{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T17:32:15Z","timestamp":1791653535396,"version":"4.3.4"},"reference-count":44,"publisher":"American Chemical Society (ACS)","issue":"22","license":[{"start":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T00:00:00Z","timestamp":1653350400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["21776199"],"award-info":[{"award-number":["21776199"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22178017"],"award-info":[{"award-number":["22178017"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,6,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Lignin is a natural aromatic compound in plants. Several lignin structural models have been proposed in the past years, but all the models cannot be converted to benzene carboxylic acids (BCAs) for all aromatic rings connected to oxygen. This inspired us to explore the structures of lignin. Based on the yields of BCAs, the results of 13C NMR and ethanolysis residues, and gas chromatography\u2013mass spectrometry and electrospray ionization mass spectrometry of ethanolysis of lignin, we have constructed a structural model of lignin with a formula C6407H6736O2590N147S3. The model not only satisfies the results of analyses, but also explains the generation of BCAs from lignin oxidation and the ethanolysis products. Importantly, double-ring and triple-ring aromatic clusters are found in lignin, and some of them are connected by alkyl bridges, which results in conventional low conversions of lignin. Our findings in the structures of lignin may significantly influence the structures and applications of lignin.<\/jats:p>","DOI":"10.1021\/acsomega.2c01812","type":"journal-article","created":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T17:52:42Z","timestamp":1653414762000},"page":"18861-18869","source":"Crossref","is-referenced-by-count":13,"title":["A New Structural Model of Enzymatic Lignin with Multiring\nAromatic Clusters"],"prefix":"10.1021","volume":"7","author":[{"given":"Yupeng","family":"Wang","sequence":"first","affiliation":[{"name":"Beijing University of Chemical Technology , , ,","place":["Beijing, China, 100029"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9069-440X","authenticated-orcid":true,"given":"Yucui","family":"Hou","sequence":"additional","affiliation":[{"name":"Taiyuan Normal University , , , ,","place":["Jinzhong, Shanxi, China, 030619"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"He","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing University of Chemical Technology , , ,","place":["Beijing, China, 100029"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0843-3359","authenticated-orcid":true,"given":"Weize","family":"Wu","sequence":"additional","affiliation":[{"name":"Beijing University of Chemical Technology , , ,","place":["Beijing, China, 100029"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3253-8852","authenticated-orcid":true,"given":"Shuhang","family":"Ren","sequence":"additional","affiliation":[{"name":"Beijing University of Chemical Technology , , ,","place":["Beijing, China, 100029"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1722-1251","authenticated-orcid":true,"given":"Jianwei","family":"Li","sequence":"additional","affiliation":[{"name":"Beijing University of Chemical Technology , , ,","place":["Beijing, China, 100029"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2022,5,24]]},"reference":[{"key":"2026081710165716500_cit1","doi-asserted-by":"publisher","first-page":"484","DOI":"10.1126\/science.1114736","article-title":"The path forward\nfor biofuels and biomaterials","volume":"311","author":"Ragauskas","year":"2006","journal-title":"Science"},{"key":"2026081710165716500_cit2","doi-asserted-by":"publisher","first-page":"542","DOI":"10.1016\/j.biotechadv.2009.04.012","article-title":"Water-based woody biorefinery","volume":"27","author":"Amidon","year":"2009","journal-title":"Biotechnol.\nAdv."},{"key":"2026081710165716500_cit3","doi-asserted-by":"publisher","first-page":"384","DOI":"10.1039\/C3GC41631C","article-title":"Biomassfeedstocks\nfor renewable fuel production: A review of the impacts of feedstock\nand pretreatment on the yield and product distribution of fast pyrolysis\nbio-oils and vapors","volume":"16","author":"Carpenter","year":"2014","journal-title":"Green Chem."},{"key":"2026081710165716500_cit4","doi-asserted-by":"publisher","first-page":"2275","DOI":"10.1021\/acs.chemrev.5b00345","article-title":"Strategies for the conversion of lignin to high-value\npolymeric materials: Review and perspective","volume":"116","author":"Upton","year":"2015","journal-title":"Chem. Rev."},{"key":"2026081710165716500_cit5","doi-asserted-by":"publisher","first-page":"898","DOI":"10.1016\/j.trechm.2020.07.011","article-title":"Towards lignin-derived\nchemicals using atom-efficient\ncatalytic routes","volume":"2","author":"Sudarsanam","year":"2020","journal-title":"Trends Chem."},{"key":"2026081710165716500_cit6","doi-asserted-by":"publisher","first-page":"11559","DOI":"10.1021\/acs.chemrev.5b00155","article-title":"Catalytic\ntransformation of lignin for the production of chemicals and fuels","volume":"115","author":"Li","year":"2015","journal-title":"Chem. Rev."},{"key":"2026081710165716500_cit7","doi-asserted-by":"publisher","first-page":"12148","DOI":"10.1021\/acs.jafc.1c04416","article-title":"Polycyclic\naromatics observed in enzymatic lignin by spectral characterization\nand ruthenium ion-catalyzed oxidation","volume":"69","author":"Wang","year":"2021","journal-title":"J. Agr.\nFood Chem."},{"key":"2026081710165716500_cit8","doi-asserted-by":"publisher","DOI":"10.1016\/j.gee.2022.02.011","article-title":"Radical and (photo)\u00adelectron\ntransfer induced mechanisms\nfor lignin photo- and electro-catalytic depolymerization","author":"Wu","year":"2022","journal-title":"Green Energy Environ."},{"key":"2026081710165716500_cit9","doi-asserted-by":"publisher","first-page":"2651","DOI":"10.1039\/C5GC03043A","article-title":"New insights into the structure and\ncomposition of technical lignins: A comparative characterisation study","volume":"18","author":"Constant","year":"2016","journal-title":"Green Chem."},{"key":"2026081710165716500_cit10","doi-asserted-by":"publisher","DOI":"10.1016\/j.gee.2021.12.004","article-title":"Enhanced\nhydrodeoxygenation of lignin-derived anisole to arenes catalyzed by\nMn-doped Cu\/Al2O3","author":"Wang","year":"2022","journal-title":"Green Energy Environ."},{"key":"2026081710165716500_cit11","doi-asserted-by":"publisher","first-page":"285","DOI":"10.1021\/ef3016602","article-title":"Free-radical\nanalysis on thermochemical transformation of lignin to phenolic compounds","volume":"27","author":"Hu","year":"2012","journal-title":"Int. J. Remote Sens."},{"key":"2026081710165716500_cit12","doi-asserted-by":"publisher","first-page":"1152","DOI":"10.1038\/1831152a0","article-title":"Biosynthesis\nand constitution of lignin","volume":"183","author":"Freudenberg","year":"1959","journal-title":"Nature"},{"key":"2026081710165716500_cit13","doi-asserted-by":"publisher","first-page":"595","DOI":"10.1126\/science.148.3670.595","article-title":"Lignin: Its\nconstitution and formation from p-hydroxycinnamyl alcohols: Lignin\nis duplicated by dehydrogenation of these alcohols; intermediates\nexplain formation and structure","volume":"148","author":"Freudenberg","year":"1965","journal-title":"Science"},{"key":"2026081710165716500_cit14","doi-asserted-by":"publisher","first-page":"313","DOI":"10.1002\/anie.197403131","article-title":"Beech lignin\n\ue5f8 Proposal of a constitutional scheme","volume":"13","author":"Nimz","year":"1974","journal-title":"Angew. Chem., Int. 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Biotechnol."},{"key":"2026081710165716500_cit19","doi-asserted-by":"publisher","first-page":"4385","DOI":"10.1002\/cssc.202001324","article-title":"Lignin source\nand structural characterization","volume":"13","author":"Sun","year":"2020","journal-title":"ChemSusChem"},{"key":"2026081710165716500_cit20","first-page":"146","volume-title":"Cross polarization\/magic\nangle spinning nuclear magnetic resonance (CP\/MAS NMR) spectroscopy","author":"Leary","year":"1992"},{"key":"2026081710165716500_cit21","doi-asserted-by":"publisher","first-page":"4006","DOI":"10.1021\/ef200738p","article-title":"Evaluation of structural characteristics\nof Huadian oil shale kerogen using direct techniques (solid-state 13C NMR, XPS, FT-IR, and XRD)","volume":"25","author":"Tong","year":"2011","journal-title":"Energy\nFuels"},{"key":"2026081710165716500_cit22","doi-asserted-by":"publisher","first-page":"176","DOI":"10.1016\/j.fuel.2015.02.117","article-title":"Insight into the structural features\nof Zhaotong lignite using multiple techniques","volume":"153","author":"Li","year":"2015","journal-title":"Fuel"},{"key":"2026081710165716500_cit23","doi-asserted-by":"publisher","first-page":"347","DOI":"10.1038\/s41467-018-08252-0","article-title":"Lignin-polysaccharide interactions\nin plant secondary cell walls revealed by solid-state NMR","volume":"10","author":"Kang","year":"2019","journal-title":"Nat. Commun."},{"key":"2026081710165716500_cit24","doi-asserted-by":"publisher","first-page":"39","DOI":"10.1016\/j.fuel.2014.10.039","article-title":"Rapid and\naccurate determination\nof the lignin content of lignocellulosic biomass by solid-state NMR","volume":"141","author":"Fu","year":"2015","journal-title":"Fuel"},{"key":"2026081710165716500_cit25","doi-asserted-by":"publisher","first-page":"9677","DOI":"10.1021\/jf062199q","article-title":"Differences\nbetween lignin in unprocessed wood, milled Wood, mutant wood, and\nextracted lignin detected by 13C solid-state NMR","volume":"54","author":"Mao","year":"2006","journal-title":"J. Agr. Food Chem."},{"key":"2026081710165716500_cit26","doi-asserted-by":"publisher","first-page":"302","DOI":"10.1515\/hfsg.1993.47.4.302","article-title":"A comparison\nof solution and solid state 13C NMR spectra of lignins\nand lignin model compounds","volume":"47","author":"Hawkes","year":"1993","journal-title":"Holzforschung"},{"key":"2026081710165716500_cit27","doi-asserted-by":"publisher","first-page":"863","DOI":"10.1016\/S0031-9422(97)00359-2","article-title":"Solid state\nNMR spectroscopy of specifically 13C-enriched lignin in\nwheat straw from coniferin","volume":"46","author":"Terashima","year":"1997","journal-title":"Phytochemistry"},{"key":"2026081710165716500_cit28","doi-asserted-by":"publisher","first-page":"137","DOI":"10.1080\/02773813.2017.1393436","article-title":"Solid-state 13C CP\/MAS\nNMR for alkyl-o-aryl\nbond determination in lignin preparations","volume":"38","author":"Evstigneyev","year":"2018","journal-title":"J.\nWood Chem.Technol."},{"key":"2026081710165716500_cit29","doi-asserted-by":"publisher","first-page":"1083","DOI":"10.1515\/hf-2019-0011","article-title":"Evaluation\nof ring-5 structures of guaiacyl lignin in ginkgo biloba L. Using\nsolid- and liquid-state 13C NMR difference spectroscopy","volume":"73","author":"Aoki","year":"2019","journal-title":"Holzforschung"},{"key":"2026081710165716500_cit30","doi-asserted-by":"publisher","first-page":"7456","DOI":"10.1021\/jacs.5b03693","article-title":"Aromatic monomers by in situ conversion of reactive intermediates\nin the acid-catalyzed depolymerization of lignin","volume":"137","author":"Deuss","year":"2015","journal-title":"J. Am. Chem. Soc."},{"key":"2026081710165716500_cit31","doi-asserted-by":"publisher","first-page":"626","DOI":"10.1002\/cssc.200800080","article-title":"Selective degradation\nof wood lignin over noble-metal catalysts in\na two-step process","volume":"1","author":"Yan","year":"2008","journal-title":"ChemSusChem"},{"key":"2026081710165716500_cit32","doi-asserted-by":"publisher","first-page":"848","DOI":"10.1021\/ef0502397","article-title":"Pyrolysis of wood\/biomass\nfor bio-oil: A critical review","volume":"20","author":"Mohan","year":"2006","journal-title":"Energy Fuels"},{"key":"2026081710165716500_cit33","doi-asserted-by":"publisher","first-page":"4941","DOI":"10.1039\/C5GC01120E","article-title":"Ethanol as capping\nagent and formaldehyde scavenger for efficient depolymerization of\nlignin to aromatics","volume":"17","author":"Huang","year":"2015","journal-title":"Green Chem."},{"key":"2026081710165716500_cit34","doi-asserted-by":"publisher","first-page":"6212","DOI":"10.1039\/D0SE01016B","article-title":"Mild\nthermolytic solvolysis of technical lignins in polar organic solvents\nto a crude lignin oil","volume":"4","author":"Kouris","year":"2020","journal-title":"Sustainable Energy Fuels"},{"key":"2026081710165716500_cit35","doi-asserted-by":"publisher","first-page":"5596","DOI":"10.1021\/ef501414g","article-title":"Characterization of oxygen-containing species in methanolysis\nproducts of the extraction residue from Xianfeng lignite with negative-ion\nelectrospray ionization fourier transform ion cyclotron resonance\nmass spectrometry","volume":"28","author":"Liu","year":"2014","journal-title":"Energy Fuels"},{"key":"2026081710165716500_cit36","doi-asserted-by":"publisher","first-page":"339","DOI":"10.1002\/mabi.200350006","article-title":"Application of electrospray ionization mass spectrometry\nto the elucidation of the primary structure of lignin","volume":"3","author":"Evtuguin","year":"2003","journal-title":"Macromol. Biosci."},{"key":"2026081710165716500_cit37","doi-asserted-by":"publisher","first-page":"525","DOI":"10.1515\/HF.1999.086","article-title":"Electrospray\nionization mass spectrometry as a tool\nfor lignins molecular weight and structural characterisation","volume":"53","author":"Evtuguin","year":"1999","journal-title":"Holzforschung"},{"key":"2026081710165716500_cit38","doi-asserted-by":"publisher","first-page":"3677","DOI":"10.1039\/C5NJ02916C","article-title":"Thermochemical lignin depolymerization\nand conversion to aromatics in subcritical methanol: Effects of catalytic\nconditions","volume":"40","author":"Singh","year":"2016","journal-title":"New J. Chem."},{"key":"2026081710165716500_cit39","doi-asserted-by":"publisher","first-page":"994","DOI":"10.1039\/c2ee23741e","article-title":"Lignin depolymerization (LDP) in alcohol over nickel-based\ncatalysts via a fragmentation\u2013hydrogenolysis process","volume":"6","author":"Song","year":"2013","journal-title":"Energy Environ. Sci."},{"key":"2026081710165716500_cit40","doi-asserted-by":"publisher","first-page":"595","DOI":"10.1021\/ef502373p","article-title":"Structural\ncharacterization of typical organic species in Jincheng No. 15 anthracite","volume":"29","author":"Wang","year":"2015","journal-title":"Energy Fuels"},{"key":"2026081710165716500_cit41","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1116\/1.4943099","article-title":"Characterisation of cellulose and\nhardwood organosolv lignin reference materials by XPS","volume":"23","author":"Ban\u0303uls-Ciscar","year":"2016","journal-title":"Surf. Sci. Spectra"},{"key":"2026081710165716500_cit42","doi-asserted-by":"publisher","first-page":"284","DOI":"10.1002\/sia.1301","article-title":"XPS study of living\ntree","volume":"34","author":"Shchukarev","year":"2002","journal-title":"Surf. Interface Anal."},{"key":"2026081710165716500_cit43","first-page":"1073","article-title":"Analysis of\nthe nutritional components of corn cobs","volume":"28","author":"Chen","year":"2012","journal-title":"Modern\nFood Sci. Technol."},{"key":"2026081710165716500_cit44","first-page":"134","article-title":"Determination\nof o-containing functional groups distribution in low-rank coals by\nchemical titration","volume":"41","author":"Zhou","year":"2013","journal-title":"J. Fuel Chem. Technol."}],"container-title":["ACS Omega"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/acsomega.2c01812","content-type":"application\/pdf","content-version":"vor","intended-application":"unspecified"},{"URL":"https:\/\/pubs.acs.org\/acsodf\/article-pdf\/7\/22\/18861\/4224518\/ao2c01812.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.acs.org\/acsodf\/article-pdf\/7\/22\/18861\/4224518\/ao2c01812.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T15:05:36Z","timestamp":1786979136000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/acsodf\/article\/7\/22\/18861\/418133\/A-New-Structural-Model-of-Enzymatic-Lignin-with"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,5,24]]},"references-count":44,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,5,24]]},"published-print":{"date-parts":[[2022,6,7]]}},"URL":"https:\/\/doi.org\/10.1021\/acsomega.2c01812","relation":{},"ISSN":["2470-1343"],"issn-type":[{"value":"2470-1343","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,5,24]]}}}