Alkaloids are the secondary metabolites of plants. Despite being biomolecules, they are considered as waste materials to plants.
The uses of alkaloids are based on their toxic effects on the body like a change in body’s physiology when administered.
But, some of these toxic effects are used to restore health by administering in the right doses.
However, excess doses are definitely poisonous and harmful to man.
Chemically they are nitrogen containing compound and are alkaline in nature.
They are also less soluble in water and can be found in different plant parts like leaves, stems, bark, roots, etc.
5 Uses of alkaloids
- As medicines.
- As Euphoric & addicting drugs
- As pesticides or insect repellents.
- For research and scientific study.
- To catch animals.
- In plants
Used in medicine
| Sl. No | Alkaloid | Medical Uses | Plant source |
|---|---|---|---|
| 1 | Vincristine | For cancer treatment | Vinca rosea (Catharanthus roseus) |
| 2 | Codeine | Cough remedy | Opium poppy |
| 3 | Quinine | Anti-malarial drug | Cinchona officinalis tree bark |
| 4 | Ephedrine | For treatment of blood pressure | Ephedra |
| 5 | Ergot (ergotamine) | Migraine relief | Ergot |
| 6 | Reserpine | Anti-hypertensive | Rauwolfia |
- Alkaloids have many pharmacological uses in health care.
- They act as life-saving drugs in some serious disorders like cancer, blood pressure, etc.
- Atropine, a derivative of belladonna, is used in the treatment of muscle spasms, while scopolamine is useful to inhibit secretions.
- Morphine, a derivative of opium alkaloid, is used for severe pain relief.
Euphoric & addicting drugs
- Many psychotropic substances like marijuana, cannabis, and opium sort of substances are alkaloids.
- They have been used since the ancient period as instruments for mental excitement and euphoria.
- However, they are considered as harmful as per modern medicine.
- They were in full-fledged use by kings and common for fun and as part of recreation.
- Even now, many people consume them by procuring them illegally.
Insect repellents and pesticides.
- As mentioned earlier, these alkaloids are toxic in nature.
- They are toxic in varying concentrations.
- Alkaloid pyrethrin is used as an insect repellent in mosquito coils, mosquito repellents, and even in agriculture.
- Luckily enough, at such concentrations, these insecticides are less toxic to humans but affect mosquitoes to leave the vicinity.
For research and scientific study
- Due to their specific effects on the body, they are used in research and scientific study.
- For example, atropine, an alkaloid, can cause dilation of the pupil.
- To test if a new substance is having similar effects or opposite effects, it is compared with atropine.
- So here, atropine is used as a standard for comparison in research for bioassays.
To catch animals like elephants
- Heavy animals, like elephants, were captured by making them immovable.
- For this, the hunters use arrow poison ( D-tubocurarine), which is applied to the arrow’s point and shot at the animal.
- When the arrow gets stuck to the animal, the alkaloid (D-TC) will enter the muscle and cause paralysis.
- This is a short-term action and is reversible. These immovable animals get trapped and transported. The same can be used for deer, wild animals, etc.
Benefits to plants
- Besides the above, alkaloids are also beneficial to the plants producing them. They are waste products of body metabolism.
- They are excreted through leaves, fruits, etc. and are toxic and bitter in nature, so they help the plant from being grazed by animals.
- Thus these alkaloids save the trees and plants from being eaten (grazing) by cattle.