Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/5/2007
Publication Date: 6/5/2007
Citation: Haney, L.J., Scott, M.P., Lamkey, K.R., Coors, J.G., Lorenz, A.J. 2007. Developing an assay to determine bioavailability of lignocellulose in corn stover. In: Proceedings of Corn Utilization and Technology Conference, June 5-7, 2006, Dallas, Texas. 2006. CDROM.
Technical Abstract: Lignocellulose is said to be the most abundant compound on earth and is an excellent renewable feedstock for the production of ethanol as an alternative fuel source. Corn stover is made of lignocellulose and may prove to be an essentially free renewable energy resource. The goal of this research is to develop a high throughput method for predicting the suitability of corn stover for lignocellulosic conversion to ethanol. The assay consists of a dilute sulfuric acid pretreatment and a process we call simultaneous saccharification and catabolism (SSC). In this process, enzymes are used to break down the hemicellulose and cellulose fractions of the stover to sugars which are metabolized by a bacterial strain, E. coli strain CA8404. This strain has been modified to produce green fluorescent protein (GFP) and to enable catabolism of both five- and six-carbon sugars. Growth of this strain is limited by carbon in the hydrolysis reaction, so fluorescence is proportional to the level of sugars released by hydrolysis. We reason that the level of sugars produced in this hydrolysis should be a good predictor of suitability of a sample as a fermentation feedstock. The germplasm selected for evaluation by the assay represents a broad spectrum of biomass yield based on yield trials, and composition based on in vitro digestibility tests. This high throughput method may enable breeders to select varieties with improved suitability for lignocellulose conversion and could lead to higher ethanol yields.