Comparing the anti-microbial effect of penicillin to that of chlorine dioxide on three opportunistic pathogens

  • Author(s) / Creator(s)
  • Introduction: The discovery of penicillin is a watershed in the history of medicine. Today, antibiotics are a part of everyday life. However, some speculate that society may return to the pre-antibiotic era if the increasing emergence and spread of antibiotic resistant bacteria cannot be slowed. Resistant genes are often carried on plasmids and can spread quickly via horizontal gene transfer. Opportunistic pathogens are key species for developing antibiotic resistance. These pathogens are ubiquitous in nature and live symbiotically on or in humans. After a major infection, transient colonies often remain to spread antibiotic resistance. Because of the growing concern over antibiotic resistance, many people have started looking for natural alternatives to antibiotics. This paper proposes that chlorine dioxide (ClO2) should be considered as an alternative to common antibiotics. ClO2 disinfects via oxidation and is highly selective due to its one-electron transfer mechanisms. Chlorine dioxide is currently used as a common disinfectant in: drinking water, dental practices, and as an aerosol. This paper will compare the anti-microbial effect of penicillin to that of chlorine dioxide on Enterococcus faecalis, Staphylococcus epidermidis and Bacillus subtilis, three opportunistic pathogens. Methods: Part one of the experiment was a phenol coefficient test which was completed to determine the minimum inhibitory concentration (MIC) of chlorine dioxide. In part two, a standard disk diffusion method was completed using the minimum inhibitory concentrations of penicillin and ClO2 on each disk. Results and Conclusion: In part one the MIC of chlorine dioxide was found to be a 1:100 dilution. This concentration is on par with the MIC found for phenol and indicates that ClO2 is as effective as phenol in inhibiting bacterial growth. In part two ClO2 was found to be less effective than penicillin against the three opportunistic pathogens. These results may be erroneous however as, part two, trial two of the experiment, shows evidence for a flawed experimental design. The standard disk diffusion method may not be an accurate way of measuring the antibiotic effectiveness of ClO2 as liquid chlorine dioxide likely dries in the incubator and loses its inhibitory effect. Further avenues of research should be explored to more accurately test the effectiveness of ClO2 on pathogens.

  • Date created
  • Subjects / Keywords
  • Type of Item
    Research Material
  • DOI
  • License
    Attribution-NonCommercial 4.0 International