Evolution of the earthworm (Eisenia fetida) microbial community in vitro and in vivo under tetracycline stress.

ABSTRACT

Bioremediation of contaminated soil has received increasing attention, and the effects of antibiotic residues on the soil ecological environment are a current research hotspot. Earthworms are the first choice of soil organisms to indicate the degree of soil pollution, and their detoxification mechanism after antibiotic stress must be further explored. Taking Eisenia fetida as the research object, an antibiotic (tetracycline) stress test was carried out in sterile artificial soil. The stress concentrations were set at 0, 0.3, 3, 30, 300 and 600 mg/kg. The ECO method was used to cultivate microbes in earthworms and soil. The carbon source utilization intensity algorithm developed by our team was used for data statistics, and a factor analysis model was constructed to explore the succession process of microbes of earthworms in vivo and in vitro under tetracycline stress. The results showed that there were four processes in the evolution of microbes under short-term tetracycline stress at 1-3 days, the microbes in worms played a leading role; at 4-5 days, the microbes in the worms and the soil microbes jointly resisted TET stress; after 6-8 days of stress, the microbes in worms still played the main role, but their role was weakened; and after 9-10 days, soil microbes played a leading role, and tolerant microbes appeared. Under long-term stress, the microbes of earthworms in vivo and in vitro were obvious different, and there may be no regulatory relationship. And the factor analysis model is suitable for the analyse of the changes in microbial communities in vivo and in vitro under TET stress. The research results provide a reference method and model basis for the bioremediation of antibiotic-contaminated soil and the study of earthworm detoxification mechanisms, and help agricultural development.