1. Faculty of Science, Department of Chemistry, Universiti Putra Malaysia, Serdang, Malaysia
2. Laboratory of Natural Products, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Malaysia
3. Energy and Environment Unit, Engineering & Processing Division, Malaysian Palm Oil Board, Kajang, Malaysia
4. Centre of Applied Science Studies, Universiti Teknologi Mara, Kuching, Malaysia