Biologically active flavonoid glycosides from Horwoodia dicksoniae Turrill

Abstract Background Artemisia splendens from the Asteraceae family is a new source of biologically active compounds. The current study investigated to evaluate antimicrobial and cytotoxicity activity of methanolic extracts and their fractions obtained from aerial parts by agar disk diffusion and MTT methods, respectively. The active fractions were subjected to preparative HPLC for isolating the pure compounds, which were structurally elucidated, by 1H and 13C NMR. Results The results showed that the methanolic extract and its 60% SPE fraction have the anti-proliferative activity on A549 cell line in comparison with the control group. Meanwhile, the methanolic extract and its 40% SPE fraction can inhibit the growth of Gram-positive strains as anti-microbial activity. The 60% SPE fraction also illustrated anti-proliferative activity on the HT-29 cell line compared to the control group. Chromatographic separations via preparative HPLC yielded 5 flavonoids and three flavonoid glycosides. Conclusion Based on the results it can be concluded that A. splendens as a potential source of cytotoxic and antimicrobial compounds can be used in pharmaceutics.

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Functional characterization of three flavonoid glycosyltransferases from Andrographis paniculata

Royal Society Open Science ◽

10.1098/rsos.190150 ◽

2019 ◽

Vol 6 (6) ◽

pp. 190150 ◽

Cited By ~ 4

Author(s):

Yuan Li ◽

Xin-Lin Li ◽

Chang-Jiang-Sheng Lai ◽

Rui-Shan Wang ◽

Li-Ping Kang ◽

...

Keyword(s):

Functional Characterization ◽

Biochemical Properties ◽

Flavonoid Glycoside ◽

Andrographis Paniculata ◽

Biologically Active ◽

Flavonoid Glycosides ◽

Asian Countries ◽

Pharmacological Activities ◽

Different Types

Andrographis paniculata is an important traditional medicinal herb in South and Southeast Asian countries with diverse pharmacological activities that contains various flavonoids and flavonoid glycosides. Glycosylation can transform aglycones into more stable, biologically active and structurally diverse glycosides. Here, we report three glycosyltransferases from the leaves of A. paniculata (ApUFGTs) that presented wide substrate spectra for flavonoid glycosylation and exhibited multi-site glycosylation on the substrate molecules. They acted on the 7-OH position of the A ring and were able to glycosylate several other different types of compounds. The biochemical properties and phylogenetic analysis of these glycosyltransferases were also investigated. This study provides a basis for further research on the cloning of genes involved in glycosylation from A. paniculata and offers opportunities for enhancing flavonoid glycoside production in heterologous hosts. These enzymes are expected to become effective tools for drug discovery and for the biosynthesis of derivatives via flavonoid glycosylation.

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Microbial Transformation of Flavonoids by Isaria fumosorosea ACCC 37814

Molecules ◽

10.3390/molecules24061028 ◽

2019 ◽

Vol 24 (6) ◽

pp. 1028 ◽

Cited By ~ 7

Author(s):

Fangmin Dou ◽

Zhi Wang ◽

Guiying Li ◽

Baoqing Dun

Keyword(s):

Natural Products ◽

Microbial Transformation ◽

Structural Diversity ◽

Biologically Active ◽

Biological Study ◽

Flavonoid Glycosides ◽

Spectroscopic Techniques ◽

Isaria Fumosorosea ◽

Stereo Selectivity ◽

Biological Methods

Glycosylation is an efficient strategy to modulate the solubility, stability, bioavailability and bioactivity of drug-like natural products. Biological methods, such as whole-cell biocatalyst, promise a simple but highly effective approach to glycosylate biologically active small molecules with remarkable regio- and stereo-selectivity. Herein, we use the entomopathogenic filamentous fungus Isaria fumosorosea ACCC 37814 to biotransform a panel of phenolic natural products, including flavonoids and anthraquinone, into their glycosides. Six new flavonoid (4-O-methyl)glucopyranosides are obtained and structurally characterized using high resolution mass and nuclear magnetic resonance spectroscopic techniques. These compounds further expand the structural diversity of flavonoid glycosides and may be used in biological study.

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Flavonoid Glycosides from Endemic Bulgarian Astragalus aitosensis (Ivanisch.)

Molecules ◽

10.3390/molecules24071419 ◽

2019 ◽

Vol 24 (7) ◽

pp. 1419 ◽

Cited By ~ 2

Author(s):

Hristo Vasilev ◽

Samir Ross ◽

Karel Šmejkal ◽

Petr Maršík ◽

Dagmar Jankovská ◽

...

Keyword(s):

Phenolic Compounds ◽

Structural Analysis ◽

Secondary Metabolites ◽

Chromatographic Separation ◽

2D Nmr ◽

Biologically Active ◽

Spectral Studies ◽

Flavonoid Glycosides ◽

Phenolic Components ◽

First Time

Astragalus is a very interesting plant genus, well-known for its content of flavonoids, triterpenes and polysaccharides. Its secondary metabolites are described as biologically active compounds showing several activities, e.g., immunomodulating, antibacterial, antiviral and hepatoprotective. This inspired us to analyze the Bulgarian endemic A. aitosensis (Ivanisch.) to obtain deeper information about its phenolic components. We used extensive chromatographic separation of A. aitosensis extract to obtain seven phenolic compounds (1–7), which were identified using combined LC-MS and NMR spectral studies. The 1D and 2D NMR analyses and HR-MS allowed us to resolve the structures of known compounds 5–7 as isorhamnetin-3-O-robinobioside, isorhamnetin-3-O-(2,6-di-O-α-rhamno-pyranosyl-β-galactopyranoside), and alangiflavoside, respectively, and further comparison of these spectral data with available literature helped us with structural analysis of newly described flavonoid glycosides 1–4. These were described in plant source for the first time.

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Analysis of Volatile Constituents of Ginkgo Leaf

Natural Product Communications ◽

10.1177/1934578x19857900 ◽

2019 ◽

Vol 14 (6) ◽

pp. 1934578X1985790

Author(s):

Szilvia Czigle ◽

Éva Héthelyi B ◽

Erzsébet Háznagy-Radnai ◽

Imre Máthé ◽

Jaroslav Tóth

Keyword(s):

Gas Chromatography ◽

Acid Methyl Ester ◽

Botanical Garden ◽

Biologically Active ◽

Gas Chromatography Mass Spectrometry ◽

Flavonoid Glycosides ◽

Active Components ◽

Volatile Constituents ◽

Vascular Insufficiency ◽

Ginkgo Leaf

Ginkgo biloba L. (Ginkgoaceae) is one of the oldest trees on earth. The medicinal use of its seeds and leaves has been a tradition for thousands of years. The standardized extract (known as EGb 761) contains several biologically active components, among them are terpenes and flavonoid glycosides that are responsible for the pharmacological activities of Ginkgonis folium. According to European Union herbal monographs (EUHM), the leaves of Ginkgo are recommended for the treatment of dementia, cerebral vascular insufficiency, and disorders of the peripheral circulation. The aim of our work was to analyze volatile constituents of Ginkgo leaf. Leaves of 3 Ginkgo trees were analyzed; 2 of which grow in the Medicinal Plants Garden (young trees A and B) and 1 at the Botanical Garden (old tree C) in Bratislava. The leaves were collected in 2014. The essential oil was isolated and quantified using hydrodistillation according to European Pharmacopoeia (Ph. Eur.) The volatile constituents of Ginkgonis folium were evaluated qualitatively and quantitatively using gas chromatography-mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID). We identified 16 constituents of the leaves of tree A, 18 in tree B, and 14 in tree C. The volatiles of the 3 trees differ in the respective amounts of monoterpenoids, hydrocarbons, fatty acids, and their methyl esters. The following constituents were identified in all of the 3 trees in largest percentage: hexahydrofarnesyl acetone (23.6%, 16.0%, and 27.7%), α-linolenic acid methyl ester (14.8%, 20.7%, and 15.1%), and pentacosane (22.2%, 22.4%, and 21.9%). Other identified compounds include the monoterpenes ( E)- α-ionone and ( E)- β-ionone.

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FEATURES OF THE COMPOSITION OF FLAVONOIDS IN THE CROWNED SAW-WORT (SERRATULA CORONATA L.S.L.) SIBERIA AND THE FAR EAST OF RUSSIA

chemistry of plant raw material ◽

10.14258/jcprm.2020026663 ◽

2020 ◽

pp. 171-179

Author(s):

Aleksey Viktorovich Myagchilov ◽

Larisa Ivanovna Sokolova ◽

Petr Grigor'yevich Gorovoy ◽

Aleksey Anatol'yevich Kechaikin

Keyword(s):

High Performance ◽

Far East ◽

Gradient Elution ◽

Extraction Methods ◽

Hplc Method ◽

Biologically Active ◽

Flavonoid Glycosides ◽

Far East Of Russia ◽

The Far East ◽

Serratula Coronata

One of the common plants in Siberia and the Far East of Russia, but little studied, is the crowned saw-wort (Serratula coronata L.s.l.) of the aster family (Asteraceae). The value of this plant is determined by its high content of phytoecdysteroids and flavonoids. From the aerial part (leaves, stems) of S. coronata L.s.l., growing in Siberia (Altai Region), by liquid extraction methods (70% ethanol) and preparative column chromatography on silica gel in the gradient elution mode with a mixture of solvents (carbon tetrachloride and ethyl alcohol), 2 flavonoids were isolated: quercetin-4'-O-β-D-glucopyranoside, luteolin-4'-O-β-D-glucopyranoside. Identification of the isolated compounds was carried out by UV-, NMR-13C-, 1H, 13C-HMBC-spectroscopy and electrospray mass spectrometry. The reverse-phase high-performance liquid chromatography (RP-HPLC) method was the first to investigate the qualitative composition and quantitative content of individual flavonoids in S. coronata L.s.l. plants growing in Altai and in the Primorsky region of the Russian Federation. The composition of flavonoid glycosides and the distribution of their aglycones in Siberian and Far Eastern plants differ and this can be considered a chemotaxonomic trait of the species S. coronata L.s.l. The spectrophotometry method was used to determine the sum of flavonoids in the aerial organs of crowned saw-wort growing in Altai and Primorsky region. The content of flavonoids in the leaves of the plant (6.7–8.3%) exceeds their content in the stems (0.5–0.9%). Crowned saw-wort sickle is a potential source of biologically active compounds of this class.

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Characterization of photosystem II with the atomic-force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130365 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1146-1147

Author(s):

Kathleen M. Marr ◽

Mary K. Lyon

Keyword(s):

Photosystem Ii ◽

Atomic Force Microscope ◽

Three Dimensional ◽

Biologically Active ◽

Atomic Force ◽

Freeze Etching ◽

Image Averaging ◽

Oxygen Evolving ◽

Averaging Techniques

Photosystem II (PSII) is different from all other reaction centers in that it splits water to evolve oxygen and hydrogen ions. This unique ability to evolve oxygen is partly due to three oxygen evolving polypeptides (OEPs) associated with the PSII complex. Freeze etching on grana derived insideout membranes revealed that the OEPs contribute to the observed tetrameric nature of the PSIl particle; when the OEPs are removed, a distinct dimer emerges. Thus, the surface of the PSII complex changes dramatically upon removal of these polypeptides. The atomic force microscope (AFM) is ideal for examining surface topography. The instrument provides a topographical view of individual PSII complexes, giving relatively high resolution three-dimensional information without image averaging techniques. In addition, the use of a fluid cell allows a biologically active sample to be maintained under fully hydrated and physiologically buffered conditions. The OEPs associated with PSII may be sequentially removed, thereby changing the surface of the complex by one polypeptide at a time.

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Depletion and Reconstitution of Active E. Coli Ribosomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116826 ◽

1975 ◽

Vol 33 ◽

pp. 640-641

Author(s):

M. Boublik ◽

W. Hellmann ◽

F. Jenkins

Keyword(s):

Protein Biosynthesis ◽

Large Subunit ◽

High Resolution Electron Microscopy ◽

Small Subunit ◽

Structure And Function ◽

Biologically Active ◽

Biological Macromolecules ◽

E Coli ◽

Resolution Electron ◽

And Function

Correlations between structure and function of biological macromolecules have been studied intensively for many years, mostly by indirect methods. High resolution electron microscopy is a unique tool which can provide such information directly by comparing the conformation of biopolymers in their biologically active and inactive state. We have correlated the structure and function of ribosomes, ribonucleoprotein particles which are the site of protein biosynthesis. 70S E. coli ribosomes, used in this experiment, are composed of two subunits - large (50S) and small (30S). The large subunit consists of 34 proteins and two different ribonucleic acid molecules. The small subunit contains 21 proteins and one RNA molecule. All proteins (with the exception of L7 and L12) are present in one copy per ribosome.This study deals with the changes in the fine structure of E. coli ribosomes depleted of proteins L7 and L12. These proteins are unique in many aspects.

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Fractionation of the Biologically Active Large Molecular Components of Human Gastric Content

Gastroenterology ◽

10.1016/s0016-5085(19)35388-0 ◽

1959 ◽

Vol 37 (4) ◽

pp. 439-444 ◽

Cited By ~ 1

Author(s):

Ranwel Caputto ◽

William O. Smith ◽

Jordan Tang ◽

Raul E. Trucco ◽

Walter Joel ◽

...

Keyword(s):

Gastric Content ◽

Biologically Active ◽

Molecular Components

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Bioavailability of naringenin chalcone in humans after ingestion of cherry tomatoes

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000574 ◽

2020 ◽

Vol 90 (5-6) ◽

pp. 411-416 ◽

Cited By ~ 2

Author(s):

Carina Kolot ◽

Ana Rodriguez-Mateos ◽

Rodrigo Feliciano ◽

Katharina Bottermann ◽

Wilhelm Stahl

Keyword(s):

Plasma Levels ◽

Average Concentration ◽

Biologically Active ◽

Thiol Groups ◽

Structural Element ◽

Active Molecule ◽

Reactive Center ◽

Average Maximum ◽

Alpha Beta ◽

Cherry Tomatoes

Abstract. Chalcones are a type of flavonoids characterized by an α-β unsaturated structural element which may react with thiol groups to activate pathways such as the Nrf2-Keap-1 system. Naringenin chalcone is abundant in the diet but little is known about its bioavailability. In this work, the bioavailability of naringenin chalcone from tomatoes was investigated in a group of healthy men (n=10). After ingestion of 600 grams of tomatoes providing a single dose of 17.3 mg naringenin chalcone, 0.2 mg of naringenin, and 195 mg naringin plasma levels of free and conjugated naringenin and naringenin chalcone (glucuronide and sulfate) were analyzed by UHPLC-QTOF-MS at 0.5, 1, 3, and 6 h post-consumption. Plasma levels of conjugated naringenin increased to about 12 nmol/L with a maximum at about 3 h. Concentrations of free naringenin hardly elevated above baseline. Plasma levels of free and conjugated naringenin chalcone significantly increased. A maximum of the conjugated chalcone was reached at about 3 h after ingestion with an average concentration of about 0.5 nmol/L. No free chalcone was detectable at baseline but low amounts of the unconjugated compound could be detected with an average maximum of 0.8 nmol/L at about 1 h after ingestion. The data demonstrate that naringenin chalcone is bioavailable in humans from cherry tomatoes as a dietary source. However, availability is poor and intramolecular cyclisation as well as extended metabolism likely contribute to the inactivation of the reactive alpha-beta unsaturated reactive center as well as the excretion of the biologically active molecule, respectively.

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