Ethnobotanical assessment in protected area from Brazilian Atlantic Forest

In the present study, we conducted a survey on ethnobotanical information of chemical-pharmacological interest, which was acquired via on-site interviews using semi-structured questionnaires with informants in the community in Mucuri Basin in Minas Gerais, Brazil. 184 interviews were conducted with residents with 102 botanical species in approximately 87 genera and 41 families cited. In addition, respiratory system diseases were the most cited, accounting for 26.35% of the cases cited. Lippia alba (lemon balm) was the most cited species with a corrected popular use concordance of about 86.11%. The results suggested that vegetables are important therapeutic resources for the population. Such ethnobotanical studies are fundamental for the understanding and conservation of local culture with regard to the exploitation of medicinal plants. The findings of the present study contribute to the documentation of medicinal species in a Brazilian state characterized by mining, which implies the suppression of vegetation growth or the impairment of regeneration, which could lead to the disappearance of critical and invaluable plant species. The preservation of ethnobotanical knowledge is vital in areas with high human activity and areas undergoing deforestation.


Introduction
Ethnobotany plays a fundamental role in the dissemination of traditional knowledge from medicinal plants and its relationship with scientific knowledge, an association that allows us to understand how plant raw materials are used and their contribution to the development of new pharmaceutical products by populations through previous knowledge of generation to another (Castro, et al., 2021). Brazil is the country with the greatest biodiversity on the planet hosting approximately 25% of the recognized species, which are distributed in six biomes, including the Amazon, Caatinga, Cerrado, Pampas, Pantanal, and Atlantic Forest (Joly, 2011). Particularly, the Atlantic Forest is widely considered to have the highest species richness and rates of endemism on the planet (Ribeiro, et al., 2009). The therapeutic and biotechnological potential of these species could be exploited rationally to conserve the available natural resources. However, according to data from the SOS Mata Atlântica Foundation, due to great losses in the biodiversity of the Atlantic Forest, its size has decreased recently by about 12% from its original size (State Forest Institute, 2017;Costa, et al., 2011).
The present study was conducted in a protected area, which was established via Decree 45.877 of December 31. 2011 (Alto do Mucuri Environmental Protection Area, Minas Gerais state) under the phytogeographic domain of the Atlantic forest hotspot. The biome hosts diverse forest communities under millions of hectares, which are distributed along the Brazilian coast, and it is currently the most degraded biome in the country (Costa, et al., 2011). Particularly, the Mucuri Basin is one of the most devastated Atlantic Forest areas of the state of Minas Gerais, Brazil. This is potentially due to the high levels of mining activity in the region, which could suppress vegetation growth and development or impeding its regeneration (Grant & Koch, 2007). Such conditions could lead to the disappearance of plant species with potentially invaluable applications. In addition, research in the region has led to the discovery of novel species, which suggests that its huge diversity has not been studied exhaustively (Brito, et al., 2019;Maia & Monteiro, 2017;Goldenberg, et al., 2016;Coelho & Valadares, 2019).
The interactions that local communities have had with the biomes over the years have generated a wealth of experience and knowledge about the environments they inhabit with the interest in medicinal plants promoting the accumulation of key information about the environment (Alexiades, 1996;Alexiades & Sheldon, 1996;Lacerda, et al., 2013).
To understand the value of the medicinal plants, it is necessary to understand the communities and their knowledge transmission mechanisms, the environments they inhabit, and the sources of the plants used. Through close and continuous contact with a community, a researcher could obtain information regarding the knowledge of local plants within the community (Almada, 2010;Freitas, et al., 2012).
The findings of the present study could contribute to the documentation of medicinal species in the Mucuri Basin, which is one of the most degraded environments in the state of Minas Gerais, Brazil. This area is characterized by mining, which implies the impairment of vegetation growth and development in addition to its regeneration, which could further lead to the disappearance of invaluable plant species and resources.

The study area
The ethnobotanical survey on potentially medicinal plants in the Mucuri Environmental Preservation Area was conducted on-site from individual approaches by applying a semi-structured questionnaire, combined with informal dialogues.
Here, the studies were conducted in rural communities, in the São Jerônimo -Teófilo Otoni region, in the Sucanga -Poté region, in the Icari -Ladainha region and in the Baixão -Itaipé region, located in the Alto Mucuri, in the Northeast from Minas Gerais state. The information was obtained individually at the informant's residence, from February to December 2017. As inclusion criteria, the resident informants born in the region, aged 18 years or over, who knew and used medicinal plants were   When necessary, we used the technique "walking in the forest" or adapted guided tour by Alexiades (1996). This technique is particularly based on interviews conducted in the field where the researcher follows the informant on a walk, indicating and collecting botanical samples and information about the different uses of plants. All informants were interviewed individually as recommended by Phillips and Gentry (1993) to prevent responses from being influenced by another informant.

Botanical Identification and Collection
The cited species were collected immediately with the interviewee's authorization, observing the representative parts of the botanical material according to their indication of use, as well as parts in the reproductive phase. Subsequently, this material was properly pressed and dried in a greenhouse at an average temperature of about 40°C. After drying the material was herbified according to the techniques suggested by Cunningham (2001). Identification was performed through morphological analysis, through comparison with material deposited in herbarium, dichotomous keys for botanical identification, specialized literature such as Lorenzi (2000), Lorenzi and Matos (2008)

Data processing and analysis
Indications of use for therapeutic treatment were grouped according to biological systems and health problems and symptoms, according to the International Statistical Classification of Diseases and Reported Health Problems (ICD-10, 2015) version 2016, used by the WHO.
From the data obtained, we calculated the Relative Importance Index (RI) of the species cited as medicinal, obtained by calculating the percentage of Principal Use Agreement (CUP) of each species according to the methodology described by Amorozo and Gély (1988). The CUP for each species was found using the formula: CUP = (ICUP / ICUE)*100; where: ICUP is the number of informants who cited the main use, and ICUE is the total of informants who cited the use of the species (Amorozo & Gély 1988).
In order to compare the number of species cited in each locality, Begossi (1996) proposed the adaptation of ecological quantitative methods in ethnobotanical science, which allows evaluating similarities and differences of ethnobotanical knowledge between distinct communities or between groups from the same community.
A comparison between communities was also performed using the plants cited by the informants, obtained from the cluster technique, which makes the ordering of data. Thus, a similarity dendogram was constructed using the Jaccard index, which expresses the similarity between environments, based on the number of common species (Rode, et al., 2009).
To evaluate diversity, the Shannon-Weaver (H') diversity index was used, which is widely used in research that makes comparisons of ethnobotanical studies (Brito, et al., 2011) in different communities and is better known as the Shannon-Wiener index (H).

Social Profile of the Interviewed Community
In the four communities studied, 184 residents were interviewed, aged between 25 and 91 years; being that 54.89% were male. With regard to their levels of education, 39.14% of the respondents did not complete elementary school (Table 1).
The proportion of male respondents who were informants in the present study is inconsistent with the reports of most such studies in Brazil (Amorozo, 2002;Povh & Siqueira, 2013) which have reported a dominance of female informants. The higher proportion of males in the present study could be due to the characteristics of the rural environment studied. While the average age of the informants was 54.20 years, the youngest population, aged between 18 and 29 years, accounted for only 2.17% of the informants.
Regarding the level of education, a large proportion of the population did not complete basic education, which could be due to a need to work to boost family income.

Ethnobotanical Survey
The  6 Other studies conducted in rural communities in the Atlantic Forest biome in the state of Minas Gerais have also reported the predominance of species belonging to the Lamiaceae and Asteraceae families (Alves & Pohv, 2013); these families have a cosmopolitan distribution and have potential therapeutic, nutritional, and economic applications (Silva & Andrade, 2013).

Sampling and Estimated Wealth
RI index values between 0 and 24 correspond to rarely used species, between 25 and 49 to intermediately use species, and between 50 and 100 to widely used species. Most of the cited species (66.67%) had RI indices between 0 and 24. Species with RI values between 25 and 49 accounted for 26.47% of the cited species, while species with values between 50 and 100 accounted for only 6.86% of the cited species, representing seven out of the total 102 species listed in the area. Lippia alba (lemon balm) was the most cited species in the present study, with a CUPc of 86.11 (Table 2). Various studies conducted in other areas of the Atlantic Forest also reported L. alba as the most commonly cited species (Brito & Senna-Valle, 2011;Oliveira, 2015).
Leaves were the most commonly used plant organs in preparations for medicinal purposes. Leaves were cited the most (47.10%) for use in the treatment of diseases, followed by roots (10.14%) and flowers (7.97%) ( Figure 3A). Other studies have also reported leaves to be the major organs used for therapeutic purposes (Messias, et al., 2015;Guimarães, 2016;Lima, 2015). Hence, the use of leaves implies that plant structure and survival are not compromised. Regarding the selection of methods of preparation, the long-term activity of the active ingredients in the species should be taken into account.

Plant Material and method of preparation used by communities
Concerning the plant organs used in plant preparations for medicinal purposes, it was observed that the leaves of the species are the most used. The leaves showed 47.10% of citations have a higher predominance of use for the treatment of diseases, followed by root (10.14%) and flower (7.97%) ( Figure 3A). This fact has been verified by other studies in which leaves are the main botanical part used for medicinal use (Messias, et al., 2015;Guimarães, 2016;Lima, 2015).
As for the method of preparation, the survey showed that the main form of consumption of the plant is the preparation of tea. Decoction with 46.92% is the most used form of preparation. Infusion (25.93%) is the second most used form in communities ( Figure 2B). Other authors such as Borges and Bautista (2010)

Indications for therapeutic use of medicinal plants
The  CID -1 infectious and parasitic diseases; CID-2 neoplasms (tumors); CID-3 blood and hematopoietic organ disorders and some immunity disorders; CID-4 endocrine, nutritional and metabolic diseases; CID-5 mental and behavioral diseases; CID-6 nervous system disorders; CID-8 ear and mastoid apophysis diseases; CID-9 blood circulation diseases; CID-10 respiratory tract diseases; CID-11 digestive tract diseases; CID-12 skin and subcutaneous tissue diseases; CID-13 skin and subcutaneous tissue diseases; CID-14 genitourinary tract diseases; CID-18 Symptoms, signs and abnormal findings of clinical and laboratory examinations not elsewhere classified; CID-19 injury, poisoning and some other consequences of external causes; CID-21 factors that influence health status and contact with health services. Source: Authors.
Similar studies have been reported indicating that respiratory system disorders and gastrointestinal system disorders correspond to the highest indications for use of these medicinal plants (Brito, et al., 2015).

Discussion
Ethnobotany, a field of study that explores the interrelationships between plants and human societies based on anthropological, ecological, and botanical dimensions, enhances our understanding of human societies and how they interact with plants (Albuquerque, et al., 2002;Soldati, 2013;Almeida, et al., 2009). Such ethnobotanical surveys provide information from local communities with regard to medicinal plants could guide chemical and pharmacological studies carried out in laboratories, which could facilitate the discovery of novel drugs and herbal remedies.
Several factors have been evaluated and are described in the text, which contribute to understand the dissemination of traditional knowledge, the preservation of flora in active human activity ecosystems and to conduct bioactivity and chemiodiversity studies in order to confirm the therapeutic potential of the species and discover the potential of the molecules responsible for this bioactivity.
Among the four communities studied, most of the respondents were aged 60-69 years and less than 50% of the respondents had not completed elementary school, indicating that the ethnopharmacological knowledge obtained was passed down through generations (Amorozo, 2002;Povh & Siqueira, 2013). In addition, the results of the present study indicate that the majority of the informants were males, which is consistent with the characteristics of the rural environment studied, mostly composed of small farms, characteristic of subsistence farming, where property is often inherited from descendants. Therefore, the heads of households (male) are often present around the home. In addition, the interview was conducted on a Saturday, which could have influenced the number of males reported, considering the increase in incidences of violence and fraud (report by some informants) in rural areas.
In a survey on medicinal plants conducted by Freitas, et al., (2012), the average age of the informants was 51.75 years. In the present study, young individuals aged 18 to 29 years had a low level of participation, representing only 2.17% of the informants. Interviewees generally referred the researchers to other family members, who were often the oldest members with the relevant knowledge to answer the questionnaires.
With regard to the level of education individuals, in rural areas often encounter the dilemma of choosing between work and study. Many young people opt to work, as they often need to complement family income. In addition, in the capitalist societies they live in, having a job is critical for social recognition (Queiroz, 2009).
More recent works such as Alves and Pohv (2013) investigated the medicinal plants of a rural community in the Atlantic Forest in Minas Gerais and the predominant plant families were Lamiaceae and Asteraceae, in Ouro Preto city (Minas Gerais. Brazil), in a study by Messias, et al., (2015). Asteraceae, Fabaceae, and Lamiaceae were the most dominant families.
The high frequency of the species from the families could be associated with their wide distribution, the high number of species in the families, and their economic importance. The high numbers of the Lamiaceae, for example, could be explained by its cosmopolitan distribution and its broad medicinal applications (Mosca & Loiola, 2009;Freitas, et al., 2012;Paulino, et al., 2012;Alves & Povh, 2013;Moreira & Guarim Neto, 2015).
RI values between 0 and 24 correspond to rarely used species, between 25 and 49 to intermediately used species, and between 50 and 100 to widely used species. According to the results, most of the cited species (66.67%) has an IR between 0 and 24. Species with IR values between 25 and 49 accounted for 26.47% of the cited species, while species with IR values between 50 and 100 accounted for only 6.86% of the cited species, which were 7 out of the 102 species in the area. Different studies conducted in other areas in the Atlantic Forest also reported similar results (Brito & Senna-Valle, 2011;Oliveira, 2015).
The H′ index, a factor widely used in ecological studies, was 4.09 for the Icari region, 4.19 for the Baixão region, 3.98 for the São Jerônimo region, and 4.06 for the Sucanga region. In a study by Pereira, et al., (2011) in Gaspar Alto Central -SC, the H′ value reported was 3.74, In Itacaré -BA. Pinto et al. (2006), in studies on medicinal plants in rural communities of the Atlantic Forest, reported a value of about 4.21.
Different plant parts are used by communities for medicinal preparations. In the present study, leaves, with 47.10% of citations, were predominantly used to treat diseases, followed by roots (10.14%) and flowers (7.97%). Other studies have also reported the predominant use of leaves (Messias, et al., 2015, Guimarães, 2016Lima, 2015). The predominant use of leaves in medicinal preparations could be due to the relative ease of use of leaves in preparations when compared to other plant parts, greater availability throughout the year (Spagnuolo & Baldo, 2009), or according to Gonçalves & Martins (1998), relative ease of collection and the higher chances of survival of a plant.
Regarding the methods of preparation of medicinal products, the survey revealed that the main form of consumption of the plant is tea. Decoction (46.92%) was the most widespread preparation followed by infusion (25.93%). The data are consistent with the findings of other studies (Borges & Bautista, 2010;Mota & Dias, 2012;Ferreia, et al., 2014;Soares, et al., 2009).
The use of leaves in medicinal preparations has relatively low negative impacts on ecological systems. According to Pilla, et al., (2006), the widespread use of leaves that are mostly collected manually for the preparation of "tea" is beneficial based on conservation and sustainable development perspectives, since the collection of leaves would not adversely impair plant development or result in plant death. The removal of other plant parts such as stem bark is largely destructive because it compromises the conductive systems, in turn adversely affecting the development and longevity of the plant (Rodrigues & Carvalho, 2001).
The method of preparation may be related to the type of organ of the plant used, considering that leaves often bear active thermolabile compounds.
Indications for exploitation of the botanical species for therapy were grouped according to biological systems, and health problems and symptoms based on the ICD-10, 2015 version 2016, used by WHO. The various uses cited by the informants were classified into 16 categories. Most of the diseases that could be treated with plants used by the communities in the studied areas were in category X -Diseases of the respiratory system with 26.35%, followed by diseases of category XI -Diseases of the digestive system (17.41%) and category XVIII -Symptoms, signs and abnormal clinical and laboratory findings 8.48%, not elsewhere classified. Within the f diseases of the respiratory system, influenza was the most cited disease, and it had the highest indication with 47 different plants for treatment. Brito, et al., (2015) also obtained similar results, where the respiratory system and its disorders (influenza, cough, cold) accounted for 24.8% of citations, followed by gastrointestinal system disorders (11.1%), and undefined pain (8.3%). In addition, other studies have reported similar results (Amorozo, 2002;Begossi, et al., 2002;Giraldi & Hanazaki, 2010;Cunha & Bortolotto, 2011).
The application of species in therapeutic activities requires the selection of species that are effective and safe, either based on tradition or on scientific validation. In addition, the pharmacological properties of species that have diverse applications and are cited more frequently should be investigated further. The high numbers of species among the three families demonstrate their potential medicinal, economic, and nutritional applications, in addition to their potential to supply medicinally functional biomolecules, as they have key secondary metabolites that could be explored through pharmacological studies.

Conclusion
The findings of the present study contribute to the documentation of medicinal species in a Brazilian state characterized by mining, which implies the suppression of vegetation growth or the impairment of regeneration, which could lead to the disappearance of critical and invaluable plant species. The preservation of ethnobotanical knowledge is vital in areas with high human activity and areas undergoing deforestation. To the best of our knowledge, this is the first report on the use of plants for medicinal purposes in rural communities in the region of the Mucuri Basin area in the Minas Gerais region, Brazil. Therefore, the results of the survey could facilitate future ethnobotanical and pharmacological studies in the region and chemical studies exploring the active ingredients in the cited species.