Ethnopharmacology, biological activities and chemical compounds of Canarium strictum: An important resin-yielding medicinal tree in India.

The resin of Canarium strictum Roxb. is used for rheumatism and asthma; the bark is used as a mosquito repellent. The major compounds in the resin are triterpenoids, but as no studies have been performed on the bark, this study investigated this economically important resource. Ten folk healers were interviewed about their medicinal uses of C. strictum. Resin and bark were extracted with dichloromethane followed by methanol using accelerated solvent extraction. The extracts were fractionated using different chromatographic methods, and isolated compounds were identified by NMR spectroscopy and GC-MS. Resin and bark extracts were investigated for DPPH radical scavenging, 15-lipoxygenase inhibition, effects on nitric oxide (NO) production in LPS-activated dendritic D2SC/I cells and toxicity against Artemia salina nauplii. Traditional healers used resin to treat colds, airway afflictions and rheumatoid arthritis. α-Amyrin and ß-amyrin were identified as the major constituents in the dichloromethane resin extract. From the stem bark, procyanidins, gallic acid, methyl gallate, scopoletin, 3,3'-di-O-methylellagic acid 4-O-α-arabinofuranoside and elephantorrhizol (3,3',4',5,6,7,8-heptahydroxyflavan) were isolated and identified. By GC-MS, α-amyrin and ß-amyrin and their acetates, lupeol, and taraxasterol were identified. Radical scavenging, 15-lipoxygenase inhibitory activity and inhibition of NO production was observed from resin and bark extracts, and no toxicity towards Artemia salina nauplii was found. Triterpenoids and procyanidins are the major compounds in C. strictum resin and stem bark, respectively. The high content of triterpenoids might contribute to anti-inflammatory effects and give a rationale for the widespread usage of the resin in India.

DNA Metabarcoding Authentication of Ayurvedic Herbal Products on the European Market Raises Concerns of Quality and Fidelity.

Ayurveda is one of the oldest systems of medicine in the world, but the growing commercial interest in Ayurveda based products has increased the incentive for adulteration and substitution within this herbal market. Fraudulent practices such as the use of undeclared fillers and use of other species of inferior quality is driven both by the increased as well as insufficient supply capacity of especially wild plant species. Developing novel strategies to exhaustively assess and monitor both the quality of raw materials and final marketed herbal products is a challenge in herbal pharmacovigilance. Seventy-nine Ayurvedic herbal products sold as tablets, capsules, powders, and extracts were randomly purchased via e-commerce and pharmacies across Europe, and DNA metabarcoding was used to assess the ability of this method to authenticate these products. Our analysis reveals that only two out of 12 single ingredient products contained only one species as labeled, eight out of 27 multiple ingredient products contained none of the species listed on the label, and the remaining 19 products contained 1 to 5 of the species listed on the label along with many other species not specified on the label. The fidelity for single ingredient products was 67%, the overall ingredient fidelity for multi ingredient products was 21%, and for all products 24%. The low level of fidelity raises concerns about the reliability of the products, and detection of threatened species raises further concerns about illegal plant trade. The study highlights the necessity for quality control of the marketed herbal products and shows that DNA metabarcoding is an effective analytical approach to authenticate complex multi ingredient herbal products. However, effort needs to be done to standardize the protocols for DNA metabarcoding before this approach can be implemented as routine analytical approaches for plant identification, and approved for use in regulated procedures.

Authentication of Garcinia fruits and food supplements using DNA barcoding and NMR spectroscopy.

Garcinia L. (Clusiaceae) fruits are a rich source of (-)-hydroxycitric acid, and this has gained considerable attention as an anti-obesity agent and a popular weight loss food supplement. In this study, we assessed adulteration of morphologically similar samples of Garcinia using DNA barcoding, and used NMR to quantify the content of (-)-hydroxycitric acid and (-)-hydroxycitric acid lactone in raw herbal drugs and Garcinia food supplements. DNA barcoding revealed that mostly G. gummi-gutta (previously known as G. cambogia) and G. indica were traded in Indian herbal markets, and there was no adulteration. The content of (-)-hydroxycitric acid and (-)-hydroxycitric acid lactone in the two species varied from 1.7% to 16.3%, and 3.5% to 20.7% respectively. Analysis of ten Garcinia food supplements revealed a large variation in the content of (-)-hydroxycitric acid, from 29 mg (4.6%) to 289 mg (50.6%) content per capsule or tablet. Only one product contained quantifiable amounts of (-)-hydroxycitric acid lactone. Furthermore the study demonstrates that DNA barcoding and NMR could be effectively used as a regulatory tool to authenticate Garcinia fruit rinds and food supplements.

Ethnobotany of dioecious species: Traditional knowledge on dioecious plants in India.

ETHNOPHARMACOLOGICAL RELEVANCE: More than 15,000 angiosperm species are dioecious, i.e., having distinct male and female individual plants. The allocation of resources between male and female plants is different, and also variation in secondary metabolites and sex-biased herbivory is reported among dioecious plants. However, little is known about the ethnobotany of dioecious species and whether preferences exist for a specific gender, e.g., in food, medicine or timber. AIM OF THE STUDY: The aim of this study was: 1) to study whether Indian folk healers have preference for plant genders, and to document their knowledge and use of dioecious species; 2) to understand the concept of plant gender in Indian systems of medicine and folk medicine, and whether Ayurvedic literature includes any references to gender preference. MATERIALS AND METHODS: Lists of dioecious plants used in Indian systems of medicine and folk medicine were compiled. Ethnobotanical data was collected on perceptions and awareness of dioecious plants, and preferences of use for specific genders of dioecious species using semi-structured interviews with folk healers in Tamil Nadu, India. In addition, twenty Ayurvedic doctors were interviewed to gain insight into the concept of plant gender in Ayurveda. RESULTS: Indian systems of medicine contain 5-7% dioecious species, and this estimate is congruent with the number of dioecious species in flowering plants in general. Informants recognized the phenomenon of dioecy in 31 out of 40 species, and reported gender preferences for 13 species with respect to uses as timber, food and medicine. Among informants different plant traits such as plant size, fruit size, and visibility of fruits determines the perception of a plant being a male or female. Ayurvedic classical literature provides no straightforward evidence on gender preferences in preparation of medicines or treatment of illness, however it contains details about reproductive morphology and sexual differentiation of plants. CONCLUSIONS: A knowledge gap exists in ethnobotanical and ethnopharmacological literature on traditional knowledge of dioecious plants. From this explorative study it is evident that people have traditional knowledge on plant gender and preferential usages towards one gender. Based on this, we propose that researchers conducting ethnobotanical and ethnopharmacological studies should consider documenting traditional knowledge on sexual systems of plants, and test the existence of gender specific usages in their conceptual framework and hypothesis testing. Incorporating such concepts could provide new dimensions of scientific knowledge with potential implications to conservation biology, chemical ecology, ethnoecology and drug discovery.

Assessing product adulteration in natural health products for laxative yielding plants, Cassia, Senna, and Chamaecrista, in Southern India using DNA barcoding.

Medicinal plants such as Cassia, Senna, and Chamaecrista (belonging to the family Fabaceae) are well known for their laxative properties. They are extensively used within indigenous health care systems in India and several other countries. India exports over 5000 metric tonnes per year of these specific herbal products, and the demand for natural health product market is growing at approximately 10-15% annually. The raw plant material used as active ingredients is almost exclusively sourced from wild populations. Consequently, it is widely suspected that the commercial herbal products claiming to contain these species may be adulterated or contaminated. In this study, we have attempted to assess product authentication and the extent of adulteration in the herbal trade of these species using DNA barcoding. Our method includes four common DNA barcode regions: ITS, matK, rbcL, and psbA-trnH. Analysis of market samples revealed considerable adulteration of herbal products: 50% in the case of Senna auriculata, 37% in Senna tora, and 8% in Senna alexandrina. All herbal products containing Cassia fistula were authentic, while the species under the genus Chamaecrista were not in trade. Our results confirm the suspicion that there is rampant herbal product adulteration in Indian markets. DNA barcodes such as that demonstrated in this study could be effectively used as a regulatory tool to control the adulteration of herbal products and contribute to restoring quality assurance and consumer confidence in natural health products.

nrDNA ITS sequence based SCAR marker to authenticate Aconitum heterophyllum and Cyperus rotundus in Ayurvedic raw drug source and prepared herbal products.

To authenticate Ayurvedic medicinal plants Ativisha (Aconitum heterophyllum) and Musta (Cyperus rotundus) at the raw drug source and in prepared herbal products, nrDNA ITS sequence based SCAR markers were designed and validated spp.-specific SCAR primers gave amplicon of 415 bp and 134 bp, respectively, in authentic species. The SCAR primers (Cyr-FP and Cyr-RP) could identify tissue sample containing 750 µg to 4.76 mg/100mg of Musta in complex mixtures of DNA extracted from commercial herbal drugs. Ativisha could not be identified through SCAR markers suggesting that authentic species may not been used to prepare herbal drugs despite its being labelled as one of the ingredients in formulations. Analysis of individual tubers of Ativisha and Musta assures the presence of admixtures in raw drug trade of Ativisha, indicates the need to monitor the basic raw material supply and concludes, supplying plant materials through cultivation to manufacturing industries can minimize the risks of adulteration.