1. Dept. of Chemical and Environmental Engineering, Faculty of Engineering; Universiti Putra Malaysia; Serdang, Selangor Darul Ehsan 43400 Malaysia
2. Dept. of Environmental Sciences, Faculty of Environmental Studies; Universiti Putra Malaysia; Serdang, Selangor Darul Ehsan 43400 Malaysia
3. Institute of Bioscience; Universiti Putra Malaysia; Serdang, Selangor Darul Ehsan 43400 Malaysia