Carbon Dioxide as a Microbial Toxicity Enhancer of Some Antibacterial Agents: A New Potential Water Purification Tool

Abstract

The aim of current paper was to investigate the possibility of increasing the toxicity of calcium hypochlorite (Ca(ClO)2) and hydrogen peroxide (H2O2) on Escherichia coli K-12 by preliminary enrichment of culture media by carbon dioxide (CO2). For this purpose, the microbes sensitivity to H2O2 or/and Ca(ClO)2 at normal and CO2-enriched medium was studied by spectrophotometric, radioisotopic, and electronmicroscopic methods. Ten-minute preincubation in CO2-enriched medium enhanced the toxic effect of both H2O2 or/and Ca(ClO)2 on bacteria as a result of induced growth inhibition, compared to no-CO2 enriched group. Additionally, changes in cell morphology and proliferation were observed. It was demonstrated that the preliminary incubation of microbes in CO2-enriched culture media in nonsupercritical concentration elevate the toxic effect of H2O2 or/and Ca(ClO)2 on microbes. This can serve as a novel, effective, inexpensive, and environmentally friendly approach for water purification from bacteria, further improving the protection of the environment and human health.