Abstract
Context: Despite a rich tradition of folk medicinal usage of plants in the Peruvian Amazon, no studies documenting ethnobotanical information of Coronel Portillo Province of Ucayali Department have been published at an international level.
Objective: This field research documented traditional ethnobotanical knowledge related to the local use of medicinal plants.
Materials and methods: Ethnobotanical data were collected in native communities around Pucallpa city (Coronel Portillo Province of Ucayali Department, Peru) and in the city itself during the period June-October 2007. The data were collected through direct interviews with 23 people.
Results: Uses of 30 plant species belonging to 18 families in traditional medicine are described in this article. Botanical and vernacular names, plant part used, popular medicinal use, forms of preparation and applications of the herbal remedies for each species are reported.
Discussion and conclusion: Among investigated species, Brunfelsia grandiflora D. Don (Solanaceae), Calycophyllum spruceanum (Benth.) K. Schum. (Rubiaceae), Naucleopsis glabra Spruce (Moraceae), Phthirusa pyrifolia Eichler (Loranthaceae) were identified to be widely used in the studied area. However their beneficial health properties have not been well studied.
Introduction
It has been estimated that the flora of Peru represents 10% of the global plant diversity (CitationDe-la-Cruz et al., 2007), and about 20,000 species or 8% of the total number of plants that exist in the world can be found in the Peruvian Amazon (CitationDesmarchelier & Schaus, 2000). The richness of this diversity is reflected also in its use; for most people in Peru, it constitutes the prime resource for food, medicine, energy, craft, dye, fiber, art, ritual, and symbolic human activities (CitationDe-la-Cruz et al., 2007). Several ethnic groups that have lived in the Peruvian Amazon for centuries, such as the Shipibo-Konibo, Ashaninka, Cashibo-Cacataibo, Amuesha, Matsiguenka, have developed a deep knowledge of the ecosystems they inhabit (CitationCollado-Panduro et al., 2004; CitationSalick, 1989; CitationWezel & Ohl, 2005). The large number of Amazonian ethnics have practiced consistent application of different plant species for various ailments for millennia, and have transmitted this long-term experience from one generation to the next (CitationDesmarchelier & Schaus, 2000). Among them, the people of the Shipibo-Konibo tribe also developed their own conceptions of wellness and illness and built up ethnomedical systems including therapies based on medicinal plants (CitationFoller, 1995; CitationLenaerts, 2006). Nonetheless, indigenous peoples are not the only ones who have a detailed knowledge of the local Amazonian ecosystems in which they live. The long-term residents of Amazonia (e.g., mestizos) do as well (CitationDufour, 1990). Many Amazonian mestizo communities are dependent on traditional medicine as their only source of health care, because of its tradition and lower price than the cost of western therapy. Also, mobility is not unusual among Amazonian mestizos and internal migration has enriched traditional knowledge in their communities, thereby Amazonian mestizos have a large repository of traditional knowledge which may have been adopted from extinct or endangered indigenous cultures (CitationJovel et al., 1996).
Despite a rich tradition of folk medicinal usage of plants in Peruvian Amazon and certain ethnobotanical studies published (CitationLuna, 1984; CitationPhillips & Gentry, 1993a, Citation1993b; CitationJovel et al., 1996), no studies documenting ethnobotanical information of Coronel Portillo Province of Ucayali Department have been published at an international level. Therefore, the purpose of this paper is to document indigenous information on traditional use of medicinal plants and thus help to conserve the rapidly disappearing ethnobotanical knowledge in Coronel Portillo Province of Ucayali Department in Peru.
Methods
Study area
The study was performed in communities of Amerindians of the tribe Shipibo-Konibo (Yarinacocha, San Francisco, Santa Rosa de Dinamarca and Santa Teresita) around Pucallpa city in the Amazon basin of Peru and with mestizos living in the city itself. Pucallpa is administrative center of Coronel Portillo Province and the capital of Ucayali Department (). The city lying on the banks of the river Ucayali is located 860 km from Lima with an altitude of 154 m above sea level, 8°23′ S, and 74°31′ W. Ucayali Department borders Brazil to the east, along an east-west gradient leading to the foothills of the Andes. The area of Ucayali Department is 102,410 sq km (13% of the Amazon basin) and is divided into four provinces: Coronel Portillo, Padre Abad, Atalaya and Purus (CitationPimentel et al., 2004). Pucallpa is characterized by humid tropical forest cover and by a hot and humid climate that varies only imperceptibly throughout the year. The rainfall ranges from 1800 to 3000 mm per year, and the rainy season is from February to May and from September to December (CitationFujisaka et al., 2000). The mean annual temperature is 25.7°C, and average annual relative humidity reaches 80% (CitationLojka et al., 2008).
Figure 1. Location of the Coronel Portillo Province and Ucayali Department in Peru.
According to the last published national population census in 1993, the Ucayali Department has 331,824 inhabitants; the largest indigenous ethno-linguistic group living in this region is the Shipibo-Konibo group (). The traditional agriculture is the primary livelihood of the village people, for food, fodder, fuels, and medicaments (CitationPimentel et al., 2004). The Shipibo’s traditional subsistence system was based on swidden agriculture, fishing, hunting and then gradually shifted to agriculture, perhaps when hunting and gathering brought in insufficient food to support them (CitationFoller, 1995).
Figure 2. Distribution of Shipibo-Konibo ethnic group in Ucayali Department, Peru (adapted from CitationPimentel et al., 2004).
Data collection
In four communities studied, all shamans were contacted and then interviews were performed; all herbalist and healers in Pucallpa markets were contacted, but not all of them were willing to cooperate. Consequently, the information was only obtained from persons who acquiesce in cooperation. Each participating respondent was acknowledged with a package of “mapachos” (cigarettes used for smoking by shamans during healing rituals). The study was undertaken with the participation of 23 individuals (12 women, 11 men) whose ages ranged from 22 to 78 years in the period June-October 2007. The respondents belonged to two main ethnic groups, 10 were Amerindians of the tribe Shipibo-Konibo and 13 were mestizo people. Since all of the interviewees spoke Spanish or both Spanish and Shipibo-Konibo language, the interviews were conducted in Spanish, to enable them to give accurate information with ease.
The data were collected through a survey employing individual semi-structured interviews (CitationAlexiades & Sheldon, 1996) and a guided open-ended questionnaire (CitationMartin, 2004), using a pre-selected set of reference specimens (CitationMartin, 2004) and free-listing previously used by CitationQuave and Pieroni (2007) and CitationQuinlan (2005). Each questionnaire documented personal data on informants (name, gender, age, ethnicity, linguistic group, occupancy, community of his/her origin, and current settlement) and the ethnobotanical information.
With a view to gathering data especially on prospective species for future biological activity assessment, we have created a pre-selected set of reference specimens (CitationMartin, 2004) based on locally used medicinal plants for which there is a general lack of modern pharmacological studies [e.g., Calycophyllum spruceanum (Benth.) K. Schum. (Rubiaceae), Dracontium loretense K. Krause (Araceae), Naucleopsis glabra Spruce (Moraceae) and Phthirusa pyrifolia Eichler (Loranthaceae)]. The preliminary selection of species was based on local available literature focused on medicinal plants used in Ucayali Region (CitationClavo et al., 2003) or by the Shipibo-Konibo ethnic group (CitationArevalo, 1994), as well as on ethnobotanical (CitationDuke & Martinez, 1994) or ethnopharmacological literature focused on the Amazon Basin (CitationDesmarchelier & Schaus, 2000). The list of selected species was finalized based on consultations with Anders Hansson and Mirella Clavo, both long-time experienced experts on ethnobotany and ethnopharmacology of medicinal plants traditionally used in the Ucayali Department.
Information on vernacular names, plant part used, popular medicinal use, forms of preparation and applications of the herbal remedies on each selected species was requested. At the end of the questionnaire the interviewees had time for free-listing of species (CitationQuave & Pieroni, 2007) which have medicinal importance for them and were not included in the list. The enquiry on preparation of medicaments was completed by observation of participants (CitationMartin, 2004). The information was immediately registered in field notebooks. The interview prompts were requested, e.g., local counterparts were asked to show the plant species on site. Photographs and voucher specimens of studied plants were prepared according to CitationAlexiades and Sheldon (1996) to document the identity of plant material. All plant material was collected by L. Polesna and subsequently authenticated in cooperation with M. Clavo. Voucher specimens are deposited at the herbarium of the National University of Ucayali in Pucallpa, Peru. CitationThe International Plant Names Index (2008) database was used to determine the correct scientific names of studied plant species. The translation of folk names of illnesses to English was consulted with A. Hansson.
Results
The uses of 30 medicinal plants belonging to 18 families are reported in , in which the plant species are listed in alphabetical order. For each species, the following ethnobotanical and pharmacognostic elements are provided: botanical name, local names, parts used, preparations, ailments treated, total number of reports, and relevant percentage of citations. The most represented families are Euphorbiaceae (4 species), Fabaceae (4), Solanaceae (4), and Rubiaceae (3). These four families together represent 50% of total number of medicinal plants studied. The remaining 50% of species belong to 14 families, each represented by one or two species. According to the number of citations (20 and more) reporting species used in folk medicine Brunfelsia grandiflora D. Don (Solanaceae), C. spruceanum, Croton lechleri Müll. Arg. (Euphorbiaceae), Euterpe precatoria Mart. (Arecaceae), Jatropha gossypiifolia L. (Euphorbiaceae), Maytenus macrocarpa Briq. (Celastraceae), N. glabra, P. pyrifolia, Phyllanthus niruri L. (Euphorbiaceae), Uncaria guianensis J.F.Gmel. (Rubiaceae), and U. tomentosa D.C. (Rubiaceae) were identified as the most popularly used plants in Coronel Portillo Province of Ucayali Department by both shamans of Shipibo-Konibo communities and herbalists on the markets. Interestingly, although Equisetum giganteum L. (Equisetaceae) and Caesalpinia spinosa (Molina) Kuntze (Caesalpiniaceae) were observed to be popularly sold by mestizos herbalists on Pucallpa markets and almost all respondents were able to describe indications of these species, there is no cultural tradition in Shipibo-Konibo communities in medicinal treatment by either of these species. The highest number of studied plants (44%) used for medicinal properties of total species are trees, followed by shrubs and herbs represented by 23% and 17%, respectively. Three climbers, one epiphyte and one palm were also identified among investigated species.
Table 1. Medicinal plants used in Coronel Portillo Province of Ucayali Department.
The whole aerial part, bark, entire plant, fruits, latex, leaves, mixtures (bark with leaves, bark with leaves and fruits or flowers with leaves), resin, roots, sap, seeds, trunk, and tuber were found to be plant parts used for medicinal properties, whereas the bark of the trunk was the most frequently utilized material (36%), followed by the entire plant (14%). Standard methods of preparation of remedies were observed to be decoction (plant material boiled in water), tincture (plant material soaked in alcohol), infusion (extract in hot water), macerate (extract in cold water), fresh material or cataplasm.
A total of 108 ailments were reported to be treated by the studied plant species, of which 53% were recommended for rheumatism, 50% were described as healing agents for wounds, and 39% are used for kidney disorders. Arthritis, diabetes, prostate problems and stomach ache are cured by 11 species (35%) each. Kidney disorder was the most often cited health problem by informants (87), followed by wounds (52). The decoction prepared from roots of E. precatoria was recommended for kidney disorders by 18 respondents (78%), M. macrocarpa and P. niruri by 16 (70%) each, and E. giganteum by 15 (65%). C. lechleri was indicated for wound healing with the highest number of citations (>60%). Eighteen respondents (78%) described cataplasm from P. pyrifolia for treatments of fractures. Though all respondents described identical indications for both studied Uncaria species, U. tomentosa is markedly more used in Coronel Portillo Province. From all ailments described, 19 (18%) were mentioned only once. All of the studied species were described to have multiple uses.
The ethnomedicinal indications were mentioned by more than half of the total number of respondents for 79% of plant species pre-selected by the authors [B. grandiflora, C. spinosa, C. spruceanum, D. micrantha Harms (Fabaceae), Dipteryx loretense, E. giganteum, Erythrina edulis Triana (Fabaceae), M. macrocarpa, N. glabra, P. pyrifolia, P. niruri, Piper aduncum Vell. (Piperaceae), Solanum mammosum L. (Solanaceae), U. guianensis and U. tomentosa)]. Although for all pre-selected species some ethnopharmacological data were recorded, some plants selected by their medicinal properties and abundance in studied region are used as remedies less frequently [Pterocarpus rohrii Vahl. (Fabaceae), Solanum sessiliflorum Dunal (Solanaceae), Tabebuia chrysantha G. Nicholson (Bignoniaceae) and Terminalia catappa L. (Combretaceae)]. The medicinal properties of T. catappa were mentioned by the fewest number of local counterparts.
Discussion
During our survey we identified several plant species whose local medicinal use against specific health disorders have not been previously verified by modern ethnopharmacological methods. Among them, B. grandiflora has been subjected to several phytochemical (CitationLloyd et al., 1985; CitationBrunner et al., 2000; CitationFuchino et al., 2008) and biological activity-related studies showing in vitro antibacterial (CitationKloucek et al., 2005) and leishmanicidal (CitationFuchino et al., 2008) effects of this species. However, despite extensive use of tincture prepared from its root as a popular remedy for rheumatism and arthritis recorded during our study, which is moreover in correspondence with ethnopharmacological indications previously summarized by CitationDesmarchelier and Schaus (2000), we did not find any modern pharmacological reports dealing with evaluation of anti-inflammatory activity of B. grandiflora. Similarly, with the exception of papers on antimicrobial (CitationKloucek et al., 2007) and antioxidant (CitationSvobodova et al., 2007) activities of N. glabra, the species for which the frequent use of bark tincture against arthritis and rheumatism was recorded in this study, there are no reports confirming experimentally the anti-inflammatory properties of this plant. In correspondence with previously described traditional uses of C. spruceanum for treatment of influenza, mycoses, and other diverse infections in various regions of Amazonia (CitationZuleta et al., 2003) we observed frequent use of this species against acne, cough, diarrhea, ulcers, and vaginal infections indicating the anti-infective properties of this plant. However, despite solitary reports on in vitro antioxidant activity of C. spruceanum stem bark extract (CitationSvobodova et al., 2007) and presence of iridoids (CitationZuleta et al., 2003) the pharmacology and phytochemistry of this species are poorly known; there are no available studies on its potential antimicrobial properties. Similarly, the tubers of D. loretense widely used by local healers against rheumatism, snakebites, abdominal pains or gastritis have only poorly been studied for their pharmacological properties (CitationDesmarchelier et al., 1997; CitationKloucek et al., 2005). In the case of P. pyrifolia, which in the region studied is commonly used for treatments of fractures and muscle injuries, modern studies focused on biological effects of the plant are almost completely lacking.
By comparing the data obtained on the ethnopharmacological use of plants in Coronel Portillo Province with those of inventories performed with other mestizo and Quechua communities (CitationJovel et al., 1996; CitationSanz-Biset et al., 2009), we find several species reported in our article, such as B. grandiflora, C. spruceanum, E. precatoria, Hura crepitans L. (Euphorbiaceae), M. macrocarpa, Physalis angulata L. (Solanaceae), Piper peltatum L. (Piperaceae), S. mammosum, S. sessiliflorum, U. tomentosa, and U. guianensis, to be also traditionally used in different geographical areas of the Peruvian Amazon; however, the methods of and reasons for their use varied in many recorded cases. For example, in contrast to mestizos from the Suni-Mirano community (CitationJovel et al., 1996), respondents from Coronel Portillo Province did not mention P. peltatum as a plant causing male impotency but they referred to the sap of this species as an agent for the treatment of conjunctivitis. Similarly, some species commonly sold in Pucallpa markets such as Anacardium occidentale L. (Anacardiaceae), C. spinosa, Cordia alliodora Cham. (Boraginaceae), C. lechleri, E. giganteum, J. gossypiifolia, P. niruri, P. aduncum, S. mammosum, and Uncaria tomentosa were recorded by CitationBussmann and Sharon (2006) at markets in Northern Peru, but their uses differed in some cases for each compared market place. Based on these facts, we suppose that popular medicinal uses of species mentioned above in several regions of Peruvian Amazon indicate their prospective pharmacological properties and suggest these plants as promising materials for detailed verification of their biological activities and chemical composition.
Conclusions
This report documents ethnobotanical data on 30 medicinal plants traditionally used by shamans of the Shipibo-Konibo tribe and mestizo healers in Coronel Portillo Province of Ucayali Department in Peru. Based on the results achieved, we can conclude that the frequency of traditional medicinal use in studied area recorded for several species described in this study, namely B. grandiflora, C. spruceanum, C. lechleri, E. precatoria, J. gossypiifolia, M. macrocarpa, N. glabra, P. pyrifolia, P. niruri, U. guianensis, and U. tomentosa supported by similarities of their popular medicinal uses in different regions of the Peruvian Amazon indicate their significant ethnopharmacological properties. Moreover, the lack of modern scientific data documenting health beneficial effects of several of the above-mentioned species such as B. grandiflora, C. spruceanum, N. glabra, or P. pyrifolia suggests these plants as promising materials for detailed evaluation of their chemical and pharmacological characteristics. In addition, we believe that the ethnobotanical information collected in this study may significantly contribute to biodiversity conservation and preservation of traditional knowledge on medicinal plants of the region studied.
Acknowledgments
The authors are very thankful to all informants for sharing their ethnobotanical knowledge.
Declaration of interest
This research was supported by the Czech Republic’s Development Cooperation project (23/MZe/B/07-10), the Youth Activity Fund of Explorers Club, the Foundation “Nadani Josefa, Marie a Zdenky Hlavkovych”, and the Czech University of Life Sciences Prague (CIGA 20085001).
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