Bioconversion of Sugarcane Bagasse into Value-Added Products by Bioaugmentation of Endogenous Cellulolytic and Fermentative Communities

The goals of this study were to describe a comprehensive taxonomic profile of bacterial communities endogenous from sugarcane bagasse (SCB) and from a thermophilic sludge formed mainly by Proteobacteria Actinobacteria and Firmicutes phylum and its potential as a bioaugmented inoculum for degradation of lignocellulosic biomass. Batch assays were performed using SCB as substrate at different condition: (RC) 2 g L−1 glucose, (R1i) 2 g L−1 unpretreated SCB, (R2i) 2 g L−1 hydrothermally pretreated SCB (at 210 °C for 15 min), (R3i) 2 g L−1 hydrothermally pretreated SCB (at 210 °C for 15 min) followed by alkaline delignification (NaOH—1 M), (R4i) 1 g L−1 unpretreated SCB plus 1 g L−1 hydrothermally pretreated SCB (at 210 °C for 15 min) followed by alkaline delignification. Hydrogen, methane and organic acids were the main metabolites produced during the fermentation. Maximum hydrogen (2.01 and 1.09 mol H2 mol−1 consumed soluble carbohydrates) were obtained in R1i and R2i, respectively. The highest organic acid (1051 mg L−1) and methane (0.92 mmo L−1) production were obtained in R4i.