Standardization parameters of modified extracts from Arctostaphylos uva-ursi L. leaves

Abstract

Topicality. 25 % of the Ukrainian population is prone to the urinary system diseases and 10 % has signs of kidney and bladder chronic diseases. Common bearberry (Arctostaphylos uva-ursi L.) leaves are one of the most well-known types of the medicinal plant raw material with the uroantiseptic and diuretic activity. The method of obtaining a decoction from bearberry leaves is well known, but this dosage form is non-standardized, poorly stored, and it is difficult to maintain the accuracy of dosing. Therefore, the development of standardized medicines based on bearberry leaves is a crucial task.Aim. To determine standardization parameters of modified dry extracts from Arctostaphylos uva-ursi L. leaves in accordance with the requirements of the State Pharmacopeia of Ukraine (SPhU) and develop a draft of quality control methods (QCM) for these substances.Materials and methods. The study subjects were dry extracts of bearberry leaves modified with cysteine, phenylalanine, valine, glycine and arginine. For the analysis of the extracts obtained the pharmacopoeial methods were used in accordance with the monographs of the SPhU “Common bearberry leaves”. Identification of biologically active substances (BAS) in the extracts was performed using TLC. The content of hydroquinone derivatives and flavonoids in the extracts was determined by the spectrophotometric method according to the SPhU.Results and discussion. As a result of the research conducted the QCM drafts were developed; and according to their requirements dry extracts of bearberry modified with cysteine, phenylalanine, valine, glycine and arginine were studied. The QCM drafts for dry extracts of bearberry were developed by the following indicators: description, solubility, identification (TLC: method A (hydroquinone derivatives), B (flavonoids) and C (amino acids)), loss on drying (not more than 10 %), residual amounts of organic solvents (ethyl alcohol not more than 1.0 %), heavy metals (not more than 100 ppm), microbiological purity, the content of hydroquinone derivatives (not less than 5 % calculated with reference to arbutin) and flavonoids (not less than 2 % calculated with reference to rutin)). All extracts met the requirements of the documentation developed.Conclusions. The QCM drafts for modified dry extracts of bearberry leaves have been developed; according to their requirements, 5 dry extracts modified with cysteine, glycine, valine, phenylalanine and arginine have been studied. The standardized extracts obtained are promising substances. They can be used for developing dosage forms of new medicines with the uroantiseptic, diuretic and hypoglycemic activity.