Gamma Irradiation Influences the Survival and Regrowth of Antibiotic-Resistant Bacteria and Antibiotic-Resistance Genes on Romaine Lettuce

Conclusion Bacterial communities comprising the lettuce phyllosphere are diverse and harbor a wide array of ARGs, potentially serving as a route of dissemination of antibiotic resistance from leafy vegetables to the human microbiota. With respect to antibiotic resistance and public health concern, the question remains in terms of whether this represents a substantial human health risk (Holzel et al., 2018). Irradiation and washing were found to act synergistically in reducing some ARB and ARGs on the lettuce phyllosphere, and therefore may be viable options for mitigating antibiotic resistance in the food chain. The metagenomic approach applied here provided broad profiling of how these factors influence a broad range of ARBs and ARGs, but deeper sequencing may be necessary to identify effects on more rare, but potentially clinically important, forms of antibiotic resistance. Appropriate models for translating resistome characterization to measures of human health risk are also needed. Judicial uses of antibiotics in livestock, combined with strategic manure management practices likely offer the greatest impact for reducing ARB and ARG loads on produce. The use of hurdles that may further reduce antibiotic resistant bacteria on produce may be warranted, especially for sensitive populations including the immunocompromised. Author Contributions VD, GG, BN, RB, AP, LS, and MP contributed conception and design of the study. BN performed irradiation experiments. VD performed ex...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research