Biodegradation of atrazine, glyphosate and pendimetaline employing fungal consortia

Abstract

The objective of the present study was to evaluate the bioremediation of soils artificially contaminated with atrazine, glyphosate and pendimethalin by fungal consortia in biodegradation processes in microcosms. Biodegradation was evaluated from microbial respiration over a period of 15 days and genotoxicity analysis in Allium cepa roots exposed to elutriate samples at zero and 50 μg mL-1 concentrations of the herbicides after the biodegradation process. The results were submitted to analysis of variance, the Tukey test and the Fischer test (p<0.05%) for comparison of means. The Aspergillus fumigatus - Penicillium citrinum consortium had a larger capacity to degrade atrazine but metabolism was inhibited in the presence of glyphosate and pendimethalin. There was a delay in the mitotic index in the meristematic cells of the Allium cepa roots exposed to the elutriates in the 50 μg mL-1 atrazine and pendimethalin concentration. There was a cellular alteration in the metaphase phase of the cells exposed to the elutriates at the 50 μg mL-1 concentration of the three herbicides. The changes occurred were low, indicating that there was degradation of part of the herbicides.

Microbes as a potential bioremediation tool for atrazine-contaminated soil: A review

“…A large range of microorganisms involved in the degradation of atrazine leads to the production of metabolites while some other microorganisms derive their nutrients and energy by mineralizing them completely into CO 2 and NH 4 + [19]. Atrazine degrading microorganisms are not limited to only bacteria and fungi, but many microalgae; for example, Chlamydomonas mexicana, Chlorella sp., and Selenastrum capricornutum have also been reported by several researchers [20,21].…”

“…The genes atzABC identified from Pseudomonas sp. strain ADP that homology to five atrazine-degrading microbial Metarhizium robertsii Ascomycota nd 2-hydroxy atrazine and desethylatrazine [63] Aspergillus niger AN 400 Ascomycota nd Deethylatrazine ( DEA), deisopropilatrazine (DIA), hydroxyatrazine (HA) [64] Penicillium chrysogenum NRRL 807 Ascomycota nd nd [13] Saccharomyces cerevisiae Ascomycota nd Hydroxyatrazine, deethylatrazine, deisopropylatrazine [22] Aspergillus fumigatus Penicillium citrinum Ascomycota nd nd [19] In the table, nd=no data obtained in the cited reference.…”