1. Institut für Pharmazeutische Biologie und Biotechnologie; Heinrich-Heine Universität; D-40225 Düsseldorf Germany
2. Department of Pharmacognosy and Phytochemistry; Faculty of Pharmacy, Ain-Shams University; 11566 Cairo Egypt
3. Department of Pharmaceutical Microbiology and Biotechnology; Faculty of Pharmaceutical Sciences; Nnamdi Azikiwe University; Awka Nigeria
4. Department of Pharmaceutical and Medicinal Chemistry; Faculty of Pharmaceutical Sciences; Nnamdi Azikiwe University; Awka Nigeria