1. Soil, Plant, Water and Fertilizer Analytical Laboratory, Institute of Agricultural Research for Development, Yaoundé, Cameroon
2. Food Technology Laboratory, Institute of Agricultural Research for Development, Yaoundé, Cameroon
3. Applied Physical and Analytical Chemistry Laboratory, Department of Inorganic Chemistry, Faculty of Science, University of Yaoundé I, Yaoundé, Cameroon
4. Department of Agricultural and Environmental Engineering, College of Technology, University of Bamenda, Bamenda, Cameroon
5. Department of Applied Chemistry, National Advanced School of Agro-Industrial Sciences, Ngaoundéré, Cameroon