Investigations into laccase-mediator delignification of kraft pulps

The structure activity effects of l-hydroxy benzotriazole and phthalimide d erivatives as mediators for laccase were studied. Using a softwood kraft pu lp it was shown that the N-hydroxy unit is a key component of 1-hydroxybenz otriazole for efficient laccase mediator delignification to occur. It was a lso found that the 1-hydroxybenzotriazole structure was very sensitive to s ubstituent effects with respect to laccase-mediator delignification. Comput ational results from PM3 indicate that the bond dissociation energy, and el ectronic factors of the radical may contribute to the efficiency of the med iator for LMS delignification.