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Centaurium erythraea, centaury
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Centaurium erythraea, centaury DESCRIPTION Family: Gentianaceae
Part used: aerial parts
Centaurium erythraea Rafn. is a variable biennial or annual found throughout Europe, mainly on calcareous soils and dry grassy places, including sand dunes and chalky uplands (Gibbons & Brough 1992). There are about 14 species of Centaurium in Europe but there is disagreement over their identification and infraspecific hybrids occur which are also interfertile so the identity of local populations can be unclear (Tutin et al 1973). The Flora of Turkey (Davis 1978) gives five Centaurium species, including Centaurium erythraea. Smooth, erect stems (10–50 cm) arise from a basal rosette of smooth, oval, greyish-green leaves and bear opposite, narrow, smooth stem leaves with three veins. Small, tubular, pink flowers with five petals occur in summer in a branched inflorescence at the top of the stem. Many small seeds form in cylindrical capsules and the anthers coil after dehiscence.
Quality Collect when in flower (Bisset & Wichtl 2001). Bradley (2006) states that the greatest bitterness is in two esters of sweroside found in the flower ovary. Wild collection should be avoided as calcareous grassland is a priority habitat listed on the UK Biodiversity Action Plan (2009). This annual plant is a priority for cultivation, especially as Cullen (1775) states that plants are larger and more bitter when grown on fertile soil. Studies on the taxonomy of the Gentianaceae disagree (Meszáros et al 1996, Mansion & Struwe 2004) and there is debate on the number of species because of variation within species depending on environment. There is some hybridization between Centaurium erythraea and other species such as lesser centaury Centaurium pulchellum, which is a smaller annual with no basal rosette and fewer flowers often found on moist grassland near the sea, seaside centaury Centaurium littorale, which has distinctive narrow oblong leaves (Stace 1991) and is found in sandy turf and dunes, and perennial centaury Centaurium scilloides, which is distinguished by its procumbent habit with rounded, stalked leaves on the creeping stems, and is a rare plant found on cliff tops (Sterry 2006). Other species used: Centaurium uliginosum, Centaurium littorale, Centaurium pulchellum (Van der Sluis & Labadie 1981). Culpeper also refers to a yellow variety with larger, darker green leaves and the stem passing through the middle of the leaf. This could be yellow wort Blackstonia perfoliata, an annual (Stace 1991) that is locally common on calcareous grassland. Culpeper also refers to a white flowered species, which could be Centaurium tenuiflorum, an annual and similar to Centaurium pulchellum, which is usually pink but rarely white. Centaurium tenuiflorum and Centaurium scilloides were both listed as vulnerable in the UK in 1994 (UK Biodiversity Action Plan 2009). Centaurium erythraea is listed as vulnerable and Centaurium uliginosum is listed as endangered in the Czech Republic, and Centaurium erythraea is listed as threatened by wild collection in Hungary (Lange 1998).
LESSER CENTAURY, GREATER CENTAURY AND CHIRON, THE CENTAUR Dioscorides (III 7) describes lesser centaury with an angular stem over a span long, resembling St John’s wort or oregano, with flowers faintly purple like rose campion, small and longish leaves like rue, fruit like grains of wheat and a small useless bitter root. The use of comparisons is © 2009 Elsevier Ltd, Inc, BV DOI: 10.1016/B978-0-443-10344-5.00018-5
interesting: St John’s wort Hypericum perforatum also has a smooth stem with small opposite leaves and a branched flowerhead. This description can be taken as common centaury. The only discrepancy is that, as Fuchs comments, according to Dioscorides, it grows in marshy places whereas ‘everyone knows that with us it grows commonly in hard, dry, grassy fields and meadows’. Dioscorides uses the name centaury for two plants: the lesser centaury and the greater centaury (III 6), which is a metre tall with blue flowers, serrated walnut-like leaves and a substantial red root. It is probably a knapweed in
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Figure 13.1 Centaurium erythraea, centaury (near Fondi, Italy, July).
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Centaurium erythraea, centaury the genus Centaurea. Lesser means the smaller of the two related plants, and this monograph discusses the use of the lesser centaury, which is now called common centaury and remains in use today. The illustration given by Fuchs is of centaury (1980) and later authors such as Culpeper and Miller continue to refer to ‘the red ordinary small centaury’. The two plants are very distinguishable but this introduces the possibility of confusion between the two entries in subsequent herbals. The listing of two unrelated species is significant as centaury is one of the four panaceas ascribed by Pliny to Chiron, the centaur who is the archetype of healers (Bostock 1855). The four panaceas were Asclepion, Heracleon, Chironion and Centaurion, and Dawson (1949) gives Centaurion as Centaurea centaurium L. The association with Chiron, the centaur indicates the long usage of these plants and associates both with wound healing. For example, in the Iliad of Homer, which describes the Trojan War, Eurypylos says, ‘Cut the arrow out of my thigh … and put kind medicines on it, good ones, which they say you have been told of by Akhilleus, since Kheiron, most righteous of the Kentauroi, told him about them’ (Theoi Project 2008). Old ulcers that refused to heal were called Chironian, as if requiring Chiron himself to heal them (Dawson 1949). The connection is worth investigating as centaury was used by Chiron to treat what was ultimately his fatal wound, as he eventually died because of a wound that could not be healed. Chiron, the centaur ‘half like a horse, half a god’, was the son of Saturn (Cronos) and the nymph Philyra who was a daughter of Ocean. Chiron lived with his wife Chariclon in a cave on Mount Pelion in Greece and was the tutor of Asclepius, god of medicine, and reared Achilles (Dawson 1949). When Hercules was passing by on his labours in search of the Erymantian boar, Chiron was accidentally wounded by one of Hercules’ poisoned arrows. One version states that he was wounded in the knee by an arrow meant for other centaurs and Hercules applied a healing herb, and another version states that Chiron dropped the arrow on his left foot by mistake. The arrow was poisoned with the blood or gall of the Hydra, and this fulfilled the prophecy of Chiron’s daughter that he would long for death, although immortal, and his death would be caused by a serpent. Chiron was immortal and could not die, but was released from immortality by Prometheus, who offered himself to Zeus to be immortal in Chiron’s stead. The significance of these events as recounted by Ovid is heightened by the presence of Achilles, who mourns for his mentor, which links this archaic event with the events of the Trojan War (Brookes 1994). Brookes also comments that Ovid uses the word ‘foot’ rather than ‘hoof’ and notes the linkage with the eventual death of Achilles from an arrow-shot in the foot. He further notes a linkage with the eventual death of Hercules, who died on a pyre to escape the pain caused by a shirt sent by his wife Deianira. The
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shirt was smeared with the blood of the centaur Nessus, which was infected by the Hydra. Returning to the recommendations of the mortals, greater centaury has a large, red astringent root and, comparing the two entries in Dioscorides, the emphasis is more on wound healing for greater centaury than it is for common centaury, and common centaury may not be the wound herb of Chiron. However, it is also strongly recommended for use in wounds. Mattioli argues that the Arabic writers confounded lesser and greater centaury and thus the texts are unclear, but later texts also lack clarity. Some authors consider them together whereas others give two entries.
WOUND HEALING The initial advice of Dioscorides on centaury is unclear as he refers to the ‘small useless root’ of common centaury but then recommends the pounded root as a plaster for injuries, and to cleanse old ulcers to form a scar. Mattioli cites Galen as stating that the root of lesser centaury is ineffective but the aerial parts are most useful. Galen states that the bitter quality permeates them yet there is a little astringency, which makes it an ideal drying medicine without being harsh or stinging: ‘Therefore, large wounds are closed up by anointing of this fresh herb; and old ulcers which can hardly be induced to scar over, are scarred over by using it in the same way. Dried, it is put among the herbs with gluing and drying properties, those evidently which are destined by nature to heal sinuses and fistulas and soften old hardnesses, and to heal malignant ulcers’. Fuchs also cites Galen giving the same details, and the advice is repeated by Dodoens and in less detail by Gerard. Serapio writes similarly and advises common centaury for fistulas and indolent or deep ulcers either as the fresh plant or as the dried plant with emollient herbs. Ibn Sina describes the two centauries but does not distinguish in his recommendations. He states that centaury cleans fresh wounds and closes old ulcers, and that dried centaury is used in preparations for plasters for use in fistulas, including ‘lacrimal fistulas’. This last recommendation for use in fistulas is also made by Dodoens, who advises the powder of dried aerial parts. We find that Culpeper recommends the fresh herb bruised and applied to close up fresh wounds and for old ulcers and sores ‘perfectly to cure them both although they are hollow and fistulous’. Later recommendations are less specific: Miller suggests external use in fomentations against swellings and inflammations. Quincy refers to the fomentation as discutient, dispersing morbid matter, whereas Coffin refers to use of a strong tea in scrophula (see the discussion under figwort, Chapter 28) and longstanding ulcers without specifying whether it be drunk or applied.
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Figure 13.2 Centaurium erythraea, centaury.
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Centaurium erythraea, centaury Further external usages are explained by Dioscorides, who describes the preparation of juices from the aerial parts collected when in seed. The fresh herb is soaked for 5 days, boiled hard, strained and then boiled again until it reaches a honey-like consistency. Given the scarcity of centaury, and the difficulties of producing a sterile pre paration, then this preparation would present some challenges. Dioscorides recommends the juice for eye conditions, cleansing with honey ‘those elements that cast a shadow over the eyes’. This is repeated by Fuchs, citing Galen, and by Dodoens, Parkinson and Gerard. Another external recommendation that is hard to interpret is made by the Salernitan herbal, which recommends local application of the juice with leek juice for ‘worms in the ears’. This could be otitis external or Beck suggests ear wax. This is also repeated by Parkinson, who recommends the decoction dropped into the ears to remove ‘worms’. Culpeper repeats Parkinson and both recommend external usage for scabs, freckles and spreading scabs of the head. This is copied by Grieve and thus has been copied onto websites which give herbal information. The transmission of the texts is unclear and recommendations are not possible for this paragraph.
‘HIP AILMENTS’ AND MUSCULOSKELETAL CONDITIONS The herb is consistently recommended both for external usage and internal usage and it is not always apparent which is being recommended. First I will discuss external and internal usage for muscular pain and arthritis, and then move on to internal use as a bitter, which is the most common usage today. Dioscorides states that the decoction of the root is a suitable enema for hip ailments delivering blood and relief. Gunther (1933) gives this as ‘a fit glister (enema) for the Ischiaticall, draweth out blood and easing the pain’. Serapio writes that the decoction is useful as an enema to treat sciatica as it expels choleric humours. Turner uses the text of Dioscorides and states that ‘the broth is good for sciatica as it draweth the blood and easeth the pain’. Descriptions of hip pain sound more like osteoarthritis of the hip or septic arthritis than the use of the term sciatica today to describe pain extending from the hip down the leg. Fuchs, citing Galen, states that some pour the decoction on hip pains. Ibn Sina may shed more light on use in hip ailments as he advises centaury for muscle tears and the appearance of pus there. He advises use of an enema in sciatica, nerve pain and tears and that if blood comes out then this is beneficial. This version is more clear than in some authors and suggests that he means discharge of blood from the wound and thus cleansing of the wound. Gerard comments that although the ancient authors
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consider that centaury purges by stool, he has never found it so but has found it useful in sciatica. Some authors such as Dodoens suggest that blood in the stool is a useful result of treatment, which cannot be the case. Dioscorides also advises the juice for ‘ailments around the tendons’, which is given as diseases of the sinews by Turner and Dodoens. Mattioli, citing Galen, states that it is counted among those which heal rheumatic afflictions, for which those medicines are best which are strongly drying and somewhat astringent but not too sharp. Fuchs gives this slightly differently, specifying that centaury is useful in rheumatic afflictions where vehement drying and astringent qualities are needed without any sharpness. These recommendations are followed by Parkinson and Culpeper with the addition of ague and old joint pains; ‘with other things to dry up rheum’. The area around the joints was visualized as being stretched because of the flow of the phlegmatic humour into the area, and thus herbs were needed to dry up or promote the flow of this humour (Culpeper et al 1655). This links with the descriptions of temperament: centaury is described as hot and dry in the third degree by Ibn Sina, and hot and dry in the second degree by Dodoens and Culpeper. Bauhin states that the pills are useful for those with sciatica, defects of the nerves and gout. Riviere (Culpeper et al 1655) discusses gout and its causes. The word ‘gout’ was used for gout as we understand it today, and also for pain in other joints, including sciatica or hip gout. Centaury continued to be used for gout and Grieve notes its use in the once famous Portland powder, which was a recipe purchased and published by the Duke of Portland (Thomson 1815).The powder contained equal portions of aerial parts of centaury, germander Teucrium chamaedrys, ground pine Ajuga chaemapitys and the root of gentian Gentiana lutea and birthwort Aristolochia species. Two of these ingredients are no longer used: Aristolochia species have been banned because of an association with kidney failure (MHRA 2003) and Teucrium chamaedrys has been associated with cases of serious hepatotoxicity linked with the use of slimming teas (Larrey et al 1992). The dose of Portland powder was 1 drachm (4 g) to be taken every morning, fasting for 3 months; then 3 4 dram (3 g) for a further 3 months and so on for a year; then 1 2 dram (2 g) on alternate mornings for a further year. Buchanan and Kean (1987), however, cite Heberden as saying that this remedy rose too fast and fell too far. There is a linkage between external usage in old wounds, in sciatica and disease associated with the tendons and with internal use for gout. Other bitter tonics such as bogbean Menyanthes trifoliata continue to be used internally in musculoskeletal pain. Fernie (1897) refers to use of the hot infusion of centaury for muscular rheumatism. Quincy suggests that some say it is febrifuge, especially in tertian fevers and Hill states that ‘country people cure agues with it’. Again this usage appears to be based on the recommendation of Galen, who described it as evacuating
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THE WESTERN HERBAL TRADITION the choleric humour from the body. Galen is cited by Dalechamps as linking use of the decoction for tertian fever with the action of expelling bile via the rectum. The French version of Mattioli adds to the discussion of centaury by proposing that the decoction helps greatly the tertian agues, for it makes bile leave downwards, and thus it is called febrifuge, ‘chasse-fièvre’.
BEST BITTER AND VISCOUS HUMOURS Having looked at external application and usage for painful joints, we come to the main current usage of centaury, which is as a bitter. Employment as a bitter tonic with an influence on bile flow appears to have been continuous since the time of Dioscorides. This usage is continued into more modern texts and one gains the impression that authors are writing from experience. For example, Coffin states ‘for many years we have used it with great success where the digestive organs have been seriously impaired’. This is repeated in current texts such as Hoffmann who refers to it as indicated primarily in anorexia especially if associated with liver weakness, indigestion and any condition where a sluggish digestion is involved. My personal experience is that it is an excellently well-tolerated herb and useful in poor appetite in the elderly and in small children. Interestingly, however, we still have Dioscorides to thank for the original recommendation ‘the root boiled and drunk, dispels through the bowels matter that is bilious and thick’. Mesue, cited by Serapio, advises 2 drachms (8 g) in decoction to purge thick phlegm. Ibn Sina recommends centaury for obstructions of the liver and as a remedy for a hardened spleen both as a drink and applied topically, which recommendations are repeated by various authors including Culpeper. Ibn Sina advises 6 g as a decoction for colic and states that sometimes the decoction cleanses mucous and unripe humours as well as yellow bile. Mattioli states that Galen wrote an entire treatise on centaury dedicated to the town of Papia and argues that it removes bile and phlegm, which the greater centaury does not. Fuchs also cites Galen at length and advises centaury to purge bilious and thick humours and resolve obstructions of the liver. Fuchs also cites Pliny as recommending 1 drachm (4 g) in 1 hemina (about 270 mL) of water with a little salt and vinegar to purge the bowels and draw down the bile. Turner states that it drives out choler and gross humours via the belly, and Dodoens advises it boiled in water or wine for this purpose but links this usage with sciatica. Parkinson states that it thins the blood and humours and purges choleric and green humours. Culpeper states that it purges choleric and gross humours,
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and is especially good for the blood. He recommends a decoction of aerial parts for colic and jaundice; it ‘opens obstructions of liver, gall and spleen’ as well as being useful for gout and cramps in joints. Quincy claims that it ‘discusses and absturges viscous humours’ and increases discharge by stool or urine but also helps to thin these humours for evacuation through the skin. Quincy recommends a decoction or infusion in wine. Macer argues that centaury ‘dries up the wild humours of a man’s spleen’ which has been ‘often proved’. Fuchs cites Galen as stating that it is good for those whose nerves are affected. Mattioli says that there are those who recommend it for those affected by nerves, in that it empties out and dries harmlessly those things which are full. Dalechamps gives this as ‘those with nervous afflictions or who are full of humours’. Bauhin suggests that advice for use of centaury in nerve disease such as apoplexy, paralysis and epilepsy is based on the action of centaury to ‘pull things away from the intestine’. Reading these recommendations, one thinks of the importance that Fuchs gives to pictures as representing the form and thus the nature of the plant. Words can sometimes express so little about the actions and quality of a herb. The advice of Macer makes one think of the pure, clean bitter taste of centaury, as if it would regulate flow and thus purify the spirit. Modern authors such as Menzies-Trull and Wood recommend centaury in depression associated with digestive disturbance and Wood gives the recommendation of Fernie (1897) for use in ‘languid digestion’ with heartburn after food. He also discusses the connection between this action and the use of the Bach flower essence of centaury for courage and to help the person to speak out. Pelikan describes centaury as ‘open and friendly yet reticent’. He refers to the medicinal function of bitters as to ‘make the ether body inclined to receive the astral body’, hence the etheric aspect of the organs serving metabolism will be suffused with astral influence, allowing a vigorous and healthy response to the ingested food. ‘The right appetites will then arise, the fluid organism will be toned and conscious awareness strengthened’. Returning to the physical, usage as an anthelmintic is not mentioned by Dioscorides but it is recommended by Ibn Sina and then the Salernitan herbal for ‘worms in the belly.’ Apuleius advises the herb crushed in vinegar for worms and this appears in Turner, Dalechamps, Parkinson and Culpeper. Parkinson, copied by Culpeper, states that he has found it useful. A continuing theme is that centaury is both bitter, thus creating an appetite, and a pleasant stomachic in indigestion. Culpeper claims that ‘the herb is so safe you cannot fail in the using of it’. Other writers note its agreeable and pleasant nature including Miller, Quincy, Cullen, Coffin, Robinson, Fox, Fernie, Hool and Grieve. Some authors, such as Gerard and Hill emphasize a powerful action on the liver and use of the powder in jaundice.
Centaurium erythraea, centaury Pelikan links this dual action to centaury as it develops more in the direction of stem and stalk than the more usually flower-centred gentians and will therefore work on the ‘rhythmic element in metabolism’. It is thus useful, he says, for ‘lack of appetite, poor gastric function, gastritis, heartburn, to stimulate hepatic and biliary activity and in cases of jaundice’. According to Zeylstra (1985a), centaury is used for heartburn and hyperacidity and he cites Kniepp as advising it for heartburn and to relieve the stomach of superfluous winds. Zeylstra (1985b) advocates taking bitters at least 30 minutes before meals and sipped in water for maximum effect. The Myddfai also emphasize use as a bitter stomachic, advising centaury for poor appetite, pain in the cardiac area (possibly heartburn) and pain extending to the shoulder, which could be referred pain from the gall bladder. My experience of using it as a tincture is that it is a bitter tonic that is effective without being too strong. Coffin recommends it alone, with other bitters or with raspberry Rubus idaeus in weak and debilitated patients where the digestive organs are seriously impaired. Hool recommends a tonic for the delicate or elderly: centaury 1 2 oz, raspberry Rubus idaeus 1 2 oz, infuse in 1 pint. Take a wineglassful (60 mL) four times a day. The British Herbal Pharmacopoiea recommends it as a carminative in dyspepsia, in anorexia and in children with gastric or hepatic weakness. Schulz et al (1998) and Hoffmann list it in their discussion of bitters and note its use in anorexia. Menzies-Trull suggests that it is also useful when there is oversecretion of bile. There are other bitters, and for ecological reasons this herb is not the first choice. However, it is of particular service in people with low energy, including elderly people with poor appetite and my experience is that is very effective and well tolerated. It is also the herb of choice for children, who sometimes combine poor appetite with susceptibility to infections. The authors refer to its use in painful joints and when the nerves have been upset, and this leads to a recommendation for use where the person is debilitated due to illness. An example of this is traditional usage in Scotland of an infusion as a tonic, particularly to improve the appetite in tuberculosis sufferers (Beith 1995). I might include centaury where there are aches and pains associated with chronic fatigue syndrome or fibromyalgia.
EMMENAGOGUE? The expulsive action of centaury on humours leads us to another action of the herb. Hoffmann includes centaury in his list of bitters that are also emmenagogue but the evidence for this statement needs some discussion. Both greater centaury and centaury are referred to as ‘drawing down the menses’ when used as a pessary. Riddle (1991) cites Oribasius, writing in the 4th century AD, as listing the
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following herbs for an antifertility action: beaten wormwood, pennyroyal, century plant, thyme, rue and others. As discussed in other monographs, the meaning of the word emmenagogue varies and can refer to abortifacients, herbs useful if the menstrual cycle is irregular and herbs traditionally used in the management of labour. Riddle (1992) discusses the many problems in interpreting texts. He argues that the word emmenagogue was used as a code and that herbs were used as contraceptives throughout history, in particular to avoid conception. The evidence on centaury is particularly difficult to interpret as two dissimilar herbs are discussed by the authors. With regard to greater centaury, Discorides states that ‘the root draws down the menses and the embryos/ foetuses when whittled, shaped like a pessary and applied to the uterus. The juice accomplishes the same’. With regard to lesser centaury, Dioscorides states that the juice, probably of aerial parts, ‘induces menstruation and abortion when used as a pessary’. Ibn Sina affirms that centaury stimulates urine and the menses, and expels the foetus. The Salernitan herbal states that it provokes menstruation as a poultice, or pessary. Turner advises that the juice ‘laid in with wool in the natural place, bringeth down womens sickness’, and Dodoens suggests use of a pessary for the same purpose and to expel the dead child. Parkinson refers to centaury as emmenagogue, to expel the foetus and ease period pains. Culpeper advises it for the pain associated with a still birth. To conclude, it could be argued that this suggests caution in use of a tea in pregnancy (see Recommendations on safety).
ALEXIPHARMIC PANACEA Finally, centaury is recommended as an alexipharmic, for example by Quincy. Alexipharmics are substances considered to protect the heart against poison, in particular after venomous bites. Apulieus proposes the herb crushed in vinegar to dispel the poison after a bite of a viper. Parkinson and Culpeper recommend 1 drachm (4 g) of powder for snakebite in wine, and Culpeper adds that is ‘wonderful good against the biting and poisons of an adder’. This links with a use as an antidote to poisons. Pliny refers to the Gauls using it against poisoning. The healing of inflammation from wounds and protection against wounds or snake bites is an ancient theme in the use of centaury as it was an ingredient in Mithridatum. This remedy is based on a formula sent by Zopyrus, physician to King Ptolemy of Egypt, to Mithridates VI (d. 63 BC), King of Pontus, which is an area west from Trabzon on the southern shore of the Black Sea. The formula contains 20 aromatic plants, including ginger, myrrh and centaury, of which 15 remained in the formula of 36 ingredients proposed by Celsus (Norton 2006). This is advocated for protection against poisons in food or venomous bites, and
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THE WESTERN HERBAL TRADITION ‘serious conditions’ by Celsus (25 BC-50 AD), a Roman doctor who wrote a substantial work on medicine, which was published in 1478 and was thus one of the first printed books (Spivack 1991). This formula was used as the basis of Theriac by Galen and remained in pharmacopoeias to the 17th century. Discrepancies and substitutions in the Theraic of Mithridates were one of the spurs to the production of the Pharmacopoeia Londinensis, published in Latin in 1618 (Griffin 2004). Other compound medicines such as Theriac Londinensis, London treacle, were also used to resist pestilence (Woolley 2004). Pestilence, in the days of infectious disease, plague, contaminated water and badly stored food was a much broader concept than snake bites, so alexipharmic remedies can be seen as preventing disease in a wider sense. Although transmission by bacteria had not been identified, the contagious nature of many diseases was well-known (Nutton 1983). Jerusalem balsam was another panacea used in Europe that was formulated at the Franciscan monastery of St Saviour in Jerusalem at the beginning of the 17th century (Moussaieffa et al 2005). Centaury was included in one formula of 40 ingredients found in Venice which dates from the early 18th century. Given the earlier discussion of internal and external use of centaury, it is interesting that the same remedy was used both externally on wounds, including gunshot wounds and fistulas, and also daily in small doses in food to resist infectious diseases. This recalls Ibn Sina and Apuleius, who both advise that internal usage will heal wounds. Apuleius advises a decoction in water boiled down to a third part. Centaury continues to be used today in Turkey for chronic inflamed wounds, either as a tea of aerial parts or as a salve made with olive oil (Berkan et al 1991). Brooke (1992), maybe in a reference back to the story of Chiron, Hercules and Achilles, argues that centaury is useful to face the day with courage, to stand up for yourself, and to drink ‘before a long journey where trials of strength are to be attempted’. The alexipharmic action in treating wounds and acute infection could be used again in current herbal medicine in treatment in acute situations, and the concept of an antidote taken regularly in small doses of herbal medicines to protect against infection remains a potent symbol of the power of herbs to preserve health.
RECOMMENDATIONS • External usage for chronic wounds is recommended by all the authors and the detailed advice of Galen suggests experience with this herb. Although this usage has not been continued to the present day, the authors do give it prominence and it could be reintroduced as long as the source of the plant material is sustainable. • Internal usage for arthritis, muscular and joint pain can be recommended, particularly associated with depression, fibromyalgia or where the person is recovering from illness. • The British Herbal Pharmacopoiea recommends it as a bitter, aromatic and stomachic for use in anorexia, dyspepsia and in children with gastric or hepatic weakness. One has to broaden this recommendation to usage wherever there is poor appetite, also in conditions such as irritable bowel syndrome where a mild but effective medicine is required. Given the emphasis by the authors on the action of centaury to drive out choleric humours, phlegm and unripe humours, then it may have a more dynamic action on the bowels as a tea than in the more common modern form of a tincture. • The authors recommend a decoction of aerial parts in flower. A decoction for use in acute situations such as wounds, bites or stings could include centaury alongside other herbs such as yarrow Achillea millefolium and comfrey leaf Symphytum officinale. • A small dose in a medicine to prevent reoccurrence of a chronic condition such as irritable bowel could be seen as harking back to the recommendation as an alexipharmic. Dosage: the British Herbal Pharmacopoeia recommends 2–4 g three times a day of dried flowering aerial parts. Ibn Sina gives the dose of 6 g for colic and uterine pains, which corresponds, somewhat astonishingly, with the daily dose given by Commission E (Blumenthal 1998). The doses used by herbalists as medicines are often very small, for example 10–15 mL weekly of a 1 : 5 tincture, which is equivalent to 400 mg daily.
CONSTITUENTS Reviews: Barnes et al (2007), Bisset & Wichtl (2001), Bradley (2006), Mills (2003), Williamson (2003).
Secoiridoid glycosides Secoiridoid glycosides are bitter compounds that are characteristic of Gentianaceae, and representatives of three types are found: swertiamarin; sweroside and two related compounds, gentiopicroside and gentioflavoside. Secoiridoid glycosides
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are the main compounds found in centaury but derivatives of the iridoid glycoside loganic acid and intermediate compounds (secologanol and centauroside) are also found (Jensen & Schripsema 2002). Particularly bitter esters of secoirioid glycosides accumulate in the seeds (Van der Sluis & Labadie 1981). Total 1.2%: swertiamarin, sweroside (Kumarasamy et al 2003a), gentiopicroside (Kumarasamy et al 2003b). Swertiamarin 0.5–8.8%, gentiopicroside, no sweroside (wild, five populations, Bulgaria) (Nikolova-Damyanova & Handjieva 1996). Swertiamarin (predominant), gentioflavoside, dihydrocornin (Do et al 1987). Monoterpene iridoid alkaloids gentianine, gentianidine, gentioflavine were derived from iridoid glycosides (Handjieva et al 1991) and anaerobic incubation of swertiamarine with intestinal bacteria showed that three main metabolites were produced, including erythrocentaurin and gentianine (El-Sedawy et al 1989).
Sterols Beta-sitosterol, stigmasterol, campesterol, brassicasterol, delta 7 stigmastenol (aerial parts) (Aquino et al 1985).
Phenolic acids Hydroxycinnamic acids: p-coumaric acid, ferulic acid, sinapic acid (Valentão et al 2001).
Coumarins Isocoumarin (wild, Portugal) (Valentão et al 2003).
Flavonoids Flavone: kaempferol (Valentão et al 2001).
Xanthones Methoxylated xanthones: eustomin, demethyleustomin (wild, Morocco) (Schimmer & Mauthner 1996). Methoxylated xanthones: six, including eustomin; tetraoxygenated xanthones (12 samples) (Valentão et al 2002).
RECOMMENDATIONS ON SAFETY 1. Do not use centaury as a tea during pregnancy. 2. The uses of either centaury as a pessary is obviously
not advisable. In contrast, the doses used by herbalists as medicines are often very small and the conclusion has to be that centaury Centaurium erythraea is safe in pregnancy used thus.
REFERENCES Aquino R, Behar I, Garzarella P, et al 1985 Chemical composition and biological properties of Erythraea centaurium Rafn. Bollettino della Societa Italiana di biologia sperimentale 61:165–169. Barnes J, Anderson LA, Phillipson JD, 2007 Herbal medicines, 3rd edn. Pharmaceutical Press, London. Beith M 1995 Healing threads. Polygon, Edinburgh. Berkan T, Ustünes L, Lermioglu F, et al 1991 Antiinflammatory, analgesic and antipyretic effects of an aqueous extract of Erythraea centaurium. Planta Medica 57:34–37. Bisset NG, Wichtl M (eds) 2001 Herbal drugs and phytopharmaceuticals, 2nd edn. Medpharm, Stuttgart.
Blumenthal M (ed) 1998 The complete German Commission E monographs. American Botanical Council, Texas. Bostock J 1855 The natural history. Pliny the Elder. Taylor and Francis, London. Online. Available: http:// www.perseus.tufts.edu/hopper 26 Mar 09. Bradley PR 2006 British herbal compendium, vol 2. British Herbal Medicine Association, Bournemouth. Brooke E 1992 A woman’s book of herbs. The Women’s Press, London. Brookes I 1994 The death of Chiron: Ovid, Fasti 5.379– 4414. The Classical Quarterly 44:444–450. Buchanan WW, Kean WF 1987 William Heberden the Elder (1710–1801): the compleat physician and sometime rheumatologist. Clinical Rheumatology 6:251–263. Cullen W 1775 Lectures on the materia medica, as Delivered in the University of Edinburgh. Philadelphia, Robert Bell Online. Available: http//books.google.co.uk 24 Mar 09. Culpeper N, Cole A, Rowland W 1655 The practice of physick … being chiefly a translation of the works of … Lazarus Riverius. Peter Cole, London. Davis PH (ed) 1978 Flora of Turkey, vol 6. Edinburgh University Press, Edinburgh. Dawson WR 1949 Chiron the Centaur. Journal of the History of Medicine 4:267–275. Do T, Popov S, Marekov N, et al 1987 Iridoids from Gentianaceae plants growing in Bulgaria. Planta Medica 53:580.
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THE WESTERN HERBAL TRADITION El-Sedawy AI, Shu YZ, Hattori M, et al 1989 Metabolism of swertiamarin from Swertia japonica by human intestinal bacteria. Planta Medica 55:147–150. Fernie WT 1897 Herbal simples approved for modern uses of cure. Boericke & Tafel, Philadelphia. Online. Available: http://www.gutenberg.org. Fuchs L (1545) 1980 edn. Holzschnitte, die historischen Taschenbücher. Konrad Kölbl, Grünwald bei München. Gibbons B, Brough P 1992 Wild flowers of Britain & Northern Europe. Chancellor Press, London. Griffin JP 2004 Venetian treacle and the foundation of medicines regulation. British Journal of Clinical Pharmacology 58:317–325. Gunther RT (ed.) 1933 The Greek herbal of Dioscorides. Oxford University Press, Oxford. Handjieva N, Saadi H, Popov S, et al 1991 Separation of iridoids by vacuum liquid chromatography. Phytochemical Analysis 2:130–133. Jensen SR, Schripsema J 2002 Chemotaxonomy and pharmacology of Gentianaceae. In: Struwe L, Albert VA (eds) 2002 Gentianaceae: systematics and natural history. Cambridge University Press, Cambridge. Larrey D, Vial T, Pauwels A, et al 1992 Hepatitis after germander Teucrium chamaedrys administration: another instance of herbal medicine hepatotoxicity. Annals of Internal Medicine 117:129–132. Kumarasamy Y, Nahar L, Cox P, et al 2003a Bioactivity of secoiridoid glycosides from Centaurium erythraea. Phytomedicine 10:344–347. Kumarasamy Y, Nahar L, Sarker SD 2003b Bioactivity of gentiopicroside from the aerial parts of Centaurium erythraea. Fitoterapia 74:151–154. Lange D 1998 Europe’s medicinal and aromatic plants: their use, trade and conservation. Traffic International, Cambridge. Mansion G, Struwe L 2004 Generic delimitation and phylogenetic relationships within the subtribe Chironiinae (Chironieae: Gentianaceae), with special reference to Centaurium: evidence from nrDNA and cpDNA sequences. Molecular Phylogenetics and Evolution 32:951–977. Meszáros S, De Laet J, Smets E 1996 Phylogeny of temperate Gentianaceae: a morphological approach. Systematic Botany 21:153–168. MHRA 2003 Aristolochia. Online. Available: http:// www.mhra.gov.uk/Howweregulate/Medicines/ Herbalandhomoeopathicmedicines/Herbalmedicines/ HerbalSafetyNews/Furthersafetyissues/CON024018. Mills S 2003 ESCOP Monographs: the scientific foundation for herbal medicinal products, 2nd edn. Thieme Medical Publishers, Stuttgart. Moussaieffa A, Frideb E, Amarc Z, et al 2005 The Jerusalem balsam: from the Franciscan monastery in the old city of Jerusalem to Martindale 33. Journal of Ethnopharmacology 101:16–26. Nikolova-Damyanova B, Handjieva N 1996 Quantitative determination of swertiamarin and gentiopicroside in
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Centaurium erythrea and C. turcicum by densitometry. Phytochemical Analysis 7:140–142. Norton S 2006 The pharmacology of Mithridatum: a 2000-year old remedy. Molecular Interventions 6:60–66. Nutton V 1983 The seeds of disease: an explanation of contagion and infection from the Greeks to the Renaissance. Medical History 27:1–34. Riddle JM 1991 Oral contraceptives and early-term abortifacients during classical antiquity and the Middle Ages. Past and Present 132:3–32. Riddle JM 1992 Contraception and abortion from the ancient world to the Renaissance. Harvard University Press, Cambridge, MA. Schimmer O, Mauthner H 1996 Polymethoxylated xanthones from the herb of Centaurium erythraea with strong antimutagenic properties in Salmonella typhimurium. Planta Medica 62:561–564. Schulz V, Hansel R, Tyler V 1998 Rational phytotherapy. Springer-Verlag, Berlin. Spivack BS 1991 A C Celsus: Roman Medicus. Journal of the History of Medicine and Allied Sciences 46:143–157. Stace C 1991 New flora of the British Isles. Cambridge University Press, Cambridge. Sterry P 2006 Complete British wild flowers. HarperCollins, London. Theoi Project 2008 Kheiron. Online. Available: http:// www.theoi.com/Georgikos/KentaurosKheiron.html. Thomson AT 1815 The London dispensatory. Longman, Hurst, Rees, Orme, and Brown, London. Tutin TG, Heywood VH, Burges NA, et al 1973 Flora Europaea, vol 3. Cambridge University Press, Cambridge. UK biodiversity action plan 2009 Joint Nature Conservation Committee. Online. Available: http://www.ukbap.org.uk. Valentão P, Fernandas E, Carvalho F, et al 2001 Antioxidant activity of Centaurium erythraea infusion evidenced by its superoxide radical scavenging and xanthine oxidase inhibitory activity. Journal of Agricultural and Food Chemistry 49:3476–3479. Valentão P, Andrade PB, Silva E, et al 2002 Methoxylated xanthones in the quality control of small centaury Centaurium erythraea flowering tops. Journal of Agricultural and Food Chemistry 50:460–463. Valentão P, Andrade PB, Silva AMS, et al 2003 Isolation and structural elucidation of 5-formyl-2,3dihydroisocoumarin from Centaurium erythraea aerial parts. Natural Product Research 17:361–364. Van der Sluis WG, Labadie RP 1981 Secoiridoids and xanthones in the genus Centaurium. Planta Medica 41:150–160. Williamson E 2003 Potter’s Herbal Cyclopaedia. CW Daniel, Saffron Walden. Woolley B 2004 Heal thyself. HarperCollins, New York. Zeylstra H 1985a Centaury. New Herbal Practitioner 12:2–6. Zeylstra H 1985b The pharmacology of bitters. New Herbal Practitioner 12:20–21.
Centaurium erythraea, centaury DESCRIPTION Family: Gentianaceae
Part used: aerial parts
Centaurium erythraea Rafn. is a variable biennial or annual found throughout Europe, mainly on calcareous soils and dry grassy places, including sand dunes and chalky uplands (Gibbons & Brough 1992). There are about 14 species of Centaurium in Europe but there is disagreement over their identification and infraspecific hybrids occur which are also interfertile so the identity of local populations can be unclear (Tutin et al 1973). The Flora of Turkey (Davis 1978) gives five Centaurium species, including Centaurium erythraea. Smooth, erect stems (10–50 cm) arise from a basal rosette of smooth, oval, greyish-green leaves and bear opposite, narrow, smooth stem leaves with three veins. Small, tubular, pink flowers with five petals occur in summer in a branched inflorescence at the top of the stem. Many small seeds form in cylindrical capsules and the anthers coil after dehiscence.
Quality Collect when in flower (Bisset & Wichtl 2001). Bradley (2006) states that the greatest bitterness is in two esters of sweroside found in the flower ovary. Wild collection should be avoided as calcareous grassland is a priority habitat listed on the UK Biodiversity Action Plan (2009). This annual plant is a priority for cultivation, especially as Cullen (1775) states that plants are larger and more bitter when grown on fertile soil. Studies on the taxonomy of the Gentianaceae disagree (Meszáros et al 1996, Mansion & Struwe 2004) and there is debate on the number of species because of variation within species depending on environment. There is some hybridization between Centaurium erythraea and other species such as lesser centaury Centaurium pulchellum, which is a smaller annual with no basal rosette and fewer flowers often found on moist grassland near the sea, seaside centaury Centaurium littorale, which has distinctive narrow oblong leaves (Stace 1991) and is found in sandy turf and dunes, and perennial centaury Centaurium scilloides, which is distinguished by its procumbent habit with rounded, stalked leaves on the creeping stems, and is a rare plant found on cliff tops (Sterry 2006). Other species used: Centaurium uliginosum, Centaurium littorale, Centaurium pulchellum (Van der Sluis & Labadie 1981). Culpeper also refers to a yellow variety with larger, darker green leaves and the stem passing through the middle of the leaf. This could be yellow wort Blackstonia perfoliata, an annual (Stace 1991) that is locally common on calcareous grassland. Culpeper also refers to a white flowered species, which could be Centaurium tenuiflorum, an annual and similar to Centaurium pulchellum, which is usually pink but rarely white. Centaurium tenuiflorum and Centaurium scilloides were both listed as vulnerable in the UK in 1994 (UK Biodiversity Action Plan 2009). Centaurium erythraea is listed as vulnerable and Centaurium uliginosum is listed as endangered in the Czech Republic, and Centaurium erythraea is listed as threatened by wild collection in Hungary (Lange 1998).
LESSER CENTAURY, GREATER CENTAURY AND CHIRON, THE CENTAUR Dioscorides (III 7) describes lesser centaury with an angular stem over a span long, resembling St John’s wort or oregano, with flowers faintly purple like rose campion, small and longish leaves like rue, fruit like grains of wheat and a small useless bitter root. The use of comparisons is © 2009 Elsevier Ltd, Inc, BV DOI: 10.1016/B978-0-443-10344-5.00018-5
interesting: St John’s wort Hypericum perforatum also has a smooth stem with small opposite leaves and a branched flowerhead. This description can be taken as common centaury. The only discrepancy is that, as Fuchs comments, according to Dioscorides, it grows in marshy places whereas ‘everyone knows that with us it grows commonly in hard, dry, grassy fields and meadows’. Dioscorides uses the name centaury for two plants: the lesser centaury and the greater centaury (III 6), which is a metre tall with blue flowers, serrated walnut-like leaves and a substantial red root. It is probably a knapweed in
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Figure 13.1 Centaurium erythraea, centaury (near Fondi, Italy, July).
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Centaurium erythraea, centaury the genus Centaurea. Lesser means the smaller of the two related plants, and this monograph discusses the use of the lesser centaury, which is now called common centaury and remains in use today. The illustration given by Fuchs is of centaury (1980) and later authors such as Culpeper and Miller continue to refer to ‘the red ordinary small centaury’. The two plants are very distinguishable but this introduces the possibility of confusion between the two entries in subsequent herbals. The listing of two unrelated species is significant as centaury is one of the four panaceas ascribed by Pliny to Chiron, the centaur who is the archetype of healers (Bostock 1855). The four panaceas were Asclepion, Heracleon, Chironion and Centaurion, and Dawson (1949) gives Centaurion as Centaurea centaurium L. The association with Chiron, the centaur indicates the long usage of these plants and associates both with wound healing. For example, in the Iliad of Homer, which describes the Trojan War, Eurypylos says, ‘Cut the arrow out of my thigh … and put kind medicines on it, good ones, which they say you have been told of by Akhilleus, since Kheiron, most righteous of the Kentauroi, told him about them’ (Theoi Project 2008). Old ulcers that refused to heal were called Chironian, as if requiring Chiron himself to heal them (Dawson 1949). The connection is worth investigating as centaury was used by Chiron to treat what was ultimately his fatal wound, as he eventually died because of a wound that could not be healed. Chiron, the centaur ‘half like a horse, half a god’, was the son of Saturn (Cronos) and the nymph Philyra who was a daughter of Ocean. Chiron lived with his wife Chariclon in a cave on Mount Pelion in Greece and was the tutor of Asclepius, god of medicine, and reared Achilles (Dawson 1949). When Hercules was passing by on his labours in search of the Erymantian boar, Chiron was accidentally wounded by one of Hercules’ poisoned arrows. One version states that he was wounded in the knee by an arrow meant for other centaurs and Hercules applied a healing herb, and another version states that Chiron dropped the arrow on his left foot by mistake. The arrow was poisoned with the blood or gall of the Hydra, and this fulfilled the prophecy of Chiron’s daughter that he would long for death, although immortal, and his death would be caused by a serpent. Chiron was immortal and could not die, but was released from immortality by Prometheus, who offered himself to Zeus to be immortal in Chiron’s stead. The significance of these events as recounted by Ovid is heightened by the presence of Achilles, who mourns for his mentor, which links this archaic event with the events of the Trojan War (Brookes 1994). Brookes also comments that Ovid uses the word ‘foot’ rather than ‘hoof’ and notes the linkage with the eventual death of Achilles from an arrow-shot in the foot. He further notes a linkage with the eventual death of Hercules, who died on a pyre to escape the pain caused by a shirt sent by his wife Deianira. The
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shirt was smeared with the blood of the centaur Nessus, which was infected by the Hydra. Returning to the recommendations of the mortals, greater centaury has a large, red astringent root and, comparing the two entries in Dioscorides, the emphasis is more on wound healing for greater centaury than it is for common centaury, and common centaury may not be the wound herb of Chiron. However, it is also strongly recommended for use in wounds. Mattioli argues that the Arabic writers confounded lesser and greater centaury and thus the texts are unclear, but later texts also lack clarity. Some authors consider them together whereas others give two entries.
WOUND HEALING The initial advice of Dioscorides on centaury is unclear as he refers to the ‘small useless root’ of common centaury but then recommends the pounded root as a plaster for injuries, and to cleanse old ulcers to form a scar. Mattioli cites Galen as stating that the root of lesser centaury is ineffective but the aerial parts are most useful. Galen states that the bitter quality permeates them yet there is a little astringency, which makes it an ideal drying medicine without being harsh or stinging: ‘Therefore, large wounds are closed up by anointing of this fresh herb; and old ulcers which can hardly be induced to scar over, are scarred over by using it in the same way. Dried, it is put among the herbs with gluing and drying properties, those evidently which are destined by nature to heal sinuses and fistulas and soften old hardnesses, and to heal malignant ulcers’. Fuchs also cites Galen giving the same details, and the advice is repeated by Dodoens and in less detail by Gerard. Serapio writes similarly and advises common centaury for fistulas and indolent or deep ulcers either as the fresh plant or as the dried plant with emollient herbs. Ibn Sina describes the two centauries but does not distinguish in his recommendations. He states that centaury cleans fresh wounds and closes old ulcers, and that dried centaury is used in preparations for plasters for use in fistulas, including ‘lacrimal fistulas’. This last recommendation for use in fistulas is also made by Dodoens, who advises the powder of dried aerial parts. We find that Culpeper recommends the fresh herb bruised and applied to close up fresh wounds and for old ulcers and sores ‘perfectly to cure them both although they are hollow and fistulous’. Later recommendations are less specific: Miller suggests external use in fomentations against swellings and inflammations. Quincy refers to the fomentation as discutient, dispersing morbid matter, whereas Coffin refers to use of a strong tea in scrophula (see the discussion under figwort, Chapter 28) and longstanding ulcers without specifying whether it be drunk or applied.
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Figure 13.2 Centaurium erythraea, centaury.
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Centaurium erythraea, centaury Further external usages are explained by Dioscorides, who describes the preparation of juices from the aerial parts collected when in seed. The fresh herb is soaked for 5 days, boiled hard, strained and then boiled again until it reaches a honey-like consistency. Given the scarcity of centaury, and the difficulties of producing a sterile pre paration, then this preparation would present some challenges. Dioscorides recommends the juice for eye conditions, cleansing with honey ‘those elements that cast a shadow over the eyes’. This is repeated by Fuchs, citing Galen, and by Dodoens, Parkinson and Gerard. Another external recommendation that is hard to interpret is made by the Salernitan herbal, which recommends local application of the juice with leek juice for ‘worms in the ears’. This could be otitis external or Beck suggests ear wax. This is also repeated by Parkinson, who recommends the decoction dropped into the ears to remove ‘worms’. Culpeper repeats Parkinson and both recommend external usage for scabs, freckles and spreading scabs of the head. This is copied by Grieve and thus has been copied onto websites which give herbal information. The transmission of the texts is unclear and recommendations are not possible for this paragraph.
‘HIP AILMENTS’ AND MUSCULOSKELETAL CONDITIONS The herb is consistently recommended both for external usage and internal usage and it is not always apparent which is being recommended. First I will discuss external and internal usage for muscular pain and arthritis, and then move on to internal use as a bitter, which is the most common usage today. Dioscorides states that the decoction of the root is a suitable enema for hip ailments delivering blood and relief. Gunther (1933) gives this as ‘a fit glister (enema) for the Ischiaticall, draweth out blood and easing the pain’. Serapio writes that the decoction is useful as an enema to treat sciatica as it expels choleric humours. Turner uses the text of Dioscorides and states that ‘the broth is good for sciatica as it draweth the blood and easeth the pain’. Descriptions of hip pain sound more like osteoarthritis of the hip or septic arthritis than the use of the term sciatica today to describe pain extending from the hip down the leg. Fuchs, citing Galen, states that some pour the decoction on hip pains. Ibn Sina may shed more light on use in hip ailments as he advises centaury for muscle tears and the appearance of pus there. He advises use of an enema in sciatica, nerve pain and tears and that if blood comes out then this is beneficial. This version is more clear than in some authors and suggests that he means discharge of blood from the wound and thus cleansing of the wound. Gerard comments that although the ancient authors
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consider that centaury purges by stool, he has never found it so but has found it useful in sciatica. Some authors such as Dodoens suggest that blood in the stool is a useful result of treatment, which cannot be the case. Dioscorides also advises the juice for ‘ailments around the tendons’, which is given as diseases of the sinews by Turner and Dodoens. Mattioli, citing Galen, states that it is counted among those which heal rheumatic afflictions, for which those medicines are best which are strongly drying and somewhat astringent but not too sharp. Fuchs gives this slightly differently, specifying that centaury is useful in rheumatic afflictions where vehement drying and astringent qualities are needed without any sharpness. These recommendations are followed by Parkinson and Culpeper with the addition of ague and old joint pains; ‘with other things to dry up rheum’. The area around the joints was visualized as being stretched because of the flow of the phlegmatic humour into the area, and thus herbs were needed to dry up or promote the flow of this humour (Culpeper et al 1655). This links with the descriptions of temperament: centaury is described as hot and dry in the third degree by Ibn Sina, and hot and dry in the second degree by Dodoens and Culpeper. Bauhin states that the pills are useful for those with sciatica, defects of the nerves and gout. Riviere (Culpeper et al 1655) discusses gout and its causes. The word ‘gout’ was used for gout as we understand it today, and also for pain in other joints, including sciatica or hip gout. Centaury continued to be used for gout and Grieve notes its use in the once famous Portland powder, which was a recipe purchased and published by the Duke of Portland (Thomson 1815).The powder contained equal portions of aerial parts of centaury, germander Teucrium chamaedrys, ground pine Ajuga chaemapitys and the root of gentian Gentiana lutea and birthwort Aristolochia species. Two of these ingredients are no longer used: Aristolochia species have been banned because of an association with kidney failure (MHRA 2003) and Teucrium chamaedrys has been associated with cases of serious hepatotoxicity linked with the use of slimming teas (Larrey et al 1992). The dose of Portland powder was 1 drachm (4 g) to be taken every morning, fasting for 3 months; then 3 4 dram (3 g) for a further 3 months and so on for a year; then 1 2 dram (2 g) on alternate mornings for a further year. Buchanan and Kean (1987), however, cite Heberden as saying that this remedy rose too fast and fell too far. There is a linkage between external usage in old wounds, in sciatica and disease associated with the tendons and with internal use for gout. Other bitter tonics such as bogbean Menyanthes trifoliata continue to be used internally in musculoskeletal pain. Fernie (1897) refers to use of the hot infusion of centaury for muscular rheumatism. Quincy suggests that some say it is febrifuge, especially in tertian fevers and Hill states that ‘country people cure agues with it’. Again this usage appears to be based on the recommendation of Galen, who described it as evacuating
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THE WESTERN HERBAL TRADITION the choleric humour from the body. Galen is cited by Dalechamps as linking use of the decoction for tertian fever with the action of expelling bile via the rectum. The French version of Mattioli adds to the discussion of centaury by proposing that the decoction helps greatly the tertian agues, for it makes bile leave downwards, and thus it is called febrifuge, ‘chasse-fièvre’.
BEST BITTER AND VISCOUS HUMOURS Having looked at external application and usage for painful joints, we come to the main current usage of centaury, which is as a bitter. Employment as a bitter tonic with an influence on bile flow appears to have been continuous since the time of Dioscorides. This usage is continued into more modern texts and one gains the impression that authors are writing from experience. For example, Coffin states ‘for many years we have used it with great success where the digestive organs have been seriously impaired’. This is repeated in current texts such as Hoffmann who refers to it as indicated primarily in anorexia especially if associated with liver weakness, indigestion and any condition where a sluggish digestion is involved. My personal experience is that it is an excellently well-tolerated herb and useful in poor appetite in the elderly and in small children. Interestingly, however, we still have Dioscorides to thank for the original recommendation ‘the root boiled and drunk, dispels through the bowels matter that is bilious and thick’. Mesue, cited by Serapio, advises 2 drachms (8 g) in decoction to purge thick phlegm. Ibn Sina recommends centaury for obstructions of the liver and as a remedy for a hardened spleen both as a drink and applied topically, which recommendations are repeated by various authors including Culpeper. Ibn Sina advises 6 g as a decoction for colic and states that sometimes the decoction cleanses mucous and unripe humours as well as yellow bile. Mattioli states that Galen wrote an entire treatise on centaury dedicated to the town of Papia and argues that it removes bile and phlegm, which the greater centaury does not. Fuchs also cites Galen at length and advises centaury to purge bilious and thick humours and resolve obstructions of the liver. Fuchs also cites Pliny as recommending 1 drachm (4 g) in 1 hemina (about 270 mL) of water with a little salt and vinegar to purge the bowels and draw down the bile. Turner states that it drives out choler and gross humours via the belly, and Dodoens advises it boiled in water or wine for this purpose but links this usage with sciatica. Parkinson states that it thins the blood and humours and purges choleric and green humours. Culpeper states that it purges choleric and gross humours,
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and is especially good for the blood. He recommends a decoction of aerial parts for colic and jaundice; it ‘opens obstructions of liver, gall and spleen’ as well as being useful for gout and cramps in joints. Quincy claims that it ‘discusses and absturges viscous humours’ and increases discharge by stool or urine but also helps to thin these humours for evacuation through the skin. Quincy recommends a decoction or infusion in wine. Macer argues that centaury ‘dries up the wild humours of a man’s spleen’ which has been ‘often proved’. Fuchs cites Galen as stating that it is good for those whose nerves are affected. Mattioli says that there are those who recommend it for those affected by nerves, in that it empties out and dries harmlessly those things which are full. Dalechamps gives this as ‘those with nervous afflictions or who are full of humours’. Bauhin suggests that advice for use of centaury in nerve disease such as apoplexy, paralysis and epilepsy is based on the action of centaury to ‘pull things away from the intestine’. Reading these recommendations, one thinks of the importance that Fuchs gives to pictures as representing the form and thus the nature of the plant. Words can sometimes express so little about the actions and quality of a herb. The advice of Macer makes one think of the pure, clean bitter taste of centaury, as if it would regulate flow and thus purify the spirit. Modern authors such as Menzies-Trull and Wood recommend centaury in depression associated with digestive disturbance and Wood gives the recommendation of Fernie (1897) for use in ‘languid digestion’ with heartburn after food. He also discusses the connection between this action and the use of the Bach flower essence of centaury for courage and to help the person to speak out. Pelikan describes centaury as ‘open and friendly yet reticent’. He refers to the medicinal function of bitters as to ‘make the ether body inclined to receive the astral body’, hence the etheric aspect of the organs serving metabolism will be suffused with astral influence, allowing a vigorous and healthy response to the ingested food. ‘The right appetites will then arise, the fluid organism will be toned and conscious awareness strengthened’. Returning to the physical, usage as an anthelmintic is not mentioned by Dioscorides but it is recommended by Ibn Sina and then the Salernitan herbal for ‘worms in the belly.’ Apuleius advises the herb crushed in vinegar for worms and this appears in Turner, Dalechamps, Parkinson and Culpeper. Parkinson, copied by Culpeper, states that he has found it useful. A continuing theme is that centaury is both bitter, thus creating an appetite, and a pleasant stomachic in indigestion. Culpeper claims that ‘the herb is so safe you cannot fail in the using of it’. Other writers note its agreeable and pleasant nature including Miller, Quincy, Cullen, Coffin, Robinson, Fox, Fernie, Hool and Grieve. Some authors, such as Gerard and Hill emphasize a powerful action on the liver and use of the powder in jaundice.
Centaurium erythraea, centaury Pelikan links this dual action to centaury as it develops more in the direction of stem and stalk than the more usually flower-centred gentians and will therefore work on the ‘rhythmic element in metabolism’. It is thus useful, he says, for ‘lack of appetite, poor gastric function, gastritis, heartburn, to stimulate hepatic and biliary activity and in cases of jaundice’. According to Zeylstra (1985a), centaury is used for heartburn and hyperacidity and he cites Kniepp as advising it for heartburn and to relieve the stomach of superfluous winds. Zeylstra (1985b) advocates taking bitters at least 30 minutes before meals and sipped in water for maximum effect. The Myddfai also emphasize use as a bitter stomachic, advising centaury for poor appetite, pain in the cardiac area (possibly heartburn) and pain extending to the shoulder, which could be referred pain from the gall bladder. My experience of using it as a tincture is that it is a bitter tonic that is effective without being too strong. Coffin recommends it alone, with other bitters or with raspberry Rubus idaeus in weak and debilitated patients where the digestive organs are seriously impaired. Hool recommends a tonic for the delicate or elderly: centaury 1 2 oz, raspberry Rubus idaeus 1 2 oz, infuse in 1 pint. Take a wineglassful (60 mL) four times a day. The British Herbal Pharmacopoiea recommends it as a carminative in dyspepsia, in anorexia and in children with gastric or hepatic weakness. Schulz et al (1998) and Hoffmann list it in their discussion of bitters and note its use in anorexia. Menzies-Trull suggests that it is also useful when there is oversecretion of bile. There are other bitters, and for ecological reasons this herb is not the first choice. However, it is of particular service in people with low energy, including elderly people with poor appetite and my experience is that is very effective and well tolerated. It is also the herb of choice for children, who sometimes combine poor appetite with susceptibility to infections. The authors refer to its use in painful joints and when the nerves have been upset, and this leads to a recommendation for use where the person is debilitated due to illness. An example of this is traditional usage in Scotland of an infusion as a tonic, particularly to improve the appetite in tuberculosis sufferers (Beith 1995). I might include centaury where there are aches and pains associated with chronic fatigue syndrome or fibromyalgia.
EMMENAGOGUE? The expulsive action of centaury on humours leads us to another action of the herb. Hoffmann includes centaury in his list of bitters that are also emmenagogue but the evidence for this statement needs some discussion. Both greater centaury and centaury are referred to as ‘drawing down the menses’ when used as a pessary. Riddle (1991) cites Oribasius, writing in the 4th century AD, as listing the
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following herbs for an antifertility action: beaten wormwood, pennyroyal, century plant, thyme, rue and others. As discussed in other monographs, the meaning of the word emmenagogue varies and can refer to abortifacients, herbs useful if the menstrual cycle is irregular and herbs traditionally used in the management of labour. Riddle (1992) discusses the many problems in interpreting texts. He argues that the word emmenagogue was used as a code and that herbs were used as contraceptives throughout history, in particular to avoid conception. The evidence on centaury is particularly difficult to interpret as two dissimilar herbs are discussed by the authors. With regard to greater centaury, Discorides states that ‘the root draws down the menses and the embryos/ foetuses when whittled, shaped like a pessary and applied to the uterus. The juice accomplishes the same’. With regard to lesser centaury, Dioscorides states that the juice, probably of aerial parts, ‘induces menstruation and abortion when used as a pessary’. Ibn Sina affirms that centaury stimulates urine and the menses, and expels the foetus. The Salernitan herbal states that it provokes menstruation as a poultice, or pessary. Turner advises that the juice ‘laid in with wool in the natural place, bringeth down womens sickness’, and Dodoens suggests use of a pessary for the same purpose and to expel the dead child. Parkinson refers to centaury as emmenagogue, to expel the foetus and ease period pains. Culpeper advises it for the pain associated with a still birth. To conclude, it could be argued that this suggests caution in use of a tea in pregnancy (see Recommendations on safety).
ALEXIPHARMIC PANACEA Finally, centaury is recommended as an alexipharmic, for example by Quincy. Alexipharmics are substances considered to protect the heart against poison, in particular after venomous bites. Apulieus proposes the herb crushed in vinegar to dispel the poison after a bite of a viper. Parkinson and Culpeper recommend 1 drachm (4 g) of powder for snakebite in wine, and Culpeper adds that is ‘wonderful good against the biting and poisons of an adder’. This links with a use as an antidote to poisons. Pliny refers to the Gauls using it against poisoning. The healing of inflammation from wounds and protection against wounds or snake bites is an ancient theme in the use of centaury as it was an ingredient in Mithridatum. This remedy is based on a formula sent by Zopyrus, physician to King Ptolemy of Egypt, to Mithridates VI (d. 63 BC), King of Pontus, which is an area west from Trabzon on the southern shore of the Black Sea. The formula contains 20 aromatic plants, including ginger, myrrh and centaury, of which 15 remained in the formula of 36 ingredients proposed by Celsus (Norton 2006). This is advocated for protection against poisons in food or venomous bites, and
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THE WESTERN HERBAL TRADITION ‘serious conditions’ by Celsus (25 BC-50 AD), a Roman doctor who wrote a substantial work on medicine, which was published in 1478 and was thus one of the first printed books (Spivack 1991). This formula was used as the basis of Theriac by Galen and remained in pharmacopoeias to the 17th century. Discrepancies and substitutions in the Theraic of Mithridates were one of the spurs to the production of the Pharmacopoeia Londinensis, published in Latin in 1618 (Griffin 2004). Other compound medicines such as Theriac Londinensis, London treacle, were also used to resist pestilence (Woolley 2004). Pestilence, in the days of infectious disease, plague, contaminated water and badly stored food was a much broader concept than snake bites, so alexipharmic remedies can be seen as preventing disease in a wider sense. Although transmission by bacteria had not been identified, the contagious nature of many diseases was well-known (Nutton 1983). Jerusalem balsam was another panacea used in Europe that was formulated at the Franciscan monastery of St Saviour in Jerusalem at the beginning of the 17th century (Moussaieffa et al 2005). Centaury was included in one formula of 40 ingredients found in Venice which dates from the early 18th century. Given the earlier discussion of internal and external use of centaury, it is interesting that the same remedy was used both externally on wounds, including gunshot wounds and fistulas, and also daily in small doses in food to resist infectious diseases. This recalls Ibn Sina and Apuleius, who both advise that internal usage will heal wounds. Apuleius advises a decoction in water boiled down to a third part. Centaury continues to be used today in Turkey for chronic inflamed wounds, either as a tea of aerial parts or as a salve made with olive oil (Berkan et al 1991). Brooke (1992), maybe in a reference back to the story of Chiron, Hercules and Achilles, argues that centaury is useful to face the day with courage, to stand up for yourself, and to drink ‘before a long journey where trials of strength are to be attempted’. The alexipharmic action in treating wounds and acute infection could be used again in current herbal medicine in treatment in acute situations, and the concept of an antidote taken regularly in small doses of herbal medicines to protect against infection remains a potent symbol of the power of herbs to preserve health.
RECOMMENDATIONS • External usage for chronic wounds is recommended by all the authors and the detailed advice of Galen suggests experience with this herb. Although this usage has not been continued to the present day, the authors do give it prominence and it could be reintroduced as long as the source of the plant material is sustainable. • Internal usage for arthritis, muscular and joint pain can be recommended, particularly associated with depression, fibromyalgia or where the person is recovering from illness. • The British Herbal Pharmacopoiea recommends it as a bitter, aromatic and stomachic for use in anorexia, dyspepsia and in children with gastric or hepatic weakness. One has to broaden this recommendation to usage wherever there is poor appetite, also in conditions such as irritable bowel syndrome where a mild but effective medicine is required. Given the emphasis by the authors on the action of centaury to drive out choleric humours, phlegm and unripe humours, then it may have a more dynamic action on the bowels as a tea than in the more common modern form of a tincture. • The authors recommend a decoction of aerial parts in flower. A decoction for use in acute situations such as wounds, bites or stings could include centaury alongside other herbs such as yarrow Achillea millefolium and comfrey leaf Symphytum officinale. • A small dose in a medicine to prevent reoccurrence of a chronic condition such as irritable bowel could be seen as harking back to the recommendation as an alexipharmic. Dosage: the British Herbal Pharmacopoeia recommends 2–4 g three times a day of dried flowering aerial parts. Ibn Sina gives the dose of 6 g for colic and uterine pains, which corresponds, somewhat astonishingly, with the daily dose given by Commission E (Blumenthal 1998). The doses used by herbalists as medicines are often very small, for example 10–15 mL weekly of a 1 : 5 tincture, which is equivalent to 400 mg daily.
CONSTITUENTS Reviews: Barnes et al (2007), Bisset & Wichtl (2001), Bradley (2006), Mills (2003), Williamson (2003).
Secoiridoid glycosides Secoiridoid glycosides are bitter compounds that are characteristic of Gentianaceae, and representatives of three types are found: swertiamarin; sweroside and two related compounds, gentiopicroside and gentioflavoside. Secoiridoid glycosides
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Centaurium erythraea, centaury
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are the main compounds found in centaury but derivatives of the iridoid glycoside loganic acid and intermediate compounds (secologanol and centauroside) are also found (Jensen & Schripsema 2002). Particularly bitter esters of secoirioid glycosides accumulate in the seeds (Van der Sluis & Labadie 1981). Total 1.2%: swertiamarin, sweroside (Kumarasamy et al 2003a), gentiopicroside (Kumarasamy et al 2003b). Swertiamarin 0.5–8.8%, gentiopicroside, no sweroside (wild, five populations, Bulgaria) (Nikolova-Damyanova & Handjieva 1996). Swertiamarin (predominant), gentioflavoside, dihydrocornin (Do et al 1987). Monoterpene iridoid alkaloids gentianine, gentianidine, gentioflavine were derived from iridoid glycosides (Handjieva et al 1991) and anaerobic incubation of swertiamarine with intestinal bacteria showed that three main metabolites were produced, including erythrocentaurin and gentianine (El-Sedawy et al 1989).
Sterols Beta-sitosterol, stigmasterol, campesterol, brassicasterol, delta 7 stigmastenol (aerial parts) (Aquino et al 1985).
Phenolic acids Hydroxycinnamic acids: p-coumaric acid, ferulic acid, sinapic acid (Valentão et al 2001).
Coumarins Isocoumarin (wild, Portugal) (Valentão et al 2003).
Flavonoids Flavone: kaempferol (Valentão et al 2001).
Xanthones Methoxylated xanthones: eustomin, demethyleustomin (wild, Morocco) (Schimmer & Mauthner 1996). Methoxylated xanthones: six, including eustomin; tetraoxygenated xanthones (12 samples) (Valentão et al 2002).
RECOMMENDATIONS ON SAFETY 1. Do not use centaury as a tea during pregnancy. 2. The uses of either centaury as a pessary is obviously
not advisable. In contrast, the doses used by herbalists as medicines are often very small and the conclusion has to be that centaury Centaurium erythraea is safe in pregnancy used thus.
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