Degradation of lignin in birch sawdust treated by a novel Myrothecium verrucaria coupled with ultrasound assistance

Combined treatment of a novel fungal endophyte Myrothecium verrucaria coupled with ultrasound assistance was conducted to enhance lignin degradation in birch sawdust. The optimum treatment conditions were confirmed as the materials to liquid ratio 1: 20, temperature 30 degrees C, time 4 days and pH 7, respectively. The results showed that the combined treatment led to the lignin degradation reaching 67.95 +/- 2.14%, while the lignin degradation were 45.50 +/- 2.12% and 13.75 +/- 0.66% with separate fungal treatment and ultrasound treatment, respectively. Moreover, SEM and FTIR analysis indicated that combined treatment significantly altered surface morphology and chemical structure of birch sawdust. The combined treatment greatly increased lignin removal during short time in mild environment. Therefore, these results demonstrated that the combined treatment of fungal endophyte coupled with ultrasound assistance has the high potential for the removal lignin in lignocellulose.