Study On Isolationand Conditions Of Bacterial Strain Capableto Metabolizehigh Concentrations Of Formaldehyde

Many kinds of decoration materials, coatings and adhesives havebeen used frequently in recent years. These substances release manyvolatile organic compounds (VOCs) which are harmful to human health,formaldehyde is one of the main important indoor pollutants, which isbeen deeply concerned more and more. The indoor formaldehydepollution has seriously affected people's health. Thus it has become animportant social issue to control and treat the indoor formaldehydepollution.The aim of this research was to isolate a strain can metabolizeformaldehyde, then investigate the formaldehyde degradation conditionsand find the optimal conditions that the strain metabolize formaldehyde.Finally the reactor simulation of formaldehyde biodegradation wasintroduced; it will provide basic study for treatment technology about the indoor formaldehyde pollution.One bacterial strain capable to degrade and metabolize formaldehydeas a sole carbon source was isolated from soil. Based on the results ofstandard morphological identification, physiological and biochemicalcharacters, and 16S rDNA sequence analysis, the strain was identified asPseudomonas putida.After single factor tests and orthogonal tests, the optimal conditionsfor formaldehyde degradation were determined as the follows: peptone1.2g/L, KH2PO4 4 g/L, K2HPO4 3 g/L, MgSO4·7H2O 0.2 g/L, trace elementssolution 0.1 mL/L, temperature 30℃, pH8.Under the optimal conditions, the strain tolerance of originalformaldehyde concentration was up to 6 g/L and 86% of formaldehydewas consumed after 54 h. It completely consumed 5 g/L formaldehydeafter 46 h and degraded 100% of 4 g/L formaldehyde after 35 h. Inaddition, the investigation about the reactor simulation is successful,formaldehyde can volatilize by heating, then the gas is dissolved inmedium which contain formaldehyde metabolize strain; formaldehydecan be utilized continuously by strain.