Carbon dioxide anaerobic incubation

Biological. Complete microbial degradation to carbon dioxide was reported under anaerobic conditions by mixed or pure cultures. Under enzymatic conditions formaldehyde was the only product reported (Vogel et al., 1987). In a static-culture-flask screening test, methylene chloride (5 and 10 mg/L) was statically incubated in the dark at 25 °C with yeast extract and settled domestic wastewater inoculum. After 7 d, 100% biodegradation with rapid adaptation was observed (Tabak et al., 1981). 

In aerobic soils, aldicarb degraded rapidly (half-life = 7 d) releasing carbon dioxide. Mineralization half-lives for the incubation of aldicarb in aerobic and anaerobic soils were 20-361 and 223-1,130 d, respectively. At an application rate of 20 ppm, the half-lives for aldicarb in clay, silty clay loam, and fine sandy loam were 9, 7, and 12 d, respectively (Coppedge et al, 1967). Other soil metabolites may include acids, amides, and alcohols (Hartley and Kidd, 1987). 

Moore T. R. and Dalva M. (1997) Methane and carbon dioxide exchange potentials of peat soils on aerobic and anaerobic laboratory incubations. Soil Biol. Biochem. 29, 1157-1164. 

A stoichiometric amount (0.1 mM) each of enzyme-bound FAD and C-u-L-lysine (u = uniformly labelled) was incubated anaerobically until FAD was fully reduced. After deproteinization the reaction mixture was subjected to high voltage paper electrophoresis and paper chromatography. Most of the radioactivity appeared at the area corresponding to piperidine 2-carboxylic acid (a-keto-c-aminocaproic acid) (Figure 7), and a significant amount of carbon dioxide was not detected. When the reaction mixture was aerated to reoxidize FAD and then deproteinized, the radioactivity was also found at the position of piperidine 2-carboxylic acid. 

Halomethyl compounds are subdivided into monohalomethyls, which are alkylating agents, and polyhalomethyls, which must be metabolized to an ultimate species. Reductive dechlorination of carbon tetrachloride 353) to chloroform by rabbit liver microsomes parallels the concentration of cytochrome P-450 in the microsomes but requires anaerobic conditions and NADPH. The identification of hexachloroethane after incubation of NADPH-reduced microsomes with carbon tetrachloride is indicative of homolytic formation of the free radicals of chlorine and trichloromethyl and supports the hypothesis that such species initiate an autocatalytic peroxidation of lipid membranes that results in the observed hepatotoxicity. A similar scheme for radical formation and lipid destruction has been described by Reynolds and Moslen for halothane. In contrast to the reductive dechlorination of carbon tetrachloride, the metabolism of chloroform to carbon dioxide in vitro requires oxygen and produces carbonyl chloride (phosgene) as an intermediate. That this also... 

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