Simultaneous biodegradation of chloro- and methylthio-s-triazines using charcoal enriched with a newly developed bacterial consortium

Abstract

A special type of charcoal, Charcoal A100, was enriched with a newly developed bacterial consortium using a perfusion method. The bacterial consortium consisted of a methylthio-s-triazine-degrading bacterium (Rhodococcus sp. FJ1117YT) and the chloro-s-triazine-degrading bacterial consortium CD7 (containing Bradyrhizobium japonicam CSB1, Arthrobacter sp. CD7w and β-Proteobacteria CDB21). Enriched charcoal was capable of degrading chloro-s-triazines (simazine and atrazine) and methylthio-s-triazines (simetryn and dimethametryn) simultaneously in sulfur-free medium. Almost complete degradation was observed after 4-day cultivation of chloro-s-triazines and 9-day cultivation of methylthio-s-triazines. These triazines were mineralized via their 2-hydroxy analogues.