In this work, laccase treatment was employed to enhance nanofiltration process by lignin removal. Results showed that the membrane filterability was increased in terms of deionized water flux and PHL filtration process. On the other hand, the hemicellulosic sugars were negligible affected and can be concentrated to 172 g/L, which was increased about 300% from the original one. The combined laccase-nanofiltration process provides an alternative approach to utilize hemicellulosic sugars of PHL in an environmentally friendly way. (C) 2015 Elsevier Ltd. All rights reserved.