Investigation into qNMR for use in natural products research

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Wilson Brooks (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Nicholas Oberlies

Abstract: Natural products research constantly has to deal with problems of analysis. Therefore, orthogonal techniques are extremely valuable when analyzing complex mixtures that are often seen in fungal extracts. Analysis of results of fungal fermentation experiments can influence the design of further experimentation. Earlier results can then expedite the process of analysis. Quantitative nuclear magnetic resonance spectroscopy (qNMR) offers analysis of complex mixtures at early stages and with several benefits over some more common methods of quantitation, including ultraviolet absorption spectroscopy (UV) and mass spectrometry (MS). Several experiments were conducted to construct a methodology for use in analysis of natural products samples. A broadly applicable method was sought for use in both pure and complex mixtures. An externally calibrated method was used to quantify the solvent peak inside of a single batch of DMSO-d6, which was used repeatedly to quantify interesting analytes. Thereby, a method was constructed that did not require contamination with calibrant for quantification of analyte signals. The method was implemented to measure the biosynthetic yield of griseofulvin and dechlorogriseofulvin from three fungal isolates. One isolate, a Xylaria sp. coded MSX648662, was found to biosynthesize griseofulvin in the greatest yield, 149 ± 8 mg per fermentation, and was selected for further supply experiments.

Additional Information

Publication
Thesis
Language: English
Date: 2016
Keywords
Filamentous Fungi, Natural Products, qNMR, Quantitation, Secondary Metabolites
Subjects
Natural products $x Research
Nuclear magnetic resonance spectroscopy
Chemistry, Analytic $x Quantitative

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