Quantitative method for the measurement of three benzofuran ketones in rayless goldenrod (Isocoma pluriflora) and white snakeroot (Ageratina altissima) by high-performance liquid chromatography (HPLC).

White snakeroot ( Ageratina altissima ) and rayless goldenrod ( Isocoma pluriflora ) can cause "trembles" and "milk sickness" in livestock and humans, respectively. Tremetol, a complex mixture of sterols and derivatives of methyl ketone benzofuran has been extracted from white snakeroot and rayless goldenrod and is reported to be the toxic substance in plant material. In this study, the three major benzofuran ketones, tremetone, dehydrotremetone, and 3-oxyangeloyl-tremetone, were isolated from rayless goldenrod. Using these compounds as standards, a quantitative high-performance liquid chromatography (HPLC) method was developed to measure these compounds in white snakeroot and rayless goldenrod. Concentrations of tremetone, dehydrotremetone, and 3-oxyangeloyl-tremetone were found to vary considerably among the different white snakeroot and rayless goldenrod plant collections. Differences in concentrations of tremetone, dehydrotremetone, and 3-oxyangeloyl-tremetone in white snakeroot and rayless goldenrod plants may explain the historical sporadic and unpredictable toxicity of these plants to livestock and humans.