Phenolics content, in vitro antioxidant and anticholinesterase activities of combined berry extracts

Plant exfracts are often incorporated into food products, mainly due to their protective effects such as antioxidant or antimicrobial. Usually, individual extracts were used for such purposes. The aim of the present study was to investigate different combinations of bilberries-blackcurrants extracts as synergistic formulations in terms of phenolic compounds content, antioxidant and anticholinesterase activities. Different behaviours such as additive, synergistic and antagonistic effects were noticed in combined exfracts. With respect to antioxidant activity as measured by phenolics and FRAP assays, synergistic effects were observed in all tested combinations. The in vitro screening for acetylcholinesterase inhibition indicated inhibitory activity of combined extracts with different efficacies. The most promising formulation intended for antioxidant potential and pharmaceutical interest as well, was found to be 33% bilberry and 67% blackcurrant: 100 g of this freeze-dried formulation contains 2792 mg phenolics (1985 mg flavonoids, 1309 mg anthocyanins) and 3072 mg ascorbic acid equivalents (total antioxidant activity by FRAP). It can be considered a valuable starting point for the development of nutritional supplements or ingredients for food industry.