Tag Archives: free radicals

Qualitative phytochemical screening and in vitro antioxidant activities of aqueous extracts of Rhaphiolepis bibas (Lour.) Galasso & Banfi

Ibrahim Waweru Kariuki, Mathew Ngugi, John Maingi

Kenyatta University, Nairobi, Kenya

DOI: 10.2478/amma-2024-0022

Reactive oxygen species causes harm to cell membranes and biomolecules, wherefore chronic diseases develop. Antioxidants scavenge such free radicals combating oxidative stress. This research aimed to determine the antioxidant potential of the aqueous stem bark, root and leaf extracts of Rhaphiolepis bibas against standards. DPPH radical scavenging activity was high from th stem bark extract at 72.33% with root extract at 65.85% and leaf extract at 55.91%, while ascorbic acid scavenged 89.53% of DPPH radicals. The leaf extract had the highest H2O2 scavenging activity of 91.92% with stem bark at 91.17% and the root extracts at 89.12%. The aqueous root extract of R. bibas had a significantly higher FRAP capacity in comparison to the leaf extracts and the stem bark. The abilities to chelate iron by the leaf extract were statistically higher compared to the root and stem bark extracts. Stem bark extracts had the highest phenol content of about 149.44 followed by the root extract at 141.14 and the least amount of phenol was found in the aqueous leaf extract having 73.012 Gallic acid equivalent/g. The root extracts had the highest total flavonoid 377.66-milligram quercetin equivalent/gram dry weight followed by stem bark extract at 255.72 and the least amount was found in aqueous leaf extract having 164.52 mgQE/g of sample dry weight. The existence of secondary metabolites linked to antioxidant action was shown by the qualitative phytochemical screening.

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Volemic resuscitation in a patient with multiple traumas and haemorrhagic shock. Anti-oxidative therapy management in critical patients. A Case Report

Bedreag Ovidiu Horea1,2, Rogobete Alexandru Florin1,2*, Sarandan Mirela3, Cradigati Alina Carmen3, Nartita Radu1, Sandesc Dorel1,2, Papurica Marius1,2

1 Clinic of Anaesthesia and Intensive Care, Emergency County Hospital ”Pius Brinzeu”, Timisoara, Romania
2 Faculty of Medicine, ”Victor Babes” University of Medicine and Pharmacy, Timisoara, Romania
3 Clinic of Anaesthesia and Intensive Care ”Casa Austria”, Emergency County Hospital ”Pius Brinzeu”, Timisoara, Romania

DOI: 10.1515/amma-2016-0002

A patient with multiple traumas is usually found in severe haemorrhagic shock. In 40% of the cases, the patient with multiple traumas and haemorrhagic shock cannot recover due to secondary injuries and complications associated with the shock. In this paper we present the case of a male patient 30 years old, who suffered a car accident. The patient is admitted in our hospital with haemorrhagic shock due to femur fracture, acute cranial-cerebral trauma and severe thoracic trauma with bleeding scalp wound, associated with lethal triad of trauma. The clinical and biological parameters demand massive transfusion with packed red blood cells (PRBCs), fresh frozen plasma (FFP), cryoprecipitate (CRY) and colloidal solution (CO) sustained with vassopresor for the haemodynamic stabilisation. During his stay in the ICU, the patient benefits from anti-oxidative therapy with Vitamin C, Vitamin E and Vitamin B1. After 14 days the clinical state of the patient improves and he is transferred in Polytrauma Department.

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Is the Oxidative Stress Really a Disease?

Fogarasi Erzsébet1, Croitoru Mircea Dumitru1*, Fülöp Ibolya1, Muntean Daniela-Lucia2

1 Department of Toxicology and Biopharmacy, University of Medicine and Pharmacy Tîrgu Mureș, Romania
2 Analytical chemistry and analysis of medicines, University of Medicine and Pharmacy Tîrgu Mureș, Romania

DOI: 10.1515/amma-2015-0070

Oxidative stress is an imbalance between free radicals or other reactive species and the antioxidant activity of the organism. Oxidative stress can induce several illnesses such as cardiovascular disease, neurodegenerative disorders, diabetes, cancer, Alzheimer and Parkinson. The biomarkers of oxidative stress are used to test oxidative injury of biomolecules. The indicators of lipid peroxidation (malondialdehyde, 4-hydroxy-2-nonenal, 2-propenal, isoprostanes), of protein oxidation (carbonylated proteins, tyrosine derivatives), of oxidative damage of DNA, and other biomarkers (glutathione level, metallothioneins, myeloperoxidase activity) are the most used oxidative stress markers. Diseases caused by oxidative stress can be prevented with antioxidants. In human body are several enzymes with antioxidant capacity (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase) and spin traps. Antioxidants are synthetized in the organism (glutathione) or arrive in the body by nutrition (ascorbic acid, vitamin E, carotenoids, flavonoids, resveratrol, xanthones). Different therapeutic strategies to reduce oxidative stress with the use of synthetic molecules such as nitrone-based antioxidants (phenyl-α-tert-butyl-nitrone (PBN), 2,4-disulphophenyl-N-tert-butylnitrone (NXY-059), stilbazulenyl nitrone (STAZN)), which scavenge a wide variety of free radical species, increase endogenous antioxidant levels and inhibits free radical generation are also tested in animal models.

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