AHP Publishes Monograph with Analytical Standards for Boneset (Eupatorium perfoliatum)

The American Society of Pharmacognosy (ASP) and the Society for Medicinal Plant and Natural Product Research (GA) have announced their

Reviewed: Upton R, Petrone C. American Herbal Pharmacopoeia and Therapeutic Compendium: Boneset Aerial Parts: Eupatorium perfoliatum L. Scotts Valley, CA: American Herbal Pharmacopoeia. Monograph; 2019.

Keywords: Adulteration, AHP monograph, Eupatorium cannabinum, Eupatorium perfoliatum, Eutrochium purpureum, HPLC, HPTLC, macroscopic identification, microscopic identification

The monograph on boneset (Eupatorium perfoliatum, Asteraceae) aerial parts, marking the 40th publication in the series of AHP monographs, provides the most detailed collection of information to date on the medical history, therapeutic benefits, and methods of analysis of the plant. A native American plant, boneset is frequently used by naturopaths and herbalists for flu, cough, pain, and for its laxative and diaphoretic effects. As in all AHP monographs, this document contains information on the history of use, commercial sources, taxonomy, chemistry and analysis, therapeutic and safety data, as well as regulations regarding its sale in the United States and abroad. For the purpose of this newsletter, only the section on authentication and chemical analysis has been reviewed.

The monograph has a short section on potential substitutes and adulterants, which mainly include other Eupatorium spp. and Eutrochium purpureum (syn. Eupatorium purpureum, Asteraceae). Ageratina altissima (syn. Eupatorium rugosum, Asteraceae) is listed as a historical adulterant. Botanical identification criteria are provided for E. perfoliatum, E. cannabinum, Eutrochium purpureum, and A. altissima. Distinction of the plants, particularly during the flowering period, is possible using the taxonomic characteristics.

As in every AHP monograph, macroscopic and microscopic identification criteria for E. perfoliatum are provided as text and illustrations. Boneset can be distinguished from E. cannabinum using macroscopic features; however, no macroscopic or microscopic information on the other confounding species is provided. The analytical section provides high-performance thin-layer chromatography (HPTLC) images of the aerial parts of boneset and four additional species, E. cannabinum, E. fortunei, E. purpureum, and Eutrochium purpureum. Also shown are HPTLC traces of E. maculatum and Eutrochium purpureum roots. The fingerprints of E. perfoliatum, E. cannabinum, E. purpureum, and Eutrochium purpureum are surprisingly similar and do not allow a clear distinction of these species. Also described is a 60-minute high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method for caffeic acid derivatives and flavonoids. To date, no comparison of the HPLC-UV fingerprint with other Eupatorium species or Eutrochium purpureum has been performed. For analysis of the hepatotoxic pyrrolizidine alkaloids (PAs), the reader is referred to the 2018 paper by Colegate et al.¹

Comment: In publishing this monograph, AHP has provided a unique resource for the identification and quality control of this important medicinal plant. While the recently discovered occurrence of PAs in the aerial parts may limit the use of the plant, new breeding or processing technologies may lead to PA-free boneset ingredients in the future. The monograph certainly provides the necessary tools to determine boneset quality and distinguish among boneset and potential confounding materials by taxonomic means. Whether methods based on comparison of the chemical compositions can be used to differentiate closely-related species needs to be determined in future studies. The monograph is the most comprehensive scientific review ever compiled on Eupatorium perfoliatum. It is of greater significance today, because during the influenza pandemic of 1918, E. perfoliatum preparations were reportedly one of the most widely used Eclectic drugs for the prevention and treatment of influenza patients. Therefore, attention to the plant is heightened today, especially on the internet, based on the historical record in previous influenza epidemics. Adulteration, misidentification, and substitution of boneset could be more prevalent during the current COVID-19 pandemic.

Reference

1. Colegate SM, Upton R, Gardner DR, Panter KE, Betz JM. Phytochem Anal. 2018;29(6):613-626.