Enhanced enzymolysis and bioethanol yield from tobacco stem waste based on mild synergistic pretreatment

The use of mild pretreatment conditions can significantly lower the cost biorefining process. This study evaluated a approach for tobacco stem waste using combination dilute acid and alkali. By optimizing conditions, we obtained high reducing sugar concentration at temperature <100°C. Increasing or alkali strength in single step did not always improve result; instead, synergistic effect both components was important. To increase bioethanol titer, solid loading, 30%, used fermentation. Compared with batch fermentation, enzyme feeding shorter period (24 h) enhanced production by 4.32%, generating 86.88 g/L bioethanol. results provide valuable insights into effects two-step acid/alkali on enzymolysis. findings suggest that optimized process is efficient