Plantas medicinais e conhecimento tradicional ribeirinho : uma investigação etnobotânica e etnofarmacológica na Microrregião do Norte Araguaia, Mato Grosso, Brasil

Abstract

The micro-region of North Araguaia of Mato Grosso consists of 14 municipalities covered under the Amazon and Brazilian Savanna, bathed mostly by the Araguaia and Xingu rivers and holds enormous ethnic and cultural diversity. Objectives: To survey, identify and record medicinal plants species used by riverine dwellers of the North Araguaia Microregion and select native plants for further chemical and pharmacological studies through consultation of literature. Materials and Methods: This was an ethnobotanical study, of cross-sectional type, by non-probability sampling (n = 60), in which snowball method was employed for the selection of riverine dwellers locally recognized as local experts in the use of medicinal plants, distributed in 14 municipalities of the Microregion. Information was obtained in the period from July to November 2013, through interviews, using a semi-structured form, containing socio- demographic, ethnobotanical and ethnopharmacological variables. The relative importance (RI), the informant consensus factor (ICF) and analysis of main components (APC) and Chi-Square (X2) were used for comparison among taxonomic groups and boy systems. The research was initiated only after compliance with all ethical aspects, together with the informants and federal agencies. Results: Riparian respondents presented aged between 35 to 85 years, majority (53,2%) come from other regions of the country other than the Midwest. 55% male, 70% were married, 58.3% with 1-5 children, majority (51,7%) retired, 36,7% survive with no more than a minimum wage / month, 45% white, 61.6% Catholics and 75% learned to use medicinal plants from their family members. 309 plant species belonging to 85 botanical families were cited. 73% of the plants were native, Fabaceae (11.3%), Lamiaceae (6.8%) and Asteraceae (5.8%) were the most representative. The dominant habit was tree (38,8%), the leaves were the part most used (28.9%) and the predominant form of preparation was infusion (31.3%). The species with the highest number of use citations were Copaifera langsdorffii Desf. (133) Lafoensia pacari A.St.-Hil. (131) and Cecropia pachystachya Trécul. (126), and the plants reported in the survey were indicated for 18 of the 22 categories of diseases ICD-10, most notably infectious and parasitic diseases (DIP, Chapter I), by 16.6% of the use of quotations. Among the plants mentioned for this category of disease (PID), Chenopodium ambrosioides L. was the species with the highest use of citation (50). IR values ranged from 0.1 to 1.9, with highest values C. langsdorffii, C. pachystachya and L. pacari (1.9, 1.8 and 1.7, respectively). As for the ICF, the highest values were evidenced for DIP (0.79), DSR (0.79) and DSD (0.78), being that most native plants to treat such cited disease categories were Bidens pilosa L., Vernonia ferruginea Less and L. pacari respectively. ACPs showed that the plants of the family Fabaceae were the most used for categories of diseases more recurrent in the study (DIP, DSG AND DSD). It was also found that the body's systems SND, DSD, LEV, DIP, DSG, DSO, DSR and DMC show to be strongly correlated among themselves, in such a way that tend to be treated by the same plants. The analyzes of X2 suggested that the categories of diseases were in some way different from each other in relation to the species of the families used for their treatments. Of the 9 native plants investigated, C. langsdorffii and Brosimum gaudichaudii were outstanding, because in addition to having been widely studied from phytochemical and pharmacological point of view, they have been marketed as pharmaceutical products and even have a patent registration. Conclusion: The riverine local experts in the microrregion of Northern Araguaia utilize a wide diversity of medicinal plants in health self-care, predominantly those used in the treatment of DIP. In fact, the therapeutic potential of some of these plants have been scientifically validated. However, there are others whose pharmacological effects and safety have not been properly investigated. It was also observed that the respondents do not use plants at random, but that it is based on well-established criteria for the selection of species used for medicinal purposes. Thus, the present study in addition to serving as a basis for future studies on chemical, pharmacological and agronomic bioprospecting may also contribute to development of management strategies, conservation and sustainable use of medicinal flora of the Microregion.