Suitable DNA Barcoding for Identification and Supervision of Piper kadsura in Chinese Medicine Markets

The research of river basin ecological compensation based on water emissions trading mechanism

By integrating the successful case of the European Union emissions trading system, this study proposes a water emissions trading system, a novel method of reducing water pollution. Assuming that upstream governments allocate initial quotas to upstream businesses as the compensation standard, this approach defines the foundational principles of market trading mechanisms and establishes a robust watershed ecological compensation model to address challenges in water pollution prevention. To be specific, the government establishes a reasonable initial quota for upstream enterprises, which can be used to limit the emissions of upstream pollution. When enterprises exceed their allocated emissions quota, they face financial penalties. Conversely, these emissions rights can be transformed into profitable assets by participating in the trading market as a form of ecological compensation. Numerical simulations demonstrate that various pollutant emissions from upstream businesses will have various effects on the profits of other businesses. Businesses in the upstream region received reimbursement from the assigned emission rights through the market mechanism, demonstrating that ecological compensation for the watershed can be achieved through the market mechanism. This novel market trading system aims at controlling emissions management from the perspectives of individual enterprises and ultimately optimizing the aquatic environment.

Galgravin Isolated from Piper kadsura Ameliorates Lipopolysaccharide (LPS)-Induced Endotoxemia in Mice

Sepsis results from uncontrolled inflammation, characterized by cytokine storm and immunoparalysis. To assess whether galgravin, a natural lignan isolated from Piper kadsura, can be used to treat sepsis, models of bacterial lipopolysaccharide (LPS)-activated macrophages and LPS-induced endotoxemia mice were used. Galgravin suppressed NF-κB activation in LPS-activated RAW 264.7 macrophages without causing significant cytotoxicity, in which proinflammatory molecules like TNF-α, IL-6, iNOS, and COX-2 were downregulated. In addition, the expression of TNF-α and IL-6 was also suppressed by galgravin in LPS-activated murine bone marrow-derived macrophages. Moreover, galgravin significantly downregulated the mRNA expression of TNF-α, IL-6, and iNOS in the lungs and decreased TNF-α and IL-6 in the serum and IL-6 in the bronchoalveolar lavage fluid of LPS-challenged mice. The COX-2 expression in tissues, including the lung, liver, and kidney, as well as the lung alveolar hemorrhage, was also reduced by galgravin. The present study reveals the anti-inflammatory effects of galgravin in mouse models and implies its potential application in inflammation diseases.

Advancements and future prospective of DNA barcodes in the herbal drug industry

Ethnopharmacological relevance: The past couple of decades have witnessed the global resurgence of medicinal plants in the field of herbal-based health care. Increased consumption of medicinal plants and their derivative products is the major cause of the adulteration issues in herbal industries. As a result, the quality of herbal products is affected by spurious and unauthorized raw materials. Recent development in molecular plant identification using DNA barcodes has become a robust methodology to identify and authenticate the adulterants in herbal samples. Hence, rapid and accurate identification of medicinal plants is the key to success for the herbal industry. Aim of the study: This paper provides a comprehensive review of the application of DNA barcoding and advanced technologies that have emerged over the past 10 years related to medicinal plant identification and authentication and the future prospects of this technology. Materials and methods: Information on DNA barcodes was compiled from scientific databases (Google Scholar, Web of Science, SciFinder and PubMed). Additional information was obtained from books, Ph.D. thesis and MSc. Dissertations. Results: Working out an appropriate DNA barcode for plants is challenging; the single locus-based DNA barcodes (rbcL, ITS, ITS2, matK, rpoB, rpoC, trnH-psbA) to multi-locus DNA barcodes have become the successful species-level identification among herbal plants. Additionally, multi-loci have become efficient in the authentication of herbal products. Emerging advances in DNA barcoding and related technologies such as next-generation sequencing, high-resolution melting curve analysis, meta barcodes and mini barcodes have paved the way for successful herbal plant/samples identification. Conclusion: DNA barcoding needs to be employed together with other techniques to check and rationally and effectively quality control the herbal drugs. It is suggested that DNA barcoding techniques combined with metabolomics, transcriptomics, and proteomics could authenticate the herbal products. The invention of simple, cost-effective and improved DNA barcoding techniques to identify herbal drugs and their associated products of medicinal value in a fool-proof manner will be the future thrust of Pharmacopoeial monograph development for herbal drugs.

Conventional and molecular pharmacognostic characters integrated with chemical profiles of five Piper plants in the Thai herbal pharmacopoeia and their admixture/adulteration/substitution situations in Thailand

The morphological and microscopy were combined with DNA-barcoding, together with rapid TLC for the characterization of Piper betle (PB), P. nigrum (PN), P. retrofractum (PR), P. sarmentosum (PS), and P. wallichii (PW), five medicinal Piper plants announced in the Thai Herbal Pharmacopoeia (THP). The authentic plants collected from various locations and voucher Piper products bought from commercial sites in Thailand were studied. The reproductive parts of authentic plants were subjected to ensure their morphological characters. Using sequencing analysis and genetic divergence for analyzing discriminatory performance, ITS2 was selected from eight candidate DNA markers to authenticate the origin of Piper crude drugs together with microscopic and TLC profiles for examining their characters, admixtures, adulterants, and substituents. PB and PR exhibited unique characters of the species, with no admixture, adulteration, and substitution. PN showed no variable characters of morphology and genetics. However, the microscopy could illustrate some commercial products of PN sold in Thailand have been adulterated with rice starch and roasted rice. In the herbal trade, PS has been sold in the form of mixed leaf, root, and stem more than the isolated part, but there is no variable character of the species. PW has shown more than one character of species explained by microscopic, chemical components, and genetic data. In conclusion, the conventional and molecular pharmacognostic data combined with chemical profile of authentic five Piper plants could be applied to indicate the plant origin and clarify the situations of admixture, adulteration, and substitution of the commercial Piper products launched in Thailand.

The specific DNA barcodes based on chloroplast genes for species identification of Theaceae plants

More than 600 species in over 40 genera have been identified in family Theaceae worldwide. The accurate identification of Theaceae plants can ensure the market economic order, and it plays a vital role in achieving the sustainable utilization of germplasm resources. DNA barcoding, one of the most potential species identification technologies at present, has advanced in the rapid, accurate and repetitive discrimination of species. In this study, matK + ndhF + ycf1 was observed as the optimal combined candidate gene sequence of DNA barcodes by analyzing genetic information of four single chloroplast DNA sequences, including matK, rbcL, ndhF and ycf1, as well as six combined gene sequences. Subsequently, the experiments were performed on phylogenetic analysis based on genetic distance to study the phylogenetic relationship of Theaceae plants and evaluate the species identification accuracy of matK + ndhF + ycf1. Lastly, the species-specific DNA barcodes were designed by searching the variable sites (one type of single nucleotide polymorphism sites) for the accurate identification of Camellia amplexicaulis, Franklinia alatamaha, Gordonia brandegeei and Stewartia micrantha. The previous methods of screening and testing candidate gene sequences were optimized, and innovation was made in the above methods. The process of making visual DNA barcodes was standardized. Besides, DNA barcoding technology increased the accuracy of species identification and DNA barcoding was analyzed in accordance with the theories of population genetics (e.g., neutral theory of molecular evolution). The results of the study will lay a basis for the identification and protection of Theaceae species and germplasm resources.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-022-01175-7.

Evaluation of DNA markers for molecular identification of three Piper species from Brazilian Atlantic Rainforest

Piper is one of two large genera in the Piperaceae, and with ca. 2600 species, is one of the largest plant genera in the world. Species delimitation and evaluation of genetic diversity among populations are important requisites for conservation and adequate exploitation of economically important species. DNA barcoding has been used as a powerful tool and a practical method for species characterization and delimitation. The present work aims to evaluate molecular markers for barcoding three Piper species native to Brazil: P. gaudichaudianum (“jaborandi” or “pariparoba”), P. malacophyllum (“pariparoba-murta”) and P. regnellii (“caapeba” or “pariparoba”). A reference DNA barcode library was developed using sequences of three candidate regions: ITS2, trnH-psbA and rbcL. Transferability of the microsatellite (SSR) primers Psol 3, Psol 6 and Psol 10, designed originally for Piper solmsianum, to the three Piper species was also evaluated. The discriminatory power of the markers was based on the determination of inter- and intraspecific distances, phylogenetic reconstruction, and clustering analysis, as well as BLASTn comparison. Sequences of ITS2 enabled efficient species identification by means of the BLASTn procedure. Based on these sequences, intraspecific divergence was lower than interspecific variation. Maximum Parsimony analyses based on ITS2 sequences provided three resolved clades, each corresponding to one of the three analysed species. Sequences of trnH-psbA and rbcL had lower discriminatory value. Analyses combining sequences of these regions were less effective toward the attainment of resolved and strongly supported clades of all species. In summary, robustly supported clades of P. regnellii were obtained in most of the analyses, based either on isolated or combined sequences. The SSRs primers Psol 3, Psol 6 and Psol 10 were shown to be transferable to P. gaudichaudianum and P. regnellii, but not to P. malacophyllum. Preliminary cluster analyses based on the polymorphism of the amplified products suggested that Psol 3 has lower potential than Psol 6 and Psol 10 for discrimination of Piper species.

DNA barcodes for the identification of Stephania (Menispermaceae) species

Stephania is a medicinal plants-rich genus of Menispermaceae. However, the identification of morphologically-similar species in Stephania is difficult using the currently reported methods. The indiscriminate overexploitation of Stephania plants has resulted in clinical misuse and endangerment of many species, which necessitates the development of an efficient and reliable method for species authentication. Therefore, six candidate DNA barcode sequences (ITS, ITS2, psbA-trnH, matK, rbcL, and trnL-F) were tested for their capacity to identify Stephania species. The barcodes were analyzed either as a single region or in combination by tree-based [neighbor-joining (NJ) and Bayesian inference (BI)], distance-based (PWG-distance), and sequence similarity-based (TaxonDNA) methods. Amplification and sequencing success rates were 100% for all six candidate barcodes. A comparison of six barcode regions showed that ITS exhibited the highest number of variable and informative sites (182/179), followed by psbA-trnH (173/162). DNA barcoding gap assessment showed that interspecific distances of the six barcodes were greater than intraspecific distances. The identification results showed that species discrimination rates of combination barcodes were higher than those of single-region barcodes. Based on best match and best close match methods, the ITS+psbA-trnH combination exhibited the highest discrimination power (93.93%). Further, all Stephania species could be resolved in the phylogenetic trees based on ITS+psbA-trnH (NJ, BI). This study demonstrates that DNA barcoding is an efficient method to identify Stephania species and recommends that the ITS+psbA-trnH combination is the best DNA barcode for the identification of Stephania species.

Integrated approach for identifying and evaluating the quality of Marsdenia tenacissima in the medicine market

The accurate identification and quality evaluation of herbal medical plants is highly necessary to ensure their safety and efficacy. In present study, a new strategy combining DNA barcoding techniques with thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) was proposed to facilitate the identification and quality control of M. tenacissima. In present work, the internal transcribed spacer 2 (ITS2) barcode was successfully used to identify 58 M. tenacissima samples and its adulterants. TLC successfully identified the other three M. tenacissima samples that failed to produce ITS2 regions. An adulterant was found in all the 62 samples. Moreover, the content of active medicinal ingredients is important for herbal plants quality. The content of tenacissoside H (TS-H) of M. tenacissima samples was determined by HPLC to range from 0.39% to 1.09%, which meets the criterion of the Chinese Pharmacopoeia. Thus, DNA barcoding coupled with TLC and HPLC is very promising to identify and evaluate the quality of M. tenacissima in the medicine market.

Species Adulteration in the Herbal Trade: Causes, Consequences and Mitigation

The global economy of the international trade of herbal products has been increasing by 15% annually, with the raw material for most herbal products being sourced from South and Southeast Asian countries. In India, of the 8000 species of medicinal plants harvested from the wild, approximately 960 are in the active trade. With increasing international trade in herbal medicinal products, there is also increasing concern about the widespread adulteration and species admixtures in the raw herbal trade. The adverse consequences of such species adulteration on the health and safety of consumers have only recently begun to be recognised and documented. We provide a comprehensive review of the nature and magnitude of species adulteration in the raw herbal trade, and identify the underlying drivers that might lead to such adulteration. We also discuss the possible biological and chemical equivalence of species that are used as adulterants and substitutes, and the consequences thereof to consumer health and safety, and propose a framework for the development of a herbal trade authentication service that can help regulate the herbal trade market.

Inspecting the True Identity of Herbal Materials from Cynanchum Using ITS2 Barcode

Cynanchum is a large genus with some important medicinal species in China. The medicinal species in Cynanchum are easily confused, leading to potential safety risks. In this study, the internal transcribed spacer 2 (ITS2) barcode was used to discriminate the medicinal plants in Cynanchum. The identifying capability of ITS2 was assessed using the specific genetic divergence, BLAST1, neighbor-joining (NJ) tree, maximum-likelihood (ML) tree, and single-nucleotide polymorphism (SNP) methods. Results indicated that the intra-specific genetic divergences of Cynanchum species were lower than their inter-specific genetic divergences. Of the 87 samples from 17 species, ITS2 showed a high identification efficiency of 90.8 and 87.4% at the species level through BLAST1 and the nearest distance methods. NJ tree and ML tree also demonstrated the suitability of ITS2 to differentiate Cynanchum species. Meanwhile, a stable SNP was found, and it could accurately authenticate Cynanchum paniculatum and Cynanchum atratum. Furthermore, we collected 64 commercial samples from three commonly used herbal medicines and evaluated the capability of ITS2 to survey their authentication. Of these samples, Cynanchi Atrati Radix et Rhizoma (Baiwei) showed a potential safety problem, and all the 11 test samples were adulterants. In conclusion, ITS2 can distinguish medicinal species in Cynanchum effectively, and its application could greatly improve the identification efficiency and accuracy of commercial herbal medicines in this genus.

Barcode ITS2: a useful tool for identifying Trachelospermum jasminoides and a good monitor for medicine market

Trachelospermum jasminoides is commonly used in traditional Chinese medicine. However, the use of the plant's local alternatives is frequent, causing potential clinical problems. The T. jasminoides sold in the medicine market is commonly dried and sliced, making traditional identification methods difficult. In this study, the ITS2 region was evaluated on 127 sequences representing T. jasminoides and its local alternatives according to PCR and sequencing rates, intra- and inter-specific divergences, secondary structure, and discrimination capacity. Results indicated the 100% success rates of PCR and sequencing and the obvious presence of a barcoding gap. Results of BLAST 1, nearest distance and neighbor-joining tree methods showed that barcode ITS2 could successfully identify all the texted samples. The secondary structures of the ITS2 region provided another dimensionality for species identification. Two-dimensional images were obtained for better and easier identification. Previous studies on DNA barcoding concentrated more on the same family, genus, or species. However, an ideal barcode should be variable enough to identify closely related species. Meanwhile, the barcodes should also be conservative in identifying distantly related species. This study highlights the application of barcode ITS2 in solving practical problems in the distantly related local alternatives of medical plants.