ABSTRACT
Biodegradation, in particular, provides a major route for the removal of contaminants from the environment. Chemical toxicity, on the other hand, may affect the biodegradation processes and the operation of food chains in aquatic environments. Most organic molecules that are naturally synthesized by living matter may also be degraded, in turn, by microorganism. Microbial action is one of the major factors responsible for the degradation of contaminants in aquatic environments; thus, bacterial biomass has been considered as an important parameter in the design of the biodegradation models. In the biodegradation study, it is more convenient to consider the microorganisms as the catalyst and the organic pollutants as the substrates. Understanding of basic biodegradation processes is useful for making sensible predictions about the possible behavior of lipophiles in aquatic environments. The biodegradation of a test compound by sewage microorganisms is generally reflected by a decrease in the concentrations of organic carbon in the medium.
