Research Article | Open Access
A Comparative Analysis of Ethnomedicinal Practices for Treating Gastrointestinal Disorders Used by Communities Living in Three National Parks (Korea)
The purpose of this study is to comparatively analyze the ethnomedicinal practices on gastrointestinal disorders within communities in Jirisan National Park, Gayasan National Park, and Hallasan National Park of Korea. Data was collected through participant observations and indepth interviews with semistructured questionnaires. Methods for comparative analysis were accomplished using the informant consensus factor, fidelity level, and internetwork analysis. A total of 490 ethnomedicinal practices recorded from the communities were classified into 110 families, 176 genera, and 220 species that included plants, animals, fungi, and alga. The informant consensus factor values in the disorder categories were enteritis, and gastralgia (1.0), followed by indigestion (0.94), constipation (0.93), and abdominal pain and gastroenteric trouble (0.92). In terms of fidelity levels, 71 plant species showed fidelity levels of 100%. The internetwork analysis between disorders and all medicinal species are grouped in the center by the four categories of indigestion, diarrhea, abdominal pain, and gastroenteric trouble, respectively. Regarding the research method of this study, the comparative analysis methods will contribute to the availability of orally transmitted ethnomedicinal knowledge. Among the methods of analysis, the use of internetwork analysis as a tool for analysis in this study provides imperative internetwork maps between gastrointestinal disorders and medicinal species.
After the agreement of the Nagoya Protocol, which has highlighted the importance of traditional knowledge of local communities, interest has grown stronger regarding ethnomedicinal knowledge in the world . Ethnomedicinal knowledge plays an extremely vital role in the health care systems of developing countries and is utilized as an alternative for the treatment of disorders without side effects in developed countries . Investigations regarding ethnomedicinal knowledge in local communities have often been conducted to the indigenous communities of Asia, Africa, and South America.
At present, studies on the ethnomedicinal practices of local communities to treat specific disorders have been accomplished, including liver disease [3, 4], birth-related diseases [5, 6], uremia , diabetes , psychiatric disorders , ophthalmology , skin disorders , stomach issues , veterinary medicine [12, 13], and other health conditions. However, research using INA on the ethnomedicinal practices to treat gastrointestinal disorders within local communities has yet to be accomplished.
Investigations for the ethnomedicinal practices of local communities to treat specific disorders in Korea have included respiratory diseases , digestive system disorders , and pain relief  for communities in North Jeolla Province.
National parks in Korea are areas designated to protect the representative ecosystem and the natural/cultural sceneries by the Ministry of Environment and are defined as natural areas of both land and sea. National parks are managed directly by the government and their purpose is to combine both a conservation and a sustainable use of the natural resources within the parks.
Designated as the first national park in 1967, Jirisan National Park spreads across one city and four counties and lies within three provinces. The total area of Jirisan National Park is 485 km2, which makes it the largest mountainous national park in Korea.
Hallasan National Park is located at the heart of Jeju Island, the largest and most beautiful island in Korea. Its total area is 1,849.18 km2 and is located at the southernmost tip of the nation.
Located in the deep inlands of southeastern Korea, Gayasan National Park spreads across one city and four counties and is located within two provinces. The total area of the park is 76.256 km2 and is known as the sacred site of Buddhism.
Accordingly, this research is the first attempt for comparing and analyzing ethnomedicinal practices to treat gastrointestinal disorders of communities in three national parks in Korea. However, up until now, a quantitative analysis for ethnomedicinal knowledge of local communities has relied solely on the consensus of its informants [17, 18] and the recorded fidelity levels [19–21].
These methods have limitations on the sufficient interpretation of ethnomedicinal knowledge as a complicated knowledge system embedded within the traditional ethnographical properties. Therefore, a deeper analysis of ethnomedicinal practices in treating specific disorders within the local communities is necessary for obtaining more specific details regarding the internetwork analysis (INA) between disorders and medicinal species.
This research suggests that the applications gained from utilizing the comparative INA for ethnomedicinal practices on gastrointestinal disorders within communities in three national parks will result in further research incorporating INA. The three study areas included in this study are Jirisan National Park (JNP), Gayasan National Park (GNP), and Hallasan National Park (HNP). These regions are included as typical inland and island areas of the southern region in Korea. Among the three national parks, the ethnomedicinal practices of the communities living within HNP were investigated in regard to both medicinal plants  and medicinal animals .
The results of this study can be utilized to develop functional foods, pharmafoods, and new ethnomedicinal practices for gastrointestinal disorders in these communities and other regions within Korea.
2. Research Area and Method
2.1. Natural and Social Environments of Research Area
The study area consists of the southern region of the Korean peninsula and its many islands, which lie between 33° 06′N to 36° 09′N latitude and 125° 58′E to 128° 18′E longitude (Figure 1). The total population in 2012 of the study area was 1,161,002. The area measures approximately 2,410,434 km2 and includes five provinces, four cities, and eight counties in its administrative district . The annual precipitation is around 1,200~2,300 mm in which the coastal area generally receives more rainfall than the inland regions. The annual average temperature of the inland regions is 13°C, while Jeju Island records 16.2°C . The natural and social environments of the three national parks are summarized in Table 1.
*JNP: Jirisan National Park, GNP: Gayasan National Park, HNP: Hallasan National Park.|
2.2. Investigative Method
Field investigations were conducted from March 2009 to November 2012. Proper data was collected using participant observations and indepth interviews, as the informants also became investigators themselves through attending informal meetings, open and group discussions, and overt observations with semistructured questionnaires [21, 26].
The content of the semistructured questionnaires was composed of diverse information regarding medicinal species used to treat gastrointestinal disorders, including local names, used parts, methods of preparation, manufacturing and administration, dosage, and the usable duration regarding each curable formula [21, 27, 28].
All specimens were collected during their flowering or fruiting seasons and were organized utilizing the normal specimen manufacturing method [20, 27]. The voucher specimens were deposited for preservation in the herbarium of Jeonju University. The precise identification of species mentioned by the informants was performed in accordance with Lee , Lee , Ahn , Lee , and Park . Scientific names were confirmed by the National Knowledge and Information System for Biological Species of Korea .
2.3. Quantitative Analysis
2.3.1. Informant Consensus Factor (ICF)
The ICF was used to analyze the agreement degree of the informants’ knowledge about each category of disorders [17, 18]. The ICF was calculated using the following formula: where is the number of use reports of informants for a particular gastrointestinal disorder and is the number of species used by all informants for a particular gastrointestinal disorder.
2.3.2. Fidelity Level (FL)
The FL was employed to determine the most important species used for treating certain gastrointestinal disorders by the local practitioners and the elderly people living in the study area [19–21]. The FL was calculated using the following formula: where is the number of informants that mentioned the specific species used to treat certain disorders and is the total number of the informants who utilized the species as medicine for treating any given disorder.
2.3.3. Internetwork Analysis (INA)
Internetwork analysis does not focus on the independent characteristics of an individual within the community but considers the results of the interrelationship among each individual of a community. INA has been applied within communities for various ethnographical problems, including ethnogenesis  and obesity [36–38]. However, the INA had yet to be applied to ethnomedicinal knowledge, although it has been included in relation to its ethnographical properties.
Our research has newly applied this method in order to attain more internetwork information from the treatment of ethnomedicinal practices on gastrointestinal disorders within communities in Korea. The results of the INA of disorders and medicinal species were analyzed using UCINET (Ver. 6.460) and NetDraw (Ver. 2.125) software programs [39, 40].
3. Results and Discussion
3.1. Ethnographic Characteristics of the Region
The ethnomedicinal practices for gastrointestinal disorders were recorded by 507 informants (133 men and 374 women) at 185 sites (Figure 1). The average age of the informants was 76 years, with a range in age from 43 to 95, with residents living more than 30 years in the study area. The ethnographical characteristics of the communities are summarized in Table 2.
3.2. Analysis of Ethnomedicinal Practices
24 types of gastrointestinal disorders were treated by ethnomedicinal practices, which included abdominal pain, acute gastroenteritis, constipation, and other conditions (Table 3). The 24 types recorded in this study were similar to previous research, which classified 14 types of respiratory system diseases, 29 types of digestive system diseases, and 23 types of pain relief treatments [14, 16, 21]. Among them, 20 types of disorders were recorded in the communities living within JNP, followed by the 16 types of disorders within HNP, and the 11 types of disorders in GNP (Table 4).
*A: animal, P: plant, F: fungi, and AL: alga.|
**Region: JNP: Jirisan National Park, GNP: Gayasan National Park, and HNP: Hallasan National Park.
A total of 490 ethnomedicinal practices recorded from the communities were classified into 110 families, 176 genera, and 220 species that included plants, animals, fungi, and alga (Table 4). Among these species, plants totaled 361 ethnomedicinal practices based on 142 species, while animals included 119 ethnomedicinal practices based on 71 species. Fungi recorded 9 ethnomedicinal practices based on six species while alga included one ethnomedicinal practice based on one species. These usage patterns were different from Korean traditional medicine, in which plants are used relatively much more than animals. Research confirms that communities have focused on the functional supplements from these ethnomedicinal practices rather than seeking after an actual cure for their gastrointestinal disorders.
The residents of these communities have applied the ethnomedicinal practices for gastroenteric trouble and indigestion more than any other disorder. Namely, the number of medicinal species and ethnomedicinal practices for gastroenteric trouble consisted of 94 species (42.7% of the total species) and 179 ethnomedicinal practices (36.5% of the total practices). Indigestion used 72 species (32.7% of the total species) and 131 ethnomedicinal practices (26.7% of the total practices) (Table 5).
Also, the number of informants who mentioned gastroenteric trouble and cases of indigestion occupied 28.9%, which totaled 30.0% of the whole, respectively (Table 5). As a result, the communities tended to use ethnomedicinal practices to care for their overall health instead of as a cure for a long-term condition.
For plants, 29 used parts were used in practice, while 14 used parts of animals and one used part of fungi and alga were used in treatment. Preparations of the plants consisted of 41 kinds, with 16 preparations for animals, six preparations for fungi, and one preparation for alga (Table 4). These usage patterns are similar to previous research for other diseases [14–16].
3.3. Quantitative Analysis
3.3.1. Informant Consensus Factor (ICF)
The informant consensus factor ranges from 0 to 1, where the increasing values indicate a higher rate of informant consensus among the category of disorders.
The category with the highest degree of consensus from the informants were enteritis and gastralgia (1.0), followed by indigestion (0.94), constipation (0.93), abdominal pain and gastroenteric trouble (0.92), and gastric ulcers (0.91). The lowest degree of consensus was for gastroptosis, enterotoxin, hema feces, and other disorders (Table 6). These results denote that ethnomedicinal practices have been applied more often to minor health issues related to gastrointestinal disorders.
|−: Ailments were not mentioned in each national park.|
+: Below 0.40.
Generally, people suffering from serious gastrointestinal disorders have been treated in the hospital using conventional medicine or Korean traditional medicine. However, ethnomedicinal practices have been used to cure minor disorders.
Comparative consideration to results of the ICF among the three national parks and the agreement of consensus (ICF value, 1.00) from the informants in HNP obtained eight disorders, which include dysentery, gastralgia, gastric cancer, gastritis, hookworm, stomach cramps, stomach problems, and vomiting, while JNP and GNP depicted only enteritis and constipation, respectively.
These results confirm that the people of HNP have nearly the same ethnomedicinal knowledge for the treatment of gastrointestinal disorders because the communities have been isolated from other communities for many years.
3.3.2. Fidelity Level (FL)
The FL is useful for identifying the informants’ most preferred species in use for treating certain gastrointestinal disorders. This information reveals that the informants had a tendency to rely on one specific species for treating one specific disorder rather than for several different disorders. The FL values in this study varied from 1.0% to 100%.
Generally, a FL of 100% for a specific species indicates that all of the use-reports mentioned the same species for a specific treatment .
This study determined 71 species of plants with a FL of 100%, even without considering species that were mentioned more than two times (Table 3). Among them, plants with a FL of 100% in JNP totaled 52 species, followed by 40 species in GNP, and 23 species in HNP.
Disorders containing a higher number of species assessed to a FL of 100% were gastroenteric trouble (19 species) and cases of indigestion (22 species).
Special attention was given to important species (N, Np) with a FL above 100%, regarding the viewpoint of the number of times mentioned and the consensus level for the specific disorders, which include Spiraea prunifolia f. simpliciflora Nakai (224, 224), Impatiens balsamina L. as plants and Acetes japonicus Kishinouye (17, 17) as an animal cure for indigestion, Xanthium strumarium L. and Petasites japonicas (Siebold and Zucc.) Maxim. as plants used for curing gastroenteric trouble, Zinnia violacea Cav. and Platycarya strobilacea Siebold and Zucc. as plants used in treating abdominal pain, and Viola verecunda A. Gray as a plant used in treating dysentery (Table 3).
Through further study, these species possess a much higher potential in being used in the development of new functional supplements for treating specific gastrointestinal disorders.
3.3.3. INA between Gastrointestinal Disorders and Medicinal Species
INA has originally analyzed social phenomenon and trends through the internetwork of components . Our research has attempted to analyze the interrelationship between gastrointestinal disorders and the medicinal species recorded in the communities.
Considering Figure 2 about the internetwork between disorders and the medicinal species within all communities of this study, all medicinal species are grouped in the center for indigestion, diarrhea, abdominal pain, and gastroenteric trouble (Figure 2(a)), respectively. This distribution pattern is similar to the results of JNP and GNP. However, in case of HNP, indigestion is separated from the main disorders groups. This difference caused that the communities of HNP have been separated from the land communities for a long period of time.
In regard to the INA distribution map for JNP, the locations for the disorders of hema feces, intestinal disease, and hematemesis were fairly distinct from the four main disorders groups. Also, the cure for enteritis, hookworm, intestinal disease, stomach cramp, and stomachic is applied for only one medicinal species (Figure 2(b)).
In the case of GNP, gastritis, gastric ulcers, heartburn, and stomach problems were located as a distinct group separated from the four main disorder groups. Because this group consisted of minor stomach ailments having similar inclination, Zanthoxylum piperitum (L.) DC., Potentilla chinensis Ser., Euonymus alatus (Thunb.) Siebold, Atractylodes ovate (Thunb.) DC., and Ulmus davidiana var. japonica (Rehder) Nakai worked as possible cures as they possessed a high possibility in containing the same components for treatment (Figure 2(c)).
Within HNP, indigestion, intestinal disease, vomiting, stomach cramps, and enterotoxin were individually distinct from the three main disorder groups. This distribution pattern suggests that the application width of medicinal species to treat each disorder is limited for treating each disorder relative to the other communities (Figure 2(d)).
This research is the first study in the world to analyze and compare the ethnomedicinal practices of communities for treating gastrointestinal disorders. As the research method of this study, comparative quantitative analysis will contribute to the availability of orally transmitted ethnomedicinal knowledge. Additionally, the results of this study are confirmed due to the results obtained through investigation by 507 informants within the 185 research sites.
From this research, the recording of 490 ethnomedicinal practices being applied to the use of 220 medicinal species to treat 24 gastrointestinal disorders was extremely valuable. Particularly, the present usage of various medicinal species displays evidence as to which ethnomedicinal practices are continuously transmitted within the communities. However, this present situation is not sustainable because the communities of these study areas consist of an aging society. It has become necessary for appropriate measures to be taken to conserve these ethnomedicinal practices.
Our research suggests that treatment for gastroenteric trouble and indigestion among the gastrointestinal disorders uses ethnomedicinal practices more than any other type of treatment, as the communities used 75.5% of all medicinal species for treating these two diseases, 63.3% of the total number of all ethnomedicinal practices, and mentioned by 58.9% of all informants. Also, these two disorders contained the highest numbers of medicinal species within a FL of 100%. Through further study, the ethnomedicinal practices for these conditions possess a much higher potential in being used in the development of new practices.
According to the number of medicinal species applied to ethnomedicinal practices and the number of disorders treated by these ethnomedicinal practices, the numbers of JNP were much higher than the other two national parks. It is inferred that the region of JNP was the original center of Korean traditional medicine.
On the other hand, the communities of HNP depict a higher degree of agreement in the consensus to ethnomedicinal practices. This data explains that the communities of HNP, as island people, were limited in their movement to other regions and strictly collected large amounts of independent ethnomedicinal knowledge, only sharing within their own communities, which was distinct from the inland communities.
These trends were confirmed by the results of the INA as the internetwork maps of JNP and GNP were similar, while the map of HNP was moderately different. These results are reflected by the three-dimensional patterns of the ethnomedicinal knowledge held within the communities of each national park.
More specifically, the use of INA as a tool of quantitative analysis in this study provides valuable internetwork maps between gastrointestinal disorders and medicinal species.
These maps are important data to understand the specific interrelationships between disease and ethnomedicinal practices in the intra- and intercommunities.
The authors believe that INA is a useful new tool for providing various interpretations to ethnomedicinal knowledge in the intra- and intercommunities. This study provides confidence in that the useful value of INA will extend beyond the existing understanding of ethnomedicinal knowledge for the future research of ethnomedicinal knowledge.
Conflict of Interests
The authors declare that there is no conflict of interests regarding the publication of this paper.
The authors are very grateful to all informants of the study area for sharing their oral traditional knowledge during the fieldwork surveys.
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