Dissecting the role of heterogeneity and hydrothermal pretreatment of sugarcane bagasse in metabolic pathways for biofuels production

Autor(es)

Soares, Lais Americo ^[1] ; Silva, Edson Luiz ^[2] ; Varesche, Maria Bernadete Amancio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Hydraul & Sanit Engn, Ave JoaoDagnone 1100, Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Chem Engn, Rodovia Washington Luis S-N, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INDUSTRIAL CROPS AND PRODUCTS; v. 160, FEB 2021.
• Citações Web of Science: 0

Resumo

In order to evaluate the effect of sugarcane bagasse (SCB) heterogeneity and hydrothermal (HT) pretreatment on biofuels production, industrial and laboratorial, rind and pith, hydrothermally pretreated (200 degrees C for 10 min at 16 bar and 10 g of SCB mixed with 100 mL of water) and untreated sugarcane bagasse (SCB) were used as substrate (10 g/L) in batch reactors at thermophilic condition (55 degrees C) and initial pH of 6.0. High cellulose content in the hydrothermally (HT) pretreated sugarcane bagasse (SCB) results in hydrogen production (33.7 mmol/L), while lactic acid was the main metabolite produced using laboratorial untreated SCB rind and pith (1.5 and 1.3 g/L, respectively), which caused a decrease in the pH and no hydrogen production. Methane was only observed when industrial untreated SCB pith and rind (5.5 and 3.1 mmol/L), respectively, was used. 16S rRNA sequencing was carried out and at the end of the operation the reactors were fed with untreated laboratorial rind, hydrothermally pretreated industrial rind and untreated industrial pith. Hydrogen-producing bacteria, such as Acetomicrobium (74.4 %) was favored using the HT pretreated fiber, while lactic acid bacteria such as Lactococcus (6.3 %) had a potentially negative effect on the hydrogen-producing bacteria like Thermoanaerobacterium (75.0 %) using laboratorial untreated SCB, since no hydrogen was obtained in this condition. Microorganisms involved in all the anaerobic digestion steps, such as Clostridium (34.4 %), Acetomicrobium (33.4 %), and Methanoculleus (14.8 %) lead to hydrogen, volatile fatty acids (VFA), ethanol, and methane production using industrial untreated SCB. Therefore, this study successfully dissected the detailed microbial community structure and the shift on metabolic pathways as a response of SCB heterogeneity and hydrothermal pretreatment. (AU)

• Processo FAPESP: 17/07194-6 - Análise integrada da degradação de bagaço de cana de açúcar e licor de pentoses em reator anaeróbio de leito fixo compartimentado termofílico
• Beneficiário: Laís Américo Soares
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado