Date of Project


Document Type

Honors Thesis

School Name

College of Arts and Sciences



Major Advisor

Dr. Amanda Krzysiak


Natural products have served as powerful therapeutics against pathogenic bacteria since the golden age of antibiotics of the mid-20th century. In the United States, antibiotics are a key component of modern medicine and are one of the top written prescriptions every year. However, overuse and misuse of antibiotics has led to an increasing frequency of antibiotic-resistant infections. These infections are difficult and expensive to treat, often resulting in increased length of illness, hospital stays, and mortality rates. This demonstrates a clear need for novel antibiotics in for modern medicine. Murrubium vulgare (white horehound) is a shrub found in the Appalachia region that has been used in herbal medicine to treat many pulmonary aliments as an expectorant or tonic. Previous studies of this plant and its commercial products have indicated that it may contain antioxidant and antibacterial properties. The aim of this study is to determine if whole leaf extracts of M. vulgare contain antimicrobial properties. Five different plants were sampled for this project. The leaves were dried and extracted in 95% ethanol in a 1:10 (m/v) ratio. The solvent was removed using a rotavapor at 60°C and hot plate evaporation. The crude product was left in a desiccator until constant weight was achieved. The crude samples were analyzed to characterize the different classes of natural products present. The crude extracts were dissolved in 5% DMSO at different concentrations. The disk diffusion assay was applied to determine the antimicrobial activity. The results indicated that M. vulgare did not have antimicrobial activity.