Low-viscosity α-d-glucan fractions derived from sucrose which are resistant to enzymatic digestion
1992; Elsevier BV; Volume: 19; Issue: 4 Linguagem: Inglês
10.1016/0144-8617(92)90077-4
ISSN1879-1344
Autores Tópico(s)Enzyme Production and Characterization
ResumoAlternan is the name given to the alternating α(1→3), α(1→6)-linked d-glucan produced from sucrose by the extracellular enzyme system of Leuconostoc mesenteroides NRRL B-1355. The polysaccharide can be produced fermentatively or by cell-free enzyme preparations. Alterman is resistant to hydrolysis by known endoglucanases, and is a poor substrate for most exoglucanases. Although its viscosity is lower than that of commercial dextran, concentrated aqueous solutions (> 12–15% w/v) are still difficult to attain due to high viscosity. Sonication of native alternan lowers its molecular weight from > 107 to < 106. The sonicated material can be dissolved in water to give solutions of 50% (w/v) or greater. These solutions exhibit rheological properties similar to aqueous solutions of gum arabic. A ‘limit alternan’ produced by hydrolysis with isomaltodextranase has an average molecular weight of approximately 3500, and is rheologically similar to maltodextrins of degree of polymerization (D.P.) approximately 10.
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