Influences of combination of biological pretreatment with liquid hot water pretreatment on chemical components and enzymatic hydrolysis of Populus tomentosa

Abstract:

[Objective] Enhance the efficiency of fungal pretreatment and lower the severity of liquid hot water (LHW) pretreatment. [Methods] Combinations of white rot fungi and LHW were employed to pretreat Populus tomentosa, the influences of this combined pretreatments on the chemical components and enzymatic hydrolysis of P. tomentosa were studied. [Results] The highest hemicellulose removal of 70.70% was observed by combination of Lenzites betulinus C5617 with LHW pretreatment. Celluloses were degraded in both step of the combined pretreatments, combination of L. betulinus C5617 with LHW caused the highest cellulose loss of 29.62%. Lignin loss happened mostly in the step of fungal pretreatment, and L. betulinus C5617 caused a higher degradation (16.98%) of acid insoluble lignin among the two fungi. The combined pretreatments improved the enzymatic hydrolysis of P. tomentosa significantly. Compared with sole LHW treatment, combination of L. betulinus C5617 with LHW pretreatment resulted in an increase by 20.60%, and an increase (12.23%) of reducing sugar yield were obtained by combination of P. sanguineus D9497 with LHW treatment. [Conclusion] This combined pretreatment can lower the severity of LHW pretreatment and was cost-effective.