Comparison of Analytical Methods Used for Standardization of Triterpenoid Saponins in Herbal Monographs Included in the Russian and Other Pharmacopeias

ABSTRACT Introduction Harmonization of methodological approaches to the analysis of herbal substances containing triterpenoid saponins, considered the largest group of phytochemicals, is essential for the pharmaceutical industry worldwide. Objectives This review aimed to perform a comparative analysis of the requirements for the standardization of herbal substances, herbal medicinal products (HMPs), and other herbal materials containing triterpenoid saponins in the pharmacopeial texts of the Russian Federation and the world's leading pharmacopeias. Materials and Methods The review covers the data on the quantitative and qualitative analysis of herbal substances containing triterpenoid saponins, as presented in the State Register of Medicinal Products of Russia and the monographs of the world's leading pharmacopeias: the European Pharmacopeia, United States Pharmacopeia, British Pharmacopeia, Japanese Pharmacopeia, and the national pharmacopeias of the Eurasian Economic Union (EEU) Member States. Results This review compares and discusses the analytical methods used for the standardization of Aesculus hippocastanum L. seeds, Aralia elata (Miq.) Seem roots, Glycyrrhiza spp. roots, Orthosiphon aristatu s (Blume) Miq. leaves, and Polemonium caeruleum L. rhizomes with roots. The most common analytical methods used are (HP)TLC and (U)HPLC. The Russian Pharmacopeia also includes titrimetry and spectrophotometry. Conclusions The appropriate selection of a group of biologically active compounds for HMP standardization is still challenging. We believe that a rational approach to the standardization of herbal substances and HMPs should be based on the use of herbal substances with maximum extractability and specific pharmacological activity. The harmonized procedures and reference substances for the identification and assay of active metabolites in HMPs must be implemented at all stages of production control from herbal substances to finished dosage forms.