Analysis of the Content of Triterpene Saponins in the Buds and Leaves of Silver Birch (Betula Pendula Roth.)

Abstract

Plants of the Birch family are used in official and folk medicine. The buds and leaves of silver birch are used in the Russian Federation as a diuretic. Standardization of raw materials birch leaves is carried out in accordance with the requirements of FS .2.5.0005.15 “Birch leaves”, assessment of the quality of birch buds is carried out in accordance with FS 2.5.0006.15 “Birch buds”. To improve methods for quality control of birch buds and leaves, the authors proposed analyzing raw materials for the presence of a group of triterpene saponins. The study was carried out using raw materials - leaves and buds of silver birch, which were harvested from wild plants in environmentally safe areas of the Moscow region. The collection of raw materials was carried out in accordance with the recommendations of the relevant pharmacopoeial articles, as well as the “Instructions for collecting and drying birch buds.” Drying of silver birch leaves and buds was carried out using the air-shadow method. The dried raw materials were ground in an Ika analytical mill (Germany). Qualitative analysis was carried out with aqueous extracts from the analyzed raw materials using pharmacopoeial reagents used for the detection of saponins. The presence of triterpene saponins was established using qualitative reactions (foaming, with a solution of lead acetate, an alcohol solution of cholesterol, the Lafon reaction) in the leaves and buds of silver birch (Betula pendula Roth). The quantitative content of the amount of triterpene saponins in the studied raw materials in terms of oleanolic acid (CO Oleanolic acid analytical standard, AK Scientific, USA) was assessed by direct spectrophotometry on a Specord device at a wavelength of 310 nm. At the sample preparation stage, exhaustive extraction of the raw material was carried out with 70% ethyl alcohol. For the subsequent determination of aglycones of triterpene saponins, sample preparation included the stage of hydrolysis in a hydrolytic mixture obtained by mixing glacial acetic acid, concentrated hydrochloric acid (35-38%), distilled water in a volume ratio of 3.5: 1: 5.5, followed by heating in for 2.5 hours. It has been shown that the content of the sum of triterpene saponins in terms of oleanolic acid is 14.741% for buds, and 11.299% for leaves