Production of bioethanol from multiple waste streams of rice milling. (November 2017)

• Record Type: Journal Article
• Authors: Favaro, Lorenzo; Cagnin, Lorenzo; Basaglia, Marina; Pizzocchero, Valentino; van Zyl, Willem Heber; Casella, Sergio
• Is Part Of: Bioresource technology. Volume 244:Part 1(2017)
• Page Start: 151
• Page End: 159
• Publication Date: 2017-11
• Subjects: Rice milling by-products -- Alkaline peroxide pre-treatment -- Enzymatic saccharification -- Consolidated bioprocessing -- Multiple waste streams co-fermentation; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2017.07.108
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Rice milling by-products are promising feedstocks for bioethanol. Starch-rich residues were efficiently fermented by two engineered amylolytic yeast. Rice husk, composed by lignocellulose, was pre-treated with alkaline peroxide. Pre-treated husk was saccharified by commercial enzymes and fermented. Multiple rice by-products were co-processed to ethanol by amylolytic strains. Abstract: This work describes the feasibility of using rice milling by-products as feedstock for bioethanol. Starch-rich residues (rice bran, broken, unripe and discolored rice) were individually fermented (20% w/v) through Consolidated Bioprocessing by two industrial engineered yeast secreting fungal amylases. Rice husk (20% w/v), mainly composed by lignocellulose, was pre-treated at 55 °C with alkaline peroxide, saccharified through optimized dosages of commercial enzymes (Cellic® CTec2) and fermented by the recombinant strains. Finally, a blend of all the rice by-products, formulated as a mixture (20% w/v) according to their proportions at milling plants, were co-processed to ethanol by optimized pre-treatment, saccharification and fermentation by amylolytic strains. Fermenting efficiency for each by-product was high (above 88% of the theoretical) and further confirmed on the blend of residues (nearly 52 g/L ethanol). These results demonstrated for the first time that the co-conversion of multiple waste streams is a promising option for second generation ethanol production.