Stability Studies of Bioactive Compounds from Birch Outer Bark Ethanolic Extracts

摘要

The literature survey summarizes information about birch outer bark major components: betulin, betulinic acid, lupeol, and ursolic acid. In the practical part of the research stability of birch outer bark major components against chemical and physical degradation was tested; total phenolic content and the antiradical activity of the degraded and nondegraded ethanolic extracts was studied using UV/VIS spectroscopy; the phytochemical composition of the birch outer bark ethanolic extract was investigated by HPLC-TOF/MS. The study of stability showed that compounds of birch outer bark ethanolic extract can be exposed to thermal and humidity degradation as well as to β radiation without decomposition in these degradation conditions. Acid or base degradation and oxidative degradation lead to partial degradation of the extracts. This kind of study for birch outer bark extract has not been described yet and will serve as a basis for determining the expiration date of cosmetic products and food additives containing the extract, the choice of the required product packaging and storage conditions.