Improving Biomass Conversion Efficiency by Modifying Lignin so Plant Cell Walls Are More Digestible and Fermentable

Objective

Lignocellulosic biomass is a very desirable feedstock for biofuel production. If the fermentation process for lignocellulose could be optimized conversion of this biomass could yield 25 to 50 billion gallons of ethanol or other biofuels per year. However lignocellulose which is composed of lignin cellulose and hemicelluloses is resistant to chemical or enzymatic hydrolysis. This resistance is a key limiting step in the conversion of biomass into fermentable sugars. Currently pretreatment steps which involve heating the biomass to high (170°C or greater) temperatures using large amounts of water and/or using caustic acids or bases are required before biorefining of lignocellulosic biomass. Lignin also must be degraded or modified during paper manufacturing to make the desirable cellulose fibers available. But current pulping techniques require high amounts of energy harsh chemicals or large quantities of wood and can result in poor quality paper. Wisconsin researchers have demonstrated that lignin may be engineered to be more digestible and fermentable by structurally altering the lignin so its monomer complement incorporates coniferyl and/or sinapyl ferulate. This allows biomass polysaccharides to be utilized more efficiently and sustainably which should reduce inputs for energy pressure vessel construction and bleaching during papermaking and lessen pretreatment and enzyme costs associated with biomass conversion. Applications: 1) Conversion of lignocellulosic biomass to biofuels and industrially important chemicals 2) Production of pulp for papermaking 3) Production of animal feeds and forages

Benefits

1) By reducing the severity of the required pretreatment step this discovery should lead to savings in both energy costs and water consumption. 2) May enable sustainable local processing without massive facility costs 3) Processing low-density plant materials locally may decrease transportation costs and reduce greenhouse emissions. 4) May make animal feed more digestible 5) Applicable to all types of plants

Date of release