Biodegradation of dimethylsilanediol in soils

The biodegradation potential of [C-14]dimethylsilanediol, the monomer unit of polydimethylsiloxane, in soils was investigated. Dimethylsilanediol was found to Re biodegraded in ail of the tested soils, as monitored by the production of (OC2)-O-14. When 2-propanol was added to the soil as a carbon source in addition to [C-14]dimethylsilanediol, the production of (C2O)-C-14, increased. A method for the selection of primary substrates that support cometabolic degradation of a target compound was developed, By this method, the activity observed in the soils was successfully transferred to liquid culture. A fungus, Fusarium oxysporum Schlechtendahl, and a bacterium, an Arthrobacter species, were isolated from two different soils, and both microorganisms were able to cometabolize [C-14]dimethylsilanediol to (CO2)-C-14 in liquid culture. In addition, the Arthrobacter sp. that was isolated grew on dimethylsulfone, and we believe that this is the first reported instance of microorganism using dimethylsulfone as its primary carbon source. Precious evidence has shown that polydimethylsiloxane is hydrolyzed in soil to the monomer, dimethylsilanediol. Now, biodegradation of dimethylsilanediol in soil has been demonstrated.