{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T09:33:57Z","timestamp":1793007237722,"version":"4.5.0"},"reference-count":45,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T00:00:00Z","timestamp":1792713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T00:00:00Z","timestamp":1792713600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001807","name":"S\u00e3o Paulo Research Foundation","doi-asserted-by":"publisher","award":["2023\/07568-4"],"award-info":[{"award-number":["2023\/07568-4"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2023\/07568-4"],"award-info":[{"award-number":["2023\/07568-4"]}],"id":[{"id":"https:\/\/ror.org\/02ddkpn78","id-type":"ROR","asserted-by":"publisher"}]},{"name":"National Institute of Science and Technology on Bioanalytics-Lauro Kubota","award":["408338\/2024-5"],"award-info":[{"award-number":["408338\/2024-5"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Reliable determination of cellulose crystallinity is essential for biomass valorization, yet commonly used analytical methods may respond differently to residual non-cellulosic components present in partially purified lignocellulosic materials. In this study, fourteen cellulose-rich samples were produced from depectinated orange biomass under controlled alkaline processing conditions and characterized by Fourier-transform infrared spectroscopy (FT-IR), solid-state 13C nuclear magnetic resonance (CP\/MAS 13C NMR), and X-ray diffraction (XRD). Crystallinity indices (CIs) were calculated using the lateral order index (FT-IR), C4 peak deconvolution (ssNMR), and the Segal method (XRD), while principal component analysis was employed to support multivariate interpretation of the FT-IR and NMR datasets. FT-IR-derived CIs ranged from approximately 65 to 91%, with the starting biomass exhibiting the highest value despite its substantial residual pectin content. In contrast, ssNMR-derived CIs were consistently lower (approximately 27\u201349%) and showed limited sensitivity to residual pectin, indicating greater selectivity toward cellulose crystalline organization. XRD produced intermediate CI values and displayed a moderate positive correlation with ssNMR (r = 0.5) but a moderate negative correlation with FT-IR (r = \u22120.5). PCA further revealed that pectin-associated FT-IR bands (~1737 and ~1635 cm\u22121) were the primary drivers separating the starting biomass from the purified cellulose samples. The study establishes a practical framework for selecting crystallinity evaluation methods during the sustainable valorization of citrus biomass into cellulose-based materials.<\/jats:p>","DOI":"10.3390\/molecules31213833","type":"journal-article","created":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T08:40:18Z","timestamp":1793004018000},"page":"3833","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Cellulose Crystallinity in Orange Biomass-Derived Cellulose: Comparative Assessment by FT-IR, Solid-State 13C NMR, and X-Ray Diffraction"],"prefix":"10.3390","volume":"31","author":[{"given":"Symone","family":"Costa de Castro","sequence":"first","affiliation":[{"name":"Laboratory of Biological Chemistry (LQB), Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-970, SP, Brazil"},{"name":"Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia Farroupilha (IFFar), Alegrete 97555-000, RS, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Matheus","family":"Signorelli Corr\u00eaa","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry (LQB), Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-970, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2930-7332","authenticated-orcid":false,"given":"Ljubica","family":"Tasic","sequence":"additional","affiliation":[{"name":"Laboratory of Biological Chemistry (LQB), Institute of Chemistry, Universidade Estadual de Campinas (UNICAMP), Campinas 13083-970, SP, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Freitas, C.M., Coimbra, J.S.R., Souza, V.G.L., and Sousa, R.C.S. (2021). Structure and applications of pectin in food, biomedical, and pharmaceutical industry: A review. Coatings, 11.","DOI":"10.3390\/coatings11080922"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"110675","DOI":"10.1016\/j.foodhyd.2024.110675","article-title":"Citrus flavonoid-pectin conjugates with enhanced emulsifying properties","volume":"159","author":"Liu","year":"2025","journal-title":"Food Hydrocoll."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"368","DOI":"10.1002\/bbb.1551","article-title":"Pectin: A new perspective from the biorefinery standpoint","volume":"9","author":"Ciriminna","year":"2015","journal-title":"Biofuels Bioprod. Biorefin."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"804","DOI":"10.1002\/bbb.2606","article-title":"Sequential extraction of hesperidin, pectin, lignin, and cellulose from orange peels: Towards valorization of agro-waste","volume":"18","author":"Castro","year":"2024","journal-title":"Biofuels Bioprod. Biorefin."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.wasman.2018.07.028","article-title":"High value-added products from the orange juice industry waste","volume":"111","author":"Cypriano","year":"2018","journal-title":"Waste Manag."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"5908","DOI":"10.3390\/molecules20045908","article-title":"Enhanced materials from nature: Nanocellulose from citrus waste","volume":"20","author":"Tasic","year":"2015","journal-title":"Molecules"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1007\/s10965-024-03946-0","article-title":"Synthesis and suitability characterization of microcrystalline cellulose from Citrus x sinensis sweet orange peel fruit waste-based biomass for polymer composite applications","volume":"31","author":"Palaniappan","year":"2024","journal-title":"J. Polym. Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"6417","DOI":"10.1039\/D2CS00569G","article-title":"Comparison and assessment of methods for cellulose crystallinity determination","volume":"52","author":"Salem","year":"2023","journal-title":"Chem. Soc. Rev."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1007\/s10570-009-9378-x","article-title":"Attenuated total reflectance Fourier-transform Infrared spectroscopy analysis of crystallinity changes in lyocell following continuous treatment with sodium hydroxide","volume":"17","author":"Blackburn","year":"2010","journal-title":"Cellulose"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1073","DOI":"10.1007\/s10570-016-0881-6","article-title":"Comparison of sample crystallinity determination methods by X-ray diffraction for challenging cellulose I materials","volume":"23","author":"Ahvenainen","year":"2016","journal-title":"Cellulose"},{"key":"ref_11","first-page":"1491","article-title":"Determination of Cellulose Crystallinity of Banana Residues Using Near Infrared","volume":"26","author":"Rambo","year":"2015","journal-title":"J. Braz. Chem. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"583","DOI":"10.1007\/s10570-012-9833-y","article-title":"Cellulose polymorphy, crystallite size, and the Segal crystallinity index","volume":"20","author":"French","year":"2013","journal-title":"Cellulose"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1571","DOI":"10.1111\/j.1742-4658.2010.07585.x","article-title":"Cellulose crystallinity\u2014A key predictor of the enzymatic hydrolysis rate","volume":"277","author":"Hall","year":"2010","journal-title":"FEBS J."},{"key":"ref_14","first-page":"3993","article-title":"Relationship between crystallinity index and enzymatic hydrolysis performance of celluloses separated from aquatic and terrestrial plant materials","volume":"9","author":"Li","year":"2014","journal-title":"BioResources"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1016\/j.carbpol.2018.03.003","article-title":"New cellulose crystallinity estimation method that differentiates between organized and crystalline phases","volume":"190","author":"Agarwal","year":"2018","journal-title":"Carbohydr. Polym."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1186\/s13068-015-0292-1","article-title":"Quantitative 13C multiCP solid-state NMR as a tool for evaluation of cellulose crystallinity index measured directly inside sugarcane biomass","volume":"8","author":"Bernardinelli","year":"2015","journal-title":"Biotechnol. Biofuels"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Stanciu, M., Tanas\u00e3, F., and Teac\u00e3, C. (2025). Crystallinity Changes in Modified Cellulose Substrates Evidenced by Spectral and X-Ray Diffraction Data. Polysaccharides, 6.","DOI":"10.3390\/polysaccharides6020030"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2377","DOI":"10.1007\/s13399-020-00766-2","article-title":"Structural changes of waste biomass induced by alkaline treatment: The effect on crystallinity and thermal properties","volume":"12","author":"Petrovic","year":"2022","journal-title":"Biomass Convers. Biorefin."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5445","DOI":"10.1007\/s10570-020-03172-z","article-title":"Increment in evolution of cellulose crystallinity analysis","volume":"27","author":"French","year":"2020","journal-title":"Cellulose"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"641","DOI":"10.1007\/s10570-009-9321-1","article-title":"Measuring the crystallinity index of cellulose by solid state 13C nuclear magnetic resonance","volume":"16","author":"Park","year":"2009","journal-title":"Cellulose"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5563","DOI":"10.1007\/s10570-020-03177-8","article-title":"Improved cellulose X-ray diffraction analysis using Fourier series modeling","volume":"27","author":"Yao","year":"2020","journal-title":"Cellulose"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"122593","DOI":"10.1016\/j.carbpol.2024.122593","article-title":"Study of the effect of bleaching agents on the crystalline index of cellulose-based materials derived from corn husk by CP\/MAS 13C NMR and FT-IR spectroscopies","volume":"346","author":"Mayta","year":"2024","journal-title":"Carbohydr. Polym."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Nokab, M.E.H.E., Habib, M.H., Alassmy, Y.A., Abduljawad, M.M., Alshamrani, K.M., and Sebakhy, K.O. (2022). Solid state NMR a powerful technique for investigating sustainable\/renewable cellulose-based materials. Polymers, 14.","DOI":"10.3390\/polym14051049"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"47223","DOI":"10.1021\/jacs.5c14452","article-title":"Using solid-state NMR to understand the structure of plant cellulose","volume":"147","author":"Cresswell","year":"2025","journal-title":"J. Am. Chem. Soc."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"5739","DOI":"10.1007\/s10570-018-1977-y","article-title":"A multistep mild process for preparation of nanocellulose from orange bagasse","volume":"25","author":"Rezende","year":"2018","journal-title":"Cellulose"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"717","DOI":"10.1016\/j.ijbiomac.2018.01.098","article-title":"Isolation and characterization of microcrystalline cellulose from pomelo peel","volume":"111","author":"Liu","year":"2018","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"115732","DOI":"10.1016\/j.mtcomm.2026.115732","article-title":"Influence of sequential alkaline\u2013acid\u2013peroxide fractionation on the structural integrity and thermal stability of sugarcane bagasse cellulose","volume":"54","author":"Terefe","year":"2026","journal-title":"Mater. Today Commun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"9963","DOI":"10.1007\/s10668-021-01852-9","article-title":"Comparative evaluation of cellulose nanocrystals from bagasse and coir agro-wastes for reinforcing PVA-based composites","volume":"24","author":"Pavalaydon","year":"2022","journal-title":"Environ. Dev. Sustain."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2638621","DOI":"10.1080\/19476337.2026.2638621","article-title":"Development and characterization of sustainable cellulose nanofibers from passion fruit peel using citric and hydrochloric acids","volume":"24","author":"Llacza","year":"2026","journal-title":"CyTA-J. Food"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1016\/j.foodchem.2014.12.033","article-title":"FT-IR spectroscopy, a reliable method for routine analysis of the degree of methylesterification of pectin in different fruit- and vegetable-based matrices","volume":"176","author":"Kyomugasho","year":"2015","journal-title":"Food Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"727","DOI":"10.15376\/biores.5.2.727-740","article-title":"Luffa cylindrica as a lignocellulosic source of fiber, microfibrillated cellulose, and cellulose nanocrystals","volume":"5","author":"Siqueira","year":"2010","journal-title":"BioResources"},{"key":"ref_32","first-page":"878","article-title":"Agroindustry residues as a source for cellulose nanofibers production","volume":"32","author":"Cypriano","year":"2021","journal-title":"J. Braz. Chem. Soc."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Mansor, M.H., Williamson, L., Ludwikowski, D., Howard, F., and Muthana, M. (2025). Pectin extraction from citrus waste: Structural quality and yield with mineral and organic acids. Physchem, 5.","DOI":"10.3390\/physchem5030032"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"100168","DOI":"10.1016\/j.fochx.2021.100168","article-title":"Applications of infrared spectroscopy in polysaccharide structural analysis: Progress, challenge and perspective","volume":"12","author":"Hong","year":"2021","journal-title":"Food Chem. X"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"9967","DOI":"10.1007\/s13399-022-03085-w","article-title":"Treating lignocellulosic biomass with dilute solutions at ambient temperature: Effects on cellulose crystallinity","volume":"14","author":"Yaman","year":"2024","journal-title":"Biomass Convers. Biorefin."},{"key":"ref_36","first-page":"5","article-title":"X-ray diffraction study of pine wood treated with NaOH","volume":"13","author":"Borysiak","year":"2005","journal-title":"Fibres Text. East. Eur."},{"key":"ref_37","first-page":"45","article-title":"Hydrothermal alkaline treatment of lignocellulosic biomass for microcrystalline cellulose generation at subcritical water","volume":"51","author":"Machmudah","year":"2025","journal-title":"S. Afr. J. Chem. Eng."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1953","DOI":"10.1111\/ijfs.12862","article-title":"Renewable cellulose source: Isolation and characterisation of cellulose from rice stubble residues","volume":"50","author":"Rodsamran","year":"2015","journal-title":"Int. J. Food Sci. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1016\/j.biortech.2013.10.009","article-title":"Understanding changes in cellulose crystalline structure of lignocellulosic biomass during ionic liquid pretreatment by XRD","volume":"151","author":"Zhang","year":"2014","journal-title":"Bioresour. Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1016\/j.carbpol.2019.03.103","article-title":"Optimum alkaline treatment parameters for the extraction of cellulose and production of cellulose nanocrystals from apple pomace","volume":"215","author":"Bilek","year":"2019","journal-title":"Carbohydr. Polym."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1186\/1754-6834-3-10","article-title":"Cellulose crystallinity index: Measurement techniques and their impact on interpreting cellulase performance","volume":"3","author":"Park","year":"2010","journal-title":"Biotechnol. Biofuels"},{"key":"ref_42","unstructured":"ANKOM Technology (2022, July 01). ANKOM 2000 Fiber Analyzer. Available online: https:\/\/www.ankom.com\/product-catalog\/ankom-2000-fiber-analyzer?srsltid=AfmBOopssSEonuP4WkQAx5PAPvTc3jwlGzz9HMYLXPRubNVDIYOD-LSy."},{"key":"ref_43","unstructured":"Sluiter, A., Hames, B., Ruiz, R., Scarlata, C., Sluiter, J., Templeton, D., and Crocker, D. (2024, February 15). Determination of Structural Carbohydrates and Lignin in Biomass. Laboratory Analytical Procedure (LAP). National Renewable Energy Laboratory, Available online: https:\/\/docs.nlr.gov\/docs\/gen\/fy13\/42618.pdf."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Zhao, M., Kuang, F., Zhang, Y., and Lv, G. (2024). Effects of hydrolysis condition and detection method on the monosaccharide composition analysis of polysaccharides from natural sources. Separations, 11.","DOI":"10.2139\/ssrn.4579545"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.colsurfb.2013.02.016","article-title":"Extraction and characterization of microcrystalline cellulose from fodder grass; Setaria glauca (L) P. Beauv, and its potential as a drug delivery vehicle for isoniazid, a first line antituberculosis drug","volume":"108","author":"Kalita","year":"2013","journal-title":"Colloids Surf. B Biointerfaces"}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/21\/3833\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T08:43:40Z","timestamp":1793004220000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/31\/21\/3833"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,23]]},"references-count":45,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2026,11]]}},"alternative-id":["molecules31213833"],"URL":"https:\/\/doi.org\/10.3390\/molecules31213833","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,23]]}}}