Antioxidant properties of saskatoon berry (Amelanchier alnifoliaNutt.) fruits

Introduction. Saskatoon berry (Amelanchier alnifolia Nutt.) is a promising fruit species originating from North America. Among pomaceous fruits, saskatoon berries are a valuable source of chemical compounds with an antioxidant effect. Materials and methods. The total phenolic content, total flavonoid content and their correlation associated with the total antioxidant capacity of fruit of five particular cultivars were ascertained. Reactive oxygen species (specifically nitric oxide, superoxide anion and hydroxyl radical) and antioxidant activity in the liver lipid system of their methanolic extracts were also assessed. Results and discusssion. In saskatoon berry cultivars the total contents of phenolic compounds ranged from (2.52 to 3.82) g gallic acid Eq·kg–1 of fresh mass, while the values of total antioxidant capacity were observed to be from (4.17 to 5.29) g of ascorbic acid Eq·kg–1 of fresh mass. High correlation coefficients between phenolics as well as flavonoids and antioxidant capacity were calculated (r2 = 0.8921 and r2 = 0.9901, respectively). Nitric oxide, superoxide anion, hydroxyl radical and antioxidant activity in the liver lipid system of saskatoon berry fruit methanolic extracts (10%) were provided for the first time. In the case of nitric oxide, the inhibitions were 21.08–27.52%; as regards superoxide anion, they were 25.14–30.73%; concerning hydroxyl radical, 18.25–21.18%, and in respect of antioxidant activity in the liver lipid system, 7.90–8.38%. These inhibitions are stronger than, e.g., in apples which are the most important species of pomaceous fruit worldwide. Conclusions. Saskatoon berry fruit could be a suitable supplement for modern human nutrition. Furthermore, our work contributes to the popularisation of this pomaceous species, with the focus on its potential in relation to high antioxidant strength.