Formation of Singlet Oxygen-Like Active Oxygen Species in System Containing Nickel(II) Complex and Aliphatic Aldehyde

1992 ◽  
Vol 21 (7) ◽  
pp. 1291-1294 ◽  
Author(s):  
Yuzo Nishida ◽  
Tetsuya Fujimoto ◽  
Noriko Tanaka
Keyword(s):  
Singlet Oxygen ◽  
Active Oxygen Species ◽  
Aliphatic Aldehyde ◽  
Active Oxygen ◽  
Oxygen Species

Active oxygen species in the liver of rats submitted to chronic hypobaric hypoxia

1993 ◽  
Vol 264 (6) ◽  
pp. C1395-C1400 ◽  
Author(s):  
L. E. Costa ◽  
S. Llesuy ◽  
A. Boveris
Keyword(s):  
Steady State ◽  
Singlet Oxygen ◽  
Active Oxygen Species ◽  
Liver Mitochondria ◽  
Active Oxygen ◽  
Female Rats ◽  
H2o2 Production ◽  
Oxygen Species ◽  
State Concentration

The spontaneous in situ liver chemiluminescence of female rats submitted to 4,400 m (simulated altitude) for 2 mo and of their corresponding controls at sea level was determined as an approach to the measurement of the intracellular steady-state concentrations of singlet oxygen and oxygen free radicals. Spontaneous liver chemiluminescence was decreased by approximately 40% in hypoxic rats, whereas CCl4-induced chemiluminescence was unchanged. Liver mitochondria isolated from hypoxic rats showed a 53% decreased rate of H2O2 production and an increased content of cytochrome b (36%), with normal content of cytochromes c1, c, and a-a3. Superoxide dismutase showed a 26% decrease in activity, whereas catalase and glutathione peroxidase activities were not significantly decreased by this extent of hypoxia. Cytochrome P-450 and glutathione contents were unchanged. There were no significant differences in the hydroperoxide-initiated chemiluminescence (an estimation of tissue chain-breaker antioxidants) of homogenates, mitochondria, and microsomes. Results suggest that in chronic hypoxia there is a lower rate of generation of active oxygen species in liver, leading to a decreased steady-state concentration of singlet oxygen.

scholarly journals 367 Scavenging Capacity of Active Oxygen Species in Blackberry

HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 455E-455
Author(s):  
Shiow Y. Wang ◽  
Hongjun Jiao
Keyword(s):  
Hydrogen Peroxide ◽  
Ascorbic Acid ◽  
Singlet Oxygen ◽  
Hydroxyl Radicals ◽  
Fruit Juice ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Scavenging Capacity ◽  
Β Carotene

The effect of blackberries (Rubus sp.) genotypes on antioxidant activities against superoxide radicals (O2–), hydrogen peroxide (H2O2), hydroxyl radicals (OH), and singlet oxygen (O,), was evaluated. The results were expressed as percent inhibition of active oxygen species production in the presence of fruit juice. The active oxygen radical absorbance capacity (ORAC) value referred to the net protection in the presence of fruit juice, and was expressed as micromoles of α-tocopherol, ascorbate, α-tocopherol, and β-carotene equivalents per 10 g of fresh weight for O2–, H2O2, OH, and O2, respectively. Among the different cultivars, juice of Hull' blackberry had the highest oxygen species, superoxide radicals (O2–), hydrogen peroxide (H2O2), hydroxyl radicals (OH), and singlet oxygen (O2,) scavenging capacity. Different antioxidants have their functional scavenging capacity against active oxygen species. There were interesting and marked differences among the different antioxidants in their abilities to inhibit the different active oxygen species. β-carotene had by far the highest scavenging activity against O2– but had absolutely no effect on H2O2. Ascorbic acid was the best at inhibiting H2O2 free radical activity. For OH, there was a wide range of scavenging capacities with α-tocopherol the highest and ascorbic acid the lowest. Glutathione had higher O2– scavenging capacity compared to the other antioxidants.

Hydrogen peroxide is the most toxic oxygen species for Onchocerca cervicalis microfilariae

Parasitology ◽  
1990 ◽  
Vol 100 (3) ◽  
pp. 407-415 ◽  
Author(s):  
H. L. Callahan ◽  
R. K. Chouch ◽  
E. R. James
Keyword(s):  
Hydrogen Peroxide ◽  
Hydroxyl Radical ◽  
Singlet Oxygen ◽  
Superoxide Radical ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Low Levels ◽  
Scavenging Enzymes

SUMMARYThe toxicity of the active oxygen species hydrogen peroxide, superoxide radical, hydroxyl radical and singlet oxygen to microfilariae (mf) has been studied in vitro, using active oxygen-generating systems and scavengers/inhibitors. Mf viability was monitored by uptake of the radiolabel, [3H]2-deoxy-D-glouse. Hydrogen peroxide and singlet oxygen, but not superoxide radical or hydroxyl radical, are toxic for mf. Hydrogen peroxide was toxic for mf within 2 h at concentrations as low as 5 ¼, an amount eosinophils have been shown to release in vitro (Weiss et al. 1986). Catalase and thiourea, but not inactivated catalase, superoxide dismutase (SOD), singlet oxygen scavengers, or hydroxyl radical scavengers, protected mf. Mf have relatively high levels of endogenous SOD but no measurable glutathione peroxidase and low levels of catalase when compared with other parasites (Callahan, Crouch & James, 1988). The low levels of hydrogen peroxide-scavenging enzymes correlate well with mf sensitivity to hydrogen peroxide and the protective effect of exogenous catalase.

scholarly journals Induction of benzo[a]pyrene Mono-oxygenase in liver cell culture by the photochemical generation of active oxygen species. Evidence for the involvement of singlet oxygen and the formation of a stable inducing intermediate

1976 ◽  
Vol 158 (1) ◽  
pp. 109-117 ◽  
Author(s):  
A J Paine
Keyword(s):  
Singlet Oxygen ◽  
Culture Medium ◽  
Enzyme System ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Photochemical Generation ◽  
Single Oxygen ◽  
Cytochrome P 450 ◽  
Stimulation Of

1. The photochemical generation of excited states of oxygen in liver cell culture by the mild ilumination of culture medium containing riboflavin, results in stimulation of benzo[a]pyrene 3-mono-oxygenase, a cytochrome P-450-linked mono-oxygenase. 2. The same large increase in mono-oxygenase activity was found when medium containing riboflavin was illuminated in the absence of cells and then stored in the dark for 24h before contact with the cells. From this it may be inferred that stimulation is due to the formation of a stable inducer in the culture medium. Further experiments indicate that the stable inducer is due to the photo-oxidation of an amino acid. 3. Evidence that singlet oxygen is responsible for initiating the stimulation of the mono-oxygenase is based on the use of molecules that scavenge particular active oxygen species. Of all the scavengers tested, only those that scavenge single oxygen inhibited the stimulation. 4. A hypothesis is developed to relate the stimulation of the mono-oxygenase by singlet oxygen in cultured cells to the regulation of the cytochrome P-450 enzyme system in vivo. It is suggested that single oxygen generation within cells may be a common factor linking the many structurally diverse inducers of the enzyme system.

Characterization and functional properties of new everbearing strawberry (Fragaria x ananasa Duch.) cultivar, ‘Summertiara’ berries

2014 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
Takeshi Nagai ◽  
Misuzu Tamai ◽  
Masato Sato ◽  
Yasuhiro Tanoue ◽  
Norihisa Kai ◽  
...  
Keyword(s):  
Vitamin C ◽  
Sensory Evaluation ◽  
Functional Properties ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Antihypertensive Activity ◽  
Oxygen Species ◽  
Total Anthocyanins ◽  
Strawberry Cultivar ◽  
The Stability

Background: In recent years, a new everbearing strawberry cultivar, ‘Summertiara’ was cultivated to supply the strawberries in pre-harvest season from July to October in Japan. For highly research and development of processing of this cultivar, ‘Summertiara’ berries, the objective of this study was to characterize these berries, with relation to chemical parameters, total phenols, total flavonoids, total vitamin C, and total anthocyanins, and was to investigate the solubility and the stability of anthocyanins from the berries. Moreover, the functional properties such as antioxidative activity, active oxygen species scavenging activity, and antihypertensive activity were also evaluated.Methods: Chemical analysis, colour measurement, and sensory evaluation of new everbearing strawberry cultivar, ‘Summertiara’ berries were performed. Next, the solubility of anthocyanins from the berries and stability of these against pH, temperature, and an incandescent lighting were investigated. Moreover, functional properties of the extracts prepared from berries were elucidated using 5 different methods.Results: The contents of water, proteins, lipids, carbohydrates, and ash were the same as those of other cultivar berries. The sugar-acid ratio in the berries was low; these were acidulous. By sensory evaluation, the main factors were vivid red colour, aroma, and acidity. The berries were rich in phenols, flavonoids, vitamin C, and anthocyanins. The anthocyanins of the berries became unstable by heat treatment and light exposures such as visible rays. On the other hand, the extracts prepared from the berries showed the functionalities such as antioxidant activity, active oxygen species scavenging activities, and antihypertensive activity.  Conclusions: The strawberry cultivar, ‘Summertiara’ berries were the most suitable for processing ingredient of strawberry-derived products with superior health promoting functionalities.Keywords: Summertiara, everbearing strawberry cultivar, characterization, sensory evaluation, color and storage, functional property

Identifying the Active Oxygen Species in SnO2 Based Gas Sensing Materials: An Operando IR Spectrsocopy Study

2015 ◽  
Vol 119 (21) ◽  
pp. 11792-11799 ◽  
Author(s):  
David Degler ◽  
Susanne Wicker ◽  
Udo Weimar ◽  
Nicolae Barsan
Keyword(s):  
Gas Sensing ◽  
Active Oxygen Species ◽  
Active Oxygen ◽  
Oxygen Species ◽  
Ir Spectrsocopy
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