两种漆酶处理对思茅松边材自由基的影响

Effect of Treatment with Two Kinds of Laccases on Free Radical of Pinus kesiya var. langbianensis Sapwood

为消除人造板中游离甲醛污染问题，采用漆酶处理木材生产无甲醛人造板是未来发展的重要方向之一。为探讨漆酶处理木纤维最佳工艺条件，采用两种漆酶（白腐菌漆酶，漆酶Ⅰ、曲酶菌漆酶，漆酶Ⅱ）处理思茅松边材，处理条件为pH（2．0～6．0），温度（30～80）℃，时间为1h,2h．3h，酶用量分别为10u／g、20u／g、30u／g，并测定处理后木材的活性氧自由基（Ros）浓度。结果表明，漆酶处理后思茅松边材ROS浓度显著提高；pH值、温度、处理时间和酶用量对ROS浓度变化均有影响，本试验条件下两种漆酶处理思茅松木材的最佳工艺条件为pH3．0、50℃，2h，20u／g。

Fibreboard without formaldehyde will be manufactured by laccases treated wood fibre to eliminate the pollution of free formaldehyde in the wood-based panels. To obtain the optimum parameters of laccases treatment is fundamental to develop new environmentally friendly fibreboard. The woodflour of Pinus khasya var. langbianensis sapwood and two kinds of laccases （ White-rot fungi, laccase Ⅰ ; AspergiUus, laccase Ⅱ ） were used. Laccase treatment of the sapwood in suspension were conducted under the following conditions： acidity from pH 2.0 to pH 6.0, temperature from 30℃ to 80℃, treatment time respectively for 1 h, 2 h, 3 h and laccase dosages 10 u/g,20 u/g,30 u/g. Free radicals of reactive oxygen species （ROS） were detected after reactions by Electron Spin Reso- nance （ESR）. Compared with control, relative concentration of ROS increased remarkably after woodflour was treated with two kinds of laccases. The optimum reaction parameters were pH 3.0, 50℃, 2 hours and 20 u/g.