The genus Datura L. (Solanaceae) in Mexico and Spain – Ethnobotanical perspective at the interface of medical and illicit uses
Guillermo Benítez, Martí March-Salas, Alberto Villa-Kamel, Ulises Cháves-Jiménez,
Javier Hernández, Nuria Montes-Osuna, Joaquín Moreno-Chocano, Paloma Cariñanos
Journal of Ethnopharmacology, 2018, Volume 219, Pages 133-151.
A B S T R A C T
Ethnopharmacological relevance : The different species of the genus Datura have been used traditionally by some pre-Columbian civilizations, as well as in medieval rituals linked to magic and witchcraft in both Mexico and Europe. It is also noteworthy the use of different alkaloids obtained from the plants for medicinal purposes in the treatment of various groups of diseases, especially of the respiratory and muscularskeletal systems.
Aim of the study: A review of the ethnobotanical uses of the genus Datura in Mexico and Spain has been conducted. We focus on the medicinal and ritualistic uses included in modern ethnobotanical studies, emphasizing the historical knowledge from post-colonial American Codices and medieval European texts. Datura’s current social emergency as a drug of recreation and leisure, as well as its link to crimes of sexual abuse is also considered. The work is completed with some notes about the distribution and ecology of the different species and a phytochemical and pharmacological review of Datura alkaloids, necessary to understand their arrival in Europe and the ethnobotanical uses made since then
Materials and methods : A literature review and compilation of information on traditional medicinal uses of the genus has been carried out from the main electronic databases. Traditional volumes (codices) have also been consulted in libraries of different institutions. Consultations have been made with the National Toxicological Services of Spain and Mexico for toxicological data.
Results : A total of 118 traditional uses were collected in both territories, 111 medicinal ones to be applied in 76 conditions or symptoms included in 13 pathological groups. Although there are particular medicinal uses in the two countries, we found up to 15 similar uses, of which 80% were previously mentioned in post-Colonial American codices. Applications in the treatment of asthma and rheumatism are also highlighted. Apart from medicinal uses, it is worth noting their cultural and social uses, in the case of Mexico relating to diseases such as being scared, astonishment or falling in love, and in the case of Spain, as a recreational drug and lately, for criminal purposes.
Conclusions : This review highlights the variety of uses traditionally given to the different species in both territories. The fact that most of the coincident or similar uses in both countries also appear in the classical codices can be found an example of the flow, not only of the plants from America to Europe, but also of their associated information. It is also relevant that particular uses have derived in both countries, reflecting the difference in the cultural factors and traditions linked to rituals and cultural practices. Finally, the significant growth of Datura consumption in recent years as a drug of leisure and recreation, as well as in crimes of sexual submission, should be considered as research of maximum relevance in the field of forensic botany and toxicology.
Keywords : Ethnobotany, Cross-cultural study, Historical study, Scopolamine, Hyoscine
The Solanaceae family taxonomic classification has varied depending on which genera are included (about 90 in D’Arcy, 1979) and the subfamilies and tribes divisions (Wettstein, 1895; Bentham, 1876;
Baehni, 1946; D’Arcy, 1975).
In recent years the genus Datura L. has been considered, with Brugmansia Pers. and Iochroma Benth., to form the Datureae Tribe of the Solanaceae family (Olmstead et al., 2008; Mace et al., 1999).
So the genus consists of 14 species and several hybrids, distributed in three sections: Dutra Section (D. discolor Bernh., D. innoxia Mill. (see TROPICOS, 2017 for the nomenclature conflict with the illegitimated D. inoxia Mill.), D. kymatocarpa A.S. Barclay, D. lanosa Barclay ex Bye, D.metel L., D. pruinosa Greenm., D. reburra A.S. Barclay, D. wrightii Regel, all native to Mexico, D. leichhardtii F. Muell. ex Benth. endemic to Australia and D. velutinosa V.R. Fuentes, endemic to Cuba); Datura Section, with three species (D. ferox L., D. quercifolia Kunth and D. stramonium L.) and the Ceratocaulis Section with only the species D. ceratocaula Ortega (Avery, 1959, Luna-Cavazos et al., 2009). However, recent studies on molecular phylogeny reconsider this taxonomy and identify two subgroups in the Datureae subtribe: one with two species of Brugmansia Pers., and the other with 13 species of Datura (Bye y Sosa, 2013). The genus Datura is, in turn, composed of two groups: the first with section Ceratocaulis with only the species D. ceratocaula; and the second comprising a conglomerate of the other species distributed into two sections: the section Datura: D. arenicola Gentry ex Bye & Luna- Cavazos, D. discolor, D. ferox, D. kymatocarpa, D. leichhardtii. D. quercifolia and D. stramonium, and the polyphyletic section Dutra, with D. innoxia, D. lanosa, D. metel, D. reburra and D. wrightii (Bye and Sosa, 2013). In this way, the three classical sections are validated, but the species they include vary between the Datura and Dutra sections. In addition, D. pruinosa (accepting D. leichhardtii subsp. pruinosa (Greenm.) A.S. Barclay ex K. Hammer) and D. velutinosa (synonymous of D. innoxia) taxa are reorganized. On the other hand, the consistency of the newly validated taxon Datura arenicola Gentry ex Bye & Luna- Cavazos (the accepted name of the taxon, not the invalidated D. arenicola Gentry ex D.R.A. Watson, Watson, 2013, cf. TROPICOS, 2017) is recognized at molecular level. It is this taxonomic treatment (Bye and Sosa, 2013) that is followed in this article.
The origin and naturalness of Datura species is also currently controversial. Some studies have mentioned the presence of Datura in Asia and Europe in the pre-Columbian periods (particularly D. metel; Rätsch, 1998, Geeta and Gharaibeh, 2007, Rivera and Obón, 1991, but also D. ferox, Haegi, 1976). Based on classical Arabic (9th to 14th centuries CE) and Indian (3rd C BCE to 4th C CE) texts and on the analysis of some sculptures from India, Geeta and Gharaibeh (2007) concluded that some Datura species originated in the Old World. The presence of these plants (particularly D. metel and D. stramonium) in the Old World in ancient times has even been pointed out as an evidence for transoceanic contacts between America and the Old World before Columbus (Soreson, 2005). Significantly perhaps the genus name Datura has a Sanskrit origin from the word dhattūra (or dhatura) found in several classical texts (applied for D. metel; Rätsch, 1998, Geeta and Gharaibeh, 2007; Gallego, 2012). Nevertheless, this name was first used by Linnaeus (1737a) to replace the genus name Stramonium, previously used by Tournefort (1694), and was explained in the Hortus Cliffortianus (Linnaeus, 1737b) “as the future participle of the verb to give” (Gallego, 2012), in which an Indian origin is also stated (“crescit in india Occidentali; at naturalisata nunc ubbique per Europam” Sic!). However, studies on molecular phylogeny of the species have confirmed their American origin. Mexico and the south-west United States were established as the main center of origin and evolution of the genus, and therefore, the center of diversity (e.g. Symon and Haegi, 1991, Daunay et al., 2007, Dupin, 2013), including D. metel (Luna-Cavazos et al., 2009). Accepting this phylogenetic theory, many authors claim that some of the species, such as D. stramonium, D. metel and D. innoxia, were transported to Asia and Europe after post-European contact (f.i., Gallego, 2012; Symon and Haegi, 1991; Flora of China, 2017). For this reason, species from the Datura genus are considered today as cosmopolitan and naturalized in many regions with tropical and temperate climate conditions.
At the botanical level, the genus is formed of annual herbs and perennial shrubs, generally unarmed (with the exception of the fruit), and pubescent or glabrescent. The stems are erect and branched, with terminal branches welded to the petiole of the leaf. Basal leaves are usually simple or scattered, while those of the terminal branches are usually opposite or subopposed, petiolate. The actinomorphic flowers, hermaphrodite, without bracts and short-pediccellated, form an inflorescence reduced to a single flower, axillary. The corolla may be tubular or infundibuliform, white or more or less stained with violet, with longitudinal folds and acuminate lobes. The androceus, inserted in the tube of the corolla, can have all 5 stamens of equal length or 2 (3) slightly longer. Some species, such as Datura stramonium, produce flowers with a variation in the anther-stigme distance that has been shown to influence the outcrossing ratio, which may affect the number of fruits, seeds per fruit and seeds per plants (Bello-Bedoy and Núñez-Farfán, 2010). The ovary is covered with lanceolate or triangular-lanceolate epidermal extensions that become spinescent in fructification (aculeolate). The fruit is a bilocular capsule, or rarely tetralocular, dehiscent, containing reniform seeds, foveolate (Gallego, 2012).
From an ecological perspective, the genus Datura typically grows in nitrogen-rich soils and disturbed habitats, although one species, Datura ceratocaula, is semiaquatic (Kariñho-Betancourt et al., 2014). As a colonizer of open sites, the species can mainly be found in unstable habitats in areas perturbed by human activity, such as near roads, constructions, dwellings and domestic animal corrals (Bye et al., 1991). The distribution of species is relatively well known, particularly the distribution of Central American and South American species (see distribution maps for species of the Dutra section in Luna-Cavazos et al., 2009). Since most species of Datura are native to Mexico, they are well adapted to xeric conditions. In Mexico, the Balsas River Basin is one of the biogeographic regions with the highest species richness in the world, and it is considered to be the center of diversity for the Datura genus (Bye and Sosa, 2013).
All Datura species contain tropane alkaloids: organic nitrogenated bicyclic compounds which derive from the secondary metabolism of some plants. This group of alkaloids is shared with other genera of the Solanaceae family such as Brugmansia, Atropa, Mandragora, Physallis, Withania, etc. (Bruneton, 2001a). In addition to in Solanaceae, they are also present in some genera of families such as Erythroxylaceae, Brassicaceae, Convolvulaceae, Olacaceae, Proteaceae and Rhizophoraceae (Grynkiewicz and Gadzikowska, 2008; Dräger, 2004; Griffin and Lin, 2000; Bruneton, 2001a; Evans, 2008). Hyoscyamine and hyoscine (also known as scopolamine) stand out among the major tropane alkaloids of the genus (Berkov et al., 2006; Dugan et al., 1989; Friedman, 2004). The alkaloid content of the genus is the reason why the different species have had and still continue to have an important medicinal use in some countries (Grynkiewicz and Gadzikowska, 2008; Gaire, 2008; Gaire and Subedi, 2013; Figueroa-Morales, 2008). Species of Datura are used in many ways: as an antiparkinsonian (Poewe and Granata, 1997), antiepileptic (Peredery and Persinger, 2004), antispasmodic (Prabhakar and Nanda Kumar, 2006), antitussive (Dafni and Yaniv, 1994), medicine against facial neuralgia, head and ear pain (Ortíz de Montellano, 1980; Gorsi and Shanzad, 2002; Hussain et al., 2006; Ayyanar and Ignacimuthu, 2011), antiasthmatic (Pretorius and Marx, 2006), antirheumatic (Miraldi et al., 2001a), antimicrobial (Eftekhar et al., 2005), antifungal (Mdee et al., 2009) anti-inflammatory (Sonika et al., 2010), anthelmintic (Rajbhandari, 2001), and as an antidote in cases of cholinesterase poisoning (Bye et al., 1991). In addition, some in vitro studies point to the antibacterial activity of extracts of D. innoxia and D. stramonium against some Gram + bacteria (Eftekhar et al., 2005), Klebsiella pneumoniae and Staphylococcus aureus (Shagal et al., 2012), and some strains of Vibrio cholera and V. parahaemolyticus (Sharma et al., 2009). The anticancer effects of D. metel against human epidermal carcinoma have also been reported (Balachandran and Rajgopal, 2005), whereas the withanolides present in the seeds of Datura metel have been shown to have antiproliferative activity against human gastric adenocarcinoma
and potential immunosuppressive effects (Yang et al., 2014). Datura lanosa extracts have cytotoxic activity in carcinomas of colon, breast and lung (Gutiérrez-Lugo et al., 1996).
In Europe, the strength and anticholinergic properties of tropane and its pharmaceutical derivatives have led to the use of atropine sulfate in injectable solutions (European Pharmacopoeia, 2016). These solutions have been used in many remedies: in promoting auriculoventricular or atrioventricular block, in preventing and treating myocardial infarction, in pre-anesthesia for the symptomatic treatment of acute pain and functional disorders of the digestive and biliary tracts, as an antidote to acute anticholinesterase poisonings, as parasympathomimetic drugs, and for treatment of Parkinson (Giugni and Rodriguez-Cruz, 2016). In addition, atropine sulfate eye drops are used for treating inflammation of the uvea and to promote cyclopegia in cases of accommodative strabismus. Furthermore, scopolamine hydrobromide has been used to treat Parkinson’s and painful spasms. However, it is most commonly used to prevent motion sickness. It is not the aim of this synthesis to detail these activities or to specify the contraindications. For this information, the reader should seek out specialized literature (European Pharmacopoeia, 2016; U.S. Pharm. http://www. usp.org/).
Nevertheless, the possible side effects of the plants and plant extracts are well known (Jäger, 2015; Evans, 2008). The presence of alkaloids is also responsible for the use of these plants in rituals of shamanism and witchcraft in many places around the world (Carod-Artal, 2015; Gaire and Subedi, 2013). At the same time, their use has also led to some tragic events (Ertekin et al., 2005; Jiménez-Mejías et al., 1991; Oberdorfer et al., 2002). A small difference between doses of tolerance and highly toxic doses has been the cause of overdose poisoning (Arnett, 1995). This has led to fatal consequences, sometimes by accidental consumption (Gaire and Subedi, 2013), and in other cases by consumption as a recreational drug (Iglesias-Lepine et al., 2012).
The above information highlights the medicinal potential and importance of different Datura species, their particular phytochemistry and powerful biological activity on organisms. In part, the medicinal applications come from the traditional use of different species by the Mesoamerican pre-Columbian cultures, the center of origin for most of the species; while other new uses are the result of social habits and customs in Western cultures. In this work we make a historical review of the medicinal and ritualistic uses of the different species of Datura in Mexico and Spain, with emphasis on the traditional uses referenced in both the post-colonial Codices and the medieval European texts, as well as those included in modern ethnobotanical studies. Datura emergence as a drug for recreation and leisure use is a social emergency, and its link to crimes of sexual abuse is also considered. Our work finishes with some notes about the distribution and ecology of the different species and a phytochemical and pharmacological review of Datura alkaloids, necessary to understand their arrival in Europe and the ethnobotanical uses made since then.