Impacts of florfenicol on soil bacterial community structure and diversity by high throughput sequencing analysis

Abstract

To investigate the impact of florfenicol on soil microbial community structure and diversity, an indoor florfenicol exposure model was established. Soil samples were collected at different concentrations of florfenicol (0, 0.05, 0.5, 5, and 50 mg/L) on days 0, 7, 30, and 60. High-throughput sequencing was employed to examine the changes in soil microbial community structure, diversity, and abundance. The analysis revealed a total of 31874 operational taxonomic units (OTUs) in the soil samples, averaging 9524 OTUs per sample. The number of soil microbial community OTUs declined with increasing florfenicol concentration. The microbial species richness and diversity showed a decreasing trend at day 7, while the treatment group with 50 mg/L florfenicol at 60 days exhibited the lowest richness index. Examination of the soil microbial community structure identified 50 phyla and 1303 genera. At the phylum level, the abundance of Actinobacteria and Bacteroides decreased with increasing florfenicol concentration. Similarly, at the genus level, some of the dominant genera displayed a decline in abundance with the rise of florfenicol concentration. Cluster analysis demonstrated significant temporal and concentration variability. These findings may provide a theoretical basis for the ecological risk assessment and safe management of florfenicol.