Anaerobic environments, biodegradable

Secondary alkanesulfonates are easily biodegradable under aerobic conditions but are less so in an anaerobic environment, a feature common to all sulfonates with the stable carbon-sulfur bond. The recent discussions on anaerobic biodegradation [103] should be put into perspective since in the sewage or deposition path a temporary anaerobic step quickly gives way to a stage where natural conditions, which are aerobic, prevail. Thus, anaerobic biodegradation... 

Burland SM, EA Edwards (1999) Anaerobic benzene biodegradation linked to nitrate reduction. Appl Environ Microbiol 65 529-533. 

Anaerobic Environments. Because the initial attack of the LAS molecule is oxidative, LAS does not biodegrade under anaerobic conditions (19). Therefore concerns are sometimes expressed that LAS may accumulate in deep anaerobic sediment layers, where it will not biodegrade further. However, given the high rate of LAS removal during sewage treatment combined with in-stream degradation, it is unlikely that LAS sediment accumulation will occur unless there is rapid deposition into an anaerobic environment. 

Dyestuffs in general, and azo dyes in particular, are likely to undergo. substantial primary biodegradation in an anaerobic environment through reductive cleavage of azo bonds into aromatic amines. Lipophilic aromatic... 

Biodegradation significant degradation on anaerobic environment with k = 0.5 d 1 (Tabak etal. 1981 Mills etal. 1982)... 

Biodegradability - Metabolix PHA offer hydrolytic stability under normal service conditions but when exposed to microbial organisms naturally present they break down enzymatically in soil, composting, waste treatment processes, river water and marine environments. They also rapidly decompose to carbon dioxide and water and will degrade in anaerobic environments, unlike some other biodegradable polymers. 

Hostetler F. and Kvenvolden K. (2002) Forensic implications of spilled oil biodegradation in anaerobic environments. Geol. Soc. Am. Abstr. Prog., Denver, Colorado, October, 2002. 

Abramowicz DA. 1995. Aerobic and anaerobic PCB biodegradation in the environment. Environ Health Perspect Suppl 103(5) 97-99. 

No information on the release of 1,1,2-trichloroethane to soil was found in the available literature. It is anticipated that process residues and sludge containing this chemical may be landfilled (Jackson et al. 1984). In an experiment designed to simulate the anaerobic conditions for biodegradation in landfills, 1,1,2-trichloroethane was found to be a biodegradation product of 1,1,2,2-tetrachloroethane (Hallen et al. 1986). Therefore 1,1,2-trichloroethane may be produced in landfills or other anaerobic environments (e.g. groundwater) that have been contaminated with 1,1,2,2-tetrachloroethane. 

Chitin that occurs in the exoskeleton of invertebrates (such as mollusks and arthropods) is composed of N-acetyl-D-glucosamine residues linked by 1,4 /3-Iinkages. A partially deacetylated chitin also occurs naturally as chit-osan. Microbial species responsible for the breakdown of chitin and chitosan have not been comprehensively studied. Micro-organisms found in a variety of environments (for instance, in fresh water [29], marine sediment [30], garden soil [31], and even anaerobic environments [32]) are known to produce chitinases and/or chitosanases. Table 56.1 shows a listing of some reported species of bacteria and fungi that yield these enzymes and are therefore, able to biodegrade these polysaccharides. 

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