Part 6: Phytochemistry—Alkaloids

Alkaloids are thought to be the largest class of naturally occurring compounds  produced by plants that typically contain one or more nitrogen atom as part of their structure. In general, alkaloids are known as defensive molecules and are extremely effective at warding off dangerous herbivores. Usually these molecules are bitter to the taste (to prevent the herbivore from continuing to eat) or are poisonous. Because the structure of these molecules contains nitrogen components, they are able to work as agonists or antagonists in the neurological systems of animals. This means they can take the place of neurotransmitters in the body and interfere with their normal course of action, causing toxic consequences. Although dangerous to some organisms, many unique and recreational applications for alkaloids have been discovered. Examples of alkaloids are ephedrine, caffeine, cocaine, morphine, and nicotine.