Removal of Environmental Pollutants Using White-Rot Fungi Under Heavy Metal Stress

In this study, the ability of Trametes sp. mold to simultaneously remove the pharmaceutical compound metronidazole under lead heavy metal stress from the culture medium was investigated. The effects of different lead concentrations on mold growth, laccase enzyme activity, and the efficiency of biological drug removal were evaluated. The results showed that the presence of lead, even at low concentrations (۵ ppm), significantly reduced laccase enzyme activity. The highest enzyme activity (۱۵۴.۶ U/ml) was observed in the sample without lead, while the lowest activity was recorded in the sample containing ۱۵۰ ppm lead. Drug removal experiments also demonstrated that the predominant mechanism in metronidazole elimination was enzymatic degradation by laccase rather than surface adsorption. In the absence of lead, the removal efficiency reached ۹۴% after ۶ days, whereas this efficiency decreased with increasing lead concentration. This study represents an effective step toward developing sustainable biological methods for the treatment of wastewater contaminated with pharmaceutical compounds and heavy metals.

کلیدواژه ها:

Trametes sp. mold ، metronidazole ، lead heavy metal ، laccase enzyme ، bioremoval