Abstract From Young Scientist : Tetrahdroxysqualene from Rhus taitensis shows antimycobacterial activity against Mycobacterium tuberculosis

By Jeffrey C. Noro,†‡ Louis R. Barrows,§ Osia G. Gideon, Chris M. Ireland, ‡ Michael Koch,§ Teatulohi Matainaho,† Pius Piskaut, Christopher D. Pond,§ Tim S. Bugni‡*

Department of Medicinal Chemistry, University of Utah, 30 S. 2000 E., RM 307, Salt Lake City, UT 84112, USA
Department of Pharmacology and Toxicology, University of Utah, 30 S. 2000 E., RM 201, Salt Lake City, UT 84112, USA
School of Medicine and Health Sciences, University of Papua New Guinea, PO Box 5623, Boroko, NCD, Papua New Guinea
School of Natural and Physical Sciences, University of Papua New Guinea, PO Box 320, Boroko, NCD, Papua New Guinea


† School of Medicine and Health Science, University of Papua New Guinea
‡Department of Medicinal Chemistry, University of Utah
§Department of Pharmacology and Toxicology, University of Utah
School of Natural and Physical Science, University of Papua New Guinea

Presenter: Mr. Jeffrey Noro

Abstract:
Tuberculosis, caused by the bacterial pathogen Mycobacterium tuberculosis, has become a major global health threat, especially in developing nations. TB therapy requires long treatment regimens and patient compliance is difficult. Failure of patients to comply with therapy has led to the emergence of multi drug resistant TB (MDRTB) and extremely drug resistant TB (XDRTB). There is an ever-growing need for new therapeutics for treatment of TB, especially for HIV/TB patients.

Over the past decades, natural products have played an important role as sources of secondary metabolites with potential as lead compounds for drug discovery.
In our search for new therapeutic leads against TB, we isolated a new triterpene from the plant Rhus taitensis collected in Papua New Guinea. Tetrahydroxysqualene was isolated using bioassay-guided fractionation of the methanolic extract of R. taitensis leaves and twigs. The structure of tetrahydroxysqualene was elucidated on the basis of HRESIMS and 1D and 2D NMR spectra. Tetrahydroxysqualene exhibited anti–tuberculosis activity with an EC50 of 2.7 g/mL while showing little cytotoxicity.