The la(iii) complex, was synthesized and characterized by spectroscopy of methods and single-crystal. the antibacterial effects of complex have also been examined in vitro against standard bacterial strains.mic, mbc and inhibition zones of the complex and its ligand and its metal salt against the growth of microorganisms gram- positive (e-coli) and gram-negative(s. aureus) are obtained.
Methods
A solution of la(no3)3·6h2o (1mmol) in h2o was added to solution of 5,5´dimethyl-2,2´bipyridine ligand (2 mmol) that dissolved in methanol-h2o (1:1) (10 ml). the resulting solution was stirred for and left to slowly evaporate at room temperature.(mic) and (mbc) by the broth macrodilution assay in sterile test tubes, and the inhibition zones (iz) by the disk diffusion method. stock solution of the complex was prepared in distilled water and dmso. all the inoculated plates were incubated at 37°c for 24 h. this inhibition zone (iz) assay was performed three times and results averaged.
Results
The mic, mbc and inhibition zones of the complex la(iii) and its ligand and its metal salt against the growth of microorganisms are obtained. cefazolin was used as negative control for gram negative antibacterial activity. the results show that complex la(iii) possesses antibacterial activity, and that this activity is higher than that of the free ligand. this conforms to the overtones concept and tweedy’s chelation theory.
Conclusion
The results of antibacterial show that complex la(iii) possess antibacterial activity, and that this activity is higher than that of the free ligand. comparison of the antimicrobial activities of the synthesized la(iii) compound with similar complexes in the literature shows that our new compound are more strong
