APPLICATION OF A NEW GC-MS METHOD FOR DETERMINIG ESTER CONTENTS FOLLOWING ALKALINE OR ENZYMATIC HYDROLYSIS OF SUGAR BEET PULP AND PECTIN

摘要

A new gas chromatography method with selective mass spectrometry detection is reported that applies three innovations for analysis of pectin esters - 1) stable deuterated isotopomers, 2) Carboxen-PDMS solid-phase microextraction fibers, and 3) headspace sampling - and separations based on a PoraPLOT Q capillary column. This method provides for simple, fast, and simultaneous determination of methanol and acetic acid released by pectin hydrolysis, and it can be applied to other classes of similarly esterified polysaccharides. This method has been further demonstrated as capable of detecting and simultaneously measuring enzyme activities of pectin acetylesterase and methylesterase. Finally, this method provides an important new analytical technology for use in research directed to developing new bioproducts from sugar beet cell wall polysaccharides and for monitoring enzyme activities in food and beverage processing.