Sequential supercritical CO₂ and microwave-assisted extraction for dual valorization of berry pomace

In this study, redcurrant, blackcurrant, blueberry, and chokeberry pomace were valorized using supercritical CO₂ extraction (SC-CO₂) followed by microwave-assisted extraction of defatted residues. SC-CO₂ yielded 2.75-7.46% lipid fraction, rich in polyunsaturated fatty acids, mainly linoleic acid, with β-sitosterol as the predominant phytosterol. Redcurrant lipid fraction showed the highest tocopherol content. Chokeberry defatted pomace exhibited the highest total polyphenols, anthocyanins, and antioxidant capacity. UPLC-MS/MS identified over 40 phenolic compounds, with the highest anthocyanin content in chokeberry. Preliminary biological testing showed mild antioxidant and anti-inflammatory activity of chokeberry and blueberry extracts at 0.007-0.014 mg polyphenols/mL, while 0.5 mg polyphenols/mL was associated with cytotoxic effects. No clear genotoxic effects were observed for blueberry, blackcurrant, or redcurrant extracts, whereas chokeberry extract showed genotoxicity at higher concentrations. Overall, berry pomace emerged as a promising source of both lipophilic and hydrophilic bioactive fractions, with concentration- and cell-specific biological effects.