Measurement and Control Strategies for Sterol Glucosides to Improve Biodiesel Quality: Isolation and Characterization of Acylated Steryl Glucosides in Oilseed Crops of the Pacific Northwest

摘要

Acylated steryl glucosides (ASG), a form of phytosterols, have been identified in a variety of agricultural products, including the oilseeds of soybean and rapeseed. Currently, there are limited data available on the quality and quantity of phytosterols in oilseed crops. During biodiesel production, the esterification of ASG in oil extracts forms steryl glucosides (SG). These steryl glucosides in low concentrations (less than 50ppm) have been implicated in agglomeration of contaminates leading to subsequent filter clogging in biodiesel applications. Limited methods exist for the direct isolation and characterizations of ASG. Methods rely on multistep extraction, saponification, acidification and derivatization for evaluation with GC-MS. The objective of this study is to characterize the ASG in agronomically significant oilseed crops of the Pacific Northwest. In this study, HPLC-ESI-MS and HPLC-APCI-MS techniques were evaluated as characterization tools. Oilseeds have been solvent extracted; continuing work is the characterization using the validated MS techniques of the glycolipid fraction after isolation with preparatory chromatography. Characterization of these natural products is important to the industry for developing strategies to minimize agglomeration in biodiesel.