漆酶改善分离木素和OCC纸浆特性的研究

应用漆酶处理纤维素酶分离酶解木素和OCC(Old corrugated containers)纸浆,结果表明:木素在漆酶处理过程中会发生降解,经漆酶处理后再经加热处理会使木素发生聚合,木素降解主要发生在高分子量木素部分,而聚合作用主要发生在低分子量木素之间;木素经漆酶处理后,酚羟基的含量略有增加,这是由于在漆酶处理木素的过程中,木素不但发生酚氧自由基的离域现象,而且还有高分子量的木素发生降解产生了新的酚羟基;经不同用量的漆酶处理的OCC纸浆手抄片的湿环压指数和湿抗指数与对照样相比均有明显提高,特别是漆酶用量为24 U/g时,湿环压指数达到4.1 N.m/g,提高了41%。经不同用量的漆酶处理的OCC纸浆干环压强度和干抗张强度与对照样相比略有提高,但提高的幅度不大。

Modification of Cellulolytic Enzyme Lignin and OCC with Laccase

In this paper the oxidation of cellulolytic enzyme lignin(CEL) and old corrugated containers(OCC),catalyzed by laccase,was studied.The depolymerization reactions of CEL can have taken place during the laccase treatment.Whereas polymerization in the laccase-treated CEL was observed after a heat-treatment.The CEL depolymerized in the laccase-treatment are high-molecular-weight substrate for laccase.The CEL polymerized in a heat-treatment are low-molecular-weight substrate for laccase.As delocalisation of formed radicals and depolymerization in a high-molecular-weight substrate,the amount of phenolic hydroxyl groups in laccase-treatment CEL was found to increase slightly.Wet ring crush compression strength(RCT) and wet tensile strength of OCC treated with laccase showed significant increases compared to control hand-sheet.For instance,RCT of OCC treated with laccase dosage 24 U/g(pulp) was 4.1 N.m/g,increase of up to 41%.The dry RCT and tensile strength did not show significant increase.