An Acetate-Hydroxide Gradient for the Quantitation of the Neutral Sugar and Uronic Acid Profile of Pectins by HPAEC-PAD without Postcolumn pH Adjustment

作者：Nagel Andreas; Sirisakulwat Suparat; Carle Reinhold; Neidhart Sybille^*

来源：Journal of Agricultural and Food Chemistry, 2014, 62(9): 2037-2048.

DOI：10.1021/jf404626d

• galacturonic acid
• anion exchange chromatography
• pectin
• hydrolysis
• neutral sugar
• validation

An HPAEC-PAD method was developed and validated to quantitate seven neutral sugars and two uronic acids of hydrolyzed pectic polysaccharides without postcolumn pH adjustment. Due to a short gradient phase minimizing the ion concentrations after equilibrating the CarboPac PA20 column with sodium acetate and hydroxide, subsequent isocratic separation of the neutral sugars was characterized by almost baseline resolution of rhamnose and arabinose (1.45 +/- 0.15) and xylose and mannose (1.21 +/- 0.02) at their maximal concentrations. Linearity was shown (R-2 = 0.9975-0.9998) for the relevant ranges (0.28-30.3 mu mol L-1; galacturonic acid, 1.7-128 mu mol L-1) above the limits of detection (30-81 nmol L-1; galacturonic acid, 179 nmol L-1) and similar to 3.8 times higher limits of quantification. Conformity of the findings for four pectins after methanolysis plus hydrolysis in trifluoroacetic acid with those of reference procedures (total uronic acids, 95-102%; total neutral sugars, 97-105%) proved the accuracy.

• 出版日期2014-3-5