Synthesis and antibacterial activity of Schiff base metal complexes

This work was performed to synthesize various Schiff base metal complexes using cobalt, nickel and copper followed by their antibacterial activity. Schiff bases were synthesized by the combination of Ethylene-diam in and salicyldehyde. Metal complexes of these Schiff bases were prepared from nitrate and chloride salts of Ni, Co and Cu in an alcoholic medium. The chemical structures of Schiff base metal complexes were established by infrared spectroscopy. The antimicrobial activities of these complexes were checked against Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, Bacillus cereus, Salmonella typhiand Staphylococcus aureus. Disc diffusion method was used to assess their inhibiting potential. The copper based Schiff complex displayed 9.5, 9.0 and 8.0mm zone of inhibitions against E. coli, S. typhi and S. aureusat the concentration level of 16.6μg/ 100μL. The results of antibacterial activity of the copper complexes at the concentration of 33.2μg/100μL showed 18.5, 10.5 and 10mm zone of inhibitions against E. coli, S. typhi and S. aureus. The nickel base complex showed no activity against the tested organisms at both concentrations. The cobalt based Schiff complex showed 17,19,22.5 and 26.5 zones of inhibition against E. coli, B. cereus, K. pneumonia and S. aureus, respectively at16.6μg/100μL. While at 33.2μg/ 100μL this complex displayed 23.5, 30.5, 26.5 and 28.5mm zones of inhibition against E. coli, B. cereus, K. pneumonia and S. aureus. These new derivatives may provide a wide choices and flexibility for the development of new, safe and highly active antibiotics.