The elevated demand for medical herbal preparations has promoted a fast growth of their manufacture and trade. Nevertheless, currently, there are no standardized methods to identify the plant ingredients contained in these products. As a consequence, the authenticity and quality of herbal preparations is often at risk.

By using the genetic method DNA barcoding, Steven Newmaster, University of Guelph, ON, Canada, and colleagues tested the authenticity of 44 herbal products from 12 different companies. The analysis revealed that 59 % of the products examined contained species of plants not listed on the labels. In some cases, the main herbal ingredients indicated on the labels were absent and substituted with other ingredients. In other cases, the herbal preparations were contaminated with substances known to be toxic and to provoke side effects. Furthermore, in some products, rice, soybean, and grasses were used as fillers, thus representing a potential heath risk for people allergic to these plants.

The authentication of herbal products with DNA barcoding methods is thus necessary to provide costumers with safe and high quality preparations.

• DNA barcoding detects contamination and substitution in North American herbal products,
  Steven G Newmaster, Meghan Grguric, Dhivya Shanmughanandhan, Sathishkumar Ramalingam, Subramanyam Ragupathy,
  BMC Med. 2013, 11, 222.
  DOI: 10.1186/1741-7015-11-222