Degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) by fungi originating from Vietnam

Abstract

Three different fungi were tested for their ability to degrade 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid and for the role of laccases and cytochromes P450-type in this process. We studied a white-rot fungus Rigidoporus sp. FMD21, which has a high laccase activity, for its efficiency to degrade these herbicides. A positive correlation was found between its laccase activity and the corresponding herbicide degradation rate. Even more, the doubling of the enzyme activity in this phase corresponded with a doubling of the herbicide degradation rate. It is, therefore, tempting to speculate that laccase is the most dominant enzyme in the degradation of 2,4-D and 2,4,5-T under these conditions. In addition, it was shown that Rigidoporus sp. FMD21 partly relies on cytochromes P450-type for the breakdown of the herbicides as well. Two filamentous fungi were isolated from soil contaminated with herbicides and dioxins located at Bien Hoa airbase. They belong to genera Fusarium and Verticillium of the phylum Ascomycota as judged by their 18S rRNA gene sequences. Both isolated fungi were able to degrade the herbicides but with different rates. Their laccase activity, however, was very low and did not correlate with the rate of breakdown of the herbicides. These data indicate that the white-rot fungus most likely synthesizes laccase and cytochromes P450-type for the breakdown of the herbicides, while the types of enzyme used for the breakdown of the herbicides by the two Ascomycota remain unclear. Graphical abstract

A Review about the Mycoremediation of Soil Impacted by War-like Activities: Challenges and Gaps

“…Like discussions for other soil pollutants from war-like activities, mycoremediation does not appear among the procedures for decontaminating Vietnamese soils containing Agent Orange. Nguyen et al [199] isolated some fungi from Vietnamese soils contaminated with 2,4-D and 2,4,5-T. Subsequently, they used two filamentous fungi to decompose both herbicides in culture media, achieving promising outcomes.…”

Health effects of herbicides and its current removal strategies

“…Moreover, the white-rot fungus Rigidoporus sp. can degrade 2,4-D and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) by producing laccase and cytochromes P450-type for the breakdown of the herbicides [ 92 ].…”

Highly Efficient Removal of 2,4,5-Trichlorophenoxyacetic Acid by Adsorption and Photocatalysis Using Nanomaterials with Surface Coating by the Cationic Surfactant

“…Agent Orange was the most common of these substances, accounting for more than 60% of the total herbicide employed. It is a mixture of n -butyric esters including 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) in equal proportions. , 2,4,5-T appeared to be a useful herbicide originally used as a plant growth hormone analogue . Nevertheless, due to high toxicity and long-lasting persistence that causes harm to human health, 2,4,5-T has been classified as a persistent organic pollutant (POPs) and has been banned for most applications in many countries, including the United States, European countries, and China.…”