Green extractions to obtain value-added elephant grass co-products in an ethanol biorefinery. (20th November 2020)

• Record Type: Journal Article
• Authors: Scopel, Eupídio; Santos, Luana Cristina dos; Bofinger, Matheus Rodrigues; Martínez, Julian; Rezende, Camila Alves
• Is Part Of: Journal of cleaner production. Volume 274(2020)
• Publication Date: 2020-11-20
• Subjects: Supercritical carbon dioxide extraction -- Pressurized liquid extraction -- 2G ethanol -- Lignocellulosic biomass -- Extract -- Plant wax; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2020.122769
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: The replacement of fossil fuels with renewable energy sources depends on the adoption of greener technologies and integrated processes within a biorefinery. In this study, organic molecules with high added value and fermentable sugars were obtained by combined extractions and enzymatic hydrolysis from elephant grass leaves and stems. Fatty acids, sterols, alcohols and phenolics were obtained in different concentrations using green extractions with supercritical carbon dioxide and pressurized liquids (PLE). The extract composition was mainly related to the solvent polarity and the best yield was achieved using water and ethanol as solvents in PLE (7.5% and 7.7% for leaves and stems, respectively). The extractions alone, without any other treatment, were able to increase the enzymatic digestibility of leaves by 50% due to the increase in the substrate wettability. The extractions also did not interfere with the biomass morphology, which allows the posterior use of the substrate for other applications. The results presented herewith showed that adopting extractions as the first step in an ethanol biorefinery is a promising way to achieve the biomass valorization and full use, together with more sustainable processes to obtain chemicals for the food, cosmetic and pharmaceutical industries. Graphical abstract: Image 1 Highlights: SFE and PLE were used to recover elephant grass (EG) extracts for the first time. An integrated approach was used to obtain organic extracts and cellulosic ethanol. Previous removal of extractives does not hinder the subsequent enzyme action. SFE improved in 55% the sugar release in hydrolysis of EG leaves.