利用固定化技术与添加表面活性剂增强双酚A降解率的研究

Enhanced laccase catalyzed degradation of bisphenol A by immobilization technology and surfactant addition

以SiO_2为载体,戊二醛为交联剂,用以固定游离态漆酶降解双酚A(Bisphenol A,BPA).同时,对比了游离态漆酶与固定化漆酶在不同pH值与温度下的最佳酶活与酶稳定性,再通过添加表面活性剂来增加酶活及BPA去除效果.结果表明,与游离态漆酶相比,固定化漆酶对不同酸碱的适应性与耐热性均有所提高,在pH为2~8时,固定化漆酶的活性均高于游离态漆酶,且最佳活性温度也从游离态漆酶的40℃提高至50℃.在BPA降解率方面,固定化漆酶的降解率皆高于游离态漆酶,反应6 h后,对100 mg·L^(-1)BPA的去除率可分别达到92%与85%.通过添加非离子型表面活性剂Triton X-100,反应4 h后固定化漆酶可完全降解BPA,相对活性为67%;游离态漆酶于6 h将BPA降解完全,相对活性为32%.实验证实Triton X-100可作为酶活诱导剂用以提高漆酶活性及BPA的降解率,降低了处理成本且具有一定的应用前景.

Laccase was immobilized on silica with glutaraldehyde as crosslinking agent to degrade bisphenol A （BPA）.The optimum activity and stability of free and immobilized laccase under different pH and temperature were investigated.Nonionic surfactant was added to further enhance the activity of laecase in the degradation of BPA.The results indicate that immobilized laccase had higher adaptability to pH and thermal stability than the free one in the pH range of 2 to 8 with higher activity.The optimum temperature of immobilized laccase was 50 ℃ , which was higher than free laccase （ 40℃ ）.After 6 hours, the degradation efficiency of BPA was 92% and 85% by immobilized and free laccase, respectively. With addition of Triton X-100, the degradation efficiency of 100 mg·L-1 BPA reached 100% of removal by immobilized laccase in 4 hours with relative activity of 67%, while it took 6 hours for tbe free laccase with relative activity of 32%.The results show that the activity of laccasc and the BPA removal efficiency were improved by the presence of Triton X-100,which could reduce the processing cost with good potential in application.