1. Department of Life and Earth SciencesHigher Teachers' Training College, University of Maroua Maroua Cameroon
2. Department of Animal Biology and Physiology, Faculty of SciencesUniversity of Yaoundé I Yaoundé Cameroon
3. Department of Applied Chemistry, Faculty of SciencesUniversity of Johannesburg Doornfontein South Africa
4. Centre of Endocrinology and MetabolismHudson Institute of Medical Research, Monash University Clayton Victoria Australia
5. Université Côte d'Azur, CNRSInstitut de Chimie de Nice UMR 7272 06108 Nice France