Study on the Isolation of Two Atrazine-Degrading Bacteria and the Development of a Microbial Agent

Abstract

Two bacteria capable of efficiently degrading atrazine were isolated from soil, and named ATLJ-5 and ATLJ-11. ATLJ-5 and ATLJ-11 were identified as Bacillus licheniformis and Bacillus megaterium, respectively. The degradation efficiency of atrazine (50 mg/L) by strain ATLJ-5 can reach about 98.6% after 7 days, and strain ATLJ-11 can reach 99.6% under the same conditions. The degradation of atrazine is faster when two strains are used in combination. Adding the proper amount of fresh soil during the degradation of atrazine by these two strains can also increase the degradation efficiency. The strains ATLJ-5 and ATLJ-11 have high tolerance to atrazine, and can tolerate at least 1000 mg/L of atrazine. In addition, the strains ATLJ-5 and ATLJ-11 have been successfully made into a microbial agent that can be used to treat atrazine residues in soil. The degradation efficiency of atrazine (50 mg/kg) could reach 99.0% by this microbial agent after 7 days. These results suggest that the strains ATLJ-5 and ATLJ-11 can be used for the treatment of atrazine pollution.

Comparative study on the biodegradation of chlorpyrifos-methyl by Bacillus megaterium CM-Z19 and Pseudomonas syringae CM-Z6

“…Organophosphorus pesticides generally have a common structure with that of phosphates (or phosphorothioates or phosphoramidates), and microorganisms that degrade such common structures can usually degrade a variety of organophosphorus pesticides. The rate of degradation may be related to the chemical stability of the pesticide itself, the spatial structure, and the feedback effects of the pesticide and the intermediate metabolites on the enzymatic reaction (lee 2011, Ji et al 2016, Zhu et al 2019.…”

Bacillus Megaterium Biodegradation Glycophate

“…has grown on (5,10,15,20,25)ppm concentration of Glph in MSM at 30 ℃ , as the growth of bacteria increased the concentration decreased generally in MSM with Glph in comparative with control in Fig (3,4).The best peak area that showed decreasing in Glph in 30 d were for concentration( 5 ,10) ppm (7, 8)% ,while the 25 ppm showed 28% , while the results of Glph peak area for B.M. incubation for 60 days on MSM, showed the best for (20,15 ) ppm in comparative with control. When compare among the Glph Concentration's via HPLC and degradation ratio% in Fig (5, 6), showed when increase the time incubation to 60 days , the Bacillus megaterium degradation ratio% increased for all Glph concentration's , but the best were for (5, 25)ppm for both the HPLC analysis and Degradation ration%.…”

“…Improve significant degradation ability towards atrazine (50 mg/kg) could reach 99.0% by the microbial agent after 7 days (17).The bacteria show increasing in growth with corresponding increase in glyphosate concentration while B. subtillus show reduction in growth with corresponding increase in glyphosate concentration (18). Other study, showed B.megaterium ability to degradation other organophosphore pesticides, Chlorpyrifos in 7 -14 days , will be potentially useful in abatement of Chlorpyrifos contaminated soil (19).Monocrotophos(MCP), also degraded to carbon dioxide, ammonium and phosphate through formation of unknown compound metabolic by B. megaterium, reached 83% (20). In this study, Bacillus megaterium was isolated from Iraqi Soils and identification by morphological and biochemical tests beside a Sperber's Medium as selectivity media to B.M.…”

Synthesis and Characterization of Clay Polymer Nanocomposites of P(4VP-co-AAm) and Their Application for the Removal of Atrazine

“…The degradation of ATZ can be carried out by both biological and chemical reactions. Biological degradation occurs through the activity of microorganisms and it is considered as the main process by which this herbicide is transformed [6,7,8,9]. However, the degradation of ATZ by means of microorganisms is not the most appropriate technology due to the formation of its metabolites, which are more toxic than the herbicide itself.…”