3-Staphylococcus- Inactivation of antibiotic-resistant bacteria by chlorine dioxide in soil and shifts in community composition

https://pubs.rsc.org/en/content/articlepdf/2019/ra/c8ra07997h 

Inactivation of antibiotic-resistant bacteria by chlorine dioxide in soil and shifts in community composition 

M. S. Wu *abc and X. Xud 

To study the efficacy of chlorine dioxide in the inactivation of antibiotic-resistant bacteria in soil, bacteria resistant to penicillin, amoxicillin or streptomycin were screened out from the soils around a hennery. The effects of dosage, contact time and pH value on the killing rates were investigated by batch experiments. The community composition before and after inactivation was analyzed by highthroughput genetic sequencing. The results showed that antibiotic-resistant bacteria are common and widespread in soil and the most resistant species is Staphylococcus aureus. More than 99% of antibioticresistant bacteria could be killed by chlorine dioxide at 5 mg L
1 within 30 min under neutral conditions. The killing log value declined slightly when the pH was changed from 4 to 9. The dominant genus was Sphingomonas, which was sensitive to chlorine dioxide and could be inactivated easily similar to Arthrobacter and Massilia. However, Micromonosporaceae and Thaumarchaeota were more resistant to chlorine dioxide than other species, and their relative abundance increased after disinfection. 

Conclusion 

In this study, we identied bacterial species that are resistant to penicillin, amoxicillin, and streptomycin in the soil around a hennery and the disinfection efficiency of ClO2 on them. Bacteria resistant to penicillin, amoxicillin and streptomycin are common in natural soils. Staphylococcus aureus exhibited the strongest resistance. All the bacteria resistant to penicillin were also resistant to amoxicillin. ClO2 could inactivate ARB in soils effectively, and the effect of pH value was not signicant. Micromonosporaceae and the identied species in Thaumarchaeota were more resistant to ClO2 than Sphingomonas, Arthrobacter and Massilia. At the phylum and class levels, no signicant differences in the bacterial communities were observed between the untreated and ClO2-treated soil samples. Sphingomonas was the dominant genus in the soil before and aer treatment by ClO2. Based on the results obtained, ClO2 could be considered as a suitable disinfectant for ARB in soil.