Effect of Cysteine on the Antioxidant Activity of Nitroxyl Radicals during the Oxidation of Methyl Linoleate in Micelles

Abstract A number of nitrones containing a partially hindered phenolic group are shown to be effective antidegradants for sulfur vulcanized rubbers. They exhibit a high level of antiozonant and antifatigue activity, but unlike commercial antiozonants they do not cause discoloration of light colored formulations. The new antidegradants are less effective than conventional additives as thermal antioxidants, but their performance as antifatigue agents and antioxidants is augmented by their use in combination with nonstaining antioxidants. The mechanism of action of the phenolic nitrones is believed to involve their oxidation to stable phenoxyl/nitroxyl radicals.

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5-Aryl-2-(3,5-dialkyl-4-hydroxyphenyl)-4,4-dimethyl-4H-imidazole 3-Oxides and Their Redox Species: How Antioxidant Activity of 1-Hydroxy-2,5-dihydro-1H-imidazoles Correlates with the Stability of Hybrid Phenoxyl–Nitroxides

Molecules ◽

10.3390/molecules25143118 ◽

2020 ◽

Vol 25 (14) ◽

pp. 3118

Author(s):

Svetlana A. Amitina ◽

Elena V. Zaytseva ◽

Natalya A. Dmitrieva ◽

Alyona V. Lomanovich ◽

Natalya V. Kandalintseva ◽

...

Keyword(s):

Antioxidant Activity ◽

Alkyl Substituent ◽

Nitroxyl Radicals ◽

The Other ◽

Redox Species ◽

Phenol Group ◽

Sterically Hindered Phenol ◽

Hindered Phenol ◽

The Stability ◽

Opposite Tendency

Cyclic nitrones of the imidazole series, containing a sterically hindered phenol group, are promising objects for studying antioxidant activity; on the other hand, they can form persistent hybrid phenoxyl–nitroxyl radicals (HPNs) upon oxidation. Here, a series of 5-aryl-4,4-dimethyl-4H-imidazole 3-oxides was obtained by condensation of aromatic 2-hydroxylaminoketones with 4-formyl-2,6-dialkylphenols followed by oxidation of the initially formed N-hydroxy derivatives. It was shown that the antioxidant activity of both 1-hydroxy-2,5-dihydroimidazoles and 4H-imidazole 3-oxides increases with a decrease in steric volume of the alkyl substituent in the phenol group, while the stability of the corresponding HPNs generated from 4H-imidazole 3-oxides reveals the opposite tendency.

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Effect of superoxide dismutase on the oxidation of methyl linoleate in micelles inhibited by nitroxyl radicals

Russian Chemical Bulletin ◽

10.1007/s11172-016-1690-7 ◽

2016 ◽

Vol 65 (12) ◽

pp. 2985-2987 ◽

Cited By ~ 3

Author(s):

I. V. Tikhonov ◽

E. M. Pliss ◽

L. I. Borodin ◽

V. D. Sen’

Keyword(s):

Superoxide Dismutase ◽

Methyl Linoleate ◽

Nitroxyl Radicals

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Antioxidant activity of casein and Maillard reaction products from casein-sugar mixtures

Journal of Dairy Research ◽

10.1017/s0022029900029885 ◽

1991 ◽

Vol 58 (3) ◽

pp. 313-320 ◽

Cited By ~ 43

Author(s):

Barry J. McGookin ◽

Mary-Ann Augustin

Keyword(s):

Antioxidant Activity ◽

Methyl Linoleate ◽

Maillard Reaction ◽

Model System ◽

Sugar Concentration ◽

Maillard Reaction Products ◽

Reaction Products ◽

Sugar Mixtures

SummaryThe antioxidant activity of casein and Maillard reaction products obtained by reaction of casein with glucose or lactose was studied. Antioxidant activity was evaluated in a model System containing methyl linoleate with haemoglobin as a pro-oxidant. Casein was antioxidative and heating casein in the presence of glucose or lactose resulted in enhancement of antioxidant activity. The development of antioxidant activity in reacted casein–sugar mixtures was determined as a function of initial casein and sugar concentration. The observed antioxidant activity of reacted casein–sugar mixtures was due to casein itself and Maillard reaction products resulting from reacting casein with sugar.

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Antioxidant activity of flavonol aglycones and their glycosides in methyl linoleate

Journal of the American Oil Chemists Society ◽

10.1007/s11746-999-0060-0 ◽

1999 ◽

Vol 76 (1) ◽

pp. 139-144 ◽

Cited By ~ 80

Author(s):

Anu Hopia ◽

Marina Heinonen

Keyword(s):

Antioxidant Activity ◽

Methyl Linoleate

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Antioxidant activity of 1,4-dihydropyridine derivatives in β-carotene-methyl linoleate, sunflower oil and emulsions

Food Chemistry ◽

10.1016/s0308-8146(98)00265-9 ◽

1999 ◽

Vol 66 (2) ◽

pp. 189-195 ◽

Cited By ~ 19

Author(s):

A Abdalla

Keyword(s):

Antioxidant Activity ◽

Methyl Linoleate ◽

Sunflower Oil ◽

Dihydropyridine Derivatives ◽

Β Carotene

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Chemical Composition and Antioxidant Activity of Juices from Mature and Immature Acerola (Malpighia emarginata DC)

Food Science and Technology International ◽

10.1177/1082013205056785 ◽

2005 ◽

Vol 11 (4) ◽

pp. 315-321 ◽

Cited By ~ 22

Author(s):

A. M. Righetto ◽

F. M. Netto ◽

F. Carraro

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Chemical Composition ◽

Phenolic Compounds ◽

Methyl Linoleate ◽

Vitamin C ◽

Hplc Analysis ◽

Syringic Acid ◽

Coumaric Acid ◽

Malpighia Emarginata

Chemical composition and antioxidant activity of juice from immature and mature acerola and of concentrated juice from immature acerola were determined. Tartaric, malic and citric acids and a high content of ascorbic acid were found in all the juices. Vitamin C contents were 4.80, 1.90 and 0.97 g/100 g for the concentrated immature, the immature, and the mature acerola juices respectively. The total phenol contents decreased during ripening, from 3.8 mg of catechin/g for immature acerola juice to 1.4 mg of catechin/g for mature acerola juice. The concentrated immature juice had a content of 9.2mg of catechin/g of juice. Catechin, gallic acid, coumaric acid, syringic acid, caffeic acid and ferrulic acid were detected in immature acerola juice by HPLC analysis whereas mature acerola juice showed only one predominant peak with a retention time similar to that of ferrulic acid. The concentrated juice from immature acerola reduced the oxidation of methyl linoleate by 57.2% while the juice from immature acerola reduced the oxidation by 28.1%. These results stated that the antioxidant potential of the acerola juice depended on its content of phenolic compounds and the vitamin C.

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