The results of this study confirm that vitamin C and flavonoids are responsible for the antioxidant activity of rosehip tea, while only polyphenols contribute to its antiproliferative activity.

Grape seed extracts (GSEs,) obtained from Italian and Rhine Rieslings, were examined for polyphenolic composition and antioxidant activities using HPLC and ESR spectrometry. The seed extraction was carried out with ethyl acetate and ethanol. The contents of polyphenols, flavan-3-ols and antioxidant activities were found to be higher in ethyl acetate than in ethanolic extracts. IC 50 values were 0.1045 mg/mL and 0.0599 mg/mL for the stable DPPH radical in ethanolic and ethyl acetate extracts, respectively. The values for the shortlived OH radical were 0.1989 mg/mL and 0.0362 mg/mL, in the given order. The significant correlations between the antioxidant activities of GSEs and polyphenols were established (P < 0.05). Owing to their antioxidant activities, the cultivars could be used as a source to produce a GSE.

Successful valorisation of raspberry and blueberry pomace was achieved through their application, as dried and ground powders, in the formulation of value-added glutenfree cookies. Simplex-lattice mixture design approach was applied to obtain the product with the best sensory properties, nutritional profile and antioxidant activity. The highest desirability of 90.0 % was accomplished with the substitution of gluten-free flour mixture with 28.2 % of blueberry and 1.8 % of raspberry pomace. The model was verified. Optimized cookies had similar protein (3.72 %) and carbohydrate (66.7 %) contents as gluten-containing counterparts used for comparison, but significantly lower fat content (10.97 %). Daily portion of the optimized cookies meets: 5.00 % and 7.73 % of dietary reference intakes (DRIs) for linoleic acid, 23.6 % and 34.3 % of DRIs for α-linolenic acid and 10.3 % and 15.6 % of DRIs for dietary fibers, for male and female adults, respectively. The nutritional profile of the optimized formulation makes it comparable with added-value glutencontaining counterparts.

Summary Antioxidant and antiproliferative activities of three rosemary extract formulations (VivOX 20, VivOX 40 and Inolens 50) with different contents of carnosic acid, carnosol and methylcarnosol were tested in vitro. Electron spin resonance measurements revealed that Inolens 50 extract that contained highest amount of carnosic acid was the most potent scavenger of hydroxyl (concentration of extract where 50% of its maximal scavenging activity is observed, that is, EC50, 109.54 μg mL−1), superoxide anion (EC50 = 7.94 μg mL−1) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) (EC50 = 27.4 μg mL−1)‐free radicals. Comparison of the radar charts of standard antioxidants and rosemary extracts showed similarity between antioxidant characteristics of Inolens 50 and chlorogenic and caffeic acids. Tested rosemary extracts exhibited significant (P ≤ 0.01) antiproliferative effect in cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT‐29) cell lines. In both MCF7 and HeLa cell lines, the extracts yielded very low IC50 values (concentration of extract needed to inhibit cell growth by 50%), the most pronounced being for Inolens 50 in MCF7 (IC50 = 9.95 μg mL−1) and VivOX 20 in HeLa cell line (IC50 = 10.02 μg mL−1). The obtained results may provide support for the use of tested rosemary extracts as nutraceuticals and phytopharmaceuticals.

Naturally occurring antioxidants present in bilberry were separated into three groups: vitamin C, phenolic acids and flavonoids using solid phase extraction (SPE). Chemical composition of bilberry extract fractions was obtained by spectrophotometry and high performance liquid chromatography (HPLC). The results of HPLC analysis point out the high content of vitamin C (1529 g/g) in fraction Fr1, flavonoids (1328.58 g/g) in fraction Fr2 and phenolic acids (494.31 g/g) in fraction Fr3. The free radical scavenging activities of these antioxidant fractions on superoxide anion radicals and detection of free radical intermediates was studied using electron spin resonance (ESR) spectroscopy. Superoxide anion free radical assay demonstrated very potent free radical scavenging activity of bilberry extract fractions. The results of correlation analysis showed that the separated classes of antioxidants from bilberry (vitamin C, flavonoids and phenolic acids) are responsible for its antioxidant activity.

This paper attempts to lead the reader an understanding of what free radicals are and how they can form during lipid oxidation. Also, it provides some information out natural antioxidants (tocopherols and tocotrienols flavonoids, polyphenols, tannines, melanoidihes, carotenoids, ascorbates) and the echanisms of their protection from radical damage. The sources of natural antioxidants are: oil seeds, teas, vegetables, fruits, spices and herbs

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Rose hip is a rich source of naturally occurring antioxidants. Its activity is mainly attributed to compounds represented by vitamin C and polyphenols. Rose hip extract was fractionated using solid phase extraction. Free radical scavenging activities of rose hip extract fractions containing vitamin C ( 39.17 µg/g dry rose hip), flavonoids (0.11 µg/g dry rose hip), and phenolic acids (0.50 µg/g dry rose hip) towards hydroxyl and superoxide anion radicals were evaluated using electron spin resonance spectroscopy. The presence of antioxidant derived free radical intermediates during reactions with superoxide anion radical was also observed. Very potent free radical scavenging activities of rose hip extract fractions, as well as good correlations with compositional data were revealed.