From - www.cropwatch.org
Copyright © Tony Burfield July 2005
The term ‘Dragons Blood’ refers to reddish resinous products (usually encountered as granules, powder, lumps (“cakes”), or sticks (“reed”) used in folk medicine as an astringent and for wound healing etc., and in other applications for colouring varnishes, staining marble, for jewelry and enameling work, and for photo-engraving. Mabberley (1998) suggests Dragons Blood was produced originally from Dracaena cinnabari, later from D. draco and more recently from Daemonorops spp.; Zheng et al. (2004) confirm this view and suggests substitutes for Dracaena spp. include Pterocarpus spp., Daemonorops draco and Croton spp.
Few commodity dealers properly distinguish the various botanical origins of Dragon’s Blood items, and over-exploitation is starting to threaten some sources – here is a brief guide.
Dracaena species (Fam. Dracaenaceae / Convillariaceae / Ruscaceae).
Dracaena cinnabari Balf. F. (exclusively from Socotra island, Yemen).
Dracaena draco (from the Canary Islands – esp. La Gomera- & Madeira).
The Dracaena genus includes some 60 tropical shrubs & trees. Dragon’s Blood (“Zanzibar drop”) originated from Dr. cinnabari, and Mabberley notes that this source of resinous sap produced via incisions in the bark or stem of the tree was used by the Ancients to stain horn to resemble tortoiseshell. Interestingly, resin from Dr. cochinchinensis has been produced by infection with Fusarium and Cladosporium spp. (Wang et al. 1999). According to the BPC 1911, the main producing country for Dr. cinnabari was Somaliland (Socotra is actually west of Somaila), and was distinct from Sumatran Calamus draco (see below) in being present in scales rather than tears, and not giving off benzoic acid when warmed. Over 50 endemic plants on the Socotran Archipeligo are listed on the IUCN Red list and the area has been described as vulnerable to increased human activity and tourist and industrial development by WWF - see http://www.worldwildlife.org/wildworld/profiles/terrestrial/at/at1318_full.html.
Edwards et al. (2001, 2004) have since described a Raman spectroscopic method for distinguishing Dragon’s Blood commodities of various botanical origins. Dr. draco growing in the arid areas of the Canary Islands can grow from 12m. to 19m. with a girth of 12m., but was described in the BPC 1911 as not being an article of commerce.
Phenolic compounds from Dr. draco have been described by Gonzalez et al. (2000).
It is not believed that resin from these sources (Canaries, Yemen) are commercial items, although a handful of internet websites dealing in incense items offer “rare” Dragons Blood from La Gomera (Canary’s).
Daemonorops species (Fam. Palmae).
The term "Dragons Blood" also refers to the resin layer on the surface of fruits of the climbing palms of the Daemonorops genus found in SE Asia, and often sold out of Sumatra, Malaya & Borneo, especially Sumatra which was once considered the superior source. This layer is descried as hard, imbricate scales (Trease & Evans 1978). The botanical source was previously identified as Calamus draco Willd. by Barry et al. (1926), who also described the resinous layer as being isolated by placing the fruits in sacks and pounding them, the pulp being treated with boiling water. Subsequently the resin was kneaded into balls or long sticks. The authors also describe an inferior grade obtained by boiling the fruits in water, and isolating the resin as a paste from the surface of the water (the lumpy residue, which also contains resin was also marketed). These lumpy resinous products are mainly composed of diterpene acids, and were mostly sold as violin vanish, and have also been used extensively to colour essential oils dark red/brown-red. The following species have been exploited for ‘Dragons Blood’:
Daemonorops draco Blume
D micranthus Becc.
D. motleyi Becc.
Pearson has reviewed Dragons Blood items from this and other sources (Pearson 20xx). Medical uses of D. draco include use as astringent, and in diarrhoea. Hsu et al. (1996) gives the actions of D. draco in Chinese medicine as controlling bleeding and pain, invigorating blood circulation and promoting tissue regeneration, noting its’ use in incised wounds and contusions etc. Hsu (1986) also gives the composition of D. draco as consisting of red pigments: dracorubin and dacorhodin; of resins: including dracoalban and dracoresene and red pigments: including dracoresinotannol. Some of this information appears is exactly identical to that published by Dietrich (1920). Trease and Evans (1978) note the diterpene acids as consisting of pimaric, isopimaric, dehydroabietic acids possibly quoting from Piozzi et al.’s original findings (Piozzi et al. 1974).
Croton species (Fam. Euphorbiaceae).
‘Dragons Blood’ here is a botanical usual seen as a lumpy dark red resinous material, produced from a number of Croton species:
Croton draconoides (Muell.) Arg.,
Croton draco Schlect,
Croton lecheri L.,
Croton urucurana Baill.
Croton xalapensis HBK.
Of these sources, C. lecheri is possibly the best known, the tree growing in Mexico, Venezula, Eucuador, Peru and Brazil. The sap (really a red-blood latex) of (Croton lecheri) is known as Sangre de Drago and a proanthicidin polymer from Croton spp. is the basis of a patent taken out by Shaman Botanicals, San Francisco (Rozhon et al. 1998) to make an anti-diarrhoeal medicine, the mechanism of which, involving the prevention of excess fluid secretion into the intestinal tract, was investigated by Gabriel et al. (1999). Shaman Pharmaceuticals also hold a patent on polymeric proanthocyanins as dietary supplements (Sesin et al. WO0047062). Other traditional uses for this source of Dragons Blood include antiseptic and GI calming functions. Wound-healing attributes may be connected with taspine, a cytotoxic alkaloid found in the leaves (Itokawa 1991).
Due to the high demand both internally and externally, Croton species (Dragons Blood) were amongst the 22 species identified in the Workshop of Specialists in Ethnobotany and Economic Botany held in 1997, as potentially threatened at the national level, due to the overexploitation and trade - see http://www.traffic.org/ecuador/executivesummary.html.
Steam distilling of the resin from the tree can be carried out to produce an essential oil, and this has been sold into the aromatherapy & incense trade. It is seen as a blood red oil which has a low impact odour profile, with sweet and leathery and castoreum–like character, and with some suggestion of varnish-like notes. The dry-out is disappointing with no perceptible odour at 24 hours (Burfield 2005). Bellesia F et al. (1996) note that the headspace of the sap from the tree contains ethyl acetate, ethyl propionate, 2-methylbutenol, 2-methylbutenyl acetate, propyl acetate, 3-methybutenyl acetate, eucalyptol, 1-butyl acetate, 3-methyl-2-pentanol – all relatively volatile and non-substantive items. Another report on www.rain-tree.com/sangre.htm notes the presence of pinenes, camphene, and the more substantive materials eugenol, linalol, vanillin and resin in the sap.
Pieters et al. (1993) investigated the healing activity of Dragons blood citing that proanthocyanins were involved in stimulation wound contraction, precipitating proteins which form a crust on the wound but which delay repair by decreasing fibroblast formation. Investigations by into the chemical composition of S. American Dragons Blood products form C. lecheri was carried out by Cai et al. (1991, 1993, 1993a) who found proanthocyanins (90%), catechins, epicatechins, gallocatechins, as well as clerodane diterpenoids amongst others in the sap.
Barry, Hedley, Drummond & Morrell (1926) Natural and Synthetic Resins p83-89.
Bellesia F. et al. (1996) “Headspace analysis of Croton lecheri L. sap” J Essen Oil Res 8(4), 435-7.
Burfield T. (2005) from the forthcoming 2nd edn. of Natural Aromatic Materials – Odours & Origins [1st edn. pub. by AIA, Tampa (2000)].
Cai Y et. al. (1991) “”Biological and Chemical Investigations of Dragon’s Blood from Croton Species of South America” Part 1. Polyphenolic compounds from C. lecheri.” Phytochemistry 30(6), 2033-40. Abstract: The blood-red sap of Croton lechleri was found to contain proanthocyanidins as major constituents which accounted for up to 90% of the dried weight. In addition to (+)-catechin, (−)-epicatechin, (+)-gallocatechin, (−)-epigallocatechin and dimeric procyanidins B-1 and B-4, five novel dimers and trimers were isolated and characterized as catechin-(4→8)- epigallocatechin, gallocatechin-(4→8)-epicatechin, gallocatechin-(4→6)-epigallocatechin, catechin-(4→8)- gallocatechin-(4→8)-gallocatechin and gallocatechin-(4→8)-gallocatechin-(4→8)-epigallocatechin. Higher oligomers were also obtained. A new procedure combining chemical degradation with 1H NMR spectroscopy has been developed for determination of the composition and molecular size of oligomeric/polymeric proanthocyanidins. The oligomers of the sap were shown to have the mean degree of polymerization of 4,5–6 and 6–7, respectively, and Mr up to 2130. The heterogeneity of the oligomers was clearly indicated by the presence of a variety of flavan-3-ols as extension and terminal units. An exceptionally high content of gallocatechin and epigallocatechin in the oligomers was observed.
Cai Y et. al. (1993) “”Biological and Chemical Investigations of Dragon’s Blood from Croton Species of South America” Part 2. Diterpenes from Croton lecheri.” Phytochemistry 32(3), 755-760.
Somewhat ironically, the day after writing this article, The Guardian Travel Supplement presented a major feature entitled "Exploring Socotra" (Guardian 2005). Charles Aithie reported on the widespread occurrence of the Dragon Tree in evergreen woodlands in the centre of the island. There was no mention of the threat to 300 unique species on the island from eco-tourism, the only major change on the island in 700 years, but Aithie instead relates his adventures in a group of eight travelling everywhere in 4 x 4 landcruisers - so I think we get the picture. Nick Baker penned a second article for the feature describing Socotra as on of the top 10 island sites where as far as biological diversity and endism is concerned (so why ruin it with eco-tourism?). Baker confirms that 30% of the plant species on the island occur nowhere else on the planet, and lists the uses of the sap from the Dragon tree as being as lipstick, and as a rust treatment on Socotra's cars - perhaps two of the most spurious uses yet to be described for these amazing trees.
Aithie C. "The Galapagos of Arabia"; & Baker N. (untitled) in "The Land that Darwin Forgot - Exploring Socotra" The Guardian 09.07.05 (Travel Supplement pp1-3).
Cai Y et. al. (1993a) “”Biological and Chemical Investigations of Dragon’s Blood from Croton Species of South America” Part 3. Clerodane diterpenoids from Croton lecheri.” Phytochemistry 34(1), 265-268.
Dietrich K. (1920) Analysis of Resins p.201 through Barry et al. (1926) Natural and Synthetic Resins p83-89.
Dobbie J.J. & Henderson G.G. (1884) “Red Resins Known as Dragons Blood”
Am. J. of Pharm. 86, 1884.
Edwards H.G., de Oliveira L.F., & Quye A. (2001). “Raman spectroscopy of coloured resins used in antiquity: dragon's blood and related substances.” Spectrochimia Acta Part A: Molecular & Biomolecular Spectroscopy 57(14) 2831-2842.
Edwards H.G., de Oliveira L.F., & Prendergast H.D. (2004) “Raman spectroscopic analysis of dragon's blood resins-basis for distinguishing between Dracaena (Convallariaceae), Daemonorops (Palmae) and Croton (Euphorbiaceae).” Analyst 129(2), 134-138.
Gonzalez A.G. et al. (2000) “Phenolic compounds of Dragon's blood from Dracaena draco.” J. Nat. Prod. 63(9), 1297-9.
Abstract: Three new compounds, 2,4,4'-trihydroxydihydrochalcone (1), 3-(4-hydroxybenzyl)-5,7-dimethoxychroman (2), and 7-hydroxy-3-(4-hydroxybenzyl)chromone (3), were isolated from the resin "Dragon's blood" obtained from Dracaena draco along with 18 known compounds. The structures of 1, 2, and 3 were determined using MS and NMR techniques
Hsu, Hong-yen et al. (1986) Oriental Materia Medica: a Concise Guide pub. Oriental Healing Arts Instit. of the United States.
Itokawa H. et al. (1991) “A Cytotoxic Substance from Sangre de Grado.” Chem. Pharm. Bull (Tokyo) 39(4), 1041-2.
Mabberley D.J. (1998) The Plant Book Cambridge Univ. Press (rev. edn 1998).
Pearson J. & Prendergast D.V. (2001) “Collectors Corner: Daemondrops, Dracaena and other Dragons Blood” Econ Bot. 55(4) 474-7.
Pieters L., Bruyne T de., Poel B. van, Vingerhoets R., Totté, J., Berghe V., V. Vanden., Vleitinck A. (1993) “In vivo wound healing activity of Dragon’s Blood (Croton spp.), a traditional South American drug, and its constituents” Phytomedicine 2(1), 17-22.
Piozzi F., Passsannanti S. & Paternostro MP (1974) “Diterpenoiod resin acids of Daemonorops draco” Phytochemistry 13, 2331-2233.
Rhozon E. et al. (1998) WO: 9816111 April 23, 1998.
Trease G.E. & Evans W.E. (1978) Pharmocognosy 11th edition Bailliere Tindall, London.
Wang J. et al. (1999) “Phytoalexins in Dracaena cochinchinensis resin. Chinese Journal of Applied Ecology 10, 255-6.
Zheng Qing-An, Chen Jiang-Tao, Zhang Ying-Jun, Yang Chong-Ren (2004) “Origin and Diffusion of Dragons Blood, a Famous Folk Herb” – see info.kib.ac.cn/kibinfoEN/soft/2941.htm
Milburn M. (1984). “Dragon’s Blood in East & West Africa, Arabia and the Canary Islands.” Africa 39(3), 486-493.