Abstract
Bioethanol production from non-food lignocellulosic material is one of the most important topics in the field of biofuel production. We report on experiments with a treatment for the production of fermentable sugars from the fibrous parts of alfalfa (Medicago sativa L.), a widely used forage plant. The process is divided into several consecutive steps: ball milling, microwave assisted pretreatment in aqueous medium and enzymatic hydrolysis with a mixture of cellulase and β-glucosidase leading to the final production of fermentable sugars. This process was followed by a detailed HPLC analysis for the detection of sugars, oligomers and by-products, such as furfural, hydroxymethylfurfural and acids. Scanning electron microscopy was used for a visual characterization of the material throughout all these steps. Several plant structures were identified and their successive changes during the different treatment steps were monitored and followed.
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Acknowledgments
We thank Dr. Grandi for the alfalfa straw. Authors gratefully thank Alma Mater Ticinensis for the financial support. We thank Dr. Nadia Iazzi for the help on the data analysis and the support during all the research. We thank Ministero Politiche Agricole e Alimentari of Italy for funding of BI.CE. Project (Bioetanolo Cellulosico-Biocombustibili di seconda generazione).
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Dondi, D., Zeffiro, A., Nola, P. et al. Structural modification of alfalfa stems during hot water and enzymatic hydrolysis for sugar production. Cellulose 22, 1853–1860 (2015). https://doi.org/10.1007/s10570-015-0580-8
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DOI: https://doi.org/10.1007/s10570-015-0580-8