{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,23]],"date-time":"2025-10-23T05:38:28Z","timestamp":1761197908761,"version":"build-2065373602"},"reference-count":53,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T00:00:00Z","timestamp":1610668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["PID2019-110031RB-I00"],"award-info":[{"award-number":["PID2019-110031RB-I00"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Conseller\u00eda de Cultura, Educaci\u00f3n e Ordenaci\u00f3n Universitaria","award":["ED431C 2017\/62-GRC"],"award-info":[{"award-number":["ED431C 2017\/62-GRC"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Agronomy"],"abstract":"<jats:p>In this work, a delignification process, using lime (Ca(OH)2) as an alternative alkali, was evaluated to improve enzymatic saccharification of corn stover cellulose, with the final goal of obtaining second-generation bioethanol. For that, an experimental design was conducted in order to assay the effect of temperature, lime loading, and time on the corn stover fractionation and enzymatic susceptibility of cellulose. Under conditions evaluated, lime pretreatment was selective for the recovery of cellulose (average of 91%) and xylan (average of 75.3%) in the solid phase. In addition, operating in mild conditions, a delignification up to 40% was also attained. On the other hand, a maximal cellulose-to-glucose conversion (CGCMAX) of 89.5% was achieved using the solid, resulting from the treatment carried out at 90 \u00b0C for 5 h and lime loading of 0.4 g of Ca(OH)2\/g of corn stover. Finally, under selected conditions of pretreatment, 28.7 g\/L (or 3.6% v\/v) of bioethanol was produced (corresponding to 72.4% of ethanol conversion) by simultaneous saccharification and fermentation. Hence, the process, based on an alternative alkali proposed in this work, allowed the successful production of biofuel from the important and abundant agro-industrial residue of corn stover.<\/jats:p>","DOI":"10.3390\/agronomy11010155","type":"journal-article","created":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T12:44:05Z","timestamp":1610714645000},"page":"155","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Alternative Lime Pretreatment of Corn Stover for Second-Generation Bioethanol Production"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2529-1348","authenticated-orcid":false,"given":"Iria","family":"F\u00edrvida","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7156-8961","authenticated-orcid":false,"given":"Pablo G.","family":"del R\u00edo","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2379-7249","authenticated-orcid":false,"given":"Patricia","family":"Gull\u00f3n","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]},{"given":"Beatriz","family":"Gull\u00f3n","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]},{"given":"Gil","family":"Garrote","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]},{"given":"Aloia","family":"Roman\u00ed","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Faculty of Science, Campus Ourense, Universidade de Vigo, As Lagoas, 32004 Ourense, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"123722","DOI":"10.1016\/j.biortech.2020.123722","article-title":"Comparative study of biorefinery processes for the valorization of fast-growing Paulownia wood","volume":"314","author":"Garrote","year":"2020","journal-title":"Bioresour. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Dom\u00ednguez, E., del R\u00edo, P.G., Roman\u00ed, A., Garrote, G., Gull\u00f3n, P., and de Vega, A. (2020). Formosolv pretreatment to fractionate paulownia wood following a biorefinery approach: Isolation and characterization of the lignin fraction. Agronomy, 10.","DOI":"10.3390\/agronomy10081205"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Del Razola-D\u00edaz, M.C., Verardo, V., Mart\u00edn-Garc\u00eda, B., D\u00edaz-De-Cerio, E., Garc\u00eda-Villanova, B., and Guerra-Hern\u00e1ndez, E.J. (2020). Establishment of acid hydrolysis by box-behnken methodology as pretreatment to obtain reducing sugars from tiger nut byproducts. Agronomy, 10.","DOI":"10.3390\/agronomy10040477"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"S\u00e1nchez-Guti\u00e9rrez, M., Espinosa, E., Basc\u00f3n-Villegas, I., P\u00e9rez-Rodr\u00edguez, F., Carrasco, E., and Rodr\u00edguez, A. (2020). Production of cellulose nanofibers from olive tree harvest\u2013A residue with wide applications. Agronomy, 10.","DOI":"10.3390\/agronomy10050696"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Von Cossel, M., Wagner, M., Lask, J., Magenau, E., Bauerle, A., Von Cossel, V., Warrach-Sagi, K., Elbersen, B., Staritsky, I., and van Eupen, M. (2019). Prospects of Bioenergy Cropping Systems for a More Social-Ecologically Sound Bioeconomy. Agronomy, 9.","DOI":"10.3390\/agronomy9100605"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1016\/j.indcrop.2018.12.051","article-title":"Energy recovery from industrial crop wastes by dry anaerobic digestion: A review","volume":"129","author":"Momayez","year":"2019","journal-title":"Ind. Crops Prod."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"877","DOI":"10.1016\/j.rser.2018.03.111","article-title":"Pretreatment of lignocellulosic wastes for biofuel production: A critical review","volume":"90","author":"Kumari","year":"2018","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"174","DOI":"10.17113\/ftb.56.02.18.5428","article-title":"Review of Second Generation Bioethanol Production from Residual Biomass","volume":"56","author":"Robak","year":"2018","journal-title":"Food Technol. Biotechnol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.renene.2009.02.025","article-title":"Land use competition for production of food and liquid biofuels: An analysis of the arguments in the current debate","volume":"35","author":"Rathmann","year":"2010","journal-title":"Renew. Energy"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"9200","DOI":"10.1002\/anie.200801476","article-title":"Biofuels and biomass-to-liquid fuels in the biorefinery: Catalytic conversion of lignocellulosic biomass using porous materials","volume":"47","year":"2008","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1016\/j.rser.2009.10.003","article-title":"Production of first and second generation biofuels: A comprehensive review","volume":"14","author":"Naik","year":"2010","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Krafft, M.J., Bendler, M., Schreiber, A., and Saake, B. (2020). Steam refining with subsequent alkaline lignin extraction as an alternative pretreatment method to enhance the enzymatic digestibility of corn stover. Agronomy, 10.","DOI":"10.3390\/agronomy10060811"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Mafa, M.S., Malgas, S., Bhattacharya, A., and Rashamuse, K. (2020). The effects of alkaline pretreatment on agricultural biomasses (corn cob and sweet sorghum bagasse) and their hydrolysis by a termite-derived enzyme cocktail. Agronomy, 10.","DOI":"10.3390\/agronomy10081211"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Mkabayi, L., Malgas, S., Wilhelmi, B.S., and Pletscheke, B.I. (2020). Evaluating feruloyl esterase\u2014Xylanase synergism for hydroxycinnamic zcid and xylo-oligosaccharide production from untreated, hydrothermally pre-treated and dilute-acid pre-treated corn cobs. Agronomy, 10.","DOI":"10.3390\/agronomy10050688"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1182","DOI":"10.1039\/b926617h","article-title":"Switchgrass as an energy crop for biofuel production: A review of its ligno-cellulosic chemical properties","volume":"3","author":"David","year":"2010","journal-title":"Energy Environ. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1002\/bbb.134","article-title":"The role of biomass in America\u2019s energy future: Framing the analysis","volume":"3","author":"Lynd","year":"2009","journal-title":"Biofuels Bioprod. Biorefin."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Jenkins, B.M. (2014). Global Agriculture: Industrial Feedstocks for Energy and Materials, Elsevier Ltd.","DOI":"10.1016\/B978-0-444-52512-3.00156-X"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Tandzi, L.N., and Mutengwa, C.S. (2020). Estimation of maize (Zea mays L.) yield per harvest area: Appropriate methods. Agronomy, 10.","DOI":"10.3390\/agronomy10010029"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"L\u00f3pez-Malvar, A., Djemel, A., Santiago, R., and Revilla, P. (2020). Assessment of Algerian maize populations for saccharification and nutritive value. Agronomy, 10.","DOI":"10.3390\/agronomy10050646"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1016\/j.pecs.2018.03.004","article-title":"Bioethanol from corn stover\u2013A review and technical assessment of alternative biotechnologies","volume":"67","author":"Zhao","year":"2018","journal-title":"Prog. Energy Combust. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"113104","DOI":"10.1016\/j.enconman.2020.113104","article-title":"Bioethanol production from water-soluble and structural carbohydrates of normal and high sugary corn stovers harvested at three growth stages","volume":"221","author":"Akter","year":"2020","journal-title":"Energy Convers. Manag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"112344","DOI":"10.1016\/j.enconman.2019.112344","article-title":"Temperature profiled simultaneous saccharification and co-fermentation of corn stover increases ethanol production at high solid loading","volume":"205","author":"Zhu","year":"2020","journal-title":"Energy Convers. Manag."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"del R\u00edo, P.G., Gull\u00f3n, P., Rebelo, F.R., Roman\u00ed, A., Garrote, G., and Gull\u00f3n, B. (2020). A whole-slurry fermentation approach to high-solid loading for bioethanol production from corn stover. Agronomy, 10.","DOI":"10.3390\/agronomy10111790"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"113517","DOI":"10.1016\/j.enconman.2020.113517","article-title":"Sequential two-stage autohydrolysis biorefinery for the production of bioethanol from fast-growing Paulownia biomass","volume":"226","author":"Garrote","year":"2020","journal-title":"Energy Convers. Manag."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"123789","DOI":"10.1016\/j.biortech.2020.123789","article-title":"Alkaline sulfonation and thermomechanical pulping pretreatment of softwood chips and pellets to enhance enzymatic hydrolysis","volume":"315","author":"Wu","year":"2020","journal-title":"Bioresour. Technol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1002\/bbb.49","article-title":"Pretreatment: The key to unloking low-cost cellulosic ethanol","volume":"2","author":"Yang","year":"2008","journal-title":"Biofuels Bioprod. Biorefin."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1016\/j.biortech.2004.06.025","article-title":"Features of promising technologies for pretreatment of lignocellulosic biomass","volume":"96","author":"Mosier","year":"2005","journal-title":"Bioresour. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"743","DOI":"10.1007\/s10570-009-9309-x","article-title":"Role of pretreatment and conditioning processes on toxicity of lignocellulosic biomass hydrolysates","volume":"16","author":"Pienkos","year":"2009","journal-title":"Cellulose"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1768","DOI":"10.1007\/s12010-010-8958-4","article-title":"Evaluation of high solids alkaline pretreatment of rice straw","volume":"162","author":"Cheng","year":"2010","journal-title":"Appl. Biochem. Biotechnol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1016\/j.biortech.2016.08.077","article-title":"Combined alkali and hydrothermal pretreatments for oat straw valorization within a biorefinery concept","volume":"220","author":"Tomaz","year":"2016","journal-title":"Bioresour. Technol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1696","DOI":"10.1007\/s12010-013-0097-2","article-title":"Lime pretreatment and fermentation of enzymatically hydrolyzed sugarcane bagasse","volume":"169","author":"Rabelo","year":"2013","journal-title":"Appl. Biochem. Biotechnol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"971","DOI":"10.1016\/j.biombioe.2008.01.014","article-title":"Lime pretreatment, enzymatic saccharification and fermentation of rice hulls to ethanol","volume":"32","author":"Saha","year":"2008","journal-title":"Biomass Bioenergy"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"6805","DOI":"10.1016\/j.biortech.2010.03.098","article-title":"A novel lime pretreatment for subsequent bioethanol production from rice straw\u2013Calcium capturing by carbonation (CaCCO) process","volume":"101","author":"Park","year":"2010","journal-title":"Bioresour. Technol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1830","DOI":"10.1021\/ef2000932","article-title":"Lime pretreatment of coastal bermudagrass for bioethanol production","volume":"25","author":"Wang","year":"2011","journal-title":"Energy Fuels"},{"key":"ref_35","unstructured":"Sluiter, A., Hames, B., Hyman, D., Payne, C., Ruiz, R., Scarlata, C., Sluiter, J., Templeton, D., and Wolfe, J. (2019, June 15). Determination of Total Solids in Biomass and Total Dissolved Solids in Liquid Process Samples. Laboratory Analytical Procedure (LAP), Available online: https:\/\/doi.org\/NREL\/TP-510-42621."},{"key":"ref_36","unstructured":"Sluiter, A., Hames, B., Ruiz, R., Scarlata, C., Sluiter, J., and Templeton, D. (2019, June 15). Determination of Ash in Biomass. Laboratory Analytical Procedure (LAP), Available online: https:\/\/doi.org\/NREL\/TP-510-42619."},{"key":"ref_37","unstructured":"Sluiter, A., Ruiz, R., Scarlata, C., Sluiter, J., and Templeton, D. (2008). Determination of Extractives in Biomass. Laboratory Analytical Procedure (LAP)."},{"key":"ref_38","unstructured":"Sluiter, A., Hames, B., Ruiz, R., Scarlata, C., Sluiter, J., Templeton, D., and Crocker, D. (2019, June 15). Determination of Structural Carbohydrates and Lignin in Biomass. Laboratory Analytical Procedure (LAP), Available online: https:\/\/doi.org\/NREL\/TP-510-42618."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"695","DOI":"10.1351\/pac198759020257","article-title":"Measurement fo cellulase activities","volume":"59","author":"Ghose","year":"1987","journal-title":"Pure Appl. Chem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1515\/hfsg.1982.36.4.177","article-title":"Hydrolyse enzymatique de la ceilulose r\u00e9g\u00e9n\u00e9r\u00e9e","volume":"36","author":"Paquot","year":"1982","journal-title":"Holzforschung"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1336","DOI":"10.1021\/ie071201f","article-title":"Coproduction of oligosaccharides and glucose from corncobs by hydrothermal processing and enzymatic hydrolysis","volume":"47","author":"Garrote","year":"2008","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"4653","DOI":"10.1021\/ie100154m","article-title":"Experimental assessment on the enzymatic hydrolysis of hydrothermally pretreated Eucalyptus globulus wood","volume":"49","author":"Garrote","year":"2010","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"936","DOI":"10.1002\/bit.260260818","article-title":"A comparison of two empirical models for the enzymatic hydrolysis of pretreated poplar wood","volume":"26","author":"Holtzapple","year":"1984","journal-title":"Biotechnol. Bioeng."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"582","DOI":"10.1016\/j.indcrop.2018.08.032","article-title":"Optimization of alkaline pretreatment for the co-production of biopolymer lignin and bioethanol from chestnut shells following a biorefinery approach","volume":"124","author":"Morales","year":"2018","journal-title":"Ind. Crops Prod."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"612","DOI":"10.1016\/j.renene.2019.04.131","article-title":"Multiproduct biorefinery from vine shoots: Bio-ethanol and lignin production","volume":"142","author":"Labidi","year":"2019","journal-title":"Renew. Energy"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"950","DOI":"10.1016\/j.renene.2018.07.131","article-title":"Screening of acidic and alkaline pretreatments for walnut shell and corn stover biorefining using two way heterogeneity evaluation","volume":"132","author":"Tan","year":"2019","journal-title":"Renew. Energy"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.biombioe.2016.03.029","article-title":"Second-generation bioethanol of hydrothermally pretreated stover biomass from maize genotypes","volume":"90","author":"Peleteiro","year":"2016","journal-title":"Biomass Bioenergy"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1186\/1754-6834-6-8","article-title":"Understanding of alkaline pretreatment parameters for corn stover enzymatic saccharification","volume":"6","author":"Chen","year":"2013","journal-title":"Biotechnol. Biofuels"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"276","DOI":"10.1007\/s12010-007-0026-3","article-title":"Potential of agricultural residues and hay for bioethanol production","volume":"142","author":"Chen","year":"2007","journal-title":"Appl. Biochem. Biotechnol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"3000","DOI":"10.1016\/j.biortech.2006.10.022","article-title":"A comparison of chemical pretreatment methods for improving saccharification of cotton stalks","volume":"98","author":"Silverstein","year":"2007","journal-title":"Bioresour. Technol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"3861","DOI":"10.1016\/j.biortech.2010.12.038","article-title":"Pretreatment of switchgrass for sugar production with the combination of sodium hydroxide and lime","volume":"102","author":"Xu","year":"2011","journal-title":"Bioresour. Technol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"313","DOI":"10.3183\/npprj-2000-15-04-p313-318","article-title":"Precipitation of kraft lignin by metal cations during pulp washing","volume":"15","author":"Sundin","year":"2000","journal-title":"Nord. Pulp Pap. Res. J."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1016\/j.jcis.2005.02.005","article-title":"Sorption of Na+, Ca2+ ions from aqueous solution onto unbleached kraft fibers\u2013Kinetics and equilibrium studies","volume":"287","author":"Duong","year":"2005","journal-title":"J. Colloid Interface Sci."}],"container-title":["Agronomy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4395\/11\/1\/155\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:11:25Z","timestamp":1760159485000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4395\/11\/1\/155"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,15]]},"references-count":53,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2021,1]]}},"alternative-id":["agronomy11010155"],"URL":"https:\/\/doi.org\/10.3390\/agronomy11010155","relation":{},"ISSN":["2073-4395"],"issn-type":[{"type":"electronic","value":"2073-4395"}],"subject":[],"published":{"date-parts":[[2021,1,15]]}}}