Isolation of valuable substances from berry seeds and pomace by the green high-pressure methods, their evaluation and application in cosmetic creams

Abstract

Berry seeds and pomace generated as a by-product of fruit processing contain valuable nutrients and bioactive compounds; however, nowadays it is inefficiently recycled or even discarded as a waste. Valorisation of such by-products for the development of higher value ingredients would substantially increase the sustainability of the sector. For this purpose, green extraction methods with supercritical CO2 (SFE-CO2) and pressurized liquid (PLE) extraction with hydro-ethanol were consecutively applied to strawberry, blackberry and elderberry seeds and rowanberry pomace for the isolation of lipophilic and higher polarity substances. SFE-CO2 extracts were rich in unsaturated fatty acids (oleic, 10.76 − 23.25 %; linoleic, 39.11 −59.74 %; linolenic, 1.32 − 43.83 %), tocopherols (31 – 637 μg/g), phytosterols (1992 – 3775 μg/g), carotenoids (65.06 – 2147 μg β-carotene/g) and chlorophylls (27.95 – 130.4 μg/g). Anthocyanins (22.7 – 697.6 mg cyanidin-3-O-glucoside equivalents/100 g), flavonoids (2.75 – 7.43 mg quercetin eqv./g), proanthocyanidins (122.2 – 199.4 catechin monohydrate eqv./g), antioxidant and antibacterial properties were evaluated for the PLE extracts. The extracts were tested in cosmetic creams at 2 % concentrations and strawberry seed extracts were selected for the evaluation of cream properties. In general, PLE extract addition had slight effect on antioxidant properties and sun protection factor of creams. However, considering the presence of high value constituents both in the lipophilic and hydrophilic extracts and the studies showing the benefits of the use of these constituents in cosmetic products, it may be expected that the extracts may be promising ingredients in developing new natural cosmetic products, including cosmeceuticals. In addition, the extracts may be promising ingredients in the formulation of nutraceuticals.