Samin Rahimi - Undergraduate student of Biotechnology, deputy secretary of Maragheh University stem cell Association

The bactericidal effects of Zr nanoparticles have been demonstrated in the past years. Recently, the new anti- microbial compounds of Zr nanoparticles with different formulations have been developed. In this work, zro2 as a new compound of Zr nanoparti- cles, was synthesized and characterized by XRD, TEM, SEM, FTIR, and EDX. The antibacterial activity and the molecular mechanism effects of Zro2 nanoparticles (SNPs) on Escherichia coli DH5α cells were investigated by analyzing the growth inhibitory, H2O2 level, catalase activity, DNA mutation, and plasmid copy number following treat- ment with zro2 nanoparticles. In experimen- tal results, the minimum inhibitory concentration (MIC) was observed in 75 μg/ml and the antibacterial efficacy (ABE) in CFU analysis was estimated 95.3 %. In bacterial cells treated with 75 and 100 μg/ml, H2O2 level significantly increased and catalase activity decreased compared with control. The ran- dom amplified polymorphic DNA (RAPD) was used to eval- uate the effect of Zro2 nanoparticles in DNA damages and mutation in E. coli genome. RADP-PCR results indicated different banding patterns including appearance or disappearance of bands and differences in their intensity.

Zro2 ,Escherichia coli ,DNA mutation ,Oxidative stress