Document Type

Thesis

Date of Degree Completion

Spring 2019

Degree Name

Master of Science (MS)

Department

Chemistry

Committee Chair

Gil Belofsky

Second Committee Member

Levente Fabry-Asztalos

Third Committee Member

JoAnn Peters

Abstract

Multidrug resistance has increased since the introduction of drugs used to prevent growth and kill microorganisms in a host. This has caused a worldwide search to discover new drugs effective against microorganisms. Mechanisms of drug resistance include, but are not limited to, the production of biofilms and efflux pumps. Efflux pumps prevent antimicrobial drugs from reaching their biological target, so the coordinated use of efflux pump inhibitors and antimicrobial drugs has been identified as a potential treatment for multidrug-resistant microorganisms. The secondary metabolites of Dalea mollis and Dalea albiflora were tested against multidrug-resistant (MDR) and engineered strains of the fungi Candida glabrata and Saccharomyces cerevisiae. Two known pterocarpans, two known flavanones, and an isoflavonoid were isolated and identified from D. mollis. Two new flavanones (albifloran A 9 and albifloran B 10), one known pterocarpan, and three known flavanones were isolated and identified from D. albiflora. Initial results revealed that the components of D. mollis were inactive against the fungal strains tested, but components of the roots of D. albiflora did show activity. VLC fractions three and four of D. albiflora inhibited the growth of the S. cerevisiae expression host and S. cerevisiae overexpressing Snq2 with minimal inhibitory concentrations (MIC) of 42 μg/mL and 87 μg/mL, respectively. VLC fraction four inhibited the growth of C. glabrata overexpressing Snq2 with an MIC of 167 μg/mL.

Share

COinS