Ethnomedical knowledge among the “Quilombolas” from Oriximiná, Brazil, with a special focus on plants used as nerve tonics

By definition, the “remnants of quilombos” or “quilombola” communities are ethnic groups with a historical background and presumption of black ancestry related to resistance to oppression suffered historically. Their close contact with nature over centuries and their geographic isolation has given these community members a vast knowledge of medicinal plants. This work focused on plants with indications to “rejuvenating” or used as “neurotonic”, employed by the quilombola communities of Oriximina to prevent forgetfulness and improve memory. The methodology used was semistructured interviews, participating observation, walk-in-the-woods, as well as quantitative techniques of data analysis such as salience index (S), relative importance of species (RI), and the corrected major use agreement (MUAc). Thirty four interviewed people related 254 ethnospecies totalizing 2508 use indications. Among these, 227 species were identified, belonging to 211 genus and to 77 botanic families. The ethnodirected method of free-list focusing on forgetfulness, youthfulness, elderness, “head weakness”, “weakness of mind”, “weakness of men”, “nerve tonic”, aphrodisiac, among other terms, was applied to the informants, leading to 36 ethnospecies. This diversity identifies a clear relationship between their traditional knowledge and the mega biodiversity of the region.