Abstract
As revealed by NMR spectroscopy (after ultrasonic degradation) and HPLC (after total hydrolysis) an arabinoxylan (AX) containing 74.8% Xyl p and 23.2% Ara f was isolated from Ispaghula ( Plantago ovata) by soaking the seed husk with water, extraction with aqueous sodium hydroxide and coagulation with acetic acid. The AX with a molar mass of 364,470 g/mol shows high swelling ability in water. The carboxymethylation of AX was carried out heterogeneously with sodium monochloroacetate in the presence of aqueous sodium hydroxide. The reaction parameters were varied in terms of slurry medium, molar ratio, temperature, time, and sodium hydroxide concentration. For comparative studies, carboxymethylation of arabinan was carried out. In order to determine the total degree of substitution (DS) and mole fractions of the repeating units of carboxymethyl arabinoxylan (CMAX) and of carboxymethyl arabinan, HPLC and 1H NMR spectroscopic investigations after total hydrolysis were carried out. DS values for CMAX as high as 1.81 were achieved. CMAX is water soluble starting at DS of 0.33.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
