Ethnomedicinal plant diversity in Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: Plants have provided medicine to humans for thousands of years, and in most parts of the world people still use traditional plant-derived medicine. Knowledge related to traditional use provides an important alternative to unavailable or expensive western medicine in many rural communities. At the same time, ethnomedicinal discoveries are valuable for the development of modern medicine. Unfortunately, globalization and urbanization causes the disappearance of much traditional medicinal plant knowledge. AIM OF THE STUDY: To review available ethnobotanical knowledge about medicinal plants in Thailand and to estimate its diversity. METHODS: Information about ethnomedicinal uses of plants in Thailand was extracted from 64 scientific reports, books, and theses produced between 1990 and 2014. Plant identifications in the primary sources were updated to currently accepted names following The Plant List website and the species were assigned to family following the Angiosperm Phylogeny Website. Use Values (UV) were calculated to estimate the importance of medicinal plant species (UVs) and families (UVf). Medicinal use categories, plant parts used, preparations of the medicine, and their applications were noted for each use report. RESULTS: We found 16,789 use reports for 2187 plant species in 206 families. These data came from 19 ethnic groups living in 121 villages throughout Thailand. The health conditions most commonly treated with medicinal plants were in the categories digestive system disorders, infections/infestations, nutritional disorders, muscular-skeletal system disorders, and genitourinary system disorders. Plant families with very high use values were Fabaceae, Asteraceae, Acanthaceae, Lamiaceae, and Zingiberaceae and species with very high use values were Chromolaena odorata (L.) R.M.King & H.Rob., Blumea balsamifera (L.) DC., and Cheilocostus speciosus (J.Koenig) C.D.Specht. Stems and leaves were the most used plant parts, but also other parts of the plants were used in medicinal recipes. The most common way of using the medicinal plants was as a decoction in water. CONCLUSION: We found 2187 plant species that were used in traditional medicine in Thailand. Of these a few hundred had high use values, suggesting that they may produce bioactive compounds with strong physiological effects.

Ethnomedicinal plants used for digestive system disorders by the Karen of northern Thailand.

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.

Traditional knowledge on medicinal plant of the Karen in northern Thailand: a comparative study.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied traditional medicinal plant knowledge among the Karen in northern Thailand. AIM OF THE STUDY: To compare traditional medicinal knowledge in 14 Karen villages in northern Thailand and determine culturally important medicinal plant species in each Karen village. MATERIALS AND METHODS: We interviewed 14 key informants and 438 non-specialist informants about their traditional knowledge of medicinal plants. We tested normality of the data and correlations with distance to the nearest city using Kolmogorov-Smirnov tests and Spearman's rank correlation coefficient. Cluster analysis and cultural importance index (CI) were calculated for the similarity of medicinal plant used and culturally importance medicinal plant species among Karen villages respectively. RESULTS: In total 379 medicinal plant species were used. Number of medicinal plants used positively correlate with distance to the nearest city. Relatively low similarities of medicinal plant species and different CI values for species among the different areas were found. CONCLUSIONS: Traditional medicinal plants still play an important role in medicinal practice of the Karen. Local environments, availability of medicinal plant and distance between Karen villages and the nearest city affect the amount of traditional medicinal knowledge in each Karen village. The medicinal plants in this study with high CI values might give some useful leads for further biomedical research.