Abstract: The study shows that Eichhornia crassipes can not only concentrate exotic phenol compounds, but also transfer them to other non-toxic ones when grown in an environment containing <150μg. ml^-1 of phenol. Its rhizospheric microorganisms can degradate the exotic phenolic compounds through meta-and orth-pathway. The co-metabolism of phenols by Eichhornia crassipes and its rhizospheric microorganisms could construct a high efficient synergic phenol-degradation biosystem: in media containing 50μg. ml^-1 of phenol, Eichhoria crassing and its rhizospheric microorganisms can degradate phenol only about 1.9% and 37.9%, respectively in 10 hours, but the biosystem can degradate it up to 97.5% under the same condition.

Key words: Eichhornia crassipes, Rhizospheric microorganisms, Synergic phenol-degradation, Co-metabolism