Of maltotriose

PuUulan [9057-02-7] first described in detail in 1959, is a water-soluble extracellular a-D-glucan elaborated by the fungus yiureobasidiumpullulans (formerly Eullulariapullulans) (285). It is a linear polymer of maltotriose units linked from the reducing end of one trisaccharidic unit to the nonreducing end of the next trisaccharidic unit by a(l — 6) linkages (286) ... 

In these a-amylase reactions, glucose is not the primary product. Glucose is formed as a secondary product in the hydrolysis of maltotriose, maltotetraose and branched dextrins. Using 14C-reducing end labeled maltodextrins, G3 to G8, Robyt and French19 showed that porcine pancreatic a-amylase has different specificities for hydrolyzing the different linkages of the maltodextrins. The different frequencies for... 

Substrate Solution Dissolve 1.00 g of maltotriose (Sigma Chemical Co., Catalog No. M 8378) in Citrate Buffer in a 50-mL volumetric flask, and dilute to volume with Citrate Buffer. 

By interrupting the hydrolysis of y-CD at the appropriate moment, significant quantities of maltotriose can be obtained. The preparative liquid chromatographic technique makes the isolation of the oligomers possible in pure form and they can be used either as reference material in the synthesis of oligosaccharides or... 

Elsinan is an extracellular a-D-glucan produced by a strain of Elsinoe leucospila from sucrose or other carbohydrates in an aerobic condition. Methylation studies. Smith degradation, partial acid hydrolysis and acetolysis established that elsinan is composed mainly of maltotriose residues and maltotetraose residues (minor) joined by a-(1 3)-linkages. 

Other glucans encountered in fungi are e 1 sinan(64) from Els i noe leucospi1 a which is constituted of maltotriose units linked by (1 -3)-a linkages. It is water soluble and gels at concentrations greater than 2%. No x-ray diffraction study or morphological information is available at this time. 

We also observe a negative band at 190 nm in the solution spectrum of pullulan (Table II), but at much reduced intensity relative to amylose. We take this band to originate in the same local conformation responsible for the low energy dichroism in amylose. The intensity, however, is modified by the presence of l->6 linkages between repeating sequences of maltotriose. 

Cycloamyloses. — The Raman spectrum of cyclohexa-amylose has been compared with those of maltotriose and maltose, and structural implications of the spectra discussed. 

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