Epiphytic Orchid Diversity along an Altitudinal Gradient in Central Nepal.

Epiphytic orchids are common in subtropical forests, but little is known about the factors that determine their diversity. We surveyed two sites (north-facing Phulchowki and south-facing Shivapuri hills), in the sub-tropical forest in the Kathmandu valley, central Nepal. Along five transects per site, spanning an altitudinal gradient of 1525-2606 m a.s.l., we recorded all epiphytic orchids and the host species on which they were growing. The data were analyzed using a generalized linear model (GLM) and redundancy analysis (RDA). Species richness significantly decreased with increasing altitude and was higher in larger hosts and in places with high temperature. Species composition was affected by altitude, distance from the forest edge, host type, and precipitation. This study indicates that the most important factors affecting epiphytic orchid diversity was altitude, even if other factors were associated with patterns in composition. The low-altitude habitats with high species diversity are the best places for epiphytic orchids in this region. The altitudinal species richness and patterns in composition revealed by this study provide a baseline for further studies on epiphytic orchids.

Neopicrorhiza scrophulariiflora (Pennell) Hong: A comprehensive review of its traditional uses, phytochemistry, pharmacology and safety.

ETHNOPHARMACOLOGICAL RELEVANCE: Neopicrorhiza scrophulariiflora (Pennell) Hong is important medicinal plant that is native to the eastern Himalayas and Hengduan mountains in China. It is also distributed in Nepal, north east India, Bhutan and northern Myanmar. Plant parts are traditionally used against different kinds of diseases and various compounds present in different plant parts are also effective against many diseases. Thus, N. scrophulariiflora has a high potential to maintain human health. AIM OF THE REVIEW: Although N. scrophulariiflora is very important and widely studied plant species but there is no comprehensive up-to-date review of published and unpublished literature. So, in the present article we have compiled and critically commented on the botanical characteristics, traditional uses, plant growth and cultivation, micropropagation, conservation status, secondary metabolites, pharmacology and toxicity of the plant. MATERIALS AND METHODS: Extensive literature searches both electronic online databases (Google Scholar, Scopus, Springer Link, Web of Science, ScienceDirect, ResearchGate, PubMed, ChemSpider, USPTO, Google patents and Espacenet) and library visits in Nepal were carried out to collect the literature on information published prior to April 2019. RESULTS: N. scrophulariiflora was traditionally used for 82 ailments/diseases. There are 124 major phytochemicals extracted from the plant. Several compounds are effective in bioactivity. Pharmacologically, the plant is proved to be anti-atherosclerotic, antidiabetic and anti-inflammatory in-vivo studies, and antimicrobial, antimalarial, antioxidative, hepatoprotective, immunomodulatory and nerve growth factor potentiating from in-vitro studies. Renal improvement activities were confirmed from both in-vivo and in-vitro studies. Toxicological tests and a single clinical trial in human beings have supported the notion that the plant is not poisonous but beneficial for curing wide ranges of diseases. CONCLUSION: N. scrophulariiflora is valuable medicinal plant that can serve as promising source of non-harmful and potential medicinal herbal remedies for human beings.

Xanthones Content in Swertia multicaulis D. Don from Nepal.

The medicinal plant Swertia multicaulis D. Don was collected in Rasuwa District (Nepal) and the xanthone content of its ethyl acetate extracts was studied. The total amount of xanthones in S. multicaulis determined by HPLC reaches almost 13 g of xanthones per 1 kg of dry matter. The identification of xanthones in S. multicaulis was achieved by a combination of HPLC, LC⁻MS and LC⁻NMR. The final assignment of the individual chemical structures was provided by NMR, supported by preparative HPLC. In eight chromatographic peaks, four major xanthones were identified­1,3-dihydroxy-5,8-dimethoxyxanthone, 1-hydroxy-3,5,8-trimethoxyxanthone, bellidifolin (1,5,8-tri-hydroxy-3-methoxyxanthone), and decussatin (1-hydroxy-3,7,8-trimethoxyxanthone).

Traditional uses of medicinal plants in gastrointestinal disorders in Nepal.

ETHNOPHARMACOLOGICAL RELEVANCE: Gastrointestinal disorders cause morbidity and can lead to mortality, especially in the developing world where sanitation is deficient. A large part of the human population relies on medicinal plants for treating various diseases, including gastrointestinal disorders. The present review summarizes the traditional uses of medicinal plants of Nepal used to treat gastrointestinal disorders, and evaluates their bio-efficacy based on a review of the available phytochemical and pharmacological literature. MATERIAL AND METHODS: We searched different electronic databases and libraries for the literature on medicinal plants used in Nepal to treat gastrointestinal disorders. For each species, we also searched the literature for information on conservation status, as well as for phytochemical and pharmacological studies in support of the ethnobotanical information. We used principal component analysis to explore the relation among disorders and plant families, plant life forms, plant parts and preparation modes. We also performed permutation tests to determine if botanical families were used more often than expected considering their availability in the Nepali flora. RESULTS: We documented a total of 947 species belonging to 158 families and 586 genera used to treat gastrointestinal disorders in Nepal. Diarrhea was the disorder treated by the highest number of species (348), followed by stomachache (340) and dysentery (307). Among the reported species, five were endemic to Nepal, whereas 16 orchid species were protected under CITES Appendices II and III. The randomization test showed that species belonging to 14 families were used less often than expected, whereas plants belonging to 25 families were used more often than expected. The PCA scatter plot showed distinct groups of gastrointestinal disorders treated with similar plant life forms, plant parts, and/or preparation modes. We found 763 phytochemical studies on 324 species and 654 pharmacological studies on 269 species. CONCLUSION: We showed the diversity and importance of medicinal plants used to treat gastrointestinal disorders in the traditional health care system of Nepal. As such disorders are still causing several deaths each year, it is of the utmost importance to conduct phytochemical and pharmacological studies on the most promising species. It is also crucial to increase access to traditional medicine, especially in rural areas. Threatened species need special attention for traditional herbal medicine to be exploited sustainably.

Medicinal plants used by the Tamang community in the Makawanpur district of central Nepal.

BACKGROUND: We can conserve cultural heritage and gain extensive knowledge of plant species with pharmacological potential to cure simple to life-threatening diseases by studying the use of plants in indigenous communities. Therefore, it is important to conduct ethnobotanical studies in indigenous communities and to validate the reported uses of plants by comparing ethnobotanical studies with phytochemical and pharmacological studies. MATERIALS AND METHODS: This study was conducted in a Tamang community dwelling in the Makawanpur district of central Nepal. We used semi-structured and structured questionnaires during interviews to collect information. We compared use reports with available phytochemical and pharmacological studies for validation. RESULTS: A total of 161 plant species belonging to 86 families and 144 genera to cure 89 human ailments were documented. Although 68 plant species were cited as medicinal in previous studies, 55 different uses described by the Tamang people were not found in any of the compared studies. Traditional uses for 60 plant species were consistent with pharmacological and phytochemical studies. CONCLUSIONS: The Tamang people in Makawanpur are rich in ethnopharmacological understanding. The present study highlights important medicinal plant species by validating their traditional uses. Different plant species can improve local economies through proper harvesting, adequate management and development of modern techniques to maximize their use.

Rheum australe D. Don: a review of its botany, ethnobotany, phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Rheum australe D. Don (Polygonaceae) has been commonly used in traditional medicine for a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to infectious diseases. AIM OF THE REVIEW: To provide the up-to-date information that is available on the botany, traditional uses, phytochemistry, pharmacology and toxicology of Rheum australe. Additionally, to highlight the possible uses of this species to treat different diseases and to provide a basis for future research. MATERIALS AND METHODS: The present review covers the literature available from 1980 to 2011. The information was collected from scientific journals, books, theses and reports via a library and electronic search (Google Scholar, Web of Science and ScienceDirect). RESULTS: Ethnomedical uses of Rheum australe have been recorded from China, India, Nepal and Pakistan for 57 different types of ailments. The phytochemical studies have shown the presence of many secondary metabolites belonging to anthraquinones, stilbenes, anthrones, oxantrone ethers and esters, chromones, flavonoids, carbohydrate, lignans, phenols and sterols. Crude extracts and isolated compounds from Rheum australe show a wide spectrum of pharmacological activities, such as antidiabetic, anti-inflammatory, antifungal, antimicrobial, antioxidant, anticancer, hepatoprotective and immune-enhancing activities, as well as a usefulness for improving renal function. CONCLUSION: Rheum australe has been widely used source of medicine for years without any adverse effects. Many studies have provided evidence for various traditional uses. However, there is a need for additional studies of the isolated compounds to validate the traditional uses in human models. The present review on the botany, traditional uses, phytochemistry and toxicity has provided preliminary information for further studies and commercial exploitations of the plant.

Ethnobotanical study of medicinal plants from the Humla district of western Nepal.

AIM OF THE STUDY: The present paper documents the uses of plants in traditional herbal medicine for treatment of human and veterinary ailments in four village development committees in the Humla district of western Nepal. It also determines the homogeneity of informant's knowledge on medicinal plants suitable for different ailment categories and the most preferred plant species used to treat each ailment category in the study areas. MATERIALS AND METHODS: The ethnobotanical information was collected through semi-structured interviews and key informant discussion. The data were analyzed through informant consensus factor (ICF), fidelity level (FL) and use value (UV). RESULTS: We documented 161 plant species belonging to 61 families and 106 genera used for treating 73 human and 7 veterinary ailments. We also documented culinary uses and additional uses for 67 and 33 species of medicinal plant species respectively. Most medicines were prepared in the form of powder and used orally. Roots were most frequently used plant parts. The uses of 93 medicinal plants were not mentioned in any previous studies. Gastro-intestinal ailments have the highest ICF (0.40) whereas opthalmological uses have the lowest (zero) ICF. Mentha spicata and Rumex hastatus has the highest FL (100% each) both being used for gastro-intestinal ailments and Delphinium himalayai has the lowest (47.4%) for veterinary uses. CONCLUSIONS: ICF values indicated that there was high agreement in the use of plants in gastro-intestinal ailment category among the users. FL or UV values indicated the most preferred plant species used in study areas. These preferred plant species could be prioritized for conservation and subjected to further studies related to chemical screening for their authenticity. Most of the medicinal plants of the region are collected in the wild and are often harvested for trade. Sustainable harvesting methods and domestication of the highly traded species is thus needed in the study areas.