Efficient sugar release by the cellulose solvent-based lignocellulose fractionation technology and enzymatic cellulose hydrolysis.
Efficient liberation of fermentable soluble sugars from lignocellulosic biomass waste not only decreases solid waste handling but also produces value-added biofuels and biobased products. Industrial hemp, a special economic crop, is cultivated for its high-quality fibers and high-value seed oil, but its hollow stalk cords (hurds) are a cellulosic waste. The cellulose-solvent-based lignocellulose fractionation (CSLF) technology has been developed to separate lignocellulose components under modest reaction conditions (Zhang, Y.-H. P.; Ding, S.-Y.; Mielenz, J. R.; Elander, R.; Laser, M.; Himmel, M.; McMillan, J. D.; Lynd, L. R. Biotechnol. Bioeng. 2007, 97 (2), 214- 223). Three pretreatment conditions (acid concentration, reaction temperature, and reaction time) were investigated to treat industrial hemp hurds for a maximal sugar release: a combinatorial result of a maximal retention of solid cellulose and a maximal enzymatic cellulose hydrolysis. At the best treatment condition (84.0% H3PO4 at 50 degrees C for 60 min), the glucan digestibility was 96% at hour 24 at a cellulase loading of 15 filter paper units of cellulase per gram of glucan. The scanning electron microscopic images were presented for the CSLF-pretreated biomass for the first time, suggesting that CSLF can completely destruct the plant cell-wall structure, in a good agreement with the highest enzymatic cellulose digestibility and fastest hydrolysis rate. It was found that phosphoric acid only above a critical concentration (83%) with a sufficient reaction time can efficiently disrupt recalcitrant lignocellulose structures.
Moxley
Geoffrey
G
Biological Systems Engineering Department, Virginia Polytechnic Institute and State University, 210-A Seitz Hall, Blacksburg, Virginia 24061, USA.
Zhu
Zhiguang
Z
Zhang
Y-H Percival
YH
D002188:Cannabis / Q000737:chemistry; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000032:analysis* / Q000302:isolation & purification; D002480:Cellulase / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism*; D005591:Chemical Fractionation / Q000379:methods; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008031:Lignin / Q000302:isolation & purification*; D010756:Phosphoric Acids; D012997:Solvents; D013696:Temperature; D013997:Time Factors
D002241:Carbohydrates; D010756:Phosphoric Acids; D012997:Solvents; C036909:lignocellulose; D002482:Cellulose; D008031:Lignin; C030242:phosphoric acid; D002480:Cellulase