Digitalis purpurea nectar within. The fruit is a capsule which splits open at maturity to release the numerous tiny 0.1-0.2 mm seeds. The three subspecies of "Digitalis purpurea" are: Due to the presence of the cardiac glycoside digitoxin, the leaves, flowers and seeds of this plant are all poisonous to humans and some animals and can be fatal if ingested. Extracted from the leaves, this same compound, whose clinical use was pioneered by William Withering, is used as a medication for heart failure. He recognized it "reduced dropsy", increased urine flow and had a powerful effect on the heart. Unlike the purified
Plant physiology plants produce a vast array of chemical compounds with unique properties which they use to cope with their environment. Pigments are used by plants to absorb or detect light, and are extracted by humans for use in dyes. Other plant products may be used for the manufacture of commercially important rubber or biofuel. Perhaps the most celebrated compounds from plants are those with pharmacological activity, such as salicylic acid from which aspirin is made, morphine, and digoxin. Drug companies spend billions of dollars each year researching plant compounds for potential medicinal benefits. Plants require some nutrients, such as carbon and