Title: | "Physicochemical Properties, Thermal Stability, and Pyrolysis Behavior of Antioxidative Lignin from Water Chestnut Shell Obtained with Ternary Deep Eutectic Solvents" |
Author(s): | Li F; Lv W; Huang D; Zeng C; Wang R; |
Address: | "Ethnic Medicinal Plant Resources Development Engineering Research Center of Guizhou, School of Chemistry and Chemical Engineering, Qiannan Normal University for Nationalities, Duyun 558000, China" |
DOI: | 10.3390/molecules28104088 |
ISSN/ISBN: | 1420-3049 (Electronic) 1420-3049 (Linking) |
Abstract: | "The molecular weight of lignin extracted from lignocellulosic biomass is an important factor in determining its valorization in industrial processes. Herein, this work aims to explore the extraction of high molecular weight and bioactive lignin from water chestnut shells under mild conditions. Five kinds of deep eutectic solvents were prepared and applied to isolate lignin from water chestnut shells. The extracted lignin was further characterized with element analysis, gel permeation chromatography, and Ultraviolet-visible and Fourier-transform infrared spectroscopy. The distribution of pyrolysis products was identified and quantified with thermogravimetric analysis-Fourier-transform infrared spectroscopy and pyrolysis-gas chromatograph-mass spectrometry. The results showed that choline chloride/ethylene glycol/p-toluenesulfonic acid (1:1.8:0.2 molar ratio) exhibited the highest fractionation efficiency for lignin (84.17% yield) at 100 degrees C for 2 h. Simultaneously, the lignin showed high purity (90.4%), high relative molecular weight (37,077 g/mol), and excellent uniformity. Furthermore, the aromatic ring structure of lignin remained intact, consisting mainly of p-hydroxyphenyl, syringl, and guaiacyl subunits. The lignin generated a large number of volatile organic compounds during the depolymerization process, mainly composed of ketones, phenols, syringols, guaiacols, esters, and aromatic compounds. Finally, the antioxidant activity of the lignin sample was evaluated with the 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay; the lignin from water chestnut shells showed excellent antioxidant activity. These findings confirm that lignin from water chestnut shells has a broad application prospect in valuable chemicals, biofuels and bio-functional materials" |
Keywords: | *Lignin/chemistry Antioxidants Deep Eutectic Solvents *Eleocharis Pyrolysis Solvents/chemistry Biomass antioxidant activity deep eutectic solvent lignin water chestnut shell; |
Notes: | "MedlineLi, Feng Lv, Wenzhi Huang, Dena Zeng, Chenglu Wang, Runping eng 21868029/National Nature Science Foundation of China/ ZK [2022]545/Natural Science Foundation of Guizhou Province/ [2018]079/Support Plan for Technology Top Talents in High Schools of Guizhou Province/ [2021]8/the Rolling Support Platform Project of Guizhou Provincial Education Department/ Switzerland 2023/05/27 Molecules. 2023 May 15; 28(10):4088. doi: 10.3390/molecules28104088" |