A Rapid Modified Method for Compositional Carbohydrate Analysis of Lignocellulosics by High pH Anion-Exchange Chromatography with Pulsed Amperometric Detection (HPAEC/PAD)

Abstract

During the last decade, high pH anion exchange chromatography with pulsed amperometric detection (HPAED/PAC) has gained increasing acceptance as the method of choice for analysis of neutral sugars commonly occurring in woods, pulps, and other lignocellulosics. This paper describes modified chromatographic conditions and discusses other critical factors that improve the precision and efficiency of this application. The method involves a controlled loading of acetate onto the column prior to equilibration with water and injection of sample. In-line solid-phase extraction is used to remove hydrophobic substances that have the potential to foul the analytical column. Critical operational parameters for the successful application of the method include a metal-free flowpath and a consistent application of anions with sample. Resolution of rhamnose is achieved while maintaining the resolution of xylose and mannose. Simplified sample pretreatment allows a ca. five-fold increase in sample through-put compared with gas chromatography of derivatized sugars or to partition chromatography. Run times are less than half those of the widely used hydroxide reverse gradient method for HPAEC/PAD analysis of wood sugars. Long-term system performance data indicate that the method is highly precise and robust. The acetate loading method affords better precision than those of other HPAEC/PAD methods and of gas chromatographic analysis of alditol acetate derivatives by Tappi Method T249 cm-85

Characterization of nonderivatized plant cell walls using high‐resolution solution‐state NMR spectroscopy

“…[47] For the pine, no data exists to support acetates on guaiacyl lignin. Thus, the acetates are expected to be on the mannans (~10% of loblolly pine hemicelluloses), [45] in particular galactoglucomannan, the principal hemicellulose component in gymnosperms.…”

“…Aspen syringyl units are only ~4% acetylated [43,44] ; acetylated xylans may contribute largely to the acetate content. The major component of angiosperm hemicelluloses is an O-acetyl-4-Omethylglucurono-β-D-xylan (~16% of aspen and ~13% of kenaf cell wall), [45] where about 7 out of 10 xylose residues contain an O-acetyl group at C-2 or C-3. Ac-β-D-Xylp) H-2/C-2 and H-3/C-3 correlations (shown in Fig.…”

Determination of organic acids, carbohydrates and sweeteners in food products and biologically active additives by HPLC

“…Для определения низких концентраций угле-водов (10-100 пмоль) методом обращенно-фазовой высокоэффективной жидкостной хроматографии (ОФ ВЭЖХ) обычно прибегают к дериватизации и использованию высокочувствительных детек-торов [1][2][3][4][5]. Существуют также соответствующие газохроматографические методики [6].…”

Effects of Lignin Removal on Substrate Enzymatic Hydrolysis of SPORL-high-pH Pretreated Bagasse

“…The concentration of glucose from enzymatic hydrolysis was measured using high-performance anion exchange chromatography (ICS-3000, Dionex, Sunnyvale, CA) equipped with pulsed amperometric detection (HPAEC-PAD) and an anion exchange column (Dionex, CarboPac PA1) (Davis 1998). Detailed gradient and other chromatography conditions are referenced elsewhere (Davis 1998).…”

“…Detailed gradient and other chromatography conditions are referenced elsewhere (Davis 1998). The pretreatment solid yield was determined by the gravimetric method after balancing the moisture content of the collected solid substrates and original bagasse initially used in pretreatment experiments.…”