Dear Reader

The Botanical Adulterants Prevention Program (BAPP) has released four more peer-reviewed publications between September and November 2018. The Maca Botanical Adulterants Prevention Bulletin and the Tea Tree Oil Laboratory Guidance Document (LGD) were published in September, followed by a revised bulletin on saw palmetto berries and berry extracts in October, and the LGD on cranberry, which was issued in November.

Maca, a root crop originating in the Andean mountains has been used as a food and medicine for thousands of years by the local people. The interest in this plant has increased dramatically over the past two decades, fueled by reports on maca’s benefits to enhance sexual stamina. Along with the increased demand came reports of adulteration, primarily by adding undeclared starches from various sources, e.g., corn or yam, but also instances of conventional erectile dysfunction drugs added to finished products labeled to contain maca. The maca bulletin provides a summary on these issues. The newly released laboratory guidance document on tea tree oil complements the tea tree oil adulteration bulletin published in August 2017. It details commonly used authentication methods for tea tree oil, and evaluates these methods for their ability to authenticate tea tree oil, and to detect adulteration. The update of the saw palmetto bulletin was prompted by reports of designer blends consisting mainly of fatty acids of animal origin labeled as saw palmetto extracts. The adulterated materials are difficult to detect since they often meet specifications set by pharmacopeial monographs. The latest BAPP publication, the LGD on cranberry products, provides information on analytical methods to detect adulteration of cranberry juice and fruit extracts. A primary focus of the LGD is the analytical methods that are capable of distinguishing the cranberry proanthocyanidins and anthocyanins from those of other plant sources. Details on the updated saw palmetto bulletin, the maca bulletin, and the tea tree oil and cranberry laboratory guidance documents are provided in the Program News section of this newsletter.

The Science section contains summaries and comments on five publications. Bakhytkyzy et al. analyzed 17 commercial products labeled to contain cranberry by high-performance liquid chromatography with fluorescence detection. Several of these products contained additional ingredients such as grape seed or hibiscus extracts. Quantitative data for catechin, epicatechin, and procyanidins A2 and B2 were then used to cluster the products. Two of the products lacked procyanidin A2, which is known to occur in authentic cranberry. A new Fourier-transform infrared (FT-IR) method, published by Liu et al., allows the detection of four common goldenseal adulterants at levels generally between 5-20% in cases where materials are purchased in whole, cut, or powdered root form. The paper by Molina et al. details the results of a science education initiative within high schools in New York City. The project was designed to determine the identity of ingredients by DNA barcoding in 32 single-ingredient herbal dietary supplements containing crude powdered plant material. Amplification success was low with 62.5% of samples providing a DNA sequence. Out of the 20 samples for which a barcode was obtained, 16 (80%) corresponded to the labeled species. In another paper presenting a genetic approach, Liu et al. used species specific primers to detect adulteration of ginkgo leaf with Japanese sophora. The researchers analyzed commercial ginkgo products in form of teas (n = 8) or dietary supplements (n = 28) that were purchased online. None of the tea samples was adulterated, but nine dietary supplements (32%) contained a mixture of ginkgo and Japanese sophora. Finally, Sica et al. presented the results of an investigation into the usefulness of UHPLC-CAD fingerprints to distinguish four commercial grape seed extracts (GSEs) from peanut skin and Maritime pine bark extracts, and to characterize the chemical composition of GSEs in general. For the reference GSE, polar compounds (salts, amino acids, organic acids, and sugars) made up 16% of the extract, while nonpolar compounds (fatty acids and sterols) accounted for 1%. The remainder of the extract (83%) consisted of polyphenolic compounds.

We hope that the information included in this issue of the Botanical Adulterants Monitor will be useful. Feel free to circulate the information among your colleagues with the goal that the information will help to avoid adulterated ingredients’ finding their way into the supply chain for herbal dietary supplements and other finished botanical products.

Stefan Gafner, PhD
Chief Science Officer
American Botanical Council
Technical Director, ABC-AHP-NCNPR Botanical Adulterants Program