Potential of the filamentous fungus Aspergillus niger AN 400 to degrade Atrazine in wastewaters

Abstract

This research aims to evaluate the ability of the fungal specie Aspergillus niger AN 400 to metabolize atrazine (ATZ) in model wastewaters, as most of the research with this worldwide used herbicide is focused on bacteria and on soil bioremediation. Firstly, the tolerance of A. niger for ATZ was evaluated in petri dishes. A. niger growth in all the tested ATZ concentrations, up to 30 mg L −1. Biodegradation of ATZ was then conducted in batch reactors of 3 L, with dispersed fungal biomass. Reactors were operated for 8 days at different conditions: without glucose (RG0) and glucose at concentrations of 0.5; 1.0; 2.0; 3.0; 4.0 and 5.0 g L −1-RG0.5; RG1; RG2; RG3; RG4 and RG5, respectively. Control (RC) includes a reactor in the absence of fungal spores. The highest ATZ removal, 72%, occurred in RG3. At higher glucose concentration, substrate competition kinetics may be the responsible for the decrease of biodegradation rate constants. Only 50% of Chemical Oxygen Demand (COD) removal was obtained due to the presence of methanol used to dissolve ATZ, which has contributed for most of the COD in reactors. Detoxification of the ATZ solution by the biological treatment was observed by the Allium test.

Can white-rot fungi be a real wastewater treatment alternative for organic micropollutants removal? A review

“…with the flow rate ranging from 10 to 40 mL•h -1 and the HRT from 24 to 100 h. Results also showed that the continuous packed bed bioreactor was able to regains its performance quickly after the perturbation in the flow rate. The potential of the same fungus Aspergillus niger to degrade continuously an herbicide, atrazine, in wastewater was evaluated by Marinho et al (2017).…”

Biodegradation of atrazine and ligninolytic enzyme production by basidiomycete strains

“…The proteome analysis indicated that, in this case, extracellular hydrolases and peroxidases were overexpressed in the extracellular environment. Marinho et al [29] found that atrazine degradation by Aspergillus niger in batch reactors containing wastewater and 30 mg L − 1 of the herbicide reached 40% after 8 days. The biodegradation rose up to 72% when the mixture was supplemented with 3 g L − 1 of glucose, allowing more extensive biomass development.…”

Biodegradation of atrazine and ligninolytic enzyme production by basidiomycete strains 

“…The proteome analysis indicated that, in this case, extracellular hydrolases and peroxidases were overexpressed in the extracellular environment. Marinho et al [29] found that atrazine degradation by Aspergillus niger in batch reactors containing wastewater and 30 mg L -1 of the herbicide reached 40% after 8 days. The biodegradation raised up to 72% when the mixture was supplemented with 3 g L -1 of glucose, allowing more extensive biomass development.…”