Rapid Authentication of the Herbal Medicine Plant Species Aralia continentalis Kitag. and Angelica biserrata C.Q. Yuan and R.H. Shan Using ITS2 Sequences and Multiplex-SCAR Markers

A comprehensive analysis integrating phenotypic assessment uncovering thornless cultivar lineages in Aralia elata

Aralia elata is an Araliaceae woody plant species found in Northeastern Asia. To understand how genetic pools are distributed for A.elata clones, we were to analyze the population structure of A.elata cultivars and identify how these are correlated with thorn-related phenotype which determines the utility of A.elata. We found that the de novo assembled genome of 'Yeongchun' shared major genomic compartments with the public A.elata genome assembled from the wild-type from China. To identify the population structure of the 32 Korean and Japanese cultivars, we identified 44 SSR markers and revealed three main sub-clusters using ΔK analysis with one isolated cultivar. Machine-learning based clustering with thorn-related phenotype correlated moderately with population structure based on SSR analysis suggested multi-layered genetic regulation of thorn-related phenotypes. Thus, we revealed genetic lineage of A.elata and uncovered isolated cultivar which can provide new genetic material for further breeding.

Assembly and comparative analysis of the first complete mitochondrial genome of a traditional Chinese medicine Angelica biserrata (Shan et Yuan) Yuan et Shan

Duhuo, a member of the Angelica family, is widely used to treat ailments such as rheumatic pain. It possesses a diverse array of bioactivities, including anti-tumor, anti-inflammatory, and analgesic properties, as recent pharmacological research has revealed. Nevertheless, the mtDNA of Angelica species remains relatively unexplored. To address this gap, we sequenced and assembled the mtDNA of A. biserrata to shed light on its genetic mechanisms and evolutionary pathways. Our investigation indicated a distinctive multi-branched conformation in the A. biserrata mtDNA. A comprehensive analysis of protein-coding sequences (PCGs) across six closely related species revealed the presence of 11 shared genes in their mitochondrial genomes. Intriguingly, positive selection emerged as a significant factor in the evolution of the atp4, matR, nad3, and nad7 genes. In addition, our data highlighted a recurring trend of homologous fragment migration between chloroplast and mitochondrial organelles. We identified 13 homologous fragments spanning both chloroplast and mitochondrial genomes. The phylogenetic tree established a close relationship between A. biserrata and Saposhnikovia divaricata. To sum up, our research would contribute to the application of population genetics and evolutionary studies in the genus Acanthopanax and other genera in the Araliaceae family.

Genome skimming as an efficient tool for authenticating commercial products of the pharmaceutically important Paris yunnanensis (Melanthiaceae)

BACKGROUND

Paris yunnanensis (Melanthiaceae) is a traditional Chinese medicinal plant of significant pharmaceutical importance. Due to previous taxonomic confusion, a congeneric species, Paris liiana, has been mistaken for P. yunnanensis and cultivated on a large scale, leading to the mixing of commercial products (i.e., seedlings and processed rhizomes) of P. yunnanensis with those of P. liiana. This may have adverse effects on quality control in the standardization of P. yunnanensis productions. As the lack of PCR amplifiable genomic DNA within processed rhizomes is an intractable obstacle to the authentication of P. yunnanensis products using PCR-based diagnostic tools, this study aimed to develop a PCR-free method to authenticate commercial P. yunnanensis products, by applying genome skimming to generate complete plastomes and nrDNA arrays for use as the molecular tags.

RESULTS

Based on a dense intraspecies sampling of P. liiana and P. yunnanensis, the robustness of the proposed authentication systems was evaluated by phylogenetic inferences and experimental authentication of commercial seedling and processed rhizome samples. The results indicate that the genetic criteria of both complete plastomes and nrDNA arrays were consistent with the species boundaries to achieve accurate discrimination of P. yunnanensis and P. liinna. Owing to its desirable accuracy and sensitivity, genome skimming can serve as an effective and sensitive tool for monitoring and controlling the trade of P. yunnanensis products.

CONCLUSION

This study provides a new way to solve the long-standing problem of the molecular authentication of processed plant products due to the lack of PCR amplifiable genomic DNA. The proposed authentication system will support quality control in the standardization of P. yunnanensis products in cultivation and drug production. This study also provides molecular evidence to clarify the long-standing taxonomic confusion regarding the species delimitation of P. yunnanensis, which will contribute to the rational exploration and conservation of the species.

An evaluation of the qualitative superiority of the Mongolian medicinal herb hurdan-tsagaan (Platycodi Radix) from five different geographic origins based on anti-inflammatory effects

ETHNOPHARMACOLOGICAL RELEVANCE

The contents and types of the active compounds in medicinal herbs depend greatly on their extraction methods, sources of origin and the modes of cultivation. Platycodon grandiflorus (Jacq.) A.DC. is an ethnic medicinal herb widely cultivated in China, and its dried root, Platycodi Radix (PR), is an important ingredient in herbal formulae for attenuating lung issues in Mongolian medical practice. However, research evaluating the superiority of PR based on harvesting regions is relatively limited.

AIM

This study aimed to evaluate the qualitative superiority of PR from different regions based on anti-inflammatory effect.

MATERIALS AND METHODS

A total of three commercial PR samples were obtained from Anguo, Bozhou and Shangluo, and two wild samples were obtained from Chifeng and Hinggan. PR extract (PRE) was prepared by water distillation, and platycodin D content in the extract was examined by HPLC-UVD. An optimal dose of PRE was administered to BALB/c mice with S. pneumoniae pneumonia, and IL-10 and TNF-α levels in lung tissue were examined by ELISA. HepG2 cells were treated with PRE, and an analysis of differentially expressed gene and functional enrichment was performed using an HTS² assay.

RESULTS

The contents of moisture, total ash, crude extract and platycodin D in the raw roots met the quality control requirements outlined in the Chinese Pharmacopoeia (2020 edition). The platycodin D content in the aqueous extract of the roots in descending order was 24.16% in PRE_Shangluo, 22.91% in PRE_Hinggan, 21.41% in PRE_Bozhou, 17.8% in PRE_Chifeng and 15.92% in PRE_Anguo. Furthermore, administration of PREs at an optimal dose of 2.0 g/kg resulted in some anti-inflammatory effect in mice with Streptococcus pneumoniae pneumonia, among which PRE_Shangluo administration exhibited a more obvious anti-inflammatory impact as shown by a significant decrease in the plasma white cell count (p < 0.05) and IL-10 level elevation and TNF-α reduction in lung tissue (p < 0.05) after treatment. In HepG2 cells treated with 100 μg/ml of each PRE, PRE_Hinggan and PRE_Shangluo resulted in significant differential expression of genes such as nuclear factor kappa B subunit 1 (NFKB1) and significant enrichment of pathways involved in the immune system, such as PI3K-Akt, MAPK and NF-kappa B signaling pathways.

CONCLUSIONS

In this study, based on the anti-inflammatory effect, the quality of PR of Shangluo origin was superior to that of PR from the other four regions.

Rapid Identification of Paeoniae Radix and Moutan Radicis Cortex Using a SCAR Marker-Based Conventional PCR Assay

Paeoniae Radix is a herbal medicine prepared from the dried roots of Paeonia lactiflora, P. anomala subsp. veitchii, and P. japonica. Although the herbal medicines prepared from these species are morphologically similar, they have different pharmacological effects depending on how they are processed. In addition, P. japonica is more expensive than other Paeonia spp. in the Korean herbal market. Although there is a clear difference between the Korean and Chinese pharmacopeias of Paeoniae Radix, the processed roots of P. lactiflora and P. anomala subsp. veitchii are commonly used indiscriminately in the herbal market. Moreover, Paeonia suffruticosa, an allied genus of P. lactiflora, is prescribed as Moutan Radicis Cortex. Therefore, accurate taxonomic identification of plant species is vital for quality assurance. A genetic assay is a reliable tool for accurately discriminating species in processed herbal medicines. To develop a genetic assay for the identification of four Paeonia species (P. lactiflora, P. anomala subsp. veitchii, P. japonica, and P. suffruticosa), we analyzed the sequences of two DNA barcoding regions, internal transcribed spacer and rbcL. A conventional PCR assay was established in this study for simple and rapid species identification using sequence characterized amplified region (SCAR) markers based on arbitrary nucleotide-containing primers. This assay was verified to be species specific and highly sensitive and could be applied to Paeonia species identification at an affordable rate.

Challenges in Medicinal and Aromatic Plants DNA Barcoding-Lessons from the Lamiaceae

The potential value of DNA barcoding for the identification of medicinal plants and authentication of traded plant materials has been widely recognized; however, a number of challenges remain before DNA methods are fully accepted as an essential quality control method by industry and regulatory authorities. The successes and limitations of conventional DNA barcoding are considered in relation to important members of the Lamiaceae. The mint family (Lamiaceae) contains over one thousand species recorded as having a medicinal use, with many more exploited in food and cosmetics for their aromatic properties. The family is characterized by a diversity of secondary products, most notably the essential oils (EOs) produced in external glandular structures on the aerial parts of the plant that typify well-known plants of the basil (Ocimum), lavender (Lavandula), mint (Mentha), thyme (Thymus), sage (Salvia) and related genera. This complex, species-rich family includes widely cultivated commercial hybrids and endangered wild-harvested traditional medicines, and examples of potential toxic adulterants within the family are explored in detail. The opportunities provided by next generation sequencing technologies to whole plastome barcoding and nuclear genome sequencing are also discussed with relevant examples.

PCR-based rapid diagnostic tools for the authentication of medicinal mistletoe species

BACKGROUND

Taxilli Herba (TH) and Visci Herba (VH), defined as the leaves and branches of the mistletoe species Taxillus chinensis and Viscum coloratum, respectively, are popular herbal medicines in East Asia. However, commercial TH and VH products are frequently adulterated with related inauthentic mistletoe species, posing efficacy and safety concerns. Accurate species identification of herbal medicinal products is a prerequisite for quality control, but traditional morphological identification methods are hampered by difficulties in discriminating among closely related species and in identifying the source materials in processed products.

PURPOSE

This study aimed to develop sequence-characterized amplified region (SCAR) markers and a multiplex-SCAR assay for rapid and accurate identification of authentic TH and VH.

METHODS

The matK region was sequenced in a total of 20 samples from five mistletoe species, namely T. chinensis and V. coloratum, and three species often found in adulterated herbal medicines, T. sutchuenensis, V. articulatum, and Macrosolen tricolor. Species-specific nucleotide polymorphisms were identified and short regions (21-22 bp) containing at least two species-specific nucleotides close to the 3' end were incorporated into SCAR primers that produced uniquely sized PCR amplicons for each species. The five SCAR primer sets were also combined into a multiplex-SCAR assay.

RESULTS

The SCAR primers successfully generated amplicons of the expected size for each target species even with low-DNA templates or with templates containing DNA from multiple samples. No amplification was observed in non-target species. The SCAR markers and the multiplex-SCAR assay successfully identified commercial TH and VH products that were counterfeit or adulterated in both dried and processed products.

CONCLUSION

This is the first report to illustrate discrimination of genuine medicinal mistletoe species with DNA-based marker assays, enabling rapid and accurate species identification. The SCAR assays developed in this study will facilitate the standardization of commercial mistletoe products.

Verification of Thai ethnobotanical medicine "Kamlang Suea Khrong" driven by multiplex PCR and powerful TLC techniques

Kamlang Suea Khrong (KSK) crude drug, a traditional Thai medicine used for oral tonic and analgesic purposes, is obtained from three origins: the inner stem bark of Betula alnoides (BA) or the stems of Strychnos axillaris (SA) or Ziziphus attopensis (ZA). According to the previous reports, SA contains strychnine-type alkaloids that probably cause poisoning; however, only organoleptic approaches are insufficient to differentiate SA from the other plant materials. To ensure the botanical origin of KSK crude drug, powerful and reliable tools are desperately needed. Therefore, molecular and chemical identification methods, DNA barcoding and thin-layer chromatography (TLC), were investigated. Reference databases, i.e., the ITS region and phytochemical profile of the authentic plant species, were conducted. In case of molecular analysis, multiplex polymerase chain reaction (PCR) based on species-specific primers was applied. Regarding species-specific primers designation, the suitability of three candidate barcode regions (ITS, ITS1, and ITS2) was evaluated by genetic distance using K2P model. ITS2 presented the highest interspecific variability was verified its discrimination power by tree topology. Accordingly, ITS2 was used to create primers that successfully specified plant species of authentic samples. For chemical analysis, TLC with toluene:ethyl acetate:ammonia (1:9:0.025) and hierarchical clustering were operated to identify the authentic crude drugs. The developed multiplex PCR and TLC methods were then applied to identify five commercial KSK crude drugs (CK1-CK5). Both methods correspondingly indicated that CK1-CK2 and CK3-CK5 were originated from BA and ZA, respectively. Molecular and chemical approaches are convenient and effective identification methods that can be performed for the routine quality-control of the KSK crude drugs for consumer reliance. According to chemical analysis, the results indicated BA, SA, and ZA have distinct chemical profiles, leading to differences in pharmacological activities. Consequently, further scientific investigations are required to ensure the quality and safety of Thai ethnobotanical medicine known as KSK.

Molecular and morphological discrimination of Chrysanthemum indicum using allele-specific PCR and T-shaped trichome

Chrysanthemum indicum L. is a traditional oriental medicinal herb prepared as a tea from flowers that have been used in China and South Korea since ancient times. It has a long history in the treatment of hypertension, inflammation, and respiratory diseases. Among Chrysanthemum species, C. indicum has more active chemical components as well as better therapeutic effects, and C. indicum is mostly used for medicinal purposes in South Korea. However, the usage of C. indicum has become problematic over the years due to the abundance of adulterated Chrysanthemum and confusion with morphologically related species such as C. morifolium, C. boreale, and Aster spathulifolius. Thus, here we developed a method for molecular authentication using chloroplast universal region rpoC2 and morphological authentication based on T-shaped trichomes of the adaxial leaf surface. By using a species-specific primer derived from the rpoC2 region, we established a multiplex allele-specific PCR for the discrimination of C. indicum. Amplicons of 675 bp for C. indicum and 1026 bp for other Chrysanthemum species were produced using both rpoC2-specific and common primers. These primers can be used to analyze dried samples of Chrysanthemum. Morphological discrimination was performed using T-shaped trichomes present only on the adaxial leaf surface of C. indicum species, and then molecular markers were utilized to authenticate C. indicum products from adulterant samples available in the market. Our results indicate that these molecular markers in combination with morphological differentiation can serve as an effective tool for identifying C. indicum.

Establishment of conventional PCR and real-time PCR assays for accurate, rapid and quantitative authentication of four mistletoe species

Adulterants in processed food and herbal medicines reduce their safety, quality control, or pharmacological efficacy. Four mistletoe species, including Viscum coloratum, inhabit Korea. Leaves and branches of V. coloratum, defined as edible or medicinal mistletoe species in Korean, are used to prepare Korean herbal medicines as well as leached tea. However, other mistletoe species including Taxillus sutchuenensis var. duclouxii, Korthalsella japonica, and Loranthus tanakae are frequently distributed as authentic V. coloratum in Korean markets because of similarities in the branches morphology and Korean names of these species with V. coloratum. Although herbal medicines and food products prepared from the other mistletoe species are inauthentic, they are sold at high prices because of the rarity of these species. Thus, it is important to distinguish between authentic and inauthentic adulterant mistletoe species. In this study, we developed species-specific primer, based on matK sequences, suitable for both conventional PCR and real time PCR (qPCR) assay. These assays allowed rapid discrimination among all four mistletoe species. Moreover, qPCR assay enabled the detection of trace amounts of adulterant mistletoe species in V. coloratum samples. Furthermore, we used these assays to monitor commercial mistletoe products distributed in Korean markets. Our data suggest that these methods would serve as a reliable genetic tool to prevent adulteration and standardize the quality of commercial V. coloratum products.

Accurate and Rapid Identification of Longan Arillus and Litchi Semen by a Multiplex PCR Assay

Dimocarpus longan, Litchi chinensis, and Nephelium lappaceum are commercially valuable subtropical and tropical fruits of the Sapindaceae family. Arillus and seeds of the three species have very similar morphologies; however, the arillus of D. longan is used as the herbal medicine Longan Arillus and seeds of L. chinensis are used as Litchi Semen in Korean and Chinese pharmacopoeias. The adulteration of herbal medicines with inauthentic species, including the use of Aril and seed fractions acquired from a single species for two herbal medicines (e.g., Longan Arillus and Litchi Semen), is often driven by economic motives. DNA markers are a tool for the detection of adulterants in commercial products. To establish rapid and reliable assays for the genetic identification of authentic Longan Arillus and Litchi Semen, we developed DNA markers with high specificity and sensitivity based on internal transcribed spacer (ITS) sequences. The newly developed DNA markers and multiplex PCR assay may contribute to efforts to protect against adulteration, quality control, and the standardization of herbal medicines.

Rapid and Simple Species Identification of Cicada Exuviae Using COI-Based SCAR Assay

Cicadidae periostracum (CP), the medicinal name of cicada exuviae, is well-known insect-derived traditional medicine with various pharmacological effects, e.g., anticonvulsive, anti-inflammatory, antitussive, and anticancer effects; it is also beneficial for the treatment of Parkinson’s disease. For appropriate CP application, accurate species identification is essential. The Korean pharmacopoeia and the pharmacopoeia of the People’s Republic of China define Cryptotympana atrata as the only authentic source of CP. Species identification of commercially distributed CP based on morphological features, however, is difficult because of the combined packaging of many cicada exuviae in markets, damage during distribution, and processing into powder form. DNA-based molecular markers are an excellent alternative to morphological detection. In this study, the mitochondrial cytochrome c oxidase subunit I sequences of C. atrata, Meimuna opalifera, Platypleura kaempferi, and Hyalessa maculaticollis were analyzed. On the basis of sequence alignments, we developed sequence-characterized amplified-region (SCAR) markers for efficient species identification. These markers successfully discriminated C. atrata from the three other cicada species, and detected the adulteration of market CP samples. This SCAR assay is a rapid, simple, cheap, reliable, and reproducible method for species identification, regardless of sample form and status, and contributes to CP quality control.

Identification and Monitoring of Amomi Fructus and its Adulterants Based on DNA Barcoding Analysis and Designed DNA Markers

Amomi Fructus is one of the traditional medicines derived from the ripe fruits of the Zingiberaceae family of plants, which include Amomum villosum, A. villosum var. xanthioides, and A. longiligulare. Owing to their highly similar morphological traits, several kinds of adulterants of Amomi Fructus have been reported. Therefore, accurate and reliable methods of identification are necessary in order to ensure drug safety and quality. We performed DNA barcoding using five regions (ITS, matK, rbcL, rpoB, and trnL-F intergenic spacer) of 23 Amomi Fructus samples and 22 adulterants. We designed specific DNA markers for Amomi Fructus based on the single nucleotide polymorphisms (SNPs) in the ITS. Amomi Fructus was well separated from the adulterants and was classified with the species of origin based on the detected SNPs from the DNA barcoding results. The AVF1/ISR DNA marker for A. villosum produced a 270 bases amplified product, while the ALF1/ISF DNA marker produced a 350 bases product specific for A. longiligulare. Using these DNA markers, the monitoring of commercially distributed Amomi Fructus was performed, and the monitoring results were confirmed by ITS analysis. This method identified samples that were from incorrect origins, and a new species of adulterant was also identified. These results confirmed the accuracy and efficiency of the designed DNA markers; this method may be used as an efficient tool for the identification and verification of Amomi Fructus.

Comparative Morphological, Ultrastructural, and Molecular Studies of Four Cicadinae Species Using Exuvial Legs

Previous studies have suggested that exuviae can be used for the identification of cicada species, but the precise characteristics that differ among species have not been determined. Thus, we performed the first comparative analyses of the leg morphology, ultrastructure, and mitochondrial DNA sequences of exuviae of four dominant cicada species in Korea, Hyalessa maculaticollis (Motschulsky, 1866), Meimuna opalifera (Walker, 1850), Platypleura kaempferi (Fabricius, 1794) and Cryptotympana atrata (Fabricius, 1775), the source of Cicadidae Periostracum, a well-known traditional medicine. A morphological analysis revealed that the profemur length, femoral tooth angle, and distance between the intermediate and last tooth of the femoral comb are useful characteristics for identification. We also evaluated the usefulness of the size, degree of reflex, and number of spines on the mid-legs and hind legs as diagnostic features. An ultrastructural study showed that Meimuna opalifera has a unique surface pattern on the legs. The sequences obtained using exuviae were identical to previously obtained sequences for adult tissues. Moreover, in a phylogenetic analysis using CO1 sequences, each species formed a monophyletic cluster with high bootstrap support. Accordingly, multiple methodological approaches using exuviae might provide highly reliable identification tools. The integrative data provide useful characteristics for the exuviae-based identification of closely related species and for further taxonomic and systematic studies of Cicadinae.

Development of conventional PCR and real-time PCR assays to discriminate the origins of Chinese pepper oil and herbal materials from Zanthoxylum

BACKGROUND

To ensure the safety, quality and therapeutic efficacy of processed foods and herbal medicines, it is important to identify and discriminate economically motivated adulterants. Zanthoxylum schinifolium is sold at a higher price than other Zanthoxylum species and is frequently adulterated with closely related Zanthoxylum species because of its high demand as a Korean food ingredient and medicinal material in markets. In addition, the pericarps of three Zanthoxylum species (Z. schinifolium, Z. bungeanum and Z. piperitum) are defined as herbal medicine Zanthoxyli Pericarpium in Korean pharmacopoeias, but not Z. piperitum in Chinese pharmacopoeias. Further confusion arises in the morphological similarity between Z. armatum (adulterant) and Z. bungeanum. Therefore, the aim of this study was to develop a sequence characterized amplified region (SCAR) marker for discrimination of four Zanthoxylum species.

RESULTS

With the goal of developing rapid and reliable tools for genetic discrimination of authentic Zanthoxyli Pericarpium, we designed species-specific SCAR markers, based on ITS2 sequences, that generate amplicons of less than 200 bp. Using these markers, we established both conventional and real-time PCR assay methods capable of differentiating samples at the species level. We validated the ability of SCAR markers to authenticate edible oil and herbal medicine, and confirmed that some herbal medicines contaminated with Z. armatum are being distributed as Zanthoxyli Pericarpium in Korean and Chinese markets.

CONCLUSIONS

The SCAR markers and PCR methods described represent powerful tools for protecting against adulteration and ensuring standardization of processed foods and herbal medicine. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Authentication of the Herbal Medicine Angelicae Dahuricae Radix Using an ITS Sequence-Based Multiplex SCAR Assay

The accurate identification of plant species is of great concern for the quality control of herbal medicines. The Korean Pharmacopoeia and the Pharmacopoeia of the People's Republic of China define Angelicae Dahuricae Radix (Baek-Ji in Korean and Bai-zhi in Chinese) as the dried roots of Angelica dahurica or A. dahurica var. formosana belonging to the family Apiaceae. Discrimination among Angelica species on the basis of morphological characteristics is difficult due to their extremely polymorphic traits and controversial taxonomic history. Furthermore, dried roots processed for medicinal applications are indistinguishable using conventional methods. DNA barcoding is a useful and reliable method for the identification of species. In this study, we sequenced the internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes in A. dahurica, A. dahurica var. formosana, and the related species A. anomala and A. japonica. Using these sequences, we designed species-specific primers, and developed and optimized a multiplex sequence-characterized amplified region (SCAR) assay that can simply and rapidly identify respective species, and verify the contamination of adulterant depending on the polymerase chain reaction (PCR) amplification without sequencing analysis in a single PCR reaction. This assay successfully identified commercial samples of Angelicae Dahuricae Radix collected from Korean and Chinese herbal markets, and distinguished them from adulterants. This multiplex SCAR assay shows a great potential in reducing the time and cost involved in the identification of genuine Angelicae Dahuricae Radix and adulterant contamination.

Establishment of a PCR Assay for the Detection and Discrimination of Authentic Cordyceps and Adulterant Species in Food and Herbal Medicines

Accurate detection and differentiation of adulterants in food ingredients and herbal medicines are crucial for the safety and basic quality control of these products. Ophiocordyceps sinensis is described as the only fungal source for the authentic medicinal ingredient used in the herbal medicine "Cordyceps", and two other fungal species, Cordyceps militaris and Isaria tenuipes, are the authentic fungal sources for food ingredients in Korea. However, substitution of these three species, and adulteration of herbal material and dietary supplements originating from Cordyceps pruinosa or Isaria cicadae, seriously affects the safety and reduces the therapeutic efficacy of these products. Distinguishing between these species based on their morphological features is very difficult, especially in commercially processed products. In this study, we employed DNA barcode-based species-specific sequence characterized amplified region (SCAR) markers to discriminate authentic herbal Cordyceps medicines and Cordyceps-derived dietary supplements from related but inauthentic species. The reliable authentication tool exploited the internal transcribed spacer (ITS) region of a nuclear ribosomal RNA gene (nrDNA). We used comparative nrDNA-ITS sequence analysis of the five fungal species to design two sets of SCAR markers. Furthermore, we used a set of species-specific SCAR markers to establish a real-time polymerase chain reaction (PCR) assay for the detection of species, contamination, and degree of adulteration. We confirmed the discriminability and reproducibility of the SCAR marker analysis and the real-time PCR assay using commercially processed food ingredients and herbal medicines. The developed SCAR markers may be used to efficiently differentiate authentic material from their related adulterants on a species level. The ITS-based SCAR markers and the real-time PCR assay constitute a useful genetic tool for preventing the adulteration of Cordyceps and Cordyceps-related dietary supplements.

Authentication of Herbal Medicines Dipsacus asper and Phlomoides umbrosa Using DNA Barcodes, Chloroplast Genome, and Sequence Characterized Amplified Region (SCAR) Marker

Dried roots of Dipsacus asper (Caprifoliaceae) are used as important traditional herbal medicines in Korea. However, the roots are often used as a mixture or contaminated with Dipsacus japonicus in Korean herbal markets. Furthermore, the dried roots of Phlomoides umbrosa (Lamiaceae) are used indiscriminately with those of D. asper, with the confusing Korean names of Sok-Dan and Han-Sok-Dan for D. asper and P. umbrosa, respectively. Although D. asper and P. umbrosa are important herbal medicines, the molecular marker and genomic information available for these species are limited. In this study, we analysed DNA barcodes to distinguish among D. asper, D. japonicus, and P. umbrosa and sequenced the chloroplast (CP) genomes of D. asper and D. japonicus. The CP genomes of D. asper and D. japonicus were 160,530 and 160,371 bp in length, respectively, and were highly divergent from those of the other Caprifoliaceae species. Phylogenetic analysis revealed a monophyletic group within Caprifoliaceae. We also developed a novel sequence characterised amplified region (SCAR) markers to distinguish among D. asper, D. japonicus, and P. umbrosa. Our results provide important taxonomic, phylogenetic, and evolutionary information on the Dipsacus species. The SCAR markers developed here will be useful for the authentication of herbal medicines.

Peptide Nucleic Acid Based Molecular Authentication for Identification of Four Medicinal Paeonia Species Using Melting Array Analysis of the Internal Transcribed Spacer 2 Region

Accurate taxonomic identification of plant materials in herbal medicines is important for product quality control. The genus Paeonia (Saxifragales) is the source of the herbal preparations Paeoniae Radix (Paeoniae Radix Alba and Paeoniae Radix Rubra) and Moutan Radicis Cotex. However, confusion has arisen regarding their contents due to linguistic and taxonomic ambiguities, similar morphologies and different definitions of Paeoniae Radix in the Korean and Chinese national pharmacopoeias, leading to the distribution of adulterated products. To develop a method for identifying the four Paeonia species used in these medicines, three fluorescently-labeled peptide nucleic acid (PNA) probes were designed against ITS2 sequences containing single nucleotide polymorphisms (SNPs) and used in a real-time PCR melting curve assay. Each of the four Paeonia species was accurately identified using this analysis. The accuracy and analytical stability of the PNA melting curve assay was confirmed using commercially available samples of the four Paeonia species. This assay is a reliable genetic tool to distinguish between different Paeonia-derived herbal medicines and identify the botanical origins of Paeoniae Radix and Moutan Radicis Cortex. This technique may also contribute to quality control and standardization of herbal medicines by providing a reliable authentication tool and preventing the distribution of inauthentic adulterants.

The complete chloroplast genome sequence of Aconitum coreanum and Aconitum carmichaelii and comparative analysis with other Aconitum species

Aconitum species (belonging to the Ranunculaceae) are well known herbaceous medicinal ingredients and have great economic value in Asian countries. However, there are still limited genomic resources available for Aconitum species. In this study, we sequenced the chloroplast (cp) genomes of two Aconitum species, A. coreanum and A. carmichaelii, using the MiSeq platform. The two Aconitum chloroplast genomes were 155,880 and 157,040 bp in length, respectively, and exhibited LSC and SSC regions separated by a pair of inverted repeat regions. Both cp genomes had 38% GC content and contained 131 unique functional genes including 86 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. The gene order, content, and orientation of the two Aconitum cp genomes exhibited the general structure of angiosperms, and were similar to those of other Aconitum species. Comparison of the cp genome structure and gene order with that of other Aconitum species revealed general contraction and expansion of the inverted repeat regions and single copy boundary regions. Divergent regions were also identified. In phylogenetic analysis, Aconitum species positon among the Ranunculaceae was determined with other family cp genomes in the Ranunculales. We obtained a barcoding target sequence in a divergent region, ndhC–trnV, and successfully developed a SCAR (sequence characterized amplified region) marker for discrimination of A. coreanum. Our results provide useful genetic information and a specific barcode for discrimination of Aconitum species.