Maltose, general

Amylase occurs in many plants, such as barley, wheat, rye, soy beans, and potatoes, where it is generally accompanied by some a-amylase. [ -Amylase initiates hydrolysis at the nonreducing end of an amylose or amylopectin chain, and removes maltose units successively until the reducing end of the molecule is encountered in amylose or a branch is met in amylopectin. ( -Amylase is used commercially in the preparation of maltose symps. After P-amylase hydrolysis of amylopectin there remains a P-amylase limit dextrin. ( -Amylase has been used as a probe of the fine stmcture of amylopectin (43-46). 

Com symps [8029-43 ] (glucose symp, starch symp) are concentrated solutions of partially hydrolyzed starch containing dextrose, maltose, and higher molecular weight saccharides. In the United States, com symps are produced from com starch by acid and enzyme processes. Other starch sources such as wheat, rice, potato, and tapioca are used elsewhere depending on avadabiHty. Symps are generally sold in the form of viscous Hquid products and vary in physical properties, eg, viscosity, humectancy, hygroscopicity, sweetness, and fermentabiHty. 

Fermentabihty of com symps by yeast is important in certain food appHcations, eg, baking and brewing. The fermentable sugars present in corn symp are dextrose, maltose, and maltotriose. Fermentabihty of maltose or maltotriose depends on the specific fermentation process and organism. In general, greater fermentabihty is obtained at higher DE levels. 

XIV. Generalization of the Relationship between the Stbuctubes of Turanose and Maltose... 

In41 the foregoing proof of the structure of turanose, the generally accepted structure of maltose which has come from the evidence supplied... 

Rm indicates in a general way the D-glucosyl component of maltose, and Rt that of turanose. One OH becomes O when a position of union is specified.)... 

General protease, a-amylase, and exoglucanase activities were estimated using hide powder-, amylose-, and celliilose-azure substrates, respectively, as described earlier (49). Here, standard curves were developed for the hydrolysis of each azure-linked substrate by standard enzymes of known activity. By this method, one cellulose-azure hydrolysis unit corresponds to one filter paper unit, one unit of hide powder-azure activity corresponds to the hydrolysis of 1.0 nmole of iV-benzoyl-L-tyrosine ethyl ester (BTEE) per min, and one amylose-azure unit of activity corresponds to the hydrolysis of 1.0 nmole of maltose from starch per 30 min. 

With simple compounds, the trimethylsilylation reaction is rapid, but, if the reaction proceeds slowly, short reaction-times lead to incomplete substitution this is generally manifest on the gas chromatogram because of the presence of an unexpectedly large number of peaks.117 Maltose has been reported to require reaction for at least 30 minutes,118 and the time needed for complete trimethylsilylation of amino sugars has been examined by Oates and Schrager.36... 

The dehydration of the enediols is a reaction subject to general acid-base catalysis. The deoxyaldosulose 7a has been isolated from 3-O-benzyl-D-glucose34 and from D-fructose35 after treatment with alkali, and from D-fructose35 and various Amadori products8 after treatment with acid. The most successful preparation of 7a has been by way of amine addition compounds an improved procedure has been reported.36 Compound 9a has been isolated as a product of the alkaline treatment of both cellobiose37 and maltose.38 The isolation of 10a has not been reported, but it has been synthetically39 prepared. 

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