Botanical Ingredient Forensics: Detection of Attempts to Deceive Commonly Used Analytical Methods for Authenticating Herbal Dietary and Food Ingredients and Supplements

Abstract

Botanical ingredients are used widely in phytomedicines, dietary/food supplements, functional foods, and cosmetics. Products containing botanical ingredients are popular among many consumers and, in the case of herbal medicines, health professionals worldwide. Government regulatory agencies have set standards (collectively referred to as current Good Manufacturing Practices, cGMPs) with which suppliers and manufacturers must comply. One of the basic requirements is the need to establish the proper identity of crude botanicals in whole, cut, or powdered form, as well as botanical extracts and essential oils. Despite the legal obligation to ensure their authenticity, published reports show that a portion of these botanical ingredients and products are adulterated. Most often, such adulteration is carried out for financial gain, where ingredients are intentionally substituted, diluted, or “fortified” with undisclosed lower-cost ingredients. While some of the adulteration is easily detected with simple laboratory assays, the adulterators frequently use sophisticated schemes to mimic the visual aspects and chemical composition of the labeled botanical ingredient in order to deceive the analytical methods that are used for authentication. This review surveys the commonly used approaches for botanical ingredient adulteration and discusses appropriate test methods for the detection of fraud based on publications by the ABC-AHP-NCNPR Botanical Adulterants Prevention Program, a large-scale international program to inform various stakeholders about ingredient and product adulteration. Botanical ingredients at risk of adulteration include, but are not limited to, the essential oils of lavender (Lavandula angustifolia, Lamiaceae), rose (Rosa damascena, Rosaceae), sandalwood (Santalum album, Santalaceae), and tea tree (Melaleuca alternifolia, Myrtaceae), plus the extracts of bilberry (Vaccinium myrtillus, Ericaceae) fruit, cranberry (Vaccinium macrocarpon, Ericaceae) fruit, elder (Sambucus nigra, Viburnaceae) berry, eleuthero (Eleutherococcus senticosus, Araliaceae) root, ginkgo (Ginkgo biloba, Ginkgoaceae) leaf, grape (Vitis vinifera, Vitaceae) seed, saw palmetto (Serenoa repens, Arecaceae) fruit, St. John’s wort (Hypericum perforatum, Hypericaceae) herb, and turmeric (Curcuma longa, Zingiberaceae) root/rhizome, among numerous others.

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

“…So far, no analytical method used as a stand-alone approach is able to comprehensively address the herbal product authenticity [ 38 , 94 , 109 ]. Thereby, a combination of complementary and orthogonal analytical techniques is generally recommended to ensure the quality and safety of herbal products [ 32 , 46 , 143 , 144 , 145 ]. Even though definitions for the terms “orthogonal” and “complementary” have been previously proposed in the field of quality control of pharmaceutical and biopharmaceutical products [ 146 ], they do not yet have a robust equivalent compatible with the existing analytical methods available for the quality control of herbal products.…”

“…Apart from the natural and induced complexity of these herbal matrices that are already raising challenges to assess their quality, it has been recently reported that suppliers and manufacturers are aware of the commonly used identification methods and have perfected ways to deceive such tests and to commit various types of fraud [ 22 ]. Silymarin is cited as a well-known example of this type of practices [ 30 , 32 ]. In this case, the manufacturers have been shown to make use of spectrophotometric methods for the standardization or obtaining the concentrations declared on the certificates of analysis and labels of the marketed products, even if these methods have been shown to produce a higher value for silymarin (i.e., 30–65% by HPLC-UV vs. 65–80% by spectrophotometric methods) [ 30 , 32 ].…”

“…In this case, the manufacturers have been shown to make use of spectrophotometric methods for the standardization or obtaining the concentrations declared on the certificates of analysis and labels of the marketed products, even if these methods have been shown to produce a higher value for silymarin (i.e., 30–65% by HPLC-UV vs. 65–80% by spectrophotometric methods) [ 30 , 32 ]. To avoid this heterogeneity of declared information, the method that has been used for the quantification of the targeted compound should always be declared by the manufactures [ 32 ]. McCutcheon [ 30 ] extracted evidence from the literature showing that 30 to 50% of commercial MT extracts do not comply with their label claims.…”

“…Some of the studies also reported the presence of foreign matters in the investigated commercial preparations, suspected as being adulterants, but their identity was not determined [ 19 , 29 , 30 , 31 ]. Though novel testing and quality monitoring strategies have been recently developed and applied to characterize the composition of MT products and to check for possible adulteration, fraudulent manufacturers and suppliers found ways to deceive such tests [ 32 ].…”

Elderberry Extracts: Characterization of the Polyphenolic Chemical Composition, Quality Consistency, Safety, Adulteration, and Attenuation of Oxidative Stress- and Inflammation-Induced Health Disorders

“…Recently, it has been observed that adulterators are using sophisticated approaches to deceive the analytical methods in order to evade the detection of adulterants. Consequently, assessing the authenticity of S. nigra which is frequently adulterated with black rice extract by analyzing its anthocyanin profile using methods such as UV/vis, HPTLC, and HPLC-UV/vis will put these adulteration methods at risk of detection [ 45 ].…”