Ascoric Acid suppliers

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Ascorbic acid is a naturally occurring organic compound with antioxidant properties. It is a white solid, but impure samples can appear yellowish. It dissolves well in water to give mildly acidic solutions. Ascorbic acid is one form ("vitamer") of vitamin C. It was originally called L-hexuronic acid, but when it was found to have vitamin C activity in animals ("vitamin C" being defined as a vitamin activity, not then a specific substance), the suggestion was made to rename L-hexuronic acid. The new name for L-hexuronic acid is derived from a- (meaning "no") and scorbutus (scurvy), the disease caused by a deficiency of vitamin C. Because it is derived from glucose, many animals are able to produce it, but humans require it as part of their nutrition. Other vertebrates lacking the ability to produce ascorbic acid include other primates, guinea pigs, teleost fishes, bats,and birds, all of which require it as a dietary micronutrient (that is, a vitamin).Ascorbic acid is easily oxidized and so is used as a reductant in photographic developer solutions (among others) and as a preservative. In fluorescence microscopy and related fluorescence - based techniques, ascorbic acid can be used as an antioxidant to increase fluorescent signal and chemically retard dye photobleaching. It is also commonly used to remove dissolved metal stains, such as iron, from fiberglass swimming pool surfaces. In plastic manufacturing, ascorbic acid can be used to assemble molecular chains more quickly and with less waste than traditional synthesis methods.Ascorbic acid is prepared industrially from glucose in a method based on the historical Reichstein process. In the first of a five-step process, glucose is catalytically hydrogenated to sorbitol, which is then oxidized by the microorganism Acetobacter suboxydans to sorbose. Only one of the six hydroxy groups is oxidized by this enzymatic reaction. From this point, two routes are available. Treatment of the product with acetone in the presence of an acid catalyst converts four of the remaining hydroxyl groups to acetals. The unprotected hydroxyl group is oxidized to the carboxylic acid by reaction with the catalytic oxidant TEMPO (regenerated by sodium hypochlorite — bleaching solution). (Historically, industrial preparation via the Reichstein process used potassium permanganate.) Acid-catalyzed hydrolysis of this product performs the dual function of removing the two acetal groups and ring-closing lactonization. This step yields ascorbic acid. Each of the five steps has a yield larger than 90 %.Ascorbic acid resembles the sugar from which it is derived, being a ring with many oxygen-containing functional groups. The molecule exists in equilibrium with two ketone tautomers, which are less stable than the enol form . In solutions, these forms of ascorbic acid rapidly interconvert.Nucleophilic attack of ascorbic enol on proton to give 1,3-diketone.Ascorbic acid is found in plants and animals where it is produced from glucose. Animals must either produce it or digest it, otherwise a lack of vitamin C may cause scurvy which may eventually lead to death. Reptiles and older orders of birds make ascorbic acid in their kidneys. Recent orders of birds and most mammals make ascorbic acid in their liver where the enzyme L-gulono lactone oxidase is required to convert glucose to ascorbic acid. Humans, some other primates, and guinea pigs are not able to make L-gulono lactone oxidase because of a genetic mutation and are therefore unable to make ascorbic acid. Synthesis and signalling properties are still under investigation.Traditionally, ascorbic acid is produced via the Reichstein process, which is a chemical synthesis route with several process steps. In the last 20 years, the development of biotechnological processes for ascorbic acid has been in focus. More information about ascorbic acid and its utilization in beverage, food, and animal nutrition as well as its biotechnological production are offered in Industrial Production of L-Ascorbic Acid (Vitamin C) and D-Isoascorbic Acid.