Flavonoids are scavengers of superoxide anions
Abstract
Seven flavonoids and three non-flavonoid antioxidants, i.e. butylated hydroxy anisole, chlorpromazine and BW 755 C, were studied as potential scavengers of oxygen free radicals. Superoxide anions were generated enzymatically in a xanthine-xanthine oxidase system and non-enzymatically in a phenazine methosulphate-NADH system, and assayed by reduction of nitro blue tetrazolium. The generation of malonaldehyde (MDA) by the ascorbate-stimulated air-oxidised boiled rat liver microsomes was considered as an index of the non-enzymatic formation of hydroxyl radicals. Flavonoids but not non-flavonoid antioxidants lowered the concentration of detectable Superoxide anions in both enzymic and non-enzymic systems which generated these SOD-sensitive radicals. The most effective inhibitors of Superoxide anions were quercetin, myricetin and rutin. Four out of seven investigated flavonoids seemed also to suppress the activity of xanthine oxidase as measured by a decrease in uric acid biosynthesis. All ten investigated compounds inhibited the MDA formation by rat liver microsomes. Non-flavonoid antioxidants were more potent MDA inhibitors than flavonoids. It is concluded that antioxidant properties of flavonoids are effected mainly via scavenging of Superoxide anions whereas non-flavonoid antioxidants act on further links of free radical chain reactions, most likely by scavenging of hydroxyl radicals.
References (16)
- R.J. Gryglewski et al.
Prostaglandins
(1976) - L. Cavallini et al.
Pharmac. Res. Commun.
(1978) - J.M. McCord et al.
J. biol. Chem.
(1968) - A. Bindoli et al.
Pharmac. Res. Commun.
(1985) - Z. Duniec et al.
Biochem. Pharmac.
(1983) - G. Cohen et al.
J. biol. Chem.
(1974) - W.W. Busse et al.
J. Allergy clin Immun.
(1984) - C. Pagonis et al.
Biochem. Pharmac.
(1986)
Cited by (1481)
Characterization of the antioxidant activity, identified free radical-relieving components by LC/QTOF/MS and acute oral toxicity studies of Tri-Tharn-Thip tea
2024, Journal of Agriculture and Food ResearchThis study assessed the antioxidant activities and bioactive maker of Tri-Than-Thip tea (Tri-TTa) to provide database support for the use of Tri-Than Thip remedy according to the Thai Pharmaceutical Textbook and aims to develop herbal medicine or food from natural products. Tri-TTa and herbal components were tested for antioxidant scavenging activity (DPPH assay, ABTS assay), chain-breaking/iron ion chelating activity (Metal Chelating Activity; MAC, the ferric-reducing antioxidant power activity; FRAP), superoxide anion radical scavenging activity (NBT assay), oxygen radical antioxidant capacity (ORAC assay), total content of Phenolic (TCP) and flavonoid (TCP) substance. The chemical components were separated and investigated by LC/QTOF/MS for safe dosages due to acute oral toxicity in rats. The Tri-TTa showed the strongest inhibition of antioxidant activity with the DPPH, ABTS, and MCA assay, with IC50 values of 0.087 ± 0.003, 0.025 ± 0.000, and 0.012 ± 0.000 mg/mL, respectively. In addition, Tri-TTa can also inhibit superoxide anion radicals, with IC50 values of 158 ± 0.009 mg/mL, and the oxygen radical was 3.47 ± 0.03 μM of TE/g extract. TCP, TCF, and FRAP values of Tri-TTa were 154.123 ± 1.326, 80.233 ± 14.268 mg equivalent/g of extract, and 1092.457 ± 106.024 mM FeSO4/mg, respectively. Additionally, Tri-TTa contains important substances in the phenolic and flavonoid groups that have good antioxidant abilities and were confirmed to be safe through acute oral toxicity testing in rats, which revealed no toxicity-related effects at high doses. Tri-TTa is a strong candidate for use as a natural product with antioxidant activity, suggesting that plant polyphenol content may promote antioxidant activity. These results support further research on Thai folk remedy infusions as promising antioxidant agents that can be developed for food, tea, or tonic drugs from natural.
Quality properties and nutritional compounds of fresh-cut pumpkin treated with supercritical carbon dioxide
2024, Journal of Supercritical FluidsThe work aimed to explore the effect of supercritical carbon dioxide (SCCD) treatment on the enzyme activity, color, carotenoid, sugar and phenolic profile, and antioxidant activity of fresh-cut pumpkins. The polyphenol oxidase (PPO) and peroxidase (POD) activities of SCCD-treated pumpkin cubes were reduced by 21% and 18%, respectively. The lightness value of SCCD-treated samples declined compared to the untreated samples, whereas the redness and yellowness values in treated samples were enhanced. The lutein, α-carotene, β-carotene and total carotenoids, glucose, sorbitol, and other polysaccharides in the SCCD-treated samples showed a fluctuation trend. Similarly, the treated sample's total phenolic contents (TPC), ABTS (2,2′- azino-bis(3-ethylbenzothiazoline-6-sulfonic acid, DPPH (2,2-diphenyl-1-picrylhydrazyl), and superoxide radical scavenging activities were increased and then reduced. An enhancement was noted in the coumaryloquinic acid I and II, caffeic acid glucoside, 4-hydroxybenzoic acid, and p-coumaric acid of SCCD-treated samples. The work demonstrated that the SCCD technique at moderate conditions could obtain higher retention of nutritional composition in fresh-cut pumpkins.
The effects of myricitrin and chebulinic acid on the rat hippocampus exposed to gamma radiation: A stereological, histochemical and biochemical study
2023, Journal of Chemical NeuroanatomyGamma radiation, a form of ionizing radiation, is used in many different areas, especially in the health field and in the treatment of cancer. However, gamma radiation used for therapeutic purposes also has numerous harmful effects on human health. This study was planned to investigate the impacts of exposure to gamma radiation on the hippocampal area and the preventive effects of myricitrin and chebulinic acid against that damage.
Thirty-six male Wistar albino rats were randomly divided into six groups. The control group was exposed to no treatment. The chebulinic acid and myricitrin groups were injected with the relevant drug at a dosage of 0.033 mg/kg) (vehicle; normal saline) per day. The gamma groups were placed in a plexiglass test setup with their heads positioned close to the source. The subjects were exposed to radiation with a mixed source containing radioactive Cs-137 and Co-60 isotopes obtained from Ondokuz Mayıs University Physics Department Nuclear Physics Laboratory for 1 h. Gamma radiation was applied 16 mGy for one hour per day for 10 days. The gamma radiation+chebulinic acid and the gamma radiation myricitrin groups also received 0.033 mg/kg per day of these drugs via injection. Immediately after the experimental procedure, all animals were subjected to behavioural tests, and perfused brain tissues were analyzed using stereological methods.
Stereological analysis showed that gamma radiation caused a decrease in the numbers of neurons in the hippocampal area (p < 0.01; One-way ANOVA) and that chebulinic acid and myricitrin reduced this decrease (p < 0.01; One-way ANOVA). Decreases in learning and memory capacity were detected in behavioural tests in rats from the Gamma group.
The study findings showed that that the adverse health effects of Gamma radiation can be ameliorated using myricitrin and chebulinic acid. Myricitrin was more effective in terms of cell proliferation and defence against oxidative stress than chebulinic acid, and exhibited a more neuroprotective effect. However, more detailed analyses should be performed before using either antioxidant for therapeutic purposes.
Bioassays and proteomics as early detection tools in postharvest management of table grapes (Vitis vinifera L.) diseases – A Review
2023, Food BiosciencePostharvest diseases are a major concern to the table grapes (Vitis vinifera L.) industry, leading to huge economic losses worldwide. Monitoring postharvest disease and early detection of fruit pathogens are crucial to mitigate disease infestation and facilitate effective management practices. Over the years, traditional visual scouting for symptoms combined with biochemical assays, serological tests and/or DNA-based approach have been useful tools in fruit disease diagnosis. However, these tools have drawbacks in accurately detecting diseases during asymptomatic stage. Hence, these methods are not the most effective for disease confirmation and pathogen identification. In contrast, proteomics could provided instantaneous results that can be used to identify asymptomatic disease stages on table grapes. Therefore, this review provides an overview on the postharvest disease causing pathogens and associated symptoms on table grapes. Prospects of using changes in biochemical assays and proteomics as early response signal in postharvest disease management were discussed. This article proposed the need for continued advancement in the development of conventional tools, with emphasized on combining these tools with more robust and responsive novel approaches for better early disease diagnostic strategies.
Study on extraction optimization, structure features, and bioactivities of an Oudemansiella raphanipies polysaccharide
2023, Process BiochemistryAn Oudemansiella raphanipies polysaccharide (ORP) was obtained to study its extraction optimization, physicochemical and structural properties, and bioactivities. Under obtained optimum conditions (liquid: solid = 40 mL/g, extraction time = 180 min, extraction temperature = 42 °C), total sugars were extracted, and then ORP was purified with a yield of 21.33 %. The molecular weight of ORP was 409 kDa, and its repeating unit was →6)-α-D-Manp-(1→4)-β-D-Xylp-(1→6)-α-D-Galp-(1→[6)-β-D-Glup-(1]4→. ORP displayed cellular and schistose surface morphology, and its microscopic structure showed sturdy cable-shaped conformations without branches. The bioactivities of ORP were estimated in terms of antioxidant and anti-inflammatory effects. The mRNA expressions of tumor necrosis factor α (TNF-α), interleukin (IL-1β), cyclooxygenase (COX-2), and inducible nitric oxide synthase (iNOS) could be significantly down-regulated to 26.93 %, 69.10 %, 24.07 %, and 46.50 % by 75 μg/mL ORP (P < 0.0001), respectively. ORP also showed strong scavenging abilities for hydroxyl (EC50 = 49.47 μg/mL), 2,2-Azino-bis-(3-ethyl-benzothiazoline-6-sulfonic acid (ABTS, EC50 = 106.52 μg/mL), and 1,1-Diphenyl-2-picrylhydrazyl (DPPH, EC50 = 1250.75 μg/mL) radicals. ORP with sturdy cable-shaped conformations exhibited excellent bioactivities, which will further facilitate the application of O. raphanipies in food and pharmaceutical fields.
Hepatoprotective Effects of Flavonoids against Benzo[a]Pyrene-Induced Oxidative Liver Damage along Its Metabolic Pathways
2024, Antioxidants