Efficient tunable cascaded Raman source with all-silica fibers based on 2-µm DSR pulse pumping.

We present an efficient tunable all-silica-fiber 2nd-order cascaded Raman pulse laser utilizing 2-µm dissipative-soliton-resonance (DSR) rectangular pulses for pumping and highly GeO2-doped silica fiber as Raman gain medium. When pumped at 1966.5 nm, the maximum 1st-order Raman optical conversion efficiency is up to 64.4% at 2153 nm, with 92.4% spectral purity and 0.39-W average power. The maximum 2nd-order Raman optical conversion efficiency is 19.3% at 2370 nm, with 39.2% spectral purity and 0.25-W average power. To our knowledge, these conversion efficiencies and spectral purities represent the highest levels achieved in a mid-infrared all-silica-fiber cascaded pulsed Raman laser. Additionally, by adjusting the central wavelength of the DSR seed pulse, the 2nd-order Raman light can be tuned within a range of 41 nm (2354∼2395 nm). Our system provides a simple and easy-to-implement solution for realizing efficient tunable cascaded pulsed Raman lasers in the 2.4-µm band.

Metabolomic and chemometric analyses of St. John's wort and related Asian Hypericum species linked to bioactivity.

ETHNOPHARMACOLOGICAL RELEVANCE: Plants in the genus Hypericum (Hypericaceae), include more than 500 species worldwide, and many are valued for their medicinal properties, and are used as traditional herbal medicines. However, only H. perforatum is officially recognized as herbal drug in several pharmacopoeias, and used as an antidepressant clinically. Hypericum perforatum had been used as an herbal medicine since the Han Dynasty (206 B.C. -220 A.D.) in China. It taxonomically belongs to the section Hypericum in the genus Hypericum. There are about 42 species in the section Hypericum, with six species occurring in China. All six are recorded as traditional herbal medicines for treating aliments, including hepatitis, malaria, traumatic hemorrhage, irregular menstruation, wounds, and bruises. AIM OF THE STUDY: The study aimed to characterize the chemical profiles of five phylogenetically related Hypericum species, and compare their metabolites with three H. perforatum products. Informed by ethnobotanical use, the extracts prepared from the five species were further investigated into anticancer, anti-inflammatory and antiplasmodial activity. This study tested the hypothesis that systematic metabolomic and bioactivity characterization of species in section Hypericum will help to validate their phytotherapeutic use and reveal potential drug lead compounds. MATERIALS AND METHODS: Targeted and non-targeted metabolic analyses coupled with chemometrics were conducted on H. perforatum and four medicinal species, H. attenuatum, H. enshiense, H. erectum, and H. faberi, native to China from section Hypericum. UPLC-QTOF-MS/MS and UPLC-TQD-MS/MS were used for non-targeted and targeted metabolic analyses, respectively. Cytotoxicity bioassays on four cancer cell lines, anti-inflammation tests and anti-plasmodial activity on Plasmodium falciparum 3D7, selected based on traditional medicinal use, were evaluated on extracts from Hypericum species. Progenesis QI and EZinfo were used for chemometrics analysis to link the chemical profile and bioassay activity to aid in the identification of bioactive compounds. RESULTS: In total, 58 compounds were identified from the five species, including compounds with well-characterized bioactivity. Hypericum attenuatum, H. erectum, and H. perforatum, displayed the highest cytotoxicity, and contain the cytotoxic compounds petiolin A, prolificin A, and hypercohin G, respectively. Hypericum faberi and H. perforatum showed the highest anti-inflammatory activity, with pseudohypericin, quercetin and chlorogenic acid being observed at higher concentrations. Hypericum perforatum and H. erectum showed anti-plasmodial activity, with higher hyperforin and xanthones in these species that may account for the anti-plasmodial activity. CONCLUSIONS: This study characterized the chemical differences among five Hypericum species using metabolomics. These ethnomedically important species were tested for their biological activities in three distinct in vitro assays. The ethnobotanical data were useful for identifying bioactive Hypericum species. Hypericum attenuatum, H. erectum and H. faberi are promising phytotherapeutic species, although they are much less studied than H. perforatum, St. John's wort. Combining ethnobotanical surveys with chemometric analyses and bioactivity screening can greatly enhance the discovery of promising active constituents.

Fiber-Optic-Based Biosensor as an Innovative Technology for Point-of-Care Testing Detection of Foodborne Pathogenic Bacteria To Defend Food and Agricultural Product Safety.

Food safety is a concerning issue globally. Foodborne-pathogenic-bacteria-derived foodborne disease outbreaks have increased the threat to human health. The accurate and rapid detection of foodborne bacteria is of great significance for food safety. A fiber-optic-based biosensor has emerged as a powerful technique for the point-of-care testing of foodborne bacteria in food and agricultural products. This Perspective discusses the opportunities and challenges of fiber-optic-based biosensors for foodborne bacteria detection. The corresponding solution strategies to promote the application of this innovative technology in food and agricultural product detection for food safety and human health are also discussed and proposed.

HS-SPME/GC×GC-TOFMS-Based Flavoromics and Antimicrobial Properties of the Aroma Components of Zanthoxylum motuoense.

Zanthoxylum motuoense Huang, native to Tibet, China, is a newly discovered Chinese prickly ash, which, recently, has increasingly attracted the attention of researchers. In order to understand its volatile oil compositions and flavor characteristics, and to explore the flavor difference between Z. motuoense and the common Chinese prickly ash sold in the market, we analyzed the essential oils of Z. motuoense pericarp (MEO) using HS-SPME/GC×GC-TOFMS coupled with multivariate data and flavoromics analyses. The common commercial Chinese prickly ash in Asia, Zanthoxylum bungeanum (BEO), was used as a reference. A total of 212 aroma compounds from the 2 species were identified, among which alcohols, terpenoids, esters, aldehydes, and ketones were the major compounds. The predominant components detected from MEO were citronellal, (+)-citronellal, and ß-phellandrene. Six components-citronellal, (E,Z)-3,6-nonadien-1-ol, allyl methallyl ether, isopulegol, 3,7-dimethyl-6-octen-1-ol acetate, and 3,7-dimethyl-(R)-6-octen-1-ol-could be used as the potential biomarkers of MEO. The flavoromics analysis showed that MEO and BEO were significantly different in aroma note types. Furthermore, the content differences of several numb taste components in two kinds of prickly ash were quantitatively analyzed using RP-HPLC. The antimicrobial activities of MEO and BEO against four bacterial strains and nine plant pathogenic fungi were determined in vitro. The results indicated that MEO had significantly higher inhibitory activities against most microbial strains than BEO. This study has revealed the fundamental data in respect of the volatile compound properties and antimicrobial activity of Z. motuoense, offering basic information on valuable natural sources that can be utilized in the condiment, perfume, and antimicrobial sectors.

Response Surface Optimization of Extraction Conditions for the Active Components with High Acetylcholinesterase Inhibitory Activity and Identification of Key Metabolites from Acer truncatum Seed Oil Residue.

The State Council of China has called for the comprehensive development and utilization of Acer truncatum resources. However, research on one of its by-products, namely seed oil residue (ASR), from seed oil extraction is seriously insufficient, resulting in a waste of these precious resources. We aimed to optimize the conditions of ultrasound-assisted extraction (UAE) using a response surface methodology to obtain high acetylcholinesterase (AChE) inhibitory components from ASR and to tentatively identify the active metabolites in ASR using non-targeted metabolomics. Based on the results of the independent variables test, the interaction effects of three key extracting variables, including methanol concentration, ultrasonic time, and material-to-liquid ratio, were further investigated using the Box-Behnken design (BBD) to obtain prior active components with high AChE inhibitory activity. UPLC-QTOF-MS combined with a multivariate method was used to analyze the metabolites in ASR and investigate the causes of activity differences. Based on the current study, the optimal conditions for UAE were as follows: methanol concentration of 85.06%, ultrasonic time of 39.1 min, and material-to-liquid ratio of 1.06:10 (g/mL). Under these optimal conditions, the obtained extracts show strong inhibitions against AChE with half maximal inhibitory concentration (IC50) values ranging from 0.375 to 0.459 µg/mL according to an Ellman's method evaluation. Furthermore, 55 metabolites were identified from the ASR extracted using methanol in different concentrations, and 9 biomarkers were subsequently identified as potential compounds responsible for the observed AChE inhibition. The active extracts have potential to be used for the development of functional foods with positive effects on Alzheimer's disease owing to their high AChE inhibition activity. Altogether, this study provides insights into promoting the comprehensive utilization of A. truncatum resources.

Protective effects of extracts from Acer truncatum leaves on SLS-induced HaCaT cells.

Introduction: A. truncatum Bunge (Sapindaceae or formerly Aceraceae) is a tall deciduous tree native to China. Traditionally, the leaves of A. truncatum are decocted and used by Chinese Mongolians, Koreans, and Tibetans to treat skin itching, dry cracks, and other skin ailments, which indicates A. truncatum leaves may have a potential inhibitory effect on various skin inflammations. Methods: To examine the protective effect against skin inflammations of A. truncatum leaf extract (ATLE), an in vitro dermatitis model was established using sodium dodecyl sulfate (SLS)-induced HaCaT cells. The anti-inflammatory effect of ATLE was evaluated by analyzing cell viability, apoptosis, reactive oxygen species (ROS), interleukin 6 (IL-6), and prostaglandin E2 (PGE2) levels. Results: Orthogonal experiments showed that the pretreatment with ATLE can reduce the IL-6 levels, PGE2 levels, and apoptosis increased in SLS-stimulated HaCaT cells, which indicates that ATLE has positive efficacy for dermatitis. Furthermore, three flavonoid compounds kaempferol-3-O-α-L-rhamnoside, quercetin-3-O-α-L-rhamnopyranoside, kaempferol-3,7-di-O-α-L-rhamnoside, and 1,2,3,4,6-Penta-O-galloyl-ß-D-glucopyranose (PGG) were isolated and identified. Among them, kaempferol-3,7-di-O-α-L-rhamnoside was isolated from this plant for the first time. These compounds have been proven to have an anti-inflammatory effect. They may contribute to the efficacy of A. truncatumin treating skin inflammation. Discussion: The results revealed that ATLE has the potential to be used as an additive in various skin care products to prevent skin inflammations and may be incorporated in formulations for topical application as a therapeutic approach against dermatitis.

Heavy metal(loid)s in agriculture soils, rice, and wheat across China: Status assessment and spatiotemporal analysis.

Heavy metal(loid)s (HMs) accumulation in agricultural soils, rice, and wheat is of particular concern in China, while the status and spatio-temporal distribution of HMs in the soil-crops system have been rarely reported at the national scale. This study aimed to summarize the overall pollution status, spatiotemporal patterns, and drivers of HMs in agricultural soil, rice, and wheat nationwide. The metal-polluted data from 1030 agricultural soils, rice, and wheat in China were collected from the literature published from 2000 to 2022. The results showed that Cd was the most prevailing contaminant in soils based on its spatiotemporal distribution and accumulation. The pollution cases and severe pollution percentage of Cd (103 %) and Hg (128 %) show an increasing trend pattern. Mining activities are the main anthropogenic sources of agricultural soil HMs in China. Cd and Pb had the highest exceedance rate in rice (33.5 and 32.2 %) and wheat (25.8 and 30.3 %). The rice from Hunan, Fujian, and Guangxi showed the highest average concentration of Cd and Pb, respectively, while wheat samples from Hubei had the greatest exceedance rate of Pb. Besides, HMs in crops was not usually corresponding to soil HMs but increased gradually from north to south areas. Several mitigation strategies and accurate health risk assessments model of HMs based on bioavailability were also proposed and recommended. Collectively, this review provides valuable information to improve the management of farmland nationwide, optimize the accurate risk assessment, and reduce HMs pollution.

Ethnobotanical study on herbal tea drinks in Guangxi, China.

BACKGROUND: Herbal tea drinks, different from classical Camellia beverages, are a wide variety of herbal drinks consumed for therapeutic purposes or health promotion. Herbal tea is widely consumed in Guangxi. However, the documentation on the plants for herbal tea and their related health benefits is still limited. METHODS: An ethnobotanical survey was conducted in 52 villages and 21 traditional markets in Guangxi from 2016 to 2021. Semi-structured interviews, key informant interviews, and structured questionnaires were applied to obtain ethnobotanical information of herbal tea, in which 463 informants had participated. Relative frequency of citation (RFC) and cultural food significance index (CFSI) were used to evaluate the most culturally significant herbal tea plants, and informant consensus factor (ICF) was applied to assess the agreement among informants. RESULTS: This study recorded 155 herbal tea species belonging to 49 families. The most commonly used parts included leaf (27.61%), whole plant (22.09%), branch and leaf (19.02%), and flower (13.50%). The most frequent preparation method of herbal tea was decoction. Herbal tea was very popular in Guangxi, attributing to its therapeutic value, special odor, and good taste. There are 41 health benefits classified into eight categories. Among them, clearing heat was the most medicinal effects. Local people had high consistency in tonic, removing cold and cough, improving blood circulation, and clearing heat away. Based on CFSI values of each species, the most culturally significant herbal tea species were Siraitia grosvenorii (Swingle) C. Jeffrey ex A. M. Lu & Zhi Y. Zhang, Plantago asiatica L., Gynostemma pentaphyllum (Thunb.) Makino, Zingiber officinale Roscoe, Pholidota chinensis Lindl., and Morus alba L. CONCLUSION: Herbal tea is a valuable heritage that carries the local people's traditional knowledge, like health care and religious belief. The recorded herbal tea species in this study possess tremendous potential for local economic development in the future. Further research on efficacy evaluation and product development of herbal tea species is necessary.

UPLC-QTOF-MS-based metabolomics and chemometrics studies of geographically diverse Acer truncatum leaves: A traditional herbal tea in Northern China.

Traditionally in Northern China, Acer truncatum leaves (ATL) have been used as herbal tea, now consumed worldwide. Few studies have reported ATL metabolites from different areas and their correlation with the environment. Thus, metabolomic analyses were conducted on ATL collected from twelve locations throughout four environmental zones in Northern China to understand the phytochemical differences with regards to environmental conditions. Sixty-four compounds, mostly flavonoids (FLAs) and gallic acid-containing natural products (GANPs), were characterized, including 34 previously unreported constituents from A. truncatum. Twenty-two markers were useful to differentiate ATL from the four environmental zones. Humidity, temperature, and sunshine duration are the predominant factors affecting FLAs and GANPs levels. Sunshine duration was positively correlated with eriodictyol (r = 0.994, p < 0.01), and humidity negatively with epicatechin gallate (r = -0.960, p < 0.05). These findings provide insights into ATL phytochemistry, aiding cultivation of A. truncatum tea with higher potential health benefits.

Acer truncatum Bunge: A comprehensive review on ethnobotany, phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: Acer truncatum Bunge is a multifunctional plant in northern China. It has traditionally been used to prevent cardiovascular and cerebrovascular diseases and treat skin trauma by different linguistic groups including Mongolian, Tibetan, and Korean. Although research has verified that A. truncatum contains a variety of active ingredients, especially nervonic acid, an important component in delaying brain aging, to date no review has been made to compile its traditional use, phytochemistry, and pharmacology. AIMS OF THE REVIEW: This review aimed to update the traditional uses, phytochemistry, and pharmacology of A. truncatum, which expect to provide theoretical support for the future utilization as well as highlight the further investigation of this important plant. MATERIALS AND METHODS: The ethnobotanical, phytochemical, and pharmacological information related to A. truncatum from 1949 to March 2021 were collated by surveying the traditional medicinal books and ethnomedicinal publications and searching the online databases including Google Scholar, Sci Finder, Web of Science, Springer Link, PubMed, Wiley, China National Knowledge Infrastructure (CNKI), Baidu Scholar, and Wan Fang Database. RESULTS: A. truncatum has traditionally been used for medicinal, edible and ornamental purposes in northern China for many centuries. Different parts of the plant including leaves, fruits and bark, are mainly used as herbal medicine to treat hyperpiesia, hyperlipidemia, bruises, back pain, etc. A total of 288 compounds in A. truncatum, including polyphenols, organic acids or lipids, and biological volatile organic compounds were isolated or identified by phytochemical studies. Pharmacological research showed that A. truncatum has various bioactivities such as acetylcholinesterase inhibition, antibacterial, antioxidant, antitumor, and fatty acid synthase inhibition effects. CONCLUSION: A. truncatum has been used as a traditional herbal medicine for centuries in northern China. Polyphenols, organic acids, lipids and other compounds were isolated or identified from different parts of the plant. Most of the pharmacological activities of A. truncatum have been reported, which showed its potential in the development of new drugs or nutraceuticals. However, detailed information on the molecular mechanisms, metabolic activity, and toxicology of active components is limited. Further comprehensive research to evaluate the medicinal properties of A. truncatum will be necessary.

Metabolic profiling, in-situ spatial distribution, and biosynthetic pathway of functional metabolites in Dendrobium nobile stem revealed by combining UPLC-QTOF-MS with MALDI-TOF-MSI.

The stem of Dendrobium nobile Lindl. (Orchidaceae), called "Shihu" in traditional Chinese medicine, is a well-known medicinal and edible plant material in China. It is used as an antipyretic, analgesic, and tonic to nourish the stomach and Yin (i.e., to improve the production of body fluids). These therapeutic properties are attributed to its alkaloids, sesquiterpenoids, bibenzyls, fluorenones, and phenanthrenes. However, a comprehensive understanding of these metabolites and their spatial distribution in stems is lacking. In this study, ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was performed to obtain detailed metabolites information about D. nobile stems. Then, the spatial distributions of diverse metabolites, including alkaloids and sesquiterpenoids, were characterized and visualized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry imaging (MALDI-TOF-MSI). Based on the spatial and metabolic profiling data, sesquiterpene alkaloid dendrobine was chosen for the exhaustive study of a biosynthetic pathway in D. nobile. This is the first report on mass spectrometry imaging for Dendrobium species. As a result, critical bioactive metabolites such as 11 alkaloids, 10 sesquiterpenes, and 13 other metabolites were putatively identified and relatively quantified. The identified alkaloids were distributed in the parenchyma or vascular bundle, and sesquiterpenes were present in all regions of the stem with higher abundance in the vascular bundle and cuticle, or in the cuticle and epidermis. The biosynthetic pathway and accumulation pattern of dendrobine in D. nobile stem were also proposed. Our findings not only provided a critical methodology for the thorough understanding of physiological changes in metabolites and precise utilization of D. nobile stem, but also displayed an effective strategy for insight into the biosynthesis of bioactive metabolites in plants.

From Folk Taxonomy to Species Confirmation of Acorus (Acoraceae): Evidences Based on Phylogenetic and Metabolomic Analyses.

Plants in Acorus have been used as herbal medicine by various linguistic groups for thousands of years. Arguments of taxonomy of Acorus among scientists resulted in confusions and misuses of Acorus plants. The present study used different methods to investigate the classification of the genus, based on folk taxonomy. The relationships among Acorus species were revealed through phylogenetic analyses by constructing the Maximum Likelihood and Bayesian phylogenetic analyses based on sequences of two chloroplast regions (trnL-trnF and rbcL). All samples named with two so-called synonyms, Acorus macrospadiceus (Yamam.) F. N. Wei and Y. K. Li and Acorus tatarinowii Schott collected from different habitats, were clustered into separate groups, which revealed that they represented two independent species. Multivariate statistical analysis of metabolites from different Acorus populations were carried out based on UPLC-QTOF-MS data. Three independent analysis, principal component analysis, heat-map analysis, and hierarchical cluster analysis, showed that A. macrospadiceus and A. tatarinowii are different from two recognized species in the genus, A. calamus L. and A. gramineus Aiton. The results of phylogenetics and chemotaxonomy, together with morphological and ecological evidences, were consistent with traditional knowledge of local people related to Acorus taxa, which proved the significance of parataxonomy. Multiple evidences including morphological, ecological, folk taxonomic, phylogenetic, and chemical taxonomic results suggested that there are four species in the genus Acorus.

Variation of Microbiological and Biochemical Profiles of Laowo Dry-Cured Ham, an Indigenous Fermented Food, during Ripening by GC-TOF-MS and UPLC-QTOF-MS.

Fermented foods have unique microbiota and metabolomic profiles that can support dietary diversity, digestion, and gut health of consumers. Laowo ham (LWH) is an example of an indigenous fermented food from Southwestern China that has cultural, ecological, economic, and health significance to local communities. We carried out ethnobiological surveys coupled with metagenomic and metabolomic analyses using GC-TOF-MS and UPLC-QTOF-MS to elucidate the microbiota and metabolic profiles of LWH samples at different ripening stages. The results from high-throughput sequencing showed a total of 502 bacterial genera in LWH samples with 12 genera of bacteria and 6 genera of fungi identified as dominant groups. This is the first study to our knowledge to report the bacteria of Lentibacillus and Mesorhizobium along with fungi Eremascus and Xerochrysium on a fermented meat product. Findings further revealed that the metabolite profiles among LWH samples were significantly different. In total, 27 and 30 metabolites from GC-TOF-MS and UPLC-QTOF-MS analysis, respectively, were annotated as highly discriminative metabolites. Among the differential compounds, the relative contents of most amino acids showed the highest in the LWH sample ripened for two years, while some metabolites with potential therapeutic effects such as levetiracetam were the most abundant in the LWH sample ripened for three years. The correlation analysis indicated that the dominant microbes were closely related to differential metabolites, highlighting the importance of their functional characterization. Findings indicate that the consumption of LWH contributes to microbiological and chemical diversity of human diets as well as suggests efficacy of combining GC-MS and LC-MS to study the metabolites in dry-cured meat products.

Three new compounds with nitric oxide inhibitory activity from Tirpitzia sinensis, an ethnomedicinal plant from Southwest China.

The medicinal plant Tirpitzia sinensis has been used by the Zhuang ethnic people in mountainous areas of Southwest China to stop bleeding, invigorate blood circulation, and treat inflammation and wounds. In order to further explore its traditional medicinal uses, the phytochemical constituents of this species were examined. Three new compounds, the lignan tirpitzin (1), the flavonoid tirpitzoside (2), and the furan-glycoside tirpitziol (3), along with five known compounds were isolated from the aerial part of T. sinensis for the first time. The structures of these compounds were elucidated by 1D and 2D NMR, LC/MS, IR spectrometric methods and compared with published data. The results of an in silico pharmacophore-based analysis showed potential targets of the new compounds, including ERBB2, IRAK4, LCK, JAK2, MAPK14, and MMP-12. These targets suggested that 1-3 may be involved with wound-healing and/or inflammation, leading to an in vitro assay of nitric oxide (NO) inhibition assays with lipopolysaccharide-induced BV-2 cells. All three new compounds displayed moderate NO inhibitory activity with the IC50 values of 14.97 ± 0.87, 26.63 ± 1.32, and 17.09 ± 2.3 µM, respectively.

Metabolic Profiling of Different Parts of Acer truncatum from the Mongolian Plateau Using UPLC-QTOF-MS with Comparative Bioactivity Assays.

Acer truncatum is an important ornamental, edible, and medicinal plant resource in China. Previous phytochemical research has focused on the leaf (AL) due to its long history as a tea for health. Other parts such as the branch (ABr), bark (ABa), fruit (AF), and root (AR) have drawn little attention regarding their metabolites and bioactivities. The strategy of an in-house chemical library combined with Progenesis QI informatics platform was applied to characterize the metabolites. A total of 98 compounds were characterized or tentatively identified, including 63 compounds reported from this species for the first time. Principal component analysis showed the close clustering of ABr, ABa, and AR, indicating that they share similar chemical components, while AL and AF clustered more distantly. By multiple orthogonal partial least-squares discriminant analyses (OPLS-DA), 52 compounds were identified as potential marker compounds differentiating these different plant parts. The variable influence on projection score from OPLS-DA revealed that catechin, procyanidins B2 or B3, and procyanidins C1 or C2 are the significant metabolites in ABa extracts, which likely contribute to its antioxidant and cytotoxic activities.

Gaultheria Ethnobotany and Bioactivity: Blueberry Relatives with Anti-inflammatory, Antioxidant, and Anticancer Constituents.

Gaultheria, a genus belonging to the Ericaceae family, is typically a shrub that produces berries, and closely resembles the blueberry genus Vaccinium. Gaultheria species are used worldwide especially as food and medicine in China. Certain Gaultheria species are biologically active, as antioxidants, anti-inflammatories, and cytotoxic agents. Through literature searches and field surveys, the results of ethnobotanical uses, especially in China, as well as in vitro and in vivo studies are reviewed critically. This review examines the chemistry and bioactivity of this under-studied plant genus, and thus lays the groundwork for its future development for human health.

Deep sequencing and transcriptome analyses to identify genes involved in secoiridoid biosynthesis in the Tibetan medicinal plant Swertia mussotii.

Swertia mussotii Franch. is an important traditional Tibetan medicinal plant with pharmacological properties effective in the treatment of various ailments including hepatitis. Secoiridoids are the major bioactive compounds in S. mussotii. To better understand the secoiridoid biosynthesis pathway, we generated transcriptome sequences from the root, leaf, stem, and flower tissues, and performed de novo sequence assembly, yielding 98,613 unique transcripts with an N50 of 1,085 bp. Putative functions could be assigned to 35,029 transcripts (35.52%) based on BLAST searches against annotation databases including GO and KEGG. The expression profiles of 39 candidate transcripts encoding the key enzymes for secoiridoid biosynthesis were examined in different S. mussotii tissues, validated by qRT-PCR, and compared with the homologous genes from S. japonica, a species in the same family, unveiling the gene expression, regulation, and conservation of the pathway. The examination of the accumulated levels of three bioactive compounds, sweroside, swertiamarin, and gentiopicroside, revealed their considerable variations in different tissues, with no significant correlation with the expression profiles of key genes in the pathway, suggesting complex biological behaviours in the coordination of metabolite biosynthesis and accumulation. The genomic dataset and analyses presented here lay the foundation for further research on this important medicinal plant.

Important poisonous plants in tibetan ethnomedicine.

Tibetan ethnomedicine is famous worldwide, both for its high effectiveness and unique cultural background. Many poisonous plants have been widely used to treat disorders in the Tibetan medicinal system. In the present review article, some representative poisonous plant species are introduced in terms of their significance in traditional Tibetan medicinal practices. They are Aconitum pendulum, Strychnos nux-vomica, Datura stramonium and Anisodus tanguticus, for which the toxic chemical constituents, bioactivities and pharmacological functions are reviewed herein. The most important toxins include aconitine, strychnine, scopolamine, and anisodamine. These toxic plants are still currently in use for pain-reduction and other purposes by Tibetan healers after processing.

Prospecting for bioactive constituents from traditional medicinal plants through ethnobotanical approaches.

Pharmacologically active constituents from traditional medicinal plants have received great attention as sources of novel agents, pharmaceutical intermediates, and chemical entities for synthetic or semisynthetic drugs due to their potent pharmacological activities, low toxicity, and economic viability. Numerous components have been isolated from traditional medicinal plants, including alkaloids, flavonoids, and terpenoids, and clinical and experimental studies suggested that these components have useful pharmacological properties such as antiinfectious, antioxidative, and antiinflammatory effects. In this review, modern ethnobotanical approaches to explore folk medicinal plants as candidates for drug discovery with the greatest possibility of success are discussed. Determining the bioactive mechanisms and tracing structure-activity relationships will promote the discovery of new drugs and pharmacological agents.