Combination of High Solid Load, On-site Enzyme Cocktails and Surfactant in the hydrolysis of Hydrothermally Pretreated Sugarcane Bagasse and Ethanol Production.

In this study, the combined strategy of using high solid load, on-site enzyme cocktails and surfactant was evaluated in saccharifications of hydrothermally pretreated sugarcane bagasse (HP-SB) and ethanol production. The hydrolyses were carried in fed-batch mode with a solid load of 10–40% (w/v) at time intervals of 12 h, using two homemade enzyme extracts (ES1 from Aspergillus niger monoculture and ES2 from A. niger, Trametes versicolor and Pleurotus ostreatus consortium), 10 FPU/gds of cellulase loading at 50 °C for 72 h. After optimization of solid loading, new saccharifications were performed with the addition of 5% (w/v) surfactant (Triton X-100). The HP of SB led to a significant reduction of 69.26% in hemicelluloses content, but also preserved the cellulose fraction in HP-SB. The increase of HP-SB load in hydrolysis from 10 to 35% significantly improved the release of total reducing sugars (TRS), with an increase of 188.54% in ES1 and 177.46% in ES2. The use of Triton X-100 in saccharifications of HP-SB (30% w/v) also positively contributed to TRS production, with an increase in TRS of 6.22% in ES1_S and 24% in ES2_S. The fermentation of the hydrolysate after surfactant-assisted hydrolysis of HP-SB (30% w/v) led to an ethanol yield of 81.70% for F1_S and 88.03% for F2_S. Results demonstrated that the integrated use of high solid load, low-cost on-site enzyme cocktail and surfactant (Triton X-100) can be a promising approach to improve the efficiency of bioconversion of lignocellulosic biomass to fermentable sugars. [ABSTRACT FROM AUTHOR]