Antioxidant activity and anti-inflammatory effect of fruit extracts from blackcurrant, chokeberry, hawthorn, and rosehip, and their mixture with linseed oil on a model lipid membrane

The study of ethanol extracts as potential dietary supplements has shown that extracts of chokeberry (IC50 24.6 mu g/mL) and, to a lesser extent, blackcurrant, rosehip, and hawthorn (IC50 30.9, 33.5, and 45.9 mu g/mL) are good antioxidants in relation to UVB-oxidized phosphatidylcholine liposomes. All tested fruit extracts protect the bilayer against oxidation by reducing fluidity of the membrane hydrophilic/hydrophobic region (in the presence of extracts the generalized polarization of the Laurdan probe and fluorescence anisotropy of DPH and TMA-DPH increased). The major phenolic compounds were analyzed by high-performance liquid chromatography-mass spectrometry (HPLC/MS). The extracts caused inhibition of the pro-inflammatory enzymes cyclooxygenase-1 and cyclooxygenase-2, the highest for blackcurrant (77.6 and 70.5%, respectively) and rosehip (64.9 and 72.5%). Another aspect of the research demonstrated antioxidant and antiradical stability of the extracts during 12-month storage. With the exception of hawthorn, they stabilized the profile of unsaturated fatty acids of linseed oil during storage. The investigated fruit extracts in combination with polyunsaturated fatty acids may provide stable and effective dietary anti-inflammatory and antioxidant benefits. Practical applications: By combining two different groups of bioactive compounds (fruit extracts + omega-3 fatty acids), a new attractive product has been obtained of broad biological activity, which could potentially be useful as a functional food ingredient. The study enabled us to specify the regions where fruit extracts become imbedded in the membrane, based on changes in physical parameters induced in the regions, and will allow us to explain at the molecular level a possible way to protect lipid membranes against attack by free radicals.