Aye Aye Myint
Seoul National University, Republic of Korea
Title: Efficient techniques for woody biomass fractionation to enhance enzyme accessibility
Biography
Biography: Aye Aye Myint
Abstract
As cellulosic ethanol has achieved economic viability, the development of valuable products aside from biofuels from all main components of woody biomass, including cellulose, hemicellulose, and lignin, has gained traction. However, refining of woody biomass on industrial scales has not been realized because the accompanying lignin, hemicellulose, and extractives hinder enzyme and microbial degradation. Hence, the development of new fractionation technologies to separate woody biomass into its core components and for the facilitation of research on the production of specific marketable downstream products are of great importance to ensure a profitable biorefineries on the industrial scale. Here, a novel method has been developed for fractionating cellulose microfibrils from forest residue (tulip tree sawdust) to enhance cellulose digestibility, particularly at minimum enzyme loading. This method involved three main stages: selective hemicellulose solubilization by subcritical water (subCW) pretreatment, delignification of the subCW-pretreated solids using the formosolv process, and deformylation/bleaching of the cellulose pulp with alkaline hydrogen peroxide solution. In the subCW pretreatment process, the efficiency of process was assessed by using the severity factor, R0, which describes the combined effect of temperature and time. The chemical composition, physicochemical properties and enzymatic digestibility of the pretreated products can be characterized and strongly correlated with the pretreatment severity. This study clearly showed that the removal of structural barriers to the enzyme attack was the dominant factor affecting enzyme accessibility to the substrate. Additionally, cellulose swelling had the greatest effect on the enzymatic hydrolysis efficiency of delignified pulp obtained by the Formosolv process.