Main View
This view is used for searching all possible sources.
First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
1
Total antioxidant potential of resinous exudates from Heliotropium species, and a comparison of the ABTS and DPPH methods.
1999-06-01

Total reactive antioxidant potential (TRAP) of resinous exudates from Heliotropium species was evaluated by measuring the bleaching of stable free radicals. The antioxidant capacity of the resinous exudates in Trolox equivalents, evaluated from the bleaching of ABTS derived radical cations, ranged from 2.0 M (H. ...

PubMed

2
Synthesis and free radical scavenging activity of coumarin derivatives containing a 2-methylbenzothiazoline motif.
2011-08-25

Coumarin and benzothiazole scaffolds can be found in a number of natural or synthetic antioxidants. In an effort to develop a novel radical scavenger and potential antioxidant, a series of coumarin derivatives containing 2-methylbenzothiazoline motif and related compounds was synthesized and evaluated for their DPPH (1,1-diphenyl-2-picrylhydrazyl) and ...

PubMed

3
Synthesis and antioxidant capacities of hydroxyl derivatives of cinnamoylphenethylamine in protecting DNA and scavenging radicals.
2010-12-03

Cinnamoylphenethylamine (CNPA) derivatives including feruloylphenethylamine (FRPA), caffeoylphenethylamine (CFPA), cinnamoyltyramine (CNTA), feruloyltyramine (FRTA) and caffeoyltyramine (CFTA) were synthesized in order to investigate the influence of the number and position of hydroxyl group on Cu(2+)/glutathione (GSH) and 2,2'-azobis(2-amidinopropane hydrochloride) ...

PubMed

4
Anti-inflammatory, cyclooxygenase (COX)-2, COX-1 inhibitory, and free radical scavenging effects of Rumex nepalensis.
2010-04-08

Evaluation of the topical anti-inflammatory activity of chloroform and ethyl acetate extracts of RUMEX NEPALENSIS roots in a TPA-induced acute inflammation mouse model demonstrated a significant reduction in ear edema. The extracts were further tested on purified enzymes for COX-1 and COX-2 inhibition to elucidate their mechanism of action, and a strong inhibition was observed. Six anthraquinones ...

PubMed

5
Antioxidant bibenzyl derivatives from Notholaena nivea Desv.
2011-03-17

Four new bibenzyl derivatives were isolated, together with other known bibenzyls, by bioassay-guided fractionation of a CHCl?-MeOH extract of Notholaena nivea Desv. (Pteridaceae) aerial parts. The structures were elucidated by NMR, ESIMS and other spectral analyses. Their antioxidative effects towards superoxide, lipidic peroxidation and the ...

PubMed

6
Radical scavenging-linked antioxidant activity of ethanolic extracts of diverse types of extra virgin olive oils.
2008-08-08

The present study evaluated the radical scavenging-linked antioxidant activity of hexane/80% ethanol extracts from several types of extra virgin olive oils (EVOOs) derived from varieties arbequina, hojiblanca, picual, their blends, and pure olive oil (POO). The antioxidant potential of the olive oil extracts was assessed by radical ...

PubMed

7
Studies on the antioxidant activity of Echinacea root extract.
2000-05-01

Methanol extracts of freeze-dried Echinacea (E. angustifolia, E. pallida, and E. purpurea) roots were examined for free radical scavenging capacities and antioxidant activities. Root extracts of E. angustifolia, E. pallida, and E. purpurea were capable of scavenging hydroxyl radical. Similar scavenging activities for each variety were found for both ...

PubMed

8
Isoeugenol-based novel potent antioxidants: Synthesis and reactivity.
2011-07-28

We are attempting to develop the novel phenolic synthetic antioxidants aimed at retarding the effects of free radicals and oxidants. The phenolic compounds (7-12) were synthesized by Friedel-Crafts alkylation of isoeugenol (1) and phenol derivatives (2-6) and their structures were determined by spectroscopic methods. All the synthesized phenolic compounds ...

PubMed

9
Absolute rate constants of alkoxyl radical reactions in aqueous solution. [Tert-butyl hydroperoxide
1987-04-23

The pulse radiolysis technique was used to generate the alkoxyl radical derived from tert-butyl hydroperoxide (/sup t/BuOOH) in aqueous solution. The reactions of this radical with 2,2'-azinobis(3-ethyl-6-benzothiazolinesulfonate) (ABTS) and promethazine were monitored by kinetic spectroscopy. The ...

Energy Citations Database

10
Antioxidants determination with laccase.
2006-12-01

The spectrophotometric method of antioxidants determination using recombinant laccase Polyporus pinsitus (rPpL) and Myceliophthora thermophila (rMtL) was developed. The method includes simultaneous oxidation of the antioxidant and high reactive laccase substrate producing chromophoric radical cation. As laccase substrates ABTS and other high reactive ...

PubMed

11
Ferrocenyl-substituted curcumin: can it influence antioxidant ability to protect DNA?
2011-02-23

The antioxidant capacities of ferrocenyl-substituted curcumin derivatives including 1,7-bis(p-hydroxy-m-methoxyphenyl)-4-ferrocenylidene-hepta-1,6-diene-3,5-dione (FCU), 1-(p-hydroxy-m-methoxyphenyl)-3-hydroxy-7-ferrocenyl-hepta-1,4,6-trien-5-one (FFT), and 1-(p-hydroxy-m-methoxyphenyl)-5-ferrocenyl-penta-1,4-dien-3-one (FDZ) were evaluated in 2,2'-azobis(2-amidinopropane ...

PubMed

12
Formylmethyl and formylmethylperoxyl radicals and their chlorinated derivatives. Formation and reactions in irradiated aqueous solutions
1996-09-26

The formylmethyl radical, {sup .}CH{sub 2}CHO, is known to act as an oxidant. For comparison, the chlorinated analogues, {sup .}CCl{sub 2}CHO and {sup .}CCl{sub 2}CClO, were produced in irradiated aqueous solutions and their oxidation reactions studied. The {sup .}CCl{sub 2}CHO radical is an oxidizing species, which reacts with ascorbate, ...

Energy Citations Database

13
[The determination of total concentration and activity of antioxidants in foodstuffs].

We developed a new method for the analysis of active antioxidants that is based on their reactions with the ABTS+. cation radical obtained by oxidation of ABTS, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt. The feasibility of this method was confirmed by electrochemical and kinetic studies of model ...

PubMed

14
Isolation and identification of antioxidant compounds from Ligularia fischeri.
2010-08-01

The plant Ligularia fischeri var. spiciformis Nakai, a well-known edible medicinal herb in Korea, has been used to treat maladies such as jaundice, scarlet fever, rheumatoid arthritis, and hepatic function failure. In this research, 4 major antioxidant compounds were detected from this plant's leaves using an on-line high-performance liquid chromatography (HPLC)-ABTS screening ...

PubMed

15
Use of countercurrent chromatography during isolation of 6-hydroxyluteolin-7-O-?-glucoside, a major antioxidant of Athrixia phylicoides.
2010-12-29

Athrixia phylicoides, an indigenous South African herbal tea, has potential as a source of nutraceutical antioxidant extracts. Countercurrent chromatography (CCC) was employed as part of a multi-step process to isolate one of the major antioxidant compounds in A. phylicoides extracts. Antioxidant activity of the extracts was comparable to commercial nutraceutical extracts from Aspalathus linearis ...

PubMed

16
New antioxidant bibenzyl derivative and isoflavonoid from the Tunisian Salsola tetrandra Folsk.
2011-08-11

Two new phytochemical compounds, Tetranins A and B, 1-(3,5'-dihydroxy-4'-m�thoxyphenyl)-2-phenylethanol 1 and 5,2'-dihydroxy-5'-methoxy-6,7-methylenedioxy-isoflavone 2, were isolated from the EtOAc extract of Salsola tetrandra roots. They exhibited a significant antioxidant effect in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and 2,2'-azinobis ...

PubMed

17
Lipoxygenase inhibitory constituents from rhubarb.
2008-05-15

Phytochemical study on the ethanol extract of rhubarb led to the isolation of fifteen compounds, including five anthraquinones: chrysophanol (1), physcion (2), emodin (7), chrysophanol-8-O-beta-D: -glucopyranoside (9) and emodin-8-O-beta-D: -glucopyranoside (15), and ten stilbenes: desoxyrhaponticin (3), rhaponticin (4), resveratrol (5), desoxyrhapotigenin (6), rhapontigenin (8), ...

PubMed

18
Induction, Isolation, and Characterization of Two Laccases from the White Rot Basidiomycete Coriolopsis rigida
2002-04-01

Previous work has shown that the white rot fungus Coriolopsis rigida degraded wheat straw lignin and both the aliphatic and aromatic fractions of crude oil from contaminated soils. To better understand these processes, we studied the enzymatic composition of the ligninolytic system of this fungus. Since laccase was the sole ligninolytic enzyme found, we paid attention to the oxidative capabilities ...

PubMed Central

19
Selective ABTS radical-scavenging activity of prenylated flavonoids from Cudrania tricuspidata.
2006-02-01

The antioxidative properties of five prenylated flavonoids, including new flavanone (2), from the root bark of Cudrania tricuspidata were examined against the ABTS, DPPH, and hydroxyl radicals. In most of the assays to determine their antioxidative properties, the ABTS activity was strongly correlated with DPPH because both methods are ...

PubMed

20
Antioxidant activity of a catechol derived from abietic acid.
2006-01-25

The demand for novel effective antioxidant-based drugs has led to the synthesis and evaluation of the antioxidant potential in several molecules derived from natural compounds. In this work the in vitro antioxidant activity of an abietic acid-derived catechol (methyl 11,12-dihydroxyabietate-8,11,13-trien-18-oate, MDTO) was evaluated. This substance, ...

PubMed

First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
21
Antioxidant xanthone derivatives induce cell cycle arrest and apoptosis and enhance cell death induced by cisplatin in NTUB1 cells associated with ROS.
2011-02-04

In an effort to develop novel antioxidant as anticancer agents, a series of xanthones were prepared. In vitro screening, the synthetic xanthones revealed significant inhibitory effects on xanthine oxidase and ABTS radical-cation scavenging activity. The selective compounds 2 and 8 induced an accumulation of NTUB1 cells in the G(1) phase arrest and cellular ...

PubMed

22
Antioxidant hispidin derivatives from medicinal mushroom Inonotus hispidus.
2011-01-01

Two natural antioxidants, named inonotusin A (1) and B (2), were isolated from the methanolic extract of the fruit bodies of Inonotus hispidus, together with (E)-4-(3,4-dihydroxyphenyl)but-3-en-2-one (3), hispidin (4) and 3,4-dihydroxybenzaldehyde (5). Their structures were identified by means of extensive NMR and MS data analysis. Compounds 1, 2 and 4 exhibited significant scavenging activity ...

PubMed

23
Chemical kinetic behavior of chlorogenic acid in protecting erythrocyte and DNA against radical-induced oxidation.
2008-11-26

As an abundant ingredient in coffee, chlorogenic acid (CGA) is a well-known antioxidant. Although some works have dealt with its radical-scavenging property, the present work investigated the protective effects of CGA on the oxidation of DNA and on the hemolysis of human erythrocytes induced by 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH) by means of chemical kinetics. ...

PubMed

24
Synthesis and Evaluation of Analgesic and Anti-inflammatory Activities of Most Active Free Radical Scavenging Derivatives of Embelin-A Structure-Activity Relationship.
2011-01-01

Antioxidant and related properties of the plant Embelia ribes and embelin are well known. In the present study embelin was condensed with various aromatic substituted primary amines to yield ten new and one reported derivatives along with monomethyl embelin. All these compounds along with embelin were evaluated for in vitro antioxidant activity using ...

PubMed

25
S-carbamoylation impairs the oxidant scavenging activity of cysteine: its possible impact on increased LDL modification in uraemia.
2011-01-26

Carbamoylation is the non-enzymatic reaction of cyanate with amino-, hydroxy- or thiol groups. In vivo, amino group modification (N-carbamoylation) resulting in altered function of proteins/amino acids has been observed in patients suffering from uraemia due to urea-derived cyanate. Uraemia has been linked to impaired antioxidant defense. As thiol-compounds like cysteine, ...

PubMed

26
Pulse radiolysis and cyclic voltammetry studies of redox properties of phenothiazine radicals
2006-09-01

One-electron transfer equilibria between seven phenothiazines were characterized by pulse radiolysis, producing radical-cations via oxidation by Br2�? or (SCN)2�? radicals. The reduction potentials of the phenothiazine radicals were determined by cyclic voltammetry. As an independent check, the redox equilibrium between one ...

NASA Astrophysics Data System (ADS)

27
ABT-737 Synergizes with Chemotherapy to Kill Head and Neck Squamous Cell Carcinoma Cells via a Noxa-Mediated PathwayS?
2009-05-25

Overexpression of Bcl-XL, an antiapoptotic Bcl-2 family member, occurs in a majority of head and neck squamous cell carcinomas (HNSCCs) and correlates with chemotherapy resistance in this disease. Overexpression of Bcl-2 is also observed in HNSCC, albeit less frequently. We have previously shown that peptides derived from the BH3 domains of ...

PubMed Central

28
Antioxidant phenolic compounds of Dracaena cambodiana.
2010-12-06

The antioxidant activities of the petroleum ether, ethyl acetate, n-BuOH and water extract fractions from Dracaena cambodiana Pierre ex Gagnep were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest DPPH?, ABTS+ and Superoxide anion radical-scavenging capacities. ...

PubMed

29
Screening of antimutagenicity via antioxidant activity in different extracts from the flowers of Phlomis crinita Cav. ssp mauritanica munby from the center of Tunisia.
2009-01-01

For centuries, plants have been used in traditional medicines, and there has been recent interest in the chemopreventive properties of compounds derived from plants. In the present study, we investigated the free-radical-scavenging, antioxidant, and antimutagenic potential of polar extracts from Phlomis crinita Cav. flowers. Ethyl acetate, chloroform, and ...

PubMed

30
Antioxidant and prooxidant nature of hydroxycinnamic acid derivatives ferulic and caffeic acids.
2010-09-17

Dietary polyphenols are beneficial to human health by exerting various biological effects. Ferulic and caffeic acids are hydroxycinnamic acid derivatives widely distributed in plant-derived food products. Studies indicate that some dietary compounds may have concentration-dependent antioxidant or prooxidant activities. The present study concerns such ...

PubMed

31
'Seed' analysis of off-target siRNAs reveals an essential role of Mcl-1 in resistance to the small-molecule Bcl-2/Bcl-XL inhibitor ABT-737.
2006-12-18

ABT-737 is a subnanomolar inhibitor of the antiapoptotic proteins Bcl-2, Bcl-X(L) and Bcl-w. Although ABT-737 triggers extensive cell death in many small-cell lung carcinoma (SCLC) cell lines, some of the SCLC cell lines and the majority of the cancer cell lines derived from other solid tumors were found to be resistant to ...

PubMed

32
Derivative at a Point

illustrating how to use the definition of derivative to calculate the derivative of a radical at a specific point.

NSDL National Science Digital Library

33
Study of genotoxic, antigenotoxic and antioxidant activities of the digallic acid isolated from Pistacia lentiscus fruits.
2009-06-27

The digallic acid obtained from the fruit Pistacia lentiscus exhibits an inhibitory activity against nitrofurantoine and B[a]P induced genotoxicity when tested by the SOS chromotest bacterial assay system in the presence of Escherichia coli PQ37 strain. The antioxidant activity of the tested compound was determined by its ability to scavenge the free radical ...

PubMed

34
Haloalkoxy Derivatives of the Cyclophosphonitrilic Chloride ...
1977-01-11

... Alkoxy radicals, Halogen compounds, Chemical derivatives ... radicals, Phosphorus compounds, Amides ... Subject Categories : ORGANIC CHEMISTRY. ...

DTIC Science & Technology

35
Autographic assay for the rapid detection of antioxidant capacity of liquid and semi-solid pharmaceutical formulations using ABTS�+ immobilized by gel entrapment.
2010-07-24

An autographic assay suitable for the detection of antioxidant compounds in a complex matrix (liquid and semi-solid pharmaceutical formulations) or in isolated compounds was described. The pre-formed radical monocation of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(�+)) was generated by oxidation of ABTS with ...

PubMed

36
Autographic Assay for the Rapid Detection of Antioxidant Capacity of Liquid and Semi-solid Pharmaceutical Formulations Using ABTS�+ Immobilized by Gel Entrapment
2010-07-24

An autographic assay suitable for the detection of antioxidant compounds in a complex matrix (liquid and semi-solid pharmaceutical formulations) or in isolated compounds was described. The pre-formed radical monocation of 2,2?-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS�+) was generated by oxidation of ...

PubMed Central

37
A novel method for flow injection analysis of total antioxidant capacity using enzymatically produced ABTS*+ and biamperometric detector containing interdigitated electrode.
2006-05-02

Application of interdigitated array microelectrodes as electrochemical sensors for determination of antioxidant capacity is reported. Electrochemical measurements with interdigitated electrodes (IDE) were studied in both stationary solutions and the flow system. The method is based on biamperometric measurements using ABTS(*+)|ABTS redox couple in phosphate buffer solution, pH ...

PubMed

38
Feruloylacetone as the model compound of half-curcumin: synthesis and antioxidant properties.
2011-02-01

In order to clarify the contribution of phenolic and enolic hydroxyl group to the antioxidant capacity of feruloylacetone, a model compound of half-curcumin, 6-(p-hydroxy-m-methoxyphenyl)-5-hexene-2,4-dione (FT), 6-(p-benzyloxy-m-methoxyphenyl)-5-hexene-2,4-dione (BMFT), 6-(m,p-dihydroxyphenyl)-5-hexene-2,4-dione (DDFT), 6-(p-hydroxy-m-methoxyphenyl)hexane-2,4-dione (DHFT), ...

PubMed

39
Daidzein as an antioxidant of lipid: effects of the microenvironment in relation to chemical structure.
2008-10-09

Isoflavone daidzein (D, pK a1 = 7.47 +/- 0.02 and pK a2 = 9.65 +/- 0.07) was, through a study of the parent compound and its three methyl anisol derivatives 7-methyldaidzein (7-Me-D, pK a = 9.89 +/- 0.05), 4'-methyldaidzein (4'-Me-D, pK a = 7.43 +/- 0.03), and 7,4'-dimethyldaidzein (7,4'-diMe-D), found to retard lipid oxidation in liposomal membranes through two mechanisms: ...

PubMed

40
Synthesis and antioxidant properties of diphenylmethane derivative bromophenols including a natural product.
2010-10-01

Bromination of bis(3,4-dimethoxyphenyl)methanone (5) gave four products (6-9) with mono, di, tri, and tetra Br under different conditions. Reduction and demethylation reactions of product 9 with tetra Br were performed, consecutively and a natural product, 5,5'-methylene bis(3,4-dibrombenzene-1,2-diol) (1), was obtained with a 53% yield. Five derivatives, (13-17) ...

PubMed

First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
41
Syntheses of aromatic substituted hydrazino-thiazole derivatives to clarify structural characterization and antioxidant activity between 3-arylsydnonyl and aryl substituted hydrazino-thiazoles.
2007-08-01

This work clarifies the structural characterization and antioxidant activity between aromatic and 3-arylsydnonyl substituted hydrazino-thiazoles by further synthesizing a series of aromatic ring-substituted hydrazino-thiazole derivatives 8a-h and 9a-h. Hydrazino-thiazole derivatives 8a-h and 9a-h were obtained by reacting aromatic or heterocyclic aromatic ...

PubMed

42
17.9.1 Radical cations of aliphatic amines and derivatives
2009-01-01

This document is part of Subvolume E2 �Phosphorus-Centered Radicals, Radicals Centered on Other Heteroatoms, Organic Radical Ions� of Volume 26 �Magnetic Properties of Free Radicals� of Landolt-B�rnstein Group II �Molecules and Radicals�.

NASA Astrophysics Data System (ADS)

43
Free radical-scavenging delta-lactones from Boletus calopus.
2006-11-07

The methanol extracts from the fruiting body of the mushroom Boletus calopus showed free radical-scavenging activity. Bioactivity-guided fractionation of the methanol extracts led to a new hydroxylated calopin named calopin B, along with the known delta-lactones calopin and cyclocalopin A. The structure of the new calopin analogue was elucidated by spectroscopic methods. All ...

PubMed

44
Assessment of antioxidant activity of cane brown sugars by ABTS and DPPH radical scavenging assays: determination of their polyphenolic and volatile constituents.
2005-12-28

Seven cane brown sugars (four from La R�union, two from Mauritius, and one from France) were investigated for their polyphenol content and volatile composition in relation to their free radical scavenging capacity determined by ABTS and DPPH assays. The thin layer coated on the sugar crystal was extracted by Soxhlet extractor with dichloromethane. The ...

PubMed

45
Laccase activity tests and laccase inhibitors.
2000-03-10

Sulfhydryl organic compounds described as laccase inhibitors: dithiothreitol, thioglycolic acid, cysteine, diethyldithiocarbamic acid, and sodium azide were tested for their activity toward laccase of Trametes versicolor in different test systems utilising 2, 2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2, 6-dimethoxyphenol as enzyme substrates. Only ...

PubMed

46
ABT-869, a promising multi-targeted tyrosine kinase inhibitor: from bench to bedside
2009-07-30

Tyrosine Kinase Inhibitors (TKI) have significantly changed the landscape of current cancer therapy. Understanding of mechanisms of aberrant TK signaling and strategies to inhibit TKs in cancer, further promote the development of novel agents.ABT-869, a novel ATP-competitive receptor tyrosine kinase inhibitor is a potent inhibitor of members of the vascular endothelial growth ...

PubMed Central

47
Fenton-Like Reaction Catalyzed by the Rare Earth Inner Transition Metal Cerium
2008-07-01

Cerium (Ce) is a rare earth metal that is not known to have any biological role. Cerium oxide materials of several sizes and shapes have been developed in recent years as a scaffold for catalysts. Indeed even cerium oxide nanoparticles themselves have displayed catalytic activities and antioxidant properties in tissue culture and animal models. Because of ceria's ability to cycle between the +3 ...

PubMed Central

48
Helichrysum monizii Lowe: Phenolic Composition and Antioxidant Potential.
2011-08-12

INTRODUCTION: In Madeira Archipelago there are four endemic Helichyrsum species and three of them are used in the traditional medicine. Helichrysum monizii is a rare endemism with very scarce information available concerning its uses in the local traditional medicine. OBJECTIVE: The aim of this work was to study for the first time Helichrysum monizii in terms of its antioxidant capacity and the ...

PubMed

49
From vineyard to glass: agrochemicals enhance the melatonin and total polyphenol contents and antiradical activity of red wines.
2011-05-17

? Resistance inducers are a class of agrochemicals, including benzothiadiazole and chitosan, which activate the plant own defence mechanisms. In this work, open-field treatments with plant activators were performed on two red grape (Vitis vinifera L.) varieties cultivated in different localities, Groppello (Brescia, Lombardia, Italy) and Merlot (Treviso, Veneto, Italy). Treatments were carried out ...

PubMed

50
Organic Derivatives of Heteropoly Molybdates.
1976-11-01

... ELECTRON TRANSFER, ORGANIC RADICALS, ANIONS, STOICHIOMETRY, ARSENIC COMPOUNDS, CHEMICAL DERIVATIVES, TUNGSTATES ...

DTIC Science & Technology

51
CARBOHYDRATE DERIVATIVES FOR PROTECTION FROM ...
1962-10-25

... Abstract : Carbohydrate derivatives of established radioprotective ... ACETYL RADICALS, AMIDES, CARBOHYDRATES, GUANIDINES, SULFUR ...

DTIC Science & Technology

52
Boron Derivatives of 3-Methylpyrazole.
1984-12-01

... Descriptors : *METHYL RADICALS, *BORATES, *CHEMICAL DERIVATIVES, *PYRAZOLES, NUCLEAR MAGNETIC RESONANCE, SYNTHESIS ...

DTIC Science & Technology

53
Optimization and validation of post-column assay for screening of radical scavengers in herbal raw materials and herbal preparations.
2010-10-12

On-line method, which combines HPLC distribution and post-column reaction, was designed for the search of individual antioxidants. Optimization of the assay was performed evaluating optimal ABTS(+) radical cation concentration in the reactor, reaction time, impact of flow rate, reaction coil length. HPLC-ABTS assay validation in this ...

PubMed

54
Comparison of antioxidant abilities of magnolol and honokiol to scavenge radicals and to protect DNA.
2011-06-23

The antioxidant properties of magnolol and honokiol were evaluated in the experimental systems of reducing ONOO(-) and (1)O(2), bleaching ?-carotene in linoleic acid (LH) emulsion, and trapping 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS(+)) and 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), and then were ...

PubMed

55
Poly(ADP-ribose) polymerase and XPF�ERCC1 participate in distinct pathways for the repair of topoisomerase I-induced DNA damage in mammalian cells
2011-05-10

Poly(ADP-Ribose) (PAR) polymerase (PARP) inhibitors represent a promising class of novel anticancer agents. The present study explores the molecular rationale for combining veliparib (ABT-888) with camptothecin (CPT) and its clinical derivatives, topotecan and irinotecan. ABT-888 inhibited PAR induction by CPT and increased CPT-induced ...

PubMed Central

56
Poly(ADP-ribose) polymerase and XPF-ERCC1 participate in distinct pathways for the repair of topoisomerase I-induced DNA damage in mammalian cells.
2011-01-11

Poly(ADP-Ribose) (PAR) polymerase (PARP) inhibitors represent a promising class of novel anticancer agents. The present study explores the molecular rationale for combining veliparib (ABT-888) with camptothecin (CPT) and its clinical derivatives, topotecan and irinotecan. ABT-888 inhibited PAR induction by CPT and increased CPT-induced ...

PubMed

57
Derivatization of single-walled carbon nanotubes with redox mediator for biocatalytic oxygen electrodes.
2010-06-12

Single-walled carbon nanotubes (SWCNTs) were covalently modified with a redox mediator derived from 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), and implemented in the construction of electrodes for biocatalytic oxygen reduction. The procedure is based on: covalent bonding of mediator to nanotubes, placing the nanotubes directly on the ...

PubMed

58
Effective sensitization of temozolomide by ABT-888 is lost with development of TMZ resistance in glioblastoma xenograft lines
2009-01-27

Resistance to temozolomide (TMZ) and radiotherapy (RT) is a major problem for patients with GBM but may be overcome using the PARP-inhibitor ABT-888. Using two primary GBM xenografts, the efficacy of ABT-888 combined with RT and/or TMZ was evaluated. Treatment with ABT-888 combined with TMZ resulted in significant survival prolongation ...

PubMed Central

59
Acquired resistance to ABT-737 in lymphoma cells that up-regulate MCL-1 and BFL-1
2010-04-22

ABT-737 is a small-molecule antagonist of BCL-2 currently under evaluation in clinical trials in the oral form of ABT-263. We anticipate that acquired resistance to this promising drug will inevitably arise. To study potential mechanisms of resistance to ABT-737, we derived resistant lines from initially sensitive ...

PubMed Central

60
Radical scavenging activity and composition of raspberry (Rubus idaeus) leaves from different locations in Lithuania.
2006-11-14

Raspberry (Rubus idaeus) leaves, collected in different locations of Lithuania were extracted with ethanol and the extracts were tested for their antioxidant activity (AA) by using ABTS(.)(+) decolourisation and DPPH(.) scavenging methods. All extracts were active, with radical scavenging capacity at the used concentrations from 20.5 to 82.5% in DPPH(.) ...

PubMed

First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
61
Fire Retardant Polyester Resins.
1976-11-16

... Polyester plastics, Addition reactions, Phosphorus compounds, Oxychlorides, Methyl radicals, Amides, Alkoxy radicals, Chemical derivatives. ...

DTIC Science & Technology

62
An EPR Study of the Thermal Decomposition of TNT/HMB ...
1985-08-22

... Radical signals are observed which result from at ... spectra of radicals derived from ... Descriptors : *METHYL RADICALS, *TNT, *PYROLYSIS, *HEXYL ...

DTIC Science & Technology

63
Therapeutic Efficacy of ABT-737, a Selective Inhibitor of BCL-2, in Small Cell Lung Cancer
2008-04-01

Bcl-2 is a central regulator of cell survival that is overexpressed in the majority of small cell lung cancers (SCLC) and contributes to both malignant transformation and therapeutic resistance. We compared primary SCLC xenografts prepared from de novo human tumors with standard cell line�based xenografts in the evaluation of a novel and highly potent small molecule inhibitor of Bcl-2, ...

PubMed Central

64
Reassessment of antioxidant activity of arbutin: multifaceted evaluation using five antioxidant assay systems.
2010-04-01

Arbutin, a practically used skin-lightening agent, has been reported to possess a weak antioxidant activity compared to that of its precursor, hydroquinone. However, its antioxidant activity has not been systematically evaluated. Hence, this study reassessed its activity using five assay systems. Assays were first performed using model radicals, DPPH ...

PubMed

65
Lutein content and in vitro antioxidant activity of different cultivars of Indian marigold flower ( Tagetes patula L.) extracts.
2010-07-28

Three different cultivars of marigold flowers ( Tagetes patula L.) (marigold orange, marigold yellow, and marigold red) were analyzed for the lutein ester contents, and the in vitro antioxidative activities of the flower extracts were compared. The total antioxidant capacity, reducing power, hydroxyl, DPPH, and ABTS(*+) radical scavenging activities, iron ...

PubMed

66
Antioxidant and antigenotoxic activities in Acacia salicina extracts and its protective role against DNA strand scission induced by hydroxyl radical.
2011-05-04

The antioxidant potency of Acacia salicina extracts was investigated. Total antioxidant capacity was determined using an ABTS(+) assay. Superoxide radical scavenging was measured using riboflavin-light-nitro blue tetrazolium (NBT) assay. In addition, the content of phenols, total flavonoids and sterols were measured in the tested extracts. The petroleum ...

PubMed

67
Phenolic content and in vitro inhibitory effects on oxidation and protein glycation of some Thai medicinal plants.
2010-10-01

Fifteen medicinal plant extracts were investigated for: total phenolic content and free radical scavenging effect by DPPH and ABTS assays; anti-lipid peroxidation activity by TBARS; and for antiglycation activity. The results revealed that the total phenolic content showed good correlation with free radical scavenging by ...

PubMed

68
Carbonium Ion Radicals and Oxy Radicals.
1966-01-01

The study concerns the comparison of ferrocenylmethyl derivatives (chlorides mostly) with benzyl derivatives with respect to unimolecular and bimolecular nucleophilic substitution. A quantitative comparison is found which allows the conclusion that the ex...

National Technical Information Service (NTIS)

69
Antioxidant potential of bitter cumin (Centratherum anthelminticum (L.) Kuntze) seeds in in vitro models
2011-05-20

BackgroundBitter cumin (Centratherum anthelminticum (L.) Kuntze), is a medicinally important plant. Earlier, we have reported phenolic compounds, antioxidant, and anti-hyperglycemic, antimicrobial activity of bitter cumin. In this study we have further characterized the antioxidative activity of bitter cumin extracts in various in vitro models.MethodsBitter cumin seeds were extracted with a ...

PubMed Central

70
Antioxidant activity of nine Fabaceae species growing in Serbia and Montenegro.
2007-12-03

The aim of this study was to investigate antioxidant capacity of nine Fabaceae species collected on the mountains of Serbia and Montenegro. Antioxidant assays with various reaction mechanisms were used, including total phenolic content by Folin-Ciocalteu, DPPH radical scavenging capacity, Trolox equivalent antioxidant capacity (TEAC) values by ABTS ...

PubMed

71
Antioxidant activity of Maytenus ilicifolia root bark.
2006-03-06

Maytenus ilicifolia is an important plant with potential on cancer treatment and has been largely used in Brazil and other countries. We have evaluated the crude ethanolic extract of M. ilicifolia as a potential antioxidant source using an assay based on the bleaching of the radical monocation 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) ...

PubMed

72
Polysaccharides as potential antioxidative compounds for extended-release matrix tablets.
2009-10-22

The objective of this study was to identify polysaccharides with antioxidant properties for use as potential antioxidative compounds for extended-release matrix tablets. The antioxidant properties of five different polysaccharides, high molecular weight alginate (H-ALG), low molecular weight alginate (L-ALG), high molecular weight chitosan (H-chitosan), low molecular weight chitosan (L-chitosan), ...

PubMed

73
Antioxidant properties of sour cherries (Prunus cerasus L.): role of colorless phytochemicals from the methanolic extract of ripe fruits.
2008-02-27

Many edible plant metabolites are known to be useful as cellular antioxidants. In the search for antioxidative chemicals from native fruits of the Campania region of Italy, Prunus cerasus L., an acidic cherry widely used for culinary purposes, has been studied. Fruit crude extracts (MeOH, EtOAc, and hexane) were submitted to an antioxidative screening using specific assay media characterized from ...

PubMed

74
Antioxidant activity in human faeces.
2000-11-01

Scarcely-absorbed antioxidants might reach the large bowel and exhibit antioxidant activity, opposing the action of reactive O species by bacterial and cellular metabolism and thus contributing to protection from oxidative damage-induced gastrointestinal diseases. This study was carried out to evaluate the antioxidant activity in the faeces of a group of healthy subjects on a freely-selected diet, ...

PubMed

75
DNA protective properties of vanillin against gamma-radiation under different conditions: possible mechanisms.
2007-06-17

Ionizing radiation is an important genotoxic agent. Protecting against this form of toxicant, especially by a dietary component, has several potential applications. In the present study, we have examined the ability of vanillin (4-hydroxy-3-methoxybenzaldehyde), a naturally occurring food flavouring agent, to inhibit radiation-induced DNA damage measured as strand breaks under in vitro, ex vivo ...

PubMed

76
The Synthesis of Aldos-4-ulose Derivatives and Branched ...
1975-11-01

... BENZYL RADICALS, POTASSIUM COMPOUNDS, ACETALS, ARABINOSE, CHEMICAL DERIVATIVES, HEXOSES, PIPERIDINES, XYLOSE ...

DTIC Science & Technology

77
The Synthesis and Study of New Ribavirin Derivatives and ...
1981-09-01

... Azoles, *Carboranyl radicals, *Amides, Chemical derivatives, Synthesis( Chemistry), Molecular structure, Pyrazoles, Ribonucleic acids, Viruses ...

DTIC Science & Technology

78
T-Butyldimethylsilyl Derivatives of Some Alkylphosphonic and ...
1985-01-01

... Descriptors : *GAS CHROMATOGRAPHY, *ALKYL RADICALS, *PHOSPHONIC ACIDS, *MASS SPECTROMETRY, *CHEMICAL DERIVATIVES ...

DTIC Science & Technology

79
Synthesis of a Thiophene-Containing Bisbenzil and a Derived ...
1979-02-01

... TEMPERATURE, CROSSLINKING(CHEMISTRY), MOLECULAR STRUCTURE, BENZYL RADICALS, THIOPHENES, CHEMICAL DERIVATIVES ...

DTIC Science & Technology

80
Silylated Tetrahydrofuran Derivatives.
1982-12-03

... Descriptors : *REACTION KINETICS, *HYDROGEN, *SILANES, *FURANS, METHYL RADICALS, SILICON, SOLVENTS, CHLORINATION, ANIONS ...

DTIC Science & Technology

First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
First Page Previous Page 1 2 3 4 5 Next Page Last Page
 
81
COMPOUNDS OF HIGH NITROGEN CONTENT IN ...
1944-04-03

... temperature. The stability of these carbonic acid derivates, however, was not affected by the presence of hydrazine radicals. ...

DTIC Science & Technology

First Page Previous Page 1 2 3 4 5 Next Page Last Page