Skip to main content


The full text article is not available for purchase.

The publisher only permits individual articles to be downloaded by subscribers.

or click here to sign up for a free trial


Methanol is a widely employed carbon and electron source for denitrification favored over alternate commercial carbon and electron sources such as ethanol or acetate since it is relatively cheaper. Although biokinetic parameters for methylotrophic denitrification in activated sludge have been previously reported (Purtschert and Gujer 1999), relatively little is known on the abundance and diversity of methylotrophic organisms in activated sludge. Current and previous methods for estimating methylotrophic denitrifying populations in activated sludge have relied chiefly upon modeling and mass balance approaches. In the absence of accurate knowledge on identity and abundance of methylotrophic bacteria in activated sludge, reactor design, monitoring and modeling efforts to optimize methylotrophic denitrification are severely handicapped.

Iin this study, we applied a realtively novel technique, stable isotope probing of 13C labeled DNA to specifically identify the microorganisms that took up and metabolized methanol in an anoxic sequencing batch denitfiying reactor. Based on SIP, the major microorganisms were most closely related to Methyloversatilis spp. And Hyphomicrobium spp. Based on batch denitrification assays, methylotrophic nitrite reduction biokinetics were significantly lower than nitrate reduction biokinetics despite complete nitrate and nitrite removal in the parent SBR. However, little nitrite self-inhibition was observed in extant batch denitrification assays. Measured average yield coefficients for nitrite and nitrate reduction were statistically similar but were significantly lower than thermodynamics based estimates.

Finally, as the terminal electron acceptor was changed from nitrate to nitrite (keeping the methanol dose the same), the specific denitrification rates on both nitrate and nitrite decreased significantly.

Document Type: Research Article


Publication date: January 1, 2007

More about this publication?
  • Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed.

    WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.
  • Subscribe to this Title
  • Membership Information
  • About WEF Proceedings
  • WEFTEC Conference Information
  • Ingenta Connect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more