American University
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Analysis of the major constituents in St. John's Wort and Ephedra

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posted on 2023-08-04, 16:09 authored by Felicia Binion Williams

The Dietary Supplement Health and Education Act of 1994 established a formal definition of a "dietary supplement" using several criteria. Dietary supplements are products made of one or more nutrients, such as vitamins, minerals and proteins. They are intended to supplement the diet. Today many consumers use supplements without evaluating the product or considering the potential side effects. The supplement industry has increased sales into the billion of dollars in the last ten years. Liquid chromatography with ultra violet/visible, fluorescence, and mass spectrometry detection were used to measure the potentially active constituents in St. John's Wort. Additionally, measurements were carried out with spectrophotometry at 590 nm. St. John's Wort is used by consumers who have mild to moderate depression. Many clinical studies have been performed in the United States and abroad and the results are not conclusive. Four analytes are considered to possess pharmacological activity: the naphthodianthrones pseudohypericin and hypericin and the phloroglucinols hyperforin and adhyperforin. This project concentrated on measuring the naphthodianthrones because label claims are based on the level of total dianthrones and not phloroglucinols. Additionally, six alkaloids in Ephedra containing Ma Huang SRM samples were measured using liquid chromatography with two modes of detection: ultraviolet and mass spectrometry. Ephedra has six analytes which possess pharmacological activity: norephedrine and norpseudoephedrine, pseudoephedrine and ephedrine and methylephedrine and methylpseudoephedrine. Norpseudoephedrine is regulated by Drug Enforcement Agency, which is a precursor to elicit drugs. Many of the products containing Ephedra analytes are diet products and substances used to boost energy levels. The levels of the analytes vary significantly from product to product and can have severe or even deadly consequences if taken. Much research is needed for the analysis of dietary supplements. Initial studies should be performed on the plant material at various times of the year to assess the levels of potentially active analytes. Also, extraction studies are important to obtain the best method for maximum recovery of the analytes of interest. It is possible that the extraction technique could vary from plant source to finished product and an alternative technique may be needed.







Thesis (Ph.D.)--American University, 2003.


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