Chromatography Assisted Validation of Alternate Plant Materials in a Polyherbal Formulation: A Prospective Positive Substitution

Introduction: Bergenia ligulata Wall. is a popular medicinal herb from family Saxifragaceae, belonging to category of medicinal plants, the authentic species of which are not available easily. Though Ayurvedic Formulary of India prescribes the use of Bergenia ligulata, manufacturers have been using different species of Bergenia in many traditional Ayurvedic formulations including Pushyanuga churna (PC). Commercial exploitation of Bergenia ligulata has resulted in imbalance between supplies of this plant drug as compared to its demand. Commercially therefore, Bergenia ciliata which is more abundantly available, is substituted for Bergenia ligulata. Methods: The present study was undertaken to validate the use of Bergenia ciliata in a polyherbal formulation (PC), as a positive substitute for Bergenia ligulata. One in-house PC containing B. ligulata, along with two commercially available formulations of PC containing different species of Bergenia were compared for their bergenin content using validated HPLC method to evaluate the phytochemical equivalence. Results: Bergenin content in the in-house formulation containing B. ligulata was found to be 0.27mg/gm whereas the commercial samples containing B. ciliata contained 0.24mg/gm of bergenin while another marketed formulation without label claim contained 0.162mg/gm of bergenin. The results clearly support the use of B. ciliata as a positive substitute for B. ligulata in PC. Conclusion: Positive substitution can be adopted by manufacturing units for the medicinal plant ingredients, which are scarcely available, to prevent their over-exploitation from the wild. Such substitutions can be justified if phytochemical equivalence could be demonstrated by validated chromatographic techniques. Nevertheless, evidence based efficacy studies need to be conducted additionally to corroborate such usage.