Bioresource Technology, Volume 130, February 2013, Pages 578-583.
Haiyan Yang, Kun Wang, Wei Wang, Run-Cang Sun
Institute of Biomass Chemistry and Technology, College of Material Science and Technology, Beijing Forestry University, Beijing 100083, China and
Institute of Microbiology, Beijing Forestry University, Beijing 10083, China and
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
Successive treatments with fungus and alkali were proposed to reduce the recalcitrance and improved the enzymatic digestibility of triploid poplar. Biopretreatment with Trametes velutina D10149 for 0, 4, 8, 12 and 16 weeks gradually degraded hemicelluloses and lignin, and improved the digestibility of cellulose from 4.0% to 19.5% with the increasing dry mass loss of lignocelluloses from 15.5% to 53.4%. Combining with alkaline fractionation, biopretreatment for 4 weeks significantly enhanced the availability of cellulose and achieved a maximum glucose yield (38.8% of the original cellulose) with a dry mass loss of 24.4%. The BET surface area of lignocelluloses increased from 1.7 to 10.6 m2/g after combination of 8 weeks biopretreatment and alkaline fractionation. Moreover, alkaline fractionation removed amorphous and low molecular components, which incurred a higher crystalline index and narrower molecular weight distribution of residual carbohydrates in synergistically treated samples as compared to biopretreated samples.