Chemistry of Non-Enzymic Browning. XI. The Reactions of Bisulphite with Reducing Sugars

1960 ◽  
Vol 13 (3) ◽  
pp. 404 ◽  
Author(s):  
DL Ingles
Keyword(s):  
Ascorbic Acid ◽  
Sulphur Dioxide ◽  
Reducing Sugars ◽  
Complex Mixture ◽  
Dehydroascorbic Acid ◽  
Keto Acids ◽  
Enzymic Browning

The reactions of reducing sugars with bisulphite have been studied at 100 �C and lower temperatures. Reducing sugars promoted the autoxidation of bisulphite to sulphur and sulphate, the ketoses being more effective than the aldoses. During the autoxidation the aldoses were oxidized, in part, to the corresponding aldonic acids. The ketose sugars reacted more rapidly and extensively than the aldoses, only 32 per cent. of unchanged fructose being recovered after 8 hr at 100 �C. Oxidation of the ketoses probably occurred via the osone and gave a complex mixture of keto acids. Ascorbic acid was converted to dehydroascorbic acid and an unidentified acid. The reactions offer possible explanations for the formation of sulphate and the loss of bisulphite observed during storage of foods treated with sulphur dioxide. An oxidative mechanism has been suggested for the inhibition of non-enzymic browning by sulphur dioxide.

Some effects of gamma radiation on several varieties of Tasmanian potatoes. 2. Biochemical changes

1965 ◽  
Vol 5 (18) ◽  
pp. 289 ◽  
Author(s):  
PA Wills
Keyword(s):  
Ascorbic Acid ◽  
Gamma Radiation ◽  
Dry Matter ◽  
Reducing Sugars ◽  
Starch Content ◽  
Sugar Content ◽  
Dehydroascorbic Acid ◽  
Ascorbic Acid Content ◽  
Reducing Sugar ◽  
Total Sugars

Tasmanian Up-to-date, Kennebec, Sebago, and Sequoia tubers were treated with low doses of gamma radiation to inhibit sprouting and were subsequently stored at 68�F or 45�F. Tubers were examined at bi-monthly intervals for some, or all, of the following biochemical constituents : dry matter, thiamin, reduced ascorbic acid, dehydroascorbic acid, total ascorbic acid, soluble reducing sugars, sucrose, total sugars, and starch. Radiation, independent of dose level, led to lower dry matter contents in the Up-to-date, Kennebec, and Sequoia tubers after four months storage, and in the Sebago tubers after six months storage at 68�F, but not at 45�F, when compared to the controls. The thiamin content of Up-to-date tubers w-as not influenced by radiation (16,000 rads). Storage w-as a more important factor than radiation in altering the ascorbic acid content of tubers. Radiation maintained, or even increased the normal level. Radiation increased the soluble reducing sugar content of Sequoia tubers, the total sugar of Sequoia and Sebago tubers, and the sucrose content of the Sebago tubers, but had little effect on the starch content of these varieties. Storage influenced some of these constituents, particularly in the Sebago variety.

scholarly journals Concentration-Dependent Antioxidant/Pro-Oxidant Activity of Ascorbic Acid in Chickens

2012 ◽  
Vol 66 (6) ◽  
pp. 256-260
Author(s):  
Nadežda Berzina ◽  
Jurijs Markovs ◽  
Mirdza Apsīte ◽  
Svetlana Vasiļjeva ◽  
Galina Smirnova ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Ascorbic Acid ◽  
Cadmium Concentration ◽  
Dehydroascorbic Acid ◽  
Cadmium Accumulation ◽  
Suppressive Effect ◽  
High Dose ◽  
Dependent Manner ◽  
Treatment Groups ◽  
Liver And Kidney

The effects of ascorbic acid supplementation on biomarkers of oxidative stress, cadmium accumulation in organs, immune system activity and kidney function in chickens were investigated. The treatment groups of chickens were fed either plain diet or diet supplemented with ascorbic acid at 100, 500, 1000 and 2000 mg/kg for four weeks. Liver and kidney tissues were assayed for cadmium concentration, and the hepatic levels of ascorbic acid and dehydroascorbic acid (DHAA; the oxidised form), malondialdehyde, glutathione, activity of glutathione peroxidase, blood serum uric acid, creatinine, lysozyme and circulating immune complexes were measured. Supplementation with a high dose of ascorbic acid (1000 and 2000 mg/kg in the diet) caused an imbalance between pro-oxidative and antioxidative activities, and induced a suppressive effect on innate immunity. The results suggest that oxidative stress compromises renal function. We observed that ascorbic acid increased cadmium accumulation in a dose-dependent manner.

scholarly journals [11C]Ascorbic and [11C]dehydroascorbic acid, an endogenous redox pair for sensing reactive oxygen species using positron emission tomography

2016 ◽  
Vol 52 (27) ◽  
pp. 4888-4890 ◽  
Author(s):  
V. N. Carroll ◽  
C. Truillet ◽  
B. Shen ◽  
R. R. Flavell ◽  
X. Shao ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Positron Emission Tomography ◽  
Ascorbic Acid ◽  
Reactive Oxygen ◽  
Dehydroascorbic Acid ◽  
Emission Tomography ◽  
Oxygen Species ◽  
Redox Pair ◽  
Positron Emission

We report the radiosynthesis of an endogenous redox pair, [11C]ascorbic acid and [11C]dehydroascorbic acid and their application to ROS sensing.

Ascorbic Acid, Dehydroascorbic Acid, and Diketogulonic Acid in Fresh and Processed Foods

1949 ◽  
Vol 21 (6) ◽  
pp. 707-709 ◽  
Author(s):  
M. B. Mills ◽  
C. M. Damron ◽  
J. H. Roe
Keyword(s):  
Ascorbic Acid ◽  
Dehydroascorbic Acid ◽  
Processed Foods
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