Microbial diversity of dishwashers in different cities of China in spring, summer, autumn and winter

More and more Chinese families are using dishwashers, consumers have paid special attention to the sterilization and disinfection function of dishwashers in recent years. However, there is still a lack of research on the distribution of microorganisms in dishwashers nationwide in China. In order to better upgrade the sterilization and disinfection functions of dishwashers, the plate culture method and high-throughput sequencing technology were used to comprehensively analyze the microbiology of household dishwashers in different cities of China in spring, summer, autumn and winter in this study. A total of 1109 strains of bacteria were isolated from dishwashing machine samples by culturable method, including 706 strains of bacteria distributed in 72 genera, 403 strains of fungi distributed in 52 genera.The most frequently isolated bacteria were Bacillus, Pseudomonas, Brevibacillus, Exiguobacterium, and Acinetobacter. The most frequently isolated fungi were Aspergillus, Penicillium, Exophiala, Fusarium, and Candida. A total of 3779 OTUs were obtained from bacteria and 1541 OTUs were obtained from fungi by amplicon sequencing. The results of culture-independent analysis were consistent with those of culturable analysis. This study laid a foundation for the directional screening of superior microbial resources in dishwashers. It provided data support for the further upgrading of the sterilization and disinfection function of the dishwasher.