Effect of co-metabolism on biodegradation of hydroxamic acid

The biodegradation of four kinds of hydroxamic acids with and without the existence of co-metabolism substrates were studied and compared in the paper. The biodegradation rates of benzohydroxamic acid, salicylic hydroxamic acid, N-hydroxy-phthalimide and H₂O₅ (2-hydroxy-3-naphthalene A hydroxamic acid) respectively were 68.2%, 78.3%, 56.5%, 7.2% after shaking culture at 25°C for 96 h in the sole substrate condition. The biodegradation rates of the four kinds of hydroxamic acid were increased to 86.3%, 90.1%, 79.5%, 10.8% with the presence of additional carbon source glucose (120 mg/L), and with the coexistence of carbon source (120 mg/L glucose) and nitrogen source (80 mg/L peptone), the biodegradation rates respectively increased to 99.3%, 99.8%, 95.2%, 23.7%. The experimental results showed that the presence of co-metabolism substrates significantly improved the biodegradability of benzohydroxamic acid, salicylic hydroxamic acid, N-hydroxy-phthalimide, and slightly improved that of H₂O₅.