title: Degradation of ethylenediaminetetraacetic acid by mictobial populations from an aerated lagoon.
abstract: The ferric chelate of ethylenediaminetetraacetic acid (EDTA) was biologically degraded by a mixed population of microorganisms present in an aerated lagoon receiving this chemical in its feed. As determined radiorespirometrically, 28% of the acetate-2-C and 30% of the ethylene position of the ammonium ferric chelate of [14C]EDTA was recovered as 14CO2 after 5 days. In a separate experiment using gas liquid chromatography and the sodium ferric chelate, as much as 89% disappearance of EDTA (0.1% wt/vol) was observed during a similar time period. Optimum 14CO2 evolution was observed at a pH value between 7 and 8 and at room temperature. Degradation of NH4Fe-[2-14C]EDTA was stimulated by the addition of either unlabeled NaFe-EDTA, nitrilotriacetic acid or ethylenediamine, and inhibited by the addition of a variety of different sugars and amino acids. Consistent with the biological nature of this degradation, little or no 14CO2 evolution was observed after heat treatment of the microorganisms at 100 C for 10 min, or after the addition of antibiotics to the incubation mixtures. Gas-liquid chromatography and mass spectral analyses were performed to demonstrate EDTA disappearance and to identify possible intermediates of EDTA degradation.
mesh_terms: D000085:Acetates; D000332:Aerobiosis; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002245:Carbon Dioxide / Q000096:biosynthesis; D002250:Carbon Radioisotopes; D055598:Chemical Phenomena; D002621:Chemistry; D002849:Chromatography, Gas; D004492:Edetic Acid / Q000378:metabolism*; D005029:Ethylenediamines / Q000378:metabolism; D005030:Ethylenes; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry; D009571:Nitrilotriacetic Acid / Q000378:metabolism; D013696:Temperature; D014871:Water Microbiology
chemical_list: D000085:Acetates; D000900:Anti-Bacterial Agents; D002250:Carbon Radioisotopes; D005029:Ethylenediamines; D005030:Ethylenes; D002245:Carbon Dioxide; D004492:Edetic Acid; D009571:Nitrilotriacetic Acid