Repetitive extragenic palindromic PCR (REP-PCR) as a method used for bulking process detection in activated sludge

摘要

Bulking of activated sludge is a world widely prevalent problem and can lead to loss of bio-oxidation, further deterioration of effluent quality, and even to a complete breakdown of the entire treatment process. Most common rea sons of bulking are bacterial community changes, especially excessive growth of filamentous bacte ria or excess of biopolymers on surface of non filamentous microbes. Because of complex nature of the bulking phenomenon, the successful bulk ing control strategy finding is still a very important need awaiting new options and advices. The repet itive extragenic palindromic PCR (REP-PCR) fingerprinting method has been applied to dis tinguish bacterial community in non-bulking and bulking activated sludge. The characteristic REP PCR fingerprinting patterns, using the Ward's clustering method, have been analyzed to deter mine homology/similarity relation between par ticular non-bulking and bulking sludge sampling. The received clustering results were in high con cordance with activated sludge typing done based on physicochemical sludge analysis. The choice and application of molecular typing method in sludge analysis will depend upon the needs, skill level, and resources of the laboratory. The pro posed REP-PCR method and statistical analysis of fingerprinting patterns seems to be simple, rapid, and effective methods to show differences between population in non-bulking and bulking activated sludge. It is easy to implement, and it may be useful for routinely activated sludge mon itoring as well as may be helpful in early detection of bulking process.