The amazing background and history of Sangre de grado and its uses are described in the following article.
Sangre de Drago
Lazaro Sánchez-Pinto (Director of Natural Science Museum)
Rafael Zárate (Researcher at Canary Islands Cancer Research Institute (ICIC))
On the morning of August 1, 1403, a small ship commanded by a Norman knight named Gadifer La Salle anchored in the Bay of Gando, a large natural harbor located between Telde and Agüimes, as described in Le Canarien, the French chronicle about the conquest of the Canary Islands. At dawn on the beach were gathered around 500 canaries carefully watching the movements of the barge and its crew. According to Pedro el Canario, the conversation or “discussion” that was on board, he suggested Gadifer to make some tradeoffs, which the Canaries agreed on with some distrust on both sides. The Chronicle adds that they brought them “lots of fig trees and dragon’s blood that changed by hooks, old utensils and sewing needles. The dragon’s blood trees were worth at least two hundred gold coins but what they got in exchange was worth no more than two francs”.
This is the first reliable historical information on the dragon’s blood of the Canary Islands.
Dragon’s blood in Ancient Time
The dragon’s blood was a famous and very popular product known in the past for its extraordinary medicinal properties attributed to him. Its origin, however, was unknown and remained shrouded in mystery for a long time.
An oriental legend tells the story of an Elephant and a Basilisk (a kind of dragon reptile or snake with legs and wings) facing each other in a bitter fight to the death. The basilisk penetrates into the elephants body and tears its skin with his claws and teeth. Blood loss weakens the elephant causing him to to fall precipitously to the ground, crushing the strange reptile. On its lethal agony, the blood of beasts both mixed and at clot, forms an amorphous mass that possess magical powers. This legend was cited by Pliny the Elder (first century AD) in his monumental Natural History, and subsequently spread throughout Europe. Pliny called it sanguis draconis, and that name appears in numerous Latin European medieval texts.
A similar version is in classical Arabic literature, where the protagonists are two brothers fighting each other, killing both in a bloodbath, al-ajawayn dam, meaning ‘blood brothers’, and so became known and marketed in the medieval Islamic world, including the Caliphates era of al-Andalus.
In reality, the true origin of the dragon’s blood was already known long before, but was kept hidden for pure economic interest. It should be clarified that it was not dragon’s blood of the canaries whose trade is much later (early fifteenth century), but the coming of the dragon of Socotra, an island off the Horn of Africa. In Erythraei Periplus Maris, a work of the first century AD that traces the journey of Greek sailors by the Arabian Sea, the island describes Dioscórida as the place they grow trees that exude a red resin called Cinnabaris. There’s no doubt its related to the species ‘Dracaena Dragos Cinnabari’ that is endemic to Socotra Island.
A fabulous drug
The Socotra dragon’s blood came to Europe with the spread of Islam from the eighth century, along with other famous plant products of the island, such as aloe (juice of plants of the genus Aloe), myrrh (resin shrubs of the genus Commiphora) and frankincense (resin from trees of the genus Boswellia).
Shortly after the Muslim penetration in the Iberian Peninsula these drugs could be bought in pharmacies in al-Andalus. The doctor al-Dinawari Granada (ninth century), author of a voluminous book on natural products, seems to confirm this: “I have been informed that the dragon’s blood (dam al-ajawayn) and myrrh (murr) brought from Socotra (Suqutra ) come with the bitterness socotrino (sabir suqutri) “.
Ibn Yulyul, another Andalusian physician who practiced in Cordoba in the tenth century, had heard that at Cadiz grew a tree that produced the drug: “There is some in al-Andalus, in the peninsula of Cadiz. That told me a greengrocer who saw with his own eyes, but not many, just a single tree”.
However, for al-Isbili Seville agronomist, author of a treatise on vineyards in the twelfth century, the true nature of the dragon’s blood was not clear: “There are different views on this, some say that al-ajawayn dam is juice of a plant that is more than just a resin of a tree, more than artificial compound.” The Arabs also marketed red resin obtained from several Southeast Asian palm of like properties of dragon’s blood.
Adding to the confusion, the plant from which the precious drug was obtained received different names, as Sayyan quoted by most physicians from Al-Andalus. Some thought it was a tree, other than a palm tree, while for others it was a succulent plant. Still in the thirteenth century, al-Baytar physicist, born in Benalmádena (Málaga), warned of imprecise Sayyan word meaning: “Note that in al-Andalus and commonly called the great sort of telefio”.
The “telefio” referred to by the author must be linked to crassulacean, one of the Iberian Peninsula, all distant relatives of the genus Aeonium verodes canaries. It is curious that in some locations on the island, it is called sayón candle plant.
With a mysterious origin and virtues so extraordinary, no wonder the dragon’s blood became a highly prized product in medieval Europe. Apart from therapeutic interest, were attributed magical properties and into the composition of potions, elixirs and even the philosopher’s stone. Their trade was extended, and in the thirteenth century it was known in France, probably through Arab merchants of al-Andalus. This is suggested by the text of the surgeon Henri de Mondeville: “Sanguis Draconis, the Arabic al-alkhwein dam, is the juice of a plant whose virtues are moderately hot and dry in the second degree.”
In medieval pharmacopoeia, medicinal plants were classified according to their activity on the four elements as classical philosophy, were the nature of all things: water, earth, air and fire. Thus, plants with virtues were cold and wet (water), cold and dry (land), hot and wet (air), and hot and dry (fire). It also indicated the degree, by varying therapeutic efficacy. For example, to treat a burn (hot and dry) had used a plant with antagonistic properties, that is, cold and wet, for flatulence (hot and humid), a cold and dry plant, etc. The aim was to restore the natural balance of the patient, as well as modern medicine aims. The difference is that they only treat the symptoms of the disease, not the source, which in most cases is unknown.
In that sense, there was no unanimous opinion among medieval physicians with regards to dragon’s blood. For some it was “cold and dry in the third degree” (al-Gazzar, tenth century of Salicet Guillame, XIII century), for others, “hot and dry in the second degree” (Henri de Mondeville, XIII century). In some areas like the Moroccan al-Gassani (XVI century), it was not clear: “cold and dry in the second degree” while others say “it’s warm.” It is possible that different views were due to the confusion about the origin: telefio gum resin, a palm Asian blood Socotra dragon or dragon that grow in the mountains of the Anti Atlas (Dracaena draco subspecies ajgal).
The medieval doctors recommended it, basically, to heal open wounds and regenerate damaged tissues, as well as an element in the composition of remedies for various diseases. Said al-Baytar summarizes its main virtues: “It is in the wounds of sword and similar weapons [...] short hemorrhages [...] heal fresh wounds and bleeding [...] constipated vagina [.. .] strengthens the teeth [...] is useful against abrasions from the intestines [...] is astringent [...] “.
To these medicinal properties were added many more, also allegedly extraordinary as its efficacy in the treatment of hernias, gonorrhea, sexual impotence and incontinence. In later centuries, the dragon’s blood remained on the major European drug treaties. In “The Herball”, a medicinal plant book written by the English physician John Gerarde in late sixteenth century, it was recommended in order to contain the flow against dysentery and strengthen teeth. John Parkinson, in his “Theatrum Botanicum” (1640), prescribed it in cases of gonorrhea, watery eyes and small burns. For the German physician Schroeder, author of a “Pharmacopoeia” (1698), it was a drug that was used for almost everything: “It refrigerativa, desicativa, styptic and repercussional if you put a plaster over the head, it cures catarrh, and for dysentery it should be placed above the navel; powder used to stop bleeding, strengthen gums and cures of rejuvenation and beauty. ” One of the most curious virtues attributed also was to restore virginity to girls who had lost it, “per the vergenitá of ragazze”, as stated in a XVII3 century Italian manuscript.
No doubt that the dragon’s blood, rather than a drug, is considered a real panacea.
Dyes, lacquers and varnishes
Its use as a red pigment found in ancient texts, although it is sometimes being confused with other substances, especially with minimum or cinnabar, which is a class of mineral sulphides rich in mercury. Pliny himself warned of the error: “There is no other paint color in the blood as it [...] but by Hercules! as doctors also called Cinnabaris which was used as a drug that was poisonous. ”
It appears that confusion in the writings of Iranian Jabir ibn Hayyan (eighth century), considered the father of modern chemistry, as it mentions both products, dragon’s blood (dam al-alkhwein) and cinnabar (isrinj), in the color of glasses. Nor is there in one of the most important technical treatises of the Middle Ages, De diversis Artibus Schedula, work attributed to the Benedictine monk Theophilus (XII century), which explains how the illuminators, glassblowers, jewelers, enamellers, etc., used the dragon’s blood or “basilisk powder” as the author calls it, remembering his legendary origin.
Modern techniques of chemical identification (chromatography, Raman spectroscopy, etc..) Have shown his old job in different objects of metal, marble, ceramic, wood, etc. According to some scholars, the dragon’s blood was used by Antonio Stradivari, the famous seventeenth century Italian luthier, to varnish his famous violins. It was a secret he never revealed, since supposedly helped to provide its unique sound. But this has not been proven, not least because of the difficulty in obtaining samples of these instruments as they are extraordinary. (4)
The dragon’s blood of the Canaries
According to tradition, the dragon’s blood was part of the Guanches ointments used in the mummification process, but so far there’s no archaeological evidence has been found to confirm this. No wonder that the Guanches knew its medicinal properties and employed to heal wounds or bumps and bruises, as its use in folk remedies continued after the conquest. It was also used to dye their skin and red coloring their shields of the drago tree bark or even to paint their bodies. But these practices are known only through indirect references that appear in chronicles antiguas. (5)
A mid-fourteenth century, the price of dragon’s blood was rising and trade was very profitable. And it is precisely at this time when first contacts were made between European sailors and modern aboriginals. The main benefit of these expeditions came from slaves, tanned and orchilla. (7).
It is clear that the aboriginals knew the rates for dragon’s blood among Europeans, and the proof is that in 1403 they had stored a lot of it, which helped them deal with the Normans. We do not know if it was common dragon’s blood (Dracaena draco) or endemic to Gran Canaria Drago (Dracaena tamaranae), since both species grew on the island. In any case, it seems clear that the canaries were unaware of their value and that the Normans made a deal: “dragon’s blood were worth at least two hundred gold doubloons, and all that was given was no more than two Francs worth” 7.
Jean de Bethencourt and successive owners of the islands under the Normans (manor Islands: Lanzarote, Fuerteventura, La Gomera and El Hierro) sought to gain a monopoly of their trade but ran into the interests of the Church, which soon wanted to participate in this lucrative business by demanding payment of tithe. A tax of 10% on the value of exported goods began as the European settlement was consolidated. In the sealed document promulgated by Eugene IV in 1434 it was ordered to pay tithe for “dragon’s blood, the orchilla, amber, shells” and other products of the exotic Islands. Either through related merchants clergy, feudal lords or the royal authorities, what is clear is that in the fifteenth century, the Canary Island’s dragon’s blood was already marketed in Europe and was competing with the Socotra and Southeast asia ones. (8)
There is no evidence that at that time drago trees were existed in the islands except La Gomera, which must had quite a number of them as described in Le Canarien: “The country is full of drago trees in large quantity.” It is likely that there were important colonies on the slopes of the great cliffs of the island where environmental conditions are optimal for their development. However, most of them disappeared within a few years by overexploitation to which they were subjected. It is currently believed that only a descendant of those early dragos of Alajeró survives in a ravine, contained in municipal heraldic shield.
In the early sixteenth century, when the islands had been conquered and regular business relations existed, exploitation of dragon’s blood intensified. Gran Canaria, Tenerife and La Palma, which were conquered under the auspices of the crown, harboring the largest colonies of Dragos, but suffered the same fate as those of La Gomera. The process of extracting the resin was influencing the decay of these trees as they suffered deep cuts in the trunk and branches with “a sickle or sword and putting it under a glass fall”, as reported by the Portuguese traveler Gaspar Frutuoso in the second half of the sixteenth century. Such wounds facilitates penetration of bacteria, fungi and especially insect larvae which feed on wood that poses the greatest threat to the stability of the dragos. (9)
In 1574 as a protective measure, the Cabildo of Tenerife agreed to ban his collection, under penalty of 100 lashes. But to no avail, as it continued to export massively to European markets. It was marketed in two forms: common blood, which was extracted by incision, and blood or tear drop, which is what the tree naturally exudes from small cracks in the trunk and branches, especially during times of heat. This was considered to be of higher quality and therefore was more expensive. (10)
At the end of the sixteenth century, most dragos had been bleeding endlessly. The same was happening in the Portuguese archipelagos of Madeira and Cape Verde, which also exported large quantities of dragon’s blood. The offer was much greater than demand, and prices plummetted. In 1595, a pound (460 g) of blood was sold for four quarters and a half, which was roughly the cost of a kilo of sugar, the main export of the Canaries. Since then, the business was no longer profitable, becoming a marginal economic activity. For dragos it was too late; their populations had been depleted and only few survived, mostly in inaccesibles cliffs. (11)
In the seventeenth century the resin was sent in small quantities to Europe, mainly through British companies which were trading with sugar, wine, and other products from the orchilla islands. A few were exported from Spain in the form of sweet sticks dipped in dragon’s blood which became fashionable as dentifrice among the upper classes of society. Lope de Vega, Tirso de Molina and other Golden Age authors mention the practice in some of their works, highlighting its effectiveness to clean and strengthen teeth.
The dragon tree of La Orotava and other old species that still existed in the eighteenth century were made famous in Europe thanks to many travelers in time. Most of the stories are embellished with fanciful descriptions about its antediluvian origin, the extraordinary longevity or veneration of the Guanches to dragon’s blood but barely mentioned as an old memory. Viera y Clavijo and other authors of that century lamented the lack of attention it received, a product so valued in the past, criticizing the apathy of the authorities to the indiscriminate felling of the few dragon trees that were still surviving. (12)
In the early nineteenth century only few farmers were using the resin in folk remedies, but it had virtually disappeared as a drug in modern medicine. However, many people still trusted its effectiveness as toothpaste. You could even buy it in some major cities said the French officer Bory de Saint Vincent (1803) in his comment about some members of his expedition which bought the resin in a convent of nuns at La Laguna, who claimed they “had a beautiful and fresh mouth”.
It is possible that selling the product came from the famous nuns of Seminar Drago, who barely survived in the garden of the ancient friary of dominicos. (13)
Later in that century, the dragon’s blood was considered to be an exotic item, not a commercial or medicinal value. It became a small comment in a few pharmacological treatises of the time as in the pharmaceutical plant treaty in 1893 where Dr. Gomez Pamo says: “To extract this resin incisions are made in the trunk, which then flows slowly in hot weather and is collected in a gánigo [...] extraction is always done on a small scale and with no commercial purpose”.
Dragon’s blood of the canary islands has the consistency of a whitish resin when it drips out of the tree. In contact with air the resin will harden and acquire its red color. In a solid state it is fragile, and when broken it forms a glassy flakes with glossy and almost translucent look at the edges. When crushed, it becomes a very bright crystalline powder which then turns sticky when tampered. It is tasteless and odorless at room temperature but when heated gently it becomes malleable and emits a pleasant odor. It does not dissolve in water but in alcohol.
Despite its fame only little was known regarding its chemical composition. However, in recent years there have been numerous investigations carried out which unraveled its complex composition and in which various chemicals were discovered heretofore unknown. By now they have identified more than 20 organic compounds like flavonoids, saponins and chalcones.(14)
Several of the isolated products have undergone different tests to understand their pharmacological properties and the results confirm many of the virtues traditionally attributed to the dragon’s blood. Flavonoids for example, shows an antioxidant activity, anti-inflammatory, antiviral and antiallergic, and a protective role against cardiovascular disease, cancer and other diseases. However, it was also found that in high doses these substances can backfire.
Diosgenin is a steroidal saponin that lowers blood cholesterol. It also has estrogenic properties that enhances the activity of female hormones which may explain the effectiveness of dragon’s blood in the treatment of menstrual and menopausal disorders, urinary incontinence, vaginal dryness etc..
Another saponin called ruscogenine has anti-inflammatory properties and has proven very helpful in relieving hemorrhoids. The Chalcone substance appears to be effective in treating prostate problems and combined with flavonoids it promotes the regeneration of the skin which is one of the strongest property of legendary dragon’s blood.
The dragon tree has a large and robust roots that serve to hold it to the ground and others that are small and thin through which enters water and nutrients they need to live. These feeding roots are covered with a thin orange rind that contains some of the saponins in the dragon’s blood at a higher concentration. One is the dracogenina, which has proved to possess antibacterial and antifungal properties. That may be the reason, among others, for recommending the chewing of dragon’s blood tree “rootlet” to preserve a “beautiful and fresh mouth” like the nuns of La Laguna. Another substance is the icogenina, which shows a potent cytotoxic activity against the cell line HL-60 in human leukemia. It has been determined that cell death is apoptosis, i.e. cancer cells fail to reproduce and decompose.
It should be clarified that the therapeutic applications of these substances are still in the experimental stage, but it is also true that the results of recent research have opened new possibilities. The dragon’s blood is a natural product that can be helpful on issues of interest to the society: rejuvenation, antioxidants, leukemia, heart disease, prostate, menopause, etc.. In fact, the composition contained in regenerative creams, sunscreens and other cosmetic items that are not sold, but have already been patented recently just a few months ago. (15)
If demand increases and strengthened in the coming years, we must remember what has already happened five centuries ago, when most of the dragon disappeared due to overexplotation. Could intensive cultivation of dragos become the alternative to bananas? Being cost-effective, there is no reason to rule out that possibility. The dragon require much less water and thrive in the same areas as the banana. They are long-lived, but are growing rapidly and in a few years may be producing acceptable amounts of blood (resin). Similar cases exist in the Canary Islands such as Aloe vera, which is now cultivated in several islands with very interesting results.
Other “Dragon’s Blood”
Today, as in antiquity, the name “dragon’s blood” is still quite confusing as it applies to various plant resins that grow in different regions of the planet and belong to the same botanical family. This is mostly of red blood resins that exhibit certain common pharmacological properties, especially in regard to its healing action. Although there is no unanimous opinion, the “ancient” dragon’s blood is considered to be the one that was known before the discovery of America including the Canary Islands. The “new” has its origins in the New World and, at present, is the most widely used in medicine, especially homeopathy.
The “ancient” dragon’s blood comes from two types of monocot plants: tree species of the genus Dracaena family of Ruscaceae and rattan palms of the genus Calamus Daemonorops of the Arecaceae family.
Dracaena species are producing D. draco (Madeira, Canary Islands, Cape Verde and Morocco), D. tamaranae (Gran Canaria) and D. cinnabari (Socotra). There are other lesser known species (D. schizantha, D. and D. ombet serrulata) which are distributed in semi arid mountainous regions around the Red Sea. Probably also been exploited for their blood, but little is known about it.
Another ancient dragon’s blood, sometimes called draconis resin, is obtained from the fruit of several genres of Daemonorops palms and Calamus, which grow in the rainforests of Southeast Asia. Its current world production is estimated at about 50 tons per year, which mostly come from Indonesia, where it is exported to markets in Hong Kong, Singapore and Pakistan. Its fate is uncertain, since from these markets it is forwarded to other places. It is likely to be used mainly as a varnish in the booming Asian furniture industry and to a lesser extent as a drug in traditional medicine. Its therapeutic properties are similar to those of the sanguis draconis: bumps, sores, bleeding gums, dysentery, menstrual irregularities, impotence, etc.(16)
The “new” dragon’s blood comes from Latin, and is obtained from several species of the Croton and Jatropha from the Euphorbiaceae family, and the genus Pterocarpus of the legume family. The different varieties were used by American Indians and were incorporated into the Western pharmacopoeia after the discovery of the New World. So given the same name, although sometimes with variations such as “Sangre de grado”, “Sangrado” or “Sangregado”. Names that apply equally to the plant and the product.
The extensive literature on the dragon’s blood, from the different ancient texts and medieval treatises to the latest scientific articles, shows a huge interest in correctly identifying the origin and nature of the similar plants. This is interpreted not only as an honest and serious attitude of the authors, but also as the dire consequences that could lead to a false identification of a therapeutic product. People today still rely on the properties of any legendary dragon’s blood, many scientifically proven, and we recommend that which Pliny said two millennia ago.
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- Torriani, Leonardo. Descripción de las islas Canarias. Santa Cruz de Tenerife: Goya Ediciones, 1978.
- Viera y Clavijo, José de. Noticias de la historia general de las islas Canarias. Santa Cruz de Tenerife: Goya Ediciones, 1967.
- Viera y Clavijo, José de. Diccionario de historia natural de las islas Canarias. Santa Cruz de Tenerife: Imprenta Valentín Sanz, 1942.
1 La presencia en Cádiz de ese árbol ya había sido mencionada mil años antes por el geógrafo e historiador griego Estrabón, en su descripción de la Península Ibérica: “En Gádeira (Cádiz) hay un árbol cuyas ramas se doblan hacia el suelo y sus hojas, a veces de un codo de largo y cuatro dedos de ancho, tienen la forma de una espada… Si se corta una rama exuda leche, si es una raíz, destila un jugo de color rojo”. Por la descripción no parece que se trate de un drago, pero hay que tener en cuenta que Estrabón no lo había visto personalmente, sino que se basó en los escritos de Posidonio, un autor griego que lo citó casi un siglo antes. Por otro lado, no se puede descartar que en esa época aún existieran dragos salvajes en algunas localidades concretas del sur de la Península Ibérica, testigos supervivientes de una flora desaparecida del continente europeo durante la última gran glaciación. En cualquier caso, es curioso que Cádiz se haya conocido tradicionalmente como la “ciudad de los dragos”, y buena prueba de ello son los hermosos ejemplares –algunos de ellos varias veces centenarios– que hoy en día crecen en muchos parques y jardines de la “tacita de plata”.
2 En 1995 se descubrió una importante colonia de miles de dragos en una abrupta región del macizo del Anti Atlas, en Marruecos. El drago del Atlas se conoce localmente con el nombre bereber de ajgal, que significa ‘inalcanzable’, debido a que crece en paredones escarpados y de difícil acceso, incluso para las cabras. Se considera una subespecie del drago común, de ahí su nombre científico: Dracaena draco ssp. ajgal. Los dragos silvestres que crecen en el Peñón de Gibraltar también pertenecen a esta subespecie (Cortés, 1994). Por allí desembarcaron las primeras tropas musulmanas que invadieron la Península Ibérica a principios del siglo VIII. Más información sobre la sangre de drago en tratados árabes medievales en: Llavero Ruiz (1990), Cabo González (1995) y Cabo González & Bustamante Costa (2000-2001).
3 Becciani, Ugo. Un manoscritto pistoiese di “secreti” del tardo ’600: lettura critica e commento. Pistoia: Il Papyrus, 2000. (Resumen disponible en la red).
4 Sobre el empleo de la sangre de drago en técnicas artísticas, se recomienda el excelente trabajo de Pilar González Araña: Análisis de la resina sangre de drago: técnicas y procedimientos artísticos, que se puede consultar en la red (http://dialnet.unirioja.es/servlet/tesis?codigo=1029).
5 Una bolita de sangre de drago (17 mm de diámetro) apareció en una cueva de habitación guanche, en La Orotava, junto a lascas de obsidiana (tabonas), huesos de animales y fragmentos de cerámica aborigen. (Lorenzo Perera, 1977). Sobre su empleo por los guanches, ver Bethencourt Alfonso (1991-1997), Bosch Millares (1962), Oliva Tacoronte (1982).
6 Entre esos contactos destaca la expedición a las islas realizada por el capitán genovés Nicolás de Recco en 1341, al mando de dos naves proporcionadas por Alfonso IV, rey de Portugal. Entre otras mercancías, a su regreso trajo “palo rojo para tinte, corteza de árboles para teñir de rojo, tierra bermeja y otras cosas para el mismo fin”. Es posible que alguna de esas otras cosas fuera sangre de drago, pero no lo sabemos. En Europa, los pigmentos rojos eran muy cotizados en aquella época, de ahí su gran interés comercial (Millares Torres, 1977-1981).
7 La equivalencia actual de una dobla de oro de esa época es difícil de establecer, porque entonces coexistían doblas de oro de diferente valor y procedencia (castellana, francesa, árabe). Sin embargo, en otros capítulos de Le Canarien aparecen referencias que permiten, por comparación, tener una idea de su cotización a principios del siglo XV. Por ejemplo, cuando Jean de Bethencourt, el socio de Gadifer, abandonó las islas y regresó a España en busca de más apoyos económicos y materiales para concluir la conquista de Canarias, unos mercaderes de Sevilla le ofrecieron 1.500 doblas de oro por su nave, pero él no aceptó. En otro capítulo se dice que con el sebo y las pieles de las focas monje de Isla de Lobos se podía obtener un beneficio anual de 500 doblas ó más. Esto es, en un solo intercambio comercial, los normandos ganaron casi la mitad de lo que podrían obtener de las focas en todo un año, y si hubieran realizado siete u ocho trueques similares, podrían haberse comprado un barco.
8 Se podía adquirir incluso en las principales ciudades mercantiles italianas, que tradicionalmente importaban sangre de los dragos de Socotora, como refleja el Riccetario florentino (1498): “Sangue di drago é una gomma di un albero che nasce nelle isole Canarie”. (Resumen disponible en http://www.edicolaweb.net/am_1030.htm).
9 El drago también fue objeto de otros aprovechamientos que, sin duda, contribuyeron a la merma de sus poblaciones. Por ejemplo, en 1501, apenas cinco años después de concluida la conquista de Tenerife, se ordenó que los soldados estuvieran equipados con escudos de drago “de un grosor de un pulgar y no menos”. En un acuerdo de 1513 y por temor a una invasión francesa, el cabildo extendió esa orden a todos los vecinos entre 18 y 60 años, aclarando que los escudos debían tener “a lo menos de tres a cuatro palmos de ancho”. También los troncos fueron aprovechados para hacer colmenas o corchos, que eran muy valorados a tenor de sus frecuentes menciones en los acuerdos del Cabildo de Tenerife y los protocolos notariales del siglo XVI.
10 Los envíos de particulares eran frecuentes y solían superar los 100 kilos de peso. Por ejemplo, en 1557 Francisco Rodríguez, que tenía un negocio de joyería en Tenerife, había conseguido reunir 242 libras de sangre común y 13 libras y tres cuartos de sangre en gota, que envió a Lisboa en un solo cargo (Cioranescu, 1977). Una libra equivale a 460 gramos.
11 Según Gaspar Frutuoso, a finales del siglo XVI la mayoría de los dragos de La Palma sólo se encontraban “en lugares ásperos y tan abruptos que parece imposible llegar donde están, pero también van y cogen de ellos una goma tan roja como la sangre, que llaman sangre de drago”.
12 “Pero el ningún cuidado que se tiene de multiplicar tan hermoso árbol, ni el poco dolor con que se han ido cortando los que había, ha hecho escasear mucho un ramo de cosecha, de que se podría sacar notable utilidad”. (Viera y Clavijo, 1942).
13 “La mayor parte de los viajeros de nuestra expedición adquirieron en La Laguna, en un convento de monjas encantadoras, unos pequeños paquetes con raicillas que no tenían ningún sabor ni propiedad en sí mismas, pero que estaban coloreadas con resina de sangre de drago, con el propósito de masticarlas para fortificar los dientes y las encías. El mejor elogio que puede hacerse de esos pequeños productos, es que las religiosas que los vendían, tenían la boca fresca y hermosa” (Bory de Saint Vincent, 1803).
14 Gran parte de los análisis realizados hasta la fecha se han llevado a cabo en Canarias, por equipos científicos encabezados por el Dr. Antonio González y, más recientemente, por el Dr. Jaime Bermejo (Instituto de Productos Naturales y Agrobiología, CSIC, Instituto Universitario de Bio-Orgánica “Antonio González”, Instituto Canario de Investigación del Cáncer, Museo de Ciencias Naturales de Tenerife).
15 “De la presencia de sapogeninas, especialmente la ruscogenina y de isoflavonas en la composición de la sangre de drago se derivan de forma sorprendente propiedades antioxidantes para las células, lo que conlleva, cuando las células son epidérmicas, efectos regenerativos de la piel si se aplica vía tópica y, cuando se ingiere en forma de bebidas, alimentos o aditivos nutricionales o dietéticos, una menor muerte celular, lo que conlleva efectos antidegenerativos y antienvejecimiento del organismo y un efecto general vigorizante y tonificante en general” (parte del texto de varios productos patentados en 2009 en la World Intellectual Property Organization: (WO/2009/063105) Use of extracts of Dracaena draco in the preparation of pharmaceutical, cosmetic, dietetic and nutritional products). WIPO: http://www.wipo.int/portal/index.html.en
16 Para más información sobre el comercio mundial de la sangre de drago y otras resinas de origen vegetal, pueden consultarse documentos de la FAO disponibles en la red: http://www.fao.org/docrep/v9236e/v9236e00.htm.