A rapid-throughput adaptable method for determining the monosaccharide composition of polysaccharides

Polysaccharides make up the largest non-water component of plant-based foods. Their ability to manipulate the gut microbiome and modulate the immune system has increased interest in the rapid elucidation of their structures. A necessary component for the structural characterization of polysaccharides is the determination of their monosaccharide composition. Current methods of monosaccharide analysis are not suitable for analyzing large sample-sets and are limited by their inability to analyze polysaccharides. We have developed a 96-well plate hydrolysis and derivatization procedure followed by a rapid and sensitive 10-min ultra-high performance liquid chromatography triple quadrupole mass spectrometry analysis capable of the absolute quantitation of 14 plant monosaccharides. Four polysaccharide standards, inulin, xyloglucan, arabinogalactan, and rhamnogalacturonan-I, which are commonly found in plants, were used to optimize and validate the method. The optimized conditions were applied to eight foods to show the method's reproducibility and ability to analyze complicated and insoluble polysaccharide mixtures. This approach will allow researchers to obtain accurate and absolute quantitation of monosaccharides in the large sample-sets that are required for agricultural, food, clinical, and nutrition-based studies.