Hydroxyl-radical scavenging activity of hydrogen does not significantly contribute to its biological function

AbstractSince Ohsawa et al. reported a biological antioxidant function of hydrogen in 2007, researchers have now shown it to exert protective effects in a wide range of human and animal disease models. Clinical observations and scientific arguments suggest that a selective scavenging property of H2 cannot adequately explain the beneficial effects of hydrogen. However, there is no experiment challenging the original published data, which suggested that molecular hydrogen dissolved in solution reacts with hydroxyl radicals in cell-free systems. Here we report that a hydrogen-saturated solution (0.6 mM) did not significantly reduce hydroxyl radicals in the Fenton system using 1 mM H2O2. We replicated the same condition as Ohsawa’s study (i.e. 5 μM H2O2), and observed a decrease in •OH radicals in both the H2-rich and N2-rich solutions, which may be caused by a decreased dissolved oxygen concentration. Finally, we determined the effect of hydrogen on a high-valence iron enzyme, horseradish peroxidase (HRP), and found that hydrogen could directly increase HRP activity in a dose-dependent manner. Overall, these results indicate that although H2 and •OH can react, the reaction rate is too low to have physiological function. The target of hydrogen is more complex, and its interaction with enzymes or other macro-molecules deserve more attention and in-depth study.

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Enzymatic Extraction of Polysaccharides from Laminaria Japonica and their Free Radical Scavenging Activity and Antimicrobial Activity Evaluation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.605 ◽

2012 ◽

Vol 479-481 ◽

pp. 605-610 ◽

Cited By ~ 2

Author(s):

Jing Chen ◽

Miao Ping Tian ◽

Shang Gui Deng ◽

Xu Bo Fang

Keyword(s):

Hydroxyl Radicals ◽

Ph Value ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Laminaria Japonica ◽

Dependent Manner ◽

Scavenging Activity ◽

Enzymatic Extraction ◽

Concentration Dependent Manner ◽

Potential Applications

Complex enzymes, including cellulase, pectinase and neutral protease were used for extraction of laminaria polysaccharides, which have a broad range of applications in the food, pharmaceutical, agricultural and chemical industries. The enzymatic extraction conditions were optimized and the maximum polysaccharides yield was achieved with the addition of 2.5% of enzymes under a pH value of 5.0 and temperature of 55 °C for 210 min. Polysaccharides prepared under the above conditions were effective against some pathogenic and spoilage microorganisms, including Salmonella sp, Bacillus subtilis, Enterococcus faecalis, Proteus vulgaris, Staphylococcus aureus, Escherichia coli, Pseudomonas fluorescens, with a diameter range of 5.1 ± 0.29-12.5 ± 0.78 mm. In addition, antioxidant activity of laminaria polysaccharides against hydroxyl radicals was also investigated and it was observed that the polysaccharides displayed obvious scavenging activity on hydroxyl radicals in concentration-dependent manner. Overall, polysaccharides from Laminaria Japonica demonstrated potential applications in food safety and control.

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Protective Effect of Dealcoholized Persimmonwine on H2O2 - Induced Oxidative Injury in H9c2 Cardiomyocytes

Journal of Food Research ◽

10.5539/jfr.v2n4p61 ◽

2013 ◽

Vol 2 (4) ◽

pp. 61

Author(s):

Jin Taek Hwang ◽

Chan Kyu Han ◽

Sang Yoon Choi ◽

Sung Soo Kim

Keyword(s):

Oxidative Stress ◽

Gallic Acid ◽

High Performance ◽

Cell Injury ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Dependent Manner ◽

Protective Effects ◽

H9c2 Cardiomyocytes ◽

Dose Dependent

In this study, we investigated the antioxidant capacity of persimmon wine (PW) and dealcoholized persimmon wine (DPW). Both PW and DPW showed radical scavenging activity in the DPPH (1-diphenyl-2-picrylhydrazyl) assay. We next analyzed the phenolic content and major compounds present in PW using high-performance liquid chromatography (HPLC). Phenolic compounds, including gallic acid, catechin, and epicatechin, were found in PW. Gallic acid was the most abundant phenolic compound (157.5 µg/ml) in PW. In addition, the protective effects of DPW and gallic acid against H2O2-induced cell injury in H9c2 cardiomyocytes were investigated. Pretreatment with DPW or gallic acid strongly inhibited H2O2-induced cell death in a dose-dependent manner. These results suggested that PW and its major phenolic component, gallic acid, were effective inhibitors of oxidative stress and oxidative stress-induced cardiomyocyte injury.

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Evaluation of antioxidant enzyme content, phenolic content, and antibacterial activity of Commiphora gileadensis grown in Saudi Arabia

Main Group Chemistry ◽

10.3233/mgc-200969 ◽

2021 ◽

Vol 19 (4) ◽

pp. 329-343

Author(s):

Yaaser Q. Almulaiky ◽

Ammar AL-Farga

Keyword(s):

Antibacterial Activity ◽

Saudi Arabia ◽

Oral Hygiene ◽

Leaf Extract ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Scavenging Activity ◽

Reference Drug ◽

Wide Range ◽

Peel Extract

Commiphora gileadensis is commonly used in Saudi Arabia for oral hygiene. A lack of data about its biological activity encouraged us to evaluate the antioxidant and antibacterial activities of its leaf and stem extracts. Ethanol, methanol, acetone and deionized water were tested as extraction solvents. 80% methanol gave the highest extracted concentrations of phenolic and flavonoid substances. The leaf and stem extracts were respectively evaluated for their radical scavenging activity with DPPH (EC50 = 3.39, and 1.06), ABTS (EC50 = 0.690, and 0.55), and peroxide scavenging activity (EC50 = 2.43, and 1.28). GC-MS identified a wide range of compounds that may be responsible for these activities of the results observed. The highest levels of chlorophyll, carotenoids, and lycopene were found in the leaf extract while level of proanthocyanidins was found in the stem peels extract. The peroxidase and catalase activities of stem peel extract were higher than those of the leaf extract. The findings showed that the leaf and stem peel extracts of C. gileadensis exhibited significant antibacterial activity against the test organisms. The minimum inhibitory concentrations for the plant extracts were compared with the standard reference drug Augmentin but the time–kill curves for the C. gileadensis extracts showed that they were less effective than Augmentin. Moreover, the stem peel extract exhibited stronger antibacterial activity than the leaf extract. In conclusion, C. gileadensis can be an important source of natural antioxidants, used as a healthy chewing stick for teeth brushing and oral hygiene purposes.

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Comparison of Phenolic Contents and Scavenging Activities of Miang Extracts Derived from Filamentous and Non-Filamentous Fungi-Based Fermentation Processes

Antioxidants ◽

10.3390/antiox10071144 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1144

Author(s):

Aliyu Dantani Abdullahi ◽

Pratthana Kodchasee ◽

Kridsada Unban ◽

Thanawat Pattananandecha ◽

Chalermpong Saenjum ◽

...

Keyword(s):

Filamentous Fungi ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Protective Effects ◽

Tea Leaves ◽

Antioxidant Power ◽

Phenolic Contents ◽

Ic50 Values ◽

Ferric Reducing Antioxidant Power ◽

The Impact

The study investigated the impact of the fermentation process on the phenolic contents and antioxidant and anti-inflammatory activities in extracts of Miang, an ethnic fermented tea product of northern Thailand. The acetone (80%) extraction of Miang samples fermented by a non-filamentous fungi-based process (NFP) and filamentous fungi-based process (FFP) had elevated levels of total polyphenols, total tannins, and condensed tannins compared to young and mature tea leaves. The antioxidant studies also showed better the half-maximal inhibitory concentration (IC50) values for fermented leaves in both 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity assays as well as improved ferric reducing antioxidant power (FRAP) compared to young and mature tea leaves. Extracts of NFP and FFP samples at concentrations of 50 and 100 ppm showed better protective effects against hydrogen peroxide (H2O2)-induced intracellular reactive oxygen species (ROS) production in HT-29 colorectal cells without exerting cytotoxicity. Additionally, lipopolysaccharide (LPS)-induced production of nitric oxide (a proinflammatory mediator as well as a reactive nitrogen species) was also inhibited by these fermented Miang extracts with an IC50 values of 17.15 μg/mL (NFP), 20.17 μg/mL (FFP), 33.96 μg/mL (young tea leaves), and 31.33 μg/mL (mature tea leaves). Therefore, both NFP-Miang and FFP-Miang showed the potential to be targeted as natural bioactive functional ingredients with preventive properties against free radical and inflammatory-mediated diseases.

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Antimicrobial and antioxidant potentials of non-cytotoxic extracts of corticolous lichens sampled in Armenia

AMB Express ◽

10.1186/s13568-021-01271-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Razmik Sargsyan ◽

Arsen Gasparyan ◽

Gohar Tadevosyan ◽

Hovik Panosyan

Keyword(s):

Antifungal Activity ◽

Methanol Extract ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Cytotoxic Activities ◽

Bacterial Strains ◽

Evernia Prunastri ◽

Wide Range ◽

Antibacterial And Antifungal ◽

Acetone Extracts

AbstractDue to wide range of secondary metabolites, lichens were used from antiquity as sources of colorants, perfumes and medicaments. This research focuses on exploring the antioxidant, antimicrobial and cytotoxic activities of methanol, ethanol, acetone extracts and aqueous infusions of corticolous lichens sampled from Armenia. Methanol, ethanol and acetone extracts from all tested lichens were active against Gram-positive bacterial strains. The most effective solvent to retrieve antimicrobial compounds was methanol. Aqueous infusions of tested lichens didn’t show any significant antibacterial and antifungal activity. The highest antimicrobial activity was observed for methanol extract of Ramalina sinensis. The minimum inhibitory concentration of methanol extract of Ramalina sinensis were 0.9–1.8 mg mL− 1. Pseudevernia furfuracea demonstrated antifungal activity (Ø 12 mm). Methanol extract of Parmelia sulcata demonstrated largest 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity (71 %). The cytotoxicity was measured on human HeLa (cervical carcinoma) cell lines using microculture tetrazolium test assay. The IC50 values estimated for methanol extracts of Peltigera praetextata, Evernia prunastri, Ramalina sinensis and Ramalina farinacea species in HeLa cell line were within 1.8–2.8 mg mL− 1 and considered as non-cytotoxic. Obtained results suggest that studied lichens can be prospective in biotechnologies as alternative sources of antimicrobial and antioxidant substances.

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Synthesis, Antiproliferative Activity and Radical Scavenging Ability of 5-O-Acyl Derivatives of Quercetin

Molecules ◽

10.3390/molecules26061608 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1608

Author(s):

Stephen Lo ◽

Euphemia Leung ◽

Bruno Fedrizzi ◽

David Barker

Keyword(s):

Antiproliferative Activity ◽

Biological Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Breast Cancer Cell Lines ◽

Scavenging Activity ◽

Plant Materials ◽

Wide Range ◽

Derivatives Of ◽

Acyl Derivatives

Quercetin is a flavonoid that is found in many plant materials, including commonly eaten fruits and vegetables. The compound is well known for its wide range of biological activities. In this study, 5-O-acyl derivatives of quercetin were synthesised and assessed for their antiproliferative activity against the HCT116 colon cancer and MDA-MB-231 breast cancer cell lines; and their radical scavenging activity against the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical species. Four derivatives were found to have improved the antiproliferative activity compared to quercetin whilst retaining radical scavenging activity.

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Antioxidant activity of mandarin (Citrus reticulata) peel

Acta periodica technologica ◽

10.2298/apt1041195t ◽

2010 ◽

pp. 195-203 ◽

Cited By ~ 14

Author(s):

Vesna Tumbas ◽

Gordana Cetkovic ◽

Sonja Djilas ◽

Jasna Canadanovic-Brunet ◽

Jelena Vulic ◽

...

Keyword(s):

Radical Scavenging Activity ◽

Waste Product ◽

Radical Scavenging ◽

Natural Antioxidants ◽

Protective Effects ◽

Dpph Radical ◽

Esr Spin Trapping ◽

Accelerated Storage ◽

Mandarin Peel ◽

Peel Extract

Mandarin peel, a waste product coming from juice production, was extracted by conventional extraction with 70% acetone. Content of flavonoids in mandarin peel extract (MPE) was determined by HPLC. Hesperidin was the most dominant flavonoid. Free radical scavenging activity of MPE on stable DPPH radicals and reactive hydroxyl radicals was also evaluated. EC50 value determined in spectrophotometrical DPPH radical assay was 0.179 mg/ml, while this value in ESR spin trapping hydroxyl radical assay was 0.415 mg/ml. Also, MPE showed protective effects in stabilising sunflower oil during accelerated storage. The results indicated that mandarin peel can be a valuable source of natural antioxidants.

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Strong antihemolytic and antioxidant properties of aqueous extract from Algerian Hammada elegans (Bge.) Botsch (Chenopodiaceae)

Current Enzyme Inhibition ◽

10.2174/1573408017666210419115739 ◽

2021 ◽

Vol 17 ◽

Author(s):

Brahim Asseli ◽

Reguia Mahfoudi ◽

Amar Djeridane ◽

Mohamed Yousfi

Keyword(s):

Free Radical ◽

Aqueous Extract ◽

Radical Scavenging Activity ◽

Condensed Tannin ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Total Phenolic ◽

Dependent Manner ◽

Vitro Assay

Background: Research on medicinal plant antioxidants has emerged as a potential therapeutic to prevent free radical generated damage in the human body. Hammada elegans Botsch (popularly known as “Ajram”) is a xerophytic plant widely found in Laghouat region, but there are only a few reports about the biological or chemical properties of these species. Hence, the aim of this study is to investigate the antioxidant and the antihemolytic activities of hexanic, acetonic, methanolic and aqueous extracts of aerial parts of Algerian Hammada elegans Botsch by employing different in vitro assay systems. Methods: The total phenolic content, the flavonoid content and the condensed tannin amount were analyzed using Folin-Ciocalteu, aluminum chloride and vanillin assays, respectively. The in vitro antioxidant capacity of extracts was assessed by CUPRAC, iron chelating, ABTS•+and antihemolytic assays, and was expressed as EC50 values. Results: Among the analyzed extracts, the aqueous extract had the highest phenolic, flavonoid and tannin contents. Also, this extract displayed the highest antioxidant capacities compared to the other extracts and standards. Its EC50 value for ABTS radical-scavenging activity was 0.265 ± 0.003 mg/L. Moreover, this extract showed high iron (II) chelating ability (EC50 = 0.958 ± 0.001 mg/L), and good antioxidant activity in the cupric ion reducing activity (CUPRAC) in a concentration dependent manner (EC50 were 0.709 ± 0.002 mg/L). Additionally, this extract had the best antihemolytic activity against AAPH-induced hemolysis (EC50=0.090 ± 0.004 mg/L). Conclusion: Our study revealed that the aqueous extract of Hammada elegans Botsch, is a potential source of antioxidants which possess a high protective effect of membrane against free radical.

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RELATIONSHIP BETWEEN ANTIOXIDANT PROPERTIES AND NUTRITIONAL COMPOSITION OF SOME GALACTOPOIETICS HERBS USED IN INDONESIA: A COMPARATIVE STUDY

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2016v8i12.14964 ◽

2016 ◽

Vol 8 (12) ◽

pp. 236 ◽

Cited By ~ 4

Author(s):

Ade Chandra Iwansyah ◽

Rizal M. Damanik ◽

Lilik Kustiyah ◽

Muhammad Hanafi

Keyword(s):

Antioxidant Activity ◽

Chemical Composition ◽

Total Phenolics ◽

Radical Scavenging Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Nutritional Composition ◽

Total Flavonoids ◽

Wide Range ◽

Phenolics Content

Objective: The objectives of this research were to evaluate and compare the antioxidant activity; phenolics and flavonoids contents; and chemical composition of some galactopoietic herbs used in Indonesia and to find a possible relationship between antioxidant activity; phenolics, flavonoids and chemical composition of these plants.Methods: A wide range of analytical parameters was studied, including yield; pH; water activity (aw); total color difference; phenolics and flavonoids content; moisture; ash; protein; fat; carbohydrate; fiber; calcium; zinc; magnesium; potassium; iron content; and the data were analyzed by partial least squares (PLS) regression analysis and principal component analysis (PCA) to evaluate the correlation between the parameters and classification of the plants. Folin–cioceltaeu assay, aluminum chloride assay and DPPH scavenging assay were used to evaluate of total phenolics content and free radical scavenging activity of the ethanolic extract of galactopoietic herbs.Results: All of the galactagogue herbs, viz. Plectranthus amboinicus (Lour.) (PA), Sauropus androgynus (SA), Moringa oleifera (MO), and Carica papaya leaves (CP) exhibited good results of TPC, TFC and antioxidant activity. MO contained the highest average of total phenolics content (53.89 mg GAE/g). SA with a ratio of total flavonoids to total phenolics (TF/TP) which is 1.59 contained the highest average of total flavonoids and antioxidant activity (IC50), 43.63 mg QE/g and 126.13 μg/ml, respectively, followed by MO>CA>PA. Based on PLS and PCA analysis, antioxidant activity correlated with fat, protein, phenolics content, flavonoids content and pH, but only the total flavonoids content correlated strongly with antioxidant activity.Conclusion: This provides useful data about the studied relationships and chemical patterns in some galactopoietic herbs used and provides a helpful tool for understanding much more about the interpretation of results from the experiments and the mechanism of biosynthesis in plants.

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Ultrasonic Extraction of Bioactive Compounds From Green Soybean Pods and Application in Green Soybean Milk Antioxidants Fortification

10.21203/rs.3.rs-1048606/v1 ◽

2021 ◽

Author(s):

Noppol Leksawasdi ◽

Siraphat Taesuwan ◽

Trakul Prommajak ◽

Charin Techapun ◽

Rattanaporn Khonchaisri ◽

...

Keyword(s):

Antioxidant Activity ◽

Bioactive Compounds ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Bioactive Compound ◽

Natural Antioxidants ◽

Dependent Manner ◽

Ultrasound Technique ◽

Antioxidant Power ◽

Soybean Milk

Abstract Green soybean (Glycine max L.) pods (GSP) are agro-industrial waste from the production of frozen green soybean and milk. These pods contain natural antioxidants and various bioactive compounds that are still underutilized. Polyphenols and flavonoids in GSP were extracted by ultrasound techniques and used in antioxidant fortification of green soybean milk. The ultrasound extraction that yielded the highest total polyphenol content was 50% amplitude for 10 min, whereas maximum flavonoids content was obtained at 50% amplitude for 15 min. Radical scavenging activity assayed by 2,2-diphenyl-1-picryl-hydrazyl radical (DPPH) and ferric reducing antioxidant power (FRAP) methods did not differ significantly (p>0.05) between the two conditions. Response surface methodology was applied to analyze an optimum ultrasonic-assisted extraction (UAE) condition of these variables. The highest desirability was found to be 50% amplitude with extraction time of 12.5 min. Fortification of the GSP extracts (1-3% v/v) in green soybean milk resulted in higher levels of bioactive compounds and antioxidant activity in a dose-dependent manner. Procyanidins were found to be the main polyphenols in dried GSP which were present at the concentration of 104.1 ± 2.1 mg/g dry sample, respectively. Addition of GSP extracts obtained by using an ultrasound technique to green soybean milk increased its bioactive compound content especially procyanidins as well as its antioxidant activity.

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