Design of experiments driven optimization of alkaline pretreatment and saccharification for sugarcane bagasse

To maximize the sugar release from sugarcane bagasse, a high-resolution Fractional Factorial Design (FFD) was combined with a Central Composite Orthogonal (CCO) design to simultaneously evaluate a wide range of variables for alkaline pretreatment (NaOH: 0.1-1 mol/L, temperature: 100-220 degrees C, and time: 20-80 min) and enzymatic saccharification (enzyme loading: 2.5-17.5%, and reaction volume: 550-850 mu L). A total of 46 experimental conditions were evaluated and the maximum sugar yield (423 mg/g) was obtained after 18 h enzymatic hydrolysis under optimized conditions (0.25 mol/L NaOH at 202 degrees C for 40 min, with 12.5% of enzyme loading). Biomass compositional analyses showed that the pretreatments strongly removed lignin (up to 70%), silica (up to 80%) and promoted cellulose enrichment (25-110%). This robust design of experiments resulted in maximizing enzymatic hydrolysis efficiency of sugarcane bagasse and further indicated that this combined approach is versatile for other lignocellulosic biomasses.

Automated summary

By combining a high-resolution Fractional Factorial Design with a Central Composite Orthogonal design, the study successfully optimized the conditions for alkaline pretreatment and enzymatic saccharification of sugarcane bagasse. This resulted in maximizing sugar release and biomass compositional changes, indicating the versatility of this approach for other lignocellulosic biomasses.