DNA Barcoding for Industrial Quality Assurance

Abstract

DNA barcoding methods originally developed for the identification of plant specimens have been applied to the authentication of herbal drug materials for industrial quality assurance. These methods are intended to be complementary to current morphological and chemical methods of identification. The adoption of these methods by industry will be accelerated by the introduction of DNA-based identification techniques into regulatory standards and monographs. The introduction of DNA methods into the British Pharmacopoeia is described, along with a reference standard for use as a positive control for DNA extraction and polymerase chain reaction (PCR). A general troubleshooting chart is provided to guide the user through the problems that may be encountered during this process. Nevertheless, the nature of the plant materials and the demands of industrial quality control procedures mean that conventional DNA barcoding is not the method of choice for industrial quality control. The design of DNA barcode-targeted quantitative PCR and high resolution melt curve tests is one strategy for developing rapid, robust, and reliable protocols for high-throughput screening of raw materials. The development of authentication tests for wild-harvested L. is used as a case study to exemplify these relatively simple tests. By way of contrast, the application of next-generation sequencing to create a complete profile of all the biological entities in a mixed herbal drug is described and its potential for industrial quality assurance discussed.

Benefits and Limitations of DNA Barcoding and Metabarcoding in Herbal Product Authentication

“…In recent years in the field of medicinal plants research on DNA barcoding remarkable progress has been made, as reviewed by Techen et al (2014) and de Boer et al (2015). Initially used as an identification tool, DNA barcoding is now applied in the industrial quality assurance context to authenticate a wide range of herbal products Parveen et al, 2016;Sgamma et al, 2017). Recently, the British Pharmacopoeia included the first globally general DNA-based identification method using Ocimum tenuiflorum L. (Lamiaceae), with the focus on plant sampling, barcode regions, DNA extraction, purification and amplification, and the sequences reference database Sgamma et al, 2017).…”

“…Initially used as an identification tool, DNA barcoding is now applied in the industrial quality assurance context to authenticate a wide range of herbal products Parveen et al, 2016;Sgamma et al, 2017). Recently, the British Pharmacopoeia included the first globally general DNA-based identification method using Ocimum tenuiflorum L. (Lamiaceae), with the focus on plant sampling, barcode regions, DNA extraction, purification and amplification, and the sequences reference database Sgamma et al, 2017). Recent investigations applied DNA barcoding to identify and authenticate various marketed herbal products, reporting various degrees of discrepancy between the expected species and the actual identified species.…”

“…In the wake of these studies and of other recent cases exposing discrepancies between labelling and constituents actually present in the products, serious concerns were raised about the authenticity and quality of herbal products. Sgamma et al (2017) discusses the feasibility and the main aspects of using DNA barcoding in industrial quality assurance procedures. However, conventional DNA barcoding faces practical limitations restricting the method to the authentication of a single ingredient herbal preparations exclusively, and only for unprocessed plant material thus before the plant undergoes various extractions and processing steps that usually lead to loss, degradation or mixing of DNA.…”

Botanical origin authentication of dietary supplements by DNA‐based approaches

“…Being considered as foods, dietary supplements do not require any approval from regulatory agencies before being introduced in the market, with manufacturers and suppliers being responsible for their safety and conformity with food law requirements (Raclariu, Heinrich, Ichim, & Boer, 2018; Rocha, Amaral, & Oliveira, 2016). Therefore, in several countries, guidelines have been established with regard to the safety of botanicals and botanical products, including the Current Good Manufacturing Practices for food supplements (FDA Regulation, 2007) and Good Agricultural and Collection Practices (Moraes, Still, Lum, & Hirsch, 2015; Raclariu et al., 2018; Sgamma et al., 2017; Smillie & Khan, 2010; van den Berg, Serra‐Majem, Coppens, & Rietjens, 2011). Even so, with the growing demand for dietary supplements in both developed and developing countries and the consequent increase of the global market of these products, which is expected to reach US$ 140 billion by 2024 (Global Industry Analyst, Inc., 2018; Newmaster, Grguric, Shanmughanandhan, Ramalingam, & Ragupathy, 2013; Sucher & Carles, 2008), different safety issues have emerged recently.…”

“…), the complexity of formulation, and the prior knowledge of possible adulterants. The identification of medicinal plants in dried and/or fragmented bulk plant material can be performed based on the morphological identification by means of macroscopic and/or microscopic analysis (Sgamma et al., 2017). However, macroscopic analysis requires the plant or plant part to be intact, being inadequate for powders and extracts.…”