Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Adopting Biochar as Immobilization Support for Hyper Ammonia Producing Bacteria Proliferation

The sustainable intensification of agriculture requires innovations that improve nitrogen management while minimizing environmental risks. Biochar has recently emerged as a low-cost, renewable support medium for microbial immobilization in fermentation systems (Manikandan et al., 2023). Yet, its interactions with hyper-ammonia-producing bacteria (HAB), a specialized microbial group capable of elevated ammonia production through amino acid deamination (Chanu et al., 2024), remain poorly characterized. This study investigated how biochar concentration (0.05–0.25% w/v), temperature (30–50 °C), and particle size (250 μm–1.40 mm) influence HAB proliferation during fermentation. Pine wood-derived biochar was combined with enriched cow rumen fluid cultures (Adeniyi et al., 2023; Bello et al., 2023), and microbial growth was monitored over 48 h using optical density (OD₆₀₀). Regression modeling (R² = 0.9931) identified 0.15% biochar, 45 °C, and 250 μm particles as optimal conditions, while higher concentrations inhibited proliferation. Scanning electron microscopy confirmed microbial adhesion and pore colonization patterns (Chen et al., 2024). These results establish the first systematic assessment of HAB–biochar interactions, showing that microbial immobilization depends on the interplay of process conditions rather than single factors. The findings highlight biochar’s potential as a dual-function biofertilizer platform, simultaneously enhancing nitrogen provision and contributing to carbon sequestration (Borchard et al., 2019). Future applications include field-scale validation under varying environmental conditions and integration with circular economy strategies that valorize agricultural residues. References: Manikandan et al., 2023; Chanu et al., 2024; Adeniyi et al., 202