Tangjitman et al. Journal of Ethnobiology and Ethnomedicine (2015) 11:27 DOI 10.1186/s13002-015-0011-9 JOURNAL OF ETHNOBIOLOGY AND ETHNOMEDICINE RESEARCH Open Access Ethnomedicinal plants used for digestive system disorders by the Karen of northern Thailand Kornkanok Tangjitman1, Chalobol Wongsawad1*, Kaweesin Kamwong2, Treetip Sukkho1 and Chusie Trisonthi1 Abstract Background: Digestive system disorders have a substantial effect on worldwide morbidity and mortality rates, including in Thailand, where the majority of the rural areas have a lack of proper sanitation and awareness about disease prevention. This has led to the prevalence of different types of digestive diseases. Karen people in Thailand still use medicinal plants as first aid remedies in treating these diseases. Therefore, this study aimed at documenting the plants used to cure and prevent different types of digestive system disorders by Karen people of Chiang Mai Province, northern Thailand. Methods: Ethnomedicinal data were collected from six key informants and 172 non-specialist informants regarding their traditional knowledge of medicinal plants. Quantitative approaches were used to determine Use Value (UV), Informant Consensus Factor (ICF) and Fidelity Level (FL) values. Results: The study revealed that 36 medicinal plant species belonging to 31 genera and 24 families were used to treat digestive system disorders. The most prevalent plant families were Zingiberaceae (6 species), Euphorbiaceae (4 species) and Fabaceae (4 species). Leaves were the most commonly used plant part accounting for 32.6% of the plants, followed by the bark (18.6%). About 60% of the administrations were given orally by potion (60%) and consumption as food was also indicated (14%). The highest ICF values were recorded for carminative disorders, stomachaches, geographic tongue, constipation, appetite stimulants and food poisoning (1.00 each) indicating the best agreement among the informants knowledge of medicinal plants that were used to treat aliments in these categories. The highest fidelity level values were recorded for Punica granatum (100.00), Psidium guajava (95.45), and Gymnopetalum integrifolium (90.91) showing conformity of knowledge on species with the best healing potential. Conclusion: Medicinal plants still play an important role among Karen culture. The present information on these medicinal plants, which have high UV and FL values, may serve as the baseline data to initiate further research for the discovery of new compounds and the biological activities of these potential plant remedies. Further research on these plants may provide some important clues for the development of new drugs for the treatment of digestive system diseases. Keywords: Ethnobotany, Traditional knowledge, Gastrointestinal, Chiang Mai, Pharmacology, Toxicology Introduction Moreover, in South-East Asia, diarrhea has been the cause There are a wide number of digestive system disorders, of 10% of deaths among children below the age of 5 years. which impose a substantial influence on morbidity For the last couple of years, there has been a global and mortality rates, worldwide. The World Health trend in the renewal of interest in a traditional system of Organization (WHO) [1] reported that digestive system treatments. Ethnomedicinal plant studies have become disorders, particularly diarrhea, was the fifth leading cause of particular interest and have become increasingly more of global mortality, as approximately 100 million people valuable in the development of health care and conser- died worldwide in 2012 from these types of disorders. vation programs in different parts of the world [2]. The WHO has recognized the role of traditional medicine * Correspondence: [email protected] in the primary health care system [3]. In developing 1Department of Biology, Faculty of Science, Chiang Mai University, Huaykaew Road, Chiang Mai 50200, Thailand Full list of author information is available at the end of the article © 2015 Tangjitman et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Tangjitman et al. Journal of Ethnobiology and Ethnomedicine (2015) 11:27 Page 2 of 13 countries, medicinal plants continue to be a main Materials and methods source of medication. It has been estimated that ap- Study area proximately 88% of the inhabitants of underdeveloped Data were collected in Chiang Mai province, northern countries rely mainly on traditional medicine for their Thailand (Figure 1). Chiang Mai province is surrounded primary form of medicinal health care [4]. by high mountain ranges and covers an area of approxi- Thailand has a rich population of ethnic people who mately 20,107 km2 [13]. Forest area covers 17,640 km2 still maintain a traditional knowledge of medicinal plants (72.01%) of Chiang Mai’s total area. The major types of that are used in the treatment of illnesses [5]. Studies of forests in Chiang Mai are mixed deciduous forests, trop- several ethnomedicinal plants have been carried out ical evergreen forests and dry dipterocarp forests. Several among several ethnic groups in Thailand. However, national parks are also located in the province (Doi there has been no comprehensive study of the medicinal Inthanon, Doi Suthep-Pui, Mae Ping, Sri Lanna, Huay plants used to treat digestive system disorders in Nam Dang, Mae Phang and Chiang Dao). Six Karen Thailand. Digestive system disorders were identified as villages (Huay Hea, Mai Lan Kam, Kew Pong, San the third highest cause of morbidity among Thai Muang, Mai Sa Wan and Huay Pu Ling) were selected people in 2010 [6]. More than 1 million people have as study sites. These villages are located at 746, 692, appealed to the public health system for the treatment 1,010, 1,050, 1,190 and 1,050 m.l.s., respectively and they of these diseases. Besides, Jansongduang et al. [7] re- are surrounded by natural forests. There are 14 house- vealed that people who typically reside in remote areas holds in Huay Hea, 45 in Mai Lan Kam, 49 in Kew Pong, especially hill tribe people in northern Thailand likely 51 in San Muang, 18 Mai Sa Wan and 32 in Huay Pu drink water from forest streams without any antisep- Ling. They typically consume upland rice and supple- ticsandusedthesamewaterforbathing,raisinglive- ment their meals with vegetables and animal products stock, and sewage disposal. These practices result in for their diet. The villagers derive their main monetary poor water quality and often lead to digestive system income through the sale of forest products, livestock problems. Moreover, previous ethnobotanical studies and as labor in northern Thai fields. Their economic in northern Thailand showed that digestive diseases status is generally considered to be poor. The Karen had the highest number medicinal plants recorded society is matriarchal. Each household contains only one compared with other illness categories and most hill or two generations. Most Karen people in Kew Pong, tribe people had experience curing these diseases with San Muang, Mai Sa Wan and Huay Pu Ling are Christian medicinal plants [7-10]. This reflects that digestive system whereas those of Huay Hea and Mai Lan Kam consider disorders are also important morbidity among Thai hill themselves Buddhist. tribe people. This study documents the traditional medicinal plants Data collection that are used for digestive system disorders by the Karen To collect plants and associated ethnomedicinal infor- which comprise the largest hill tribe in Thailand [11]. mation relating to digestive system disorders from the The Karen originated in Tibet and had migrated to other Karen, field trips were conducted between 2006 and parts of Southeast Asia, particularly Myanmar [12]. 2011. Initial contacts were made to the village head- From the 18th century onwards they began to cross the men, to whom we explained the purpose and tech- Salween River and moved into Thailand, where they niques of the proposed research. Subsequently the settled in the high mountains of Chiang Mai, Mae headmen explained the purpose and methods of the Hong Son and Lamphun provinces, as well as other study to the villagers who gave their informed consent areas. In 2003, the Karen people constituted 48% of the for the publication of this report and any accompany- total hill tribe population in the region with a popula- ing images. The information on medicinal plants was tion more than 430,000 Karens in Thailand [11]. As gathered through interviews, guided tours, and partici- they typically reside in the mountain areas, the Karen pativeobservationinhomegardens,cultivatedfields people have limited access to public healthcare systems. and nearby forests. The plants used were indentified They have therefore accumulated a rich experience related (local name), photographed and samples were col- to preventing and treating diseases with herbal remedies, lected for the preparation of herbarium specimens, andtheyhavedevelopedadistinctiveknowledgeof which were deposited at the Faculty of Science, Chiang traditional medicine. This traditional knowledge has Mai University and the Queen Sirikit Botanical been handed down