Submitted to: Phytochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 6, 2007
Publication Date: October 22, 2007
Citation: Molyneux, R.J., Lee, S.T., Gardner, D.R., Panter, K.E., James, L.F. 2007. Phytochemicals: The Good, the Bad, and the Ugly?. Phytochemistry.68(22-24):2973-2985. Interpretive Summary: This article describes some of the main plants responsible for poisoning of livestock in the United States and other parts of the world. Among these are the Western false hellebore, lupines, locoweeds and morning glories. Isolation and identification of the natural chemicals in these plants enables them to be tested for the specific way in which they produce the toxic effects. Although they are poisonous to animals if the levels are high enough, they can be used as drugs or provide leads for potential new drugs, when used at lower levels. Observations of plant toxicity to animals can therefore be useful for treatment of human or animal diseases.
Technical Abstract: Phytochemicals are constitutive metabolites that enable plants to overcome temporary or continuous threats integral to their environment, while also controlling essential functions of growth and reproduction. All of these roles are generally advantageous to the producing organisms but the inherent biological activity of such constituents often causes dramatic adverse consequences in other organisms that may be exposed to them. Nevertheless, such effects may be the essential indicator of desirable properties, such as therapeutic potential, especially when the mechanism of bioactivity can be delineated. Careful observation of cause and effect, followed by a coordinated approach to identify the responsible entities, has proved extremely fruitful in discovering new roles for phytochemical constituents. The process is illustrated by selected examples of plants poisonous to animals and include the steroidal alkaloid toxin of Veratrum californicum (Western false hellebore), piperidine alkaloids of Lupinus species (lupines), and polyhydroxy indolizidine, pyrrolizidine and nortropane alkaloids of Astragalus and Oxytropis species (locoweeds), Castanospermum australe (Moreton Bay chestnut) and Ipomoea species (morning glories).