[Directed screening of bacteria--destructive agents of surface-active substances]

A procedure for detection of bacteria destructing cationic surface active substances (CSAS) was developed. The procedure is based on changing colour of pyrocatechin violet, an organic dye from geen-blue in the presence of a CSAS to red-brown in its absence. After application of pyrocatechin violet to bacterial macrocolonies grown on a synthetic medium with a CSAS as the only source of C red-brown zones developed around the colonies which was probably indicative of the CSAS biodestruction. 55 strains of bacteria destructing undecylpyridinium bromide, a CSAS were isolated from water of sewage purification plants. The study of their spectrum with respect to CSASs of different chemical structure revealed 6 bacterial strains capable of destructing all the nine test preparations. It was shown that biodestruction of the CSASs was associated with the long carbon chain and depended on the presence of the substitute in the aromatic ring and branching in the side chain. Therefore, the procedure provides screening of microbes destructing CSASs and may be used for rapid determination of biodestruction of CSASs with different chemical structures.