Synthetic Biology Approaches for Optimizing Bod Degradation in Hydroponic Systems for Future Food Production

The growing world-wide population and climate-induced agricultural setbacks demand innovative approaches to sustainable food production. Hydroponic systems offer promising solutions through resource-efficient, soilless cultivation methods suitable for urban and drought-prone regions. However, the build-up of organic matter in recirculating nutrient solutions elevates biochemical oxygen demand (BOD), leading to dissolved oxygen depletion, disrupted microbial balance, compromised plant health, and potential food safety risks through pathogen proliferation. This review examines synthetic biology as a strategy for optimising BOD degradation in hydroponic systems. We explore the application of genetically engineered microorganisms, including Bacillus subtilis , Pseudomonas putida , and Rhodococcus species, equipped with enhanced catabolic pathways for targeted organic matter degradation. Advanced genetic tools such as CRISPR-Cas9 gene editing, metabolic pathway engineering, and synthetic microbial consortia design are evaluated for their efficacy in maintaining water quality while supporting crop productivity. The integration of biosensor technologies, Internet of Things (IoT) platforms, and real-time monitoring systems allows for dynamic, feedback-responsive bioremediation strategies. Comparative assessments demonstrate synthetic biology's benefits over traditional BOD management methods in terms of specificity, energy efficiency, adaptability, and environmental sustainability. We address biosafety mechanisms (kill switches, auxotrophy), regulatory frameworks, ethical implications, and public acceptance challenges. This review highlights successful pilot implementations, discusses scalability for commercial operations, and identifies future research directions, emphasising interdisciplinary approaches, long-term ecological impact assessments, and cost-effective designs for small-scale farmers. Ultimately, synthetic biology-based BOD optimisation offers a strategic pathway toward resilient, sustainable, and safe hydroponic food production systems that contribute to global food security.