysaccharides of I. rheades inhibited the hemolysis of sensitized sheep erythrocytes by complement from human serum, signifying anticomplementary activity with the greatest effects for the IRP-4 polymer. These findings suggest that I. rheades mycelium is a new source of fungal polysaccharides with potential immunomodulatory and anti-inflammatory properties.

Protective effects of Leuzea uniflora (Rhaponticum uniflorum) on the brain mitochondrial function in white rats at hypoxia/reoxygenation.

Protective effects of Leuzea uniflora (L.) Holub (Rhaponticum uniflorum (L.) DC., Asteraceae) on the white rats' brain mitochondrial function in acute hypobaric hypoxia/reoxygenation were studied. The extract of L. uniflora in the dose of 100 mg/kg was administered to animals for 14 days. The effects of the extract on the brain mitochondria respiration rate as well as on the NADH- and succinate dehydrogenase activities were determined. The extract of L. uniflora increased the oxidative phosphorylation processes coupling in brain mitochondria, namely, it significantly stimulated basal respiration, caused an increase in NADH-oxidase and succinate dehydrogenase complexes activity, increased the ATP content, reduced the lipid peroxidation intensity and improved the antioxidant state. The results obtained indicate the presence of energy-protective and antioxidant activities of L. uniflora, which are due to its ability to reduce the oxidation of biomacromolecules in hypoxia/reoxygenation.

Caucasian Blueberry: Comparative Study of Phenolic Compounds and Neuroprotective and Antioxidant Potential of Vaccinium myrtillus and Vaccinium arctostaphylos Leaves

(1) Background: Two Caucasian blueberries Vaccinium myrtillus L. and Vaccinium arctostaphylos L. are famous berry bushes growing in the Caucasus region and used to treat neurological diseases, but the chemistry and bioactivity of leaf extracts are still poorly studied. (2) Methods: Phenolic compounds of V. myrtillus and V. arctostaphylos leaf extracts were profiled and quantified by HPLC-PDA-ESI-tQ-MS. The neurotropic potential of Vaccinium extracts was studied using the model of middle cerebral artery permanent occlusion to determine cerebral blood flow, the area of the brain tissue necrosis, and antioxidant enzyme activity (including superoxide dismutase, succinate dehydrogenase, and cytochrome C oxidase), as well as the concentration of TBARS. (3) Results: Hydroxycinnamates and flavonoids were identified in the leaves of V. myrtillus and V. arctostaphylos, and the dominant metabolite of both extracts was 5-O-caffeoylquinic acid in the amount of 105-226 mg/g. The studied extracts enhanced the cerebral hemodynamics and decreased the frequency of necrotic and lipooxidative processes in the brain tissue, accompanied by an increase in the activity of antioxidant enzymes. The positive effect of V. arctostaphylos was stronger and exceeded the effectiveness of Ginkgo biloba standardized extract. (4) Conclusion: The leaf extracts of Caucasian blueberries V. myrtillus and V. arctostaphylos as a new source of hydroxycinnamates demonstrated a protective effect of the brain ischemia pathology and can be used as therapeutic agents to treat neurological diseases.

Marigold Metabolites: Diversity and Separation Methods of Calendula Genus Phytochemicals from 1891 to 2022.

Marigold (Calendula), an important asteraceous genus, has a history of many centuries of therapeutic use in traditional and officinal medicines all over the world. The scientific study of Calendula metabolites was initiated at the end of the 18th century and has been successfully performed for more than a century. The result is an investigation of five species (i.e., C. officinalis, C. arvensis, C. suffruticosa, C. stellata, and C. tripterocarpa) and the discovery of 656 metabolites (i.e., mono-, sesqui-, di-, and triterpenes, phenols, coumarins, hydroxycinnamates, flavonoids, fatty acids, carbohydrates, etc.), which are discussed in this review. The identified compounds were analyzed by various separation techniques as gas chromatography and liquid chromatography which are summarized here. Thus, the genus Calendula is still a high-demand plant-based medicine and a valuable bioactive agent, and research on it will continue for a long time.

The Ethnopharmacological Uses, Metabolite Diversity, and Bioactivity of Rhaponticum uniflorum (Leuzea uniflora): A Comprehensive Review.

Rhaponticum uniflorum (L.) DC. (syn. Leuzea uniflora (L.) Holub) is a plant species of the Compositae (Asteraceae) family that is widely used in Asian traditional medicines in China, Siberia, and Mongolia as an anti-inflammatory and stimulant remedy. Currently, R. uniflorum is of scientific interest to chemists, biologists, and pharmacologists, and this review includes information from the scientific literature from 1991 to 2022. The study of the chemodiversity of R. uniflorum revealed the presence of 225 compounds, including sesquiterpenes, ecdysteroids, triterpenes, sterols, thiophenes, hydroxycinnamates, flavonoids, lignans, nucleosides and vitamins, alkanes, fatty acids, and carbohydrates. The most studied groups of substances are phenolics (76 compounds) and triterpenoids (69 compounds). Information on the methods of chromatographic analysis of selected compounds, as well as on the quantitative content of some components in various organs of R. uniflorum, is summarized in this work. It has been shown that the extracts and some compounds of R. uniflorum have a wide range of biological activities, including anti-inflammatory, antitumor, immunostimulatory, anxiolytic, stress-protective, actoprotective, antihypoxic, anabolic, hepatoprotective, inhibition of PPARγ receptors, anti-atherosclerotic, and hypolipidemic. Published research on the metabolites and bioactivity of R. uniflorum does not include clinical studies of extracts and pure compounds; therefore, an accurate study of this traditional medicinal plant is needed.

Polymeric Compounds of Lingonberry Waste: Characterization of Antioxidant and Hypolipidemic Polysaccharides and Polyphenol-Polysaccharide Conjugates from Vaccinium vitis-idaea Press Cake.

Lingonberry (Vaccinium vitis-idaea L.) fruits are important Ericaceous berries to include in a healthy diet of the Northern Hemisphere as a source of bioactive phenolics. The waste generated by the V. vitis-idaea processing industry is hard-skinned press cake that can be a potential source of dietary fiber and has not been studied thus far. In this study, water-soluble polysaccharides of V. vitis-idaea press cake were isolated, separated, and purified by ion-exchange and size-exclusion chromatography. The results of elemental composition, monosaccharide analysis, ultraviolet-visible and Fourier-transform infrared spectroscopy, molecular weight determination, linkage analysis, and alkaline destruction allowed us to characterize two polyphenol-polysaccharide conjugates (PPC) as neutral arabinogalactans cross-linked with monomeric and dimeric hydroxycinnamate residues with molecular weights of 108 and 157 kDa and two non-esterified galacturonans with molecular weights of 258 and 318 kDa. A combination of in vitro and in vivo assays confirmed that expressed antioxidant activity of PPC was due to phenolic-scavenged free radicals, nitrogen oxide, hydrogen peroxide, and chelate ferrous ions. Additionally, marked hypolipidemic potential of both PPC and acidic polymers bind bile acids, cholesterol, and fat, inhibit pancreatic lipase in the in vitro study, reduce body weight, serum level of cholesterol, triglycerides, low/high-density lipoprotein-cholesterol, and malondialdehyde, and increase the enzymatic activity of superoxide dismutase, glutathione peroxidase, and catalase in the livers of hamsters with a 1% cholesterol diet. Polysaccharides and PPC of V. vitis-idaea fruit press cake can be regarded as new antioxidants and hypolipidemic agents that can be potentially used to cure hyperlipidemic metabolic disorders.

Caucasian Dragonheads: Phenolic Compounds, Polysaccharides, and Bioactivity of Dracocephalum austriacum and Dracocephalum botryoides.

Dracocephalum botryoides Steven and Dracocephalum austriacum L. are unexplored species of the Dracocephalum genus (Lamiaceae family) with a distribution in the Caucasus, where they are used in folk medicine and local cuisine. There are no data on the chemical composition of these Dracocephalum species. In this study, the application of a liquid chromatography-mass spectrometry technique for the metabolite profiling of methanol extracts from herbs and roots of D. austriacum and D. botryoides resulted in the identification of 50 compounds, including benzoic acid derivatives, phenylpropanoids, flavonoids and lignans. Water-soluble polysaccharides of the herbs and roots of D. austriacum and D. botryoides were isolated and characterized as mostly pectins with additive arabinogalactan-protein complexes and starch-like compounds. The antioxidant potential of the studied extracts of Dracocephalum and selected phenolics and water-soluble polysaccharides were investigated via radical-scavenging and ferrous (II) ion chelating assays. This paper demonstrates that herbs and roots of D. austriacum and D. botryoides are rich sources of metabolites and could be valuable plants for new biologically active products. To the best of our knowledge, this is the first study of whole plant metabolites and their antioxidant activity in D. austriacum and D. botryoides.

Coumarins of Lovage Roots (Levisticum officinale W.D.J.Koch): LC-MS Profile, Quantification, and Stability during Postharvest Storage.

Lovage (Levisticum officinale W.D.J. Koch) is a known aromatic apiaceous species that is widely used as a culinary and medicinal plant. Traditionally, more scientific attention has been paid to lovage volatiles, while other groups of compounds have been underutilized. In this study, metabolites of fresh lovage roots were investigated by liquid chromatography-mass spectrometry, and 25 compounds were identified, including coumarins as basic components and minor hydroxycinnamates; most were detected for the first time in the plant. Four major coumarins (including apterin, xanthotoxin, isopimpinellin, and pimpinellin) were successfully separated by a validated HPLC-PDA method, and the fresh roots of seven lovage cultivars as well as the dry roots of commercial lovage were quantified. The coumarin content deviation was 1.7-2.9 mg/g in the fresh roots and 15-24 mg/g in the dry roots. A variation in the coumarin level was found during storage of the fresh lovage roots at chill and room temperatures, while storage of the dried roots at room temperature showed the lowest loss of target compounds. This new information about the metabolites of lovage indicates the prospects of the plant roots as a source of dietary coumarins.

Antihypoxic activity of the dry extract from Nepeta multifida L.

The antihypoxic effect of the Nepeta multifida L. dry extract was studied in experiments on white Wistar rats. The life span of animals was determined against the background of acute hypoxias: hypercapnic, hemic, and histotoxic ones. Using the model of acute hypobaric hypoxia/reoxygenation there was evaluated the content of ATP, lactic and pyruvic acids, TBA-active products, reduced glutathione, catalase activity in brain tissue. On the model of acute hypobaric hypoxia/reoxygenation, the content of ATP, lactic and pyruvic acids, reduced glutathione and catalase activity in brain tissue The N. multifida dry extract demonstrated antihypoxic effect at the doses comprised between 100 and 300 mg/kg increasing lifespan of animals in hypercapnic, hemic and histotoxic hypoxias. N. multifida decreases the manifestation of free-radical oxidation processes, increases the activity of the endogenic antioxidant system, and promotes the efficacy of tissue respiration and oxidative phosphorylation coupling in the brain of white rats in hypoxia/reoxygenation.

Antioxidant Activity of Styrylpyrones from Inonotus rheades (Agaricomycetes) Mycelium under Oxidative Stress in Thellungiella salsuginea Cell Suspension Culture.

This study examined effects of the styrylpyrone fraction from mycelium of hymenochaetoid species, Inonotus rheades (Agaricomycetes), on reactive oxygen species inhibition in Thellungiella salsuginea cell culture under oxidative stress. We identified antioxidant effects of styrylpyrones from I. rheades mycelium on oxidative stress in T. salsuginea cell suspension culture using two models of oxidative stress (induced by hyperthermia or hydrogen peroxide). The results showed that the styrylpyrone fraction maintained a high level of cell viability under stress conditions. The effect of pure hispidin on the plant cell culture was insignificant during the development of oxidative damage caused by hydrogen peroxide and was lacking during hyperthermia-induced oxidative stress. Therefore, these results suggest that the protective effect of the styrylpyrone fraction on T. salsuginea cells can be exerted by individual compounds (which are part of the fraction) and their complex.

Rhaponticum uniflorum and Serratula centauroides Extracts Attenuate Emotional Injury in Acute and Chronic Emotional Stress.

In modern life, the use of plant stress-protectors has taken on particular significance due to the wide distribution of neurosis-like and neurotic diseases caused by neuroendocrine-immune system imbalance. Special attention has been paid to the plants containing ecdysteroids, i.e., hormone-like bioactive substances with high adaptogenic activity. The article deals with the study of bioactivity of two plant extracts as Rhaponticum uniflorum (L.) DC. and Serratula centauroides L. with a high content of ecdysteroids and phenolic compounds. The models of acute and chronic emotional stress in white rats were used to estimate the stress-protective activity of R. uniflorum and S. centauroides extracts. Both extracts showed the stress-protective effect via inhibiting the development of signs induced by single and long-term effects of stress factors. In acute stress, the development of Selye's triad signs was less pronounced against the background of the plant remedies introduction. In chronic stress, the extracts prevented the development of anxiety-depressive syndrome. Besides, R. uniflorum and S. centauroides extracts banned the development of stress-induced injuries in the brain cortex and had a neuroprotective effect on ischemia against chronic stress. The stress-protective effects of both plant extracts were based on a decrease of hyperactivation of the central stress-promoting systems (sympathoadrenal, hypothalamic-pituitary-adrenal) due to their GABA-mimetic effects. Peripheral mechanisms were connected with the inhibition of free radical oxidation processes and with an increase in the endogenous antioxidant system activity. Thus, R. uniflorum and S. centauroides extracts have a high potential to increase non-specific body resistance against acute and chronic emotional stress effects.

Metabolites of Siberian Raspberries: LC-MS Profile, Seasonal Variation, Antioxidant Activity and, Thermal Stability of Rubus matsumuranus Phenolome.

Rubus matsumuranus H. Lev. & Vaniot, a famous Siberian shrub of the Rosaceae family, is used in the folk medicine of nomads (Buryats, Yakuts, Soyots, and Mongols) as a remedy for the treatment of diseases of the respiratory and hepatobiliary systems. The lack of scientific information on R. matsumuranus leaves contributed to the investigation of the metabolomic profile and biological activity of this plant. In this study, metabolites of R. matsumuranus leaves in three stages (active growth, flowering, and fruiting) were characterised using high-performance liquid chromatography with photodiode array and electrospray ionisation triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS). In total, 63 compounds were identified, including gallic acid derivatives, hydroxycinnamates, catechins, procyanidins, flavonols, and ellagitannins. Lambertianin C (57.11 mg/g of dry weight, DW), miquelianin (39.63 mg/g DW), and kaempferol-3-O-glucuronide (31.18 mg/g DW) were the major compounds in R. matsumuranus leaves. As a result of the HPLC-PDA-based assay to determine the antioxidant activity, it was revealed that lambertianin A, sanguiin H6, lambertianin C, and sanguiin H11 were effective scavengers of free radicals (2,2-diphenyl-1-picrylhydrazyl, DPPH•) and possessed Fe2+-chelating activity. After an investigation of the phenolic content in infusions and decoctions obtained by extraction with water at different temperatures, it was revealed that a hot infusion (80 °C) is a phenolic-rich preparation of R. matsumuranus leaves. Our research suggests that R. matsumuranus leaves are a rich source of phenolic compounds with high antioxidant properties and that this could be a prospective plant for new functional products.

Metabolites of Prickly Rose: Chemodiversity and Digestive-Enzyme-Inhibiting Potential of Rosa acicularis and the Main Ellagitannin Rugosin D.

Prickly rose (Rosaacicularis Lindl.) is the most distributed rose species in the Northern Hemisphere, used by indigenous people for various food purposes. The lack of detailed information about the chemical composition of R. acicularis has led us to study the phytochemical composition and metabolic profile of prickly rose extracts using chromatographic techniques. Many groups of phenolic and non-phenolic compounds were quantified in the leaves, flowers, roots and fruits of R. acicularis. Phenolic compounds were the dominant phytochemicals in the aerial parts and roots of R. acicularis. A precise study by high-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection showed the presence of 123 compounds, among which ellagic acid derivatives, ellagitannins, gallotannins, catechins, catechin oligomers, hydroxycinnamates and flavonoid glycosides of kaempferol, quercetin and dihydroquercetin were all identified for the first time. The most abundant phenolic compounds were ellagitannins and flavonoid glycosides, with a maximal content of 70.04 mg/g in leaves and 66.72 mg/g in flowers, respectively, indicating the great ability of R. acicularis organs to accumulate phenolic compounds. By applying a standardized static, simulated gastrointestinal digestion method, we found the inhibitory potential of the leaf extract against digestive α-amylases. A pancreatic α-amylase activity-inhibiting assay coupled with HPLC microfractionation demonstrated high inhibition of enzyme activity by ellagitannin rugosin D, which was later confirmed by a microplate reaction with mammalian α-amylases and the simulated digestion method. This study clearly demonstrates that R. acicularis leaf extract and its main component, ellagitannin rugosin D, strongly inhibit digestive α-amylase, and may be a prospective antidiabetic agent.

Water-Soluble Melanoidin Pigment as a New Antioxidant Component of Fermented Willowherb Leaves (Epilobium angustifolium).

Willowherb (Epilobium angustifolium L., family Onagraceae) is a well-known food and medicinal plant used after fermentation as a source of beverages with high antioxidant potential. Despite this long history of use, only a few papers have described the chemical profile and bioactivity of fermented willowherb tea in general. To understand the basic metabolic differences of non-fermented and fermented E. angustifolium leaves, we used general chemical analysis, high-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection assay, and an isolation technique. As a result, the content of 14 chemical groups of compounds was compared in the two plant materials; 59 compounds were detected, including 36 new metabolites; and a new water-soluble phenolic polymer of melanoidin nature was isolated and characterized. The fundamental chemical shifts in fermented E. angustifolium leaves relate mainly to the decrease of ellagitannin content, while there is an increase of melanoidin percentage and saving of the antioxidant potential, despite the significant changes detected. The strong antioxidative properties of the new melanoidin were revealed in a series of in vitro bioassays, and a simulated gastrointestinal and colonic digestion model demonstrated the stability of melanoidin and its antioxidant activity. Finally, we concluded that the new melanoidin is a basic antioxidant of the fermented leaves of E. angustifolium, and it can be recommended for additional study as a promising food and medicinal antioxidant agent.

Sagan Dalya Tea, a New "Old" Probable Adaptogenic Drug: Metabolic Characterization and Bioactivity Potentials of Rhododendron adamsii Leaves.

Adams' rhododendron (Rhododendron adamsii Rehder) or Sagan Dalya tea is a famous Siberian evergreen medical plant of the Ericaceae family used in traditional medicines of Buryats, Yakuts, and Mongols as a tonic, stimulant, and adaptogenic drug. The high popularity of R. adamsii coupled with poor scientific knowledge prompted the addressing of gaps related to metabolic and biomedical data of Sagan Dalya tea. The application of solid-phase extraction and liquid chromatography-mass spectrometric techniques for the metabolomic study of R. adamsii leaf extracts resulted in the identification of more than 170 compounds, including carbohydrates, organic acids, simple phenol glycosides, triterpene glycosides, flavonoids, prenylated phenols, benzoic acid derivatives, hydroxycinnamates, dihydrochalcones, catechins, and procyanidins, most of which were identified for the first time in the plant. Extended surveys of the seasonal content of all detected compounds prove that specific metabolite variations reflect the bioactivity of R. adamsii extracts. Regarding in vitro methods, the expressed antioxidant potential of R. adamsii extracts was investigated via radical-scavenging, nitric oxide scavenging, and ferrous (II) ion chelating assays. The animal-based swimming to exhaustion test demonstrates the stimulating influence of R. adamsii extract on physical performance and endurance, concluding that the drug could act as an adaptogen. Thus, Sagan Dalya tea (R. adamsii) has confirmed its "old" application as a tonic remedy and requires further precise study as a novel adaptogenic plant.

Synanthropic Plants as an Underestimated Source of Bioactive Phytochemicals: A Case of Galeopsis bifida (Lamiaceae).

Hemp nettle (Galeopsis bifida Boenn.) is a synanthropic species of the Lamiaceae family that is widely distributed across Europe, Asia, and Siberia. Galeopsis bifida is deeply embedded in the ethnomedical tradition of Asian healers; however, this plant is still poorly characterized, both chemically and pharmacologically. To study Siberian populations of G. bifida, we used high-performance liquid chromatography with photodiode array and electrospray triple quadrupole mass detection for metabolic profiling. Ninety compounds were identified, including iridoid glycosides, phenylethanoid glycosides, hydroxycinnamates, and flavone glycosides, most of which were identified in G. bifida for the first time, while some phenolics were found to have potential chemotaxonomic significance in the Lamiaceae family and Galeopsis genus. An unequal quantitative distribution of the selected metabolites was observed within separate organs of the G. bifida plant, characterized by high accumulation of most compounds within the aerial part of the plant (leaves, flowers). Analysis of the content of specific chosen compounds within the leaves of different populations of G. bifida from Eastern Siberia revealed the existence of two chemical types based on metabolic specifics: the southern type accumulates flavone glucuronides, while the northern type tends to accumulate high levels of phenylpropanoids and acylated flavone glucosides. The first study of the bioactivity of G. bifida extract demonstrated that the herb has low toxicity in acute experiments and expresses antioxidant potential against free radicals in the form of DPPH˙, ABTS˙+, and superoxide radical, as well as high ferric reducing antioxidant power, oxygen radical absorbance capacity, and protective action in the carotene bleaching assay. In general, our results suggest the herb of G. bifida as a new, prospective synanthropic plant for medical application.