Oxidative stress and free radicals

2003 ◽  
Vol 666-667 ◽  
pp. 387-392 ◽  
Author(s):  
Svend J.Knak Jensen
Keyword(s):  
Oxidative Stress ◽  
Free Radicals

UJI AKTIVITAS ANTIOKSIDAN FRAKSI N-HEKSAN DAUN AFRIKA (Vernonia amygdalina Del.) DENGAN METODE DPPH

2020 ◽  
Vol 5 (2) ◽  
pp. 250-257
Author(s):  
Nurul Fatimah ◽  
◽  
Reksi Sundu
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Activity ◽  
Free Radicals ◽  
Ethanolic Extract ◽  
Ethanol Extract ◽  
Hexane Fraction ◽  
Phytochemical Screening ◽  
Vernonia Amygdalina ◽  
Tropical Africa ◽  
Ic50 Value

Free radicals and reactive species are widely believed to contribute to the development of several diseases by causing oxidative stress and eventually oxidative. Vernonia amygdalina (Astereacea) is a small shrub or tree between 1 and 5m high growing throughout tropical Africa. Plants are generally known as bitter leaves is well cultivated and is a general market for merchandise in several countries. The purpose of this study was to determine the antioxidant activity of hexane fraction from ethanol extract od Frican leaves (Vernonia amygdalina Del.). The method used in this study was the DPPH (1,1-Diphenil-2-Picrylhydrazyl) method. The result of phytochemical screening showed that ethanolic extract of African leaves contained a composition of secondary metabolites of alkaloids, flavonoids, tannins, steroids/triterpenoids and saponins. The antioxidant activity of the extract of n-hexane fraction was classified as very weak with an IC50 value of 317.98 ppm.

Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Male Smokers

2019 ◽  
Vol 22 (7) ◽  
pp. 496-501
Author(s):  
Fatemeh Ahmadi-Motamayel ◽  
Parisa Falsafi ◽  
Hamidreza Abolsamadi ◽  
Mohammad T. Goodarzi ◽  
Jalal Poorolajal
Keyword(s):  
Oxidative Stress ◽  
Uric Acid ◽  
Free Radicals ◽  
Antioxidant Capacity ◽  
Cigarette Smoke ◽  
Total Antioxidant Capacity ◽  
The Body ◽  
Total Antioxidant ◽  
The Mean ◽  
And Oxidative Stress

Background: Cigarette smoke free radicals can cause cellular damage and different diseases. All the body fluids have antioxidants which protect against free radicals. Objective: The aim of this study was to evaluate salivary total antioxidant capacity and peroxidase, uric acid and malondialdehyde levels in smokers and a nonsmoking control group. Methods: Unstimulated saliva was collected from 510 males. A total of 259 subjects were current smokers and 251 were non-smokers. The levels of salivary total antioxidant capacity, uric acid, peroxidase and malondialdehyde were measured using standard procedures. Data were analyzed with t test and ANOVA. Results: The smokers were younger and dental hygiene index was higher than healthy nonsmoking controls. The mean total antioxidant capacity in smokers and nonsmokers was 0.13±0.07 and 0.21±011, respectively (P=0.001). Smokers had significantly lower peroxidase and uric acid levels than healthy controls. In addition, the mean malondialdehyde levels in the smokers and nonsmokers were 4.55 ±2.61 and 2.79 ±2.21, respectively (P=0.001). Conclusion: Cigarette smoke produces free radical and oxidative stress, causing many side effects. Salivary antioxidant levels decreased and malondialdehyde levels increased in smokers, indicating the high oxidative stress among smokers compared to nonsmokers. Cigarette smoke had deleterious effects on main salivary antioxidants levels.

scholarly journals Malondialdehyde levels can be measured in serum and saliva by using a fast HPLC method with visible detection / Determinarea printr-o metodă HPLC-VIS rapidă a concentraţiilor serice şi salivare ale malondialdehidei

2016 ◽  
Vol 24 (3) ◽  
pp. 319-326 ◽  
Author(s):  
Erzsébet Fogarasi ◽  
Mircea Dumitru Croitoru ◽  
Ibolya Fülöp ◽  
Enikő Nemes-Nagy ◽  
Robert Gabriel Tripon ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Free Radicals ◽  
Unsaturated Fatty Acids ◽  
Pearson Correlation ◽  
Living Organism ◽  
Hplc Method ◽  
Limit Of Quantification ◽  
Pearson Correlation Test ◽  
Repeated Sample

Abstract Oxidative stress appears when the amount of free radicals that are formed in a living organism exceed its spin-trapping ability. One of the most dangerous free radicals that are formed in the human body is the hydroxyl radical. It can alter several biomolecules, including the unsaturated fatty acids; this process is known as lipid peroxidation and can lead to cell necrosis and generation of several harmful byproducts including malondialdehyde, which serves also as a biomarker of oxidative stress. A new HPLC method with visible detection was developed for the detection of malondialdehyde in human serum and saliva samples. The method was verified in terms of specificity, linearity, limits of detection (0.35 ng/ml), limit of quantification (1.19 ng/ml), recovery (90.13±10.25 – 107.29±14.33) and precision (3.84±1.49% – 6.66±1.76%). An analysis time of only 1 minute was obtained and no interferences from the matrices were observed. Statistical analysis (Pearson correlation test) showed a moderate correlation (R = 0.5061, p = 0.0099) between serum and saliva concentrations (N = 25). The possibility of measuring salivary concentrations of malondialdehyde extents the applications of oxidative stress/lipid peroxidation estimations to categories of population unreachable before (pregnant women, small children, etc); repeated sample studies are also easier to make.

scholarly journals Mechanistic Insight into Antimicrobial and Antioxidant Potential of Jasminum Species: A Herbal Approach for Disease Management

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1089
Author(s):  
Acharya Balkrishna ◽  
Akansha Rohela ◽  
Abhishek Kumar ◽  
Ashwani Kumar ◽  
Vedpriya Arya ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Drug Resistance ◽  
Free Radicals ◽  
Free Radical ◽  
Microbial Pathogens ◽  
Free Radical Scavengers ◽  
Bioactive Constituents ◽  
Global Issues ◽  
Iridoid Glucosides ◽  
Insight Into

Drug resistance among microbial pathogens and oxidative stress caused by reactive oxygen species are two of the most challenging global issues. Firstly, drug-resistant pathogens cause several fatalities every year. Secondly aging and a variety of diseases, such as cardiovascular disease and cancer, are associated with free radical generated oxidative stress. The treatments currently available are limited, ineffective, or less efficient, so there is an immediate need to tackle these issues by looking for new therapies to resolve resistance and neutralize the harmful effects of free radicals. In the 21st century, the best way to save humans from them could be by using plants as well as their bioactive constituents. In this specific context, Jasminum is a major plant genus that is used in the Ayurvedic system of medicine to treat a variety of ailments. The information in this review was gathered from a variety of sources, including books, websites, and databases such as Science Direct, PubMed, and Google Scholar. In this review, a total of 14 species of Jasminum have been found to be efficient and effective against a wide variety of microbial pathogens. In addition, 14 species were found to be active free radical scavengers. The review is also focused on the disorders related to oxidative stress, and it was concluded that Jasminum grandiflorum and J. sambac normalized various parameters that were elevated by free radical generation. Alkaloids, flavonoids (rutoside), terpenes, phenols, and iridoid glucosides are among the main phytoconstituents found in various Jasminum species. Furthermore, this review also provides insight into the mechanistic basis of drug resistance, the generation of free radicals, and the role of Jasminum plants in combating resistance and neutralizing free radicals.

Defective Ag-In-S/ZnS Quantum Dots: An Oxygen-derived Free Radicals Scavenger for Mitigating the Macrophage Inflammation

2021 ◽  
Author(s):  
Na Gao ◽  
Jing Jing ◽  
Hengzhi Zhao ◽  
Yazhou Liu ◽  
Chunlei Yang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Quantum Dots ◽  
Heart Disease ◽  
Free Radicals ◽  
Inflammatory Diseases ◽  
Antioxidant Therapy ◽  
Oxygen Derived Free Radicals ◽  
Promising Strategy

Oxidative stress plays an important role in the development of inflammatory diseases including allergy, heart disease, diabetes and cancer. Nanomaterials-mediated antioxidant therapy is regarded as a promising strategy to treat...

scholarly journals Free Radicals, Metal Ions and Oxidative Stress: Chemical Mechanisms of Damage and Protection in Living Systems

1995 ◽  
Vol 6 (3) ◽  
pp. 221-227 ◽  
Author(s):  
G. Rotilio ◽  
L. Rossi ◽  
A. de Martino ◽  
Ana Maria da Costa Ferreira ◽  
M.R. Ciriolo
Keyword(s):  
Oxidative Stress ◽  
Free Radicals ◽  
Metal Ions ◽  
Living Systems ◽  
Chemical Mechanisms ◽  
And Oxidative Stress

scholarly journals Oxidative stress in ageing

2017 ◽  
Vol 5 (11) ◽  
pp. 4826 ◽  
Author(s):  
Fasna K. A. ◽  
Geetha N. ◽  
Jean Maliekkal
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Free Radicals ◽  
Free Radical ◽  
Age Groups ◽  
The Body ◽  
Antioxidant Systems ◽  
Lipid Peroxidation Product ◽  
Free Radical Theory ◽  
Radical Theory

Background: Ageing is characterized by a gradual decline in body functions and decreased ability to maintain homeostasis. The free radical theory of ageing proposed by Harman D states that ageing is a result of cumulative damage incurred by free radical reactions. Free radicals are highly reactive molecular species with unpaired electrons; generated in the body by several physiological processes. Prime target to free radical attack are the polyunsaturated fatty acids of cell membranes causing lipid peroxidation. The free radicals are neutralized by the exogenous and endogenous antioxidant systems. Oxidative stress occurs when large number of free radicals are produced or the antioxidant activity is impaired. The present study is focused to find out the role of oxidative stress in ageing.Methods: A cross sectional observational study was undertaken to assess the oxidative stress in ageing; by determining the levels of lipid peroxidation product- malondialdehyde (MDA), the antioxidants- superoxide dismutase (SOD) and ceruloplasmin in various age groups. 150 healthy subjects were selected randomly and categorised into three different age groups of 20-30 years, 40-59 years and 60-90 years; with 50 subjects in each group. Results were expressed as mean ± standard deviation.Results: a significant elevation in serum MDA level and a decline in SOD were observed in 40-59 years and 60-90 years age groups. However, an elevated ceruloplasmin level was found in the above age groups.Conclusions: Aforementioned observations are suggestive of an association between oxidative stress and the progression of ageing process.

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