Un-related to : Lesser Celandine [a plant with similar name]. Greater Celandine belongs to the Poppy Family, whereas Lesser Celandine to the Buttercup Family. Their only other commonality is the colour of the flower, an orange-juice yellow colour; with about eight petals Lesser Celandine has twice the number of petals than does Greater Celandine.

A yellowish or reddish latex will ooze from broken stems, containing several noxious substances. The latex was used to treat warts; the alkaloids it contains are virucidal. Extracts from the plant have, in the past, been used in medicine for a panoply of conditions, including jaundice, hepatitis, ringworm, eczema and eye conditions.

Greater Celandine possesses a number of alkaloids belonging to the Protopine group, namely Chelerythrine, Chelidonine, Sanguinarine, Berberine and Coptisine, all depicted below. Barberry contains a number of other protopine alkaloids, including Berberine.

ISOQUINOLINE ALKALOIDS

All parts of the plant are highly poisonous including the latex. Greater Celandine contains the poisons isoquinoline alkaloids chelidonine, chelerythrine, Sanguinarine, coptisine and berberine and other benzyl isoquinoline alkaloids.

Chelidonine inhibits mitosis and is cytotoxic. Ingestion of the plant results in a burning sensation in the mouth and throat, followed by nausea, vomiting, sedation, narcosis, low pulse rate and finally cardiac arrest.

Sanguinarine is also found in Opium Poppy. If ingested, dropsy may result. On contact with skin Sanguarine will kill cells leaving a bleeding wound and a huge black scab of necrotic tissue similar to acid or alkali burns. Greater Celandine has been used commercially in wart removal preparations. Sanguinarine is used in some tooth-pastes and mouth rinses for its anti-plaque activity, but is no longer considered safe for prolonged use. Sanguinarine binds to certain proteins and exhibits anti-fungal, anti-bacterial and anti-inflammatory properties. It also inhibits adenosine triphospase, ATP. Despite its name, containing 'sanguin', meaning dark-red, Sanguinarine is colourless, but the salts of Sanguinarine are indeed red, and it is partly responsible (the other part responsible are the yellow coloured Berberine alkaloids) for the orange colouring in the roots of Bloodroot (Sanguinaria canadensis), a non-native plant with white flowers planted in the UK as a garden plant. [To eliminate confusion, Greater Celandine itself is sometimes referred to as 'Bloodroot' - but your Author has checked possible confusion in the literature: both plants do indeed also contain Sanguinarine]. Sanguinarine is the most toxic component of Greater Celandine having an LD50 of only 18mg/kg of body weight.

Berberine is found in Barberry bushes (Genus Berberis) as well as a number of other plants, including Greater Celandine. It is bright yellow, and was once used as a yellow dye to dye leather, wool and wood. It fluoresces strongly yellow under ultraviolet light, and is thus used in histology for staining heparin in mast cells. It is effective against some fungal infections and leishmaniasis, a parasitic worm. It may be effective in preventing diabetes in those with glycaemia (not to be confused with glaucoma, an eye problem) for it lowers both elevated blood glucose levels and blood cholesterol.

Coptisine is very bitter substance found mainly in Goldthread, a Chinese plant used in Chinese herbal medicine to treat digestive disturbances caused by errant bacteria. Coptisine is present mainly in the roots of Greater Celandine.

If the plant or latex is ingested, berberine, chelidonine and sanguinarine intercalate with DNA inhibiting a number of proteolytic enzymes and polymerases; this accounts for its cytotoxic, anti-viral and anti-bacterial properties. The latex also contains the phytocystatin called Chelidostatin, which is a cysteine protease inhibitor. Ingestion of large doses of the latex results in a burning sensation in the mouth, vomiting, paralysis, dizziness, arrhythmia, slow pulse, hypotension and finally collapse.

CHELIDONIC ACID

Four of the above protoberberine and benzophenanthridine alkaloids have a positively charged nitrogen atom and they form complexes with Chelidonic Acid which results in the bright yellow colour of the latex. Chelidonic Acid is named after the scientific name for Greater Celandine (Chelidonium majus) and is chemically similar to the Meconic Acid present in Welsh Poppy, which also belongs to the Poppy Family.