Patent ID: 6365397
Filing Date: 2002-04-02
Classification: A62D,B09C,C12N,Y10S

Abstract:
A biologically pure bacterial culture having an ability to degrade at least 10% of the methyl-t-butyl ether (MTBE) present at a concentration of 0.01 to 500 ppm aerobically within 70 hours to carbon dioxide without adding propane, butane, isopropanol, acetone and ethanol; wherein said biologically pure bacterial culture is isolated from a mixed bacterial culture obtained by a process comprising the steps of:adding an aqueous mixture comprising a first amount of activated sludge taken from a biotreater for treating wastewater in a Chemical Plant to a container, Adding a first portion of MTBE to said container to obtain a first mixture which contains from about 10 mg to about 500 mg of MTBE, incubating said first mixture at a temperature from about 10Â° C. to about 60Â° C., periodically adding additional amounts of the biosludge to said container, periodically withdrawing from the container from about 10% to about 70% of the supernatant medium followed by adding mineral solution to replace the supernatant withdrawn, and periodically adding MTBE to the container in an amount sufficient to maintain the concentration of MTBE in the mixture in the container at from about 10 mg to about 500 mg; wherein said mixed bacterial culture also has an ability to degrade methyl-t-butyl ether (MTBE) aerobically to carbon dioxide within 70 hours, wherein said biologically pure bacterial culture is obtained by a process comprising the steps of: (a) enhancing the isolation of said biologically pure bacterial culture from said mixed bacterial culture by a dilution enrichment process using MTBE and sterile nutrients-containing medium to obtain a dilute enrichment of said mixed culture, (b) transferring a portion of said dilute enrichment of said mixed culture from (a) to a sterile container comprising nutrients and solidifying agent, (c) incubating said container from (b) above to obtain colonies of bacteria, (d) transferring a portion of a colony from (c) above to a container and incubating it in presence of sterile nutrients and MTBE for a period of time, and (e) repeating step (d) until one of the colonies degrades MTBE to carbon dioxide after said incubating step of (d) above.