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

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.

scholarly journals PHYTOCHEMICAL SCREENING AND IN VITRO ANTIOXIDANT POTENTIAL OF TRIBULUS TERRESTRIS FRUIT AND MESUA FERREA FLOWER EXTRACTS: A COMPARATIVE STUDY

2018 ◽  
Vol 10 (3) ◽  
pp. 70
Author(s):  
Dakshayini P. N. ◽  
Mahaboob Basha P.
Keyword(s):  
Free Radical ◽  
Radical Scavenging ◽  
Pharmaceutical Products ◽  
Free Radical Scavenging ◽  
Aluminium Chloride ◽  
Free Radical Scavengers ◽  
Total Phenolic ◽  
P Value ◽  
Tribulus Terrestris ◽  
Ethanolic Extracts

Objective: This study aimed to investigate the antioxidants and free radicals scavenging properties of ethanolic extracts from Tribulus terrestris fruit (TTF) and Mesua ferrea flower (MFF).Methods: The antioxidant and free radical scavenging activities were measured by using standard protocols against phytoextracts used at 50, 100, 150, 200 and 250 µg/ml concentration. Total phenolic and flavonoid content were estimated using Folin-Ciocalteu and aluminium-chloride reagent assay methods.Results: Among the extracts, MFF showed the highest total antioxidant ability followed by TTF. With regard to various scavenging activities, MFF had the highest radical scavenging activity than TTF extract closely resembled the standards. Also, the reducing capacity on ferrous ion was high in MFF than TTF. The quantified phenolic contents of TTF and MFF ethanolic extracts were 27.0±0.36 and 57.0±0.32 mg gallic acid equivalent per gram extract respectively. A positive correlation (p value<0.001) was observed between phenolic content and free radical scavenging efficiencies.Conclusion: The results confirm that both MFF and TTF are important sources of natural antioxidants and serves as an effective free radical scavengers and/or inhibitors. Hence, both extracts are suitable plant-based pharmaceutical products can be used to handle 'free radical-mediated diseases.

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.

scholarly journals Bergenin Content and Free Radical Scavenging Activity of Bergenia Extracts

2015 ◽  
Vol 10 (7) ◽  
pp. 1934578X1501000
Author(s):  
Helena Hendrychová ◽  
Jan Martin ◽  
Lenka Tůmová ◽  
Nina Kočevar-Glavač
Keyword(s):  
Free Radical ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Hplc Method ◽  
Free Radical Scavenging ◽  
Free Radical Scavenging Activity ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Scavenging Activity ◽  
Different Seasons

Our research was focused on the evaluation of bergenin content and free radical scavenging activity of extracts prepared from three different species of Bergenia - B. crassifolia (L.) Fritsch., B. ciliata (Haw.) Sternb. and B. x ornata Stein. collected during different seasons. Using an HPLC method, the highest total amount of bergenin was revealed in the leaves of B. x ornata and B. crassifolia (4.9 - 5.1 mg.g−1). Free radical scavenging power was determined by two methods - FRAP and NADH. The best free radical scavengers were B. crassifolia (FRAP: 6.7 - 15.9 mg GAE.100g−1; NADH: 20.3 - 50.9%) and B. ornata (FRAP: 13.7 - 15.2 mg GAE.100g−1; NADH: 29.3 - 31.1%). The lowest content of bergenin and the weakest radical scavenger was B. ciliata (bergenin: 3.1 mg.g−1; FRAP: 5.5 - 11.0 mg GAE.100g−1; NADH: 23.2 - 25.6%). The presence of a large percentage of bergenin is responsible for the radical scavenging activity, as shown by the results from the FRAP and NADH assays. Significant, positive correlation was found between bergenin content and radical scavenging activity in both methods.

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 Discovery of Some Emerging Free Radical Scavenging Candidates Bearing 2-(P-hydroxyphenyl)-4–(Substitutedphenyl)-1H-1,5–Benzodiazepines Pharmacophore

2017 ◽  
Vol 9 (04) ◽  
Author(s):  
Animeshchandra G. M. Haldar ◽  
Santosh S. Chhajed ◽  
Debarshi Kar Mahapatra ◽  
Debarshi Kar Mahapatra
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Analytical Techniques ◽  
Free Radical Scavenging ◽  
Free Radical Scavengers ◽  
Scavenging Activity ◽  
In Vitro Antioxidant Activity

In the present investigation, the synthesis of few novel leads bearing 2-(p-hydroxyphenyl)-4–(substitutedphenyl)-1H-1,5–benzodiazepine pharmacophore is described. The substituted chalcone and their derivatives 3(a-j) were synthesized by base catalyzed Claisen-Schmidt condensation between p-hydroxy-acetophenone and appropriate aldehydes. The dibromostyryl ketones 4(a-j) were obtained by the reaction the chalcone with bromine in acetic acid. The dibromostyryl ketone were reacted with methanol in presence of sodium methoxide followed by acidic hydrolysis give 1-(4-hydroxyphenyl)-3-(substitutedphenyl)-1,3-propanediones. The targeted compounds; the substituted 1,5-benzodiazepines were synthesized with o-phenylenediamine and synthesized 1,3-propanediones. The structures of synthesized compounds were confirmed by spectroscopic and analytical techniques (IR, 1H-NMR, and MS). The free radical scavenging activity of the synthesized analogs was monitored by in vitro antioxidant activity protocol. The derivatives 6f, 6g, 6i, and 6j were found to exhibit good antioxidant activity with 59.07%, 41.33%, 68.3% and 60.4% scavenging activity respectively as compared to standard ascorbic acid which demonstrated 79.73% activity. The current research revealed the potential of 2-(p-hydroxyphenyl)-4–(substituted-phenyl)-1H-1,5–benzodiazepine as emerging free radical scavengers. The study helped to establish a structure-activity relationship (SAR) where the substitution on the phenyl moiety of the 1,5-benzodiazepine was found to play profound role and influence over biological activity. The research will open new avenues for the development of antioxidant moieties having perspectives in cancer, inflammation, and several other ailments.

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.

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