Inhibitory Effect of Flavonoid Glycosides from Chlorophytum comosum on Nasopharyngeal Carcinoma 5-8F Cells and Its Mechanism

[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs.

Two New Flavonoid Glycosides from Chrysanthemum morifolium

Two new flavonoid glycosides were isolated from the flowering heads of Chrysanthemum morifolium. Their structures were determined to be luteolin 4＇-methoxy-7- O-（6＂-O-acetyl）-β-D-glucopyranoside （1） and acacetin 7-O-（3＂-O-acetyl）-β-D-glucopyranoside （2） by means of 1H and 13C NMR spectroscopic analysis, including 2D NMR technique.

New Flavonoid Glycoside from Thalictrum przewalskii

A new flavonoid glycoside, 5, 7-dihydroxy-4'-methoxyflavonoid 7-Q-[6-O-(4-O-acetyl-alpha-L-rhamnosyl)-3-O-beta-D-glucosyl]-6-O-acetyl-beta-D-glucoside was isolated from Thalictrum przewalskii. Its structure was determined on basis of spectroscopic evidences.

Simultaneous determination of seven alkaloids and two flavonoid glycosides in Wuzhuyu decoction by RP-HPLC-DAD

A reversed-phase high-performance liquid chromatography （RP-HPLC） method with diode array detector was established to simultaneously determine nine bioactive compounds in Wuzhuyu decoction, namely dehydroevodiamine, isorhanmetin-7-O- rutinoside, 10-hydroxyrutaecarpine, diosmetin-7-O-13-D-glucopyranoside, evodiamine, rutaecarpine, 1-metbyl-2-n-nonyl-4（1H） quinolone, evocarpine, and dihydroevocarpine. The RP-HPLC assay was performed on a reversed-phase Cl8 column with a gradient elution. The mobile phases consisted of methanol and water containing 1% （v/v） acetic acid. The flow rate was 1.0 mL/min and the detection wavelength was set at 300 nm. All calibration curves showed good linearity （r2〉0.9941） within test ranges. The results of intra-day precision, inter-day precision, and accuracy were satisfactory. The overall recoveries were in the range of 90.13%-102.48%. The method was successfully applied to quantify nine bioactive compounds in six samples. Baseline resolution for all nine major compounds was achieved. This method could be used as a suitable quality control assay for Wuzhuyu decoction.

New flavan and unusual chalcone glycosides from Drypetes parvifolia

Two new compounds 7-hydroxy-5-O-（β-D-glucopyranoside） flavan （1） and （Z）-4＇,6＇-dihydroxy-2＇-O-（β-D-glucopyranoside） chalcone （2）, along with eight known compounds, were isolated from the stem bark of Drypetes parvifolia （Euphorbiaceae）. Their structures were established on the basis of spectroscopic analysis and chemical evidence.

Constituents from Ranunculus sieboldii Miq.

Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate chemical constituents, and their structures wereelucidated by extensive spectroscopic methods (UV, IR, MS, ~1H NMR, ^(13)C NMR) including 2D NMR(COSY, HMQC, HMBC, NOESY) techniques and by direct comparing spectral data with those reported inliterature. Results Five flavonoid glycosides named apigenin-4'-O-α-L-rhamnopyranoside (1),apigenin-7-O-β-D-glucopyranosyl-4'-O-α-L-rhamnopyranoside (2), apigenin-8-C-α-L-arabinopyranoside(3), apigenin-8-C-β-D-ga-lactopyranoside (4) , tricin-7-O-β-D-glucopyranoside (5), together withtricin (6), luteolin (7), scopoletin (8), esculetin (9), scoparone (10), ferulic acid (11),protocatechuic acid (12) , and tematolide (13) were isolated from the 95% etha-nolic extract of itswhole plant, and their cytotoxic activities were preliminarily tested. Conclusion Compounds 1-12were obtained from this genus and compound 13 from this species for the first time. Furthermore,compound 1 was for the first time isolated from nature while the ^(13)C NMR data of compounds 2 and3 are reported for the first time. The bioassay revealed that compound 1 was active against BEL-7407and A549 cell lines (IC_(45) 43, 77 μg·mL^(-1)), 8 and 10 showed inhibitory activities on KB celllines (IC_(50) 78, 44 μg·mL^(-1)) and HL-60 cell lines (Ic_(50) 85, 85 μg·mL^(-1)), while 7exerted moderate cytotoxic activities on KB, BFL-7407, A549 and HL-60 cell lines with their IC_(50)being 51, 55, 44 and 10 μg·mL^(-1) , respectively.

The First Total Synthesis of Isoliquiritin

A first total synthesis of isoliquiritin was accomplished starting from p-hydroxybenzaldehyde and 2,4-dihydroxyacetylphenone. The key step is condensation reaction. In synthetic process need not protect the hydroxy group of reacting substance.

New In Vitro Studies on the Bioprofile of Genista tenera Antihyperglycemic Extract

The inhibition of a-glucosidase and glucose-6-phosphatase,two enzymes involved in the carbohydrate metabolism,is an important target to control glycaemia on individuals with type 2 diabetes.In this work we report for the first time the inhibition of both enzymes by the antihyperglycemic n-butanol extract from Genista tenera(Fabaceae).This extract decreased a-glucosidase and glucose-6-phosphatase activities to 0.97 and 80.25%,respectively,being more effective than acarbose,and phlorizin,the positive controls,which reduced enzymes activities only to 17.39 and 96.06%.Once inflammation and oxidative stress are related to diabetic impairments,the anti-inflammatory activity of the extract was also evaluated,through its inhibitory activity over COX-1 enzyme(47.5%inhibition).Moreover,after induction of oxidative stress by UV radiation,the viability of irradiated rat liver hepatoma cells exposed to the extract was significantly higher(67.82%)than that promoted by ascorbic acid,the positive control(45.05%).In addition,the stability of the extract under gastrointestinal conditions was evaluated by HPLC–DAD-ESI–MS/MS.Flavonoid diglycosides were identified as the main constituents of the extract,and no alterations in the chemical composition nor in the antioxidant activity were observed after in vitro digestion with artificial gastric and pancreatic juices.

Structural Elucidation and HPLC Analysis of Six Flavone Glycosides from Artemisiafrigida Willd.

An investigation of the EtOAc-soluble fraction from the aerial parts ofArtemisiafrigida Willd.（A. frigida） led to the isolation of three new flavonoid glycosides together with three known compounds. Their structures were elucidated by spectral experiments. At the same time, high-performance liquid chromatographic（HPLC） method was used for the simultaneous determination of the six flavonoid glycosides from the aerial parts ofA. frigida. The separation by gradient elution was performed on a Hypersil ODS-2 column（250 mm×4.6 mm, 5 μm） at 30℃ with acetonitrile and water as the mobile phase, and monitored by absorbance at 276 nm. The parameters of linearity, precision, accuracy and specificity of the method were evaluated. The recovery of the method is 96.50%--98.01%, and linearity（r〉0.9992） was obtained for all the flavonoid glycosides. A high degree of specificity as well as repeatability and reproducibility（relative standard deviation values less than 2.0%） were also achieved. This assay was applied to the determination of six flavonoid glycosides in ten samples. The results indicate that the developed assay method was rapid, accurate, reliable and could be readily utilized as a quantitative analysis method for A. frigida.

Flavonoids isolated from Sinopodophylli Fructus and their bioactivities against human breast cancer cells

Four prenylated flavonoids compounds 1-4,named sinopodophyllines A-D,and a flavonoid glycoside(compound 13),sinopodophylliside A,together with 19 known compounds(compounds 5-12 and 14-24) were isolated from the fruits of Sinopodophyllum hexandrum.The structures of new compounds were elucidated by extensive spectroscopic analysis,including HRESIMS,1D and 2D NMR.Compounds 1-6,9-11,and 14-17 were tested for their cytotoxicity against human breast-cancer T47 D,MCF-7 and MDA-MB-231 cells in vitro,and compounds 2,5,6,10 and 11 showed significant cytotoxicity(IC50 values < 10 μmol·L^(-1))against T47 D cells.

Determination of flavonoids,polyphenols and antioxidant activity of Tephrosia purpurea:a seasonal study

OBJECTIVE： Tephrosia purpurea （Linn.） Pers. is widely used in traditional medicine to treat liver disorders, febrile attacks, enlargement and obstruction of liver, spleen, and kidney. In the present study investigations were carried out to determine the seasonal impact on the content of flavonoid glycosides and on antioxidant activities so as to identify the optimal time of harvesting. METHODS： The plant materials were collected in different seasons during 2013-2014. Air-dried, powdered plant materials were extracted with 95% ethanol and ethanol：water （1：1 ） by ultrasound-assisted extraction process. Their chemical composition in terms of total polyphenol and flavonoid contents （TPCs and TFCs） was determined using modified colorimetric Folin-Ciocalteu method and aluminum chloride colorimetric assay respectively. To determine the in vitro antioxidant activity, diphenyl-picryl hydrazyl （DPPH） radical-scavenging assay and total antioxidant capacity by phosphomolybdate antioxidant assay were carried out. High-performance liquid chromatography （HPLC）/photo-diode array （PDA） analysis was used to quantify the flavonoid glycosides in the samples collected in different seasons. Correlation studies were also carried out between antioxidant activities and TPCs. RESULTS： The highest TPC and TFC were found to be in the 95% ethanolic extract of the August sample and the lowest in the 50% hydro-alcoholic extract of the plant sample collected in winter season. It was observed that in both the assays used to determine the antioxidant activity, the 95% ethanolic extracts in all the seasons showed a higher activity than their respective 50% hydro- alcoholic extracts with an increase in activity as we go from cold to hot to rainy seasons. Based on correlation analysis, DPPH radical-scavenging activities as well as the spectrophotometrically measured phosphomolybdenum complex were also strongly correlated with TPC of the extracts, The most abundant flavonoid glycoside was quercetin-3-O-rhamnoglucoside in all the seasons. The content of all flavonoids was observed highest in the 95% ethanolic extract of the plant collected in August （TP-3）. The 50% hydro-alcoholic extract of the plant collected in December （TP-6） showed the lowest amount of flavonoids and antioxidant activity. CONCLUSION： The findings of this study confirmed that the metabolism and production of flavonoids in T. purpurea are vigorously affected by seasonal factors. Significant differences were observed in the TPC, TFC and flavonoid glycoside composition in the 95% ethanolic as well as 50% hydro-alcoholic extracts of 7： purpurea collected in different seasons. Since the 95% ethanolic extract of the August sample （TP-3）, which also happens to be its flowering season, exhibited the highest TPC, TFC and antioxidant activities in both DPPH and phosphomolybdate assays as well as contained the highest content of allflavonoids, it could be recommended as the optimal season of harvesting T. purpurea with respect to its pharmaceutically important constituents, i.e., flavonoids.

Four new phenolic glycosides from Baoyuan decoction

Four new phenolic glycosides,including two flavonoid glycosides(1 and 2) and two lignan glycosides(3 and 4),were isolated from the traditional Chinese medicine formula,Baoyuan decoction.Their structures were established by detailed analysis of the NMR and HR-ESI-MS spectroscopic data and their absolute configurations were determined by the experimental electronic circular dichroism data as well as chemical methods.Furthermore,the sources of the four new compounds were determined by the UPLC-Qtrap-MS method,which proved that 1 and 2 are originated from Glycyrrhiza uralensis,and 3 and4 are from Cinnamomum cassia.

Virtual Evaluation on Activities of Flavonoids from Scutellaria baicalensis

Objective To explore the investigation method of complicated and profound traditional Chinese herbal medicine,the potential action mechanisms of flavonoids from Scutellaria baicalensis were studied by docking calculation.Methods In total,eight flavonoids(aglycones and their glicosides) from S.baicalensis were selected as ligands.The crystalline structures of targets related to common diseases were used as the receptors for calculation.The calculations were conducted with Schrdinger software package.The grading standard of selectivity was developed according to G-score between ligands and receptors.Results Twenty-six pharmacologic actions have been reported.Among all effects in literature,nine of them can be deduced from the docking calculation of aglycone.From glycosides with grade ++,25 reported effects can be estimated by calculation.Apparently,the target selectivity of aglycones and their glycosides are different form the virtual evaluation.The virtual evaluation results of glycosides were closer to the reported effects.Conclusion Our proposed virtual evaluation method seems an effective way to investigate the complicated system of traditional Chinese herbal medicine.It suggests that aglycones may be effective as the form of glucoside in vivo,and metabolism is a very important factor for virtual evaluation.

Apigenin-7-O-β-D-glycoside isolation from the highly copper-tolerant plant Elsholtzia splendens

Elsholtzia splendens （Lamiaceae） is a copper-tolerant plant species growing on copper deposits in the south of China. Chromatographic separation of n-BuOH extracts from the flowering aerial biomass afforded apigenin- 7-O-β-D-glycoside, using macroporous resin, SephadexTM LH-20 gel, polyamide resin as well as preparative high- performance liquid chromatography （P-HPLC） columns. Chemical structure was elucidated using HPLC/ESI-MS （electrospray ionization-mass spectrometry）, Fourier transform infrared （FTIR）, and 1D- and 2D-nuclear magnetic resonance （NMR）. Apigenin-7-O-β-D-glycoside could be the post-harvesting product from E. splendens biomass.