Total phenolic content,ferric reducing and DPPH scavenging activity of Arum dioscoridis

Arum dioscoridis, locally called ‘Gavur pancari’, is a wild plant the leaves of which have been used as vegetable and for preparing special soup which has a sour taste. This study was set up to determine in vitro antioxidant activities and total phenolic and flavonoid contents of different extracts of A. dioscoridis. Free radical scavenging activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing activity with different concentrations of ethanol, methanol, acetone and water extracts of the plant leaves. Total phenolic and flavonoid contents were widely variable depending on solvents. Ethanol and methanol extractions of the plant material showed better performances with respect to both phenolic and flavonoid contents, respectively. The highest phenolic and flavonoid contents of ethanol and methanol extracts were 100.890 mg/g GAE and 72.643 mg/g QE, respectively. The lower DPPH scavenging and ferric reducing activities were determined in comparison with previous reports and standard synthetic chemicals.     

Simultaneous Determination of Five Phenolic Compounds in Dried Flowers by LC Using DAD Combined Electrochemical Detection

A simple, sensitive and accurate method for the simultaneous separation and determination of apigenin and four phenolic acids including chlorogenic acid, caffeic acid, p-coumaric acid and ferulic acid in four dried flowers by high performance liquid chromatography with electrochemical detection (ECD) and diode array detection (DAD) has been established. The detection limits of caffeic acid, p-coumaric acid and ferulic acid obtained with ECD were 3, 1 and 4 ng mL^?1, and LOD of apigenin and chlorogenic acid obtained with DAD were 1 × 10^?2 and 6 × 10^?2 μg mL^?1. The detection and quantification limits of three phenolic compounds obtained with ECD were two to ninefold greater than those obtained with DAD. As electrochemically inactive compounds, apigenin and chlorogenic acid were detected by DAD. All calibration curves showed good linearity (r ≥ 0.9992) within the test ranges. The recoveries ranged from 95.3 to 101.4% (RSD ≤ 2.9%). This approach could provide scientific evidence for comprehensive evaluation about the effect of the medicine and ensure nutrient status of dried flowers.     

Analysis of plasma migration components in Patrinia villosa (Thunb.) Juss. effective parts by UPLC–Q-TOF–MS

Patrinia villosa (Thunb.) Juss. (PVJ) is described as pungent, bitter and slightly cold in Chinese medicine, and is associated with the large intestine, stomach and liver meridians. The preliminary experiments of our research team proved that PVJ total flavonoids have excellent inhibitory effects on liver cancer cells. The present experiment uses the UPLC–Q-TOF–MS technology and serum pharmacochemistry methods to analyze the chemical components in vitro and in vivo of PVJ antiliver tumors. A total of 14 chemical components were identified in the total flavonoids extract of PVJ, and it is mainly composed of flavonoids, flavonones, flavonols and phenolic acids. At the same time, seven prototypical components and seven metabolic components were detected in the drug-containing plasma. Hydrocaffeate and scutellarein are the phase I metabolites of caffeic acid and scutellarin, respectively. Sulfated apigenin, sulfated luteolin, sulfated kaempferol and methylated kaempferol are the II phase metabolites of apigenin, luteolin, kaempferol, respectively. The experiment provides a reference for the research and development of antitumor drug candidates, and provides a basis for revealing the bioactive components of PVJ and the antitumor mechanism.     

A new caffeic acid tetramer from the Dracocephalum moldavica L.

A new caffeic acid tetramer compound, named (+) methyl rabdosiin (4), together with seven known caffeic acid multimers (1–3, 5–8) and one caffeic acid monomer (9), were isolated from the aerial parts of Dracocephalum moldavica L. The structures of these compounds were assigned on the basis of 1D and 2D NMR spectroscopic and mass spectrometry analyses. The protective effects of compounds 2–4 against hydrogen peroxide (H₂O₂)-induced apoptosis were evaluated in primary cardiomyocytes of SD neonatal rats in vitro by the MTT method. Three compounds exhibited potent protective activities at 12.5 μg/mL.     

Flavonoid Glycosides from Terminalia catappa L.

Under the inhibition of Cu⁺²‐induced LDL oxidation‐guided fractionation, two new flavone glycosides with galloyl substitution were isolated from the dried fallen leaves of Terminalia catappa L. Their structures were established as apigenin 6‐C‐(2″‐O‐galloyl)‐β‐D‐glucopyranoside ( 1 ) and apigenin 8‐C‐(2″‐O‐galloyl)‐β‐D‐glucopyranoside ( 2 ), together with four known flavone glycosides, isovitexin, vitexin, isoorientin, and rutin, on the basis of spectroscopic method. Compounds 1 and 2 showed significant antioxidative effects. Their IC₅₀ were 2.1 and 4.5 μM, respectively.     

New cytotoxic flavonoids from aerial parts of Platycladus orientalis L.

Abstract

Investigation of Platycladus orientalis yielded five flavonoids, including aglycone flavone 1 (apigenin), flavone glycoside 2 (apigenin 7-O-β-D-glucopyranoside), new gernaylated flavone glycoside 3 (apigenin 8-gernayl-4′-O-α-gluco pyranoside) and two new pernylated flavonoid glycosides 4 & 5 (apigenin 8-pernyl-4′-glucopyranosyl-7-O-α-glucopyranoside and apigenin 5-pernyl-7-glucopyranosyl-4′-O-β-D-glucopyranoside). Their structures were elucidated on the basis of spectroscopic evidence. The cytotoxicity of compounds 1–5 were tested against Lung adenocarcinoma (A549), human hepatocellular liver carcinoma (HepG2), human breast carcinoma (MCF-7) cell lines and mouse fibroblast cell line NIH/3T3 as normal cells. This assay gave spot on structure activity relationship which, showed that cytotoxicity of compounds (1) and (2) against three cell lines was weak as IC₅₀?>?15. Compounds (4) and (5) had moderate cytotoxic and no toxic effect on normal cell. Compound (3) showed high cytotoxic activity against tested three cell lines with no toxic effect of normal cells.

     

Chemical compositions and antibacterial activity of extracts obtained from the inflorescences of Cirsium canum (L.) all

The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacillus cereus and Bacillus subtilis belonging to opportunistic microorganisms.     

Chemical constituents and allelopathic activity of Machaerium eriocarpum Benth.

Abstract

The analysis by HPLC-PDA of the hydroalcoholic extract of the leaves of M. eriocarpum together with the injection of the fractions containing the already identified metabolites allowed the detection of at least 5 flavonoids, of which two are derived from apigenin and three from luteolin. After isolating larger amounts of isovitexin (I), assays were performed to evaluate the allelopathic activity together with the crude extract. The results show that the initial inhibition indexes were very similar to those observed in the treatments with F17 (Fraction enriched in isovitexin) and F18 (isovitexin), mainly in the concentrations of 500 and 1000?mg L^?1. The index of the number of lateral roots, an increase of the inhibitory effect is observed with the increase of the concentration of M. eriocarpum extract.     

The High Performance Liquid Chromatography and Detection of Phospholipids and Triglycerides. III. Response of the Differential Refractive Index and Ultraviolet Absorption Detector

Abstract

A liquid chromatographic differential refractive index detector (RI) and an ultraviolet absorption (at 195 nm) detector (UV) were studied for detection of triglyceride (TG) and phospholipid (PL) molecular species. It was found that the log UV/RI detector response ratio was linearly related to the log of the number of conjugated double bonds (degree of unsaturation) of the lipid in a predictable fashion, indicating the usefulness of the combination of both detectors in TG and PL analysis. The detection limit of the RI detector for TG and PL was found to be 5 × 10 ^?7 M or as sensitive as the UV detector for saturated TG and PL.     

Determination of Phenolic Acids and Flavones in Lonicera japonica Thumb. by Capillary Electrophoresis with Electrochemical Detection

Capillary electrophoresis with electrochemical detection (CE‐ED) was employed to analyze active ingredients of Lonicera japonica Thumb., an important crude herb frequently used in Chinese medicines. Hyperoside, chlorogenic acid, luteolin and caffeic acid are the major important active ingredients. Operating in a wall‐jet configuration, a 300 μm diameter carbon‐disk electrode was used as the working electrode, which exhibits a good response at +0.90 V (vs. saturated calomel electrode) for four analytes. Under the optimum conditions, the analytes were baseline separated within 20 min in a 50 mmol L^?1 borax buffer (pH 8.7). Notably, excellent linearity was obtained over two orders of magnitude with detection limits (S/N=3) ranging from 0.1 to 0.5 mg L^?1 for all the analytes. This method was successfully used in the analysis of Lonicera japonica Thumb. with relative simple extraction procedures, and the assay results were satisfactory.     

Identification and in vitro antioxidant activities of phenolic compounds isolated from Cynoglossum cheirifolium L.

In an extensive search for bioactive compounds from plant sources, the quantitative and qualitative characterisation of the compounds present in Cynoglossum cheirifolium extracts was studied. Total phenolic and flavonoid contents were determined by spectrophotometric techniques. In vitro antioxidant and radical scavenging profiling was determined through DPPH^? scavenging activity and Ferric reducing antioxidant power (FRAP). Our study showed that leaves produce more phenolic compounds, followed by flowering aerial part. The butanolic fraction obtained from leaves extract exhibited the highest total phenolics (78.65 ± 3.58 mg GAE/g DW) and flavonoids (22.15 ± 4.66 mg CE/g DW). In contrast, this fraction displayed the highest DPPH^? scavenging ability with IC₅₀ values of 0.06 ± 0.003 mg/mL. The RP-HPLC-PDA analysis of phenolic compounds from leaves of C. cheirifolium lets to identify: rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid, syringic acid, sinapic acid and rutin. The obtained results indicate that this plant represent a valuable source of natural antioxidants.     

Antioxidant activity of some Turkish medicinal plants

DPPH, superoxide and nitric oxide radical scavenging activities and total phenolic content (TPC) of some less known plants, distributed in Burdur-Antalya provinces and consumed both as food and for the medicine, Asplenium ceterach L. (golden herb), Valeriana dioscoridis Sm. (valerian), Doronicum orientale Hoffm. (tiger herb), Cota pestalozzae (Boiss.) Boiss. (camomile), Eremurus spectabilis M. Bieb. (foxtail lily), Asphodeline lutea (L.) Rchb. (asphodel) and Smyrnium connatum Boiss. and Kotschy (hemlock) were investigated. As a result, the highest 2,2-diphenyl-1-picril hydrazyl (DPPH) radical scavenging activity was determined in C. pestalozzae extract (IC₅₀ = 18.66 μg mL^? 1), the highest superoxide and nitric oxide radical scavenging activity was determined in A. ceterach extract (IC₅₀ = 145.17 and 372.03 μg mL^? 1). The highest TPC was determined in A. ceterach extract (59,26 μg mL^? 1) as gallic acid equivalent. Further bioactivity and phytochemistry studies on these plants may enlighten new drug discovery researches.     

Determination of Phenolic Compounds and the Antioxidant Capacity of Ximenia parviflora Benth. var. parviflora (Olacaceae) Fruit by High-Performance Liquid Chromatography with Diode Array Detection

The total phenolic and flavonoid content, phenolic composition, and in vitro antioxidant capacity of ethanolic extracts of Ximenia parviflora Benth. var. parviflora fruits collected at Zinaparo, Michoacan (in central Mexico) were determined. Fruit extracts present a high scavenging activity of 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis[3-ethylbenzothiazoline-6-sulfonic acid] radicals (71.49?±?0.11% and 85.00?±?1.29% inhibition, respectively). The four phenolic compounds identified in fruit extracts by high-performance liquid chromatography with diode array detection were gallic acid, chlorogenic acid, caffeic acid, and quercetin. X. parviflora fruits may be used as a starting material for the extraction of high value antioxidant phenolic compounds with potential applications in the pharmaceutical and dietary supplement industries.     

Constituents of the Whole Herb of Clinoponium laxiflorum

The isolation and identification of twenty‐two components (including one new compound) from the whole herb of Clinoponium laxiflorum (Hay) Matsum (Labiatae) are described. Their structures were determined on the basis of spectral and chemical transformation. One new compound is methyl rosmarinate. The other twenty‐one compounds include three steroids (α‐spinasterol, α‐spinasteryl‐3‐O‐β‐D‐glucopyranoside, and β‐sitosteryl‐3‐O‐β‐glucopyranoside), three triterpenes (oleanolic acid, ursolic acid, and betulinic acid), nine flavonoids (didymin, apigenin‐7‐O‐β‐glucopyranoside, luteolin‐7‐O‐β‐glucopyranoside, isosakuranetin, narigenin, apigenin, luteolin, narirutin, and hesperidin), three lignolic acids (rosmarinic acid, 3‐(3,4‐dihydroxyphenyl)lactic acid, and caffeic acid), and three phenols (4‐hydroxybenzaldehyde, 3,4‐dihydroxybenzaldehyde, and 3,4‐dihydroxybenzoic acid).     

Identification and screening of active components from Ziziphora clinopodioides Lam. in regulating autophagy

This study investigated the flavonoid constituents of a traditional Chinese medical plant Ziziphora clinopodioides Lam. by using ultra-performance liquid chromatography coupled with quadruple time-of-flight mass spectrometry and screened the active components in regulating autophagy.Normal rat kidney (NRK) cells transfected with green fluorescent protein- microtubule-associated protein 1 light Chain 3(GFP-LC3) were treated with Z. clinopodioides flavonoids and its chemical compositions. After 4 h of treatment, the auto-phagy spot aggregation in NRK cells was photographed and observed by laser scanning confocal microscopy. The following 10 flavonoid components of Z. clinopodioides were identified: baicalein(1), quercetin(2), hyperoside(3), quercetin3-O-β-d-glucopyranoside(4), apigenin(5), kaempferol(6), chrysin(7), diosimin(8), linarin(9) and rutin(10). Among these flavonoids, chrysin, apigenin and quercetin were identified as the active principles in activating autophagy. This research may provide a reference for further developing and utilizing Z. clinopodioides.     

Antioxidant activities and quali-quantitative analysis of different Smallanthus sonchifolius [(Poepp. and Endl.) H. Robinson] landrace extracts

Five landraces of Smallanthus sonchifolius [(Poepp. and Endl.) H. Robinson], known as yacon, were investigated in total phenolic content, antioxidant activity and chemical composition of ethanol extracts (EEs) and decoction extracts (DEs). The results demonstrated that DEs are rich in phenolic acids as caffeic acid, while the EEs show an higher amount of flavonoids, as luteolin 3′,7-O-diglucoside and luteolin 7-O-glucoside. These flavonoid glycosides were identified for the first time in yacon extracts, together with apigenin and luteolin. The phytochemical profile explains the different antioxidant activities shown in our study. The landraces PER6-DE and PER4-DE showed the highest radical-scavenging activity and reducing power related to their polyphenolic contents. Results also show that yacon can be considered an important source of bioactive compounds with significant differences among the analysed landraces.     

Electrochemical Behavior of Caffeic Acid Assayed with Gold Nanoparticles/Graphene Nanosheets Modified Glassy Carbon Electrode

A gold nanoparticle (AuNP) and graphene nanosheet (GN) modified glassy carbon electrode (GCE) is proposed as voltammetric sensor for caffeic acid assay. The sensor exhibits a surface‐confined and reversible process for oxidation of caffeic acid revealed by cyclic voltammetry. The results show more favorable electron transfer kinetics than the bare GCE. The linear response of the sensor is from 5×10^?7 to 5×10^?5 M with a detection limit of 5×10^?8 M (S/N=3). The AuNP/GN nanocomposite shows more favorable electrochemical activity and should be a kind of more robust and advanced functional material, which provides a promising platform for electrochemical sensors and biosensors. The method was successfully applied to detect caffeic acid in pharmaceutical tablets with satisfactory results.     

Anticholinesterase,antioxidant activity and phytochemical investigation into aqueous extracts from five species of Agrimonia genus

Aqueous extracts of aerial flowering parts of five Agrimonia species (Rosaceae): Agrimonia coreana Nakai, Agrimonia japonica (Miq.) Koidz, Agrimonia procera Wallr., Agrimonia eupatoria L. and Agrimonia leucantha Kunze were investigated on their antioxidant activity, measured using five different methods; the best was the extract from A. procera with IC₅₀ values from 6 to 29 μg/mL. All the extracts displayed inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) at the tested concentration of 100 μg/mL. We found the highest inhibition of cholinesterase in the extract of A. japonica with inhibition 70.4% for AChE and 79.8% for BuChE. These findings are statistically significant in comparison with those of other extracts (p < 0.001). The phytochemical analyses showed that the antioxidant activity of Agrimonia extracts can be affected especially by hexahydroxydiphenoyl (HHDP)-glucose and quercetin glycosides, and inhibition of cholinesterases by apigenin, luteolin and quercetin glycosides.     

Electroanalysis of Caffeic Acid in Red Wine and Investigation of Thermodynamic Parameters Using an Ag Nanoparticles Modified Poly(Thiophene) Film Glassy Carbon Electrode

A silver nanoparticle decorated poly(thiophene) modified glassy carbon electrode (GCE) was prepared for determination of caffeic acid. The Ag/PTh/GCE surface was characterized by scanning electron microscopy (SEM) and energy‐dispersive X‐ray (EDX) spectroscopy. The modified electrode has shown higher electrocatalytic activity towards the oxidation of caffeic acid. The peak current of was found linear in the concentration range from 1.00×10^?8 to 4.83×10^?6 M with a detection limit of 5.3×10^?9 M (S/N=3). The modified electrode was used for determination of CA concentration in red wine samples. The thermodynamic constants, entropy change (ΔS), enthalpy change (ΔH) and Gibbs free energy change (ΔG) were calculated as ?166.34 J/(mol K), ?154.24 kJ/mol and ?104.75 kJ/mol at 25 °C, respectively.     

Could be radiolabeled flavonoid used to evaluate infection?

The aim of this study was to determine whether [¹³¹I]apigenin is a powerful and discrimination infection from inflammation for scintigraphic imaging. The study was carried out in inflamed rats with Staphylococcus aureus (S. aureus) and sterile inflamed rats with turpentine oil. Biodistribution study of [¹³¹I]apigenin was performed in the rats. Apigenin was labeled with ¹³¹I by iodogen method. Obtained [¹³¹I]apigenin with high yield (98%) was injected i.v. to both group rats. The results were expressed as the percent uptake of injected dose per gram of organ (%ID/g), the bacterial infected and sterile inflamed muscles. Binding of [¹³¹I]apigenin to the infected thigh muscle (target muscle = T) and normal thigh muscle (non-target muscle = NT) ratio (T/NT = 4.51 at 15 min) was higher than binding to bacterial inflamed muscle (T/NT = 2.25 at 15 min) of rats. [¹³¹I]apigenin showed good localization in both inflamed tissues. This uptake in the sterile inflamed tissue is higher than bacterial infected tissue. [¹³¹I]apigenin might be useful for imaging of inflamed tissues. However, it is not discriminate sterile inflamed tissue from bacterial infected tissue.