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

Abstract

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 DNAbased 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.

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

“…In Brazil for example, ginseng products have been found to be adulterated with a completely unrelated species from another family, Pfaffia spp., albeit locally known as Brazilian ginseng ( Palhares et al, 2015 ). The inadvertent contamination through plant misidentification during harvesting or cross-contamination during processing but also the intentional and fraudulent use of filler species or cheaper substitutes, present on the herbal product market ( Jordan et al, 2010 ; Sgamma et al, 2017 ; Ichim et al, 2020 ), also affects the highly valued ginseng-containing food supplements and traditional medicines across the globalized market. The presence of substitutes or filler species in some cases reflects intentional, economically motivated and fraudulent practices by producers or vendors although the European Pharmacopoeia (Ph.…”

Potential Risks of Plant Constituents in Dietary Supplements: Qualitative and Quantitative Analysis of Peganum harmala Seeds

“…Microscopy is a traditional method reported in the pharmacopoeia for plant identification. In a recent review, Ichim et al [ 30 ] examined the authenticity of 508 microscopically authenticated herbal products, sold in different countries, concluding that microscopy is a rapid and cost-efficient method and can cope with mixtures and impurities. We used both light and electron microscopy to visualize the peculiarities of Pgh seeds, in order to provide information to use in customs laboratories (for example), where microscopes could be of one type or another.…”

Medicinal Plants and Herbal Products From Brazil: How Can We Improve Quality?

“…In another review, Ichim et al (2020) show results of studies on authenticity using microscopic analysis on 508 herbal medicines and food supplements traded in thirteen countries or territories. All or at least most (>70%) herbal products were reported to be authentic in Argentina, China, Germany, Thailand, and Egypt.…”