**3. Medicinal plants and indigenous people in the Peruvian Amazon**

 The Amazon lowland rain forest provides multiple benefits to its inhabitants [15]. According to Schultes [16], rain forests have an incalculable value as an untapped emporium of germplasm for new commercial plants. For example, to the inhabitants of Mishana (a community near Iquitos), the tropical forest provides timber resources (e.g., sawlogs and pulpwood) and several forest products such as edible fruits, oils, latex, fiber, and medicines. The yield of these forest products is provided by 72 species (26.2%) that are sold in the Iquitos market [17]. In addition, it is estimated that ~4400 native plant species of the Peruvian flora are used by inhabitants for 49 different applications [18]. With reference to bioactive plants, it was reported that more than 1300 species are used by natives in the northwest Amazon as medicines, poisons, or narcotics [16]. To date, however, the list of medicinal plants useful for the discovery and development

**Figure 2.**  *Selected ethnic groups from the Peruvian Amazon.* 

 of drugs is fragmentary and incomplete, because the ethnopharmacological surveys conducted in the Peruvian Amazon are sporadic and scarce. Recently, we elaborated a partial database of medicinal plants of the Peruvian Amazon, which is based on the few available ethnobotanical studies [9–12, 19–25], one list of the Research Institute of The Peruvian Amazon (IIAP) and surveys carried out by our research group in the *Pasaje Paquito* (the main center for commercialization of medicinal plants in the Loreto region, Iquitos). The medicinal plant database includes 1410 species belonging to 157 plant families; these taxonomic assignations were verified with the Plant List database (http://www.theplantlist. org/). Of these, the top 10 families by number of medicinal plant species are Fabaceae (137), Asteraceae (80), Rubiaceae (57), Araceae (53), Piperaceae (51), Solanaceae (51), Euphorbiaceae (47), Apocynaceae (39), Bignoniaceae (39), and Clusiaceae (32). In addition, this database reveals that the plant families with the highest number of medicinal uses are Fabaceae (272), Asteraceae (244), Rubiaceae (197), Euphorbiaceae (180), Piperaceae (179), and Solanaceae with 166 medicinal uses (**Figure 1**).

It is paradoxical that only some ethnic groups were evaluated to date for ethnopharmacological surveys, given the Peruvian Amazon's ethnic diversity (**Figure 2**). According to a recent national census, the indigenous population of the Peruvian Amazon consists of 332,975 inhabitants that include 13 linguistic families that are grouped into 51 ethnic groups. Of the total number of communities registered, 21 are polyethnic [26, 27]. In all these ethnic groups, the millenary knowledge of medicinal plants used to combat common diseases is a fundamental component within the indigenous health systems, which has been maintained from generation to generation. However, due to the transculturation by modernization and globalization, this ancestral knowledge is being lost [15]. Consequently, it is necessary to implement strategies to preserve this invaluable knowledge for the benefit of humankind.
