Composition of biologically active substances of common cranberry fruits (Oxycoccus palustris Pers.) in various methods of preservation

Abstract

Introduction. The study of common cranberry fruits is promising due to the wide variety of biologically active substances included in their composition, a wide range of therapeutic properties, as well as the ability of cranberry fruits for long-term storage and resistance to harsh environmental conditions. Fresh fruits contain the maximum amount of biologically active substances and, accordingly, have the most pronounced pharmacological effect. To preserve the composition and content of biologically active substances, preservation is used in pharmacy. Most often they resort to drying. Freezing can be considered a new and promising method for preserving the quality of medicinal plant materials. Purpose of the study. Study of the effect of freezing and drying on the qualitative composition and quantitative content of biologically active substances in common cranberry fruits. Material and methods. The object of the study was fresh, frozen, and dried common cranberry fruits collected in the Pskov and Novgorod regions in 2022 during the fruiting period. The study of the composition of biologically active substances (BAS) and quantitative assessment of the content were carried out according to pharmacopoeial methods, using analysis using thin layer chromatography (TLC), spectrophotometry and redox titration methods. Results. Using TLC analysis, organic acids (ascorbic, malic, citric, tartaric and succinic), flavonoids (rutin, quercetin), tannins (gallic acid) and anthocyanins were identified in the fruits. There were no differences in the qualitative composition of dried and frozen fruits. The content of organic acids, tannins, flavonoids and anthocyanins in cranberry fruits using different preservation methods was determined. It has been established that when fruits are dried, the content of all studied groups of biologically active substances decreases, on average by 40–60% of the initial content in fresh raw materials. Ascorbic acid is destroyed to a greater extent (90–92%). Exposure to low temperatures leads to a slight decrease in biologically active substances in common cranberry fruits (7–14%). Conclusion. The influence of preservation methods on the composition and content of biologically active substances in common cranberry fruits has been studied. The possibility of using frozen cranberry fruits as an alternative to fresh and dried raw materials in the manufacture of drugs in allopathy and homeopathy has been shown.