Spectrophotometric and biological studies for the interaction of rifaximin with Co, Cu, Fe and vitamin C

Abstract

The interaction of Rifaximin with Iron, Copper, Cobalt and Vitamin C was studied by Uv-Vis. spectrophotometric technique at different pH and time intervals. The maximum absorbance bands for Co, Fe and Cu rifaximin complexes were 446 nm, 397 nm and 241 nm respectively. The molar ratio method was used to the most stable stoichiometries for the prepared complexes. The yellow color that formed from the interaction of rifaximin with vitamin C, allowed its determination spectrophotometry. The antimicrobial activities of Iron, Copper and Cobalt complexes with Rifaximin against standard human pathogenic Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram negative) using agar diffusion method were studied. Iron and Cobalt complexes were found to exhibit higher zone of inhibition against the tested pathogens while copper inhibit completely the effect of Rifaximin. The biological study for Rifaximin - Vitamin C mixture, vitamin C decreased the effect of the antibiotic on staphylococcus, and this inhibition effect increased on E-coli.