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.

Analysis of traditional knowledge in medicinal plants used by Yuan in Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied traditional knowledge of medicinal plants use of the Yuan in northern Thailand, documenting and analysing traditional medical practices and its trend in the younger generations. AIM OF THE STUDY: To providing useful information for appropriate and sustainable management under the urbanization and other developments and use of natural resources in their communities. In addition, traditional medicinal plant used, and knowledge that leads to discovery of new medicines can be promoted. MATERIALS AND METHODS: Traditional medicinal plant knowledge of the Yuan in Lamphun province was studied from October 2009 through September 2011 in order to determine the important medicinal plant species and dominant use-categories in 5 villages. In each village, questionnaire interviews about medicinal plants uses were applied to 30 informants (5 informants per each of six stratified age groups). The relative importance of plant species was captured by calculation of use value (UV). Likewise, the dominant use-categories were determined by calculation of the informant agreement ratio (IAR). Correlations between informants' age and number of medicinal plants known by them were determined with the coefficient of determination (R(2)). RESULTS: A total of 93 medicinal plant species in 82 genera and 49 families were recorded in the five villages. The most important species of medicinal plants were Aloe vera (L.) Burm.f., Andrographis paniculata Ness, Chromolaena odorata (L.) R.M.King and H.Rob., Jatropha podagrica Hook., and Thunbergia laurifolia Lindl. which had UVs of 1.02, 1.01, 0.75, 0.71, and 0.65, respectively. Likewise, the most dominant use-categories were injuries, which accounted for 0.91 of the IAR. The age of informants and medicinal plants reported by each of them were positively correlated (R(2)=0.96, p<0.01). CONCLUSIONS: Most of the Yuan's traditional medicinal plant knowledge is used for treating basic ailments. However we should be concerned that there is an imminent danger that it will be lost in the near future because their lifestyle was changing.

Medicinal plants used in Hmong women's healthcare in northern Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied traditional knowledge of medicinal plants used for women's healthcare in three Hmong villages in northern Thailand and determined how prevalent such knowledge is. We documented traditional medical practices and determined which of the species used are culturally important among the Hmong. MATERIALS AND METHODS: We interviewed six key informants and 147 non-specialist informants about their traditional knowledge of medicinal plants used in Hmong women's healthcare. We selected nine species that were known in all three villages as the domain for questionnaire interviews with 181 additional and randomly selected non-specialist informants. We calculated the Cultural Importance index (CI) for each species and use category. We tested normality of the data, age correlations, and gender correlations with Kolmogorov-Smirnov tests, Spearman's rank correlation coefficient, Kruskal-Wallis test, and Mann-Whitney tests. RESULTS: We documented traditional knowledge of 79 medicinal plants used in women's healthcare. Of these, three species were culturally important to the Hmong. Our questionnaire interviews revealed significant difference in traditional medicinal plant knowledge between genders and age groups. CONCLUSIONS: The Hmong people in northern Thailand possess large amounts of traditional knowledge related to women's healthcare and plants used for this purpose. However, this knowledge, even for the culturally important species, is not possessed by all Hmong and there were signs of knowledge erosion. Preservation of the Hmong intellectual heritage related to medicinal plants used in women's healthcare requires intensive traditional knowledge dissemination to the young Hmong generation.

Medicinal plant knowledge and its erosion among the Mien (Yao) in northern Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied local knowledge and actual uses of medicinal plants among the Mien in northern Thailand, documenting traditional medical practices and its transfer between generations. AIM OF THE STUDY: With the assumption that discrepancies between knowledge and actual use represent knowledge erosion, we studied whether actual use of medicinal plants corresponded to people's knowledge of such uses. MATERIALS AND METHODS: We used local knowledge from four specialist informants as the domain for semi-structured interviews with 34 randomly selected non-specialist informants. We calculated informant consensus, use value, and fidelity level for each species and use category and performed statistical analyses with Kolmogorov-Smirnov tests, Pearson correlation coefficient, Spearman's rank correlation coefficient, and paired-sample t-tests. RESULTS: We found significant discrepancies between knowledge and actual use of medicinal plants. The number of known and actually used plants increased with increasing informant age and decreased with increasing years of formal education. CONCLUSIONS: Medicinal plant knowledge and use in these Mien communities is undergoing inter-generational erosion because of acculturation and interrupted knowledge transmission. Preservation of Mien medicinal plant intellectual heritage requires continued documentation concerning use, conservation, and sustainable management of this resource, which should be publicized to younger Mien.

A comparative study on medicinal plants used in Akha's traditional medicine in China and Thailand, cultural coherence or ecological divergence?

AIM OF THE STUDY: The survey aims to study the effect of geographic separation of ethnic groups on local knowledge of medicinal plants used by Akha people in Thailand and China, who were separated 100-120 years ago, to see how different the two geographically distinct but culturally similar groups were in this respect. MATERIALS AND METHODS: Interviewing 10 villagers in each of five Akha villages, three in Thailand and two in China, about which plants they used and how they used them. RESULTS: A total of 95 medicinal plants registered in the five villages only 16 were shared between China and Thailand. Otherwise the use patterns were quite similar with respect to which plant families and plant growth forms were used and also in terms of in which habitats the Akha found their medicinal plants. CONCLUSIONS: The moving to a different site has forced the Akha to find a new set of species, but that when using these new species they have maintained other traditions relating to medicinal plants.