Effect of homemade compound microbial inoculum on the reduction of terramycin and antibiotic resistance genes in terramycin mycelial dreg aerobic composting and its mechanism

In order to tackle the issue of terramycin mycelial dreg (TMD) diagnosis and removal of terramycin and anti-biotic resistance genes (ARGs), this study adopted aerobic composting (AC) technology and added homemade compound microbial inoculum (HCMI) to promote the AC of TMD and enhance the removal of terramycin and ARGs. The findings demonstrated that terramycin residue could be basically harmless after AC. Moreover, HCMI not only reduced QacB and tetH but also increased the degradation rates of VanRA, VanT, and dfrA24 by 40.81%, 5.65%, and 54.18%, respectively. The HCMI improved the removal rate of ARG subtypes to a certain extent. According to redundancy analysis, during AC, the succession of the microbial community had a stronger in-fluence on the variance of ARG subtype than the environmental conditions. Differences in the abundance of various bacteria due to changes in temperature may be an intrinsic mechanism for the variation of ARG subtypes.

Automated summary

This study aimed to address the problems of diagnosing terramycin mycelial dreg (TMD) and removing terramycin and antibiotic resistance genes (ARGs). Aerobic composting (AC) technology was used along with homemade compound microbial inoculum (HCMI). The results showed that terramycin residues became harmless after AC. HCMI reduced QacB and tetH and increased the degradation rates of VanRA, VanT, and dfrA24. The HCMI also improved the removal rate of ARG subtypes to a certain extent. The succession of the microbial community during AC had a stronger influence on the variance of ARG subtypes than the environmental conditions, possibly due to changes in temperature affecting the abundance of various bacteria.