Fusarium concolor X4 Pretreatment Suppresses Light-Induced Yellowing of High-Yield Pulp

High-yield pulps (HYPs), such as CTMP (chemi-thermo-mechanical pulp), are attractive due to their low cost and high wood utilization. However, their drawback of rapid brightness reversion (yellowing) limits wide use of the HYPs. In this study, a fungus, Fusarium concolor X4, was applied to treat poplar CTMP for exploring the effects of biotreatment on brightness and light-induced yellowing of the pulp. The results indicated that the biotreatment with Fusarium concolor X4 could improve the brightness of poplar CTMP and inhibit light-induced yellowing of the pulp. The yellowing inhibition mechanism was explored by the analysis of enzyme production regularity during biotreatment, changes in chemical components, and the UV-Vis absorption spectra and FTIR-ATR spectra of pulps before and after biotreatment.