Chemical Modification of Laccase from Aspergillus oryzae and its Application in OCC Pulp
Yangmei Chen,
Jinquan Wan,
Qitang Wu,
Yongwen Ma
Affiliations
Yangmei Chen
Key Laboratory of Soil Environment and Waste Reuse in Agriculture of Guangdong Higher Education Institutes, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, P.R. China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, PR China; China
Jinquan Wan
College of Environment and Energy, South China University of Technology, Guangzhou 510006, P.R. China; China
Qitang Wu
Key Laboratory of Soil Environment and Waste Reuse in Agriculture of Guangdong Higher Education Institutes, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, P.R. China; China
Yongwen Ma
College of Environment and Energy, South China University of Technology, Guangzhou 510006, P.R. China; China
Laccase activity and stability were improved and modified through the interaction between laccase amino acid residues (e.g., amino groups (-NH2) and carboxyl groups (-COOH)) and the chemical reagents thiourea dioxide (TDO) and L-phenylalanine methyl ester hydrochloride (L-PME). Compared with the control sample, the activity of the laccase modified with these chemical reagents was increased by 209% and 50%, respectively. The stability of the laccase modified with L-PME increased by 56.9%. However, the laccase modified with TDO only improved slightly. It was clear that reagent L-PME was more efficacious than TDO. The paper formed with addition of L-PME-modified laccase exhibited better performance in terms of tensile strength, bursting strength, and tear strength, which increased by 13%, 10%, 9%, respectively, compared with the paper formed with unmodified laccase.
