This presentation details the ongoing work for my LUROP fellowship: isolation and characterization of microbes essential to anaerobic digestion. While our work was stalled due to COVID-19, we detailed the progress we have made so far this semester as well as our future directions in this poster

Mcdonald, Brennan

English

Loyola eCommons

Isolation of Microbes Essential to Anaerobic DigestionBrennan McDonald and Greg Palmer, Ph.D.School of Environmental Sustainability, Loyola University ChicagoIntroductionLiquid Cultures• After obtaining an individual colony from an isolation plate, liquid cultures will be grown in the same modified R2A media• After sufficient growth, a sample will be taken from the culture and mixed in equal volume with 50% glycerol• Sample cultures with a final concentration of 25% glycerol will be preserved in cryotubes at -80°CCreation of a Microbial Library• Once microbes have been identified and freezer stocks has been created, we will create a library detailing organisms present in AD and their respective roles• This library will serve as a guide for future student researchers at Loyola to studyCharacterizing Microbial Community Dynamics• While isolation experiments are ongoing, we will also use 16S rRNA metagenomic analysis to characterize entire microbial communities undergoing AD in the lab• Key constituents determined by consistent presence in 16S rRNA community profiles will be identified and sought in isolation experiments • Key constituents can be used as pro-biotic interventions when small-scale AD reactors fail Anaerobic Digestion• Anaerobic Digestion is carried out by a diverse community of microorganisms• Characterizing these microorganisms and their respective functions in anaerobic digestion is the focus of the research projectFigure 3: Photographs of dilution plates (top row) and isolate plates (bottom2 rows) with modified R2A agar. The first dilution plate was a 100-folddilution of MWRD sample, whereas the others were 1000-fold dilutions,explaining lower colony count on those plates. Both the dilution plates andisolate plates are grown at room temperature until sufficient colony growthallowed for further streaking. All microbes pictured are aerobic or facultativeanaerobes, though in the future we will use specialized anaerobic chambersto grow obligate anaerobes from the MWRD sample as well.1. “Food Waste FAQs.” USDA, www.usda.gov/foodwaste/faqs.2. “Food Waste Initiatives: School of Environmental Sustainability.” Food Waste, Loyola University Chicago, www.luc.edu/sustainability/campus//recyclingwasteweek/foodwaste/.3. “How Does Anaerobic Digestion Work?” EPA: Biogas Recovery, Environmental Protection Agency, www.epa.gov/agstar/how-does-anaerobic-digestion-work.4. Keenleyside, Wendy. “Chapter 9: How Microbes Grow.” Figure 9.18 Microbiology: Canadian Edition, Creative Commons.Food Waste• In the United States, anywhere from 30-40% of our food supply goes to waste1• Food waste breaks down in landfills into carbon dioxide and methane, dangerous greenhouse gasses• Loyola has several initiatives to reduce food waste2• Composting in many areas of Lake Shore Campus• Food Recovery Network• Aerobic digester at Health Sciences Campus• Yet, Loyola still produces some food waste  on the LSC that should be redirected from landfillsMethodsReferencesAbstractAnaerobic digestion has the potential to eliminate thefood waste Loyola’s Lake Shore Campus sends to off-sitecomposting and landfills. It utilizes a diverse microbialcommunity to degrade the waste into useful outputs likenutrient-rich fertilizer and natural gas (methane). In orderto run efficiently, its community of microbes must becarefully maintained, especially on small scales like wewould utilize on campus. Isolating and characterizingthese microbes and their roles in this process could allowfuture researchers at Loyola to maximize the ability of ananaerobic digester to reduce Loyola’s food waste. Thegoal of this project is to begin the creation of a library ofAD microbes that can be used to produce a model ADsystem in the lab. Impacted by COVID-19, this project isongoing and will continue into Summer and Fall 2021.Isolation• Samples from a Metropolitan Water Reclamation District (MWRD) anaerobic digester were serially diluted and plated on modified R2A agar• Colonies were picked from dilution plates and streaked for isolationFigure 2: Overview diagram of the serial dilution process4Characterization• Analysis of colony morphology• Gram-staining• Phase contrast microscopy• 16S rRNA PCR using universal primers for molecular characterizationFigure 1: An overview of anaerobic digestion’s possible inputs as well as various uses for the products made3Anticipated Next StepsConclusion• Food waste will continue to be a problem for the foreseeable future• Anaerobic digestion could be a viable solution to reducing food waste here on the Lake Shore Campus• AD could also be explored in other smaller scale settings but will require monitoring, interventions • Creation of the microbial library would facilitate anaerobic digestion at Loyola, biological interventions• The library will also facilitate future student research on the AD process and its feasibilityProgressFigure 4: Photograph of an example 2mL cryotube to beused for storing library cultures

Isolation of Microbes Essential to Anaerobic Digestion

https://ecommons.luc.edu/cgi/viewcontent.cgi?article=1504&context=ures

Isolation of Microbes Essential to Anaerobic Digestion

Abstract

Similar works

Full text

Available Versions

Loyola eCommons