Specialized bacterial strains for the removal of dichloromethane from industrial waste

Dichloromethane utilized by an anaerobic mixed culture: acetogenesis and methanogenesis

“…strain DM2, 2.5 mkat/kg of protein; strain DMll, 9 mkat/ kg of protein (Scholtz et al 1988). We thus suspect that improved rates of anaerobic degradation of DCM in wastes can be attained, because Gfilli & Leisinger's (1985) fluidized bed effectively depended on the activity of strain DM2, which has the same specific degradation rate for DCM as our anaerobic mixed culture. On the other hand, growth of the anaerobic mixed culture in DCMsalts medium is subject to inhibition by components in the groundwater.…”

“…(kg charcoal), is much lower than G~lli & Leisinger's (1985) aerobic fluidized bed (1.6 g DCM/h.1): they were using a salts medium saturated with DCM (as the sole organic component) in a technically complex model system which produced large amounts of biomass (about 12 g dry weight/mol DCM) at 30 ° C, and they attained an efficiency of 99.9%. The efficiency of our fixed-bed reactor for the removal of DCM from contaminated groundwater (> 99.99%, Table 1) rivals that of Gfilli & Leisinger (1985) and has the advantages that (1) no (pure) oxygen must be pumped into the system, (2) no fluidized bed must be maintained and, (3) very little biomass must be disposed of. We calculate that 45kg dry weight of biomass was produced from DCM during three years operation, an amount that did not significantly alter the fluid dynamics of a system with llm 3 of interstitial space.…”

“…Gfilli & Leisinger (1985) used an aerobic fluidized-bed reactor to treat model aqueous waste with an efficiency of > 99.9%. An aerobic immersion percolating filter system, in contrast, lost > 80% DCM to the atmosphere (Winkelbauer & Kohler 1989).…”

Albibacter methylovorans gen. nov., sp. nov., a novel aerobic, facultatively autotrophic and methylotrophic bacterium that utilizes dichloromethane.

“…Both aerobic methylotrophic bacteria (Leisinger et al, 1994) and a strictly anaerobic acetogenic bacterium (Ma$ gli et al, 1998) growing with DCM as the sole carbon and energy source have been isolated. A set of 14 aerobic DCM-utilizing bacteria (strains DM1-DM14) has previously been isolated from soils and waters contaminated with the compound (Brunner et al, 1980 ;Stucki et al, 1981 ;Gaelli & Leisinger, 1985 ;Scholtz et Abbreviations : DCM, dichloromethane ; GSH, reduced glutathione ; PMS, phenazine methosulfate ; RuBP, ribulose bisphosphate.…”

Anaerobic dechlorination of tetrachloromethane and 1,2-dichloroethane to degradable products by pure cultures of Desulfobacterium sp. and Methanobacterium sp.

“…A few of these compounds, generally with a low level of chlorination, are subject to aerobic degradation [ [2][3][4][5][6][7] or transformation [8-10; see also 11], and some of these degradative capacities can be applied to waste or water treatment [5,12,13]. But for the most part, the highly chlorinated solvents are subject only to anaerobic transformation [14][15][16][17][18][19][20][21][22].…”