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Author(s):  
N’Negue Mezui-Mbeng MA ◽  

Introduction: The oxidative stress and the deterioration of the antioxidant system demonstrated by the dosage of antioxidant enzymes and the by-products of lipid peroxidation are involved in the occurrence of uterine myomas. Objectives: To measure the antioxidant activity of the plasma of patients with uterine myoma and that of the plasma of their age-matched controls by trapping the free radical ABTS+. The study aims to confirm by another assessment technique. Results: The anti-free radical activities of the plasmas of patients with myomas and those of their respective controls vary from 1.3 to 6%. In addition, two cases were observed: either the anti-radical activity of the control subjects turned out to be slightly higher than that of the patients; or the anti-free radical activity of patients with uterine myomas was slightly stronger than those of their controls. In addition, our results showed that the anti-free radical activity of patients aged over 40 years is slightly higher than that of patients aged less than or equal to 40 years. Finally, the anti-free radical activity decreases with an increase in BMI and increases with the number of gestities and parity. Conclusion: Assessment of the total antioxidant capacity of blood by trapping the ABTS+ radical can be used to assess, at a certain threshold, the oxidative stress involved in the development of uterine myoma. This method can also be used to assess the effect of age, BMI, pregnancy and parity on the occurrence of myomas.


Author(s):  
Wei-Hsun Wang ◽  
Wei-Lin Li ◽  
Cheng-You Chen ◽  
Min-Yun Chang ◽  
Shu-Ling Huang ◽  
...  

Abstract Background Chenopodium formosanum (CF) provides the human body with numerous nutritional components. This study used the two-phase system to identify an efficient method to obtain CF extracts. CF extraction was performed using an ethanol–ammonium sulfate two-phase system. The efficacy of different CF extracts with five types of antioxidant ability was tested and compared with traditional aqueous and alcohol extractions. Results The results showed that a separated top of the two-phase system extract had higher total phenol content (120.35 ± 5.80 mg gallic acid equivalent/g dry extract), total flavonoid content (447.06 ± 16.57 mg quercetin equivalent/g dry extract) and reducing ability (284.48 ± 4.60 mg vitamin C equivalent/g dry extract) than those of other extracts. Furthermore, the separated top of the two-phase system extract and the top of the two-phase system extract had higher 1,1-diphenyl-2-picrylhydrazyl free radical scavenging ability and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radical scavenging ability than those of the water extract, alcohol extract, bottom of two-phase system extract, and separated bottom of two-phase system extract. Conclusions The results indicate that CF has great potential for use in natural plant health supplements and skin care products and that the two-phase extraction system can yield an effective CF extract. Graphical Abstract


2022 ◽  
Vol 8 (1) ◽  
pp. 192-199
Author(s):  
Mahesh Kumar D

Background: Silver Nanoparticles are drawing significant attention from the scientific community to explore a wide range of its medical applications. Human body is under constant stress due to free radicals generated by the physiological and pathological conditions in the body. Scavenging systems or Antioxidants can help alleviate the damages caused by these radicals which can influence the course of progress in several chronic diseases with an inflammatory background. External antioxidants supplement and facilitate the overwhelmed scavenging systems in the body.Silver Nanoparticles can enhance the therapeutic effects of phytochemicals. Aim: To Synthesize silver nanoparticles using the phytochemical Hesperidin and studying its Free radical scavenging activity. Methods: Silver Nanoparticles are synthesized using chemical reduction method. The synthesis is confirmed using spectrophotometric studies. Free Radical scavenging activity is detected using 1, 1-diphenyl-2-picrylhydrazyl (DPPH •) free radical scavenging assay. Results: Silver nanoparticles were successfully synthesized which was confirmed by the change in color of the solution and peak absorbance peak at 420 nM on spectrophotometric studies.Hesperidin Silver Nanoparticles exhibited higher free radical scavenging activity when compared with pure hesperidin and standard Ascorbic acid. Conclusion: Hesperidin can ideally be used for the synthesis of silver nanoparticles and the synthesized Silver Nanoparticles enhances the free radical scavenging activity of Hesperidin which can further be evaluated by In Vivo studies.


Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 506
Author(s):  
Jie Lu ◽  
Zhiqiang Huang ◽  
Yusheng Liu ◽  
Huimin Wang ◽  
Min Qiu ◽  
...  

Flavonoids have important biological activities, such as anti-inflammatory, antibacterial, antioxidant and whitening, which is a potential functional food raw material. However, the biological activity of Fengdan peony flavonoid is not particularly clear. Therefore, in this study, the peony flavonoid was extracted from Fengdan peony seed meal, and the antioxidant, antibacterial and whitening activities of the peony flavonoid were explored. The optimal extraction conditions were methanol concentration of 90%, solid-to-liquid ratio of 1:35 g:mL, temperature of 55 °C and time of 80 min; under these conditions, the yield of Fengdan peony flavonoid could reach 1.205 ± 0.019% (the ratio of the dry mass of rutin to the dry mass of peony seed meal). The clearance of Fengdan peony total flavonoids to 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl radical and 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical could reach 75%, 70% and 97%, respectively. Fengdan peony flavonoid could inhibit the growth of the Gram-positive bacteria. The minimal inhibitory concentrations (MICs) of Fengdan peony flavonoid on S. aureus, B. anthracis, B. subtilis and C. perfringens were 0.0293 mg/mL, 0.1172 mg/mL, 0.2344 mg/mL and 7.500 mg/mL, respectively. The inhibition rate of Fengdan peony flavonoid on tyrosinase was 8.53–81.08%. This study intensely illustrated that the antioxidant, whitening and antibacterial activity of Fengdan peony total flavonoids were significant. Fengdan peony total flavonoids have a great possibility of being used as functional food materials.


2022 ◽  
Vol 6 (2) ◽  
pp. 01-06
Author(s):  
Prince N. Agbedanu ◽  
Troy B. Puga ◽  
Joshua Schafer ◽  
Pearce Harris ◽  
Gary Branum ◽  
...  

1. Aim/Background: Reactive oxygen species (ROS) have been identified as compounds responsible for producing cellular damage. The purpose of this research is to examine if there is production of reactive oxygen species through free radical intermediates within human hepatocytes treated with morphine, bilirubin, or furosemide. The investigation examines the early stages of biotransformation by measuring the levels of reactive oxygen species produced inside of the treated hepatocytes within the first and second hours of treatment. The experiment was designed upon a case of a jaundiced (elevated bilirubin) infant who received morphine and furosemide and later died through unknown mechanisms. The experiment looks to examine if these drug compounds could contribute to cellular damage. This can help to further understand the potential interactions and complications of free radical intermediates produced during the phases of biotransformation. 2. Method: Previously cultured human hepatocytes were washed by centrifugation and re-suspended in 1x supplemental buffer to a concentration of 1x106 cells/mL and seeded in a dark clear bottom 96-well microplate at 100,000 stained cells/well. The cells were treated with either furosemide, morphine, bilirubin, a Tert-Butyl hydro peroxide (TBHP) positive control, or left as a background. Reactive oxygen generated in the presence of these agents were quantified by fluorescence excitation/emission measurement at 495nm/529nm. Fluorescence was measured at one and two hours. ROS generated convert 2',7'-dichlorodihydrofluorescein diacetate to 2',7'-dichlorodihydrofluorescein within the cells, which fluoresces. The fluorescence intensity detected is equivalent to the level of ROS generated. Wells that were untreated were used as blanks and subtracted from background and TBPH. 3. Results: Furosemide and Morphine did not produce statistically significant levels of ROS (p >0.05) above the background in both hours 1 and 2 of biotransformation and ROS measurement (Figure 1). Although Bilirubin did not produce statistically significant (p >0.05) levels of ROS above the background (Figure 2) during the first hour, it did produce statistically significant levels in the second hour of biotransformation. Each compound’s level of ROS was reduced during the second hour, signaling the removal of intermediate ROS metabolites (Figure 2). The production of ROS in each compound signifies that there is biotransformation to an intermediate that produces ROS. 4. Conclusion: The production of ROS above the background by each of the compounds shows there is an intermediate free radical compound that is produced during the biotransformation of each compound [21]. In this study, although furosemide and morphine did not produce statistically significant levels of ROS in both hours of biotransformation, bilirubin did produce significant levels of ROS in the second hour of biotransformation. This finding is in line with previous studies that shows morphine to offer protective effects against ROS production [16, 17]; and bilirubin demonstrating deleterious production of ROS at high doses [18]. Further work must be done to examine the correlation between the levels of ROS and extent of hepatocellular damage.


2022 ◽  
Author(s):  
Tamara Erceg ◽  
Gaja Brakus ◽  
Alena Stupar ◽  
Miroslav Cvetinov ◽  
Miroslav Hadnađev ◽  
...  

Abstract The paper presents the synthesis of hydrogels via free-radical polymerization, based on Chitosan (CS) grafted with Acrylic acid (AA), using a two-step procedure. Free-radical polymerization has given strong hydrogels with compact structure, dominant elastic behavior and long linear viscoelastic region. The results of rheological studies have shown that obtained hydrogels have significantly improved mechanical properties in comparison to chitosan hydrogels obtained by other sustainable methods. A step forward in the investigation of the potential application of chitosan hydrogels in wound dressing systems has been made by preparation of the bilayer design by embedding a layer of active compound-loaded alginate beads into the contact surface between two conjoined units of CS/AA hydrogels. Wild garlic (Allium ursinum L.) dried extract was used as an active compound because of its antimicrobial activity and green properties. This system has demonstrated pH-dependent release of extract and higher shear elastic modulus values than ordinary disc gels. A conducted study has given preliminary results for the possible application of bilayer chitosan - based hydrogels in wound dressing systems and represents the first step towards extrapolating the proposed design across other application fields.


Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 282
Author(s):  
Maria Simonova ◽  
Denis Kamorin ◽  
Anton Sadikov ◽  
Alexander Filippov ◽  
Oleg Kazantsev

Thermo- and pH-responsive poly(N-[3-(diethylamino)propyl]methacrylamide)s were synthesized by free radical polymerization and RAFT polymerization. The molar masses of the samples were 33,000–35,000 g∙mol−1. Investigations of the dilute solutions showed that the prepared samples were flexible chain polymers. The behavior of the synthesized polymers in the buffer solutions was analyzed by turbidity and light scattering at a pH range of 7–13 and a concentration range of 0.0002–0.008 g·cm−3. When the concentrated solutions were at a low temperature, there were macromolecules and aggregates, which were formed due to the interaction of hydrophobic units. For the investigated samples, the lower critical solution temperatures were equal. The phase separation temperatures decreased as pH increased. The influence of polydispersity index on the characteristics of the samples in the solutions was analyzed. The radii of molecules of poly(N-[3-(diethylamino)propyl]methacrylamide) obtained by RAFT polymerization at this temperature at the onset and end of the phase separation interval were lower than ones for samples synthesized by conventional free radical polymerization.


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