Bioemulsifiers and Biodegradation of Environmental Pollutants in Soil.

Abstract : The effect of enhancement of biodegradation has been shown by application of a number of biosurfactants and bioemulsifiers in vitro. Among lipopeptides the highest activity has been found in experiments with 'open' form of lichenysin A. Lichenysin A itself and surfactin did not increase the biodestructive activity of microorganisms and moreover in most cases inhibited the PCB degradation. A new glucose lipid surfactant MM1 showed in several tests a very high bioavailability enhancement. In a number of experiments the alkane-induced proteins from Gram-negative strains and polysaccharides from bacilli strains appeared to be efficient PCB emulsifiers improving the biodegradation capabilities of several microbial strains. It should be noted that generally bioemulsifiers and biosurfactants act very specifically, i.e. dependingly on strain and amount of these compounds used in experiment. Experiments set up with soil samples did not get a clear answer whether bioemulsifiers could critically enhance the rates of biodegradation processes in situ. Only with glucose lipid MM1 the more-less detectable positive effect, i.e. approx. 12% increase of PCB degradation comparing to control has been found.