1. Department of Chemistry, Faculty of Science and Mathematics , Universiti Pendidikan Sultan Idris , 35900 Tanjong Malim , Perak , Malaysia
2. Fraser’s Hill Research Center, Universiti Kebangsaan Malaysia , 43600 Bangi , Selangor , Malaysia
3. Atta-ur-Rahman Institute for Natural Product Discovery (AuRIns), Universiti Teknologi MARA , Puncak Alam Campus, Level 9, FF3 Building, 42300 Bandar Puncak Alam , Selangor , Malaysia
4. Faculty of Applied Sciences , Universiti Teknologi MARA , 40450 Shah Alam , Selangor , Malaysia
5. Department of Biological Sciences and Biotechnology, Faculty of Science and Technology , Universiti Kebangsaan Malaysia , 43600 Bangi , Selangor , Malaysia
6. Chemical Sciences Programme , School of Distance Education, Universiti Sains Malaysia , 11800 Penang , Malaysia