Study on the cooperation mechanism of urea-hydrolysis bacteria and biosurfactant bacteria for dust suppression

[Display omitted] •A new strategy has been proposed to achieve dust prevention and control.•Urea-hydrolysis bacteria could provide fatty acids for biosurfactant production.•Biosurfactant bacteria could provide an alkaline environment for mineralization. To solve the problems of poor wettability and difficult penetration of microbial dust suppressants caused by the strong hydrophobicity of coal dust, a biosurfactant bacteria (previously screened in coal dust, strain P) and a urea-hydrolysis bacteria (also screened in coal dust, strain X) were co-cultured. In addition, the growth characteristics, mineralization, and emulsification performance of the compound bacteria under different inoculation sequences (P14X, X14P, PX, P24X, and X24P) were studied. Results showed that strain P may inhibit the diffusion of the strain X, but ultimately can synergistically grow and increase the urease activity of co-culture system. It also can be found that the compound bacteria P14X exhibited quite high mineralization and emulsification characteristics. The cooperation mechanism of these two bacteria was explored using the non-targeted gene metabolomics analysis, which found that strain X in co-culture systems can provide fatty acids for the production of biosurfactants and promote the synthesis of rhamnolipids. At the same time, strain P can provide an alkaline environment for the occurrence of mineralization in co-culture systems and promote the generation of CaCO3. The preparation of microbial dust suppressants based on compound bacteria can provide theoretical basis and data support for the application of microbial dust suppressants in the field of coal dust prevention and control.