ELABORATION OF APPROACHES TO STANDARDIZING WILD BERGAMOT (MONARDA FISTULOSA L.) HERB

Introduction. Wild bergamot (Monarda fistulosa L.) is a North American species of the plant of the family Lamiaceae. The relevance of the study of wild bergamot is due to the high bactericidal effect exceeding that of some antibiotics. In addition, the wild bergamot raw material has anti-inflammatory, fungicidal, anthelmintic, antispasmodic, immunomodulatory, and antiseborrheic activities. Despite a variety of pharmacological effects, the wild bergamot raw material is not pharmacopoeial in both Russia and foreign countries. For introduction of wild bergamot herb into the State Pharmacopoeia of the Russian Federation, it is necessary to conduct a set of pharmacognostic studies, including the development of regulatory documentation confirming the quality of medicinal plant raw material. Objective: to develop a procedure for the quantitative determination of the amount of flavonoids in the wild bergamot herb. Material and methods. The object of the investigation was wild bergamot herb harvested in the Samara University Botanical Garden in July 2016–2018. The UV spectra of its extracts were spectrophotometrically measured and obtained on a Specod 40 spectrophotometer (Analytik Jena, Germany). Results. A procedure was developed to quantify the amount of flavonoids in the wild bergamot herb with the differential spectrophotometric method using the state standard sample of cynaroside at an analytical wavelength of 394 nm. The error of a measurement at a 95% confidence interval is ±2.23%. The developed procedure was used to analyze a number of wild bergamot herb samples. The amount of flavonoids in the raw material samples ranged from 3.92±0.4% to 4.28±0.1% (in terms of cynaroside). Conclusion. A spectrophotometric method for quantifying the amount of flavonoids was proposed for the standardization of wild bergamot herb. The flavonoid amount of less than 3.0% was recommended as the lower limit.