Synthetic Microbial Consortia for Targeted Biodegradation of Butachlor and Related Herbicides

The study presented here outlines the development of a precise synthetic microbial consortium, termed SMC1, designed to efficiently break down butachlor. The constituent bacterial strains were sourced from various herbicide-contaminated environments and identified as Serratia ureilytica, Enterobacter cloacae, and Pseudomonas putida. Results indicate that SMC1 effectively degrades high concentrations of butachlor in both soil and aqueous environments, overcoming inhibitory effects observed when using individual bacterial strains. SMC1 demonstrated resilience to butachlor concentrations of up to 2000 mg/L, degrading 60% of the initial concentration within 200 hours in aqueous solutions. Furthermore, the consortium exhibited efficient degradation of other commonly used herbicides, such as glyphosate and alachlor. Enhancing the biodegradation efficiency of SMC1 at higher butachlor concentrations was achieved through cell immobilization within alginate beads. This technique facilitated sustained enzymatic activity and prolonged exposure to herbicide contaminants. Comparative analysis between freely suspended cells and immobilized cells revealed complete removal of up to 1500 mg/L of butachlor within 168 hours with immobilized cells, while freely suspended cells achieved only 70% degradation efficiency at the same concentration. These findings highlight the potential of a SMC1 for effective biodegradation of butachlor and other herbicides, suggesting scalability for industrial-scale wastewater treatment applications.