Advanced methanotrophic bioreactor design for efficient bioremediation of hydrogen sulfide (H₂S) And Volatile Organic Compounds (Vocs): Integrating genetic engineering and industrial scalability

The convergence of advanced microbial biotechnology and metabolic engineering has facilitated groundbreaking advancements in bioremediation. This study presents the engineered Methylomicrobium buryatense strain 5GB1C-RO1, optimized for the simultaneous removal of hydrogen sulfide (H₂S) and volatile organic compounds (VOCs) within a two-stage methanotrophic bioreactor system.

Through precise CRISPR/Cas9-mediated genome editing, critical metabolic pathways for sulfide oxidation (SQR, FCCAB, SOXABXYZ) and VOC degradation (alkB, adhP, todC1C2BA) were integrated, achieving catalytic efficiencies exceeding 3.2 × 10⁷ M⁻¹s⁻¹ and substrate conversion rates above 450 nmol min⁻¹ mg⁻¹ protein. The strain demonstrates exceptional robustness under industrial conditions, maintaining 95% pollutant removal efficiency at H₂S concentrations up to 1000 ppm and VOC concentrations exceeding 500 ppm.

The innovative bioreactor system incorporates enhanced gas-liquid mass transfer mechanisms, achieving mass transfer coefficients (kLa) exceeding 300 h⁻¹ and enabling stable operation for over 1000 continuous hours. Experimental results confirm the system's capacity for pollutant mineralization, generating methane-rich biogas (>95% CH₄) and high-protein microbial biomass (>85%), which are valuable for energy and agricultural applications.

This integrated bioremediation approach not only reduces reliance on chemical scrubbing and flaring but also supports circular economy principles by transforming waste gases into renewable resources. The technology provides a scalable, sustainable, and cost-effective solution to mitigate industrial emissions while addressing environmental and regulatory challenges. The findings highlight the potential of combining advanced genetic engineering with innovative bioreactor design to redefine industrial pollutant management and resource recovery.