Authenticity versus botanical specificity: the use of interchangeable species

For centuries, botany predominantly existed as a subspecialty of medicine and medicinal plants were chosen specifically for their medicinal properties, oftentimes with a lack of exactness to botanical specificity. Greater sophistication in analytical techniques, including genetics, has allowed for greater levels of exactness in differentiating species than was historically possible. However, the medicinal plant trade has not kept up with this increasing level of sophistication, often using multiple species as the medicinal article of trade. Some of these interchangeably used species are codified in pharmacopoeias internationally, others are not. Some species are readily identifiable as genuine articles of trade whereas botanical specificity may be elusive or questionable. Pharmacopoeias provide the suite of identity, purity, and quality tests, that when complied with, gives a high level of confidence for ensuring an authentic botanical drug of trade, but may lack botanical preciseness. The occurrence of hybrids raises additional challenges that may or may not result in clinically relevant changes in the botanical drug.

Presented are examples of closely related species, some of which can be readily identified as authentic articles of medicinal trade according to pharmacopoeial identity tests but may not be identified with 100% botanical specificity. Included are points of discussion regarding the challenging nature of proper nomenclature and use of interchangeable species in the trade of medicinal plants with implications for traditional health care practitioners, medicinal plant traders, regulators, and medicinal plant manufacturers.