- Alkaloids are basic nitrogenous plant compounds with pronounced physiological effects in humans and animals. They contain a heterocyclic nitrogen ring derived from amino acids.
- Common alkaloids include atropine, reserpine, and ephedrine. Atropine is an anticholinergic that causes dilated pupils and dry mouth. Reserpine lowers blood pressure by depleting catecholamines. Ephedrine acts as a bronchodilator and stimulant.
- Alkaloids are tested for using Dragendorff's, Mayer's, Hager's or Wagner's reagents, which form precipitates. They are classified based on their chemical structure, such as phenylalkylamines,