漆酶/介体体系降解单一纸浆树脂模拟物的研究

以松香酸、亚油酸、油酸、β-谷甾醇、甾醇油酸酯分别作为纸浆中单一树脂的模拟物,采用一种产自黄孢原毛平革菌的漆酶对树脂模拟物进行降解,通过对比漆酶/介体体系的降解效率,筛选了该漆酶合适的介体,探讨了漆酶/介体体系对单一树脂模拟物的降解效果,研究了漆酶/介体体系降解亚油酸和油酸的动力学,并对漆酶降解亚油酸的工艺条件进行了优化。研究结果表明:1-羟基苯并三唑(HBT)是较为合适的介体;漆酶/HBT体系对松香酸、亚油酸、油酸、β-谷甾醇、甾醇油酸酯单一树脂模拟物均有较好的降解效果;漆酶/HBT体系处理亚油酸、油酸的米氏常数分别为1.38和1.86mmol/L,表明亚油酸更易与漆酶/HBT体系结合;该漆酶处理亚油酸的最佳工艺条件为酶用量2.0U/mg、1-羟基苯并三唑介体用量7.6mol/g、时间60min、温度50℃、pH值4.0,此条件下亚油酸的降解率为88.9%,当酶用量增加到4.0U/mg或者处理时间延长至120min时,亚油酸的降解率可达到100%。

Degradation of Single Simulant of Resin in Paper Pulp Usinga Laccase/Mediator System

The laccase produced by Phanerochaete chrysosporium was used to degrade the resin simulants rosin acid,linoleic acid,oleic acid,β-sitosterol,and sterol oleate.By comparing the degradation efficiency of the laccase/mediator system,the most suitable mediator for the laccase was selected.The effects of this system on the degradation of simulants were investigated,and the degradation kinetics of linoleic acid and oleic acid were studied.The technological process conditions for linoleic acid degradation via utilization of laccase were optimized.The results showed that 1-hydroxybenzotriazole(HBT)was a suitable mediator.The laccase/HBT system exerted a better degradation effect on the simulants rosin acid,linoleic acid,oleic acid,β-sitosterol and sterol oleate.The Michaelis-Menten constants of linoleic acid and oleic acid treated by using the laccase/HBT system were 1.38 and 1.86 mmol/L,respectively,indicating that linoleic acid could be more easily combined with the laccase/HBT system;the optimum conditions for the treatment of linoleic acid with laccase included an enzyme dosage of 2.0 U/mg,and a 1-hydroxybenzotriazole mediator dosage of 7.6 mol/g,for 60 min,at 50℃,pH 4.0.The degradation rate of linoleic acid under these conditions was 88.9%;when the enzyme dosage was 4.0 U/mg or when the treatment time was 120 min,the degradation rate achieved 100%.