Rapid measurement of xylose and glucose for monitoring corn stover fermentation in bioethanol production

Acid-treated corn stover produces a variety of fermentable sugars that include glucose, xylose, mannose, arabinose, cellobiose, and galactose.   HPLC is commonly used to measure glucose and xylose, which are important markers for evaluating the progress and efficiency of ethanol fermentation processes.  The HPLC method is accurate and precise; however, it requires significant sample pretreatment and analytical cycle times ≥ 30 minutes.  A YSI Biochemistry Analyzer, configured with glucose oxidase and pyranose oxidase immobilized enzyme membranes, was evaluated for its ability to simultaneously measure glucose and xylose during fermentation of pretreated corn stover in a bioethanol production process.   In this study filtered corn stover samples were periodically measured for glucose and xylose over a 48-hour period during a lab-scale bioethanol fermentation.  Samples were analyzed on both a YSI Biochemistry Analyzer and an HPLC.  Comparability of the two analytical methods were evaluated with regards to precision and analysis time.   A strong, positive correlation of the two methods was demonstrated.  The YSI Biochemistry analyzer performed simultaneous analysis of glucose and xylose within one minute, providing a rapid, precise analytical alternative to the HPLC analytical method.