Development of approaches to standardization of bark of Syringa vulgaris L

Relevance. The relevance of carrying out chemical and pharmaceutical studies of the Syringa vulgaris L. bark is due to the fact that, despite the biological activity and the use as a source of the state reference standard of syringin, this plant material is not included in the State Pharmacopeia of the Russian Federation of the XIV edition. Purpose of the study. Development of methods for the qualitative and quantitative analysis of biologically active compounds in Syringa vulgaris L. bark. Material and methods. The objects of the study were samples of Syringa vulgaris L. bark, harvested in 2018-2020 in the Samara and Saratov regions, reference standard of syringin with a purity of at least 98%, as well as an experimental preparation "Syringa vulgaris L. tincture". In the study there were used the methods of thin layer chromatography (TLC) (solvent system chloroform-ethanol-water (26:16:3)) and high performance liquid chromatography (HPLC) (mobile phase - acetonitrile: 1% solution of acetic acid in water in the ratio 15:85). The syringin content was calculated using the external standard method. Results. The presence of syringin in the studied samples was confirmed by TLC. A method has been developed for the quantitative determination of syringin in the bark of Syringa vulgaris L. by microcolumn HPLC. The error of a single determination of the syringin content with a confidence level of 95% was ±3.20%. It was determined that the optimal parameters for the extraction of syringin are: a single extraction with 70% ethyl alcohol on a boiling water bath for 60 minutes in the ratio "raw material-extractant" - 1:30. The content of syringin in the studied bark samples varied from 2.55% to 5.38%. The proposed method was applied to determine the content of syringin in experimental preparations from the bark of Syringa vulgaris L. The error of a single determination of the syringin content in the Syringa vulgaris L. tincture with a confidence level of 95% was ±4.44%. Conclusion. The possibility of using thin layer chromatography for identification of the bark of Syringa vulgaris L. is shown. Results of the conducted studies have shown satisfactory metrological characteristics of the HPLC method for determining the quantitative content of syringin.

Syringa vulgaris L, Syringa vulgaris L, bark, syringin, microcolumn high-performance liquid chromatography