Date of Award
Dr. Ruth Plymale
Dr. Sara Hubbard
Dr. Doug Sonheim
Many bacteria have become resistant to commonly used antibiotics because of antibiotic use in people and animals. Therefore, new antibiotics are needed that will inhibit these resistant bacteria. Bacteria found in soil are a likely source for new antibiotics because of the limited available nutrients found in the soil. We isolated soil bacteria and screened them for antibiotic production against Staphylococcus epidermidids. Methanol extracts were made from entire agar plates of the soil bacteria that inhibited S. epidermidis. These extracts were spotted on a lawn of Staphylococcus aureus; growth inhibition was measured to comfirm that the extracts contained the antimicrobial compounds. The confirmed inhibitory extracts were then separated by thin-layer chromatography using a chloroform-methanol mobile phase. The separated compounds were individually suspended in methanol and spotted onto S. epidermidis or S. aureus to assess inhibitory ability. Whole cell metabolite extracts isolated from four soil bacteria were found to inhibit both S. epidermidis and S. aureus. Four TLC-separated metabolite compounds, one from Hargis and three from Jackson, were found to inhibit S. epidermidis. These compounds will be futher assessed for viability as new therapeutically relevant antibiotic treatments.
Hughes, Heidi, "Discovering New Antibiotics: Bacterial Extracts Separated by Thin-Layer Chromatography Inhibit the Growth of Staphylococcus" (2016). Honors Theses. 219.