Herbs in History: Licorice
Glycyrrhiza glabra L.
The Sweetness of Horsemen
When talking about licorice in the United States we might not have a direct hint at any way of administering the plant in medicine, whereas in the United Kingdom we would think of some juice thanks to the spelling liquorice that might evoke a liquor or, at the very least, a liquid. However suggestive the association of words and ideas might seem, it does not reveal much about licorice/liquorice and its most specific property: sweetness.
Going back in time up to classical antiquity, licorice was the sweet root par excellence as its ancient Greek name indicates: glukuriza, exactly meaning the sweet (gluku) root (riza). Carl Linneaus (1701-1778) knew his classics and used this Greek term to name its genus as Glycyrrhiza in his taxonomical system. In so doing, he was not the first, however. He was following his Renaissance predecessors, from the German Leonhart Fuchs (1501-1566), himself followed by the Belgian Rembert Dodoens (1516-17-1585), whose work was translated into English and became the famous Herbal by John Gerard (1545-1612). Interestingly, however, all this Pre-Linnean Renaissance tradition was not original either, as it was deeply rooted in a tradition going as far back as the beginning of our era.
Before that and going further back in time, the first mention of licorice in the Mediterranean tradition can be found in the treatise Diseases of Women attributed to Hippocrates and dated to mid-5th century BCE. Licorice appears in a short formula quite unique in the Mediterranean tradition, in a post-partum context, for expelling the placenta. It is mixed with honey and rose or Egyptian perfume and applied on the cervix in a tampon made of wool. The part of the plant to be used is not indicated. However, in some variants of the text, the name of the plant is not glukuriza—that is, the Greek classical name of licorice—but glukeie riza, literally meaning the sweet root in a designation that might hint at a limited knowledge of the plant just identified by its gustative property.
The next text mentioning licorice in a chronological sequence provide information that my contribute to explain this possible limited knowledge. This text is the Historia Plantarum (Research on plants) by the Greek philosopher and scientist Theophrastus (ca. 371-287). There we read that licorice is called the Scythian plant, that is, a plant typical of the Scythian population, which grows, still according to Theophrastus, in a region close to a lake that he calls Maiotis.
Illustration 1: The region inhabited by the Scythians in Antiquity.
This passage is less obscure that it might seem, being typical of the geography and ethnography of the Greek world at that time. The Lake Maiotis is the Sea of Azov, to the east of Crimea, in which flows the river Don. The Scythians, as for them, were an equestrian nomadic population of Eastern Iranian origin who migrated from Central Asia to a region corresponding to present-day Ukraine and Southern Russia from the 7th century BCE on (Illustration 1). They were not well known to the Greeks. The historian Herodotus (ca. 484-425 BCE) briefly described them, crediting them with such habits as inebriating themselves with cannabis smoke in funerals.
While this reference to the Lake Meotis characterizes a region toward north, at the limit of the world known to the Greeks, which was supposedly cold, foggy, and also marshy in the delta of the Don, the reference to the Scythians evoked a population qualified as barbarian by the Greeks, that is, a population without the history and culture of the Greek World. Quite the opposite of the natural and cultural world of the Greeks, characterized by a warm and dry climate, and an advanced culture. Knowing this, we can understand why the plant was not well known at Hippocrates’ time: it did not pertain to the Greek universe. By contrast, medicinal uses of licorice were known to Theophrastus. The well-known passage from his Historia plantarum is worth citing in full:
The Scythian [plant], too, is sweet (glukeia in classical Greek). Some even call it simply glukeia [the sweet one]. It grows in the region of the [Lake] Maiotis. Its is helpful against asthma, dry cough, and generally for all the ailments of the chest. It is also good against wounds, with honey.
It can also quench thirst if one holds it in the mouth. The Scythians have the reputation to spend eleven and twelve days [without eating and drinking] thanks to it and a cheese made of mares’ milk.
The most significant part here is the second, about Scythians’ alimentary usage and use of licorice. For the Greeks, accustomed to have a great variety of fresh vegetables and fruits in meals often accompanied by wine and sometimes also by music, this was quite a barbarian usage. In fact, it was of a population of horsemen, warriors, trained to spend long nomadic periods on their horses without always having access to food sources and possibly not even to fresh drinkable water. Stocks of licorice roots prepared before departure and kept in their bag and the milk of their horses were the only available food. All the opposite of the Greek food culture of that time.
It might seem curious that Theophrastus does not mention the part of the plant to be used. In fact, this mention of licorice appears in the chapter of the Historia Plantarum devoted to the roots with a special taste, the first two of which (waterlily and licorice) are sweet, while the next ones are bitter. The sole adjective sweet (glukeia) was enough to unmistakably identify the plant.
The therapeutic applications mentioned by Theophrastus were mostly for the respiratory system in ways that are not specified but can be expected to have been in internal use, with also a vulnerary use with honey similar to the Hippocratic gynecological formula.
With the passing of the centuries, licorice became better known. In the first century CE both the Greek Dioscorides and the Latin Pliny (23/24-79 CE) provide relevant information.
From the Hippocratics and Theophrastus to the first century CE, however, the Mediterranean world went through a sequence of transformations that are significant for licorice. After the zenith of classical Greece and Athens, Alexander the Great (356-323 BCE) expanded the Greek world to the East, up to India, exploring regions thus far unknown to the Greeks. At his death, his empire exploded in a myriad of kingdoms, among which that of Pontos, located south of the Black Sea (identified as The Sea—Pontos—in ancient Greek) in the northern part of current Turkey and extending deeply in Asia Minor. Then came Rome, its conquest of the East and its fierce war against the kingdom of Pontos, concluded in 63 BCE with the defeat and death of king Mithridates (b. 132 BCE), which gave access to the land of licorice to the Roman World of that time.
Returning to the first century CE, Dioscorides provides in De materia medica a great many details about licorice. First the names: Scythion, Pontic root, and adipson. If Scythion recalls the Scythians of Theophrastus, Pontic root is a reference to the Black Sea, probably not the Kingdom of Pontos, but rather the land inhabited by the Scythians. The apparently incomprehensible adipson is less mysterious than it seems: it means unthirsty and clearly evokes the use of licorice by the Scythians mentioned by Theophrastus as a substitute of drinking. Pliny reports this name, going further, however, and stating that licorice “... allays hunger and thirst ...”.
Judging from the locations mentioned by both Dioscorides and Pliny, the distribution of licorice expanded from Theophrastus’ time to the 1st century CE. Whereas Dioscorides mentions its abundant presence in Pontos and Cappadocia, that is, north and central Asia Minor (or current Turkey), Pliny states that the “finest species” comes from Cilicia, south-east of current Turkey. Both this location and the reference to a better quality suggest a cultivation aimed to improve the species.
Illustration 2: Glycyrrhiza glabra L. (Kerrick/Getty Images)
If Dioscorides describes licorice in a way that does not leave room for doubt on the identification of the plant mentioned in the ancient texts as a species of Glycyrrhiza (Illustration 2), Pliny does not provide any elements of botanical description.
As for the therapeutic uses, Dioscorides and Pliny mention only the root, described as sweet, with a dark yellow color similar to that of boxwood, and producing a juice extracted in the way dyers used for buckthorn (Rhamnus cathartica L.) according to Dioscorides.
Both Dioscorides and Pliny concord on most of the applications of licorice, with the first and most important being the use of the fresh root “for hoarseness of the trachea ... placed under the tongue to melt it” as per Dioscorides’s exact terms. It is “good for the mouth when chewed”, and treats buccal sores and wounds, in different forms: the fresh root or, according to Pliny, as a paste made from the root or as a thick decoction of it. For both authors, the root relieves from thirst, and, for the sole Pliny, this action recommends the use of licorice in cases of dropsy “to prevent thirst”. The other indications of the root in internal use, be it fresh, in a decoction, or in a decoction “reduced to the consistency of honey” are the following by major physiological systems:
digestive system: heartburn (the root administered orally with grape syrup), liver ailments, itching of the bladder, and pain in the kidneys;
respiratory system: chest pain;
intestinal system: anal tumor, according to Pliny;
genito-urinary tract: sores of the genitals.
In external use, a paste of the root or a powder made of it finely ground “is good for wounds”, being hemostatic as per Pliny, and for inflammations of the eyelids.
To this body of uses, Pliny adds a gynecological application as a pessary that recalls the Hippocratic formula, with the root “boiled down to one-third”; the treatment of malaria, in the form of a draught with pepper taken with water; and the expulsion of bladder stone according to “some authorities”.
Fits & Starts
The concordance of Dioscorides and Pliny reveals an effort to optimize the therapeutic uses of licorice and to expand the range of its applications. A clear sign of this could be the indication in cases of dropsy, which could result from an abstract speculation that licorice would be good to reduce the intake of water and contain by way of consequence the swelling of the body resulting from water retention. This possible effort to expand the range of therapeutic applications might be part of a more general project of domestication of licorice that also included cultivation and improvement of the species, as we have seen from Pliny’s text.
Strangely, the resulting body of data, which made a complete monograph comprising the description of the plant and the enumeration and description of its therapeutic uses, did not transmit completely in the subsequent centuries. As early as the 2nd / 3rd century, Galen (129-after [?] 216 CE) repeated that licorice was used for the treatment of the upper respiratory system and alleviated thirst, also explicitly quoting Dioscorides about the treatment of eyelids. To that he added speculative considerations on the qualities of licorice made of heat and moisture in balanced proportions that correspond to those of the human nature.
In the Arabic World, ibn Sina (Avicenna, 980-1037 CE) just repeated Galen’s information in the Qanūn, whereas ibn Butlan (d. 1066) did not mention licorice at all in his Taqwīm as-sihhah, better known through its Latin translation as Tacuinum sanitatis (Tables of health).
In the West, the tradition about licorice was tenuous, but not interrupted. In the Middle English text known as Macer Floridus, De viribus herbarum (On the properties of plants), a chapter is devoted to licorice. It starts with the clearest statement that “Liquorice is swettest of alle herbes”. In a simple, almost formulaic way, it lists its uses “for the brest, for the lunges and for the stomak”.
Illustration 3: John Gerarde, The Herball of Generall Historie of Plantes. Imprinted ad London by Iohn Norton, 1597, p. 1119: Of Licorice. Chap. 10.
It was the merit of the later, 13th-century, medieval medical literature to reintegrate licorice into the Mediterranean corpus of materia medica. The Tractatus de herbis (Treatise on medicinal plants) is revealing of a consolidated use of licorice as it devotes a long part of the chapter to its preparation:
... the fresh root, is well ground, well boiled in water, and left boiling until water is evaporated; it is pressed, exposed to the sun and dried, and given the shape of small round mass as per the shape of the recipient. Some people sophisticate the preparation as follows: they make a fine powder, they mix this powder with juice of licorice and boil the whole in water, they add honey and shape them as we said ...
Pursuing with the therapeutic applications:
... Its decoction in water is efficacious against any problem of the chest, in pleurisy and peripneumonia. Wine made of its decoction is efficacious against cough. An electuary made of the juice of licorice and honey is efficacious against the same. Chewed and held under the tongue, licorice calms thirst and stomach and throat coarseness.
Once better assimilated in the medieval therapeutic practice, licorice was also introduced in the Latin version of ibn Butlan Tacuinum as-sihhah (Tables of health) whereas it was not present in the original Arabic version. Unsurprisingly, it can also be found in the illustrated herbals of the Renaissance, by Fuchs, Dodoens and Gerard (Illustration 3) referred to above. Since these were mostly translations of Dioscorides and Galen’s Greek text, they returned to the origins, closing the circle.
The Revenge of the Scythians
Modern research is validating ancient uses from water retention justifying the Scythians’ chewing of the root instead of drinking, to the Hippocratic post-partum application possibly aimed to avoid puerperal inflammation. And, on the sweet side, in 2018 the so-called Liquirizia di Calabria was officially recognized by the European Commission as a Protected Designation of Origin “reserved exclusively for fresh or dried liquorice and its extract. This liquorice must come from cultivated or wild Glycyrrhiza glabra plants (family: Leguminosae), specifically the typica variety known in Calabria as Cordara”. Dioscorides wound not have disavowed its organoleptic description:
Illustration 4: Licorice from Calabria
When released for consumption ‘Liquirizia di Calabria’ PDO must have the following characteristics:
colour: straw yellow;
flavour: sweet, aromatic, intense and lasting;
colour: straw yellow to ochre yellow;
flavour: sweet, fruity and slightly astringent;
colour: dark terracotta brown to black;
flavour: bittersweet, aromatic, intense and lasting;
The sweet root vindicated the Scythian horsemen (Illustration 4).
Literature (articles, selection, chronological order)
European Commission on Liquirizia di Calabria
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