Identification of Ginkgo biloba supplements adulteration using high performance thin layer chromatography and ultra high performance liquid chromatography-diode array detector-quadrupole time of flight-mass spectrometry

Avula, Bharathi; Sagi, S; Gafner, Stefan; Upton, Roy; Wang, Yanhong; Wang, Mei; Khan, Ikhlas A.

doi:10.1007/s00216-015-8938-1

Cited by 53 publications

(35 citation statements)

References 19 publications

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“…This point is especially important as the presented results represent the first unambiguous proof that genistein is indeed a naturally occurring constituent of G. biloba leaves ( Figure 9) and by extension of the respective extract products -and therefore not prove of adulteration as claimed in previous publications [3,4]. Whereas these previous publications exclusively concentrated on commercially purchased G. biloba leave extracts, the preparation of which the authors had no influence on, all extract samples examined in the paper at hand were prepared in house at Zhejiang CONBA from leave samples collected personally by the authors.…”

supporting

confidence: 60%

Seasonal Variability of Genistein and 6-Hydroxykynurenic Acid Contents in Ginkgo biloba Leaves from Different Areas of China

Yao

Jin

et al. 2017

Natural Product Communications

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Refined extracts of Ginkgo biloba L. leaves can protect brain tissue from diverse types of tissue damage. Preliminary experiments identified 6-hydroxykynurenic acid (6-HKA) as a central contributor to this effect, and thus as a potential active marker for drug quality analysis. In contrast, genistein is a negative quality marker for this drug, as high contents of this compound in G. biloba leaves samples are in most cases caused by adulteration with Sophora flavescens Aiton, which is added to the extract by unlawful producers in order to boost its content in flavones, which serve as a quality marker. Some publications even dispute the natural occurrence of genistein in G. biloba leaves altogether, thus claiming that its presence even in trace amounts would prove adulteration. The present study aims to resolve the influence of harvesting time and location on the contents of genistein and 6-HKA-HPLC: Agilent SB-C18 column (5 µm, 4.6x250 mm); phosphoric acid pH2.5, acetonitrile, methanol, gradient; 1 mL/min; 25°C; UV 350 nm-in G. biloba leaves. The lowest contents of 6-HKA were observed in July and August, whereas the maximum was reached in May and October. In the case of genistein-its natural occurrence in G. biloba leaves could be demonstrated under controlled conditions for the first time-the lowest contents were found in May and June, whereas the highest were detected in September and October. These results show that harvesting of G. biloba leaves for pharmaceutical use should be avoided in July and August because of the reduced 6-HKA content, as well as in September and October, the season of highest genistein production. Due to both favorable 6-HKA production and a relative lack of genistein, May was identified as the ideal harvesting month for G. biloba leaves.

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supporting

confidence: 60%

Seasonal Variability of Genistein and 6-Hydroxykynurenic Acid Contents in Ginkgo biloba Leaves from Different Areas of China

Yao

Jin

et al. 2017

Natural Product Communications

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“…It has been reported that commercial ginkgo extracts may be adulterated with other flavonoid-rich extracts to increase their flavonoid content [18,19]. Chandra et al [19] recommended the combination of a qualitative determination of unhydrolyzed extracts as well as a quantitative analysis for total flavonol glycosides, including quercetin/kaempferol/isorhamnetin ratios, in hydrolyzed extracts to establish or track the authenticity of extracts.…”

Section: Samplementioning

confidence: 99%

“…Chandra et al [19] recommended the combination of a qualitative determination of unhydrolyzed extracts as well as a quantitative analysis for total flavonol glycosides, including quercetin/kaempferol/isorhamnetin ratios, in hydrolyzed extracts to establish or track the authenticity of extracts. Similarly, Avula et al [18] considered that measurement of the flavonoid composition without a prior hydrolysis step is a good analytical approach because it can provide assurance that the supplement has not been adulterated with either flavonol aglycones or flavonol glycosides.…”

Section: Samplementioning

confidence: 99%

Assessment of the Authenticity of Herbal Dietary Supplements: Comparison of Chemical and DNA Barcoding Methods

et al. 2017

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About 7 % of the U. S. population reports using botanical dietary supplements. Increased use of such supplements has led to discussions related to their authenticity and quality. Reports of adulteration with substandard materials or pharmaceuticals are of concern because such substitutions, whether inadvertent or deliberate, may reduce the efficacy of specific botanicals or lead to adverse events. Methods for verifying the identity of botanicals include macroscopic and microscopic examinations, chemical analysis, and DNA-based methods including DNA barcoding. Macroscopic and microscopic examinations may fail when a supplement consists of botanicals that have been processed beyond the ability to provide morphological characterizations. Chemical analysis of specific marker compounds encounters problems when these compounds are not distinct to a given species or when purified reference standards are not available. Recent investigations describing DNA barcoding analysis of botanical dietary supplements have raised concerns about the authenticity of the supplements themselves as well as the appropriateness of using DNA barcoding techniques with finished botanical products. We collected 112 market samples of frequently consumed botanical dietary supplements of ginkgo, soy, valerian, yohimbe, and St. John's wort and analyzed each for specific chemical markers (i.e., flavonol glycosides, total isoflavones, total valerenic acids, yohimbine, and hypericins, respectively). We used traditional DNA barcoding techniques targeting the nuclear ITS2 gene and the chloroplast gene A-H on the same samples to determine the presence of DNA of the labelled ingredient. We compared the results obtained by both methods to assess the contribution of each in determining the identity of the samples.

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“…The most common form of ginkgo adulteration is spiking with pure flavonoids (rutin and quercetin), hydrolyzed extracts or extracts from other flavonoid‐rich material such as Japanese sophora ( Styphnolobium japonicum )31 in order to comply with the compendial requirement for not less than 22% of flavonol glycosides. The limits for the content of rutin (not more than 4%) and quercetin (not more than 0.5%) was introduced in the compendia to detect these adulterated products 26.…”

Section: Usp Dietary Supplement Standardsmentioning

confidence: 99%

Dietary supplements quality analysis tools from the United States Pharmacopeia

Sarma

Giancaspro

Venema

2016

Drug Testing and Analysis

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The United States Food and Drug Administration (FDA) issued the dietary supplement (DS) current good manufacturing practice (GMP) regulations in compliance with the mandate from the Dietary Supplements Health and Education Act (DSHEA), with the intention of protecting public health by ensuring the quality of DS. The GMP regulations require manufacturers to establish their own quality specifications for identity, purity, strength, composition, and absence of contaminants. Numerous FDA‐conducted GMP inspections found that the private specifications set by these manufacturers are often insufficient to ensure adequate quality of dietary ingredients and DS. Wider use of the public standards developed by the United States Pharmacopeial Convention (USP), in conjunction with GMP compliance, can help ensure quality and consistency of DS as they do for medicines. Public health protection could be enhanced by strengthening the GMP provisions to require conformance with relevant United States Pharmacopeia–National Formulary (USP–NF) standards, or in the absence of USP standards, other public compendial standards. Another serious concern is the presence of synthetic drugs and drug analogues in products marketed as DS. Use of the new USP General Chapter Adulteration of Dietary Supplements with Drugs and Drug Analogs <2251> may reduce the exposure of consumers to dangerous drugs disguised as DS. © 2016 The Authors. Drug Testing and Analysis published by John Wiley & Sons Ltd.

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Identification of Ginkgo biloba supplements adulteration using high performance thin layer chromatography and ultra high performance liquid chromatography-diode array detector-quadrupole time of flight-mass spectrometry

Cited by 53 publications

References 19 publications

Seasonal Variability of Genistein and 6-Hydroxykynurenic Acid Contents in Ginkgo biloba Leaves from Different Areas of China

Seasonal Variability of Genistein and 6-Hydroxykynurenic Acid Contents in Ginkgo biloba Leaves from Different Areas of China

Assessment of the Authenticity of Herbal Dietary Supplements: Comparison of Chemical and DNA Barcoding Methods

Dietary supplements quality analysis tools from the United States Pharmacopeia

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