The development of the method to quantify the amount of the flavonoids of Leonurus deminutus v. Krecz. Herb

Relevance. Representatives of the genus Leonurus are sources of important biologically active compounds (BAQ, including phenolic ones. In the flora of Central Siberia, a plant of folk medicine is widespread - Leonurus deminutus V. Krez. To introduce a medicinal plant into medical practice, standardization of its medicinal plant raw materials (MPRM) is required. Objective. The development of the method to quantify the amount of the flavonoids in the aerial part of L. deminutus and validation evaluation of the developed method. Material and methods. The object of the study was samples of aerial organs of L. deminutus collected during the blooming period in 2021 on the territory of the Irkutsk region (near the village of Ust-Ordynsky). Quantitative determination of the amount of flavonoids was carried out by differential spectrophotometry, optimal extraction conditions were selected, contributing to the maximum yield of flavonoids. Validation was carried out according to the requirements of the OFS.1.1.0012.15 of the State Pharmacopoeia of the Russian Federation of the XIV edition. Results. Optimal extraction conditions for the quantitative determination of flavonoids in L. deminutus herb: extractant - ethyl alcohol 70%, the degree of grinding of raw materials - 1 mm, the ratio of "raw materials : extractant" - 1:100, extraction time - 60 minutes. When analyzing the extraction spectra, an analytical wave of 400±2 nm and a standard substance, cinaroside, were established. The relative error of the method was ±2,98%. Conclusion. The method to quantify the amount of the flavonoids in the aerial part of L. deminutus has been developed, a positive validation assessment of the developed method has been carried out. The validated method meets all the criteria of acceptability and can be recommended for inclusion in the regulatory documentation for this MPRM.