University of Guilan Caspian Journal of Environmental Sciences 1735-3033 23 4 2025 10 01 Comparative study of the composition and biological activity of polyphenols of currants, raspberries and strawberries 903 910 9207 10.22124/cjes.2025.9207 EN Zhanar Botbayeva Department "Technology and standardization", JSC "K. Kulazhanov kazakh university of technology and business», Astana, Kazakhstan Gulzhan Assemova Department "Microbiology and virology named after Sh. Sarbasova”, NJSC "Medical University Astana”, Astana, Kazakhstan Botbayeva Madina Department "Microbiology and virology named after Sh. Sarbasova”, NJSC "Medical University Astana”, Astana, Kazakhstan Bissimbayeva Saliya Laboratory of the first city hospital, R. Koshkarbaev, Astana, Kazakhstan Duissebekova Gulbanu Department "Microbiology and virology named after Sh. Sarbasova”, NJSC "Medical University Astana”, Astana, Kazakhstan Sarsenova Aigerim Department "Microbiology and virology named after Sh. Sarbasova”, NJSC "Medical University Astana”, Astana, Kazakhstan Moldasheva Elmira Department of Chemistry and Chemical Technology, K. Zhubanov Aktobe Regional University, Aktobe, Kazakhstan Ainur Zheldybayeva Department of Food Biotechnology, Almaty Technological University, Almaty, Kazakhstan Journal Article 2025 11 21 Berry fruits are of great nutritional and medicinal importance due to their polyphenolic compounds. The current research provided a comparative study of the polyphenolic compounds and bioactive activities of three fruits, currants (grapes), raspberries and strawberries, cultivated in the Almaty region of Kazakhstan. Polyphenolic compounds were determined using high-performance liquid chromatography and antioxidant activity was determined using two assays, DPPH and FRAP, and also for the alpha-glucosidase and acetylcholinesterase enzyme inhibitory activities. Quantitative analysis indicated that there were significant differences in the polyphenolic profile of these fruits. Total polyphenol content in strawberry (520.6 mg g^-1 dry weight) was significantly higher than raspberry (452.8) and currant (385.5). Strawberries had a very high content of this compound, i.e., 223 mg/100 g dry weight of anthocyanins. Raspberries, however, had the highest content of ellagitannins (158.4 mg/100 g dry weight) and had the highest DPPH free radical inhibitory activity (IC₅₀ value of 38.5 μg mL^-1). Currants were also the richest in these compounds and had 1.151 mg/100 g dry weight of flavonols. In the enzyme inhibition test, raspberries were the most potent inhibitors of the enzymes alpha-glucosidase (IC₅₀ = 0.65 mg mL^-1) and acetylcholinesterase (IC₅₀ = 1.15 mg mL^-1). The results of this research clearly show that all these fruits possess a unique chemical fingerprint and hence have varying health-promoting potential, which can be utilized as a scientific basis for the development of targeted nutraceutical products. https://cjes.guilan.ac.ir/article_9207_1d5f6702c00714db7d7a454757974057.pdf