Activities of free radical scavengers in tests designed to detect lipid peroxyl or superoxide radical scavenging

1995 ◽  
Vol 31 ◽  
pp. 140
Author(s):  
C. Carter ◽  
O. Curet ◽  
A. Deffois
Keyword(s):  
Free Radical ◽  
Superoxide Radical ◽  
Radical Scavenging ◽  
Free Radical Scavengers ◽  
Radical Scavengers

scholarly journals Biological Activity of the Methanol and Water Extracts of the Fruits of Anthocyanin-Rich Plants Grown in South-West Poland

2015 ◽  
Vol 10 (3) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Paulina Strugala ◽  
Anna Dudra ◽  
Alicja Z. Kucharska ◽  
Anna Sokół-Łętowska ◽  
Dorota Wojnicz ◽  
...  
Keyword(s):  
Free Radical ◽  
Biological Effects ◽  
Radical Scavenging ◽  
Antibacterial Properties ◽  
Bacterial Biofilm ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Water Extracts ◽  
South West ◽  
Anti Inflammatory

In this study we focused on the chemical composition, antioxidant, anti-inflammatory and antibacterial properties of methanol and water extracts of fruits of six species grown in south-west Poland: blackberry, blackcurrant, chokeberry, cherry, gooseberry and raspberry. No general correlation could be drawn between extract chemical properties (i.e. antioxidant and free radical scavenging) and observed biological effects. However, blackcurrant and blackberry extracts (both methanol and water) appeared to be good antioxidants and free radical scavengers, as well as effective inhibitors of E. coli adhesion to the uroepithelial cells. On the other hand, the poorest antioxidants and free radical scavengers, cherry and gooseberry extracts, also poorly affected bacterial growth, swimming ability and adhesion to epithelial cells. Surprisingly, gooseberry extracts, which showed generally weak effects, appeared to be the most effective inhibitor of bacterial biofilm formation. Additionally, most of the studied extracts showed reasonably strong anti-inflammatory properties.

Target Size Analysis by Radiation Inactivation: The Use of Free Radical Scavengers

2005 ◽  
Vol 230 (7) ◽  
pp. 455-463 ◽  
Author(s):  
Gene C. Ness ◽  
Laura C. Pendleton ◽  
Michael J. McCreery
Keyword(s):  
Enzyme Activity ◽  
Free Radical ◽  
Functional Unit ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Target Size ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Radiation Inactivation ◽  
Glucose 6 Phosphate Dehydrogenase

Several model systems were employed to assess indirect effects that occur in the process of using radiation inactivation analysis to determine protein target sizes. In the absence of free radical scavengers, such as mannitol and benzoic acid, protein functional unit sizes can be drastically overestimated. In the case of glutamate dehydrogenase, inclusion of free radical scavengers reduced the apparent target size from that of a hexamer to that of a trimer based on enzyme activity determinations. For glucose-6-phosphate dehydrogenase, the apparent target size was reduced from a dimer to a monomer. The target sizes for both glutamate dehydrogenase and glucose-6-phosphate dehydrogenase in the presence of free radical scavengers corresponded to subunit sizes when determinations of protein by sodium dodecyl sulfate–polyacrylamide gel electrophoresis or immunoblotting were done rather than enzyme activity. The free radical scavengers appear to compete with proteins for damage by secondary radiation products, since irradiation of these compounds can result in production of inhibitory species. Addition of benzoic acid/mannitol to samples undergoing irradiation was more effective in eliminating secondary damage than were 11 other potential free radical scavenging systems. Addition of a free radical scavenging system enables more accurate functional unit size determinations to be made using radiation inactivation analysis.

Discovery of New N-hydrazinecarbothioamide Indazole Hybrids: As Potential Radical (ABTS and DPPH) Scavengers

2020 ◽  
Vol 17 (9) ◽  
pp. 1177-1185
Author(s):  
Rafaila Rafique ◽  
Arshia ◽  
Kanwal ◽  
Khalid Mohammed Khan ◽  
Sridevi Chigurupati ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Free Radicals ◽  
Free Radical ◽  
Radical Scavenging ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Synthetic Compounds ◽  
Free Radical Generation ◽  
Radical Generation

Background: Free radicals are the main cause of numerous diseases. Their overproduction needs to be controlled in order to combat several ailments. The current study deals with the discovery of new free radical scavengers. Methods: Substituted N-hydrazinecarbothioamide indazoles 1-18 were evaluated for DPPH and ABTS radical scavenging activities. Results: All synthetic compounds possess good radical DPPH and ABTS scavenging potential in the ranges of IC50 = 2.11 ± 0.17 - 5.3 ± 0.11 μM and IC50 = 2.31 ± 0.06 - 5.5 ± 0.07 μM, respectively, as compared to standard ascorbic acid having IC50 = 2.02 ± 0.11 μM for DPPH and IC50 = 2.1 ± 0.07 μM for ABTS. Conclusion: These compounds could serve as leads for antioxidant activity that have the ability to control free radical generation and ward off free radical-induced disorders.

scholarly journals Studies on free radical scavenging substances from microorganisms. II. Neocarazostatins A, B and C, novel free radical scavengers.

1991 ◽  
Vol 44 (8) ◽  
pp. 903-907 ◽  
Author(s):  
SHINICHIRO KATO ◽  
KAZUTOSHI SHINDO ◽  
YOKO KATAOKA ◽  
YUJI YAMAGISHI ◽  
JUNICHIRO MOCHIZUKI
Keyword(s):  
Free Radical ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Free Radical Scavengers ◽  
Radical Scavengers

FREE RADICAL SCAVENGING ACTIVITY OF ACACIA NILOTICA PODS

INDIAN DRUGS ◽  
2014 ◽  
Vol 51 (07) ◽  
pp. 14-22
Author(s):  
T. A Khan ◽  
◽  
A. Gohel
Keyword(s):  
Lipid Peroxidation ◽  
Free Radical ◽  
Radical Scavenging Activity ◽  
Folk Medicine ◽  
Radical Scavenging ◽  
Acacia Nilotica ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Radical Production ◽  
Medicinal Value

Biomolecules can be oxidized by free radicals. This oxidative damage has an important etiological role in aging and the development of diseases like cancer, atherosclerosis, and other inflammatory disorders. Synthetic antioxidants, such as butylated hydroxyl anisole, are good free radical scavengers; however, they can be carcinogenic. Therefore, there is an increasing interest in searching for antioxidants of natural origin. Acacia nilotica has a versatile medicinal value as folk medicine. The present study aims at screening the methanol and aqueous extracts of the pods of Acacia nilotica for antioxidant activity. The effect of these extracts on inhibition of 1, 1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide radicals and of lipid peroxidation was studied. The results indicated that both the extracts exhibited a significant reduction in the DPPH and NO radical production along with a significant reduction in lipid peroxidation. The results indicate the pods of Acacia nilotica to be a cheap and easily available source of antioxidants

Eco-Friendly Approach for the Synthesis of Thiophene Linked Benzothiazepines as Biocompatible Free Radical Scavengers

2021 ◽  
Vol 6 (1) ◽  
pp. 1-6
Author(s):  
P. Sudeep ◽  
K.R. Raghavendra ◽  
R. Sowmya ◽  
K. Ajay Kumar
Keyword(s):  
Free Radical ◽  
Hydroxyl Radical ◽  
Phase Transfer ◽  
Tetrabutylammonium Bromide ◽  
Radical Scavenging ◽  
Phase Transfer Catalyst ◽  
Free Radical Scavengers ◽  
Radical Scavengers ◽  
Citrus Juice

A series of new thiophene tethered benzothiazepines (5a-h) were synthesized through citrus juice mediated (4+3) annulations of thienyl chalcones with 2-aminobenzenethiol in the presence of tetrabutylammonium bromide as phase transfer catalyst under reflux conditions. The synthesized compounds were characterized by spectroscopic and CHN analysis. To check the antioxidant potentials of the synthesized compounds, in vitro DPPH and hydroxyl radical scavenging assays were conducted. The results shows that amongst the series, compounds 5b with (21.44-49.72%) and (16.88-42.60%); 5c with (24.88-56.00%) and (22.33-53.12%); and 5h with (22.80-47.10%) and (15.33-44.12%) excellent DPPH and hydroxyl radical potencies comparable with the respective standards used in the experiments.

scholarly journals The Nrf2/HO-1 Axis as Targets for Flavanones: Neuroprotection by Pinocembrin, Naringenin, and Eriodictyol

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Solomon Habtemariam
Keyword(s):  
Free Radical ◽  
Neuroprotective Effect ◽  
Radical Scavenging ◽  
Antioxidant Defenses ◽  
Free Radical Scavengers ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Nuclear Factor ◽  
Radical Scavengers ◽  
Oxygenation Level

Flavanones are a group of flavonoids that derive from their immediate chalcone precursors through the action of chalcone isomerase enzymes. The Aromatic A and B rings, C4-keto group, and the 15-carbon flavonoid skeleton are all evident in flavanones, but a notable absence of C2-C3 double bond and a lack of oxygenation at C-3 position of the C-ring makes them distinctively different from other groups such as flavonols (e.g., quercetin). On the basis of oxygenation level in the B ring, flavanones can vary from each other as exemplified by pinocembrin (no oxygenation), naringenin (4′-hydroxyl), or eriodictyol (3′,4′-dihydroxyl substitution). These groups are generally weaker free radical scavengers as compared to quercetin and derivatives though eriodictyol has a better free radical scavenging profile within the group due to the presence of the catechol functional moiety. In this communication, their antioxidant potential through the induction of antioxidant defenses is scrutinized. These compounds as exemplified by pinocembrin could induce the nuclear factor erythroid 2-related factor 2- (Nrf2-) heme oxygenase-1 (HO-1) axis leading to amelioration of oxidative stress in cellular and animal models. Their neuroprotective effect through such mechanism is discussed.

Synthesis, Characterization and Antioxidant Activity of Cooper-Quercetin Complex and Iron-Quercetin Complex

2018 ◽  
Vol 69 (10) ◽  
pp. 2621-2624
Author(s):  
Svetlana Trifunschi ◽  
Melania Florina Munteanu
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Radical Scavenging ◽  
Free Radical Scavengers ◽  
Spectroscopic Techniques ◽  
Dpph Radical ◽  
Radical Scavengers ◽  
Therapeutic Applications ◽  
Flavonoid Quercetin ◽  
Dpph Radical Scavenging

Complexes of cooper (II) and iron (II) with flavonoid quercetin have been synthesized. The structure of compounds has been confirmed by means of UV-Vis and FTIR spectroscopic techniques. The antioxidant activity of the flavonoid complexes has been evaluated by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. These complexes of flavonoids are much more effective free radical scavengers than the free flavonoids, an aspect which recommends them for further studies on possible therapeutic applications.

Cyclodextrin encapsulated monometallic and inverted core–shell bimetallic nanoparticles as efficient free radical scavengers

2016 ◽  
Vol 40 (2) ◽  
pp. 1396-1402 ◽  
Author(s):  
Vinod Ishwarbhai Bhoi ◽  
Santosh Kumar ◽  
Chivukula Narayana Murthy
Keyword(s):  
Free Radical ◽  
Au Nanoparticles ◽  
Bimetallic Nanoparticles ◽  
Radical Scavenging ◽  
Free Radical Scavengers ◽  
Core Shell ◽  
Radical Scavengers ◽  
Stabilizing Agent ◽  
Green Route

A facile and green route for monometallic and core–shell bimetallic Ag and Au nanoparticles using cyclodextrin as reducing and stabilizing agent for radical scavenging.

Free Radical Scavengers and Antioxidants from Tagetes mendocina

2004 ◽  
Vol 59 (5-6) ◽  
pp. 345-353 ◽  
Author(s):  
Guillermo Schmeda-Hirschmann ◽  
Alejandro Tapia ◽  
Cristina Theoduloz ◽  
Jaime Rodríguez ◽  
Susana López ◽  
...  
Keyword(s):  
Free Radical ◽  
Superoxide Anion ◽  
Radical Scavenging ◽  
Lung Fibroblasts ◽  
Free Radical Scavengers ◽  
Total Phenolic ◽  
Antioxidant Compounds ◽  
Radical Scavenger ◽  
Radical Scavengers ◽  
Crude Drug

Tagetes mendocina (Asteraceae) is a medicinal plant widely used in the Andean provinces of Argentina. Preliminary assays showed free radical scavenging activity in the methanol extract of the aerial parts, measured by the decoloration of a methanolic solution of the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and scavenging of the superoxide anion. Assayguided isolation led to 4′-hydroxyacetophenone (1), protocatechuic acid (2), syringic acid (3), patuletin (4), quercetagetin 7-O-β-d-glucoside (5), patuletin 7-O-β-d-glucoside (6) and axillarin 7-O-β-d-glucoside (7) as the free radical scavengers and antioxidant compounds from Tagetes mendocina. On the basis of dry starting material, the total phenolic content of the crude drug was 3.00% with 0.372% of flavonoids. The content of compounds 1-7 in the crude drug was 0.008, 0.015, 0.010, 0.029, 0.238, 0.058 and 0.017%, respectively. Quercetagetin 7-O-β-d-glucoside proved to be the main free radical scavenger of the extracts measured by the DPPH decoloration test as well as for quenching the superoxide anion and inhibition of lipoperoxidation in erythrocytes. In the lipid peroxidation assay the percentual inhibition was related with the number of methoxy groups in the molecule, ranging from 86% for the quercetagetin glucoside to 67% for the monomethoxylated and 31% for the dimethoxylated derivative. The compounds showed low cytotoxicity towards human lung fibroblasts with IC50 > 1mᴍ for compounds 1-3 and 0.24 to 0.52 mm for the flavonoids 4-7.

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