Periodate Oxidation of Polysaccharides

Vicinal alcohol groupings in polysaccharides can be oxidized by periodate to cleave the carbon-carbon bond and produce two aldehyde groups. Starch is the principal polysaccharide that has been oxidized to produce dialdehyde starch (reaction 7.22) [15]. The degree of oxidation can be controlled by the amount of 

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Trifluoroacetic acid is volatile, and thus readily removed. This acid was used by Albersheim and coworkers for the hydrolysis of plant cell-walls,39 and has since been employed for cell walls,40-43 plant mucilages,44 blood-group oligosaccharides,45 peptidogalactoman-nans,46 heparin,47 and disaccharides in blood and urine.48,49 It has also been suggested as an alternative to 6 M hydrochloric acid in the determination of amino sugars,50 and for the hydrolysis of polyalcohols produced by periodate oxidation of polysaccharides.503 Lee... 

The linear dextran has also been used in investigating the mechanism of the periodate oxidation of polysaccharides. The results support the proposal that inter-residue, hemiacetal formation is a general occurrence in the later stages of the oxidation.128... 

The periodate oxidation of carbohydrates, an important analytical technique, has been reviewed earlier in this Series.73 The dialdehydes obtained on periodate oxidation of polysaccharides have also been discussed.74 The requisite for the degradations to be discussed here is that part of the sugar residues in a polysaccharide are not oxidized by periodate and can be obtained separated from the oxidized residues as mono-, oligo-, or poly-saccharide derivatives after some chemical treatment. Characterization of these products may then give significant structural information. 

Painter and coworkers demonstrated that inter-residue hemiacetals may be formed during the periodate oxidation of polysaccharides,... 

The polyaldehydes obtained on periodate oxidation of polysaccharides are alkali-labile, as discussed in previous articles in this Series.74,103 The products are, however, generally intractable mixtures, and this mode of degrading polysaccharides (with alkali) has... 

Kristiansen, K.A., Potthast, A., Christensen, B.E. Periodate oxidation of polysaccharides for modification of chemical and physical properties. Caibohydr. Res. 345, 1264-1271 (2010)... 

Oxidation of polysaccharides is a far more attractive route to polycarboxylates, potentially cleaner and less cosdy than esterification. Selectivity at the 2,3-secondary hydroxyls and the 6-primary is possible. Total biodegradation with acceptable property balance has not yet been achieved. For the most part, oxidations have been with hypochlorite—periodate under alkaline conditions. In the 1990s, catalytic oxidation has appeared as a possibiUty, and chemical oxidations have also been developed that are specific for the 6-hydroxyl oxidation. 

The oxidative cleavage of v/c-diols to give two carbonyl functions (Eq. 5.3) by periodates was first observed by Malaprade and has since been widely applied to the carbohydrate area.50 Since both the reagent sodium periodate and the carbohydrate substrate are water soluble, the reaction is usually carried out in aqueous media.51 The reaction has been applied to polysaccharides such as starch.52 The periodate oxidations of sodium alginate in water as well as a dispersion in 1 1 ethanol-water mixture have been compared.53 Because sodium alginate forms a highly viscous solution, the oxidation was observed to be more extensive in ethanol-water. 

Oxidation of polysaccharides using 10 mM or greater concentrations of sodium periodate at room temperature results in the cleavage of adjacent hydroxyl-containing carbon-carbon bonds on other sugars besides just sialic acid residues (Lotan et al., 1975). High concentrations... 

The reaction of these aldehydes, derived from periodate oxidation, with carbonyl reagents has also been investigated. Studies 147 148 were made on oxidized laminarin, a (1 —> 3)-linked polysaccharide, in which only the terminal residues had been oxidized. The addition of phenylhydrazine acetate detached the remainder of the terminal residue as glyoxal phenyl-osazone. When the aldehydic compounds derived from the periodate oxidation of raffinose and trehalose818a were reacted with p-nitrophenylhydrazine, the authors were surprised to find that one molecule of oxidized raffinose, containing six aldehydic functions, reacts with only three molecules of the reagent, and that the four aldehydic functions of the oxidized trehalose molecule react with only two. The reactions of periodate-oxidized carbo-... 

Polysaccharides.—Very few oxidations of polysaccharides have been carried out with lead tetraacetate, a situation in marked contrast to the voluminous literature on polysaccharide oxidations with periodate.22 The main reason for this discrepancy has undoubtedly been the fact that polysaccharides are insoluble in the solvents generally used for lead tetraacetate oxidation. 

V. V. Barbakadze and A. I. Usov, Polysaccharides of algae. 26. Methylation and periodate oxidation of a polysaccharide from the red seaweed Grateloupia divaricata Okam., Sov. J. Bioorg. Chem., 4 (1978) 808-813(English translation from Bioorg. Khim., 4 (1978) 1100-1106). 

A. I. Usov, L. I. Miroshnikova, and N. K. Kochetkov, Polysaccharides of algae. 10. Periodate oxidation of a polysaccharide from Laingia pacifica Yamada, Zh. Obshch. Khim., 42 (1972) 1623-1630 (in Russian). 

The structures of the disaccharides and higher saccharides (obtained by partial hydrolysis of polysaccharides) can be examined by periodate or lead tetraacetate oxidation. Ahlborg studied the periodate oxidation of disaccharides and starch dextrins in 0.5 N sulfuric acid. Since the intermediate formate esters were hydrolyzed, these conditions were favorable for overoxidation. The (1 — 4)- and (1 —> 6)-linkages in the starch dextrins were each found to be associated with a characteristic consumption of oxidant. Neumtiller and Vasseur studied periodate oxidation in solutions of various acidities, from strongly acid to neutral, and showed that there were differences between different types of disaccharides. 

Periodate oxidation of a reducing polysaccharide at an elevated temperature, using a phosphate buffer of pH 8 to facilitate the hydrolysis of the... 

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