Citrus in Traditional Medicine

Citrus in traditional Asiatic medicine

In a comparative study of the use of herbal drugs in the traditional medicines of India and Europe, Pun () found a marked similarity between the drugs used in the two continents. He attributed this not only to the similarity of the vegetation in the two areas, but also to the influence that traditional Indian medicine, in particular the Atherveda, one of the most ancient repositories of human knowledge, had on Egypt, Greece and Rome. He listed the principal uses of a small number of these drugs, including bitter orange peel, which in India is used as an aromatic, stomachic, tonic, astringent and carminative agent, and lemon, which is used as a flavouring and for its carminative and stomachic effects.

In the Valmiki-Ramayana, written after the Vedas and one of the most sacred of all religious books which enumerates the virtues of the medicinal plants that Lord Rama (Vishnu) met during his fourteen-year journey around different parts of India, Karnick and Hocking () identified and listed fifty of these drugs with their use as described in the Ayurvedica (or native Indian) system of medicine. The immature fruit of Citrus aurantifolia (Christm) Swingle was used as an fortifier, cardiotonic, laxative, antihelminthic and for combating fatigue; the mature fruit as a sweetener, laxative and aphrodisiac; a decoction of the flowers for allaying fevers; the juice of the fruit as a tonic and for treating cases of swelling of the spleen; and the fruit peel as an anthelminthic.

In the Ayurveda the fruit of Limonia acidissima L. was used as a sour, sweet, acrid, refrigerant, aphrodisiac, alexipharmic; it cured dysentery, removed biliousness, vata, tridosha, asthma, tumours, and leucorrhoea. Juice was placed in the ear to cure earache. The unripe fruit was alexipharmic; the seed cured heart diseases; the essential oil was acrid, astringent, alexiteric and destroyed biliousness; the flowers were an antidote to poisons; the leaves were useful during vomiting, hiccoughing and dysentery.

A description of the use of Citrus species in traditional European medicine clearly shows how the ancient medical knowledge of India travelled to Europe and became an integral part of the medical culture.

In a medical investigation carried out from 1989 to 1992 in the Varanasi District of Uttar Pradesh, Bajpai et al. () report information on traditional species of Ayurvedic medicine used by the population living in rural areas to alleviate ailments. Lemon juice (Citrus aurantium L.) mixed with ground root bark of Strychnos mix-vomica L. is taken for loose motions and to stimulate the appetite; lemon juice, mixed with fruit juice of Emblica officinalis Gaertn (Euphorbiaceae), is taken to stop dysentery. In India a fruit poultice of Citrus sinensis Osbeck is applied in some skin conditions such as psoriasis.

A number of Citrus species have been used in traditional Chinese medicine.

The dry pericarp of the fruits of pomelo, C. retkulata Blanco (mandarin), ripe or unripe orange and C. medica L. is used mainly as an expectorant or stomachic; the pericarp of the unripe fruit of C. retkulata is used amongst other things in the treatment of hernia; the dry unripe fruit of orange and its cultivated variants and sweet orange are used in the treatment of diarrhoea, anal prolapse and frank prolapse; the seeds of C. retkulata Blanco (mandarin; tangerine) are used principally in the treatment of hernia ().

The dried fruit of orange is included among the antishock herbs used in the traditional Chinese medicine Tai-fu, which generally treated shock symptomatically. In Chinese folk medicine, this drug was commonly used to treat indigestion and to relieve abdominal distension and ptosis of the anus or uterus ().

While numerous effects of Citrus fruits are described in Medicinal Plants of China by Duke and Ayensu (), the orange fruit is antiemetic, antitussive, diaphoretic, digestive, carminative and expectorant, and can be used to treat abdominal pain, diarrhoea, chest congestion, cancer, hematachezia, rectal prolapse, rectocele, splenitis, stomach ailments, tenesmus, uterine prolapse. The seed and the pericarp are used for anorexia, chest pain, colds, coughs, hernia, orchitis and nausea, and can be crushed and applied to freckles and pimples. The pomelo leaf is boiled and placed on painful places and swellings and ulcers and is used as a depurative; the peel is antivinous, aromatic, bitter and stomachic and is used for boils, cholera, colds, dyspepsia, itching and nausea; the seeds cooked with pork or lllicium are used for bladder pain, hernia and swollen genitals. The sweet orange died peel is used for anorexia, cold coughs, malignant breast sores and phlegm.

According to Chinese tradition (), the not completely mature fruits (‘Zhiqiao’) of Citrus aurantium L., C. aurantium L. var. amara Engl. or C. Wilsonii Tanaka disperse stagnant vital energy, have an expectorant effect and act as a digestant. They are mainly used to treat excessive accumulation of phlegm, thoracic distress, distention of the costal region, dyspepsia, eructation, vomiting, dysentery with tenesmus, and prolapse of the uterus or rectum.

A short summary of the uses of Citrus species in East and Southeast Asia (India, China, Indonesia, Philippines) is given by Perry (). The rind or juice of fruit of various species are employed in the traditional medicine as a fragrant, stomachic, carminative, antiscorbutic, antiemetic, antivinous, diuretic and expectorant. A fruit peel decoction is used in coughs, colds, dyspepsia, as an antidote for fish poison, and in ointments on acne and eczema. Some juices (probably sour) are employed as a gargle for the treatment of sore, inflamed or suppurated throats and to cleanse or dress wounds. The leaves are considered to be sedative and antispasmodic, while a decoction of the leaves is applied hot to treat aches and swellings.

The sour (bitter) orange is used in Vietnam as a diaphoretic and purgative, in the Philippines as a food for the sick, particularly in febrile, inflammatory and scorbutic conditions ().

Essential lemon oil is held to have some value as an antibiotic ‘to treat typhus, meningo-coccus and other bacteria bacilli, but care must be exercised in its use, as too large a dose is stupefying’ ().

Citrus in traditional medicine of Africa

In Saudi Arabia the fruit of Citrus medica L. var. turung Bonavia is used for stomach-ache and fevers. A concentrated infusion of the fruit mixed with salt and honey is used against coughs ().

In Arabian medicine the juice, dried and fresh fruit, peel and bark of lime are used as remedies for cataracts, colds and fevers, chest pains and earache and as a stomachic.

A variety of sweet orange (safargal) cultivated in Oman and its fruit is considered a general tonic to improve the stomach, and eaten 2—3 times a day is used in treating jaundice. Smelling the plant or fruit of safargal is held to be good for the heart. In Yemen orange peel is eaten at breakfast mixed with milk to make the stomach strong and stimulate the appetite; fruit pulp is believed to strengthen the heart ().

The bitter orange is cultivated in North Africa. An infusion of the bark (fruit peel ??) is used for stomach pains and dysentery, the bark (fruit peel ??) as a digestive, antispas-modic, diaphoretic and mild sedative, and an infusion of the dried flowers as a nerve sedative and antispasmodic (hysteria, spasms, hiccups). Water distilled from the flowers is given to babies to calm them and help them sleep. An infusion of the flowers is stimulant and antidiarrhoeic ().

In East Africa () the root of lime is used as a snake bite treatment, to relieve abdominal pains, to treat gonorrhoea (as a decoction) and as an aphrodisiac (cooked with meat). The juice obtained from the leaves is squeezed into the ear for ear-ache.

In South Africa lemon juice is used with salt as a ringworm remedy, in the Transvaal with honey as a cough remedy and with ginger for a cold. Swahili women apply the juice to the vagina to produce contraction after childbirth ().

Lime leaves are a Malay remedy for headache, and the infusion is used for fevers with slight jaundice and bilious fever. The fruit juice is a cough reliever, a tonic and a remedy for stomach-ache and is used externally as a cleanser of and stimulant to wound surfaces. Roasted slices of lime are applied to chronic sores and yaws, but when applied to the skin followed by exposure to sunlight they produce a photodynamic reaction (). In West Africa () lime leaf preparations are used as a gargle and for treating pneumonia (mixed with a large number of other plants), malarial fever, fever and eye diseases (boiled with orange leaves), fever with jaundice, gonorrhoea (as a vapour bath), headache, bilious fever (with Ocimum leaves) and stomach-ache (with Areca catechu), and as a mouth wash. The rind of C. medica or C. acida is used against helminthiasis and the root bark of C. nobilis as an antirheumatic ().

In the traditional Senegalese Pharmacopoeia () a decoction of lime leaves is used as a drink for treating urinary retention and affections of the respiratory tract; the bark of the root, in the form of a decoction with twigs including leaves and seeds, is highly considered for its diuretic and antiblennorrhagic action. The fruit juice is used not only for aromatising, but also as a vehicle for numerous febrifuge and antidysenteric preparations, and is recommended for aphthae in children, etc.; the juice, after adding the essence, is used for massaging as an invigorating, febrifuge and sudorific agent and also an antiophidic remedy.

Citrus in traditional medicine of the New World

The above description of the uses of Citrus in traditional and popular medicine refers mainly to Mediterranean countries. After the discovery of America, cultivation of the most widely used Citrus species spread to the New World. There is documentary evidence of the presence of bitter orange plantations in Vera Cruz and in Mexico in the second half of the sixteenth century (), whereas a few years later (1568) in America there were plantations of lemons and sweet oranges (). Cultivation gradually extended to Florida, Louisiana, California, etc. and today the original naturalised species and the numerous varieties derived from them are so widespread throughout the United States that Citrus fruits have a place not only in the diet but also in traditional medicine.

In America the fruit, peel and oils of bitter orange and sweet orange are used as a carminative, aromatic and stomachic. Orange peel and oil are used as a flavouring in food, drinks and medicine and the juice as a source of Vitamin C. Lime fruit (C. Limetta Risso) is used more for flavouring than medicinally, although the juice is used as an antiscorbutic ().

In Mexico () the leaves of bitter orange (naranjo agrio) are used for their antispasmodic, tonic and febrifuge properties and in treating nervous excitation, palpitations and epilepsy. P. Font Quer (), in describing the virtues (virtudes) of the citron, lemon, bitter orange and sweet orange, re-examines the work of Dioscorides, and outlines the current use of the drugs obtained from these plants, the lemon in particular, stating that it ‘has countless esteemers and constitutes a panacea believed to cure an infinite number of illnesses’.

Morton () includes the mandarin (mandarin orange; C. reticulata Blanco) among folk remedy plants identified in Northern Venezuela. The decoction of the fruit peel is believed to have a hypoglycaemic effect while the peel is considered an antibiotic.

The lime (C. aurantifolia Swingle) has a multitude of uses in folk medicine throughout the tropics: the juice is taken to halt diarrhoea, it is considered an effective disinfectant in the eyes of newborn infants and for wounds, diluted in water, hot or cold, it is gargled for throat ailments and taken internally to relieve fevers, liver complaints and oedema; it also serves as a diuretic. In Yucatan the juice is used in diabetes, in rheumatism and in atherosclerosis and the leaf infusion serves as an antispasmodic, sudorific and sedative; the root decoction is given as a treatment for gonorrhoea. In Curasao lime juice is added to ‘tea’ of Cymbopogon citratus taken to relieve bronchitis. In Trinidad lime juice is used against thrush and toothache and also as a rub on erysipelas and is applied to the chest in the case of pneumonia; a ‘tea’ of flower buds is taken as a soporific and a root decoction is applied on scorpion stings. In Jamaica, lime juice mixed with the crushed fruits of Solanum aculeatum is said to cure ringworm. In the Bahamas the juice is used to repel mosquitoes and if one is bitten by these insects the juice will relieve the itching; the leaf decoction is used as a tonic and as a remedy for blood pressure ().

In Central America bitter orange juice is used as diuretic and purgative and as a remedy for coughs and fevers; a decoction of the peel is administered to relieve flatulence. The leaves are commonly utilised in folk medicine in the form of an infusion or decoction as a diuretic, cardiac stimulant and sedative and for reinforcing other remedies for fever (Yucatan), for treating gall bladder problems, hypertension and when the stomach is upset (Curagao), and in a decoction with Annona muricata leaves as a remedy for asthma, as a sedative and for promoting good sleep (Curagao). The decoction or essential oil of the leaves and flowers are considered antispasmodic; the fresh and dried flowers are used in a ‘tea’ as a stomachic and sedative; an ointment prepared from the flowers is applied on skin disease; the peel decoction is used to relieve stomach-ache and as a bitter tonic; the fruit juice is used as a remedy for colds and sore throat. The sweet orange peel decoction is a remedy for dysentery and intestinal worms and for flatulence. In Curagao a decoction of the peel is taken when one lacks appetite; the leaf infusion as an antispasmodic or in treating hysteria, palpitations, convulsions and epileptic attacks, in gastralgia and bronchitis. The Mayas in Yucatan use the leaves ‘tea’ as a sudorific. The ‘tea’ of the leaves is taken in Trinidad for pneumonia and as a depurative after child birth; the flower decoction is a popular sedative. In Ecuador an extract of orange seed is used in the treatment of malaria ().

In the Caicos Islands () at the southern end of the Bahamas chain, acid juice of the lime fruit (C, aurantifolia Swingle) or of the bitter orange is a remedy for typhoid, as they say ‘give plenty of sours’.

In the Amazonian Ethnobotankal Dictionary by Duke and Vasquez () it is reported that the decoction of lime root, taken a cup-a-day during the menses, is said to act as a contraceptive; the juice of one lime, taken by both partners just before intercourse, will prevent conception; lime peel is used as an antidandruff, decongestant and sedative; the flowers as tonic are used for cramps and enteritis. The lemon leaves infusion is a digestive.

On the strength of their continuing widespread use in medicine and pharmacy, the drugs obtained from the various species of Citrus are included in modern Pharmacopoeias ():

  • Citrus aurantium L. var. amara L.: Exocarp (flavedo), exocarp and mesocarp (bitter orange peel), flowers, leaves, fruit, unripe fruit, fruit essential oil, flower essential oil (neroli).
  • Citrus aurantium L. var. bergamia Risso: Exocarp (flavedo), fruit, exocarp essential oil.
  • Citrus aurantium L. var. dulcis L.: Exocarp (flavedo), exocarp and mesocarp (sweet orange peel), fruit, exocarp essential oil, fruit juice.
  • Citrus aurantium L. spp. natsudaidai Hayata: Exocarp and mesocarp.
  • Citrus medica L. var. limetta Risso. Fruit, exocarp essential oil.
  • Citrus medica L. spp. limonum (Risso) Hook f: Exocarp (flavedo), exocarp and mesocarp (peel), fruit, seed, flavedo essential oil, fruit juice.
  • Citrus medica L. var. vulgaris Risso: Exocarp and mesocarp, fruit, seed, flavedo essential oil.

Bergamot in traditional medicine

A short chapter is devoted here to a Citrus species that was introduced to Europe towards the end of the seventeenth century and has a habitat limited to a small area on the Strait of Messina: the bergamot.

The bergamot (Citrus bergamia Risso et Poiteau) is one of the cultivated forms of the Citrus genus along with the many other varieties of orange, lemon and citron. Its origin began to be a subject of discussion at the end of the eighteenth century. In his ‘Traite du Citrus of 1811, Gallesio notes that the plant has characteristics in common both with the orange and the lemon and therefore should be considered a hybrid of these two.

The bergamot, like other citrus species, was unknown to the ancient Greeks and Romans and was introduced to Europe many years after the citron, lime and orange. Like the other Citrus species already mentioned, the bergamot is a native of India, where the fruit was called Limbu in Punjabi, niboo in Bengali and neamboo in Hindi. In these regions it is still used against scurvy, dyspepsia and as an antiemetic, antipyretic and antiseptic.

There exist various theories regarding the origin of the name, the most likely of which appears to be from bergamot pear (deriving from Beg-armudi, which in Turkish means ‘the prince’s pear’), which the bergamot resembles.

It is not known with certainty when the plant first appeared in Europe. It appears to have been introduced as an ornamental at the end of the seventeenth century, but was first cultivated for the fragrance of its fruits towards 1750 around Reggio Calabria, later spreading to the Ionic and Tyrrhenian coasts.

The first reports of the presence of the bergamot in Europe date from 1693: in ‘he Parfumeur Francois’, printed in Lyon, it is indicated as Essence de Cedra ou Bergamotte, which according to the author, a certain ‘le sieur Barbe parfumeur , is obtained from the fruits of a Citrus species grafted onto the trunk of a bergamot pear.

In 1713 Volkammer of Nuremberg published a splendid book on the Citrus tribes entitled ‘Hesperides Norimbergenses’, dedicating a chapter to the himon bergamotta, which he called gloria limonum et fructus inter omnes nobilissimus, and wrote that the Italians obtained one of the finest of essences from this fruit.

Ever since the plant was introduced to Calabria, the essential oil obtained from the fruit was renowned in perfumery for its fresh, delicate aroma. However it was also widely used in the popular medicine of this region as a cicatrisant in treating burns or varicose veins, as a microbicide, analgesic, antipyretic and antiphlogistic, and in treating furunculosis, pediculosis and dandruff.

In countries where bergamot is processed, the workers extracting the essential oil of the fruits never exhibit suppuration of lesions even if the lesions are relatively serious or complicated by abrasion or considerable loss of blood.

In the second half of the eighteenth century, the volatile oil was added in drops to lime tea or coffee as an antimalarial agent and had long been used as an anthelminthic and in treating scabies. For internal use, it was used as a sedative in a dose of 2-5 drops. It was also administered in drops on a sugar lump against insomnia.

Country people still use it to alleviate toothache and to disinfect and cicatrise lesions inflicted while working the bergamot. A few drops in water of the essence itself or of a well-known brand of soap solution of the essence is used by women for washing in the first few days following childbirth.

Massaging with bergamot oil is an infallible remedy for chapped, sore hands and feet and chilblains in cold winter weather. One of the preparations for use against chilblains, to be rubbed in 3 times a day, consists of 6g of bergamot oil, 6g of mint oil, 2.50 g of camphor and 100 g of castor oil. This oil is considered so useful and precious that even today houses are seldom without a bottle.

The use of the bergamot oil in popular medicine was immediately extended to the official medicine of the times, right from when the plant was first introduced to Europe. According to Fluckiger and Hambury (1878), bergamot oil was already included in a list of medicaments in an apothecary shop in the small German city of Giessen, printed in 1688.

In Pharmacology treatises from the last century we find an entire series of uses of bergamot oil. It was used in pharmacy to improve the smell of medicinal ointments and unguents, to prepare tooth-powder, hair oils and cosmetic preparations, and as an ingredient in the so-called ‘smelling mixtures’. In medicine it was used on its own or in an alcohol solution or in other preparations for massaging in cases of chronic rheumatism, paralysis and weakness of the limbs; for internal use it served as a taeniacide. In 1805 a work, published in Messina by Calabro and Ansalone, described the balsamic virtue of bergamot essence in treating lesions.

Some of the popular uses of bergamot essence have been re-examined and their utility confirmed. In 1932 A. Spinelli (), provided an extensive in vitro and in vivo demonstration that it could constitute a new antiseptic for use in surgery. It could substitute a 10 per cent iodine tincture since two successive brush applications of pure essential oil were sufficient to sterilise a given portion of skin. Along with perfect asepsis, there was a complete absence of local irritation or symptoms attributable to absorption of the essential oil.

Corassini (), reporting the clinical results of a more than ten month long experimentation project, in sterile and non-sterile surgery departments under his direction, using a product based on natural bergamot essential oil, observed that the product not only had an excellent disinfectant action on wounds and sores, but also promoted keratinisation of ulcers, while it had no or very little harmful effect on healthy or inflamed tissues. He also observed that the oil prepared artificially, a procedure used in that period, did not have the same effects.

After further concordant observations, a number of surgeons began to use it in a 15 per cent alcohol solution, as a substitute for iodine tincture, for preparing the operating field and for medicating infected lesions. Although alcohol solutions are unstable, a stable aqueous soapy solution was successfully prepared. The antiseptic action of the essential oil is a result firstly of the presence of phenols, alcohols and aldehydes which act directly on germs, and secondly of the hyperemia and positive leukocytosis induced in the wound, which increase the organism’s defences. In 1935 G. De Nava confirmed that bergamot oil can usefully be applied in the field of odontostomatology since it has a marked specificity of action in the pathology of the tooth socket and an antiputrid power on roots with pulp gangrene or which are highly infected.

According to Maimone, who in 1940 tried it out on soldiers affected with scabies, the soapy solution cured all the patients treated, generally after 3—4 days of treatment.

In 1979 Ricci and Rovesti confirmed the efficacy of bergamot oil in treating furunculosis, acne and trichoses, since it reduces dandruff and hair loss.

Due to the presence of bergaptene, which has harmful biological effects such as photo-sensitisation, mutagenicity and carcinogenicity, good results were nonetheless obtained in the treatment of psoriasis as this psoralene blocks proliferation of skin cells and prevents them from whitening, which is a characteristic manifestation of the disease.

This fruit, whose bitter taste that reflects the harshness of the land for the people who inhabit it, encloses within its golden skin a strong but delicate fragrance, rich in beneficial virtues and offering hope of a cure.

Citrus as a current folk remedy in Mediterranean countries

In Mediterranean countries, we find that citrus species have an important place not only in the diet but also in self-medication. The lemon, in particular, appears to constitute a kind of panacea for all ills and many of its uses are based on popular beliefs, e.g. to treat ophthalmias slices of lemon are applied to the temples for a sufficient length of time to induce burning, in typhoid fevers roast lemon slices are applied to the forehead (Pitre, 1870). Other uses are found in traditional medicine and have a therapeutic purpose: 10 per cent bergamot essence in 70° alcohol as a local antiseptic; distilled water of C. aurantium var. dulcis L. and syrup of Capsella bursa pastoris as an antihaemorrhagic in menorrhagia during puberty and menopause ().

In cosmetics (), orange flower water, neroli oil and bergamot oil are ingredients in the formulation of colognes, perfumes and creams for dry skin (orange flower water). Massaging the face with lemon juice reduces hyperactivity of the sebaceous glands of greasy skin. Ten per cent bergamot essential oil in 70° alcohol, followed by an emollient mask based on starch and oil to reduce burning or cutaneous tension is useful in the treatment of comedones. Lemon masks serve to soften the skin. Our grandmothers used to rub slices of lemon onto the skin of their hands to keep the skin smooth and soft. A dry skin cream contains orange flower water, almond oil, cocoa butter, beeswax and an emulsifier.

Diced lemon is used in recipes for antiseborrheic baths. A mixture of lemon juice and avocado oil can be rubbed onto fragile finger nails.

In aromatherapy citron oil is used as an internal antiseptic; lemon essential oil incorporated with creams or milks can perform an antiseptic function in skin infections; it is a good antiseborrheic, helps prevent wrinkling and is soothing for the hands; orange flower water, the Medieval Aqua Nanfa, is well-known for its soothing, antiseptic, refreshing and deodorant action; sweet orange oil has a sedative action ().

In addition to preparations of Galenic forms, the above-mentioned Citrus species are included in numerous medicinal specialities from all over the world, not just as flavour and smell enhancers but also due to their vitamin C content, their bitter-tonic action and their antispasmodic effect.

The importance of the use of Citrus species in diet and traditional medicine is reflected in the widespread use of their images on postage stamps: the orange features on stamps from all of 30 countries (Albania, Algeria, Formosa, Cyprus, Gabon, Guinea, Honduras, Iraq, Israel, Italy, Jamaica, Lebanon, Montserrat, Mozambique, Pakistan, Paraguay, Rhodesia, Russia, Spanish, Marocco, Turkey, etc.). Fruits depicted on other country’s stamps are the orange and lemon (Algeria), the lemon (Gabon, Guinea, Lebanon), the lime (Dominica, Montserrat), the grapefruit (Honduras, Somalia) and the citron (North Vietnam) ().

In a critical reappraisal based on the most recent pharmacological research, several of the numerous therapeutic properties attributed to some species of the Citrus genus in the traditional medicine of the countries, where they have spread and acclimatised, have been shown to be well-founded and the active ingredients responsible for these activities have been identified. The anti-oxidant activity of anthocyanin, present particularly in pigmented oranges, has led to a revaluation of this generous gift of nature.

The golden fruits of the mythological garden of the Hesperides, the oranges of a bright red colour that reflects the fire of Etna, the inebriating perfume of the zagara (orange blossom), the white flowers that adorn brides, are the manifestation of the gifts brought to us by Citrus species: nutriment, beauty, health and poetry.

Do you know the land where lemon trees bloom,

where golden oranges glisten among the dark leaves?

(J.W. Goethe—Mignon, verses 1-2)


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