Scientometric analysis of scientific production on the genus Campomanesia Ruiz & Pav. (Myrtaceae) and most studied species-research trends involving native Brazilian plants

Brazil has rich biodiversity, harboring native plants with potential for medicinal use, including species of the Campomanesia genus. Although public policies to encourage phytotherapy advocate the best use of plant biodiversity, most species listed in official forms and monographs are exotic species. Thus, the aim of this study is to identify research trends involving the Campomanesia and main species, using scientometric tools, so that, by viewing and knowing the scientific production on the genus and species of pharmacological interest, possibilities for research with native species so that they can be integrated into Brazilian’s unified health system (SUS). The research resulted in 302 publications up to September 2021. Bibliometric analyzes on genus were then carried out with data from the WoS platform and social network analysis through of scientometric mapping, using the Vosviewer (VOS) application. Species of the genus with more than 10 publications indexed in WoS were also analyzed. Brazil leads research on the genus and C. xanthocarpa (120/302); C. adamantium (70/302); C. pubescens (33/120); C.phaea (25/302); C. lineatifolia (21/302) and C. guazumifolia (10/302) were the species with the highest publication volume. It is the first work that analyzes the scientific production on these genus of Myrtaceae family and the aforementioned species, which revealed itself a promising field of research, yet little explored, which might encourage new studies aimed at better use of Brazilian biodiversity and the safe and effective use of native plants that may bring benefits to people's health and well-being.


Introduction
Brazil, in its continental dimensions, covers areas with different edaphic, climatic and phytophysiognomic conditions. This variability favored the establishment of different ecosystem formations. The high levels of diversity and degradation due to agropastoral occupation meant that the country had three of its biomes listed among the 25 biodiversity hotspots on the planet (Myers, 2000). In addition to the immense variety of flora and fauna, the country also stands out for its socio-biodiversity, with an invaluable wealth of knowledge and cultures, represented by more than 300 indigenous peoples, quilombola communities, among others that have knowledge about the use and preservation of natural resources. In addition to traditional knowledge and availability of natural resources, the implementation of new technologies can enable the country, in a sustainable way, to increase the research and development of products of natural origin with diverse applicability, especially aimed at improving health and quality of life of people (Valli et al., 2018). However, despite all this heritage, Brazilian biodiversity is underutilized. Most of the national economic activities are based on exotic species in agriculture, livestock and also in extractivism (Brasil, 2021).
The best use of our plant biodiversity is one of the great challenges contemplated in Brazilian public policies. In 2006, the National Policy on Medicinal Plants and Herbal Medicines was created, which established detailed guidelines in the National Program of Medicinal Plants and Herbal Medicines through Interministerial Decree 2.960/2008 (Brasil, 2008), involving 10 ministries. The main objective of the Policy and the Program was to guarantee the Brazilian population safe access and rational use of medicinal and herbal plants, promoting the sustainable use of biodiversity, the development of the production chain and the national industry (Brasil, 2015). Although the guidelines of the herbal medicine policy converge towards the enhancement of local biodiversity, most of the species listed in Brazilian's national healthcare system (SUS) programs are exotic species (Martins et al., 2019;Medeiros, 2013).

The interest in researching native Brazilian plants of medicinal and pharmacological interest dates back to Brazil
Colony, in the court of D. João VI, when the French naturalist Auguste de Saint-Hilaire (1779-1853, on his trips to the interior of Brazil, produced a scientific work that cataloged 283 plants distributed in 53 families. The Fabaceae family was the most representative in the work, with 20 species, followed by Solanaceae, Rubiaceae and Myrtaceae with 12, 10 and 9 species respectively (Brandão et al., 2012).
The Myrtaceae family comprises 5,970 species distributed in 145 genera, including the Campomanesia genus, home to 38 species (The Plant List, 2013), one of them, Campomanesia pubescens, is present in the work of Saint-Hilaire (Brandão et al., 2012). The species of the genus are widely distributed in Brazil and are known for the sweet-acid taste of their fruits. As for the common secondary metabolites for the genus, the phenolic compounds, anthocyanins, chalcones, coumarins, tannins and saponins stand out, in addition to the presence of volatile compounds in its leaves. Evidently there is phytochemical variation between species, but the presence of these classes of compounds could explain the traditional therapeutic use, which is why some species have aroused the interest of researchers, such as: Campomanesia xanthocarpa, Campomanesia adamantium, Campomanesia guazumifolia, Campomanesia reitziana and Campomanesia lineatifolia. Despite the growing publications showing the importance of the genus, not only in the food field, but also in pharmacological applications, there is still a vast field of research to be explored to investigate its potential, especially of native species (Duarte et al., 2020;Lescano et al., 2019).
A research modality that has been standing out in the field of evaluating scientific production and research trends is the scientometric study, whose term was coined by Russian scientist Nalimov and collaborators in the late 1960s. It is the application of quantitative methods on the development of science as an information process, in order to measure scientific production on a given topic, using data analysis tools that allow insights indicative of research trends, such as: research areas, authors, countries, impact of publications, research institutions, funding agents, among others, and the correlations between each variable (Nalimov & Mulchenko, 1971;Van Eck & Waltman, 2010).
Bibliometric research involving scientific production on ethnobotany suggests that this type of study can help formulate public policies trat promote the best use and conservation of biodiversity (Ritter et al., 2015). Based on the foregoing, the aim of this study was to analyze, with the aid of scientometric tools, the scientific production of Campomanesia, identifying research trends involving the genus and species of greatest interest so that this overview can stimulate new studies aimed at the use of native plants with biological activities for traditional use and as herbal medicines and thus can be contemplated in public policies to encourage integrative and complementary health practices.

Methodology
Survey data were obtained from the Web of Science (WoS). The keyword "Campomanesia" was tested in the "Topic" field of WoS in a previous search along with all the synonyms that appear in The Plant List platform. Only the main name produced results, thus, the search for the term "Campomanesia" in the topic dated until 09/30/2021 generated data for the analysis and scientometric mapping on the genus.
For the analyzes on the species, the term "Campomanesia" was used until 09/30/2021 and in the Filter field, each of the accepted names of species cataloged in "The Plant List" was added separately in spreadsheets organized in order decreasing in the number of publications. For this research, species with 10 or more publications were selected. Then, a Database was generated with each of the species selected according to the established criteria, which were: C. xanthocarpa, C. adamantium, C. pubescens, C.phaea, C. lineatifolia and C. guazumifolia. The information obtained on the indicators for the genus and species was analyzed separately. For the general bibliometric analyses, the WoS analysis tools were used and for the analysis of relationship networks and scientometric mapping, the VOSviewer application was used, based on the technique of visualization by similarities (VOS). Research, Society andDevelopment, v. 11, n. 1, e19111124639, 2022 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v11i1.24639 4 In the present study, for the analysis of relationship networks related to the Campomanesia genus, bibliographic coupling and cocitation for citation relationships were used. Figure 1 schematically represents the analysis tools used in this study.
The method applied in scientometric mapping comprises three categories of analysis: citation relationships, word cooccurrence and co-authorship relationships (Li et al., 2021;Van Eck & Waltman, 2010). Citation relationships are the basic principle of scientometric mapping, as it is assumed that the more cited, the more relevant the work (Van Raan & Tijssen, 1993).
Citing articles are mapped by bibliographic coupling, while cited articles are mapped by co-citation. Other important tools in scientometric analysis are co-word mapping and co-authorship mapping related to organizations. The first identifies the network of keywords used simultaneously by the authors and thus can reveal the main words and themes about the researched subject.
The secopond reveals the relationship and collaboration networks between authors and institutions (Garfield, 2001).

Year and type of publication
The search for the term Campomanesia in the "Topic" field of WoS resulted in 302 publications. The first article indexed in the database was published in 1982, with the title "The development of the fruits and seeds of Campomanesia (Myrtaceae)", published in the periodical Brittonia (Landrum, 1982). The year 2020, a year strongly marked by the Covid-19 pandemic, was the most productive, with 41 publications. Still under the impact of the pandemic, the year 2021 has already registered 29 publications up to the month of September. Figure 2 illustrates the evolution of research on gender over the years, both in number of publications and the evolution of citations and illustrates other numerical information obtained from WoS, such as types of publications, number of countries related to the research; lists open access publications as well as citation report data. Most of the publications found were of the article type (275 out of 302, which comprises 91%); there were 11 review articles (3.7%) and the rest were meeting abstracts, conference articles, notes, among others. The significant proportion of the number of original articles in relation to review articles suggests that studies with plants of the genus are still scarce, which may mean a potential field of research that is still little explored.  (Brasil, 2006), influenced the production of studies in this field.

Affiliations, countries, regions, research funding and collaboration networks between institutions
Brazil concentrates most of the studies on the Campomanesia, with 277 publications (91.7%), followed by the United States of America (USA) with 18 publications; Colombia, 9 studies; Sweden, 5; Spain 4; Argentina, Austria, France, Pakistan and Scotland with 2 publications each and 13 other countries with only one publication. Among these are some with an important history in research on medicinal plants such as China, India, Germany, Japan and Peru. As the species of the genus has an important geographic distribution in Brazil, in areas of tropical, subtropical and Cerrado forests (Landrum, 1986). Brazil's greater interest in researching the species of the genus is justified, and perhaps because of that, the funding agencies that most fostered research were precisely the Brazilian ones. Brazilian's National Council for Scientific and Technological Development (CNPq) and the Coordination for the Improvement of Higher Education Personnel (CAPES) contributed to the development of 71% of the research, with 119 studies funded by CNPq and 94 funded by CAPES, which corresponds to 39.7% and 31.3% respectively. Table 1 presents the ranking of affiliations that generated at least 5 publications and their origin (by region of Brazil or foreign country).    This study also analyzed the relationships between authors and institutions, represented by Figure   Source: Authors.  Table 3 and Figure 5 which respectively illustrate the ranking of journals with 5 or more publications and their Research, Society and Development, v. 11, n. 1, e19111124639, 2022 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v11i1.24639 8 respective Impact Factor according to the Incites Journal Citation Reports (JCR) belonging to Clarivate Analytics and the network map involving the relationships of co-citation between journals, based on the strength of term density. The data presented lead to the reflection that titles with a higher Impact factor achieve greater relevance in terms of impact on citations than, for example, the journal with the highest number of publications, despite having a smaller number of publications. In the case of this study, the Food Research International and the Journal of Ethnopharmacology are the journals with higher impact, with an Impact Factor of 6,475 and 4,360 respectively.   Source: Authors. Table 4 illustrates the 10 most cited articles, by year of publication, the total number of citations, as well as the evolution in the number of citations in the last 5 years, with the data for the year 2021 referring to the month of September when the data were collected. Reading the titles, abstracts and keywords shows that of the 10 most cited articles, 8 investigate biological activities, demonstrating the pharmacological interest of the species of the genus; one of the articles reveals interest in cultivation and propagation and the other in the field of food and beverages, which investigates the potential of C. pubescens fruits in the production of fermented beverages (Duarte et al., 2009). In this list of articles, the most studied species was C. xanthocarpa (5 out of 10 publications), 2 of which related to antioxidant potential, 2 related to weight loss (one of which also assesses the improvement of biochemical parameters such as blood glucose and lipid profile) and one that demonstrated an antiulcer effect.

Most cited articles and co-occurrence relationships of keywords between authors
Another species present in the list of the 10 most cited articles is C. adamantium (one of the researches used the synonymous term Campomanesia cambessedeana with 2 publications. One of them investigates antioxidant and antiproliferative activity (Malta et al., 2013) and another investigates anti-inflammatory and antinociceptive activity (Ferreira et al., 2013).
The co-occurrence analysis of keywords in the database on the Campomanesia genus is described in Figure 6. The genus' database generated a total of 1507 keywords. It was limited the minimum number of occurrences per word to 5, which generated 75 items divided into 6 clusters, 857 links, with 1608 being the total strength of the link. The overlay view displays keywords by publication time, which allows inferences about current research trends on the topic. It is observed that the term Myrtaceae appears more significantly because it is the family to which the genus belongs and may also reveal the interest of researchers in the family that houses numerous species of interest in the most diverse areas (Farias et al., 2020). The Campomanesia xanthocarpa species also appears relevantly (34 occurrences, 45 links) linked to words that denote potential biological activities, such as inflammation, oxidative stress, bioactive compounds, obesity, cytokines and nitric oxide (Salmazzo et al., 2021;Souza et al., 2019). It is noted that the terms related to antioxidant activity are yellow, indicating that they are the most recent research, as well as the term savannah (16 occurrences, 29 links), suggesting a research trend towards biological activity with species from this Brazilian biome. Campomanesia adamantium was also a relevant term (13 occurrences, 22 links), in lilac color, which indicates older research that may be related to the traditional use linked to antimicrobial activity, but also related to words that indicate antioxidant and anti-microbial activity, but also related to words that indicate antioxidant and antiinflammatory activities in recent research . The term "antimicrobial activity" had 11 hits and 35 links, while the term "antioxidant activity" comes up with 51 hits and 57 links.

Contributions on authors and network collaboration between authors (bibliographic coupling)
Research involving the Campomanesia genus is concentrated in a few researchers, as shown in Table 5 (9) and Plos One (7).   Source: Authors.

Co-citation networks and cited references -theoretical pillars
The analysis of the co-citation network, together with the cited references, indicate the theoretical pillars that underlie the database research on the Campomanesia genus. Figure

Most researched and researched species of the campomanesia genus in the last 5 years
For the analysis of the most searched species in the WoS database, it was added a filter with the name of each of the 38 species with names accepted by The Plant List platform (theplantlist.org), considering synonymous terms, then it was selected species with 10 or more publications. The species C. xanthocarpa and C. adamantium lead the ranking with 120 and 70 species respectively. Table 6 illustrates the 6 species with the total number of publications; the number of publications from 2017 to September 2021 and the representative percentage of studies in the last 5 years. It is observed that the species C. guazumifolia, from this list, is the one with the fewest studies, but the majority (80%) occurred in the last 5 years, suggesting a recent interest in its potential. On the other hand, C. lineatifolia presented only 1 study in the last 5 years, more specifically in 2021.  (Vinagre et al., 2010); antiulcerogenic (Markman et al., 2004), antinociceptive (Leandro et al., 2020); anti-obesity (Biavatti et al., 2004;Dickel et al., 2007); antidiarrheal (Souza-Moreira et al., 2011); antimicrobial (Capeletto et al., 2016), among others.

C. xanthocarpa -Co-occurrence network analysis by keywords
The co-occurrence relationship of words in research on the species shows the main keywords, and the relationship between them, which allows for the identification of the main themes addressed by the articles. For the construction of the VOS map, shown in Figure 8, we selected the All Keywords option and limited it to 3 occurrences per word, which generated 772 words in 61 items, divided into 7 clusters, 380 links, with a total link strength of 680. Figure 9 shows the overlay map visualization, indicating the use of terms over the years, which may suggest current research trends. It is observed that cluster 1, in green, presents the relevance of the keyword "Antioxidant activity", which is also related to cluster 3 with the word "Oxidative stress" in yellow, both are linked to related terms such as "polyphenols", "phenolic compounds", "atherosclerosis", "quercetin", among others, indicating a strong research tendency of the species for this activity. Other words related to biological activities that appear relevantly are: "antimicrobial activity", "obesity" and "cholesterol".  (Sá et al., 2018), antioxidant (Coutinho et al., 2010), anti-inflammatory and anti-nociceptive (Viscardi et al., 2017).

C. adamantium -Bibliometric Analysis
The

C. adamantium -Co-occurrence network analysis by keywords
The analysis of the occurrence of keywords for the species C. adamantium in the VOS is shown in Figure 10 and was limited to 3 occurrences per word. Therefore, from 392 keywords found, 41 items were generated, 6 clusters, 242 links and 376 the total strength of the link. The overlay view shows that the most recently used words are related to antioxidant activity and antiproliferative activity. The term "Savannah" (in yellowish-green) appears in a relevant way with 12 occurrences, which may indicate a research trend in native plants of this biome with potential biological activity, among them: antioxidant activity (12 occurrences), antimicrobial activity (4 occurrences) and antiproliferative activity (3 occurrences).  (Fern, 2014b). Some biological activities are attributed to the species, such as antimicrobial ; antioxidant (Chang et al., 2011); metabolic dysfunctions (Cardozo et al., 2018) and even anxiolytic and anti-depressant activities (Villas Boas et al., 2020).

C. pubescens -Bibliometric Analysis
The search for the species name in WoS presented 33 results, 29 articles and 2 reviews, 1 correction and 1 Conference  Figure 11 illustrates the map of keyword co-occurrence analyzes for the species C. pubescens. The minimum number of occurrences of keywords considered for this analysis was 2. Therefore, the 212 keywords were distributed into 35 items, 6 clusters, 154 links and 203 total link strength. Figure 11 represents the co-occurrence networks of these words in an overlay view. It is observed that the term Campomanesia xanthocarpa with 5 occurrences and the term Campomanesia lineatifolia with 3 occurrences, suggesting that these species have been researched together with C. pubescens. Note, as in the species described above, the relevance of the terms linked to antioxidant activity (8 occurrences, 20 links) and oxidative stress (2 occurrences, 8 links) in shades ranging from light green to yellow, indicating the current trend of search. The term "antimicrobial activity"

C. pubescens -Co-occurrence network analysis by keywords
suggests the investigation of this biological baactivity for the species (2 occurrences, 12 links). The term "essential oil" (6 occurrences, 17 links) linked to these activities may indicate that the essential oil was used for the research of antioxidant and antimicrobial activity.

Campomanesia phaea (O.Berg) Landrum
C. phaea is an endemic species native to Brazil, found in temperate and semi-temperate zones in the states of São Paulo and Rio de Janeiro, currently classified as vulnerable to extinction risk by the World Conservation Monitoring Center ( 1998).
According to the Tropical Plants Database (2021), it is a species rarely found in natura, being often cultivated, within its native distribution area, by local communities that appreciate the pleasant acid-astringent flavor of its fruits, known as "cambuci", which can be consumed fresh and in jellies and ice cream. It is a semideciduous tree with a naturally scaly trunk that can grow from 4 to 9 m in height with thin, overhanging branches. It is a plant used for heterogeneous reforestation of preserved and protected areas and wood is also used in general carpentry and agricultural implements. The traditional use of the plant in cardiovascular disorders has been investigated (Wczassek et al., 2020), as well as its action potential as an antioxidant (Castelucci et al., 2020) and metabolic disorders (Donado-Pestana et al., 2015.

C. phaea -Co-occurrence network analysis by keywords
The analysis of the occurrence of keywords in the VOS, represented by Figure   Source: Authors.

Campomanesia lineatifolia Ruiz & Pav.
C. lineatifolia is an evergreen tree, which can grow from 5 to 10m in height. It is geographically distributed in the west range of South America, comprising the center and north of Brazil, Peru, Colombia and Ecuador. Its natural habitat is primary growth forests in non-flooded areas. Its fruits, harvested locally and consumed fresh or in the form of sweets, ice cream and jellies, are popularly known as "guabiraba" or "champa". From the leaves, volatile compounds used in the manufacture of perfumes are extracted (Canteiro & Lucas, 2019;The Plant List, 2013).

C. lineatifolia -Análises Bibliométricas
Bibliometric analyzes in WoS indicate that the most productive years were 2009, 2012 and 2010 with respectively 5, 4 and 3 publications. Brazil was the country that published the most, although in a less hegemonic way compared to other species (12/21 = 57.1%). Colombia, a country that is also home to this species, comes in second with 8 out of 21 publications (38.1%).

C. lineatifolia -Co-occurrence network analysis by keywords
The VOS analyzes in the Campomanesia lineatifolia species database, limited to 2 occurrences per word, out of 108 words, resulted in 19 items linked in a network, divided into 5 clusters, 77 links and 183 the total strength of the link. Figure 13 represents the network of keyword co-occurrence links, highlighting the terms Myrtaceae (which represents the family) linked to other species of the genus Campomanesia, xanthocarpa (8 occurrences, 12 links), adamantium (3 occurrences , 7 links) and sessiflora (2 occurrences, 6 links), suggesting that they were searched together. The term "essential oil" (9 occurrences, 16 links) linked to terms that denote chemical composition such as "beta triketones" (in lilac), "champane" and cryptomeridiol (in green), show the evolution of substances found in the composition of the oil. essential oil of the plant. The group of β-triketones, among which the champanones, the main constituent of the volatile compounds of Champa and one of the most responsible for the intense and pleasant odor, are rare structures in compounds of natural origin and can be found in other species of Myrtaceae, especially of the genus Eucalyptus, Kunzea and Leptospermum. Champanones A, B and C, are yellow pigments found in champseeds, to which antimicrobial, anthelmintic and insecticidal activities have been attributed. There are commercially synthetic β-triketones used as herbicide and due to the considerable presence of these compounds in C. lineatifolia, studies report a potential use of the species as an insect repellent (Bonilla et al., 2005;Osorio et al., 2006).   (Oliveira;Costa & Proença, 2020). It is popularly used in the treatment of liver disorders (Dorigoni et al., 2001) and diarrhea (Brandão, 1991).

C. guazumifolia -Análises Bibliométricas
The first study involving C. guazumifolia indexed in WoS, dated 2001 and investigated the chemical composition of the essential oil of some species of Campomanesia. In C. guazumifolia, the main constituents found were Spathulenol (27.7%) and 1β-caryophyllene oxide (29%) (Limberger et al., 2001). The second WoS publication came in 2013 and sought to understand the leaf and stem morphoanatomy of the species and indicated the presence of calcium oxalate and phenolic compounds in the leaves and also in the stem (Arruda et al., 2013). In 2018, there were 2 publications, one of which sought to morphologically characterize the development of fruits, seeds and seedlings, aiming at the commercial production of seedlings (Souza et al., 2018). The other study from 2018 investigated the anti-inflammatory activity and toxicological profile of the infusion of leaves in mice, in which anti-inflammatory potential with low toxicity was evidenced . In 2019, there were 3 publications. For the first time, antioxidant and antimicrobial potential of C. guazumifolia essential oil were reported and the main compounds identified by GCxGC/qMS were bicyclogermacrene (15%), globulol (5%) and spathulenol (5%). Sesquiterpene hydrocarbons (29 compounds) and oxygenated sesquiterpenes (20 compounds) were the most representative class of terpenes (Santos et al., 2019). Another 2019 study investigated the infestation of fruit fly species infesting C. guazumifolia fruits (Almeida et al., 2019). The third study from 2019 reported an increase in Sun Protection Factor (SPF) in formulations containing Octyl Methoxycinnamate in association with Campomanesia extracts (C. guazumifolia, C. sessiliflora, C. xanthocarpa and C. adamantium) alone or in association. All combinations were effective in increasing the SPF, and the combination of C.
xanthocarpa and C. adamantium obtained higher SPF rates (Catelan et al., 2019). Until October 2021, there were 3 publications and none of them with potential clinical application. One of them dealt with the morphoanatomical differences of parts of the ovary and pericarp of some species of Campomanesia native to Brazil (Pittarelli et al., 2021). Another study investigated the viability of this species and sought to elucidate aspects of pollen germination (Guollo et al., 2021) and the third proposed an alternative for the treatment of effluents in the pharmaceutical industry that produces ketoprofen, using acid-treated "setecapotes" tree bark sulfuric acid (Preigschadt et al., 2021).

C. guazumifolia -Co-occurrence network analysis by keywords
As there are only 10 publications about C. guazumifolia, all 87 words were considered for keyword co-occurrence analysis, which resulted in 72 items, 7 clusters, 436 links and 439 the total strength of the link. In Figure 14, which schematically presents these keyword co-occurrence relationships, it can be seen that in cluster 4, in dark blue, representing terms that appear in the first publications on the species, the words (e)-nerolidol, alpha-pinene, byciclogermacrene, globulol, linalool, spathulenol may indicate chemical composition studies. Terms indicative of biological activities such as "antioxidant activity", "solar protection factor", "cytotoxic activities" and "biological activity" in colors ranging from yellowish-green to yellow suggest research trends for these approaches. The xanthocarpa species appears in 2 occurrences, suggesting that they were investigated simultaneously.

Final Considerations
The analyzes of publications indexed in WoS, using bibliometric and scientometric mapping tools, suggest a growing interest in herbal medicines and medicinal plants native to Brazil with potential pharmacological applicability, without losing focus on sustainability and better use of our rich biodiversity, opening up thus a vast field of research that can investigate biological activities for species of the Campomanesia. New studies involving native Brazilian plants are welcome, so that they can both support their traditional use by communities and to open up new possibilities for identification and isolation of compounds for research on new drugs.