1. a School of Materials, Energy, Water and Environmental Sciences (MEWES), The Nelson Mandela African Institution of Science and Technology, P.O. Box 447, Arusha, Tanzania
2. b College of Natural Resources Management and Tourism, Mwalimu Julius K, Nyerere University of Agriculture and Technology, P.O. Box 976, Musoma, Tanzania
3. c Department of Molecular Biology and Biotechnology, College of Natural and Applied Sciences University of Dar es Salaam, P.O. Box 35179, Dar es Salaam, Tanzania
4. d Department of Health and Biomedical Sciences, School of Life Sciences and Bio-engineering, The Nelson Mandela African Institution of Science and Technology, P.O. Box 447, Arusha, Tanzania