Schinus terebinthifolius Raddi: Scientometric Analysis Schinus terebinthifolius Raddi: Análise Cientométrica Schinus terebinthifolius Raddi: Análisis Cienciométrico

Schinus terebinthifolius (Anacardiaceae) is among the medicinal species native to Brazil, known as mastic-red and mastic-pepper, whose stem bark is used to fight inflammation of various origins, as it has anti-inflammatory and healing properties. The objective of this study is to explore trends in the publications portrayed on the species S. terebinthifolius, analyzing axes such as time, countries, journals, impact factors and citations, the scientometric approach was used to summarize all the studies on S. terebinthifolius in a single article. 475 publications were used with an average number of 20.8 publications per year, encompassing 68 research areas and published in 220 different journals, covering all retractions visible on the Web of Science from 2001 until May 2021. The most productive country was Brazil with 271 articles, followed by the USA with 105 articles. The methods and results of this study can be applied to continually understand the nature of research on the species.


Introduction
The species of the Anacardiaceae family are marked by having great economic importance in the supply of edible fruits, useful woods or ornamental species (Wheeler et al., 2016), and are known to contain a great diversity of attractive biomolecules (Feriani et al., 2021). The healing potential of many medicinal species is due to the bioactive compounds produced by the secondary metabolism of these plants (Zotti-Sperotto et al., 2021). Several species of medicinal plants are popularly used to combat different types of diseases. However, since they are products that have not yet been studied, medicinal plants need a lot of research, which has provided important advances in the treatment of various pathologies (Azevedo et al., 2015).
Schinus terebinthifolius Raddi, is one of the new potent botanical agents in the prevention and treatment of chronic diseases (Feriani et al., 2021), it has been used as a remedy for ulcers, respiratory problems, wounds, rheumatism, gout, tumors, diarrhea, skin ailments, arthritis, antiseptic, balsamic, haemostatic, anti-inflammatory and antimicrobial. Also, the decoction of flowers, stalks, fruits and leaves are used for the treatment of tumors and lepra (Lima et al., 2009;Santana et al., 2012;Tlili et al., 2018). Its biological applications have been described since the first edition of the Brazilian Pharmacopoeia, published in 1926. Is known as "pimenta-rosa", "aroeira-vermelha", "aroeira-pimenteira", "aroeira-da-praia", "aroeira-negra" and/or "aroeira-de-minas" (Silva et al., 2017), mainly for the appearance of its fruits and for being used as a food flavoring. In addition to its medicinal properties, this vegetable is commonly used in the afforestation of streets and squares and in the production of firewood and charcoal (Azevedo et al., 2015).
The species, which has a tropical and subtropical distribution, is native to South America, encompassing Brazil, Paraguay, Uruguay and eastern Argentina. and can be found in Europe, where it is cultivated as an ornamental species, Central and South America, mainly in Florida, where it has an invasive behavior. It is widely distributed throughout the Brazilian territory, extending from Pernambuco to Rio Grande do Sul (Wheeler et al., 2016). Due to the ease of adaptation to different habitats, the species can survive in dry seasons, it is easily seen throughout the coast of Brazil, but also in dry lands, inhabiting various plant formations.
In the Florida Everglades ecosystem, Brazilian Peppertree is the most widely distributed and abundant invasive weed, occupying 30,379 ha-an area greater than the combined infestations of the next 3 most-problematic plant species. The US Fish and Wildlife Service (1998) identified Brazilian Peppertree as one of the most significant nonindigenous species currently impacting federally listed threatened and endangered native plants throughout the Hawaiian Islands. Initial surveys to search for potential biological control agents for Brazilian Peppertree were conducted in northern Argentina and Brazil in the 1950s and early 1960s. Classical biological control may provide an ecologically sound, cost-effective, and sustainable component of management strategies to protect native plants in these habitats (Wheeler et al., 2016).
The objective of the present work, therefore, was to carry out a scientometric analysis of publications on the species S. terebinthifolius, in the Web of Science database, to evaluate the development of scientific researches with the species published so far. Thus, the number of articles published on the subject, authors, journals, countries, institutions, citations and co-citations, the most identified words in the main research areas addressed, was quantified. After data collection, the VOSviewer software was used to generate, visualize and analyze bibliometric networks. It is hoped that the results of this research will provide researchers and practitioners with a comprehensive understanding of the status quo, trend research and promote further study in this field.

Database collection
One of the decisions to make in undertaking an analysis of a knowledge domain such as in this study is for the researcher(s) to identify scientific databases to use. The primary sources of databases were The Clarivate Analytics Web of Science (WoS) . The WoS has been widely recognized as an important database by the international scientific community (Castro et al., 2021) and covers journals, and being able to exclude articles of conference proceedings, meeting abstracts, editorial materials, and reviews. The database was used to search for scientific studies on Schinus terebinthifolius (updated in May 2021). The keywords "Schinus" AND "terebinthifolius" for the topic search, showing results since 1977, we restrict the search of the information on period 2001 to 2021, and we exclude articles of conference proceedings, meeting abstracts, editorial materials, and reviews ( Figure 1).

Data analysis
Scientometrics is defined as the quantitative study of science (Kim & Chen, 2015), is a technique that allows for a broader yet concise capturing and mapping of a scientific knowledge area by identifying structural patterns and tracing salient research frontiers using mathematical formulae and visualization . The scientometric analysis is a technology that demonstrates the scientific development process and structure relationship based on the knowledge domain (Si et al., 2019). For scientometric analysis, this study used VOSviewer, which is a software tool designed for constructing and viewing bibliometric maps, networks with journals, researchers, or individual publications as authors, and based on co-citation, bibliographic coupling, or co-authorship relations, useful for displaying large bibliometric maps in an easy-to-interpret way.
Once the data is obtained, the analysis develops a performance analysis process (

Results and Discussion
This section discusses the facets and results of the scientometric analysis of this study, as described in the research project. The study digitized journal article titles and abstracts to identify valuable articles in the researched field.

Articles Published
This procedure collected a total of 475 articles in different journals classified in all WoS categories. To limit the range of articles, this study selected only 416 journal articles that met all the criteria, omitting 41 articles from conference proceedings, meeting abstracts, editorial materials, and reviews. These articles were cited 5527 times cited in article publications as references. From 2001 to 2021, the distribution of annual publications is shown in Figure 2. Source: Authors.
The first article on S. terebinthifolius was in 1977 with a focus on terpenes registered in the plant (Lloyd, 1977), between 1997 and 2007 less than 10 articles were published each year, revealing that this field of research was in a preliminary stage. In general, the results have been increasing continuously for almost 20 years, the number of articles increased after 2007, maintaining the average number of 20.8 publications per year, which has not reached a high level, suggesting that this field still needs attention and advances important. The trend line follows the exponential distribution, showing slow growth during the early years and more growth in later years. In 2021, only 11 articles were found, however, as we are in May, the expectation is to reach the same number or more publications as the trend line is projected. In general, even though the year 2021 shows a dip, the annual publication trend follows an increasing trend.

Research area/and journals
The research areas discussed in this section refer to the most cited research areas and journals of S. terebinthifolius as defined by WoS. The 416 articles were categorized into 68 research areas and ( Figure 3) and the articles selected published in 220 different journals. Source: Authors. Figure 3 shows the most common research area was Agriculture, and 57 articles were categorized in this area, which is equivalent to 13.6% of the total number of articles. Interestingly, two other areas have the same frequency as Plant Sciences and Environmental Science Ecology, with 56 articles (13.3%) and 55 articles (13.1%) respectively. The next most was Entomology with 53 articles (12.9%), Forestry and Pharmacology Pharmacy both with 47 articles (11.2%), Chemistry with 42 articles (10%). The last three most common areas in the study are Molecular Biochemistry, Food Science Technology, Biotechnology Applied Microbiology all with less than six percent and other distinct areas with 117 articles, which all these areas indicated is the diversity of this research field.
The top 20 journals accounted for approximately 65% of the 416 publications. The top 5 most productive journals that have published at least 10 articles of S. terebinthifolius from 2001 to 2021 on Table 1. Source: Authors. Table 1 represents the most productive journals, Brazilian Journal of Pharmacognosy were tied for first place (13 articles followed by Biocontrol Science and Technology (11 articles), Biological Invasions (11 articles) and Ciência Rural and Revista Árvore both with 10 articles. These top three journals accounted for 13% of the total articles, which might indicate that they were the most influential publications in the field for the past twenty years. As can be seen from the research area and journal list, the study of S. terebinthifolius involves multiple disciplines. The table also shows the number of citations and total link strength of each journal.

Countries/regions and institutions contributions
According

Authors contribution
The 416 publications shortlisted from the WoS database involve contributions from 1704 authors and coauthors. The contribution of the individual author and collaborative authors has been analyzed in this domain, the five most productive authors are described below (Table 2).

Articles more citated
The most-cited articles on the topic of S. terebinthifolius since 2001 were summarized in Table 3 with 10 most cited articles, including total citations, year published as well as a research direction. It should be pointed out that the research directions were not necessarily mutually exclusive.

Network analysis 4.1 Document co-citation network
Co-citation analysis of bibliographic elements contained in the scientific literature can be applied to explore the knowledge structure and dynamic evolution of a specific research area. Co-citation analysis was a useful method to map how subject specialties of scientific research and to study how differences in research between sets of publications. (Wei & Zang, 2020   Source: Authors. Figure 5 represents the 127 main documents co-cited articles in the reference or bibliography of selected articles with a limit of 15 citations per document. In the co-citation map, fifteen well-defined clusters are observed. The co-citation network shows a network of references that have been co-cited by a number of publications. Each node represents a cited reference, and the borders denote the co-cited relationships between articles (Wei & Zhang, 2020). VOSviewer colors groups of citations using a set of colors selected from the menu on the right. The largest clusters are colored dark red for the largest, green for the second largest, dark blue for the third largest, and yellow for the fourth largest cluster (Williams, 2020). Highly cited articles are indicated by the larger size of the bubble (Lazar & Chithra, 2021).

Co-citation authors
A co-citation link is built by the authors who are citing the articles ( Figure 5). Once two articles are cited together in another article results in the co-citation of the two articles, say, in this case, authors, documents, or journals are cited by a journal article and described as a "proximity measure" for the items (Lazar & Chithra 2021;. Co-citation analysis of authors offered a new technique that could contribute to understanding the intellectual structure of the sciences (Wei & Zhang, 2020). A visualization of the 215 authors e 4 clusters and their citation relations is provided in Figure 6. In the co-citation analysis, Figure 6, seven well-defined clusters are observed. VOSviewer colors clusters of citations using a set of colors selected using the menu on the right hand side. The largest clusters are colored with a dark red for the largest, green for the second largest, a dark blue for the third largest and yellow for the fourth largest cluster (Williams, 2020).
In this visualization, the size of a cluster reflects the number of publications belonging to the cluster. Larger clusters include more publications. The distance between two clusters approximately indicates the relatedness of the clusters in terms of citations. Clusters that are located close to each other tend to be strongly related in terms of citations, while clusters that are located further away from each other tend to be less strongly related. The curved lines between the clusters also reflect the relatedness of clusters, with the thickness of a line representing the number of citations between two clusters (Van Eck and Waltman, 2010).

Analysis de co-words
The mapping of the most used keywords and terms helps researchers to define the types of research in their searches and studies (Van Eck & Waltman, 2010). This analysis supports research to select the correct search terms, we identified the 41 keywords with a minimum threshold of 8 occurrences each is shown in Figure 7.  Analyzing the clusters, we observe that the words used in each cluster are linked to a specific area of research. The grouping of the red cluster is formed by words linked to biological control, the growth of Brazilian pepper in Florida. The green cluster group is formed by words linked to the biological activities and chemical composition of the extract and essential oil. The blue cluster grouping is linked to the study of plant toxicity.

Conclusion
In this study, we have performed a comprehensive study of the worldwide scientific output of Schinus terebinthifolius Raddi research from 2001 to May 2021. showing that scientific production on the species has been growing, thus standing out the importance of the subject. This scientometric study provides an in-depth analysis of the species' global survey, highlighting the multidisciplinary nature. Over the past two decades, research has progressed enormously, resulting in a better understanding in the areas of agriculture, plant studies, ecology, chemistry and pharmacology.
National and international collaboration plays an important role in research in this area. Greater international cooperation could help in the study and concentration of research activities in countries with more developed scientific systems, such as Brazil or the United States, and increase knowledge reaching more areas of less explored research. With regard to this, the objective of the current research work was to collect, record, and illustrate the possibility and extent of the current research and serve as a source for future consultations on the topic, identifying the most recent research trends that could help significantly the increase the traditional literature reviews and provide helpful information to determine new research directions and perspectives.