Degradation of parathion in culture by microorganisms found in cranberry bogs

Oxygen concentration and different carbon sources drastically altered parathion degradation in culture media inoculated with microorganisms from Wisconsin cranberry (Vaccinium macrocarpon Ait.) growing soils. These microorganisms also grew in basal salts media utilizing parathion as the sole carbon source. 14CO2 was produced only from [phenyl-14C]parathion, whereas [ethyl-14C]parathion-derived radiocarbon remained in the stale media of the soil-free cultures. Addition of 0.05% glucose to basal salts medium inhibited [phenyl-14C]parathion degradation, whereas the addition of 0.05% yeast extract to basal salts medium also inhibited microbiological degradation of the insecticide to 14CO2, but to a lesser extent. Aminoparathion and aminoparaoxon were formed only in basal salts medium with 0.05% yeast extract. Aerobic cultures produced more 14CO2 and less aminoparathion from [phenyl-14C]parathion than did anaerobic cultures. Aminoparathion was more abundant in cultures with inocula obtained from the 18- to 23-cm soil layer than with culture inocula obtained from the 0- to 5-cm soil layer under both aerobic and anaerobic conditions.