Screening of Lignin-degrading Fungal Strain and Its Pretreatment of Distillers'Grains
In order to address the biological resistance of lignin during biomass refining,this study selected a lignin-degrading fungal that was used for the distillers'grains pretreatment.Fourier infrared spectrometer,X-ray diffractometer,scanning electron microscopy,Zeta potential and nanoparticle size analyzer,low-field nuclear magnetic resonance analyzer,and thermogravimetric analyzer were used to characterize the microstructure and physicochemical properties of distillers'grains before and after preconditioning.The results showed that this lignin-degrading strain was the genus Trametes,named Trametes sp.SCU31(T.sp.SCU31).T.sp.SCU31 was able to efficiently degrade lignin in distillers'grains,which could degrade acid insoluble lignin and acid soluble lignin by 33.86%and 50.88%,respectively.The surface of distillers'grains pretreated by T.sp.SCU31 was covered with holes and fragments,resulting in the exposure of more fiber bundles and a significant increase in the accessibility of cellulase.These results indicated that the T.sp.SCU31 pretreatment efficiently degraded lignin and disrupted lignocellulosic resistance.