Bacterial consortia enhance glyphosate breakdown and drive soil microbial dynamics

Abstract

This study assessed the bioremediation potential of four microbial consortia in soil microcosms contaminated with glyphosate, focusing on their metabolic activity and impact on microbial diversity. Among the tested consortia, Con_CC-G—isolated from Conilon Coffee soil that had remained glyphosate-free for three years—demonstrated the most pronounced effects. Microbial metabolic activity was quantified using respirometry, which tracked CO₂ production over 140 h in both inoculated and control soils. Changes in microbial community composition were analyzed using 16S rRNA gene metataxonomics. The results revealed that glyphosate exposure stimulated respiratory activity, particularly in inoculated treatments. Differential abundance analysis revealed significant increases in Achromobacter and Serratia in inoculated microcosms, as well as in other key herbicide-degrading genera. Complementary HPLC-DAD analyses confirmed glyphosate degradation, with Con_CC and Con_CC-G achieving the highest removal efficiencies under both carbon- and phosphorus-limited conditions. These findings provide direct evidence of glyphosate biodegradation and highlight the strong bioremediation potential of Con_CC-G for soils contaminated with this herbicide. Further research must assess its environmental impact and safety before field-scale application.