1. Biotechnology Program, School of Agricultural Technology Walailak University, Tasala Nakhon Si Thammarat 80161 Thailand
2. Biomass and Oil Palm Research Center of Excellence Walailak University, Tasala Nakhon Si Thammarat 80161 Thailand
3. School of Engineering Massey University, Private Bag 11 222 Palmerston North New Zealand
4. Research and Development Office Prince of Songkla University Hatyai 90112 Thailand