ARS | Publication request: Improved analysis of simple sugars and galacturonic acid in hydrolyzed citrus waste

Submitted to: Subtropical Technology Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: October 18, 2009
Publication Date: October 22, 2009
Citation: Widmer, W. 2009. Improved analysis of simple sugars and galacturonic acid in hydrolyzed citrus waste. Subtropical Technology Conference Proceedings. 60:13-14.

Technical Abstract: While the most accurate method for analysis of sugars in biomass is based on gas chromatography of trimethylsilane or alditol acetate derivitives of sugars, the derivation method is time consuming and laborious. In comparison, sample preparation for sugar analysis using liquid chromatography is a simple water extraction procedure, however analysis of hydrolyzed biomass materials are either poorly resolved for some sugars or analysis times are long. High performance ion moderated partition (HPIMP) chromatography using a lead column does not give good resolution for some sugars present in enzyme or chemical hydrolysates of biomass. In addition, galacturonic acid (an indicator of pectin hydrolysis) is retained and not eluted by this column. Since pectin is a major polysaccharide component in citrus waste, galacturonic acid analysis is of interest and requires a separate analytical technique if a lead based HPMIP column is used for sugar analysis. High performance anion-exchange chromatography using a Dionex PA-1 column with pulsed amperomeric detection (PAD) provides a much better separation of mono and disaccharide sugars, and a gradient method was developed using a post column addition that also allows analysis of galacturonic and other acidic sugars along with neutral simple sugars in hydrolyzed materials. However, the time required for analysis using this method is lengthy at 70 min. The method was modified to reduce analysis time to 40 min, equivalent to the analysis time required using HPIMP. The method gives good resolution for arabinose, rhamnose, galactose, xylose, glucose, fructose, sucrose, cellobiose, galacturonic acid, and glucuronic acid and its application to hydrolyzed citrus waste materials will be discussed.