DEGUENON, Esther, University of Abomey-Calavi, Polytechnic School of Abomey-Calavi, Research Laboratory in Applied Biology, Research Unit in Applied Microbiology and Pharmacology of Natural Substances, 01 PO BOX 2009 Cotonou, Benin University of Abomey-Calavi,Faculty of Sciences and Techniques, Laboratory in Biology and Molecular Typing in Microbiology, 05 PO BOX 1604 Cotonou, Benin