Lipidome comparison between planktonic and polyester-adhered microbes in municipal wastewater operations
Open Access
- Author:
- Pflumm, James
- Graduate Program:
- Agricultural and Biological Engineering
- Degree:
- Master of Science
- Document Type:
- Master Thesis
- Date of Defense:
- May 17, 2021
- Committee Members:
- Jeffrey M Catchmark, Thesis Advisor/Co-Advisor
Heather Elise Preisendanz, Committee Member
Paul Heinz Heinemann, Program Head/Chair
Joshua J Kellogg, Committee Member
Naomi S Altman, Committee Member - Keywords:
- bacteria
microbe
lipid
microplastic
plastic
polyester
PET
pollution
wastewater
sewage
lipidomic
omic - Abstract:
- Polyethylene terephthalate (polyester) microfibers are one form of microplastic. The rate of polyester microplastic (MP) pollution entering municipal wastewater currently exceeds the rate of degradation capable in Municipal Wastewater Treatment Facilities (MWTF). Residential laundry machine effluent has been estimated to contain 1,900 microfibers after one wash of a single polyester garment. Despite MWTFs removing up to 99% of microfiber particles, the remaining 1% of particles is significant. Beyond concerns regarding MP ingestion, MP’s potentially bind heavy metals and contaminants such as pesticides and pharmaceutical compounds, increasing the amount of toxic chemicals bioaccumulating in the food chain. Wastewater microbes potentially interact with MPs. Microbes possess lipid membranes interfacing with and responding to their environment. Prior work has demonstrated marine microbes can degrade oil pollution. Furthermore, quantifying the lipid composition of these microbial consortiums (MC) has been shown to provide a performance index of hydrocarbon degrading activity. This project investigates whether the lipids of wastewater microbes serve as biochemical indicators of microbial adhesion to a reproducible polyester-fiber test specimen, hereafter referred to as substrate. Detecting microbial lipid composition changes in response to this specific polymer substrate potentially benefits future microbiological and wastewater engineering research efforts to assess microbe-microplastic interactions under operationally constrained MWTF environmental conditions. I am not aware of prior published studies that have used lipidomic analysis to quantitatively characterize in-situ MWTF microbe interactions with plastic specimen substrates. The nature of this research will characterize the lipid composition of aerobic MWTF microbe-plastic interactions using liquid chromatography - mass spectrometry (LC-MS). The results of this dataset are not conclusive due to statistical sampling limitations of this pilot study. The contributions of the analysis documented herein are the methodological approach and lessons-learned for applying lipidomics to evaluate wastewater microbial interactions with plastic substrates of interest.