Comparative study of the composition and biological activity of polyphenols of currants, raspberries and strawberries

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 (۵۲۰.۶ mg g-۱ dry weight) was significantly higher than raspberry (۴۵۲.۸) and currant (۳۸۵.۵). Strawberries had a very high content of this compound, i.e., ۲۲۳ mg/۱۰۰ g dry weight of anthocyanins. Raspberries, however, had the highest content of ellagitannins (۱۵۸.۴ mg/۱۰۰ g dry weight) and had the highest DPPH free radical inhibitory activity (IC₅₀ value of ۳۸.۵ μg mL-۱). Currants were also the richest in these compounds and had ۱.۱۵۱ mg/۱۰۰ g dry weight of flavonols. In the enzyme inhibition test, raspberries were the most potent inhibitors of the enzymes alpha-glucosidase (IC₅₀ = ۰.۶۵ mg mL-۱) and acetylcholinesterase (IC₅₀ = ۱.۱۵ mg mL-۱). 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.

کلیدواژه ها:

Polyphenols ، Antioxidant activity ، Enzyme inhibition ، strawberry ، Raspberry