Hydroperoxides of Unsaturated Fatty Acid Methyl Esters from Kenyan Plant, Vernonia auriculifera

Various plants have been used in traditional medicine in Kenya for many years for treating a broad range of human diseases. The mode of application depends on the nature and form of plant components. In some cases, fresh leaves, stems or roots are boiled or soaked in water or they may be burned, roasted or pounded prior to oral or hypodermical adminitstation. To confirm the existence or formation of toxic components in such plants, thirty eight different medicinal plants from Kenya were examined by brine shrimp toxicity bioassay. Only one species, Vernonia auriculifera was found to have lethal toxicity. The toxic component was isolated as a mixture and found to be very unstable. The potassium iodide coloration test, oxidative activity toward triphenylphosphine requisite for obtaining triphenylphosphine oxide and 1H-NMR spectrum indicated this component to possibly be a mixture of several hydroperoxides of unsaturated fatty acid methyl esters.