Activity of Heterocyclic Tellurium Derivatives Against Opportunistic Bacteria

Abstract

Antimicrobial resistance is a serious challenge for medicine and society as a whole. Among the bacteria that pose the greatest threat to human health due to their growing antibiotic resistance are Escherichia coli, Staphylococcus aureus and Salmonella spp. The main reasons behind this problem are the misuse of antibiotics and lack of new antimicrobials, which are difficult to develop due to the complexity of the mechanisms of microbial infections and their limited weak points. Moreover, the process of developing new drugs requires significant time and financial resources. The purpose of this article was to analyse the antibacterial properties of three tellurium derivatives against infections caused by E. coli, S. aureus and Salmonella spp. Materials and methods. During the experiment, we studied the antimicrobial activity against the abovementioned bacteria of the following organotellurium compounds of original synthesis that have not been previously described in literature: dioxyrocyclo-[4-methylphenyl] tellurochloride, 3-chloromethyl-dioxisinrocyclophenyl tellurochloride, and ethyltellurobenzal-[2-methoxy-3,5-dichloro] aniline. As a criterion for the microorganism’s sensitivity to organotellurium compounds, inhibition zone diameter was used. The paper applied the serial dilution method and the disk diffusion method. Results. The study of the three heterocyclic tellurium derivatives in various concentrations revealed a significant antibacterial effect of dioxyrocyclo-[4-methylphenyl] tellurochloride, whose minimum suppressive and minimum inhibitory concentrations against the bacteria in question we were able to determine. Minimum inhibitory concentrations for E. coli and S. aureus were 18.60 and 1.35 µg/ml, respectively. Disk diffusion showed that the inhibition zones range between 3 and 6 mm. E. coli and S. aureus strains were particularly sensitive to this compound. Ethyltellurobenzal-[2-methoxy-3,5-dichloro] aniline failed to produce a positive effect against E. coli, S. aureus and Salmonella spp. at any regimen, while 3-chloromethyl-dioxisinrocyclophenyl tellurochloride demonstrated moderate antimicrobial activity at a relatively low bacterial load.

Keywords

• organotellurium compounds
• antibacterial properties
• minimum inhibitory concentration
• minimum suppressive concentration
• staphylococcus aureus
• escherichia coli
• salmonella