Award Date


Degree Type


Degree Name

Master of Science in Biochemistry

First Committee Member

Ernesto Abel-Santos, Co-chair

Second Committee Member

Chulsung Bae, Co-chair

Third Committee Member

Bryan Spangelo

Graduate Faculty Representative

Helen Wing

Number of Pages



Olive trees are one of the most important fruit trees in the Mediterranean. Although not validated by research, olive leaves are traditionally believed to fight off fever and infections. It has been shown that olive leaf extracts possess antimicrobial activity. Olive leaf extracts contain polyphenols. One of the major phenolic compounds is oleuropein. Oleuropein and other polyphenols have been shown to exhibit antimicrobial activity. East Park Research (EPR) developed an extraction process that they claim does not alter the chemical composition of the olive leaves. The extract is known by the commercial name d-lenolate®. Studies have provided evidence that d-lenolate®, like other olive leaf extracts, has antimicrobial activity against different pathogens. However, the active antimicrobial compound(s) of d-lenolate® has not been identified. The purpose of this study was to purify the active compounds of d-lenolate® and evaluate their antimicrobial activity. Different chromatographic methods were used to fractionate d-lenolate®. Disk diffusion and growth inhibition tests were performed to test for antimicrobial activity. We found that fractions of d-lenolate® extracts devoid of oleuropein were significantly more active than purified oleuropein. Interestingly, compounds from extracts that possess antimicrobial activity based on our results were shown to lose the trait when purified. Whether the d-lenolate® extracts or purified compounds provide greater antimicrobial properties in this study is not conclusive. However, the data demonstrated that d-lenolate® extracts at 1 mg/ml do not possess 100% antimicrobial activity, but only delays the growth of Bacillus anthracis and Escherichia coli.


Anti-infective agents; Leaves; Naturopathy; Oleaceae; Plant extracts; polyphenols


Biochemistry | Biochemistry, Biophysics, and Structural Biology | Chemistry | Medicinal-Pharmaceutical Chemistry

File Format


Degree Grantor

University of Nevada, Las Vegas




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