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Evaluating the Potential of Culms from Sugarcane and Energy Cane Varieties Grown in Argentina for Second-Generation Ethanol Production

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Abstract

The efficient transformation of lignocellulosic biomass into fermentable sugars is essential for building bioeconomies. Sugarcane is an important agricultural crop in a number of Latin American countries, including Brazil and Argentina. Herein culms from two different sugarcane (SC384 and SC724) and two energy cane varieties (EC3116 and EC3118) bred in Argentina were evaluated for sustainable production of second-generation biofuels and green chemicals. Changes in the biomass crystallinity, structure, and morphology introduced by pretreatments were investigated using X-ray diffraction (DRX), confocal laser scanning microscopy (CLSM), and scanning electron microscopy (SEM) techniques. Enzymatic hydrolysis yields of untreated and pretreated sugarcane and energy cane culms were determined and correlated with physical analyses and chemical composition characterizations. Overall, after combined acid and alkali pretreatment, enzymatic convertibility was highly efficient for all studied sugarcane and energy cane varieties, reaching over 97% of theoretical conversion yields. High crystallinity indices and crystallite sizes of pretreated culms and SEM results and CLSM were consistent with the removal of lignin, solubilization of hemicellulose, and amorphous parts of lignocellulose imprinted by the pretreatments. High potential of culms from sugarcane and energy cane varieties cultivated in Argentina for sustainable production of renewable lignocellulosic sugars and their transformation into green chemicals and fuels was demonstrated.

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The data will be made available on request.

Abbreviations

AFEX:

Ammonia fiber expansion

ANOVA:

Analysis of variance

CrI:

Crystallinity index

DRX:

X-ray diffraction

CLSM:

Confocal laser scanning microscopy

EC:

Energy cane culm

EC3116:

Energy cane variety INTA 05-3116

EC3118:

Energy cane variety INTA 05-3118

EHY:

Enzymatic hydrolysis yields

GIMP:

GNU Image Manipulation Program

HPLC:

High-performance liquid chromatography

INTA:

National Institute of Agricultural Technology of Argentina

LPMOs:

Lytic polysaccharide monooxygenases

SC:

Sugarcane (Saccharum spp.) culm

SC384:

Sugarcane variety LCP 85-384

SC724:

Sugarcane variety NA 78-724

SEM:

Scanning electron microscopy

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Funding

This work was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) via Grant 2015/13684-0, by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) via Grants 423693/2016-6 and 303988/2016-9, by Instituto Nacional de Tecnología Agropecuaria (INTA) via Grant PNAIyAV 2019-PE-E6-I114-001, and by Ministry of Science and Technology of Argentina via Grant PICT 2016-1670. This work was also supported by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) via a PhD fellowship to AOK. JMG has a fellowship from Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). We thank the field team of INTA Sugarcane Breeding Program for its technical assistance.

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Authors and Affiliations

  1. São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense, 400, São Carlos, SP, 13566-590, Brazil

    Aissata Ousmane Kane, Vanessa O. Arnoldi Pellergini, Melissa C. Espirito Santo & Igor Polikarpov

  2. Faculté des Sciences et Techniques, Université Cheikh Anta Diop de Dakar (UCAD), B.P. 5005, Dakar-Fann Dakar, Senegal

    Balla Diop Ngom

  3. Agricultural Experimental Station of Famaillá, National Institute of Agricultural Technology (INTA), Famaillá, Tucumán, Argentina

    José M. García & Luis E. Erazzú

  4. National Council of Scientific and Technical Research (CONICET), Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina

    José M. García

  5. Institute of Soils, National Institute of Agricultural Technology (INTA), Castelar, Buenos Aires, Argentina

    Alberto Acevedo

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  1. Aissata Ousmane Kane
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Contributions

AOK: Formal analysis; Investigation; Methodology; Writing—original draft; VOAP: Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Project administration; Validation; Writing—original draft; MCES: Formal analysis; Investigation; Methodology; Writing—original draft; BDN: Supervision; Writing—original draft. JMG: Formal analysis; Investigation; Methodology; Writing—original draft; AA: Formal analysis; Investigation; Methodology; Writing—original draft. LEE: Formal analysis; Investigation; Methodology; Writing—original draft; IP: Conceptualization; Formal analysis; Funding acquisition; Investigation; Methodology; Resources; Supervision; Validation; Writing—original draft; Writing—review & editing.

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Correspondence to Igor Polikarpov.

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Kane, A.O., Pellergini, V.O.A., Espirito Santo, M.C. et al. Evaluating the Potential of Culms from Sugarcane and Energy Cane Varieties Grown in Argentina for Second-Generation Ethanol Production. Waste Biomass Valor 13, 329–343 (2022). https://doi.org/10.1007/s12649-021-01528-5

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