Starch, periodic acid oxidation

C. G. Caldwell and R. M. Hixon, A study of the periodic acid oxidation of starches and dextrins as a means of determining molecular size, J. Biol. Chem., 123 (1938) 595-606. 

Jackson EL, Hudson CS. Studies on the cleavage of the carbon chain of glycosides by oxidation. A new method for determining ring structures and alpha and beta configurations of glycosides. J Am Chem Soc 1937 59 994-1003. Jackson EL, Hudson CS. The structure of the products of the periodic acid oxidation of starch and cellulose. J Am Chem Soc 1938 60 989-991. 

Oxidation of Starch.97- 98- 114 Oxidation in Aqueous -Suspension. Ten grams of cornstarch or potato starch, previously dried at 100° for about twenty hours, is suspended in 290 cc. of 0.533 M aqueous periodic acid solution. After being shaken thoroughly, the mixture is kept at 20-25° for twenty-four hours. About one mole of periodic acid per C H oOs unit of starch reacts to yield oxidized starch (LYI). The product is filtered, washed free from iodic acid and excess periodic acid with cold water, and dried at 40-50°. The yield is quantitative. Over 99% of the substance dissolves in forty parts of water at 100° during two hours [a]o = +9°. 

Aldehyde starches are prepared by treatment with periodic acid/periodate ions, which selectively oxidize the adjacent hydroxyl groups on carbon atoms 2 and 3 to aldehyde groups. Dialdehyde starch can react with cellulose by forming covalent hemiacetal and acetal bonds.40 It is primarily used as a wet strength agent in the production of tissue and other sanitary grades. 

Starch was oxidized by Jackson and Hudson,who used periodic acid at room temperature. Considerable study has recently been made of the oxidation of starch on a commercial basis, using electrolytically regenerated periodic acid. The reaction is carried out under what are normally drastic conditions for a periodate oxidation, namely pH 1.2-1.4 and 100°F, apparently without occurrence of any over-oxidation. Oxystarch is known commercially as dialdehyde starch. ... 

The uses of periodate-oxidized carbohydrates are thus far confined to uses for oxycelluloses and, more particularly, oxystarches ( dialdehyde starches ). Following the development of the electrolytic regenerative process for periodic acid, oxystarch has been produced commercially in the United States by the Miles Chemical Company of Elkhart, Indiana. 

A product made from renewable raw materials has also been active in this application. Oxidation of the amy-lopectin fraction of starch with periodic acid cleaves some vicinal diol structures to dialdehydes which can be oxidized further to dicarboxylic acids.273 For good activity... 

The halogens and their oxyacids probably are the most important oxidants used in the carbohydrate field. They are widely used as bleaching agents, but the mechanism of this action remains to be clarified. As reagents for preparatory purposes (particularly for aldonic acids and lactones) and for analytical procedures, they are very important. Periodic acid, discussed in a later section, has an important application for the elucidation of structures of carbohydrates. A number of valuable commercial products are made by treatment of polysaccharides with halogens, particularly chlorine or hypochlorous acid, but the nature of these actions, such as the modification of starch, has not been clarified. 

As shown in Figure 5.20, the oxidation of starch results in the addition of two aldehyde groups to individual glucose molecules within the polymer chain. The advantage of using periodic acid lies in the specificity of its oxidation. It facilitates the formation of aldehydes within the polysaccharide molecule. The extent of oxidation of the polysaccharide polymer can be controlled by, for example, the amount of oxidizer added, the duration of the oxidation process, and/or the temperature of the reaction. For example, the oxidation time needed for the oxidation of starch can be attained in about 24h. Specifically, at least about 15% of the hydroxyl groups are oxidized, and more specifically, about 35 to about 100% of the hydroxyl groups are oxidized [99]. 

The filtrate was adjusted to a pH of 9 by adding concentrated ammonia, and than a 1 N aqueous iodine-potassium iodide solution was added dropwise, whereby the tetrahydro-pyrimido-[5,4-d] pyrimidine obtained by hydrogenation with zinc in formic acid was converted by oxidation into 2,6-bis-(diethanolamino)-8-piperidino-pyrimido-[5/4-d]-pyrimidine. The completion of the oxidation was checked by means of a starch solution. The major amount of the oxidation product already separated out as a deep yellow crystalline precipitate during the addition of the iodine solution. After the oxidation reaction was complete, the reaction mixture was allowed to stand for a short period of time, and than the precipitate was separated by vacuum filtration, washed with water and dried. It had a malting point of 157°C to 158°C. The yield was 8.0 g, which corresponds to 95% theory. 

The following alternative procedure may be used to prepare a solution of disodium hydroxylaminedisulfonate. Sodium nitrite (15 g., 0.217 mole) and 41.6 g. (0.40 mole) of sodium bisulfite are added to 250 g. of ice. With stirring, 22.5 ml. (0.40 mole) of acetic acid is added all at once and the mixture is stirred for 90 minutes in an ice hath. At the end of the stirring period the reaction solution is pH 5 and a potassium iodide-starch test is negative. A solution of 50 g. (0.47 mole) of sodium carbonate in water (total volume 250 ml.) is added. This buffered solution of disodium hydroxylaminedisulfonate may be used for electrolytic oxidation. 

Of the myriad of modified starch systems tested, ranging from simple enzymically dextrinized starches to covalently attached amino acids and peptides onto dextrinized and/or oxidized (hypochlorite or periodate) corn starch bases, two polymers were selected as holding promise. The first system was a low dextrose equivalent (DE 5.7) enzyme-modified corn starch. The second starch-based polymer developed was a periodate-oxidized, amylase-dextrinized, covalently-attached phenylalanine glycoamine. 

Formic acid appears to show some selectivity in preferentially esterifying primary hydroxyl groups. Traquair161 describes the preparation of unstable starch formates. The monoformate is believed to be esterified at position 6. The periodate oxidation of monoformates of starch and limit dextrin indicates that ester linkage is predominantly... 

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