Synthesis and characterization of lanthanide(III) nitrate complexes derived from two isomeric Schiff base ligands and comparative study of their antimicrobial activity

ABOUT AUTHOR
Muraleedharan Nair. M.K*, Ajitha. P.S, Rejimon. P.K.
Postgraduate & Research Department of Chemistry,
Maharaja’s College, Ernakulam–682011, Kerala, India
Email: [email protected]

ABSTRACT
The ligands and complexes were characterized by elemental analysis, molar conductivity, CHN analysis, magnetic susceptibility measurements, and spectroscopic studies such as IR, UV, and NMR. The in-vitro biological effects of lanthanide nitrate complexes of two isomeric Schiff base ligands were investigated. A comparative study of the zones of inhibition observed for the ligand and coordinated compounds by disc diffusion method against eight human pathogenic bacteria E.coli, K.sps, P.aeruginosa, B.cerus, B.subtilis, S.aureus, S.typhi and K. pneumonia indicated that the synthesized compounds show higher zones of inhibition than that of the free ligands. The ligands and their metal complexes were also evaluated for their ability to inhibit growth of fungi and algae. Isolates of fungi selected were A.niger, F. moneliforme, pleurotus sajor caju and S.acremonium. The cultures of algae, D. salina, Isochrysis, M.chlorella, and Nannochloropsis were selected for the present study.  It is inferred that, increasing the number of chelate rings can increase the lipophilicity of the coordinated complex, which in turn increase antimicrobial activity. Here we report the bio-efficiency of organometallic-based antimicrobials synthesized from two Schiff bases.
Key words: Schiff bases, lipophilicity, lanthanide(III)ions, antimicrobials agents, coordination compounds