Determination of Instinct Components of Biomass on the Generation of Persistent Free Radicals (PFRs) as Critical Redox Sites in Pyrogenic Chars for Persulfate Activation

2021 ◽  
Author(s):  
Wei Wu ◽  
Shishu Zhu ◽  
Xiaochen Huang ◽  
Wei Wei ◽  
Chao Jin ◽  
...  
Keyword(s):  
Free Radicals ◽  
Redox Sites ◽  
Persulfate Activation

Comparative Evaluation of Onion Germplasm (Allium Cepa L.) Of Bangladesh for Physical And Antioxidant Properties

2021 ◽  
Vol 19 (1) ◽  
pp. 113-123
Author(s):  
PK Dash ◽  
S Das ◽  
MA Mannan ◽  
M Jahan
Keyword(s):  
Free Radicals ◽  
Antioxidant Properties ◽  
Biological Properties ◽  
Physicochemical Analysis ◽  
The Other ◽  
Antioxidant Compounds ◽  
Visual Methods ◽  
Ic50 Value ◽  
Onion Germplasm

Determination of antioxidant activity is one of the key elements for understanding the biological properties of a widely used spice onion (A. cepa). In contrast, physical properties help understand the textural quality of onion necessary for postharvest operations of sorting and grading in particular. Considering the physicochemical importance of onion, the present study focused on the determination of physical attributes and antioxidant content of the onion germplasm in Bangladesh using visual methods and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The five-onion germplasms (BARI Piaz-2, BARI Piaz-3, BARI Piaz-4, BARI Piaz-5, Faridpuri Vati) collected from selected onion growers of the Department of Agricultural Extension (DAE) of the southwestern part of Bangladesh were used as treatments for physicochemical analysis at the Horticulture laboratory of the Agrotechnology Discipline, Khulna University, Khulna, Bangladesh during the period from February to August 2019. The laboratory study was laid out in Completely Randomized Design (CRD) with three replications. Most of the physical characteristics of onion were highest in germplasm-1 than those of the other germplasm tested. The results showed that the DPPH free radicals were scavenged by all onion germplasm extracts in a concentration-dependent pattern. The highest IC50 value (238.10 ppm) was noticed in germplasm-3 and the lowest in germplasm-5 (161.29 ppm) with no statistical difference from germplasm-4 (172.41 ppm). The lower IC50 value indicating that onion germplasms-5 and -4 extracts were more potent in scavenging free radicals than the other onion germplasms. Thus, the low IC50 value facilitated the germplasm-5 and -4 to be enriched with antioxidant compounds significantly in higher amounts than the others. SAARC J. Agric., 19(1): 113-123 (2021)

scholarly journals Comparison of free radicals in blood in pre-operative and post-operative phases of breast malignancies: a clinicopathological study

2019 ◽  
Vol 7 (1) ◽  
pp. 210
Author(s):  
Abhishek Jina ◽  
U. C. Singh
Keyword(s):  
Breast Cancer ◽  
Free Radicals ◽  
Breast Carcinoma ◽  
Ductal Carcinoma ◽  
Lipid Peroxide ◽  
P Value ◽  
Breast Cancer Patients ◽  
Medical College ◽  
Surgery Department

Background: Various factors have been identified as influencing factors of breast cancer. The free radicals can cause increased oxidative stress by negatively affecting the body’s nucleic acids, lipids and proteins leading to various illnesses including cancer. Therefore, this study was aimed at discovering the progress of treatment of breast carcinoma by exploring the connections of the disease with free radical injury.Methods: The present study was conducted among 30 breast carcinoma patients received in the surgery department of BRD Medical College Gorakhpur. Determination of the levels superoxide dismutase (SOD) (the procedure of photoluminescence), catalase (method of Cavarochi) and the lipid peroxidise was done. The results were presented as mean and standard error (SE). P value of <0.05 was considered as statistically significant.Results: Among the total participants, 73% patients had infiltrating ductal carcinoma and 27% patients had intraductal carcinoma. The dismutase levels showed an increase in the post-operative patients for both the groups. The catalase levels and the lipid peroxide levels showed a reduction in the postoperative patients (p<0.05).Conclusions: The present study result showed that the low amounts of SOD and catalase may not be sufficient to detoxify high amounts of free radicals. The administration of catalase could help in reducing the symptoms. Though, low amounts of SOD and catalase may not be sufficient to detoxify high amounts of free radicals. The administration of enzymes could help in the treatment of breast cancer patients.

scholarly journals Concentration of hepatic vitamins A and E in rats exposed to chlorpyrifos and/or enrofloxacin

2016 ◽  
Vol 19 (2) ◽  
pp. 371-378 ◽  
Author(s):  
A. Spodniewska ◽  
D. Barski
Keyword(s):  
Lipid Peroxidation ◽  
Free Radicals ◽  
Gastric Tube ◽  
Initial Period ◽  
Hplc Method ◽  
Antioxidant Vitamin ◽  
Exposure Group ◽  
Group Iii ◽  
Group I

Abstract The aim of the study was to determine the level of antioxidant vitamins A and E in the liver of rats exposed to chlorpyrifos and/or enrofloxacin. Chlorpyrifos (Group I) was administered at a dose of 0.04 LD50 (6 mg/kg b.w.) for 28 days, and enrofloxacin (Group II) at a dose of 5 mg/kg b.w. for 5 consecutive days. The animals of group III were given both of the mentioned above compounds at the same manner as groups I and II, but enrofloxacin was applied to rats for the last 5 days of chlorpyrifos exposure (i.e. on day 24, 25, 26, 27 and 28). Chlorpyrifos and enrofloxacin were administered to rats intragastrically via a gastric tube. The quantitative determination of vitamins was made by the HPLC method. The results of this study indicated a reduction in the hepatic concentrations of vitamins A and E, compared to the control, which sustained for the entire period of the experiment. The four-week administration of chlorpyrifos to rats resulted in a significant decrease of vitamins in the initial period of the experiment, i.e. up to 24 hours after exposure. For vitamin A the maximum drop was observed after 24 hours (19.24%) and for vitamin E after 6 hours (23.19%). Enrofloxacin caused a slight (3-9%) reduction in the level of the analysed vitamins. In the chlorpyrifos-enrofloxacin co-exposure group reduced vitamins A and E levels were also noted, but changes in this group were less pronounced in comparison to the animals intoxicated with chlorpyrifos only. The decrease in the antioxidant vitamin levels, particularly noticeable in the chlorpyrifos- and the chlorpyrifos combined with enrofloxacin-treated groups, may result not only from the increase in the concentration of free radicals, but also from the intensification of the secondary stages of lipid peroxidation.

scholarly journals New Methodologies for Qualitative and Semi-Quantitative Determination of Carbon-Centered Free Radicals in Cigarette Smoke Using Liquid ChromatographyTandem Mass Spectrometry and Gas Chromatography-Mass Selective Detection

2010 ◽  
Vol 24 (2) ◽  
pp. 58-71 ◽  
Author(s):  
AR Gerardi ◽  
WM Coleman
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Free Radicals ◽  
Cigarette Smoke ◽  
Selective Detection ◽  
Selected Ion Monitoring ◽  
Relative Quantitation ◽  
Liquid Chromatography Tandem Mass ◽  
New Methodologies

AbstractSeveral approaches were explored to develop a high throughput procedure for relative determination of 14 different carbon-centered free radicals, both acyl and alkylaminocarbonyl type, in cigarette smoke. Two trapping procedures using 3-cyano-2,2,5,5-tetramethyl-1-pyrrolidinyloxy, or 3-cyanoproxyl radical (3-CNP) were designed for this study: a) trapping in solution and b) trapping on a solid support which was a Cambridge filter pad. Fresh whole smoke and vapor phase smoke from mainstream cigarette smoke from Kentucky Reference Cigarettes 2R4F, as partitioned via an unadulterated Cambridge filter pad, were transferred into each trapping system in separate experiments. The 3-CNP coated Cambridge filter pad approach was shown to be superior to the impinger procedure as described in this study. Gas chromatography coupled with mass selective detection (GC-MS) was employed for the first time as an alternate means of detecting several relatively highly concentrated radical adducts. Liquid chromatography tandem mass spectrometry (LC-MS/MS) with precursor ion monitoring and selected ion monitoring (SIM) was used for detecting the large array of radicals, including several not previously reported: formyl, crotonyl, acrolein, aminocarbonyl, and anilinocarbonyl radicals. Relative quantitation was achieved using as external calibration standards of 4-(1-pyrrolidino)benzaldehyde and nicotine. It was determined that the yield of carbon-centered free radicals by reference cigarette 2R4F was approximately 265 nmoles/cigarette at 35 mL puff/60 sec interval/2 sec duration smoking conditions.

DISPOSABLE SCREEN PRINTED POTENTIOMETRIC SENSORS FOR DETERMINATION OF FREE RADICALS

2002 ◽  
Author(s):  
L. CAMPANELLA ◽  
G. FAVERO ◽  
S. MARINO ◽  
R. PILLOTON ◽  
M. TOMASSETTI
Keyword(s):  
Free Radicals ◽  
Potentiometric Sensors ◽  
Screen Printed

Enhancement of carboxylic acid degradation with sulfate radical generated by persulfate activation

2010 ◽  
Vol 61 (5) ◽  
pp. 1221-1226 ◽  
Author(s):  
J. Criquet ◽  
P. Nebout ◽  
N. Karpel Vel Leitner
Keyword(s):  
Aqueous Solution ◽  
Citric Acid ◽  
Carboxylic Acids ◽  
Sulfate Radical ◽  
Acid Degradation ◽  
Competitive Reactions ◽  
Radical Production ◽  
Persulfate Activation ◽  
Kinetics Of

The aim of this work was to investigate the generation of sulfate radical for the removal of two carboxylic acids in aqueous solution: acetic and citric acids. From photochemical and radiolytic processes, kinetics of the degradation of these two carboxylic acids was studied as a function of the pH of the solution. It was shown that the maximum of acetic acid degradation occurred at pH 5. Above this pH, competitive reactions with the carbon mineralized inhibit the reaction of with the solute. In the case of citric acid, pH has only a little effect on the kinetic of citric acid degradation. The determination of mineralization yields shows several differences depending on carboxylic acids and pH. The degradation of both carboxylic acids was also studied in the radiolysis process whether with or without persulfate addition. A comparison of the processes of sulfate radical production is presented.

The Action of Unsaturated Compounds on Natural Rubber in Solution. II. The Reaction Induced by Heat Alone

1952 ◽  
Vol 25 (2) ◽  
pp. 275-286
Author(s):  
André Delalande
Keyword(s):  
Free Radicals ◽  
Elevated Temperature ◽  
Natural Rubber ◽  
Addition Reaction ◽  
Thermal Reaction ◽  
Temperature Range ◽  
Unsaturated Compounds ◽  
Mechanism Of The Reaction

Abstract The addition reaction at an elevated temperature (170° C) of maleic N-methylimide with natural rubber in solution was studied. Attempts were made to apply the principles of kinetics to this thermal reaction with a view to understanding the nature of the reaction, but the complexity of the system made impossible any chance of attaining the results hoped for. A comparison of the fixation of acrylonitrile and that of maleic N-methylimide in the temperature range of 160°–200° C showed that the rates of these two reactions are in the ratio of 1 to 25–30. A determination of the unsaturation of the addition products showed that fixation is on the α-methylenic carbon atoms of the rubber hydrocarbon. Finally a mechanism of the reaction is proposed, in which free radicals play a part.

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