title: Optimization of alkaline sulfite pretreatment and comparative study with sodium hydroxide pretreatment for improving enzymatic digestibility of corn stover.
abstract: In this study, alkaline sulfite pretreatment of corn stover was optimized. The influences of pretreatments on solid yield, delignification, and carbohydrate recovery under different pretreatment conditions and subsequent enzymatic hydrolysis were investigated. The effect of pretreatment was evaluated by enzymatic hydrolysis efficiency and the total sugar yield. The optimum pretreatment conditions were obtained, as follows: the total titratable alkali (TTA) of 12%, liquid/solid ratio of 6:1, temperature of 140 °C, and holding time of 20 min. Under those conditions, the solid yield was 55.24%, and the removal of lignin was 82.68%. Enzymatic hydrolysis rates of glucan and xylan for pretreated corn stover were 85.38% and 70.36%, and the total sugar yield was 74.73% at cellulase loading of 20 FPU/g and β-glucosidase loading of 10 IU/g for 48 h. Compared with sodium hydroxide pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 10.43%. Additionally, the corn stover pretreated under the optimum pretreatment conditions was beaten by PFI at 1500 revolutions. After beating, enzymatic hydrolysis rates of glucan and xylan were 89.74% and 74.06%, and the total sugar yield was 78.58% at the same enzymatic hydrolysis conditions. Compared with 1500 rpm of PFI beating after sodium pretreatment with the same amount of total titratable alkali, the total sugar yield was raised by about 14.05%.
authors.affiliation: †Liaoning Key Laboratory of Pulp and Papermaking Engineering, Dalian Polytechnic University, Dalian, 116034 Liaoning, China.|§CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 Shandong, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
authors.affiliation: §CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 Shandong, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Pang
authors.affiliation: †Liaoning Key Laboratory of Pulp and Papermaking Engineering, Dalian Polytechnic University, Dalian, 116034 Liaoning, China.|§CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 Shandong, China.
authors.forename: Haisong
authors.initials: H
authors.lastname: Wang
authors.affiliation: †Liaoning Key Laboratory of Pulp and Papermaking Engineering, Dalian Polytechnic University, Dalian, 116034 Liaoning, China.
authors.forename: Haiming
authors.initials: H
authors.lastname: Li
authors.affiliation: †Liaoning Key Laboratory of Pulp and Papermaking Engineering, Dalian Polytechnic University, Dalian, 116034 Liaoning, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Lu
authors.affiliation: †Liaoning Key Laboratory of Pulp and Papermaking Engineering, Dalian Polytechnic University, Dalian, 116034 Liaoning, China.
authors.forename: Meihong
authors.initials: M
authors.lastname: Niu
mesh_terms: D000468:Alkalies / Q000737:chemistry; D055162:Biocatalysis; D001709:Biotechnology / Q000379:methods*; D002480:Cellulase / Q000737:chemistry*; D004063:Digestion; D006868:Hydrolysis; D018547:Plant Stems / Q000737:chemistry; D012972:Sodium Hydroxide / Q000737:chemistry; D013447:Sulfites / Q000737:chemistry; D014866:Waste Products / Q000032:analysis*; D003313:Zea mays / Q000737:chemistry*; D001616:beta-Galactosidase / Q000737:chemistry*
chemical_list: D000468:Alkalies; D013447:Sulfites; D014866:Waste Products; D012972:Sodium Hydroxide; D001616:beta-Galactosidase; D002480:Cellulase
keywords: alkaline sulfite pretreatment; corn stover; enzymatic hydrolysis; total sugar yield