What are alkaloids?
Alkaloids is are naturally occurring organic compounds that contain nitrogen and are primarily found in plants . They have diverse and important physiological effects on humans and animals. (Encyclopedia Britannica) But first, we need to understand what an organic compounds is.
Lets start with a simple everyday drink like water, which is made up of hydrogen and oxygen atoms. Water does not have carbon atoms, so it’s not an organic compound.There are a few exceptions of compounds with carbon that are classified as inorganic, namely carbon dioxide, carbonates and cyanide salts.
Sugar on the other hand is made up of carbon, hydrogen and oxygen atoms. Because sugar has carbon atoms in it, it’s an organic compound. An organic compound contains carbon as well as hydrogen, bonded, covalently (C-H). Examples of organic compounds are carbohydrates, protein, fats and oils and nucleic acids like DNA.
So alkaloids are organic compounds, that contain nitrogen. They are mostly found in plants, in the leaves, seeds, roots and fruits, and tend to have a bitter taste. They are very diverse. More than 10,000 alkaloids have been isolated from plants. (Introduction to Alkaloids)
If you drink coffee or tea on a daily basis, then you definitely know what an alkaloid is, because both coffee, tea and cocoa contain caffeine (C8H10N4O2) which is one of the most consumed alkaloids.
Well known alkaloids include:
Caffeine: this is one of the most consumed alkaloids, found in coffee, tea, cocoa. It stimulates the central nervous system in small doses.
Nicotine: this is the principle alkaloid in the tobacco plant (Solanum tabacum). Tobacco belongs to Tomato family, Solanaceae. Nicotine is the principal alkaloid in cigarettes. If you’re a smoker then you certainly experience this alkaloid on a daily basis,
Strychnine: this is a poisonous alkaloid from the seeds of nux vomica tree (Strychnos nux-vomica).
Quinine: a drug obtained from the bark of Cinchona spp. It’s used in treating Malaria. These plants belong to the coffee family, Rubiaceae.
Ephedrine: an alkaloid used as a decongestant drug. It’s obtained from Chinese species, Ephedra sinica (Ephedraceae).
Morphine: a narcotic analgesic drug ( a drug that relieves pain, selectively), obtained from Poppy (Papaver somniferum)
The plant families, rich in alkaloids include:
- Poppy family (Papaveraceae)
- Buttercup family (Ranunculaceae)
- Tomato, tobacco and potato family (Solanaceae)
- The monocotyledous family, Amaryllidaceae (Amaryllidaceae alkaloids)
- Coffee family, Rubiaceae
- Sunflower family, Asteraceae (Compositae)
- Orange family, Rutaceae
- Oleander family, Apocynaceae