Anthraquinones

Anthracene (three benzene rings joined together) at each apex of the

central ring is a carbonyl group (carbone double bonded oxygen)

which is the quinone part.

Senna

• Usual occur as glycosides– sennosides; O-glycosides– aloins; C-glycosides– cascarosides; C,O-glycosides

– in dried herb always present as anthraquinones, because anthrones are unstable in free state.

Cascara Bark

• Used as laxatives

• go to large bowel, where bacterial action formes anthrone aglycones, which are the true active forms.

• Laxative effect is local, systemic absorption is limited;

• modification of intestinal motility

• accumulation of fluid in the intestinal lumen.

Rheum palmatum

• Leading to peristaltic movements, partly due to release of prostaglandin.

• Accumulation of fluid in colonic lumen also has the laxative effect.– Anthrones; stimulate active chloride secretion

into the lumen, balanced by an increase in sodium and water flow, the prostaglandins and the alteration of calcium transport may play a role here to

• In lower laxative dosies that produce normal motion, the effects on motility are apparent in high doses electroyle secretion and diarrhoea will predomeinate

• habituation and adverse effect due to electrolyte loss associated with the use of high doses. Chronic laxative abuse lead to raised aldosterone levels due the electrolye sloss, which diminishes there effectiveness.,

• higher doses empty a larger portion of the colon, leading to natural absence of defeacation of the nest day, leading to reuse and high dose.

Aloe vera

• Hypericin, pseudohypericin; dianthrones (structurally related to antrhquinones) and other anthraquinones such as rhein, emodin.– antiviral activity

Rubia tinctorum• Anthraquinone glycosides lucidin and alizarin

– used as dye– used for prevention and treatment of kidney stones;

works as chelating agent with calcium, leading to significant reduction in the growth rate of kidney stones in animal models.

– Will colour urine pink, indicating that significant quantities of the anthraquinones are excreted in the urine, possibly dissolving stones.

Toxicology

• Rubia tinctorum; withdrawn due to concerns over mutagenicity and carcinogenicity, however longterm feeding to mice failed to lead to neoplastic lesions.

• Laxatives; mild abdominal pain, cramps• discoloration of urine, haemorrhoid congestion• overdose; diarrhoea, excessive loss of

electrolytes, esp. potassium.

Rubia tinctorum

• Abuse; habituation, however can restore normal function.

• Long term use can lead to melanosis, brown discoloration in colon, harmless, reversible.

• Contra Indications;– ileus– pregnancy, lactation (however systemic

absorption is unlikely), and several studies indicate no risk to foetus or pregnancy, or leading to affect infant via breast milk.

• Possible long term abuse not conclusive on colorectal cancer.

• Do not use long term.