Abstract
Traditional knowledge is an important source of obtaining new phytotherapeutic agents. Ethnobotanical survey of medicinal plants was conducted in Nossa Senhora Aparecida do Chumbo District (NSACD), located in Poconé, Mato Grosso, Brazil using semi-structured questionnaires and interviews. 376 species of medicinal plants belonging to 285 genera and 102 families were cited. Fabaceae (10.2%), Asteraceae (7.82%) and Lamaceae (4.89%) families are of greater importance. Species with the greater relative importance were Himatanthus obovatus (1.87), Hibiscus sabdariffa (1.87), Solidago microglossa (1.80), Strychnos pseudoquina (1.73) and Dorstenia brasiliensis, Scoparia dulcis L., and Luehea divaricata (1.50). The informant consensus factor (ICF) ranged from 0.13 to 0.78 encompassing 18 disease categories,of which 15 had ICF greater than 0.50, with a predominance of disease categories related to injuries, poisoning and certain other consequences of external causes (ICF = 0.78) having 65 species cited while 20 species were cited for mental and behavioral disorders (ICF = 0.77). The results show that knowledge about medicinal plants is evenly distributed among the population of NSACD. This population possesses medicinal plants for most disease categories, with the highest concordance for prenatal, mental/behavioral and respiratory problems.
1. Introduction
Despite the fact that modern medicine, on the basis of the complex pharmaceutical industry, is well developed in most part of the world, the World Health Organization (WHO) through it Traditional Medicine Program recommends its Member States to formulate and develop policies for the use of complementary and alternative medicine (CAM) in their national health care programmes [1]. Among the components of CAM, phytotherapy practiced by the greater percentage of the world population through the use of plants or their derivatives, occupies a significant and unique position [2].
In this sense, documentation of the indigenous knowledge through ethnobotanical studies is important in the conservation and utilization of biological resources [3].
Brazil is a country with floral megadiversity, possessing six ecological domains, namely, Amazonian forest, Caatinga, Pampas, Cerrado, Atlantic Forest, and the Pantanal [4]. Mato Grosso region is noteworthy in this regard, as it occupies a prominent position both in the national and international settings, for it presents three major Brazilian ecosystems (the Pantanal, Cerrado, and Amazonian rainforest). Besides this, it also hosts diverse traditional communities in its territories, namely, the Indians descents (Amerindians), African descents, and the white Europeans. However, due to the mass migration from the rural areas and technological development, coupled with globalization of knowledge by the dominant nations, cultural tradition concerning the use of medicinal plants is in the major phase of declining [5].
The Pantanal is distinguishably the largest wetland ecosystem of the world, according to the classification by UNESCO World Heritage Center (Biosphere Reserve) [4]. The Pantanal vegetation is a mosaic consisting of species of the Amazonian rainforest, Cerrado, Atlantic forest, and Bolivian Chaco, adapted to special conditions, where there is alternations of both high humidity and pronounced dryness during the time of the year [4]. The presence in the Pantanal of the traditional populations that use medicinal plants for basic health care makes this region an important field for the ethnobotanical and ethnopharmacological studies [6, 7].
Because of the fact that the Pantanal communities are relatively isolated, they have developed private lives that involved much reliance on profound knowledge of the biological cycles, utilization of natural resources, and traditional technology heritage [8].
As a result of the aforementioned, this study aimed to systematically and quantitatively evaluate the information gathered from these Pantanal communities, highlight the relevance of the ethnobotanical findings, and cite and discuss relevant literatures related to medicinal plants with greater relative importance (RI) and high informant consensus factor (ICF) values obtained in the study.
2. Materials and Methods
2.1. Study Area
For the choice of study area, literature search was conducted to identify the Pantanal region in Mato Grosso, consisting of traditional communities where such studies have not yet been conducted and/or there were no ethnobotanical survey publications. The study design was cross-sectional and was conducted between the period of November, 2009 and February, 2010. The study setting chosen was NSACD located in the Poconé municipality, Mato Grosso State, Central West of Brazil (Figure 1) with coordinates of 16° 02′ 90′′ S and 056° 43′ 49′′ W. Poconé is located within the region of Cuiabá River valley, with an altitude of 142 m, occupies a territorial area of 17,260.86 km2, and of tropical climate. The mean annual temperature is 24°C (4–42°C) and the mean annual rainfall is 1,500 mm with rainy season occurring between December and February. The municipality is composed of 2 Districts (NSAC and Cangas), 5 villages, 11 settlements, 14 streets, and 72 communities (countryside) [9]. The population of NSACD is estimated to be 3,652 inhabitants, representing 11.5% of Poconé municipality [10]. The principal economic activities are mainly livestock farming, mining, and agriculture with great tourism potentials, because Poconé municipality is the gateway to the Pantanal region [9].
2.2. Consent and Ethical Approval
Authorization and ethical clearance were sought from the relevant government (Health authority of Poconé and the National Council of Genetic Heritage of the Ministry of Environment (CGEN/MMA), Resolution 247 published in the Federal Official Gazette, in October, 2009, on access to the traditional knowledge for scientific research and Federal University of Mato Grosso and Júlio Muller Hospital Research Ethical Committees, Protocol 561/CEP-HUJM/08 authorities. Previsits were made to each community of NSACD to present the research project as well as to seek the consent of each potential informant.
2.3. Data Collection and Analysis
In this present study, sampling was done using probabilistic simple randomization and stratified sampling techniques [10, 11].
The population studied consists of inhabitants of 13 communities of NSACD, Mato Grosso State, considering an informant per family. The criteria for each informant chosen were age of 40 and above, residing in NSACD for more than 5 years (because there is large migration into the area because of the presence of ethanol producing factory).
These criteria are in line with the study objective coupled with the information gathered from the local authority [12].
In order to determine the estimated sample size (), in this case, the number of families to be sampled per communities being considered, the following formula was utilized [11, 13]:
This study considered the population size of 1,179 families (, 179), confidence coefficient of 95% (), sampling error of 0.05 (), a proportion of 0.5 (). It should be noted that the was assigned due to nonexistence of previous information about this value as is usual in practice, to obtain conservative sample size which is representative at the same time.
In determining the sample size for the microarea, 5% error and 10% loss in sample were considered. To determine the sample size in each microarea, the sample size (290) was multiplied by the sampling fraction of each microarea and dividing the total number of families of the same microarea with the total number of families of all the microareas (1,179), thereby arriving at the sample sizes for each area as shown in Table 1.
The interviews were conducted with the help of 12 trained applicators, under the supervision of the respective investigator. Data collected included sociodemographic details, vernacular names of the plant species with their medicinal uses, methods of drug preparation, and other relevant information. The ethnobotanical data were organized using the Microsoft Office Access 2003 program and statistically analyzed using SPSS, version 15 for Windows (SPSS Inc., Chicago, Illinois, USA).
2.4. Plant Collection, Identification, and Herborization
The collection of plant materials were done in collaboration with the local specialists, soon after the interviews. Both indigenous and scientific plant names were compiled. The plant materials collected during the study period were herborized, mounted as herbarium voucher specimens, and deposited for taxonomic identification and inclusion in the collection of Federal University of Mato Grosso and CGMS Herbarium of Federal University of Mato Grosso do Sul, Brazil.
Plant species were identified according to standard taxonomic methods, based on floral morphological characters, analytical keys, and using, where possible, samples for comparison, as well as consultations with experts and literature [6, 7, 14–19]. The plant species obtained were grouped into families according to the classification system of Cronquist [20], with the exception of the Pteridophyta and Gymnospermae. For corrections of scientific names and families, the official website of the Missouri Botanical Garden was consulted [21].
2.5. Quantitative Ethnobotany
The relative importance () of each plant species cited by the informants was calculated according to a previously proposed method [22]. In order to calculate , the maximum obtainable by a species is two was calculated using (2) according to Oliveira et al. [23] where RI: relative importance; NCS: number of body systems. It is given by the number of body systems, treated by a species (NSCS) over the total number of body system treated by the most versatile species (NSCSV): NCS = NSCS/NSCSV; NP: number of properties attributed to a specific species (NPS) over the total number of properties attributed to the most versatile species (NPSV): NP = NPS/NPSV.
We sought to identify the therapeutic indications which were more important in the interviews to determine the informant consensus factor (ICF), which indicates the homogenity of the information [23].
The ICF will be low (close to 0), if the plants are chosen randomly, or if the informants do not exchange information about their uses. The value will be high (close to 1), if there is a well defined criterion of selection in the community and/or if the information is exchanged among the informants [23].
ICF was calculated using the number of use citations in each category of plant disease (), minus the number of species used () divided by the number of use citations in each category minus one on the basis of (3):
The citations for therapeutic purposes were classified using the 20 categories of the International Classification of Diseases and Related Health Problems, 10th edition-CID [24]: injuries, certain infectious, and parasitic diseases (I); neoplasms-tumors (II), diseases of blood and blood-forming organs and certain disorders involving the immune mechanism (III), endocrine, nutritional and metabolic diseases (IV) mental and behavioral disorders (V), nervous system (VI), diseases of eye and adnexa (VII), diseases of the ear and mastoid process (VIII), diseases of the circulatory system (IX), respiratory diseases (X), digestive diseases (XI), diseases of the skin and subcutaneous tissue (XII), diseases of the musculoskeletal system and connective tissue (XIII), genitourinary diseases (XIV), pregnancy, childbirth and (XV), certain conditions originating during the perinatal period (XVI), symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (XVIII) and injury, poisoning and certain other consequences of external causes (XIX).
We selected for further discussion species that presented ≥ 1.5, and are in a category with high ICF. We conducted literature review using among others, the databases of Web of Science, MEDLINE, SciELO and including nonindexed works. We also searched national data bases for dissertations and theses.
3. Results
A total of 262 informants were interviewed, representing 7.17% of the population of NSACD, 22.22% of the population aged ≥40 years and residing in the District for over five years. Of the respondents, 69% were female and 31% male, aged 40–94 years (median 55). 68% were born in the city of Poconé, and 62% have been residents for over 20 years in the District (Table 2).
Of the 262 respondents, 259 (99.0%) reported the use of medicinal plants in self health care, with a minimum of 1 plant and a maximum of 250 plants among the female respondents and a minimum of 2 plants and a maximum of 54 among the male respondents. A total of 3,289 citations were recorded corresponding to 376 different plant species which belong to 285 genera and 102 families. Fabaceae (10.2%), Asteraceae (7.82%), and Lamaceae (4.89%) families were the most representative in this study (Table 3).
3.1. Relative Importance (RI)
The of the species cited by 262 respondents from NSACD ranged from 0.17 to 1.87. A total of 261 species had ≤ 0.5; 80 species, from 0.51 to 1.0; 30 species, from 1.1 to 1.5, and 4 species with from 1.51 to 2.0, among the latter, three species were native to Brazil. The species with ≥ 1.5, were Himatanthus obovatus (Müll. Arg.) Woodson (1.87), Hibiscus sabdariffa L. (1.87), Solidago microglossa DC. (1.80), Strychnos pseudoquina A. St.-Hil. (1.73), Dorstenia brasiliensis Lam., Scoparia dulcis L., and Luehea divaricata Mart. (1.50 each), as shown in Table 4.
3.2. Informant Consensus Factor (ICF)
In the disease categories according to CID, 10th ed., we observed that ICF values ranged from 0.43 to 0.77, with the exception of disease category included in CID VI (diseases of the nervous system), which was 0.13. The ICF for CID VI ranged between 0.13 and 0.78 (mean = 0.62, SD = 0.16, 95% CI: 0.53–0.70). The highest consensus value obtained was for the category related to injuries, poisoning, and some other consequences of external causes (ICF = 0.78), with 65 species and 286 citations. Three species were more common, namely, S. dulcis and S. microglossa (“Brazilian arnica”), with 49 citations each and L. pacari (manga-brava) with 42 citations. The main ailments addressed in this category were inflammation, pain, and gastric disorders.
Out of 20 disease categories, there were citations for 18 therapeutic indications, as shown in Table 5.
4. Discussion
In the present study, almost all the respondents (99%) claimed to know and use medicinal plants. Surveys conducted in other countries had reported values ranging from 42% to 98% depending on the region and country of the study [25–27]. Due to the low level of knowledge of traditional medicine in national capitals, ethnobotanical surveys in many developing countries including Brazil, primarily prefer to evaluate small communities or rural hometowns, whose population having knowledge and practical experience with traditional medicine are proportionately higher (between 80 and 100%) [28–30].
The high percentage of folk knowledge of medicinal plants identified in Brazil may be due to factors such as lower influence of the contemporary urban lifestyle and the strength of cultural traditions in the rural communities [31]. In fact, with the process of industrialization and migration to the cities, a significant part of traditional culture is maintained more in the communities farther from the metropolis via oral transmission of the knowledge of CAM and family traditions. Transmission and conservation of CAM knowledge is more pronounced in Brazil due to high degree of biodiversity.
One of the most important aspects of this research is the documentation of high number of taxa (285 genera and 102 families) and species (376) mentioned by the informants as medicinal. These findings confirmed the existence of the great diversity of plants used for therapeutic purpose and preserved traditional culture, as stated by Simbo [32]. It is worth mentioning here the presence of 8 (eight) local medicinal plant expert informants/healers among the 262 respondents in this study. These local expert informants/healers account for a significant number of citations (43 to 250) in this study. In Brazil, as in other countries, rural communities have developed knowledge about the medicinal and therapeutic properties of natural resources and have contributed to the maintenance and transmission of the ethnopharmacological knowledge within the communities.
The most representative plant families are Fabaceae (10.2%), Asteraceae (7.82%), and Lamiaceae (4.89%). These results are in accordance with other ethnobotanical surveys conducted in the tropical regions [33, 34] including Brazil [7, 35]. Furthermore, the results from our study are also in conformity with the findings of the most comprehensive ethnobotanical survey conducted by V. J. Pott and A. Pott in the Brazilian Pantanal region [19].
Featuring greater potential for bioprospecting are 231 (61.6%) species indicated for the treatment of at least two diseases, and RI between 0.17 and 1.87 (mean = 0.46, SD = 0.357, 95% CI: 0.4250–0.4973). The seven species with the highest were H. obovatus (Müll. Arg.) Woodson (13 therapeutic indications and = 1.87, H. sabdariffa L. (12 therapeutic indications and = 1.87); S. microglossa DC. (9 therapeutic indications and RI = 1.80) S. pseudoquina A. St. - Hil. (14 therapeutic indications and = 1.73) and D. brasiliensis Lam., S. dulcis L., and L. divaricata Mart. (12, 10, and 12 therapeutic indications respectively with = 1.50) (Table 4). For the sake of brevity, we will focus most of our discussion on these seven most cited medicinal plants highlighting the most important available literature on them and including L. pacari. It should be noted that although 146 (39%) species presented RI below 0.17, with just a single indication, they cannot be considered as of lower pharmacological potential or importance, because as Albuquerque et al. [36] have noted elsewhere, these may be species of recent introduction in the culture of the community under study but might have been validated by the customary use in other social groups.
A total of 105 different folkways, including 18 disease categories, according to Brasil [24], were codified as shown in Table 5. The highest frequencies in decreasing magnitude were indications for the treatment of pain and inflammation (10.8%), kidney disease (7.6%), and wound healing (6.8%). In part, these data can be explained by the characteristics of the informants (elderly, rural activity, low level of education, and poor sanitation at home) with higher frequency of chronic, inflammatory, and infectious diseases. In addition, the search for natural treatments for infected wounds is very common in populations of agrarian labor or menial worker as stated by Akerreta et al. [37]. As ICF values were generally close to 1.0, it may be presumed that there is certain homogeneity in knowledge of medicinal plants among the population of NSACD.
4.1. Literature Survey and Discussions on the Selected Species with Higher Relative Importance
Himatanthus obovatus, var. obovatus had the highest relative importance, being cited for 13 different ailments that fall into 11 categories of CID, 10th ed. with a total of 29 citations. The most commonly mentioned of these indications for this plant were its traditional use as a blood cleansing, wound healing, and other conditions associated with infections, which seems to point to its possible antibiotic activity. Indeed, some studies have demonstrated the in vitro activity of its different extracts against promastigotes of Leishmania donovani [38]. A few others also showed experimentally its antiviral, antitumor activities, cellular proliferation activities, and inflammatory and immune response [39, 40]. On the basis of these aforementioned, it is possible that its use in the folk medicine may be related to its ability to modulate the immune system, which may enhance physiological mechanisms involved in resolving inflammation, pain, and wound healing. We did not encounter any literature pertaining to its use in anemia, nosebleeding, muscle relaxant, deworming, or vitiligo treatment. Its indications as a blood cleansing and as antihypercholesterolemic are important targets for future biomedical research.
Hibiscus sabdariffa calyces are used in many parts of the world to make cold and hot drinks as well as in folk medicine [41]. Due to its many health-enhancing benefits, extensive works have been carried to validate its traditional therapeutic claims. In fact, its medicinal importance is widely acknowledged in many traditional herbal systems [42].
The benefits associated with the use of H. sabdariffa may in part be due to its high content of beneficial phytochemical constituents. These include alkaloids, L-ascorbic acid, anisaldehyde, anthocyanin, β-carotene, β-sitosterol, citric acid, cyanidin-3-rutinoside, delphinidin, galactose, gossypetin, hibiscetin, mucopolysaccharide, pectin, protocatechuic acid, polysaccharide, quercetin, stearic acid, and flavonoids [42, 43]. Studies have highlighted the role of polyphenol acids, flavonoids, and anthocyanins that may act as antioxidants or through other mechanisms that may contribute to its cardioprotective activity [44, 45].
In additions to folkloric use of H. sabdariffa noted in this study, other previous reports have indicated its use in the treatment of liver disease, hypocholesterolemic, antispasmodic, intestinal antiseptic, sedative, and as mild laxative [42, 46]. The most extensively studied is its antihypertensive activity. This effect was confirmed in several in vitro and animal studies [47–49]. The hypotensive effect of H. sabdariffa and its constituents may be mediated, at least partially, by a cholinergic and/or histaminergic mechanism and it has been confirmed to act via inhibitiory action on angiotensin I converting enzyme, vasorelaxation [50], and diuretic action [51]. For detailed review on this aspect, see [41]. In addition to literature reports on the medicinal uses of this plant, we also report here its indications in the treatment of anxiety and labyrinthitis and as anti-snake venom. To the best of our knowledge, these indications remained to be proven experimentally.
In concordance with the traditional use of H. sabdariffa in the treatment of uterine inflammation and pain, its aqueous ethanol extract was shown experimentally to presents anti-inflammatory, uterine antispasmodic activities, and attenuation of intestinal spasm [52–54]. In addition to its confirmed pharmacological activities, its antiobese/weight-reducing [50, 55], hepatoprotective [56–58], anticancer [46, 59, 60], free-radical scavenging [61], antioxidant [42], immunomodulatory [62], lipid-lowering [43, 63] effects and attenuation of oxidants-mediated complications in diabetes [64] have been well documented. Besides, the plant extract is characterized by a very low degree of toxicity [41]. Moreover, apart from its medicinal uses, the plant seed oil was also shown to be a good source of lipidsoluble antioxidants, particularly γ-tocopherol, thus it could have important industrial applications [65].
Solidago microglossa is popularly known in Brazil as “arnica,” “arnica-do-mato,” “arnica-silvestre,” “erva-federal,” “arnica-vulgar,” “erva-lanceta,” and “rabo-de-rojão” [66]. It is usually confused with Arnica montana L., a native of the mountainous regions of Europe, due to the similarity in their medicinal flowers and having the same color (yellow), S. microglossa is not cultivated in Brazil due to it low adaptation to the tropical conditions [66]. In our study, S. microglossa was indicated for treatment of 15 different diseases corresponding to 8 classes of CID, 10th ed. and had a total of 49 citations. The key citations for this plant were its use in wound healing and blood cleansing. Other popular indications found in this study were similar to those previously reported, especially its use in the treatment of wounds, acne, bruises, and stomach-related ailments [67].
Several classes of compounds and metabolites have been isolated from S. microglossa, especially phenols, acetophenones, carotenoids, lactones (helenalin and dihydro-helenalin) [68, 69], flavonoids [70, 71] saponins [72], and polyacetylenes [70]. The cicatrizant activity of the plant’s extract has been confirmed experimentally [73]. Although not mentioned directly by respondents in this study, some lines of evidence suggest important antibiotic activity with the use of S. microglossa, which can justify its indication for uterine inflammation. Morel et al. [74] showed that the essential oil of S. microglossa and three of its components (quercetrin, α-espinasterol, and solidagenone) are capable of significantly inhibiting the growth of Staphylococcus aureus, Staphylococcus epidermidis, Klebsiella pneumoniae, Escherichia coli, Salmonella setubal, Bacillus subtilis, Pseudomonas aeruginosa, Saccharomyces cerevisiae, and Candida albicans [74]. In addition, cicatrizant activity was observed with the administration of the plant’s extract [73]. Its use in ameliorating renal ailments, blood cleansing, and hypotensive and antiparasitic activities may be associated with the presence in high concentrations of tannins [75, 76] and flavonoids in this species [76–79]. Its indication for muscle relaxation may also derive from its antispasmodic effect [80]. Further studies are warranted in these regards.
Other pharmacological properties not mentioned here, but have been established in preclinical studies, include hypoglycemic effect [81] and antitumor activity. In fact, the latter effect has attracted intense interest in the discovery of new chemotherapeutic agents. The extract of S. microglossa demonstrated antiproliferative effect (but not mutagenic) against young shoot cells of onion (Allium cepa) strain [82]. Some of these activities may be related to the presence of secondary metabolites such as helenalin [83].
Although Strychnos pseudoquina is referred to locally as “quinas”, similar to the local name used for species such as Cinchona sp. (source of quinine), it has been shown to be inactive against Plasmodium berghei [84] contrary to its popular use in folk medicine elsewhere [84]. Theoretically, some of the indications may result from the classification bias in the community due to an erroneous popular cultural belief that plants referred to as “quinas” are useful for “anemic” patients infected with malaria parasite. This perhaps helps to explain why the highest indication for this plant in our study was to treat anemia.
Among the components isolated from S. pseudoquina metabolites are isoramnetin, strychnobiflavone, and 11-diaboline metoxidiaboline [85]. Silva et al. [86] demonstrated the gastroprotective effect of S. pseudoquina in models of gastric lesions induced by nonsteroidal anti-inflammatory agents and some necrotizing agents, thus confirming its indication for gastric ulcer and stomach disorders as noted in this present study. On the other hand, its indication in wound healing has not been experimentally confirmed at least in the diabetic wound model in rats [87] or in local hemorrhage induced by Bothrops jararaca venom [88]. Other medicinal uses indicated like “blood depurative” and analgesic effect may be subject of future investigation as a potential agent with antinociceptive and metabolic disorders ameliorating effects. Regarding its toxicity, Santos et al. [81] showed that only the methanol extract (but not dichloromethane) from the leaves of S. pseudoquina have mutagenic effect in Salmonella strains TA98 (−S9) and TA100 (+ S9, −S9) and that it induces formation of micronuclei after acute treatment [81].
Dorstenia brasiliensis, known as “Carapiá” is a perennial herb of the early geological point of view, typical of the fields in southern Brazil, Paraguay, Uruguay, and Argentina [89, 90]. Phytochemical analysis of roots of D. brasiliensis indicated the presence of dorstenic acid A and B (triterpenoids), isopimarane-type diterpenoid, and six different types of coumarins. The two triterpenoids showed moderate cytotoxicity against leukemia cells (L-1210 and HL-60) [91]. Furthermore, some authors have suggested that its use in cutaneow disease (such as psoriases and vitiligo) may be associated with the presence of furanocoumarins in the species of Dorstenia [92]. Bartericin A and B, stigmasterol, isobavachalcone, 4-hydroxylonchocarpin, dorsmanin F, 6,8-diprenyleridictyol, quercetin, quercitrin, amentoflavone [93], psoralen, bergapten (from rhizome), and umbelliferone [94] are some of the compounds isolated this medicinal plant.
Some few pharmacological studies have demonstrated analgesic and anti-inflammatory activities of D. brasiliensis in animal models [95]. These data corroborated the popular use of D. brasiliensis as an analgesic. There is dearth of information confirming its use in the popular medicine use as an anti-inflammatory agent. Moreover, D. brasiliensis may possesses some biologically active compounds similar to other Dorstenia species from the same genus and may thus share similar pharmacological profile. The following compounds and pharmacological activities have been reported in other Dorstenia species: chalcones (D. prorepens and D. zenkeri) [96], furocoumarins (D. bahiensis and D. bryoniifolia), triterpenes (D. bahiensis, D. bryoniifolia, D. carauntae, D. cayapiaa, and D. heringerii) [97]. This is a point to be noted for future research. Some authors have investigated its potential use as antivenom, antiinfective, anti-rheumatic [96, 97] while others established its antitrichomonal [93], antitussive [98], antioxidant [93, 99] and antileishmanial [100] activities.
Scoparia dulcis, popularly known as “vassourinha”, grows wild in backyards, gardens, and fields in Brazil. Phytochemical studies have identified the presence of more than 12 interesting pharmacologically active compounds in this species, namely, scoparic acid A [101], iso-dulcinol, 4-epi-scopadulcic acid B, dulcidiol, scopanolal, dulcinol/scopadulciol, scopadiol [102], scoparinol [103], scopadulcic acid B [104–106], glutinol [107] and scopadulin [105]. Scopadulcic acid B inhibited the effects of tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in vitro and in vivo, and also suppressed the promoting effect of TPA on skin tumor formation, demonstrating stronger effect than antitumor-promoting terpenoids, such as glycyrrhetinic acid [104]. In fact, its cytotoxicity has been investigated against antitumor activity [102] and nerve growth factor-mediated neurite outgrowth and neurodegenerative disorders [103, 108].
The analgesic and anti-inflammatory activities of ethanol extracts of S. dulcis and glutinol have been demonstrated in writhing induced by acetic acid and carrageenan-induced paw edema, respectively [107]. However, S. dulcis extracts were ineffective in the central pain models (tail flick) and paw edema induced by dextran. Another secondary metabolite, scoparinol, also showed significant analgesic and anti-inflammatory activity [109]. In regard to its toxicological effects, it is worthwhile to mention that glutinol and scoparinol markedly potentiated pentobarbital-induced sedation and duration of sleeping time in these two studies mentioned above.
In contrast to its toxicity, S. dulcis seems to possess potential hepatoprotective activity in different models, which have been attributed to its free-radical scavenging potential activities [110–113]. Corroborating with antibiotic use for some infections (like gonorrhea), some authors have investigated inhibition of multidrug resistance (MDR) bacteria, fungi [114, 115], leishmanial parasite [116], and herpes simplex virus type 1 growths [96].
Paradoxically, despite the low citation in gastric ulcer and diabetes treatments in this study, the antiulcer and antihyperglycemic activities of this species are well documented. Inhibitory activities of S. dulcis extracts was demonstrated in pylorus ligature model, histamine- or bethanechol-stimulated gastric secretion, and acute gastric lesions induced by indomethacin [117, 118]. S. dulcis was also demonstrated to inhibit both proton pump (H+, K+-ATPase) and proton transport into gastric vesicles [105]. In regard to its antihyperglycemic effect, experimental evidences demonstrated that S. dulcis extracts reduced blood glucose, glycosylated haemoglobin, prevented decrease in the body weight, and improved glucose tolerance similarly with glibenclamide [119]. Even in the insulin resistance stage, S. dulcis-treated L6 myotubes were found to be more capable of stimulating glucose transport than insulin treatment [120]. In addition, scoparic acid D was able to stimulate insulin secretion and receptor binding in streptozotoci- (STZ-) induced diabetic rats [121].
Luehea divaricata is a native tree of the Brazilian Cerrado popularly known as “açoita-cavalo”. Just as popularly indicated, some studies have reported the following pharmacological activities of L. divaricata: the leaves as used as diuretic, the stems as anti-inflammatory, the bark and aerial parts are used for healing skin wounds, pimples, and for vaginal washes [122, 123].
Phytochemical screening of L. divaricata reported the presence of flavonoids, tannins and saponins and afforded the presence of 3b-p-hydroxybenzoyl-tormentic acid [124], maslinic acid [122], vitexin and glucopyranosylsitosterol, and (−)-epicatechin [123].
The presence of flavonoids and metabolites such as the vitexin [125, 126] and maslinic acid [127, 128] may be associated with the popular indication of its anti-inflammatory properties formation of urate (18) and antitumor (4). Extracts of L. divaricata has been shown to have antioxidant activity and analgesic property [129], lack toxicity in vivo [130], or mutagenicity [131]. Its extract also showed cytotoxicity against tumor cell lines [123]. Due to the high level of citation for the treatment of urate aleviation (18), we believe that its antigout or uricosuric activity may be an important target of pharmacological interest. Another indication prominently cited by the respondents is the use of L. divaricata in the treatment of lung diseases and upper airway. However, there is no scientific evidence on its regulatory activity on cough, while its antibiotic properties also vary. Some authors have demonstrated its inhibitory effect on the growth of dermatophytes [132] but not in other fungi species [123, 129]. In addition, the extract of L. divaricata was shown to strongly inhibit the growth of S. aureus, S. epidermitis, K. pneumonia, and E. coli in a study [129] but showed only moderately in another study elsewhere [123].
It is worth mentioning that although Lafoensia pacari A.St.-Hil. had low relative importance value, all the same, it is among the three plants with the highest informant consesus factor in addition to being a native plant in the region. The other two (S. dulcis and S. microglossa) have been discussed previously.
L. pacari popularly called “mangava-brava”, belongs to the family Lythraceae, is a tree native to the Brazilian Cerrado [133]. It is commonly used for gastrointestinal disorders, wound healing, diarrhea, and kidney problems. In our study, it was referenced for the treatment of seven disorders distributed into five classes of CID, 10th ed. Preliminary phytochemical studies of methanol extract of the stem bark of L. pacari revealed the presence of free steroids, saponins, tannins catechins, pyrogalic tannins (in particular, ellagic acid), triterpenoids, simple phenols, strong and weak fixed acids, alkali, and quaternary amino acids [134–136]. Acute toxicity studies or subchronic oral administration of extracts of L. pacari did not indicate any harmful effects [137]. However, it is also indicated for its adverse reactions and used as an abortifacient, diarrheic, weight loss, and tachycardia. Among the 42 citations for L. pacari, 29 were for the treatment of ulcer, and four and two for gastritis and stomach, respectively. These indications have been confirmed with the use of methanol crude extract of L. pacari and its major active components, ellagic acid, in different experimental ulcer models [138–143]. In addition, the antiulcer activity of the methanol extract (capsules) of L. pacari was confirmed in the clinical trial with 55 patients with dyspepsia [144].
We did not encounter any studies concerning its activities in wound healing, antidiarrheal or alleviation of kidney disorders. This phenomenon of plant selection by local people for certain indications may be, for instance, to consolidate best practice of the medicinal properties of the plants at the expense of using other plants substitute for these indications. In fact, the broad community access to Amazon or Pantanal biome, and the close relationship with the indigenous native populations, promotes a variety of possibilities of ethnobotanical indications. Examples of other popular uses of L. pacari that have been experimentally confirmed includes weight loss [145], anorectic effect [142], antipyretic activity [146], anti-inflammatory [147], antiallergic [148], and analgesic property [149].
It is also worth mentioning other studies focused on the medicinal uses of L. pacari, including its potent antifungal activity [150], have demonstrated that the main compound responsible is found in the methanol extract of this plant. A patent application of lotion with the infusion prepared from the leaves of L. pacari, as a component of the formulation was also solicited [151]. To the best of our knowledge, there is currently no available literature concerning its claims as wound healing, antidiarrheal, or in kidney disorders.
5. Conclusions
The present study identified the several plant species and their medicinal uses in NSACD highlighting significant cultural diversity in the Pantanal region. In fact, one of the important components of this community is the contribution of Amerindian culture, which highlights its importance in the identification of indigenous popular knowledge relevance in the identification of native popular knowledge.
Analytically, the data were categorized according to the highest values of relative importance and consensus among informants, ensuring the best evidence for ethnobotanical bioprospecting of medicinal plants. Thus, we identified seven native species with the highest relative importance, which are H. obovatus, H. sabdariffa, S. microglossa, S. pseudoquina and D.brasiliensis, S. dulcis, and L. divaricata including L. pacari. The three plants with the highest value of consensus among informants were S. dulcis, S. microglossa, and L. pacari.
The preservation of local culture, the practice of traditional medicinal plant species themselves represent important strategies for sustenance of popular knowledge of CAM in the local systems of health care and environmental education. Moreover, ethnobotanical and pharmacological studies provide information essential for guidance in bioprospecting for new drugs of plant origin in the consolidation of therapeutic practices of the community.
Acknowledgments
The authors thank all the informants and staffs of Family Health Programme of NSACD, for the assistance and contributions made throughout ethnobotanical fieldwork, FAPEMAT and CNPq for granting scholarships, researcher, Dr. Rosilene Rodrigues Silva, UFMT Herbarium and Vali Joana Pott (MSc.) of CGMS Herbarium of Federal University of Mato Grosso do Sul, Campo Grande, for technical assistance in identification of plant species, National Institute for Science and Technology in Wetlands (INAU), National Council for Scientific and Technological Development CNPq/MCT, and Pantanal Research Center (CPP) for funding the research work.