Biological Properties of Recently Described Wild Bramble Rubus oklejewiczii against the Species from Similar Niches

Abstract

The aim of this study was to compare the biological properties, such as antiviral, antibacterial, and antioxidant, of recently described pentaploid species Rubus oklejewiczii with tetraploid taxa growing in similar habitats including R. plicatus, R. gracilis, and R. wimmerianus. The antiviral potential was analyzed against bacteriophages with different genetic material: phi6 (a surrogate for the SARS-CoV-2 virus), T7, phiX174, and MS2. Antibacterial properties of fruit and leaf extracts were determined against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Salmonella enterica. The total phenolic content, as well as anthocyanins, ascorbic acid, pH, and antioxidant properties (FRAP and DPPH) were determined. R. oklejewiczii leaf extract was characterized by the weakest antibacterial and antiviral properties, which was closely correlated with the lowest content of polyphenolic compounds and antioxidant properties. The strongest biological properties were observed for R. wimmerianus leaves. Fruit extracts were characterized by lower phenolic content and antioxidant activities than leaves, with the lowest values observed for R. oklejewiczii extract. The antibacterial properties of fruit extracts were strongest for R. gracilis. The strongest antiviral potential was observed for R. oklejewiczii and R. wimmerianus fruit extracts against the bacteriophage phi6, which correlated with the lowest pH and the highest ascorbic acid content. The positive effect of the higher ploidy of R. oklejewiczii for most of the analyzed biological properties was not observed except for the antiviral potential of fruit extract. Due to its large and tasty fruits, this species seems to be very promising for cultivation and attractive for consumers, even though most of its biological properties were not any better compared to other examined tetraploid species.