The influence of glucose and NH4NO3 on the degradation of the herbicide atrazine was studied with the marine fungus Periconia prolifica Anastasiou. The bioaccumulation of14C-atrazine by fungal cultures was substantially increased at increased concentrations of glucose. Overall, 34.1% of the initial atrazine concentration was removed from the culture filtrate of the cultures grown in 0.5% (w/v) glucose and 0.007% (w/v) NH4NO3, and 40.4% of the initial atrazine concentration was removed when the same media contained 0.08% (w/v) NH4NO3. The majority of internalized radioactivity from both sets of cultures could be extracted from the mycelia as undegraded atrazine. However, examination of both the culture filtrates and mycelia of cultures grown under 0.5% (w/v) glucose and 0.08% (w/v) NH4NO3 revealed the presence of both dealkylated and dechlorinated hydrolysis products of atrazine. The fungal cultures, compared with uninoculated controls, showed a 5-fold increase in 2-chloro-4-ethylamino-6-amino-striazine (deisopropylatrazine), a 1.9-fold increase in 2-hydroxy-4-ethylamino-6-isopropylamino-s-triazine (hydroxyatrazine), and a 1.5-fold increase in other metabolites not extracted into ethyl acetate, suggesting two separate degradation pathways caused by a combination of metabolic and physicochemical interactions. Although mineralization of [ring-14C] atrazine did not occur under the conditions employed, considerable radioactivity was found in an unextractable form associated with cell fragments of Periconia cultures indicating further metabolism of the initial degradation products.
|Original language||English (US)|
|Number of pages||8|
|Journal||Archives of Environmental Contamination and Toxicology|
|State||Published - Nov 1 1984|