Global research trends of the studies on Murraya koenigii (L.) spreng: a Scopus-based comprehensive bibliometric investigation (1965–2023)

Murraya koenigii (L.) Spreng. has several well-established nutritional and therapeutic applications. Following our desire to investigate the global and scientific community's knowledge of medicinal plants, this study was intended to examine the evolution of knowledge related to M. Koenigii studies. The primary purpose of this paper is to clarify the status of these studies, investigate their methods, findings, and trends, and define their significance within the current research landscape. To achieve these goals, bibliometric analysis was conducted, retrieving, and analyzing 934 original articles published between 1965 and 2023 based on Scopus Dataset results. Data were exported as CVS (comma-separated values) and BibTex files and analyzed using Bibliometrix and VOSviewer software. Articles from 502 sources have been identified, averaging 21.8 citations per document. The research in this plant has had exponential growth (R2 = 0.77). International co-authorship is 13.08%. India and Malaysia are the top publishing countries. Debajo, A.C. (Nigeria), Phatak,R.S. (India), and Sukari,M.A. (Malaysia) are the most productive authors. The top source is the Journal of Ethnopharmacology. "Green synthesis," "nanoparticles," "oxidative stress," "Asian citrus psyllid," "apoptosis," "antimicrobial," "anticancer," "Chromatographic profile," "bioactive compounds," and "alkaloids" are strongly related to the current trends in M. Koenigii research. Regarding the specialized topics, M. Koenigii's study concentrated on using this plant as an antioxidant agent in manufacturing and biological systems. Dynamic subjects like chromatographic profiles, essential oils, and Asian citrus psyllids were included in the motor theme. The current study used bibliometric techniques to evaluate research on M. Koenigii and identify trends and potential future research hot spots.

Following our interest in exploring the global and scientific community's knowledge of medicinal plants, this paper provides an overview of the knowledge regarding the mechanisms of action and the essential bioactive components present in this plant.This work is also susceptible to the influence of the knowledge produced, its size, and its global dissemination.It also provides a real-time platform for all those interested in traditional medicine to learn about the parties working in this field to facilitate future scientific collaboration.To accomplish this, we utilized bibliometric methods to unearth our intent.Where no such reference is available for this tree.According to our knowledge, this paper is the first to conduct a bibliometric analysis of knowledge and research on this tree.

Database, data acquisition, and querying
The bibliometric study was carried out with the assistance of the Scopus database as a primary source.Scopus is a platform owned by Elsevier and comprises a sizable collection of bibliographic databases, citations, and references from scientific publications in any field of knowledge, including science, technology, social sciences, arts, and humanities (Al-Khoury et al. 2022).Scopus can be accessed through the Elsevier website.The search terms are related to "Murraya koenigii" (title, abstract, or keywords).The study's time frame was 1965-2023.The data were extracted on June 13, 2023.There were only journal articles present.The languages of the documents published are limited to English only.Conference proceedings, articles, books, etc., were also excluded.The procedure flow used to gather data and conduct queries are shown in Fig. 1.

Data filtering and sample size
From 1965 to 2024, 1091 M. Koenigii-related works were retrieved from the Scopus database.The researchers identified and analyzed 934 original articles.The final publication date for these papers is 2023.Therefore, all papers published after this date were excluded from the current study.The inclusion of these works in the present research, despite belonging to the same period defined in the search term, may distort the interpretation of the data, and the growth of the analysis because they belong to something other than the calendar year of the period under review.According to the guidelines for bibliometric investigations, any sample size greater than 200 research documents is sufficient to execute a reliable study (Rogers et al. 2020).The final data were exported from the Scopus database as two file types, CVS and Bib format.

Analysis tools: bibliometrix and vosviewer
Open-source tools for quantitative scientometric and bibliometric research that cover all the major bibliometric methods of analyses include Bibliometrix (R Package) and Vosviewer (Oladinrin et al. 2023).These tools enable researchers to study and visualize the various research cooperation networks established or developing patterns in a particular field of knowledge, as well as to highlight the most pertinent documents, journals, nations, authors, and institutions.Bibliometrix (R Package) and Vosviewer have been used in a number of studies.Research in the areas of biology, artificial intelligence (Hou and Yu 2023), Pharmacology (Abdelwahab et al. 2023;Ge et al. 2022;Li et al. 2022;Wang et al. 2022), and social research (Hou and Yu 2023) and data science (Nobanee 2021) are a few examples.

Main information about the collection
The main findings of the analysis-document type, document content, and author collaboration-are presented in Table 1.With 934 documents total and an average of 21.8 citations per document, the study covers the years 1965 to 2023.The study has shown that articles in 502 scientific sources.Only 2532 of the

Country, affiliation, and author scientific production
Figure 2 shows the distribution of scientific production frequencies worldwide by the affiliation country.A total of 66 countries have contributed to the publication of journal articles on M. Koenigii-related works.Within the top 5, we appreciate how India in 1 st position (1167 freq.) and the Malaysia in 2nd position (192 freq.)stands out on the hegemony of academic-scientific production, followed in the 3rd position by the USA (60 freq.), in 4 th position Pakistan (58 freq.) and 5th position China (53 freq.).Universiti Putra Malaysia, Universiti Teknologi MARA, (Malaysia), Bose Institute, University of Calcutta, Central Drug Research Institute (India) had the highest number of published articles on M. Koenigii.Debajo, A.C. (Obafemi Awolowo University, Nigeria), Phatak, R.S. (Deemed University, India), and Sukari, M.A. (Universiti Putra Malaysia, Malaysia) are the highest productive authors with nine documents for each.

Three field plot
Observing the trends in the study topics, countries, and states of M. Koenigii publications in addition to the annual production is crucial.Author keywords are in the center of Fig. 4, authors are on the right, and countries  Koenigii is planted.When examining the authors' keywords, we find that India has participated in all the research on this plant, as this is evident from the flow we notice in Fig. 4. As for some countries, such as the United Kingdom, their research was limited to a narrow range.Many researchers have studied leaves' biological and chemical properties, such as antioxidant activities, anticancer properties, green synthesis, antibacterial activity, essential oil, and anti-diabetic properties.
Table 2 displays the top 20 journals in which the most papers on M. Koenigii were published.The total number of sources is 502.A total number of 934 articles regarding M. Koenigii were published in these journals between 1965 and 2023 and indexed in the Scopus database.The top four journals were the Journal of Ethnopharmacology (22 papers), International Journal Of Pharma And Bio-Sciences (18 documents), Phytochemistry (14 documents), and Asian Journal Of Chemistry (12 documents).Although the Journal of Ethnopharmacology has the highest number of citations, Food Chemistry and the Journal Of Agricultural And Food Chemistry have the highest average of citations.This means that the research published in these two journals has a more cognitive impact than those published in the first.

Trendy topics
Trendy topics have evolved over the last 60 years, as shown in Fig. 5.The analysis of trendy topics was performed in Bibliometrix applications using keywords.Keywords such as "green synthesis," "nanoparticles," "oxidative stress," "anti-diabetic," "Asian citrus psyllid," "apoptosis," "antimicrobial," "anticancer," "HPLC," "bioactive compounds," "phytochemicals," and "alkaloids" are strongly related to the current trends in M. Koenigii research.The term frequency is shown in blue circles (Fig. 5), and the time span of the keyword is shown in the horizontal line.The term "Rutaceae" has the most extended shelf life.

Thematic map
The thematic map divides the majority of topics into two groups: motor themes and fundamental themes, both of which have a high centrality but a low density.The basic and motor topics have a lot of potential, and researchers can successfully pursue them.The specialized and motor themes' topics are frequently covered in great detail in the M. Koenigii literature.Though they have been examined, the worries in the case of M. Koenigii have not fully developed.Due to the research that has been done and the requirement for more effort, this problem is moving from emergent to basic.The phrase "Huanglongbing (yellow dragon disease)," which is both an emerging subject and one of the core ideas, is one such example.Therefore, there is a clear need for more research.Figure 6 depicts where the themes are located.These themes are generated through clustering.A bibliometric analysis and enrichment method is clustering.Its main objective is to organize network clusters into topic clusters, track

Table 2 Top publishing sources according to Scopus database
The sources were chosen based on the fact that they contain the largest number of documents related to the curry tree CA: citation average or the average number of citation per year

Social analysis: co-authorship analysis
VOSviewer was used to assess the collaborative research globally.A total of 66 countries have contributed to the publication of journal articles on M. Koenigii-related works.Six clusters were mapped for 23 countries, which met the criteria of minimum number 5 documents (Fig. 9).India possessed the largest node in the red cluster with Total Link Strength of 52.Indian institutions collaborated significantly with Bangladesh, Pakistan, China, Australia, Canada, and Spain.Four countries formed the green cluster with Malaysia as the strongest collaborator.Germany, United States, UK, Saudi Arabia are the top collaborators in the blue, yellow, purple clusters, respectively.Biblioshiny parameters for author's collocation are shown in Table 1.

Impactful research: citation analysis
The total number of citations for all 934 is 20,366, with an H-index of 68 (Fig. 8).The H-index of 68 is marked by the yellow star (Fig. 10).

Discussion
This paper examines studies' status, issues, methodologies, findings, and trends, as well as their relevance to current research related to M. Koenigii.Using Scopus Database findings, bibliometric analysis was performed on 934 publications published between 1965 and 2023.
It has not been established in any of the previously conducted study that this plant, which is notable for its beneficial effects on both nutrition and health, has been the subject of any bibliometric investigations into the dynamics of existing knowledge or the identification of potential research topics.
The curry tree, also known as M. Koenigii or Bergera koenigii, is a species of tree that is endemic to Asia and may be found growing in both tropical and subtropical climates.The highest amount of articles devoted to studying this plant has come out of Asia, specifically from countries like India and Malaysia.This could be due to the fact that the tree originated in these nations, its widespread usage in medicine and cooking, and the fact that   4 The most cited documents * Benalla et al. (2010), Devatha et al. (2016), Huda-Faujan et al. (2009), Philip et al. (2011), Quraishi et al. (2010), Ramsewak et al. (1999a), Rehana et al. (2017), Srinivasan et al. (2001), Tachibana et al. (2001) and Wong et al. (2006)  these countries make use of the collected research experience.Research in nations outside of Asia, including Nigeria, the United States, and the United Kingdom, has also demonstrated the plant's significance.Adebajo, A.C., a Nigerian researcher, accumulated a substantial body of knowledge about the curry tree.The biochemical, pharmacological, phytochemical, and toxicological activities of crude extract and some alkaloids obtained from the leaves of M. Koenigii grown in Nigeria were studied by him and his team from the Department of Pharmacognosy, Faculty of Pharmacy, Obafemi Awolowo University, Nigeria (Adebajo et al. 2006(Adebajo et al. , 2009(Adebajo et al. , 2014;;Adebajo and Reisch 2000;Reisch et al. 1994).
The top journal in the dissemination of M. Koenigii research is the Journal of Ethnopharmacology.Nearly all of this plant's parts are used in Ayurveda, the Indian system of traditional medicine, to cure a wide range of ailments.The plant's new leaves, fruits, bark, and roots are among these components.Green curry leaves were commonly used in traditional medicine to treat piles, inflammation, itching, new cuts, diarrhea, and edema.While the roots were traditionally used to cure generalized pain, the bark proved useful for healing snakebites (Adebajo et al. 2009;Jain et al. 2017;Tan et al. 2022).About 30% of the papers published in the journal were ethnobotanical studies on this tree (Aniqa et al. 2022;Bhupatiraju et al. 2023;Husna et al. 2018;Kamsani et al. 2020;Mondal et al. 2022b;Singh et al. 2023).At the same time, the remaining number (16/22) reviewed experimental studies on many biological properties of this plant.Food Chemistry is the most impactful journal in M. Koenigii research as demonstrated in Table 2 with citation average of 115.82.This journal accommodated various articles on the antioxidant properties of this plant (Biswas et al. 2012;Choudhury and Garg 2007;Ningappa et al. 2008;Raju et al. 2007;Rao et al. 2007;Wong et al. 2006).It is generally known that consuming more vegetables and medicinal herbs along with antioxidants lowers the chance of developing certain ailments (Zahin et al. 2013).The dietary use of this plant may explain the research interest in its antioxidant properties and the intensity of studies on this property.
Trendy topics have evolved over the last 60 years, as shown in Fig. 5. Publication keywords are frequently employed to expose the knowledge structure of study domains and are regarded as the fundamental components of conveying knowledge concepts in bibliometric research.Research topic analysis based on co-word clustering, knowledge mapping based on co-word networks, and hotspot discovery and trend analysis based on keyword frequency analysis are all covered in related studies (Aniqa et al. 2022;Bhupatiraju et al. 2023;Husna et al. 2018;Mondal et al. 2022b;Singh et al. 2023).The latest trending topics in M. Koenigii research are green synthesis and nanoparticles.In the field of phytochemistry, biogenetically manufacturing nanoparticles from plant derivatives and exploring their potential for usage as novel therapeutics has been one of the hot research issues.The focus of current research on nanoparticles is the range of applications for green synthesis (Shreyash et al. 2021).In recent studies, green chemistry was used to synthesize zinc oxide nanoparticles using zinc nitrate and the bioactive ingredients in M. Koenigii leaf extract (Lakshmikandhan 2020;Qais et al. 2019).One of the important topics that will shape future research on this tree is green synthesis.This can be linked to the fact that this tree began to enter other environmental ranges and leave its original habitat.The tree is tropical or subtropical and indigenous to Bangladesh, India, and Pakistan.More recently, in Australia, commercial plantations have been built.It is grown throughout tropical Africa in nations like Nigeria, Kenya, Tanzania, and the majority of the islands in the Indian Ocean, where Indian immigrants landed (Adebajo et al. 2006(Adebajo et al. , 2009(Adebajo et al. , 2014(Adebajo et al. , 2004;;Adebajo and Reisch 2000;Balakrishnan et al. 2020;Nazeer et al. 2022;Panda 2014;Sharma et al. 2013).
In this study, we used bibliometric analysis to explore the intellectual structure of M. Koenigii literature.The majority of topics are divided into two groups on the thematic map: motor themes and fundamental themes, both of which have a high centrality but low density.Basic and motor topics have great potential, and researchers can pursue them successfully.In the literature on M. Koenigii, the specialized and motor themes are frequently and thoroughly discussed.Fourteen clusters were generated using author's keywords.These clusters were divided into four themes to represent the intellectual structure of M. Koenigii literature.Knowing the knowledge structure of any research field helps researchers and decision-makers shape the future and current map for this research field and save effort and money (Karakose et al. 2022).Global evaluation of the collaborative research was done using VOSviewer.Significant collaboration took place between Indian institutions and Bangladesh, Pakistan, China, Australia, Canada, and Spain.Phytochemistry is a multi-and inter-disciplinary field of study that focuses on the chemical compounds produced by plants, particularly secondary metabolites, as well as their structural formulations, biosynthetic pathways, functions, mechanisms of action, and applications.Historically, bibliometric techniques were used to quantitatively obtain a structural overview of research collaboration (Wilson 2022).
Measuring scientific output is a more involved and consequential task than at first glance.Many other approaches have been offered for quantitative analysis, but none of them are without flaws.Analysis of the frequency with which a given article, author, or institution is mentioned by other works or writers is known as a "citation analysis" (Cariveau et al. 2020).According to the established definition, an author or journal with a high h-index is characterized by having published a minimum number of works that have received an equal or greater number of citations.The h-index is not a complicated concept to understand.Simply plot the number of papers published against the number of citations received, and the h-index is the point at which the 45-degree line (citations = papers) intersects the curve.The h-index is useful because it provides a single metric that takes into account both productivity (the number of papers published) and impact (the number of citations).Therefore, a high h-index requires both production and impact; having either a small number of highly cited publications or a large number of papers with few (or no) citations will not provide a high h-index (Bertran et al. 2020).20,366 citations and 68 H-indexes for all 934 (Fig. 8).Yellow stars indicate 68 H-index.Table 4 shows the 1965-2023 M. Koenigii research papers with the most citations, journals, and citation averages."Antioxidant Activities of Aqueous Extracts of Selected Plants" has the most citations (621) and average (36.53).It was discovered that the leaves of M. Koenigii exhibit the highest levels of antioxidant activity as well as total phenolic content (Bhupatiraju et al. 2023;Mondal et al. 2022b;Nazeer et al. 2022;Singh et al. 2023).

Limitations
This study, which offered thorough data on the intellectual development, influence of knowledge, and performance of M. Koenigii literature, had certain drawbacks.First off, our data set only included Scopus-indexed journal articles; it did not include books or book chapters, dissertations, or conference proceedings.Despite Scopus' extensive coverage of high-impact journals, our study may have unintentionally left out certain crucial studies.Second, as implied by its methodology, the study is distinct from conventional review studies.As a result, the results do not correspond to those of earlier studies but rather demonstrate the bibliometric and evolutionary characteristics of the literature on M. Koenigii in accordance with the study of meta-data related to these studies.
Our study still has the potential to lay the groundwork for upcoming analyses and investigations into M. Koenigii by defining the thematic progression of the subject field.

Conclusions
The current study employed a broad investigation into the scientific evolution of M. Koenigii research field, and exhibited the intellectual and conceptual architecture of the knowledge related to this plant established during the last six decades.Despite the fact that the methodology used in this study establishes the value of this tree from a medicinal and dietary standpoint, it also creates a crucial framework for future investigations in the search for novel pharmacological values, particularly by highlighting the primary research topics and encouraging the continuation of research in the areas under investigation.A major implication of the current study is that, despite the breadth and extent of research on this tree, it is promising as a comparative source for many botanical studies.Based on this result, we believe that research in this field is still in its infancy, although the distributed perspective has made great inroads in medicinal plant research.The study spans the years 1965 through 2023, with a total of 934 documents and an average of 21.8 citations per document.India and Malaysia are the top-publishing countries.Debajo, A.C. (Nigeria), Phatak, R.S. (India), and Sukari, M.A. (Malaysia) are the highest productive authors.The top source is the Journal of Ethnopharmacology.Regarding the specialized topics, M. Koenigii's study concentrated on using this plant as an antioxidant agent in manufacturing and biological systems.Dynamic subjects like HPLC profile, essential oil, and Asian citrus psyllid were included in the motor theme.In conclusion, filling these study gaps in this plant research would make a significant contribution to our optimal exploitation of it in terms of health and nutrition.Additionally, it would advance the knowledge base to a more mature stage, which can also be examined in future scientific mapping studies.

Limitations
There are certain limitations to the present research.Even though the author tried his utmost to minimize this sort of inaccuracy, false-positive and false-negative outcomes are possible.Furthermore, the use of Scopus to retrieve documents may have resulted in the loss of certain papers published in non-English nations' natively unindexed journals.The proportion of papers connected to M. Koenigii that focused on non-English studies was 0.22%.

Fig. 1
Fig. 1 Data search strategy in the Scopus database.ar: article; PUBYEAR: publication year; DOCTYPE: type of the document

Fig. 2
Fig. 2 Country production.The map illustrates the scientific productivity attributed to the plant under investigation in the research.The aforementioned figure was generated with the Bibliometrix program.There exists a positive correlation between the intensity of the blue hue and the level of scientific productivity

Fig. 3 Fig. 4
Fig. 3 Annual scientific production related to M. Koenigii.The figure was generated using MS-Excel (n = 934).The data were extracted on June 13, 2023

Fig. 5
Fig. 5 Trending topics.The figure was generated using biblioshiny application in Bibliometrix and BibTex data format (n = 934).Blue circles denote the term frequency, and a horizontal line displays the term's time range.The phrase "Rutaceae" has the longest expiration date Figure 8 was generated by utilizing the VOSviewer program for the years 2015 through 2023 for the purpose of delving more into the dynamics of knowledge and locating research subjects that have surfaced more lately.According to the indicator that is located next to Fig. 8, recently discussed subjects include programmed cell death and green synthesis.

Fig. 7 Fig. 8
Fig. 7 Thematic evolution.The figure was generated using biblioshiny application in Bibliometrix and Bib data format (n = 934).Bigger boxes show the strength of the terms.The lines represent the intellectual correspondence link between the terms

Fig. 9
Fig. 9 International collaboration.VOSviewer mapping of the top 23 documents with more than five documents was performed.The shapes represent the number of documents.The lines represent the collaboration link between the countries.Countries with the same color had more collaboration among them

Fig. 10
Fig. 10 Citation score (H-index = 68).Figure was generated using Scopus Analytics feature.High h-index is characterized by having published a minimum number of works that have received an equal or greater number of citations

Table 1
Main information The topic development of M. Koenigii literature since 1965 is seen in Fig.7.Using the author's keywords, the thematic progression demonstrates the development of topics through time.One-time breaks lead to two-time segments, and "biblioshiny" is used to develop thematically.To preserve a more realistic image of the issue's progression, the researcher's judgment will choose how to divide the time period.The first section covers the years 1965 through 2014 and the second, 2015 through 2023.Over time, themes developed.The primary focus of M. Koenigii research has always been ethnopharmacological findings.Analysis shows that from 1965 to 2014, the studies began to include medicinal properties of the plant and it's pure compounds including anti-inflammatory, antioxidant, antifungal, antinociception, and ethnobotanical studies.As a result, research on M. Koenigii shows an increasing tendency until 2022.From 2015 forward, the research on this tropical tree has advanced dramatically.The topics were more versatile.Researchers have explored new areas such as pure compound isolation, phytochemical screening, identity of curry leaves as spice, green chemistry, spray drying, biological activities of girinimbine, and mahanine, and mild steel.

Table 3
Clustering of thematic structure* *This table is linked to Fig.6, which presents the terms used by the program to build each cluster.The cluster was named by giving it the name of the most frequent word in that cluster **The clustering was conducted using biblioshiny application in Bibliometrix and Bib data format (n = 934)