Amylase action

Acarbose itself is hydrolyzed by B. stearothermophilus maltogenic amylase at the first glycosidic linkage from the reducing end to give D-glucose and acarviosine-glucose 

Uchida et al.220b reported the synthesis of 6m-deoxy maltodextrins by B. macerans CGTase transglycosylation reactions between mono-6-O-p-toluene sulfonyl cyclomal-tohexaose and maltose. The best inhibitors for human salivary a-amylase and human pancreatic a-amylase were 6m-deoxy maltotetraose and 6m-deoxy maltopentaose. 

The most potent inhibitors of a-amylases to date are acarbose analogs in which maltohexaose (G6) and maltododecaose (G12) have been added to the C4-hydroxyl group at the non-reducing end cyclohexitol of acarbose, by the B. macerans CGTase catalyzed reaction of cyclomaltohexaose with acarbose.2200 The maltohexaose analog was 1.6- to 2.2-times more potent than the maltododecaose analog. All of the 

Kj values, however, were in the nanomolar range, with the Kj for the maltohexaosyl acarbose, 33 nM for A. oryzae a-amylase, 37 nM for B. amyloliquefaciens a-amylase, 14nM for human salivary a-amylase and 7.0nM for porcine pancreatic a-amylase. These inhibition constants represented relative inhibitory potency over acarbose of 8200-, 351 -, 90- and 114-times, respectively for the four a-amylases.220d 

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Table I. Oligosaccharide Compositions Prepared from Starches by Thermal Stable Alpha-Amylase Actions ...

Thoma, J.A. and Koshland, D.E. Jr. (1960) Stereochemistry of enzyme, substrate, and products during (3-amylase action. /. Biol. Chem., 235, 2511. 

Hexadiene-3,4-dioI, II, 108-111 Hexahexosan Pringsheim, /3-amylase action on, III, 267... 

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