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EPS-mediated coupling between birnessite and degradation bacteria enhances phenanthrene removal
Junxin Jia1, Yaqi Jiao1, Jiaying Gu1
1College of Advanced Agriculture and Ecological Environment, Heilongjiang University, Harbin, 150006, PR China.
Environmental Research
|June 20, 2025
Summary
A new bio-mineral system using birnessite and Novosphingobium sp. HDJX-2 bacteria completely degraded phenanthrene (PHE) in 72 hours. This synergistic approach enhances microbial activity and pollutant degradation for effective environmental remediation.
Area of Science:
- Environmental Science
- Microbiology
- Materials Science
Background:
- Polycyclic aromatic hydrocarbons (PAHs) like phenanthrene (PHE) are persistent environmental pollutants.
- PHE poses significant risks to ecosystems and human health due to its toxicity and persistence.
Purpose of the Study:
- To develop an effective bio-mineral remediation system for phenanthrene (PHE) degradation.
- To elucidate the synergistic mechanisms between microbes and minerals in enhancing PHE remediation.
Main Methods:
- Integration of natural birnessite with the PHE-degrading bacterium Novosphingobium sp. HDJX-2.
- Analysis of microbial-mineral interactions, including changes in birnessite microstructure and bacterial extracellular polymeric substances (EPS).
- Assessment of gene expression, protein profiles, and metabolite changes (glucose, glucosamine) during remediation.
Main Results:
- Complete PHE degradation was achieved within 72 hours using the bio-mineral system.
- Microbial activity modified birnessite, increasing active sites, while birnessite enhanced bacterial activity and EPS secretion.
- Birnessite induced hydrophobic proteins in EPS, improving PHE recognition and binding, alongside increased glucose and glucosamine for better cell dispersion.
Conclusions:
- The bio-mineral system demonstrates efficient and synergistic PHE degradation.
- Microbial-mineral interactions are key to enhancing pollutant bioavailability and catalytic degradation.
- This approach provides a sustainable framework for PAH remediation.
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