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The Enhancement Origin of Antioxidant Property of Carboxylated Lignin Isolated from Herbaceous Biomass Using the Maleic Acid Hydrotropic Fractionation

Overview
Journal Int J Mol Sci
Publisher MDPI
Date 2024 Sep 14
PMID 39273206
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Abstract

Lignin is endowed with antioxidant activity due to its diverse chemical structure. It is necessary to explore the relationship between antioxidant activity and the chemical structure of the lignin to develop its high-value utilization. Herein, we employed maleic acid (MA) as a hydrotropic agent to preferably isolate the lignin from distinct herbaceous sources (wheat straw and switchgrass) under atmospheric pressure conditions. The resultant acid hydrotropic lignin (AHL) isolated from wheat straw exhibited high radical scavenging rates, up to 98% toward DPPH and 94% toward ABTS. Further investigations indicated that during the MA hydrotropic fractionation (MAHF) process, lignin was carboxylated by MA at γ-OH of the side-chain, providing additional antioxidant activity from the carboxy group. It was also found that the radical scavenging rate of AHL has a positive correlation with carboxyl, phenolic hydroxyl contents, and the S-G (syringyl-guaiacyl) ratio, which could be realized by increasing the MAHF severity. Overall, this work underlies the enhancement origin of the antioxidant property of lignin, which will facilitate its application in biological fields as an efficient, cheap, and renewable antioxidant additive.

References
1.
Balakshin M, Capanema E, Gracz H, Chang H, Jameel H . Quantification of lignin-carbohydrate linkages with high-resolution NMR spectroscopy. Planta. 2011; 233(6):1097-110. DOI: 10.1007/s00425-011-1359-2. View

2.
Huang C, Wang X, Liang C, Jiang X, Yang G, Xu J . A sustainable process for procuring biologically active fractions of high-purity xylooligosaccharides and water-soluble lignin from bamboo prehydrolyzate. Biotechnol Biofuels. 2019; 12:189. PMC: 6661736. DOI: 10.1186/s13068-019-1527-3. View

3.
Zhu G, Ye D, Chen X, Wu Y, Yang Z, Mai Y . Lignin-derived polyphenols with enhanced antioxidant activities by chemical demethylation and their structure-activity relationship. Int J Biol Macromol. 2023; 237:124030. DOI: 10.1016/j.ijbiomac.2023.124030. View

4.
Du X, Perez-Boada M, Fernandez C, Rencoret J, Del Rio J, Jimenez-Barbero J . Analysis of lignin-carbohydrate and lignin-lignin linkages after hydrolase treatment of xylan-lignin, glucomannan-lignin and glucan-lignin complexes from spruce wood. Planta. 2014; 239(5):1079-90. DOI: 10.1007/s00425-014-2037-y. View

5.
Du X, Li J, Gellerstedt G, Rencoret J, Del Rio J, Martinez A . Understanding pulp delignification by laccase-mediator systems through isolation and characterization of lignin-carbohydrate complexes. Biomacromolecules. 2013; 14(9):3073-80. DOI: 10.1021/bm4006936. View