title: Effects of green liquor pretreatment on the chemical composition and enzymatic digestibility of rice straw.
abstract: Green liquor (Na2S+Na2CO3, GL) pretreatment is a proven pathway to improve the enzymatic saccharification for the production of bioethanol. In this work, the effects of GL pretreatment on the chemical composition and enzymatic digestibility of rice straw at various total titratable alkali (TTA) charge and temperature were investigated. The GL pretreatment showed excellent performance in high polysaccharides retention and delignification selectivity. Under the optimized GL pretreatment condition (4% TTA charge, 20% sulfidity and 140°C), 92.5% of glucan, 82.4% of xylan and 81.6% of arabinan in rice straw were recovered with a delignification of 39.4%. The maximum sugar yields of 83.9%, 69.6% and 78.0%, respectively for glucan, xylan and total sugar, were achieved at the same GL pretreatment condition with an enzyme loading of 40 FPU/g-substrate. The results suggested that GL pretreatment is a practicable method for rice straw to enhance enzymatic saccharification for bioethanol production.
authors.affiliation: Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China. Electronic address: gufeng8411@gmail.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Gu
authors.forename: Wangxia
authors.initials: W
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Jing
authors.forename: Yongcan
authors.initials: Y
authors.lastname: Jin
mesh_terms: D000468:Alkalies / Q000494:pharmacology; D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000096:biosynthesis; D002480:Cellulase / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000378:metabolism; D004798:Enzymes / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis / Q000187:drug effects; D008031:Lignin / Q000302:isolation & purification; D012275:Oryza / Q000737:chemistry* / Q000187:drug effects; D013696:Temperature; D017186:Titrimetry; D014866:Waste Products / Q000032:analysis*; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D000468:Alkalies; D002241:Carbohydrates; D004798:Enzymes; D014866:Waste Products; D008031:Lignin; D001617:beta-Glucosidase; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases
keywords: Delignification; Enzymatic digestibility; Green liquor pretreatment; Rice straw; Sugar yield