The Dirt on Antibiotics at the University of Dayton


The Dirt on Antibiotics at the University of Dayton



Michelle Lynn Borchers


This poster reflects research conducted as part of a course project designed to give students experience in the research process.



Antibiotics have become a problem as their overuse has led to pathogens resisting the effect of antibiotics. This is an important health matter as once effective antibiotics no longer work to cure some illnesses. The Small World Initiative and the Tiny Earth Network function to discover potential antibiotics in nature by isolating bacteria from soil samples in the environment and testing them against ESKAPE pathogens. The goal of this research is to help support the Small World Initiative by testing soil for the presence of naturally occurring antibiotics on the University of Dayton’s campus. A sample of soil was collected from a backyard on campus grounds and tested against ESKAPE pathogen safe relatives Enterococcus faecium and Enterococcus raffinosus. Antibacterial effects can be quantified by measuring the zones of inhibition on the agar plates. Lab techniques such as aseptic technique, serial dilution, master plates, and spread plates were used to isolate the pure bacterial colonies that showed antibacterial effects on the pathogens. Gram staining and biochemical testing were performed to try to identify the bacterial isolates. The biochemical tests include: catalase, hemolysis, triple sugar iron, mannitol salt agar, MacConkey agar, citrate, gelatinase, and motility. The antibiotic producing chemicals of the pure colonies were then extracted and tested with eukaryotic cells. The findings will help contribute to the mission of the Small World Initiative and the Tiny Earth Network.

Publication Date


Project Designation

Course Project

Primary Advisor

Erica Marie Rinehart, Yvonne Y. Sun

Primary Advisor's Department



Stander Symposium project

The Dirt on Antibiotics at the University of Dayton