Citrus species and their essential oils in traditional medicine

2015

The genus Citrus L. (Fam. Rutaceae) contains a large number of species (more than 400) (INDEX Kewensis, 1997) along with innumerable varieties, cultivars, etc. All cultivated species probably derive from plants native to tropical and subtropical zones of Southeast Asia ().

India would appear to be the original cradle of the Citrus genus. We find references to their usage in ancient Hindu medicine as Amara-Koscba () under the names Jambira (Citrus acida) and Nardnga (Citrus aurantium). The lemon is one of the remedies found in numerous treatises on Vedic-Brahminic medicine, the most important of which is the Susruta (1300 BC) ().

According to Bretschneider (1871), the Pent’ ts’ao Rang Mu, a book of Materia medica that draws together knowledge dating back thousands of years BC and is considered a true Pharmacopoeia, includes the fruits of Citrus digitata and Citrus japonica in section IV/2 (Mountain fruits).

Of the hundreds of species belonging to the Citrus genus, only a small number were extensively cultivated and acclimatised, initially in neighbouring countries and later, at the time of the conquests of Alexander the Great (330 BC), also in Greece and Palestine.

There is reliable documentation of the use of a very small number of Citrus species in the traditional medicine of the countries of origin and of the countries where the various species have naturalised.

Opinion is fairly divided () about the date when the most important species, including those used for medicinal purposes, were introduced to Europe and were first acclimatised and cultivated. The fact that synonymity between species and their numerous varieties is not always clear has also caused confusion.

The oldest existing record of the Citrus genus is the discovery in excavations of the city of Nippur, south of Babylon, of seeds identified as those of the citron, Citrus medica Risso. A biblical quotation (Leviticus, XXIII, 40) is believed to refer to this species, or one of its varieties Citrus medica var. lageriformis Roem. A citron fruit is also depicted on a coin minted by Simon Maccabeus in the fourth year of the Redemption of Zion (136 BC) ().

Various authors have identified the fruits of the ‘tree of knowledge of good and evil’ (Genesis II, 9,17; III, 6) in the Scriptures as the fruits of Citrus, and some Renaissance artists conformed to this interpretation in their representations of the Garden of Eden (). Van Eyck’s famous polypty Adoration of the Mystic Lamb, kept in the church of St. Bavon in Gand, portrays Eve holding an indeterminate fruit that bears a strong resemblance to a lemon ().

Apicius Caelius (third century AD) recommended preserving the titria in plaster and Alexander Trallianus (sixth century) prescribed the fruit flesh and juice of the lemon ().

Theophrastus Heresius, a philosopher of the school of Aristotle, who was born at Eresos in Lesbos in 371 BC, drawing from the protocols of Alexander the Great’s Asian expeditions, in Book IV (Chap. IV, 2) of Historia plantarum provides the oldest botanical description of the citron, calling it …, from its regions of origin, Media and Persia. He adds that placing the inedible fruit and the leaves among clothes protects them against worms (clothes moths?) and when administered in wine in cases of poisoning they trigger evacuation of the alvus and hence eliminate the poison; they also freshen bad breath; these reports were picked up again by later writers (e.g. Pliny, 1831).

The citron was also the first species of the Citrus genus known in Europe. The first attempts to acclimatise it in Italy date from the time of Pliny. Wehrmahn (1912) found a representation of it in a fresco in Herculaneum.

Most authors believe that the lemon was unknown to the ancient Greeks and Romans and was introduced to the Mediterranean area and the rest of Europe from India, via Persia and Palestine, much later than the citron. Fluckiger and Hanbury (1878) maintain that the tree was introduced to Europe by the Arabs, but are uncertain about the exact date. This opinion is generally shared among even the most recent specialist publications and treatises on Pharmacognosy (), which set the date of its introduction as between the tenth and twelfth centuries. Tschirch (1917), who cites information from the ancient authors, suggests that these may sometimes refer to the citron. He observes that the lemon does not appear in the wall paintings of Pompeii and is not mentioned by most of the agricultural publications of the Roman writers, and concludes generically that it reached Europe and Italy much later than the citron.

However, the recent discovery of the paintings in the orchard house (casa del frutteto) in Pompeii in which lemon trees are accurately depicted, clearly proves that this species, along with others of the Citrus genus such as the citron and perhaps also the orange and lime (), was well-known and widely cultivated in Italy many centuries prior to the Arab expansion.

In Naturalis Historia (Plinii, 1831), book XIII/16, Pliny (Caius Plinius Secundus, 23-79 AD), known as Pliny the Elder, talks of a tree that bears fragrant fruit with a bitter taste and is grown as an ornamental. In book XXIII/56 he specifies that the fruits (citrea) and seeds, when placed in wine, are used to counteract venom, and that their decoction is used to perfume the mouth; the seeds, if eaten, are harmful to pregnant women but are used for treating stomach ailments.

In the same century the Greek Pedacius Dioscorides from Anazarbus in Cilicia (born 50 AD), a Roman army physician under Nero, travelled with the troops through Egypt, Africa, Spain and Italy and brought together all known information on medicaments in use in a book entitled ‘della materid (on the raw materials provided by nature), a title to which copyists later added the adjective medicinal, since the therapeutic uses of each drug were given along with their description. In this book we find the ‘Persica mela’ (Citrus medico), the fruit of which was held to be useful for the stomach and the belly.

Dioscorides’ book was translated into Latin under the title ‘De Materia Medica and was highly influential not only in the Roman and Arab worlds but also well into the Middle Ages. Dioscorides’ fame was such that he was referred to by Dante Alighieri in the Divine Comedy

e vidi il buon accoglitor del quale Dioscoride dico

(Inf. IV, 139-140)

I saw the good collector of medirinals, I mean Dioscorides

(Inf. IV, 139-140)

The many reprints of Dioscorides’ book, in Latin and Vulgar, frequently expanded with annotations by the various authors, became the Bible of doctors and apothecaries.

One of the most famous re-editions (1557) is that of Pietro Andrea Mattioli (1504— 1577) of Siena, who commented and illustrated Dioscorides’ descriptions with figures of the plants. Up until the eighteenth century this re-edition was the textbook for medical schools, used to train generations of physicians. In the extensive commentary to the chapter mele di Media, ovvero Cedromele, che da latini si chiamano Citria, Mattioli distinguishes citrons from oranges and lemons and recounts legends telling of the potency of citron fruits against asp venom. He also describes the efficacy of the juice against plague and cholera and enumerates a series of generic actions performed by the fruit’s peel and flesh, described principally as amara (bitter). He maintains that the effects of the citron are not substantially different from those of the lemon, the ‘pomi d’Adamo o Lomia or the orange, adding that in Italy there exist three species of oranges, ‘acetosi, mezani, e dolci’ (bitter, slightly bitter, and sweet).

The Tbeatrum Sanitatis (1940), codex No. 4184 of the Casenatense Library in Rome, from the late fourteenth century, contains descriptions of the activity and toxicity of Cetrona et Citra together with miniatures of the plants.

Castore Durante (1529—1590), a doctor and citizen of Rome, illustrated a Herbaria (Durante, 1585) with splendid engravings of plants from European countries and from the East and West Indies and described their medicinal virtues with verses in Latin. He also provided an extensive commentary on the methods of preparation of suitable pharmaceutical forms and on the ways they were to be used in the most serious infirmities. Of the Citrus genus he described the properties of the citrons (in Latin Citria mala), the lemons (in Latin Mala limonia) and the oranges (in Latin Aurancia), interspersing their real (today confirmed) properties with a series of presumed therapeutic effects based on groundless popular belief. For example, orange flower water was held to be invaluable in combating pestilential fevers in the presence of petechiae, for strengthening the heart, easing childbirth, quickening the spirits, and so on, while the seeds were believed to be effective against scorpion stings (!!). The first edition of the Herbaria was published in 1585 and was followed by many others, all of which enjoyed enormous popularity.

In the Italian translation of the fourth edition (1766) of the ‘Dizionario ovvero Trattato Universale delle Droghe Semplici’ (Dictionary or Universal Treatise of Simples) by Nicolas Lemery, the heading Citreum includes Cedrum or Citro or Malum Citreum, of which the leaves and the flowers were used on rare occasions as cordials and fortifiers, more frequently the fruit peel to fortify the heart, the stomach and the brain and to withstand poison; the juice is cordial, refreshing, good for calming heat of the blood, for precipitating bile, for quenching thirst, and for counteracting venom; the seed is always cordial, and effective for resisting corruptions. The fruit, picked with cloves, should be kept in the pocket during epidemics and sniffed every so often to provide protection from contagion.

The same heading includes another species of citron, called the sweet citron, which is not used in medicine, and Citron essential oil, obtained from a species of Italian citron or bergamot (bergamot pear) which is cordial, stomachic, cephalic, and effective for ivarding off malign hmnours.

The lemons (limones, sive limonia mala) are included under a separate heading, and the virtues of the peel, the juice and the seeds were reputed to be similar to those of the citrons. The seeds were also believed to be useful in helminthiasis.

The Citrus in the Old Pharmacopoeias

The Citrus in the Chemist’s Shop in the Seventeenth and Eighteenth Centuries

Robert Talbor, nicknamed Talbot, first assistant in an apothecary shop, then apothecary (apothicaire) in Cambridge and ‘Pyretiatre (one who cures fevers) in London and later in France at the court of Louis XIV, realised that the posology and method of use of extract of cinchona bark in treating malaria had to be adapted to each patient. In 1682 he published ‘he Remede Anglais pour la Guerison des Fievres’, which contains a detailed description of his remedy for fevers based on extract of cinchona bark, including the note that in order to keep the drugs used in the preparation secret he added lemon together with the other aromas ().

In the seventeenth century the deeds of sale of apothecary shops included lists of the entire contents of the shop. In one such list drawn up for the sale of an apothecary shop in Carpentras (Provence) early in the seventeenth century we find distilled orange water (). In Savoy, to ward off the plague, lemon was boiled together with other medicinal herbs in white wine and the potion was drunk before journeying to unwholesome places. Large quantities of lemons were taken on long sea journeys to allay scurvy.

Napoleon Bonaparte had a liking for an eau de cologne with a formula containing essences of various Citrus species (bergamot, lemon, orange, neroli) as well as essence of rosemary.

The recipe for lemon balm water, also known as Carmelite water, developed by the Barefooted Carmelites of Paris in 1611, contains fresh lemon peel. The recipe for this preparation is reported as Aqua Melissae composita sen Vulgo Aqua Carmelitana sen Spiritus Melissa compositus in the Pharmacopea Manualis reformata, written by Benedicto Mojon in 1784.

According to Lagriffe (1979) the formula for aperitifs and bitters not only includes cardamom, juniper and rhubarb but also the peel of bigarade (bitter orange) in a sequence that a devotee described as follows:
The Citrus in the Chemist’s Shop in the Seventeenth and Eighteenth Centuries
Robert Talbor, nicknamed Talbot, first assistant in an apothecary shop, then apothecary (apothicaire) in Cambridge and ‘Pyretiatre (one who cures fevers) in London and later in France at the court of Louis XIV, realised that the posology and method of use of extract of cinchona bark in treating malaria had to be adapted to each patient. In 1682 he published ‘he Remede Anglais pour la Guerison des Fievres’, which contains a detailed description of his remedy for fevers based on extract of cinchona bark, including the note that in order to keep the drugs used in the preparation secret he added lemon together with the other aromas ().
In the seventeenth century the deeds of sale of apothecary shops included lists of the entire contents of the shop. In one such list drawn up for the sale of an apothecary shop in Carpentras (Provence) early in the seventeenth century we find distilled orange water (). In Savoy, to ward off the plague, lemon was boiled together with other medicinal herbs in white wine and the potion was drunk before journeying to unwholesome places. Large quantities of lemons were taken on long sea journeys to allay scurvy.
Napoleon Bonaparte had a liking for an eau de cologne with a formula containing essences of various Citrus species (bergamot, lemon, orange, neroli) as well as essence of rosemary.
The recipe for lemon balm water, also known as Carmelite water, developed by the Barefooted Carmelites of Paris in 1611, contains fresh lemon peel. The recipe for this preparation is reported as Aqua Melissae composita sen Vulgo Aqua Carmelitana sen Spiritus Melissa compositus in the Pharmacopea Manualis reformata, written by Benedicto Mojon in 1784.
According to Lagriffe (1979) the formula for aperitifs and bitters not only includes cardamom, juniper and rhubarb but also the peel of bigarade (bitter orange) in a sequence that a devotee described as follows:

Pour bien tonifier, du genievre en grains
De la rhubarbe pour liberer ventre et reins
Pour faire digerer, un peu de gentiane
Joindre pour empecher l’estomac d’eructer
Quelches graines d’amome
Aj outer quelches zestes de bigarade
Pour eclairer de celestes reves phosphorescents
La crane et l’exciter.
Use grams of juniper as an effective tonic,
Rhubarb to free the belly and the kidneys,
A little gentian to aid digestion,
Add a few cardamom seeds
to prevent the stomach from eructing,
Add bigarade peel
to lighten and stimulate the head
with blue phosphorescent dreams.

The Citrus in Pharmacology Treatises and in Therapy from the Eighteenth to Twentieth Centuries

Citrus in Traditional Medicine

 

Selections from the book: “Citrus. The Genus Citrus”. Edited by Giovanni Dugo and Angelo Di Giacomo. Series: “Medicinal and Aromatic Plants — Industrial Profiles”. 2002.