Proposed Mechanism Explaining Seasonal Biological Foaming in Activated Sludge Systems; Foam-Causing Bacteria Specialize in Consuming Lipids

The validity of this mechanism was first tested by studying the relationship between lipase (lipid hydrolyzing enzyme) activity, temperature, and foam occurrences. Lipase activity was found to be higher in foaming plants and very sensitive to temperature, substantiating the role of temperature in seasonal biological foaming. The validity of the assumption that the mycolata specialize in consuming lipids, which are slowly degradable substrates, was also tested. To this end, a model capable the predicting the dynamics of the cellular rRNA pool was developed and validated. This model predicted that the diurnal rRNA profile of a population consuming slowly degradable substrates remains stable throughout the day. Conversely, the diurnal rRNA profile of a population consuming readily degradable substrates varies due to variations in COD loading rates. Thus, the modeling exercise linked the molecular identification of microbial populations and the determination of their ecological function. Diurnal rRNA profiles were then measured for bacterial populations found in full-scale activated sludge wastewater treatment plants, and the experiment support the assumption that mycolata specialize in consuming lipids.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Civl and Environmental Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Frigon, Dominic

Contributors dc:contributor

• Raskin, Lutgarde

• Biology, Microbiology

Language dc:language

eng

Identifier

(MiAaPQ)AAI3182266

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/83259