Arthur J. Ragauskas
Oak Ridge National Laboratory, USA
Title: Next Generation of Low Recalcitrance Plants for BioFuels
Biography
Biography: Arthur J. Ragauskas
Abstract
The recalcitrance of biomass is one of the greatest difficulties in the overall conversion of biomass to biofuels. To-date this requires costly pretreatment technologies that frequently lead to the generation of fermentation inhibitors and waste streams that need be treated in an environmental acceptable manner, incurring additional costs. The minimization of native biomass recalcitrance is clearly related to tailoring the structure of the starting bioresource (1) over the past decade, we have examined what plant cell parameters are involved in plant recalcitrance and have clearly determined that this is a multi-structural feature involving cellulose ultrastructure/degree of polymerization (DP), hemicellulose content and structure, lignin structure and content, lignin-carbohydrate complexes and plant cell wall accessibility. But it is also clear not all these parameters are of equal importance (2). examining the structural fidelity of ‘wild’ popular resources, we were able to demonstrate that the structure of lignin plays a key component in the overall recalcitrance of this feedstock, of special significance was the nature of inter-unit lignin bonding structures along with the structure of hemicelluloses. Both of these components undergo significant changes when undergoing acidic pretreatments which provide a biomass with increased accessibility and reactivity to cellulose. This presentation will examine the plant cell features and the advances in analytical chemistry needed to examine these features. These advances in the understanding of biomass recalcitrance have now facilitated key advances in accelerated engineering of low-recalcitrance plants that have now been developed in green house and controlled farm sites. In both case, the design of plants with low-reactance cell wall features has been demonstrated which in turn results in higher biofuel yields from a cellulose den construction/fermentation approach. Recommendations are made for next generation of plants will lower costs and improve the overall conversion of biomass to biofuels.