Stefan Gafner

Botanical Society of America

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Chantal Bergeron

Ottawa Hospital

Roy Upton

Daniel Grenier

Université Laval

Jacquelyn R. Villinski

Jean‐Luc Wolfender

University of Geneva

Michelle R. Embry

Health and Environmental Sciences Institute

Mark Blumenthal

Botanical Society of America

Kurt Hostettmann

John Wiley & Sons (United States)

Constance A. Mitchell

Health and Environmental Sciences Institute

Ikhlas A. Khan

University of Mississippi

Cooperative Institutions

University of Illinois Chicago

University of Ottawa

University of Mississippi

National Institutes of Health

United States Pharmacopeial Convention

Oregon State University

Université Laval

University of Illinois Urbana-Champaign

Rutgers, The State University of New Jersey

United States Food and Drug Administration

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The ABC-AHP-NCNPR botanical adulterants program's laboratory guidance on analytical methods to detect adulterants in botanical materials

Planta Medica (2015)

Stefan Gafner Mark Blumenthal Steven Foster JH Cardellina IA Khan

As the market for herbal medicines and dietary supplements increases, so do confirmed reports of undisclosed ingredients being added to botanical raw materials, extracts, essential oils, and finished botanical-based consumer products. These problems not only present a significant challenge to the global botanical medicine and herbal supplement industries but, more importantly, put the health and safety of the consumer at risk. Identifying suitable test methods is crucial for in-house quality control units and third-party analytical testing laboratories. However, the review and assessment of the available analytical methods is an expensive and time-consuming process. The ABC-AHP-NCNPR Botanical Adulterants Program Laboratory Guidance Documents (LGDs) identify the most suitable methods for the authentication of specific botanical materials and the detection of adulterants. The first in the series, a review of methods to authenticate and detect adulteration of skullcap (Scutellaria lateriflora), has been published in 2015. Next are the LGDs on bilberry (Vaccinium myrtillus) extract, and black cohosh (Actaea racemosa). The presentation will give an overview of the Program with a focus on the purpose and content of the LGDs.

Black cohosh

10.1055/s-0035-1556241

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Citations (1)

Evaluation of the Efficiency of Three Different Solvent Systems to Extract Triterpene Saponins from Roots of Panax quinquefolius Using High-Performance Liquid Chromatography

Journal of Agricultural and Food Chemistry (2004)

Stefan Gafner Chantal Bergeron Megan M. McCollom Lorena M. Cooper Kerry L. McPhail

Despite the wide availability of liquid herbal extracts using mixtures of alcohol, glycerin, and water, or glycerin and water as solvents, no data on the chemical composition of such extracts is readily available. In this study, the amount and the stability of the major saponins in Panax quinquefolius root extracts, made either with 50% (v/v) aqueous ethanol, a mixture (v/v/v) of 20% ethanol, 40% glycerin, and 40% water, or with 65% (v/v) aqueous glycerin, were evaluated by HPLC-UV analysis. The amount of total saponins was highest in the 50% aqueous ethanol extract (61.7 +/- 0.1 mg/g dry root), although similar to the ethanol-glycerin-water extract (59.4 +/- 0.5 mg/g dry root). Saponins were significantly lower in the 65% aqueous glycerin extract (51.5 +/- 0.2 mg/g dry root). Interestingly, the amounts of individual saponins were quite variable depending on the solvent. This is in part due to enzymatic cleavage of ginsenosides in the glycerin containing extracts during the maceration process. Storage of the extracts at 25 degrees C over the period of a year led to a 13-15% loss of saponins with all three types of extractions.

Maceration (sewage)

10.1021/jf0307503

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Citations (45)

The undisclosed presence of excipients and diluents in botanical extracts

HerbalGram (2024)

Stefan Gafner Loïc Loffredo James Kababick Stephen A. Wise Roy Upton

This article discusses the composition and labeling of botanical extracts, with particular focus on the sale of botanical dietary ingredients and dietary and food supplement products. Published literature and reports from analysts suggest that some commercial extracts in the dietary and food supplement supply chain may contain little or none of the declared plant or plant extract. Experts in dietary supplement analysis have determined that this occurs mainly because of two schemes used by deceptive suppliers. First, certain suppliers excessively dilute native plant extracts with undeclared amounts of excipients and are ambiguous in disclosing the plant-to-extract ratio. Second, whole herbs are extracted to obtain specific fractions or compounds that are considered to be therapeutically beneficial and are provided to select markets. The marc (leftover or spent biomass) may then be re-sold without disclosure that it is pre-extracted material.

Diluent

Dietary supplement

Food Products

Herbal supplement

10.59520/hg.bapp/psyd8392

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Cordyceps Botanical Adulterants Prevention Bulletin

Christopher Hobbs Roy Upton Stefan Gafner

Because of the great value of cordyceps (Ophiocordyceps sinensis, syn. Cordyceps sinensis), its rarity in the wild, and the difficulty of cultivating it, adulteration and substitution frequently occurs. The authenticity of any cordyceps raw material or finished product to be used in dietary or food supplements, or in products falling into another regulatory category, should be determined, if appropriate, by both DNA and chemical analysis. This is the case even when the mycelium is grown on nutritive substrates such as brown rice (Oryza sativa, Poaceae) and the species and strain of the fungal culture used as inoculum is confirmed, because other contaminating fungal species have been observed growing out preferentially over the intended species. Traditional Chinese medical practitioners and consumers familiar with the material known by the Chinese dong chong xiao cao (冬虫夏草) may continue to judge identity and quality morphologically but with the understanding that due to its expense, it is a highly adulterated material. This bulletin provides a summary on issues regarding the adulteration of products labeled to contain cordyceps for the herbal products industry, and those with interest in the quality of cordyceps in general. In addition to data on adulteration, the bulletin contains information about the taxonomy, importance in the market, analytical methods to detect adulteration, and consequences for the consumer and the industry.

10.59520/bapp.bapb/ydsi9045

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CHROMATOGRAPHIC FINGERPRINTING AS A MEANS OF QUALITY CONTROL: DISTINCTION BETWEEN ACTAEA RACEMOSA AND FOUR DIFFERENT ACTAEA SPECIES

Acta Horticulturae (2006)

Stefan Gafner Sidney Sudberg Élan M Sudberg Jacquelyn R. Villinski Robert Gauthier

10.17660/actahortic.2006.720.8

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Plant vs. kidney: Evaluating nephrotoxicity of botanicals with the latest toxicological tools

Current Opinion in Toxicology (2022)

Adam M. Pearson Stefan Gafner Cynthia V. Rider Michelle R. Embry Stephen Ferguson

Botanicals can cause nephrotoxicity via numerous mechanisms, including disrupting renal blood flow, damaging compartments along the nephron, and obstructing urinary flow. While uncommon, there are various reports of botanical-induced nephrotoxicity in the literature, such as from aristolochia (Aristolochia spp.) and rhubarb (Rheum spp.). However, at present, it is a challenge to assess the toxic potential of botanicals because their chemical composition is variable due to factors such as growing conditions and extraction techniques. Therefore, selecting a single representative sample for an in vivo study is difficult. Given the increasing use of botanicals as dietary supplements and herbal medicine, new approach methodologies (NAMs) are needed to evaluate the potential for renal toxicity to ensure public safety. Such approaches include in vitro models that use layers of physiological complexity to emulate the in vivo microenvironment, enhance the functional viability and differentiation of cell cultures, and improve sensitivity to nephrotoxic insults. Furthermore, computational tools such as physiologically based pharmacokinetic (PBPK) modeling can add confidence to these tools by simulating absorption, distribution, metabolism, and excretion. The development and implementation of NAMs for renal toxicity testing will allow specific mechanistic data to be generated, leading to a better understanding of the nephrotoxic potential of botanicals.

Nephrotoxicity

Aristolochia

10.1016/j.cotox.2022.100371

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Citations (4)

Grape Seed Extract Suppresses Lipopolysaccharide‐Induced Matrix Metalloproteinase (MMP) Secretion by Macrophages and Inhibits Human MMP‐1 and −9 Activities

Journal of Periodontology (2009)

Vu Dang La Chantal Bergeron Stefan Gafner Daniel Grenier

Background: Matrix metalloproteinases (MMPs) produced by resident and inflammatory cells in response to Gram‐negative periodontopathogens play a major role in the tissue destruction observed during periodontitis, a disease that affects tooth‐supporting structures. In this study, we investigated the effect of grape seed extract (GSE) on MMP secretion by human monocyte‐derived macrophages stimulated with Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans ) lipopolysaccharide (LPS) and on the activity of human recombinant MMP‐1 and −9. Methods: Macrophages were treated with various concentrations of GSE prior to being stimulated with A. actinomycetemcomitans LPS. The secretion of MMPs and activation of nuclear factor‐kappa B (NF‐κB) p65 and activator protein‐1 (AP‐1) were assessed by enzyme‐linked immunosorbent assay (ELISA). The effect of GSE on the catalytic activity of human recombinant MMP‐1 and −9 was tested using fluorogenic assays. Results: GSE inhibited the secretion of MMP‐1, −3, −7, −8, −9, and −13 by LPS‐stimulated macrophages in a concentration‐dependent manner. The suppression of MMP secretion was associated with inhibition of NF‐κB p65 and AP‐1 activation. Also, GSE dose‐dependently inhibited the activity of MMP‐1 and −9. Conclusion: The present study suggests that GSE may be potentially used in the development of novel host‐modulating strategies for the treatment of MMP‐mediated disorders such as periodontitis.

Aggregatibacter actinomycetemcomitans

Grape seed extract

Periodontal pathogen

10.1902/jop.2009.090251

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Citations (46)

Botanical drugs and supplements affecting the immune response in the time of COVID‐19: Implications for research and clinical practice

Phytotherapy Research (2020)

Thomas Brendler Ahmed Al‐Harrasi Rudolf Bauer Stefan Gafner Mary Hardy

In times of health crisis, including the current COVID-19 pandemic, the potential benefit of botanical drugs and supplements emerges as a focus of attention, although controversial efficacy claims are rightly a concern. Phytotherapy has an established role in everyday self-care and health care, but, since botanical preparations contain many chemical constituents rather than single compounds, challenges arise in demonstrating efficacy and safety. However, there is ample traditional, empirical, and clinical evidence that botanicals can offer some protection and alleviation of disease symptoms as well as promoting general well-being. Newly emerging viral infections, specifically COVID-19, represent a unique challenge in their novelty and absence of established antiviral treatment or immunization. We discuss here the roles and limitations of phytotherapy in helping to prevent and address viral infections, especially regarding their effects on immune response. Botanicals with a documented immunomodulatory, immunostimulatory, and antiinflammatory effects include adaptogens, Boswellia spp., Curcuma longa, Echinacea spp., Glycyrrhiza spp., medicinal fungi, Pelargonium sidoides, salicylate-yielding herbs, and Sambucus spp. We further provide a clinical perspective on applications and safety of these herbs in prevention, onset, progression, and convalescence from respiratory viral infections.

2019-20 coronavirus outbreak

10.1002/ptr.7008

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Citations (95)

Bilberry fruit extract laboratory guidance document

Stefan Gafner

Market demand for bilberry (Vaccinium myrtillus, Ericaceae) fruit extracts, combined with high prices and falling profit margins have resulted in unscrupulous manufacturers selling various ingredients labeled “bilberry extract.” Adulteration predominantly occurs with anthocyanin-rich extracts from other species, e.g., bog bilberry (V. uliginosum), lingonberry (V. vitis-idaea), European elder (Sambucus nigra, Adoxaceae), and Chinese mulberry (Morus australis, Moraceae). Additional adulterants reportedly include black soybean (Glycine max, Fabaceae) hull or black rice (Oryza sativa, Poaceae) extracts, and synthetic colorants like amaranth dye, an azo dye prohibited for use by the United States Food and Drug Administration (FDA) as a suspected carcinogen, and/or charcoal. This Laboratory Guidance Document presents a review of the various analytical technologies and methods used to differentiate between authentic bilberry extracts and potential adulterants.

Bilberry

Vaccinium myrtillus

10.59520/bapp.lgd/zlfx4530

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Inhibition of [³H]-LSD Binding to 5-HT₇ Receptors by Flavonoids from Scutellaria lateriflora

Journal of Natural Products (2003)

Stefan Gafner Chantal Bergeron Laura L. Batcha Jesse Reich J. T. Arnason

The hot water and 70% ethanol extracts of dried mad-dog skullcap (Scutellaria lateriflora) both bound to the 5-HT(7) receptor, with 87.2 +/- 6.2% and 56.7 +/- 1.3% inhibition of [(3)H]-LSD binding to the receptor at 100 microg/mL, respectively. The on-line analysis of a 70% ethanol extract by HPLC-UV/MS resulted in the identification of five flavones (1-5). Fractionation of the ethanol extract resulted in the isolation of three flavone-glucuronides (6-8) and a flavanone-glucuronide (9), including one new compound, lateriflorin (5,6,-dihydroxy-7-glucuronyloxy-2'-methoxyflavone) (8). The structure of 8 was determined by NMR ((1)H NMR, (13)C NMR, and NOESY experiments) and MS analysis. From the results obtained in the testing of the pure compounds, it is evident that the activity on the 5-HT(7) receptor is at least partly due to the presence of flavonoids. Scutellarin and ikonnikoside I showed the highest inhibition of [(3)H]-LSD binding with IC(50) values of 63.4 and 135.1 microM, respectively.

Flavones

Scutellarin

Flavanone

Baicalein

Scutellaria

Wogonin

Proton NMR

10.1021/np0205102

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Citations (42)