Maltotriose liberated from

B-chains until they are acted on by R-enzyme, when maltose or malto-triose will be produced from the residual A-chain, and linear dextrins from the B-chains. The amount of maltose or maltotriose liberated on treating the /3-limit dextrin with R-enzyme will be a measure of the number of A-chains in the molecule, and from these data, the ratio of A B chains in the molecule can be calculated.220 Peat concluded that multiple branching is an intrinsic part of the amylopectin structure, as the observed yield of these sugars was greater than expected for a singly-branched structure. It should be noted that glycogen has been shown by similar enzymic methods to possess a truly random structure.221... 

Figure 1. Photograph of a paper chromatogram of the products liberated from maltotriose by glucoamylase...

The /8-amylase starts from the non-reducing end group and attacks chains with maltose linkages. Only maltose is liberated. Anomalies in the constitution of the chain molecule, such as isomaltose linkages, stop the enzyme action. The length of the chain plays no significant role. Maltotriose and maltose are not attacked. The enzyme is an exo amylase. ... 

Penicillium oxalicum was shown to produce two forms of glucoamylase and an a-D-glucosidase. The a-D-glucosidase has been isolated from the mycelia in an electrophoretically homogeneous form, and its properties have been investigated. The enzyme had a pH optimum at 3.5 with maltose as substrate. The enzyme hydrolysed maltose, maltotriose, phenyl a-maltoside, isomaltose, panose, isomaltotriose, amylose, and soluble starch liberating D-glucose, but not... 

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