Integrated analytical assets aid botanical authenticity and adulteration management

Advancing botanical safety: A strategy for selecting, sourcing, and characterizing botanicals for developing toxicological tools

Increases in botanical use, encompassing herbal medicines and dietary supplements, have underlined a critical need for an advancement in safety assessment methodologies. However, botanicals present unique challenges for safety assessment due to their complex and variable composition arising from diverse growing conditions, processing methods, and plant varieties. Historically, botanicals have been largely evaluated based on their history of use information, based primarily on traditional use or dietary history. However, this presumption lacks comprehensive toxicological evaluation, demanding innovative and consistent assessment strategies. To address these challenges, the Botanical Safety Consortium (BSC) was formed as an international, cross-sector forum of experts to identify fit-for purpose assays that can be used to evaluate botanical safety. This global effort aims to assess botanical safety assessment methodologies, merging traditional knowledge with modern in vitro and in silico assays. The ultimate goal is to champion the development of toxicity tools for botanicals. This manuscript highlights: 1) BSC's strategy for botanical selection, sourcing, and preparation of extracts to be used in in vitro assays, and 2) the approach utilized to characterize botanical extracts, using green tea and Asian ginseng as examples, to build confidence for use in biological assays.

In Search of Authenticity Biomarkers in Food Supplements Containing Sea Buckthorn: A Metabolomics Approach

Sea buckthorn (Hippophae rhamnoides L.) (SB) is increasingly consumed worldwide as a food and food supplement. The remarkable richness in biologically active phytochemicals (polyphenols, carotenoids, sterols, vitamins) is responsible for its purported nutritional and health-promoting effects. Despite the considerable interest and high market demand for SB-based supplements, a limited number of studies report on the authentication of such commercially available products. Herein, untargeted metabolomics based on ultra-high-performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UHPLC-QTOF-ESI+MS) were able to compare the phytochemical fingerprint of leaves, berries, and various categories of SB-berry herbal supplements (teas, capsules, tablets, liquids). By untargeted metabolomics, a multivariate discrimination analysis and a univariate approach (t-test and ANOVA) showed some putative authentication biomarkers for berries, e.g., xylitol, violaxanthin, tryptophan, quinic acid, quercetin-3-rutinoside. Significant dominant molecules were found for leaves: luteolin-5-glucoside, arginine, isorhamnetin 3-rutinoside, serotonin, and tocopherol. The univariate analysis showed discriminations between the different classes of food supplements using similar algorithms. Finally, eight molecules were selected and considered significant putative authentication biomarkers. Further studies will be focused on quantitative evaluation.

Mass spectrometry-based approaches to assess the botanical authenticity of dietary supplements

Dietary supplements are legally considered foods despite frequently including medicinal plants as ingredients. Currently, the consumption of herbal dietary supplements, also known as plant food supplements (PFS), is increasing worldwide and some raw botanicals, highly demanded due to their popularity, extensive use, and/or well-established pharmacological effects, have been attaining high prices in the international markets. Therefore, botanical adulteration for profit increase can occur along the whole PFS industry chain, from raw botanicals to plant extracts, until final PFS. Besides the substitution of high-value species, unintentional mislabeling can happen in morphologically similar species. Both cases represent a health risk for consumers, prompting the development of numerous works to access botanical adulterations in PFS. Among different approaches proposed for this purpose, mass spectrometry (MS)-based techniques have often been reported as the most promising, particularly when hyphenated with chromatographic techniques. Thus, this review aims at describing an overview of the developments in this field, focusing on the applications of MS-based techniques to targeted and untargeted analysis to detect botanical adulterations in plant materials, extracts, and PFS.

Authentication of milk thistle commercial products using UHPLC-QTOF-ESI + MS metabolomics and DNA metabarcoding

BACKGROUND

Milk thistle is one of the most popular hepatoprotectants, and is often sold in combination with other ingredients. Botanical supplements are known to be vulnerable to contamination and adulteration, and emerging technologies show promise to improve their quality control.

METHODS

Untargeted and semi-targeted metabolomics based on UHPLC-QTOF-ESI⁺MS techniques, UV spectrometry, and DNA metabarcoding using Illumina MiSeq were used to authenticate eighteen milk thistle botanical formulations (teas, capsules, tablets, emulsion).

RESULTS

Untargeted metabolomics separated 217 molecules and by multivariate analysis the discrimination between the different preparations was established. The semi-targeted metabolomics focused on 63 phytochemicals, mainly silymarin flavonolignans and flavonoids, that may be considered as putative biomarkers of authenticity. All formulations contained molecules from silymarin complexes at different levels. The quantitative evaluation of silybins was done using in parallel UV spectrometry and UHPLC-QTOF-ESI⁺MS and their correlations were compared. DNA metabarcoding detected milk thistle in eleven out of sixteen retained preparations, whereas two others had incomplete evidence of milk thistle despite metabolomics validating specific metabolites, e.g., silymarin complex, identified and quantified in all samples. Meanwhile, the DNA metabarcoding provided insights into the total species composition allowing the interpretation of the results in a broad context.

CONCLUSION

Our study emphasizes that combining spectroscopic, chromatographic, and genetic techniques bring complementary information to guarantee the quality of the botanical formulations.

Horizon scan of DNA-based methods for quality control and monitoring of herbal preparations

Herbal medicines and preparations are widely used in healthcare systems globally, but concerns remain about their quality and safety. New herbal products are constantly being introduced to the market under varying regulatory frameworks, with no global consensus on their definition or characterization. These biologically active mixtures are sold through complex globalized value chains, which create concerns around contamination and profit-driven adulteration. Industry, academia, and regulatory bodies must collaborate to develop innovative strategies for the identification and authentication of botanicals and their preparations to ensure quality control. High-throughput sequencing (HTS) has significantly improved our understanding of the total species diversity within DNA mixtures. The standard concept of DNA barcoding has evolved over the last two decades to encompass genomic data more broadly. Recent research in DNA metabarcoding has focused on developing methods for quantifying herbal product ingredients, yielding meaningful results in a regulatory framework. Techniques, such as loop-mediated isothermal amplification (LAMP), DNA barcode-based Recombinase Polymerase Amplification (BAR-RPA), DNA barcoding coupled with High-Resolution Melting (Bar-HRM), and microfluidics-based methods, offer more affordable tests for the detection of target species. While target capture sequencing and genome skimming are considerably increasing the species identification resolution in challenging plant clades, ddPCR enables the quantification of DNA in samples and could be used to detect intended and unwanted ingredients in herbal medicines. Here, we explore the latest advances in emerging DNA-based technologies and the opportunities they provide as taxa detection tools for evaluating the safety and quality of dietary supplements and herbal medicines.

Detecting and Profiling of Milk Thistle Metabolites in Food Supplements: A Safety-Oriented Approach by Advanced Analytics

Milk thistle (Silybum marianum (L.) Gaertn.) is among the top-selling botanicals used as a supportive treatment for liver diseases. Silymarin, a mixture of unique flavonolignan metabolites, is the main bioactive component of milk thistle. The biological activities of silymarin have been well described in the literature, and its use is considered safe and well-tolerated in appropriate doses. However, commercial preparations do not always contain the recommended concentrations of silymarin, failing to provide the expected therapeutic effect. While the poor quality of raw material may explain the low concentrations of silymarin, its deliberate removal is suspected to be an adulteration. Toxic contaminants and foreign matters were also detected in milk thistle preparations, raising serious health concerns. Standard methods for determination of silymarin components include thin-layer chromatography (TLC), high-performance thin-layer chromatography (HPTLC), and high-performance liquid chromatography (HPLC) with various detectors, but nuclear magnetic resonance (NMR) and ultra-high-performance liquid chromatography (UHPLC) have also been applied. This review surveys the extraction techniques of main milk thistle metabolites and the quality, efficacy, and safety of the derived food supplements. Advanced analytical authentication approaches are discussed with a focus on DNA barcoding and metabarcoding to complement orthogonal chemical characterization and fingerprinting of herbal products.

Nomenclature: Herbal Taxonomy in the Global Commerce of Botanicals

In the world trade of medicinal plants, the naming of plants is fundamental to understanding which species are acceptable for therapeutic use. There are a variety of nomenclatural systems that are used, inclusive of common names, Latinized binomials, Galenic or pharmaceutical names, and pharmacopeial definitions. Latinized binomials are the primary system used for naming wild plants, but these alone do not adequately define medicinal plant parts. Each system has its specific applications, advantages, and disadvantages. The topic of medicinal plant nomenclature is discussed broadly by underscoring when and how varying nomenclatural systems should be used. It is emphasized that pharmacopeial definitions represent the only naming system that integrates plant identity, relevant plant parts, and the specific quality metrics to which a material must comply, thus affording the most appropriate identification method available for medicinal plant materials.

Quality Consistency of Herbal Products: Chemical Evaluation

The widespread utility of herbal products has been rising considerably worldwide, including both developed and developing countries, leading to the rapid growth of their availability in the United States and globally. This substantial increase in consumption of herbal products has witnessed the emergence of adverse effects upon oral administration of certain of these products, and thus has raised safety concerns. The adverse effects caused by the consumption of certain botanical medicines occur primarily as a result of the poor quality of plant raw materials or the finished products, which inherently may affect safety and/or efficacy. The poor quality of some herbal products can be attributed to a lack of proper quality assurance and quality control. A high demand for herbal products that surpasses production, combined with a desire for maximizing profits, along with a lack of rigorous quality control within some manufacturing facilities have led to the emergence of quality inconsistencies. The underlying causes for this involve the misidentification of plant species, or their substitution, adulteration, or contamination with harmful ingredients. Analytical assessments have revealed there to be frequent and significant compositional variations between marketed herbal products. The inconsistency of the quality of herbal products can be ascribed essentially to the inconsistency of the botanical raw material quality used to manufacture the products. Thus, the quality assurance and the quality control of the botanical raw materials is may contribute significantly to improving the quality and consistency of the quality of the end products. The current chapter focuses on the chemical evaluation of quality and consistency of herbal products, including botanical dietary supplements. Different techniques, instruments, applications, and methods used in identifying, quantifying, and generating chemical fingerprints and chemical profiles of the ingredients of the herbal products will be described. The strengths and weaknesses of the various techniques available will be addressed. Limitations of the other approaches including morphological or microscopic analysis and DNA-based analysis will be presented.

Quality evaluation of commercial herbal products using chemical methods

Herbal products comprise a wide spectrum of locally, nationally or internationally commercialized commodities. As these products have an increasingly important position in healthcare systems worldwide, a detailed product quality assessment is of crucial importance. For the quality evaluation of commercial herbal products, a wide range of methods were used, from simpler, quicker, and cost-effective HPTLC, to hyphenated methods with MS or NMR, where more precise quantification or specific structural information is required. Additionally, most of the methods have been coupled with chemometric tools, such as PCA, or PDA, for the multivariate analysis of the high amount of data generated by chromatograms, electropherograms or spectra. The chemical methods have revealed the widespread presence of low or variable quality herbal products in the marketplace. The majority of analytical investigations present major, qualitative and quantitative, inter-product variations of their chemical composition, ranging from missing ingredients, to strikingly and unnaturally high concentrations of some compounds. Moreover, the inter-batch quality variations were frequently reported, as well as the presence of some undesirable substances. The chemical analysis of herbal products is a vital component to raise the overall awareness of quality in the herbal market and generate a quality driven approach.

Interactions between Medical Plant-Derived Bioactive Compounds: Focus on Antimicrobial Combination Effects

It is accepted that the medicinal use of complex mixtures of plant-derived bioactive compounds is more effective than purified bioactive compounds due to beneficial combination interactions. However, synergy and antagonism are very difficult to study in a meticulous fashion since most established methods were designed to reduce the complexity of mixtures and identify single bioactive compounds. This study represents a critical review of the current scientific literature on the combined effects of plant-derived extracts/bioactive compounds. A particular emphasis is provided on the identification of antimicrobial synergistic or antagonistic combinations using recent metabolomics methods and elucidation of approaches identifying potential mechanisms that underlie their interactions. Proven examples of synergistic/antagonistic antimicrobial activity of bioactive compounds are also discussed. The focus is also put on the current challenges, difficulties, and problems that need to be overcome and future perspectives surrounding combination effects. The utilization of bioactive compounds from medicinal plant extracts as appropriate antimicrobials is important and needs to be facilitated by means of new metabolomics technologies to discover the most effective combinations among them. Understanding the nature of the interactions between medicinal plant-derived bioactive compounds will result in the development of new combination antimicrobial therapies.

Phytochemistry in the Ethnopharmacology of North and Central America

Traditionally the role of phytochemistry in the ethnopharmacology of North and Central America has been to characterize plant materials so that they can be produced reproducibly for commercial use or to identify active principles in unstudied traditional medicines for drug discovery. With new decolonial objectives coming from Indigenous communities, emphasis has shifted to evaluating the safety and efficacy of traditional medicines and preparations for community use. With new techniques and technologies available, scientific focus has shifted from individual bioactives to more rapid and comprehensive chemical characterizations and polypharmacy of traditional medicines. Untargeted metabolomics and associated statistical treatments have greatly expanded identification of components, improved species and cultivar identification and provided means for identifying multiple activity biomarkers, via chemometric and biochemometric analysis. New integrated techniques are available for identifying multiple active principles and synergists. The recent explosion of information is not without problems that need to be addressed including many unconfirmed tentative identifications of phytochemicals, lack of quantitative testing, superficial chemical activity testing and continuing need for dereplication.

Analytical Challenges and Metrological Approaches to Ensuring Dietary Supplement Quality: International Perspectives

The increased utilization of metrology resources and expanded application of its' approaches in the development of internationally agreed upon measurements can lay the basis for regulatory harmonization, support reproducible research, and advance scientific understanding, especially of dietary supplements and herbal medicines. Yet, metrology is often underappreciated and underutilized in dealing with the many challenges presented by these chemically complex preparations. This article discusses the utility of applying rigorous analytical techniques and adopting metrological principles more widely in studying dietary supplement products and ingredients, particularly medicinal plants and other botanicals. An assessment of current and emerging dietary supplement characterization methods is provided, including targeted and non-targeted techniques, as well as data analysis and evaluation approaches, with a focus on chemometrics, toxicity, dosage form performance, and data management. Quality assessment, statistical methods, and optimized methods for data management are also discussed. Case studies provide examples of applying metrological principles in thorough analytical characterization of supplement composition to clarify their health effects. A new frontier for metrology in dietary supplement science is described, including opportunities to improve methods for analysis and data management, development of relevant standards and good practices, and communication of these developments to researchers and analysts, as well as to regulatory and policy decision makers in the public and private sectors. The promotion of closer interactions between analytical, clinical, and pharmaceutical scientists who are involved in research and product development with metrologists who develop standards and methodological guidelines is critical to advance research on dietary supplement characterization and health effects.

Quantification of adulteration in traded ayurvedic raw drugs employing machine learning approaches with DNA barcode database

Adulteration of expensive raw drugs with inferior taxa has become a routine practice, conceding the quality and safety of derived herbal products. In this regard, the study addresses the development of an integrated approach encompassing DNA barcode and HPTLC fingerprinting to authenticate chiefly traded ayurvedic raw drugs in south India [viz. Saraca asoca (Roxb.) Willd., Terminalia arjuna (Roxb. ex DC.) Wight and Arn., Sida alnifolia L. and Desmodium gangeticum (L.) DC.] from its adulterants. Consortium of Barcode of Life (CBOL) recommended DNA barcode gene regions viz. nuclear ribosomal-Internal Transcribed Spacer (nrDNA-ITS), maturase K (matK), ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) and psbA-trnH spacer regions along with HPTLC profiling were experimented and a reference database was created. Further, an integrated analytical approach employing genetic distance-based Maximum Likelihood phylogenetic tree and Artificial Intelligence (AI)based Machine Learning Algorithms (MLA)-Waikato Environment for Knowledge Analysis (WEKA) and Barcoding with Logic (BLOG) were employed to prove efficacy of DNA barcode tool. Even though, among the four barcodes, psbA-trnH (S. alnifolia and its adulterants, T. arjuna and its adulterants) or ITS region (S. asoca and its adulterants, D. gangeticum and its adulterants) showed highest inter specific divergences in the selected Biological Reference Materials (BRMs), rbcL or matK barcode regions alone were successful for authentication of traded samples. The automated species identification techniques, WEKA and BLOG, experimented for the first time in India for raw drug validation, could achieve rapid and precise identification. A national certification agency for raw drug authentication employing an integrated approach involving a DNA barcoding tool along with standard organoleptic and analytical methods can strengthen and ensure safety and quality of herbal medicines in India.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-03001-5.

Quality Control of Herbal Medicines: From Traditional Techniques to State-of-the-art Approaches

Herbal medicines are important options for the treatment of several illnesses. Although their therapeutic applicability has been demonstrated throughout history, several concerns about their safety and efficacy are raised regularly. Quality control of articles of botanical origin, including plant materials, plant extracts, and herbal medicines, remains a challenge. Traditionally, qualitative (e.g., identification and chromatographic profile) and quantitative (e.g., content analyses) markers are applied for this purpose. The compound-oriented approach may stand alone in some cases (e.g., atropine in Atropa belladonna). However, for most plant materials, plant extracts, and herbal medicines, it is not possible to assure quality based only on the content or presence/absence of one (sometimes randomly selected) compound. In this sense, pattern-oriented approaches have been extensively studied, introducing the use of multivariate data analysis on chromatographic/spectroscopic fingerprints. The use of genetic methods for plant material/plant extract authentication has also been proposed. In this study, traditional approaches are reviewed, although the focus is on the applicability of fingerprints for quality control, highlighting the most used approaches, as well as demonstrating their usefulness. The literature review shows that a pattern-oriented approach may be successfully applied to the quality assessment of articles of botanical origin, while also providing directions for a compound-oriented approach and a rational marker selection. These observations indicate that it may be worth considering to include fingerprints and their data analysis in the regulatory framework for herbal medicines concerning quality control since this is the foundation of the holistic view that these complex products demand.

The integration of MS-based metabolomics and multivariate data analysis allows for improved quality assessment of Zingiber officinale Roscoe

Ginger (Zingiber officinale Roscoe) is consumed for health-promoting effects and as a food condiment. Comprehensive phytochemical analysis, other than gingerols and shogaols, has not yet been deeply investigated. Hence, the current research aimed to establish a non-targeted metabolomics approach for the discrimination between fresh ginger rhizome samples collected from four different producing countries, i.e., China, India, Pakistan, and Peru. In addition, lab-dried samples were analyzed to trace drying-induced metabolites. A comprehensive extraction procedure was carried out resulting in production of polar and non-polar fractions. The polar fraction was analyzed by ultra-performance liquid chromatography coupled with Fourier transform tandem mass spectrometry (UPLC-C18-FT-MS/MS) and gas chromatography coupled with time-of-flight mass spectrometry (GC-TOF-MS) post derivatization. UPLC-C8-FT-MS/MS was used for analysis of non-polar fraction. Results revealed for identification of a total of 253 metabolites. In addition, multivariate data analysis (MVDA), including principal component analysis (PCA) demonstrated clustering of Asian specimens. Several metabolites with a characteristic pattern for the origin revealing the highest contents of bioactive metabolites in the Peruvian product. Moreover, chemical markers identified, including [6]-gingerol and [6]-shogaol discriminating between fresh and dried samples. Furthermore, abundances of some primary metabolites, including amino acids and cinnamic acid, have confirmed the biosynthetic pathway of gingerols and their transformation upon drying to shogaols. The proposed approach can be applied as a potential candidate for quality assessment of ginger and other medicinal plants.

Tandem of Countercurrent Separation and qHNMR Enables Gravimetric Analyses: Absolute Quantitation of the Rhodiola rosea Metabolome

Off-line combination of countercurrent separation (CCS) and quantitative ¹H NMR (qHNMR) methodologies enabled the systematic dissection and gravimetric quantification of a chemically complex Rhodiola rosea crude extract (RCE). The loss-free nature and high selectivity of CCS achieved the quantitative discrimination of fatty acids (FAs), sugars, and proanthocyanidins (PACs) from ten other metabolite classes: phenylpropanoids, phenylethanoids, acyclic monoterpenoid glycosides, pinene derived glycosides, benzyl alcohol glycosides, cyanogenic glycosides, flavonoids, gallic acids, methylparabens, and cuminol glycosides. The ability of CCS to remove ("knockout") PACs completely resolved challenges with baselines that plague NMR and UHPLC analyses and produce inaccurate integral and AUC quantitation, respectively. NMR analysis of the non-PAC fractions enabled unambiguous identification of metabolites and their characteristic resonances for subsequent multitarget absolute quantification by qHNMR using a single, nonidentical internal calibrant (IC). An orthogonal LC-MS/MS method validated the gravimetric nature of the CCS-qHNMR analytical tandem. Underlying this LC-based cross-validation, comprehensive phytochemical isolation and characterization established 19 single-compound reference standards that represented all ten metabolite classes. Finally, quantum mechanical ¹H iterative Full Spin Analysis (HiFSA) of each standard provided a blueprint for future structural dereplication, identification, and quantification of Rhodiola marker constituents. The combination of two gravimetric analytical methods, loss-free CCS and IC-qHNMR, realizes the first chemical standardization of a botanical material that comprehensively captures a metabolome and permits absolute quantification.

Development of an analytical method for determination of polyphenols and total tannins from leaves of Syzygium cumini L. Skeels

Syzygium cumini L. Skeels belongs to Myrtaceae family. This species has been recognized by its antidiabetic, anti-inflammatory, and antimicrobial activities. Despite ever-increasing scientific interest for this species there is no pharmacopeia method for characterization and standardization of S. cumini yet. So, toward this aim, the objective of this work was to develop an efficient analytical methodology able to determine polyphenols and tannins content from leaves hydroethanolic extract of S. cumini using Folin-Ciocalteu method by ultraviolet absorption spectrophotometry (UV-Vis). The analytical methodology was developed for the first time in the literature for leaves of this specie shown to be fast and low-cost with results expressed through tannic acid equivalent (TAE). Moreover, the methodology presented selectivity with maximum absorption at 706 nm wavelength, linearity with R2>0.99; limit of detection 0.275 µg TAE mL-1 and 0.102 µg TAE mL-1; limit of quantification 1.046 µg TAE mL-1 and 0.912 µg TAE mL-1 for total polyphenols and total tannins, respectively. Furthermore, the methodology was accurate with recover value greater than 98%, as well as exact, reproductive, and robust with coefficient of variation values less than 15% for both compounds. All the results are found within the fixed limits according to RDC 166/2017.

Development of an HPTLC-based dynamic reference standard for the analysis of complex natural products using Jarrah honey as test sample

In this paper, we describe a novel approach to the development of a reference standard for the quality control of complex natural products, which will assist in the assessment of their authenticity and purity. The proposed method provides a template for the selection of samples, which can be pooled to obtain a reference standard. A shortfall of such an approach is, however, that the pooled sample is static in nature and therefore unable to capture difference in processing conditions or natural variations triggered by geographical or climatic impacts over time. To address this, the paper also outlines the development of a dynamic reference standard, which allows for ongoing adjustments to future variations. The method employs High-Performance Thin Layer Chromatography (HPTLC) derived extract profiles processed by multivariate analysis. The development of the dynamic reference standard is illustrated using honey, a complex natural matrix, as an example.

1H HR-MAS NMR-Based Metabolomic Fingerprinting to Distinguish Morphological Similarities and Metabolic Profiles of Maytenus ilicifolia, a Brazilian Medicinal Plant

Maytenus ilicifolia or "Espinheira-Santa" is a renowned Brazilian medicinal plant usually used against intestinal and stomach ulcers. Other species with similar thorny leaves have raised great confusion in order to discern the authentic M. ilicifolia. Misidentifications can lead to product adulteration of authentic M. ilicifolia with other species, which can be found on the Brazilian market. The intake of misclassified herbal products potentially could be fatal, demanding faster reliable fingerprinting-based classification methods. In this study, the use of ¹H HR-MAS NMR metabolomics fingerprinting and principal component analysis (PCA) allowed an evaluation of the authenticity for both collected and commercial M. ilicifolia samples, from the content of the flavanol, (-)-epicatechin (2), by observing variations in metabolic patterns. Plant specimen types from cultivated and natural habitats were analyzed by considering seasonal and topological differences. The interand intraplant topological metabolic profiles were found to be affected by seasonal and/or ecological trends such as sunlight, shade, rain, and the presence of pathogens. Moreover, several commercial samples, labeled as M. ilicifolia, were evaluated, but most of these products were of an inadequate quality.

Characteristic Malonyl Ginsenosides from the Leaves of Panax notoginseng as Potential Quality Markers for Adulteration Detection

Due to the high price and limited supply of Panax notoginseng, a large number of samples adulterated with the leaves appear in the market. A group of new malonyl ginsenosides were exclusively detected in the P. notoginseng leaves (PNL). Targeted isolation of the malonyl ginsenosides was guided by UPLC-QDa MS. HRMS, 1D/2D NMR, and chemical methods were used for structural identification. A selected ion monitoring method was developed based on UPLC-QDa MS to detect the adulterations. In addition, the anti-inflammatory activities and the collision-induced dissociation features of the isolated saponins were studied. As a result, eight new 3-OH malonylated dammarane-type triterpene oligoglycosides (notoginsenosides L3-L10) were obtained from PNL. Adulteration with PNL can be easily detected with limit of detection as low as 0.06%. To sum up, the isolated ginsenosides can be used as quality markers for fraud detection, which will promote the quality control of the notoginseng products.

Chemical Authentication of Botanical Ingredients: A Review of Commercial Herbal Products

Chemical methods are the most important and widely used traditional plant identification techniques recommended by national and international pharmacopoeias. We have reviewed the successful use of different chemical methods for the botanical authentication of 2,386 commercial herbal products, sold in 37 countries spread over six continents. The majority of the analyzed products were reported to be authentic (73%) but more than a quarter proved to be adulterated (27%). At a national level, the number of products and the adulteration proportions varied very widely. Yet, the adulteration reported for the four countries, from which more than 100 commercial products were purchased and their botanical ingredients chemically authenticated, was 37% (United Kingdom), 31% (Italy), 27% (United States), and 21% (China). Simple or hyphenated chemical analytical techniques have identified the total absence of labeled botanical ingredients, substitution with closely related or unrelated species, the use of biological filler material, and the hidden presence of regulated, forbidden or allergenic species. Additionally, affecting the safety and efficacy of the commercial herbal products, other low quality aspects were reported: considerable variability of the labeled metabolic profile and/or phytochemical content, significant product-to-product variation of botanical ingredients or even between batches by the same manufacturer, and misleading quality and quantity label claims. Choosing an appropriate chemical technique can be the only possibility for assessing the botanical authenticity of samples which have lost their diagnostic microscopic characteristics or were processed so that DNA cannot be adequately recovered.

The Untargeted Capability of NMR Helps Recognizing Nefarious Adulteration in Natural Products

Curcuma longa (turmeric) has an extensive history of ethnomedical use for common ailments, and "curcumin"-containing dietary supplements (CDS) are a highly visible portion of today's self-medication market. Owing to raw material cost pressure, CDS products are affected by economically motivated, nefarious adulteration with synthetic curcumin ("syncumin"), possibly leading to unexpected toxicological issues due to "residual" impurities. Using a combination of targeted and untargeted (phyto)chemical analysis, this study investigated the botanical integrity of two commercial "turmeric" CDS with vitamin and other additives that were associated with reported clinical cases of hepatotoxicity. Analyzing multisolvent extracts of the CDS by 100% quantitative ¹H NMR (qHNMR), alone and in combination with countercurrent separation (CCS), provided chemical fingerprints that allowed both the targeted identification and quantification of declared components and the untargeted recognition of adulteration. While confirming the presence of curcumin as a major constituent, the universal detection capability of NMR spectroscopy identification of significant residual impurities, including potentially toxic components. While the loss-free nature of CCS captured a wide polarity range of declared and unwanted chemical components, and also increased the dynamic range of the analysis, (q)HNMR determined their mass proportions and chemical constitutions. The results demonstrate that NMR spectroscopy can recognize undeclared constituents even if they represent only a fraction of the mass balance of a dietary supplement product. The chemical information associated with the missing 4.8% and 7.4% (m/m) in the two commercial samples, exhibiting an otherwise adequate curcumin content of 95.2% and 92.6%, respectively, pointed to a product integrity issue and adulteration with undeclared synthetic curcumin. Impurities from synthesis are most plausibly the cause of the observed adverse clinical effects. The study exemplifies how the simultaneously targeted and untargeted analytical principle of the 100% qHNMR method, performed with entry-level high-field instrumentation (400 MHz), can enhance the safety of dietary supplements by identifying adulterated, non-natural "natural" products.

A Review of Authenticity and Authentication of Commercial Ginseng Herbal Medicines and Food Supplements

Ginseng traditional medicines and food supplements are the globally top selling herbal products. Panax ginseng, Panax quinquefolius and Panax notoginseng are the main commercial ginseng species in herbal medicine. Prices of ginseng products vary widely based on the species, quality, and purity of the used ginseng, and this provides a strong driver for intentional adulteration. Our systematic literature search has reviewed the authenticity results of 507 ginseng-containing commercial herbal products sold in 12 countries scattered across six continents. The analysis of the botanical and chemical identity of all these products shows that 76% are authentic while 24% were reported as adulterated. The number of commercial products as well as the percentage of adulteration varies significantly between continents, being highest in South America (100%) and Australia (75%), and lower in Europe (35%), North America (23%), Asia (21%) and Africa (0%). At a national level, from the five countries for which more than 10 products have been successfully authenticated, the highest percentage of adulterated ginseng products were purchased from Taiwan (49%), followed by Italy (37%), China (21%), and USA (12%), while all products bought in South Korea were reported to be authentic. In most cases, labeled Panax species were substituted with other Panax species, but substitution of ginseng root, the medicinally recommended plant part, with leaves, stems or flowers was also reported. Efficient and practical authentication using biomarkers to distinguish the main ginseng varieties and secondary metabolite spectra for age determination are essential to combat adulteration in the global marketplace.

High-Resolution Magic Angle Spinning (HR-MAS) NMR-Based Fingerprints Determination in the Medicinal Plant Berberis laurina

Berberis laurina (Berberidaceae) is a well-known medicinal plant used in traditional medicine since ancient times; however, it is scarcely studied to a large-scale fingerprint. This work presents a broad-range fingerprints determination through high-resolution magical angle spinning (HR-MAS) nuclear magnetic resonance (NMR) spectroscopy, a well-established flexible analytical method and one of most powerful "omics" platforms. It had been intended to describe a large range of chemical compositions in all plant parts. Beyond that, HR-MAS NMR allowed the direct investigation of botanical material (leaves, stems, and roots) in their natural, unaltered states, preventing molecular changes. The study revealed 17 metabolites, including caffeic acid, and berberine, a remarkable alkaloid from the genus Berberis L. The metabolic pattern changes of the leaves in the course of time were found to be seasonally dependent, probably due to the variability of seasonal and environmental trends. This metabolites overview is of great importance in understanding plant (bio)chemistry and mediating plant survival and is influenceable by interacting environmental means. Moreover, the study will be helpful in medicinal purposes, health sciences, crop evaluations, and genetic and biotechnological research.

Microscopic Authentication of Commercial Herbal Products in the Globalized Market: Potential and Limitations

Herbal products are marketed and used around the globe for their claimed or expected health benefits, but their increasing demand has resulted in a proportionally increase of their accidental contamination or intentional adulteration, as already confirmed with DNA-based methods. Microscopy is a traditional pharmacopoeial method used for plant identification and we systematically searched for peer-reviewed publications to document its potential and limitations to authenticate herbal medicines and food supplements commercially available on the global market. The overall authenticity of 508 microscopically authenticated herbal products, sold in 13 countries, was 59%, while the rest of 41% were found to be adulterated. This problem was extending over all continents. At the national level, there were conspicuous differences, even between neighboring countries. These microscopically authenticated commercial herbal products confirm that different magnifying instruments can be used to authenticate crude or processed herbal products traded in the global marketplace. The reviewed publications report the successful use of different magnifying instruments, single or in combinations with a second one, with or without a chemical or DNA-based technique. Microscopy is therefore a rapid and cost-efficient method, and can cope with mixtures and impurities. However, it has limited applicability for highly processed samples. Microscopic authentication of commercial herbal products will therefore contribute to raise public awareness for the extent of adulteration and the need to safeguard consumer safety against the challenges of globalization.

Turning Meadow Weeds Into Valuable Species for the Romanian Ethnomedicine While Complying With the Environmentally Friendly Farming Requirements of the European Union's Common Agricultural Policy

The cross-compliance mechanism of the European Union (EU)'s common agricultural policy (CAP) makes the approval of the direct payments to the European farmers subject to compliance with the requirement to maintain the land in good agricultural and environmental condition. One of the obligations of the Romanian land owners and farmers is to avoid the installation of unwanted vegetation on their land plots. This vegetation is represented by some species of herbaceous or woody plants, annual or perennial, that spontaneously invade the agricultural lands, diminishing the production capacity of the cultivated plants. Included in this category are 10 meadow weeds, without fodder value or even toxic to animals: Arctium lappa L., Carduus nutans L., Conium maculatum L., Eryngium campestre L., Euphorbia cyparissias L., Pteridium aquilinum (L.) Kuhn, Rumex acetosella L., Veratrum album L., Xanthium spinosum L., and Xanthium strumarium L. Various and multiple uses in traditional medicine of these meadow weed species have been reported for Romania and other nine neighboring East European countries, i.e. Bosnia and Herzegovina, Bulgaria, Czech Republic, Estonia, Kosovo, Russia, Turkey, Serbia, and Ukraine. For A. lappa were recorded the highest number of ethnomedicinal uses, in the largest number of East European countries, including Romania. C. maculatum and V. album are not recommended for human consumption but can be further investigated as potential sources of pharmaceutically active compounds. Once removed by landowners and farmers from their land, the raw plant material of these 10 species become readily and easily available to the Romanian local communities and the industry of herbal food supplements, while the biodiversity of the agro-ecosystems is maintained.

NMR-Based Plant Metabolomics in Nutraceutical Research: An Overview

Few topics are able to channel the interest of researchers, the public, and industries, like nutraceuticals. The ever-increasing demand of new compounds or new sources of known active compounds, along with the need of a better knowledge about their effectiveness, mode of action, safety, etc., led to a significant effort towards the development of analytical approaches able to answer the many questions related to this topic. Therefore, the application of cutting edges approaches to this area has been observed. Among these approaches, metabolomics is a key player. Herewith, the applications of NMR-based metabolomics to nutraceutical research are discussed: after a brief overview of the analytical workflow, the use of NMR-based metabolomics to the search for new compounds or new sources of known nutraceuticals are reviewed. Then, possible applications for quality control and nutraceutical optimization are suggested. Finally, the use of NMR-based metabolomics to study the impact of nutraceuticals on human metabolism is discussed.

Improving natural product research translation: From source to clinical trial

While great interest in health effects of natural product (NP) including dietary supplements and foods persists, promising preclinical NP research is not consistently translating into actionable clinical trial (CT) outcomes. Generally considered the gold standard for assessing safety and efficacy, CTs, especially phase III CTs, are costly and require rigorous planning to optimize the value of the information obtained. More effective bridging from NP research to CT was the goal of a September, 2018 transdisciplinary workshop. Participants emphasized that replicability and likelihood of successful translation depend on rigor in experimental design, interpretation, and reporting across the continuum of NP research. Discussions spanned good practices for NP characterization and quality control; use and interpretation of models (computational through in vivo) with strong clinical predictive validity; controls for experimental artefacts, especially for in vitro interrogation of bioactivity and mechanisms of action; rigorous assessment and interpretation of prior research; transparency in all reporting; and prioritization of research questions. Natural product clinical trials prioritized based on rigorous, convergent supporting data and current public health needs are most likely to be informative and ultimately affect public health. Thoughtful, coordinated implementation of these practices should enhance the knowledge gained from future NP research.

The DNA-Based Authentication of Commercial Herbal Products Reveals Their Globally Widespread Adulteration

The herbal products, sold worldwide as medicines or foods, are perceived as low risk because they are considered natural and thus safe. The quality of these products is ineffectively regulated and controlled. The growing evidence for their lack of authenticity is causing deep concern, but the scale of this phenomenon at the global, continental or national scale remains unknown. We analyzed data reporting the authenticity, as detected with DNA-based methods, of 5,957 commercial herbal products sold in 37 countries, distributed in all six inhabited continents. Our global survey shows that a substantial proportion (27%) of the herbal products commercialized in the global marketplace is adulterated when their content was tested against their labeled, claimed ingredient species. The adulterated herbal products are distributed across all continents and regions. The proportion of adulterated products varies significantly among continents, being highest in Australia (79%), South America (67%), lower in Europe (47%), North America (33%), Africa (27%) and the lowest in Asia (23%). The commercial HPs' authenticity among the 37 countries included in our global analysis ranges between 0 and 100% from the total number of product reported for each specific national marketplace. For 9 countries, more than 100 products were successfully DNA-based authenticated and reported. From these countries, the highest percentage of adulterated commercial HPs was reported for Brazil (68%), followed distantly by Taiwan (32%), India (31%), USA (29%), followed closely by Malaysia (24%), Japan (23%), South Korea (23%), Thailand (20%), and China (19%). Our results confirm the large-scale presence of adulterated herbal products throughout the global market. The adulterated herbal products contain undeclared contaminant, substitute, and filler species, or none of the labeled species, which all may be accidental or intentional, economically-motivated and fraudulent. Due to the ever-increasing analytical sensitivity of the high throughput DNA sequencing, increasingly used for the untargeted, simultaneous multi-taxa identification, the proportion of adulterated HPs detected on the global market is expected to increase. In the context of the increasing demand for HPs, the limited supply of raw materials derived from many plant species, some of which being already nationally or internationally protected and having various degrees of trade restrictions, adds up to the differences and discrepancies between national HPs' regulatory frameworks and further increases the risks of adulteration of many types of herbal products. The globally widespread adulteration is a serious threat to consumers' well-being and safety, in spite of herbal products' claimed or expected health benefits.

Selection and characterization of botanical natural products for research studies: a NaPDI center recommended approach

Covering: up to the end of 2018 Dietary supplements, which include botanical (plant-based) natural products, constitute a multi-billion-dollar industry in the US. Regulation and quality control for this industry is an ongoing challenge. While there is general agreement that rigorous scientific studies are needed to evaluate the safety and efficacy of botanical natural products used by consumers, researchers conducting such studies face a unique set of challenges. Botanical natural products are inherently complex mixtures, with composition that differs depending on myriad factors including variability in genetics, cultivation conditions, and processing methods. Unfortunately, many studies of botanical natural products are carried out with poorly characterized study material, such that the results are irreproducible and difficult to interpret. This review provides recommended approaches for addressing the critical questions that researchers must address prior to in vitro or in vivo (including clinical) evaluation of botanical natural products. We describe selection and authentication of botanical material and identification of key biologically active compounds, and compare state-of-the-art methodologies such as untargeted metabolomics with more traditional targeted methods of characterization. The topics are chosen to be of maximal relevance to researchers, and are reviewed critically with commentary as to which approaches are most practical and useful and what common pitfalls should be avoided.

Detection of adulteration in Hydrastis canadensis (goldenseal) dietary supplements via untargeted mass spectrometry-based metabolomics

Current estimates report that approximately 25% of U.S. adults use dietary supplements for medicinal purposes. Yet, regulation and transparency within the dietary supplement industry remains a challenge, and economic incentives encourage adulteration or augmentation of botanical dietary supplement products. Undisclosed changes to the dietary supplement composition could impact safety and efficacy; thus, there is a continued need to monitor possible botanical adulteration or mis-identification. Goldenseal, Hydrastis canadensis L. (Ranunculaceae), is a well-known botanical used to combat bacterial infections and digestive problems and is widely available as a dietary supplement. The goal of this study was to evaluate potential adulteration in commercial botanical products using untargeted metabolomics, with H. canadensis supplements serving as a test case. An untargeted ultraperformance liquid chromatography-mass spectrometry (LC-MS) metabolomics analysis was performed on 35 H. canadensis commercial products. Visual inspection of the chemometric data via principal component analysis (PCA) revealed several products that were distinct from the main groupings of samples, and subsequent evaluation of contributing metabolites led to their confirmation of the outliers as originating from a non-goldenseal species or a mixture of plant materials. The obtained results demonstrate the potential for untargeted metabolomics to discriminate between multiple unknown products and predict possible adulteration.