title: Fractionation of enzymatic hydrolysis lignin by sequential extraction for enhancing antioxidant performance.
abstract: The heterogeneity of lignin chemical structure and molecular weight results in the lignin inhomogeneous properties which also covers the antioxidant performance. In order to evaluate the effects of lignin heterogeneity on its antioxidant activity, four lignin fractions from enzymatic hydrolysis lignin were classified by sequential organic solvent extraction and further evaluated by DPPH (1,1-Diphenyl-2-Picrylhydrazyl) free radical scavenging capacity and reducing power analysis. The characterization including FTIR,1H NMR and GPC showed that the fractionation process could effectively separate lignin fractions with distinctly different molecular weight and weaken the heterogeneity of unfractionated lignin. The antioxidant performance comparison of lignin fractions indicated that the dichloromethane fraction (F1) with lowest molecular weight (4585g/mol) and highest total phenolics content (246.13mg GAE/g) exhibited the highest antioxidant activity whose value was close to commercial antioxidant BHT (butylated hydroxytoluene). Moreover, the relationship between the antioxidant activity and the structure of lignin was further discussed to elucidate the mechanism of antioxidant activity improvement of lignin fractionation. Consequently, this study suggested that the sequential extraction was an effective way to obtain relatively homogeneous enzymatic hydrolysis lignin fractions which showed the potential for the value-added antioxidant application.
authors.affiliation: Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Liangliang
authors.initials: L
authors.lastname: An
authors.affiliation: Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education of China, Qilu University of Technology, Jinan 250353, China. Electronic address: ghwang@tust.edu.cn.
authors.forename: Guanhua
authors.initials: G
authors.lastname: Wang
authors.affiliation: School of Environmental Science and Engineering, Shandong Agriculture and Engineering College, Jinan 250100, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Jia
authors.affiliation: Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Cuiyun
authors.initials: C
authors.lastname: Liu
authors.affiliation: Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Sui
authors.affiliation: Tianjin Key Laboratory of Pulp and Paper, College of Paper Making Science and Technology, Tianjin University of Science and Technology, Tianjin 300457, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. Electronic address: sichli@tust.edu.cn.
authors.forename: Chuanling
authors.initials: C
authors.lastname: Si
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification*; D001713:Biphenyl Compounds / Q000737:chemistry; D005591:Chemical Fractionation / Q000379:methods*; D004798:Enzymes / Q000378:metabolism*; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry* / Q000302:isolation & purification*; D008970:Molecular Weight; D010636:Phenols / Q000032:analysis; D010851:Picrates / Q000737:chemistry; D013997:Time Factors; D003313:Zea mays / Q000737:chemistry
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D004798:Enzymes; D010636:Phenols; D010851:Picrates; D008031:Lignin; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Antioxidant activity; Characterization; Enzymatic hydrolysis lignin; Lignin fractionation; Sequential extraction