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For the first time, the composition and content of phenolic compounds in the leaves and inflorescences of Spiraea baldshuanica B. Fedtsch. was investigated. Research material was collected in June 2019 from a natural population in the Republic of Tajikistan. Phenolic compounds were studied in 40% water- ethanol extracts by the method of high-performance liquid chromatography (HPLC). The analytical HPLC system used consisted of an Agilent 1200 (USA) liquid chromatograph equipped with a diode array detector, an autosampler and a ChemStation system for collecting and processing chromatographic data. 15 and 11 compounds of phenolic nature were found in native extracts from inflorescences and leaves, respectively. Among them, the following substances were identified: chlorogenic and cinnamic acids, quercetin, kaempferol, hyperoside, isoquercitrin, avicularin and astragalin. The chromatographic profiles of leaves and inflorescences were found to be different. Such substances as isoquercitrin, avicularin, kaempferol were discovered in the inflorescences of S. baldshuanica , rather than in its leaves. Compared to the leaves, the concentration of all detected phenolic compounds was higher in the inflorescences under study. The major component in the inflorescences was astragalin (3.16 mg/g), whereas its concentration in the leaves was 5 times lower (0.60 mg/g). Flavonoid aglycones were obtained from the water-ethanol extracts of the leaves and inflorescences under study by acid hydrolysis using hydrochloric acid (1:1). The hydrolysates of extracts from the leaves and inflorescences of S . baldshuanica were found to contain 3 flavonoid aglycones: quercetin, kaempferol and isorhamnetin. By recalculating the concentration of aglycone for the corresponding glycoside, it was determined that quercetin glycosides prevails: 6.67 mg/g – in the inflorescences and 1.19 mg/g – in the leaves. S. baldshuanica differs significantly from other representatives of the Spiraea genus, section Calospira , in terms of the chromatographic profile of phenolic compounds contained in the leaves. This information serves as an additional argument for differentiating S. baldshuanica as a separate series of the Decumbentes group by morphological signs.

The bioactive chemicals in L. cuneata were investigated by repeated column chromatography and their effect on aldose reductase (AR), obtained from rat lenses, was examined. Results showed that the ethyl acetate and n-butanol fractions of L. cuneata exhibited potential inhibitory effect against AR with IC50 values of 0.57 and 0.49 μg/mL, respectively. Phytochemical analysis of these two fractions resulted in the isolation of five flavonoids namely, acacetin (1), afzelin (2), astragalin (3), kaempferol (4) and scutellarein 7-O-glucoside (5). The AR inhibitory effect of compounds 1-5 was explored; compounds 2, 3 and 5 showed potential AR-inhibitory effects with IC50 values of 2.20, 1.91 and 12.87 μM, respectively. Quantitative analysis of afzelin (2) and astragalin (3) in L. cuneata by high performance liquid chromatography with ultraviolet detection revealed its content to be 0.722–11.828 and 2.054–7.006 mg/g, respectively. Overall, this study showed that L. cuneata is rich in flavonoids with promising AR-inhibitory activities, which can be utilized for the development of natural therapies for treating and managing diabetic complications.

Helianthemum nummularium is a European shrub growing at high altitude where it copes with a high level of stress. It was found to be overexpressed in ungulates diets compared to more abundant surrounding plants. These elements combined with the fact that H. nummularium from the Alps has never been investigated prompted us to study the phytochemical composition of its aerial parts. The analysis of the polar extract allowed for the isolation of eight compounds: p-hydroxybenzoic acid, tiliroside, kaempferol, astragalin, quercetin, plantainoside B, quercetin-3-O-glucoside, and quercetin-3-O-glucuronide. We investigated the effect of the polar extract and isolated compounds on nuclear factor erythroid 2-related factor 2 transcription factor, which regulates the expression of a wide variety of cytoprotective genes. We found that the ethanolic extract activates the expression of nuclear factor erythroid 2-related factor 2 in a dose-dependent manner, whereas the pure compounds were much less active. The activation of the nuclear factor erythroid 2-related factor 2 pathway by the plant extract could pave the way for studies to promote healthy aging through protection of cells against oxidative stress. Moreover, the isolated compounds could be investigated alone or in combination in the perspective of making the link between the ungulateʼs preference for this plant and possible use of it for self-medication.

Inhibition of adipogenesis is crucial and is a key area of research to develop antiobesity drugs. In this study, 3-O-glucoside of kaempferol (astragalin) was isolated from Moringa oleifera leaves a...

The pharmacodynamic effect of longan leaves was attributed to various components, especially the flavonoids. In this paper, a new strategy of quantitative analysis of multicomponents by a single marker (QAMS) method was first established to synchronously determine 5 components (ethyl gallate (C1), astragalin (C2), quercetin (C3), luteolin (C4), and kaempferol (C5)) in Dimocarpus longan by ultra-performance liquid chromatography (UPLC) and high-performance liquid chromatography (HPLC). Quercetin (C3) was chosen as the internal reference. Relative correction factors (RCFs, ƒs/i) of the other 4 components were calculated by two correction methods (multipoint correction and slope correction) to effectuate QAMS. At the same time, the difference between the results measured by the QAMS and external standard methods was compared to verify the accuracy of QAMS. Within the linear range, the results showed that all ƒs/i values were obtained with good durability under diverse chromatographic conditions (RSD Dimocarpus longan collected from 10 producing areas by different chromatographic systems and quantitative methods were significantly correlated (Pearson’s r > 97.0%). The applicability and feasibility of the QAMS method established in this study were evaluated to be favorable for quality control of the leaves of Dimocarpus longan. As a new model of quality control, it can provide one more choice of multicomponent quality-control method in the absence of standard substances or instruments.

Neural stem cells (NSCs) exist in the central nervous system of adult animals and capable of self-replication. NSCs have two basic functions, namely the proliferation ability and the potential for multi-directional differentiation. In this study, based on the bioassay-guided fractionation, we aim to screen active components in Cuscuta chinensis to promote the proliferation of NSCs. CCK-8 assays were used as an active detection method to track the active components. On the basis of isolating active fraction and monomer compounds, the structures of these were identified by LC-MS and (1H, 13C) NMR. Moreover, active components were verified by pharmacodynamics and network pharmacology. The system solvent extraction method combined with the traditional isolation method were used to ensure that the fraction TSZE-EA-G6 of Cuscuta chinensis exhibited the highest activity. Seven chemical components were identified from the TSZE-EA-G6 fraction by UPLC-QE-Orbitrap-MS technology, which were 4-O-p-coumarinic acid, chlorogenic acid, 5-O-p-coumarinic acid, hyperoside, astragalin, isochlorogenic acid C, and quercetin-3-O-galactose-7-O-glucoside. Using different chromatographic techniques, five compounds were isolated in TSZE-EA-G6 and identified as kaempferol, kaempferol-3-O-glucoside (astragalin), quercetin-3-O-galactoside (hyperoside), chlorogenic acid, and sucrose. The activity study of these five compounds showed that the proliferation rate of kaempferol had the highest effects, at a certain concentration (25 μg/mL, 3.12 μg/mL), the proliferation rate could reach 87.44% and 59.59%, respectively. Furthermore, research results using network pharmacology techniques verified that kaempferol had an activity of promoting NSCs proliferation and the activity of flavonoid aglycones might be greater than that of flavonoid glycosides. In conclusion, this research shows that kaempferol is the active component in Cuscuta chinensis to promote the proliferation of NSCs.

Begonia semperflorens Link et Otto has been broadly raised up for ornamental purpose as well comestible blossom. As the reproductive structures of phanerogams, flowers contain various secondary metabolites and have many biological activities. Accordingly, we began the contrivance for isolation and analysis of flavonoids contained in B. semperflorens flowers. MeOH extraction of B. semperflorens followed solvent fractionation was prosecuted. Column chromatography of non-polar fraction gave four flavonoids using several resins. Identification of the flavonols were established as quercetin (1), kaempferol (2), astragalin (3), and isoquercetin (4) by interpreting a variety of spectral information. Quercetin (1) and kaempferol (2) inhibited NO production and protected against t-BHP-induced oxidative stress. Kaempferol (2) also protected cell death of glutamate-treated HT22. Quantitative analysis of flavonoid content in B. semperflorens flowers was also performed using HPLC experiment.

Kaempferol and astragalin are used as standards to assess the quality of Ginkgo biloba extract and Radix astragali, respectively, and possess numerous biological properties. In this study, we constructed a recombinant strain with a highly efficient biosynthetic pathway of kaempferol by screening key enzyme genes, designing a synthetic fusion enzyme and increasing the gene copy number. By optimizing conversion and fed-batch fermentation conditions, maximal kaempferol production reached 1184.2 ± 16.5 mg/L, which represents the highest yield of kaempferol from naringenin reported to date. Based on this result, glycosyltransferase (AtUGT78D2) and an efficient UDP-glucose synthesis pathway were introduced into the recombinant strain to produce astragalin, resulting in maximal astragalin production at 1738.5 ± 24.8 mg/L without kaempferol accumulation. The efficient synthesis pathway described in this study for kaempferol and astragalin biosynthesis can be widely used for flavonoid biosynthesis in Escherichia coli.

The Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in outbreak of global pandemic, fatal pneumonia in human referred as Coronavirus Disease-2019 (Covid-19). Ayurveda, the age old practice of treating human ailments in India, can be considered against SARS-CoV-2. Attempt was made to provide preliminary evidences for interaction of 35 phytochemicals from two plants (Phyllanthus amarus and Andrographis paniculata used in Ayurveda) with SARS-CoV-2 proteins (open & closed state S protein, 3CLpro, PLpro and RdRp) through in silico docking analysis. The nucleotide analogue remdesivir, being used in treatment of SARS-CoV-2, was used as a positive control. The results revealed that 18 phytochemicals from P. amarus and 14 phytochemicals from A. paniculata shown binding energy affinity/dock score

A study on some morphological characteristics and the set and levels of phenolic compounds was performed for the first time on Spiraea hypericifolia L. (Rosaceae Juss.) growing under natural conditions in the Novosibirsk region (four sites). Two phenotypic varieties of S. hypericifolia were identified. Twenty-three phenolic compounds were found in aqueous-ethanol extracts from S. hypericifolia leaves by high-performance liquid chromatography. Chlorogenic, p-hydroxybenzoic, and p-coumaric acids and quercetin, hyperoside, isoquercitrin, avicularin, rutin, and astragalin were identified among them. Hyperoside (6.7–20.5 mg/g) is the main phenolic compound in S. hypericifolia leaves. Flavonoid aglycones were prepared from the leaves by hydrochloric-acid hydrolysis of the aqueous-ethanol extracts (1:1). Three flavonol aglycones (quercetin, kaempferol, and isorhamnetin) were identified in the extract hydrolysates from S. hypericifolia leaves by chromatographic analysis. Quercetin glycosides proved to be predominant phenolic compounds in all the extract hydrolysates. A comparative analysis was performed on the levels of phenolic compounds in leaves among S. hypericifolia from the different sites and between the two varieties of S. hypericifolia. It was revealed that an increase in plant size by approximately twofold correlates with a decrease in concentrations of the identified flavonoids and phenolcarboxylic acids in S. hypericifolia leaves.

BackgroundAlthough traditional Chinese medicine is safe for the clinical treatment of angiogenesis, the in vivo intervention mechanism is diverse, complex, and largely unknown. Therefore, we aimed to explore the active ingredients of traditional Chinese medicine and their mechanisms for the treatment of angiogenesis.MethodsData on angiogenesis-related targets were collected from the GeneCards, Therapeutic Target Database, Online Mendelian Inheritance in Man, DrugBank, and DisGeNET databases. These were matched to related molecular compounds and ingredients in the traditional Chinese medicine system pharmacology platform. The data were integrated; based on the condition of Degree >1 and relevant literature, a target-compound network as well as compound-medicine and target-compound-medicine networks were constructed using Cytoscape. Molecular docking was used to predict the predominant binding combination of core targets and components.ResultsWe obtained a total of 79 targets for angiogenesis, and 41 targets were matched to 3839 compounds. Then, 110 compounds were selected owing to their high correlation with angiogenesis. Fifty-five combinations in the network were obtained by molecular docking, among which PTGS2-Astragalin (-9.18 kcal/mol), KDR-Astragalin (-7.94 kcal/mol), PTGS2-quercetin (-7.41 kcal/mol), and PTGS2-myricetin (-7.21 kcal/mol) were the top combinations. These results indicated that the selected potential core compounds may have good binding activity with the core targets. Eighty new combinations were obtained from the network, and the top combinations based on affinity were KDR-beta-carotene (-10.13 kcal/mol), MMP9-beta-Sitosterol (-8.04 kcal/mol), MMP9-Astragalin (-7.82 kcal/mol), and MMP9-Diosgenin (-7.51 kcal/mol). The core targets included PTGS2, KDR, VEGFA, and MMP9. The essential components identified were astragalin, kaempferol, myricetin, quercetin, and β-sitosterol. The crucial Chinese medicines identified included Polygoni Cuspidati Rhizoma et Radix, Morus alba Root Bark, and Forsythia Fructus.ConclusionsBy systematically analysing the essential ingredients of traditional Chinese medicine and their targets, it is possible to determine their potential mechanism of action in the treatment of pathological angiogenesis. Our study provides a basis for further research and development of new therapeutics for angiogenesis.

Drynariae Rhizome, widely distributed in southern China, was clinically used as a traditional treatment for cognitive disfunction, such as Alzheimer’s disease (AD). The aim of our work was to evaluate the AChE inhibition activities of extracts of Drynariae Rhizome and pure compounds using a bioguided fractionation procedure. The classical approach for screening potential AChE inhibitors was developed by Ellman. However, the background color of compounds or herb extracts remained uncertain and frequently interfered with the detection of the secondary reaction, thereby easily yielding false positive or false negative results. Here, a high-throughput assay monitoring the transformation of iodized choline from iodized acetylcholine catalyzed by AChE was established based on UPLC-MS/MS. The bioguided fractionation of the extract using this method resulted in the isolation of eight AChE inhibitory flavonoids, including naringenin, eriodictyol, kaempferol, luteolin, astragalin, luteolin-7-O-β-D-glucoside, naringin, and neoeriocitrin, with the IC50 values of 3.81 ± 0.21 μM, 7.19 ± 0.62 μM, 11.09 ± 1.02 μM, 17.26 ± 0.23 μM, 18.24 ± 2.33 μM, 17.13 ± 1.02 μM, 26.4 ± 1.17 μM, and 22.49 ± 1.25 μM. It is assumed that the identified flavonoids contribute to the AChE inhibition activity of Drynariae Rhizome. These results are in agreement with the traditional uses of Drynariae Rhizome for AD.

Column chromatographic separation of the MeOH extract from the roots of Dicentra spectabilis yielded fourteen compounds, menisdaurin (1), menisdaurilide (2), trans-N-pcoumaroyltyramine (3), trans-N-p-feruloyltyramine (4), 4-Oferuloylquinicacid (5), chlorogenic acid (6), 3-O-feruloylquinicacid (7), ferulic acid (8), protopine (9), Kaempferol 3,7-di-O-β-Dglucopyranoside (10), kaempferol 3-O-β-D-glucopyranosyl-7-O- α-L-rhamnopyranoside (11), α-rhamnoisorobin (12), astragalin (13), and nicotiflorin (14). Their structures were determined on the basis of NMR spectroscopic data. Among them, compound 1, 3- 8, and 10-14 isolated from this plant were reported for the first time. The isolated compounds (1-14) were tested for nitric oxide (NO) inhibitory activity on lipopolysaccharide-stimulated RAW 264.7 cells. Compound 3, 4 and 12 significantly inhibited NO production. Moreover, Compound 3 suppressed pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) in a dose- dependent manner. These data suggest that compound 3 possess anti-inflammatory activity and might be useful natural materials for development of anti-inflammatory agent.

Red Toon is a popular vegetable of favorable health benefits over Asia and Russia regions. In this study, isolation and identification of chemical constituents were performed to assess the quality of this functional food cultivated in various origins or harvested in different months. As a result, eight flavonol glycosides including rutin (I), myricitrin (II), quercetin-3-O-β-d-galactoranoside (III), quercetin-3-O-β-d-glucopyranose (IV), quercetin-3-O-α-l-arabinopyranoside (V), astragalin (VI), quercetin-3-O-α-l-rhamopyranoside (VII), and kaempferol-3-O-α-l-rhamopyranoside (VIII) were obtained. Among these, compounds III and V were isolated from Toona genus for the first time. Importantly, a rapid and convenient ultra-performance liquid chromatography (UPLC) method was developed to quantify the flavonol glycosides in Red Toon and validated for linearity, precision, stability, repeatability, and accuracy successively. In addition, it was found that total flavonoid glycosides (about 2.6%) in the food were ke...

Two phenolic acids (1 and 2) and seven flavonoids (3–9) were isolated from the aerial parts of Alyssum alyssoides (Brassicaceae). All these compounds (1–9) were isolated from this particular species for the first time. Their structures were identified, on the basis of MS and NMR spectra as: p-hydroxy-benzoic acid (1), 3-methoxy-4-hydroxybenzoic acid (vanillic acid) (2), kaempferol 3-O-β-D-glucopyranoside (astragalin) (3), kaempferol 3-O-(6″-α-L-rhamnopyranosyl)-β-D-glucopyranoside (nicotiflorin) (4), quercetin 3-O-β-D-glucopyranoside (isoquercetin) (5), quercetin 3-O-β-D-galactopyranoside (hyperoside) (6), isorhamnetin 3-O-β-D-glucopyranoside (7), isorhamnetin 3-O-β-D-galactopyranoside (8) and isorhamnetin 3-O-(6″-α-L-rhamnopyranosyl)-β-D-glucopyranoside (narcissin) (9). The chemotaxonomic significance of these compounds was summarized.

A new benzofuran derivative, pumiloside (1), together with seven known flavonoid glycosides, afzelin (2), astragalin (3), quercitrin (4), isoquercitrin (5), kaempferol 3-O-rutinoside (6), rutin (7) and kaempferol 3-O-sophoroside (8) were isolated from the leaves of Ficus pumila. Their structures were established by spectroscopic data and comparison with the literature values.

Site-specific accumulation of flavonoids in Apocyni Veneti Folium was determined by laser scanning confocal microscope (LSCM) and the localization of catechins also was observed via vanillin-HCl staining under the conventional optical microscope. The contents of five flavonoids in Apocyni Veneti Folium from different harvest times and growth parts were measured using HPLC method. LSCM observation showed that flavonoids are accumulated in cuticle of epidermal cells and vessel walls, especially in protoplasts and nucleolus of the collenchyma cells and the epidermal cells. Catechins are localized in the palisade parenchyma cells and vessel walls, particularly in the laticifers found in the phloem. On the basis of the difference of the maximal emission wavelength between quercetin and kaempferol derivatives which have fluorescence behavior by appropriate treatment, kaempferol and its derivatives are localized exclusively in the cuticle. Results showed that the content of astragalin in Apocyni Veneti Folium from different parts revealed the decreasing trend, while hyperin and isoquercitrin were higher in June and July analyzed by HPLC. In summary, the site-specific accumulation of flavonoids in Apocyni Veneti Folium can be determined by LSCM and vanillin-HCl staining. The contents of flavonoids in Apocyni Veneti Folium are correlated with harvest times and growth parts.

The ethanol extracts of Chimonanthus nitens Oliv. leaves were prepared sequentially by ethanol gradient elution and tested for their α-glucosidase inhibitory. The fraction of 50% ethanol eluate (EE) exhibited the notable inhibition with IC50 of 0.376mg/mL. Also, 50% EE was chemically characterized by liquid chromatography-mass spectrometry (LC-MS) analysis. Eight compounds including rutin (1), hyperin (2), isoquercitrin (3), luteoloside (4), astragalin (6), quercetin (13), naringenin (14), kaempferol (15) were identified by compared with standard substances as well as proper luteolin-5-O-glucoside (5), kaempferol-7-O-rhamnoside (9), 5,7,8-trihydroxy-2-methoxyl-flavone-7-O-glucoside (10), kaempferol-7-O-acetyl-galactoside (11). The experiments of ultra-filtration combined with liquid chromatography-mass spectrometry (UF-LC-MS) guided quercetin and kaempferol as the key factors for 50% EE showing highly inhibitory activity on α-glucosidase. Quercetin and kaempferol inhibited yeast α-glucosidase in a mixed-type manner with IC50 of 66.8 and 109μg/mL, respectively. These results would provide theoretical underpinning for the C. nitens Oliv. leaves ethanol extracts used as nutraceutical health supplement in the management of type 2 diabetes.

Daily changes in the composition and content of phenolic compounds in the aerial parts Potentilla fruticosa L., growing in culture of the Novosibirsk Region, using the method of high performance liquid chromatography (HPLC) was investigated. Six glycosides of flavonol (hyperoside, isoquercitrin, rutin, avicularin, quercitrin and astragalin), two aglycones (quercetin and kaempferol) and tannins (ellagic acid and its glycoside) were identified. Established that phenolic composition of P. fruticosa is the time of day remains constant. The highest total content of phenolic compounds in the leaves (28–29 mg/g of absolutely dry solid matter) and stems (4–4,5 mg/g) of P. fruticosa found in the evening and at night. In the flowers, in contrast, the maximum content of phenolic compounds was observed in the middle of the day (42 mg/g). The level of variability of the total content of phenolic compounds was evaluated as the lowest for leaves and flowers (СV = 10–11%). It was found a threefold increase in free aglycones - quercetin and kaempferol in the leaves with 3 to 6 o'clock in the morning on the background of reduction of the relevant glycosides in 1,5–2,5 times. Maximum accumulation of glycosides of quercetin and minimum content of free quercetin in flowers was observed at 12 o'clock. It is shown predominant accumulation of ellagic compounds quercitrin, component 10, hyperoside, isoquercitrin and rutin in the leaves in the evening and at night, in the flowers – in the middle of the day. The level of variability content of most of the individual components in the above-ground organs of P. fruticosa during the day was estimated as high (СV ≥ 21%)., Исследованы суточные изменения состава и содержания фенольных соединений в надземных органах Potentilla fruticosa при интродукции с использованием метода высокоэффективной жидкостной хроматографии (ВЭЖХ). Идентифицированы шесть флавонолгликозидов – гиперозид, изокверцитрин, рутин, авикулярин, кверцитрин и астрагалин, два агликона – кверцетин и кемпферол, а также эллаговые соединения – эллаговая кислота и ее гликозид. Состав фенольных соединений надземных органов P. fruticosa в течение суток не изменяется. Наибольшее суммарное содержание фенольных соединений в листьях (28–29 мг/г от абсолютно-сухой массы) и стеблях (4–4,5 мг/г) P. fruticosa обнаружено в вечернее и ночное время. В цветках, напротив, максимальное содержание фенольных соединений наблюдалось в середине дня (42 мг/г). Уровень вариабельности суммарного содержания фенольных соединений оценивался как низкий (СV = 10–11%). Установлено трехкратное повышение содержания свободных агликонов – кверцетина и кемпферола в листьях с 3 до 6 ч утра на фоне снижения содержания соответствующих флавонолгликозидов в 1,5–2,5 раза. В цветках максимальное накопление гликозидов кверцетина на фоне минимального содержания свободного кверцетина наблюдалось в 12 ч дня. Отмечено преимущественное накопление эллаговых соединений, кверцитрина, компонента 10, гиперозида, изокверцитрина и рутина в листьях в вечернее и ночное время, в цветках – в середине дня. Уровень вариабельности содержания большинства отдельных компонентов во всех органах P. fruticosa в течение суток оценивался как высокий (СV≥ 21%). Отмечен факт несовпадения динамики флавонолгликозидов и их агликонов.

Solanum cernuum is a medicinal plant widely distributed in south-east regions of Brazil and popularly used to treat several disorders. Despite their utilisation as a medicine, few studies on its chemical composition are reported. An efficient separation method for the ethyl acetate fraction was developed by high-performance countercurrent chromatography using n-butanol/chloroform/methanol/water (3:7:3:4, v/v/v/v) as the solvent system, affording five compounds (1–5) in one-step separation. A new cyclic guanidine alkaloid named cernidine (5) was obtained, besides four glycosylated flavonoids: afzelin (1), astragalin (2), kaempferol 3-O-α[apiofuranosyl-(1 → 2)]-α-rhamnopyranoside (3) and kaempferol 3-O-α[apiofuranosyl-(1→2)]-β-galactopyranoside (4). A further purification step afforded a mixture of trans- and cis-tiliroside (6–7). Countercurrent chromatography proved itself as a powerful tool for the isolation of similar compounds since compounds 1–2 and 3–4 possess little structural differences.

The composition and content of phenolic compounds in the leaves of Spiraea aemiliana Schneid. from 2 natural populations growing on the Island of Kunashir were studied by HPLC. The chromatographic profiles of S. aemiliana and closely related species S. betulifolia Pall and S. beauverdiana Schneid. were compared. Nineteen compounds were detected in 40 % water-ethanol extracts from the leaves of S. aemiliana. Of these, сhlorogenic, p-сoumaric and cinnamic acids, quercetin, kaempferol, hyperoside, isoquercitrin rutin, avicularin, astragalin and dihydroquercetin (taxifolin) were identified. A specific compound in the leaves of S. aemiliana is isoquercitrin, not identified in other closely related species. The chromatographic profiles of S. aemiliana and S. betulifolia are generally very similar. This is additional evidence of the opinion of scientists about the taxonomic rank of S. aemiliana as a subspecies, variation, or form of S. betulifolia. S. aemiliana (the sum of phenolic compounds varies from 16.4 to 23.,88 mg/g) is more similar to S. beauverdiana in the quantitative content of phenolic compounds. Leaves of S. aemiliana contain a lot of hyperoside (up to 9.50 mg/g), which is almost twice as much as that of S. beauverdiana (up to 4.3 mg/g) and 6 times that of S. betulifolia (up to 1.55 mg/g). The revealed difference in the hyperoside content between the three Spiraea taxa is statistically significant. &nbsp, Методом ВЭЖХ изучены состав и содержание фенольных соединений в листьях Spiraea aemiliana Schneid. из 2 природных популяций, произрастающих на острове Кунашир. Проведено сравнение хроматографических профилей S. aemiliana и близкородственных видов S. betulifolia Pall. и S. beauverdiana Schneid. В 40 % водно-этанольных экстрактах из листьев S. aemiliana выявлено 19 соединений. Из них идентифицированы хлорогеновая, n-кумаровая и коричная кислоты, кверцетин, кемпферол, гиперозид, изокверцитрин, рутин, авикулярин, астрагалин и дигидрокверцетин. Специфичным соединением в листьях S. aemiliana является изокверцитрин, не идентифицированный у других близких видов. Хроматографические профили S. aemiliana и S. betulifolia в целом очень сходны. Это является дополнительным доказательством мнения учёных о таксономическом ранге S. aemiliana как подвида, вариации или формы S. betulifolia. По количественному содержанию фенольных соединений S. aemiliana (сумма фенольных соединений варьирует от 16,4 до 23,88 мг/г) более сходна с S. beauverdiana. Листья S. aemiliana содержат много гиперозида (до 9,50 мг/г), что практически в два раза больше, чем у S. beauverdiana (до 4,3 мг/г) и в 6 раз у S. betulifolia (до 1,55 мг/г). Выявленная разница в содержании гиперозида между тремя таксонами Spiraea статистически достоверна.

The changes of phenolic compounds from the freeze-dried, hot-air dried, roasted and steamed mulberry (Morus alba L.) leaves during the in vitro digestion were investigated. Caffeoylquinic acids, quercitrin glycosides and kaempferol glycosides were the main compounds. After simulated gastrointestinal digestion, the bioaccessibility of phenolics was much higher in roasted samples than those in hot-air, dried and steamed samples. Approximately 50%–80% of the bioaccessible phenolics were dialyzable depending on the different processing methods. The freeze-dried samples contributed to the highest amount of bioaccessible phenolics, followed by hot-air dried and roasted ones. All the initial phenolics degraded rapidly and were not detected after 24 h of faecal fermentation, except that at 0.5 h the amount of isoquercitrin and astragalin were increased by 156.48% and 177.44%, respectively. Consequently, quercetin, kaempferol, dihydrocaffeic acid, 3-(4-hydroxyphenyl) propionic acid and 3-methoxyphenyl-acetic acid were formed at different time. Transformation pathways for phenolics in the faecal fermentation were proposed.

The active components of Malus pumila flowers on antioxidant and tyrosinase activity were investigated with the method of spectrum-effect relationship and knock-out. Some compounds were identified by UPLC-MS/MS method. The chemical fingerprints were established by HPLC and the activity of antioxidant and tyrosinase were assayed in vitro. Chromatographic peaks P34, P35, P39, P44, P45 and P49 were identified as phloridzin, hyperoside, astragalin, afzelin, quercetin and kaempferol by UPLC-MS/MS method. Hyperoside and kaempferol were identified in M. pumila flowers for the first time. When the concentration was 1 g/mL of sample (equivalent to raw material), the scavenging capacity of P35 (hyperoside) on DPPH free radicals were consistent with the spectrum-effect relationship. The scavenging capacity of P34 (phloridzin) and P45 (quercetin) on ABTS free radicals were consistent with the spectrum-effect relationship. The activation effect of P45 (quercetin) on tyrosinase was consistent with the spectrum-effect relationship. The inhibitory effect of P34 (phloridzin), P35 (hyperoside) on tyrosinase were consistent with the spectrum-effect relationship.

The Naoxinqing (NXQ) tablet is a standardised proprietary herbal product containing an extract of persimmon leaves (Diospyros kaki) for the management of cardio- and cerebrovascular diseases. Although previous reports suggested that the efficacy of NXQ is at least partly mediated by its anti-oxidative property, the anti-oxidative effect of the major components of NXQ has not been studied systematically. For quality control purposes, only analytical methods limited to 3 marker analytes have been reported, the extent to which the other components affect efficacy has not been explored. In this study, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC MS/MS) method for the identification of seven analytes (kaempferol-3-O-glucoside (astragalin), quercetin-3-O-galactoside (hypericin), quercetin-3-O-glucoside (isoquercitin), kaempferol, 3,4-dihydroxybenzoic acid (protocatechuic acid), and furan-2-carboxylic acid (pyromucic acid) and quercetin) in the NXQ. This is the first method reported and validated for the quantification of the seven major secondary metabolites in NXQ. The results for the quantified analytes were then compared in 15 different batches of NXQ. The variation observed in the seven components highlights the need to quantify key bioactive components to ensure product consistency. Radical scavenging activity and abundance was used to rank the analytes. The anti-oxidative effects of NXQ were examined using cultured human vascular endothelial cells (EA.hy926). Corrected 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) activity results revealed that quercetin and kaempferol have the strongest anti-oxidant capacity in the extract. Both quercetin and kaempferol significantly inhibited the hydrogen peroxide (H2O2)-induced EA.hy926 cell injury and intracellular reactive oxygen species (ROS) generation. In conclusion, we established and validated an UPLC-MS/MC method for the analysis of major bioactive components in the NXQ and demonstrated that its anti-oxidative property may play a critical role in cerebrovascular protection.

This study developed a method for simultaneous determination of 13 elements of Semen Cuscutae (quercitrin, quercetin, hyperoside, caffeic acid, chlorogenic acid, luteolin, apigenin, kaempferol, isoquercitrin, cryptochlorogenic acid, isorhamnetin-3-O-glucoside, astragalin, and rutin) in rat plasma using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in the negative MRM mode. The analytes were analyzed with CORTECS®C18 column (4.6 × 150 mm, 2.7 μm) with mobile phases consisting of 0.1% formic acid in water (A) and acetonitrile (B). The intra- and interday precision of the target compounds were expressed as relative standard deviation (RSD) in the range of 0.5%–10.4%, and the accuracy of the target compounds was expressed as relative error (RE) not exceeding ±14.5% for all analytes. In the meantime, the extraction recovery of the target compounds in plasma samples ranged from 87.4% to 106.2% and matrix effect from 81.0% to 115.5%. The established method was successfully accomplished for the pharmacokinetic study of the analytes in rat plasma samples following oral administration of Semen Cuscutae extract, and the pharmacokinetic parameters of seven compounds were obtained.

Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanums) is a kind of traditional folk medicinal plant which has been used widely in China for its antivirus, antitumor, and other clinical effects. In this study, ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry (UPLC-Q-Exactive/MS) was utilized to analyze the chemical constituents of T. hemsleyanums. Fifty-one constituents were clarified, including flavonoids, anthraquinones, esters, fatty acids, phenols, and catechins. In the subsequent quantitative analysis, the contents of ten compounds of rutin, kaempferol, astragalin, quercitrin, quercetin, vitexin-rhamnoside, isorhamnetin, vitexin, emodin-8-O-β-D-glucoside, and isoquercetin in 18 batches of T. hemsleyanums collected from different places of cultivation were determined. Meanwhile, anti-influenza virus bioactivity in vitro of the above samples was detected with Gaussia Luciferase viral titer assay. It was found that the antiviral bioactivity varied from batches to batches in accordance with content difference of the chemical constituents in T. hemsleyanums. Correlation analysis was performed with SPSS software for the association between LC-MS chemometrics and bioactivity of influenza virus inhibition, and 8 constituents of flavonoids showed positive correlation coefficient, which may provide a valuable clue for searching potential antiviral components in T. hemsleyanums.

SmltD is an ATP-dependent ligase that catalyzes the condensation of UDP-MurNAc- l -Ala and l -Glu to form UDP-MurNAc- l -Ala- l -Glu, in the newly discovered peptidoglycan biosynthesis pathway of a Gram-negative multiple-drug-resistant pathogen, Stenotrophomonas maltophilia. Phytochemical investigation of the 70% ethanol extract from Woodfordia fruticosa flowers collected in Myanmar led to the identification of anti-SmltD active flavonoids, kaempferol 3-O-(6′′-galloyl)-β- d -glucopyranoside (1), astragalin (2), and juglalin (3). Among them, 1 showed the most potent SmltD inhibitory activity. An enzyme steady-state kinetic study revealed that 1 exerted competitive inhibition with respect to ATP. The results of this study provided an attractive foundation for the further development of novel inhibitors of SmltD.

Background and purpose: Paracetamol is the most implicated xenobiotic in inducing hepatotoxicity. Our study aimed to determine the impact of some kaempferol glycosides isolated from the leaves of Cedrela odorata L. on paracetamol hepatotoxicity. Experimental approach: The methanolic extract of dried leaves of C. odorata L . was subjected to the combination of spectroscopic methods ( 1 H and 13 CNMR). Six kaempferol glycosides were isolated: kaempferol-3- O -b-D-glycopyranoside (astragalin), kaempferol-3- O -b-L-rhamnopyranoside, kaempferol-3- O -b-D-rutinoside, kaempferide-3- O -b-D-rutinoside, kaempferide-3- O -b-Drutinosyl-7- O -b-D-rhamnopyranoside, and kaempferol-3- O -b-D- rutinosyl-7- O -α-D-arabinopyranoside. Fifty-four female Swiss Albino mice were divided randomly into 9 groups including (1) control negative (1 mL/kg saline; IP), (2) control positive (paracetamol 300 mg/kg; IP), (3) silymarin 50 mg/kg (IP). Animals of groups 4-9 were injected with 6 different samples of isolated compounds at 100 mg/kg (IP). One h later, groups 3-9 were injected with paracetamol (300 mg/kg IP). Two h later, tissue samples were taken from all animals to assess nitrotyrosine, c-Jun N-terminal protein kinase (c-JNK), Raf -1kinase, and oxidative stress biomarkers viz. reduced glutathione (GSH) and malondialdehyde (MDA). Findings/Results: Isolated glycosides had a prominent anti-apoptotic effect via inhibition of c-JNK and Raf-1 kinase. They also exerted a powerful antioxidant effect by modulating the oxidative stress induced by paracetamol via increasing GSH, reducing MDA and nitrotyrosine concentrations compared to positive control. The glycoside (1) showed a better effect than silymarin (standard) in ameliorating the formation of nitrotyrosine, Raf-1 kinase, c-JNK, and GSH. C onclusion and implication: Kaempferol glycosides isolated for the first time from C. odorata L. leaves exerted antioxidant and antiapoptotic effects via amelioration of oxidative stress and inhibition of Raf/ MAPK pathway.

Astragalin (kaempferol 3-O-glucoside) is used as a standard to assess the quality of Radix astragali and has exhibited a number of biological properties. In this work, we screened several UDP-dependent glycosyltransferases (UGT) for their potential as efficient biocatalysts for astragalin synthesis. The highest astragalin production with 285 mg/L was detected in the recombinant strain expressing UGT from Arabidopis thaliana (AtUGT78D2). To further improve astragalin production, an efficient UDP-glucose synthesis pathway was reconstructed in the recombinant strain by introducing sucrose permease, sucrose phosphorylase, and uridylyltransferase. On the basis of those results, a recombinant strain, BL21-II, was constructed to produce astragalin. By optimizing conversion conditions, astragalin production was increased from 570 to 1708 mg/L. The production was scaled up using a fed-batch fermentation, and maximal astragalin production was 3600 mg/L, with a specific productivity of 150 mg/L/h after 24 h incubation and a corresponding molar conversion of 91.9%, the highest yield reported to date.

Phytochemical investigation of Lespedeza cuneata led to the isolation of seventeen compounds including three steroids (β-sitosterol 1, β-sitosterol-6′-linolenoyl-3-O-β-d-glucopyranoside 3, and β-sitosterol glucoside 13), nine flavonoids (quercetin 4, kaempferol 5, isovitexin 8, hirsutrin 9, nicotiflorin 10, vitexin 11, astragalin 12, trifolin 14, and isorhamnetin 17), two phenolics (benzyl-β-d-glucopyranoside 7 and homovanillyl alcohol 16), one carotenoid (loroxanthin 2), one lignin (7R,8S–dihydrodehydrodiconiferyl alcohol 15), and one hexose (pinitol 6) on the basis of their spectroscopic data. Among these compounds, 2, 3, 7, 15 and 16 were reported for the first time from the genus Lespedeza. The taxonomic significance of these isolated compounds was also summarized.

The aim of this study was to compare the flavonoids compositions, content and antioxidant activities of Hawk tea from six botanical origins for screening the most suitable botanical origins. The main flavonoids of Hawk teas from Litsea coreana Levl. var. lanuginose were identified, and six high contents of individual flavonoids (hyperin, isoquercitrin, quercitrin, astragalin, quercetin and kaempferol) were quantitative and comparative analysis. Moreover the potential antioxidant capacity of Hawk tea was measured by using in vitro antioxidant assays. The above experimental data were all used for the principal component analysis. The statistical results showed that the extracts from Machilus chuanchienensis S. Lee and L. coreana Levl. var. lanuginose appeared closely positioned in the positive regions, indicated the higher flavonoids and antioxidant activity compared with other species. Thus, they were temporarily considered as good sources of Hawk tea.

Introduction Impatiens glandulifera Royle (Balsaminaceae) is an annual herb from the Himalaya region, currently widespread along European river systems and one of the most important neophyte invading plants in Germany. Exploring the effects of allelopathic plant chemicals is important for the understanding of its ecological impacts in the process of suppression of indigenous plant species. Objective To investigate the chemical composition of Impatiens glandulifera flowers (IGFs) using high performance countercurrent chromatography (HPCCC). Methods The flowers of Impatiens glandulifera were manually separated and extracted with ethanol. LC-ESI-MS/MS was used to characterise the crude extract of IGF. The various flavonoids detected were isolated by HPCCC using of methyl tert-butyl ether–acetonitrile–water (2:2:3, v/v/v). The combination of the data provided by preparative ESI-MS/MS metabolite profiling, LC-ESI-MS/MS, UV-vis and 1D/2D-NMR spectroscopic analysis was used to elucidate the structures of the isolated compounds. Results HPCCC runs led to the direct isolation of pure dihydromyricetin (ampelopsin), eriodictyol-7-O-glucoside, kaempferol-3-O-glucoside (astragalin) and kaempferol-3-O-6ʺ-malonyl-glucoside, as well as the pre-purification of kaempferol-3-O-rhamno-rhamnosyldiglucoside, quercetin-3-O-galactoside (hyperoside), quercetin and kaempferol in a single step. Conclusion This is the first report on the flavonoid composition of the species Impatiens glandulifera. The developed protocol was successfully used to isolate the main flavonoids from the crude extract of IGFs. This combined HPCCC and HPLC procedure could be applied to the fast fractionation and recovery of flavonoid derivatives of other plant extracts. Copyright © 2016 John Wiley & Sons, Ltd.

At least 22 phenolic compounds were identified in aqueous-ethanol extracts from Sorbaria pallasii (G. Don fil.) Pojark. leaves and at least 28 in its inflorescences by High-Performance Liquid Chromatography. Two acids (chlorogenic and p-hydroxybenzoic) and five flavonols (hyperoside, isoquercitrin, quercitrin, kaempferol, and astragalin) were identified among them. Flavonoid aglycones were obtained from the leaves and inflorescences by hydrochloric-acid hydrolysis of the aqueous-ethanol extracts (1:1). Three flavonol aglycones (quercetin, kaempferol, and isorhamnetin) were identified in the extract hydrolysates from S. pallasii above-ground organs through chromatographic analysis. Additionally, a flavone aglycone (luteolin) was found in the extract hydrolysates from the leaves. Kaempferol glycosides are predominant phenolic compounds in S. pallasii inflorescences, and quercetin glycosides in its leaves.

Natural products, an infinite treasure of bioactive chemical entities, persist as an inexhaustible resource for discovery of drugs. This review article intends to emphasize on one of the naturally occurring flavonoids, astragalin (kaempferol 3-glucoside), which is a bioactive constituent of various traditional medicinal plants such as Cuscuta chinensis. This multifaceted compound is well known for its diversified pharmacological applications such as anti-inflammatory, antioxidant, neuroprotective, cardioprotective, antiobesity, antiosteoporotic, anticancer, antiulcer, and antidiabetic properties. It carries out the aforementioned activities by the regulation and modulation of various molecular targets such as transcription factors (NF-κB, TNF-α, and TGF-β1), enzymes (iNOS, COX-2, PGE2, MMP-1, MMP-3, MIP-1α, COX-2, PGE-2, HK2, AChe, SOD, DRP-1, DDH, PLCγ1, and GPX), kinases (JNK, MAPK, Akt, ERK, SAPK, IκBα, PI3K, and PKCβ2), cell adhesion proteins (E-cadherin, vimentin PAR-2, and NCam), apoptotic and antiapoptotic proteins (Beclin-1, Bcl-2, Bax, Bcl-xL, cytochrome c, LC3A/B, caspase-3, caspase-9, procaspase-3, procaspase-8, and IgE), and inflammatory cytokines (SOCS-3, SOCS-5, IL-1β, IL-4, IL-6, IL-8, IL-13, MCP-1, CXCL-1, CXCL-2, and IFN-γ). Although researchers have reported multiple pharmacological applications of astragalin in various diseased conditions, further experimental investigations are still mandatory to fully understand its mechanism of action. It is contemplated that astragalin could be subjected to structural optimization to ameliorate its chemical accessibility, to optimize its absorption profiles, and to synthesize its more effective analogues which will ultimately lead towards potent drug candidates.

Semen Cuscutae, which mainly consisted of flavonoids, is a traditional Chinese herbal medicine and used for nourishing the liver and kidneys. The aim of this study was to develop a sensitive and selective UPLC-MS/MS method for simultaneous separation and determination of six main active renoprotective components of Hyperoside, Astragalin, Isoquercitrin, Quercitrin, Quercetin, and Kaempferol from Semen Cuscutae in rat plasma, and to reveal the pharmacokinetic differences between normal and kidney deficient rats. The validated method has been successfully applied to comparing pharmacokinetic profiles of the six analytes in rat plasma. The results indicated that there was significant difference in pharmacokinetic parameters of the six analytes between two groups, while absorptions in kidney deficient group were significantly lower than those in normal group. This study would be helpful for evaluating the Semen Cuscutae as renoprotective drug candidates for pre-clinical and clinical research.

As a traditional Chinese medicine, Drynariae rhizoma (Kunze ex Mett.) J. Sm. has been used to treat osteoporosis and bone resorption for 2500 years. Based on the previous study and literature references, flavonoids were proved to be the most abundant and main active compounds of Drynariae rhizoma for osteoporosis treatment. In order to make good and rational use of Drynariae rhizoma in future, a rapid, sensitive, and selective ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS) method was developed to investigate the pharmacokinetics of eight main flavonoids in rat plasma after oral administration of the Drynariae rhizoma extract, including neoeriocitrin, luteolin-7-O-β-D-glucoside, astragalin, naringin, eriodictyol, luteolin, naringenin, and kaempferol. Plasma samples’ pretreatment involved a solid-phase extraction column. The separation was performed on an ACQUITY UPLCTM BEH C18 column with a gradient mobile-phase system of acetonitrile and 1% acetic acid in water. The detection was performed using a triple quadrupole tandem mass spectrometer equipped with an electrospray ionization interface (ESI) by multiple reaction monitoring (MRM) in the positive ion mode. All calibration curves exhibited good linearity (r2 > 0.9990) over the measured ranges. The intraday and interday precisions (RSD) were within 13.87%, and the accuracy (RE) ranged from −14.57% to −0.25% at three quality control levels. Extraction recovery, matrix effect, and stability were satisfactory. The pharmacokinetic characteristics of the eight flavonoids of interest were clearly elucidated.

Ethnopharmacological relevance: Meadowsweet (Filipendula ulmaria (L.) Maxim.) and dropwort (Filipendula vulgaris Moench) are herbaceous perennials employed in folk medicine for their antirheumatic, antipyretic and antiulcer properties. Aim of the study: To assess ethnomedicinal claims through investigation of antioxidant, anti-inflammatory and gastroprotective effects of F. ulmaria and F. vulgaris lyophilized flower infusions (LFIs) as well as the F. vulgaris isolated flavonoids spiraeoside, kaempferol 4'-O-glucoside, astragalin 2'-O-gallate, mixture of hyperoside 2'-O-gallate and isoquercitrin 2'-O-gallate, and a tannin tellimagrandin IL Materials and methods: Free radical scavenging activity of the tested samples was determined by examining their ability to neutralize DPPH and OH radicals in vitro, whereas reducing properties were assessed in Ferric Reducing Antioxidant Power (FRAP) assay. Anti-inflammatory activity was studied ex vivo in human platelets by monitoring the effect on eicosanoid biosynthesis.. Gastroprotective action was estimated in animal model of acute gastric injury induced by ethanol. Results: LFIs and spiraeoside exerted activities comparable to those of positive control in DPPH-radical scavenging and FRAP antioxidant assays, whereas notable hydroxyl radical scavenging ability was demonstrated only for spiraeoside (IC50 = 5.1 mu g/mL). Among tested samples, astragalin 2 ''-O-gallate (IC50 = 141.1 mu g/mL) and spiraeoside (IC50 = 4.69 mu g/mL) the most markedly inhibited production of pro -inflammatory prostaglandin E-2 and 12(S)-hydroxy-(5Z,8Z,10E,14Z)-eicosatetraenoic acid in human platelets, respectively. Examination of LFIs (100-300 mg/kg, p.o.) gastroprotective action in rats revealed their capacity to preserve mucosal integrity. In addition, spiraeoside (50 mg/kg, p.o.) and tellimagrandin II (40 mg/kg, p.o.) showed ulcer preventive ability. Conclusion: Current study supports documented traditional use of investigated herbs and indicates that flavonoid and tannin components are partially responsible for the demonstrated pharmacological activities. This is peer-reviewed version of the following article: Samardžić, S.; Arsenijević, J.; Božić, D.; Milenković, M.; Tešević, V.; Maksimović, Z. Antioxidant, Anti-Inflammatory and Gastroprotective Activity of Filipendula Ulmaria (L.) Maxim. and Filipendula Vulgaris Moench. Journal of Ethnopharmacology 2018, 213, 132–137. [https://doi.org/10.1016/j.jep.2017.11.013] Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3154]

Flavonoids compounds such as kaempferol (1), kaempferol-3-O-β-D-glucopyranoside or astragalin (2) and kaempferol-3-O-α-L-rhamnoside or afzelin (3) have been isolated from the fresh leaves of Kalanchoe tomentosa (Crassulaceae). The chemical structure of isolated compounds 1-3 were identified by spectroscopic evidences and comparison with those compound previously reported. Compounds 1-3 showed cytotoxic activity against P-388 murine leukimia cells with IC50 values of 51.8, > 100 and 3.32 µg/mL, respectively.

Rubus chingii Hu has been used as a functional food for a long time. This work was aimed to identify the anti-inflammatory ingredients from R. chingii by an activity-guided isolation. The ethanol extracts of R. chingii were partitioned into petroleum ether, ethyl acetate, butanol and water fractions, and the ethyl acetate fraction exhibited excellent anti-inflammatory activity. Five flavonoid glycosides were isolated from the ethyl acetate fraction based on anti-inflammatory assay-guided purification, which were identified as quercitrin, hyperoside, tiliroside, astragalin and kaempferol 3-rutinoside. The inhibitory effects of extract fractions and compounds on NO production in LPS-stimulated macrophage RAW 264.7 cells were evaluated. The five flavonoid glycosides displayed different degrees of anti-inflammatory activity, among which tiliroside showed stronger activity than others. Further analysis showed that the anti-inflammatory activity of tiliroside might be exerted through inhibiting the activation of ERK and JNK to decrease NO and pro-inflammatory cytokines (TNF-α, iNOS and IL-6) production.

The calyx of Fragaria ananassa (Rosaceae) has not been investigated for its chemical constituents and biological activity. This study focused on the isolation of active metabolites from the calyx of this plant. Compounds from F. ananassa calyx were extracted in 80 % aqueous MeOH and the concentrated extract was successively partitioned into EtOAc, n-BuOH, and H2O fractions. Repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies afforded six purified flavonoids. On the basis of spectroscopic methods, including 1H, 13C nuclear magnetic resonance spectrometry (NMR), DEPT, and 2D NMR (gCOSY, gHSQC, gHMBC), the flavonoids were identified as kaempferol (1), astragalin (2), quercetin (3), isoquercitrin (4), sexangularetin (5), and sinensin (6). All the flavonoids were isolated for the first time from the F. ananassa calyx in this study. The flavonoids were evaluated for radical-scavenging capacity 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid ammonium salt), 2,2-diphenyl-1-picrylhydrazyl, and oxygen radical absorbance capacity methods. In conclusion, quercetin (3) consistently showed the highest ABTS, DPPH, and ORAC radical-scavenging activities compared with the other isolated flavonoids.

One new proline-containing flavonol glycoside, namely kaempferol-3-O-methyl-7-O-β-D-glucopyranosyl-8-(1-methyleneproline)-4'-O-β-D-glucopyranoside (1), together with 15 known flavonoids, 3-O-methylkaempferol (2), 3-O-methylquercetin (3), quercetin (4), kaempferol (5), apigenin (6), rhamnazin (7), astragalin (8), alquds (9), quercitrin (10), rutin (11), isoquercitrin (12), apigetrin (13), myricitrin (14), hesperidin (15) and calycosin-7-O-β-D-glucopyranoside (16) were isolated from the aerial parts of Caragana leucophloea Pojark. (Leguminosae). Their structures were determined on the basis of spectroscopic analyses and by comparison with literature data. Compounds 2-4 revealed a strong antimicrobial activity with minimum inhibitory concentration values of 12.5-150 μg/mL and median inhibitory concentration (IC50) values of 7.42-76.61 μg/mL. Compounds 3, 4, 6-8, 10-12 and 14 showed strong antioxidant activity. Compounds 2-7 exhibited moderate antinematodal activity on Caenorhabditis elegans with IC50 values of 40.51-68.05 μg/mL.

Quercetin is a dietary flavonoid which has an effect on inflammation, angiogenesis and vascular inflammation. In several other flavonoids (e.g. kaempferol, astragalin, alpinetin, baicalein, indirubin), anti-inflammatory mechanism was proven by using mice mastitis model. The aim of the current study was pilot analysis of quercetin tolerability and its impact on somatic cells count (SCC) after multiple intramammary treatment on dairy cows with clinical mastitis. Based on SCC and clinical investigation, 9 dairy cows with clinical mastitis of one quarter were selected for the pilot study. Baseline analysis (hematology, TNFα, SCC) was performed every 24h among all cows three days before the first dose (B1-B3). After the baseline monitoring (B1-B3) eight days treatment (D1-D8) was performed with a high and low dose. Selected blood parameters were analyzed. Starting from D1 to D8, a decrease of SCC in relation to baseline was characterized by declining trend. The presented results allowed the confirmation of the significant influence of quercetin on the reduction of SCC in mastitis in dairy cows after 8days of therapy.