Peonidin Glycosides Research Articles

Characterisation of acylated anthocyanins from red cabbage, purple sweet potato, and Tradescantia pallida leaves as natural food colourants by HPLC-DAD-ESI(+)-QTOF-MS/MS and ESI(+)-MSn analysis.

Anthocyanins in red cabbage, sweet potato, and Tradescantia pallida leaves were characterised. A total of 18 non-, mono-, and diacylated cyanidins was identified in red cabbage by high performance liquid chromatography-diode array detection coupled to high-resolution and multi-stage mass spectrometry. Sweet potato leaves contained 16 different cyanidin- and peonidin glycosides being predominantly mono- and diacylated. In T. pallida leaves, the tetra-acylated anthocyanin tradescantin prevailed. The large proportion of acylated anthocyanins resulted in a superior thermal stability during heating of aqueous model solutions (pH 3.0) coloured with red cabbage and purple sweet potato extracts as compared to that of a commercial Hibiscus-based food dye. However, their stability was still outperformed by that of the most stable Tradescantia extract. Comparing vis spectra from pH 1-10, the latter had an additional, uncommon absorption maximum at approx. 585nm at slightly acidic to neutral pH values, yielding intensely red to purple colours.

Biomarkers of Berry Intake: Systematic Review Update.

Berries are rich in (poly)phenols, and these compounds may be beneficial to human health. Estimating berry consumption through self-reported questionnaires has been challenging due to compliance issues and a lack of precision. Estimation via food-derived biomarkers in biofluids was proposed as a complementary alternative. We aimed to review and update the existing evidence on biomarkers of intake for six different types of berries. A systematic literature search was performed to update a previous systematic review on PubMed, Web of Science, and Scopus from January 2020 until December 2022. Out of 42 papers, only 18 studies were eligible. A multimetabolite panel is suggested for blueberry and cranberry intake. Proposed biomarkers for blueberries include hippuric acid and malvidin glycosides. For cranberries, suggested biomarkers are glycosides of peonidin and cyanidin together with sulfate and glucuronide conjugates of phenyl-γ-valerolactone derivatives. No new metabolite candidates have been found for raspberries, strawberries, blackcurrants, and blackberries. Further studies are encouraged to validate these multimetabolite panels for improving the estimation of berry consumption.

Chemical Composition and Polyphenol Compounds of Vaccinium floribundum Kunth (Ericaceae) from the Volcano Chimborazo Paramo (Ecuador)

Mortiño (Vaccinium floribundum Kunth) is considered a “superfruit” due to its antioxidant capacity and possible health benefits. To date, there is no known study that addresses the biochemical characterization of mortiño berries from the paramo of the Chimborazo volcano (Ecuador). So, the aim of this research was to evaluate for the first time the effect of the stage of development of the mortiño berries (two stages) and environment of origin (three sampling areas) on fruit quality. Polyphenol compounds were identified by high-performance liquid chromatography (HPLC) coupled to electrospray ionization mass spectrometric (ESI-MSn) and quantified by high-performance liquid chromatography with a diode array detector (HPLC-DAD). Moreover, antioxidant properties (ABTS•+, and DPPH), sugar and organic acids, and minerals were examined. The main organic acids were quinic and citric acid, while glucose, fructose, sucrose, mannose, and sorbitol were the main sugars determined in the mortiño fruits. The main constituents of the mortiño berries included hydroxycinnamic acids (5-O-caffeoylquinic acid), flavonols (quercetin 3-hexoside, quercetin 5-hexoside, quercetin 3-pentoside, and quercetin-3-O-rhamnoside) and anthocyanins. Seven anthocyanins were identified: glycosides of cyanidin, delphinidin, petunidin, peonidin, and pelargonidin. The research confirms that the mortiño berries produced in the Ecuadorian paramo area are a valuable source of polyphenolics, rich in sugars and organic acids, and can be classified as a good source of microelements.

Comparative analysis of quality and nutritional traits from Lonicera caerulea (Honeyberry) cultivars and other berries grown in Scotland

AbstractLonicera caeruleabrix is a perennial shrub native to North America, Europe and Asia. It produces dark blue berries known as honeyberries or haskap berries which are produced commercially in several territories including Canada, Japan, Russia and Poland. Plants are suited to UK environments, but it is yet to be widely commercially developed in the UK. In the present work, quality and nutritional traits of six honeyberry cultivars grown in Scotland were compared with other commonly grown berry fruits (strawberry, raspberry, blueberry, blackberry, blackcurrant) to aid the identification of environmentally stable, high‐quality honeyberry cultivars suitable for UK cultivation. Differences were observed in fruit quality variables (soluble solids, titratable acidity and Brix/acid ratios) between honeyberry cultivars. Three of six cultivars examined exhibited notable variation in soluble solids dependent on harvest year with ‘Aurora’ and ‘Strawberry Sensation’ having consistently high oBrix values. Titratable acidity exhibited cultivar differences and there was limited variation over harvest years. ‘Aurora’ exhibited consistently high oBrix/titratable acidity ratio reflected by high glucose and fructose content. Honeyberry fruit had good nutritional profile relative to other soft fruits with higher polyphenol and anthocyanin content than strawberry, blueberry, blackberry and raspberry, manifested in greater antioxidant capacity. The major anthocyanins in aqueous honeyberry fruit extracts were cyanidin, pelargonidin and peonidin glycosides. These findings indicate that L. caerulea represents a crop suitable for UK cultivation capable of producing high quality fruit with a valuable nutritional profile relative to other soft fruits. Cultivars exhibit significant differences in fruit quality and nutritional profile as well as harvest consistency and growers should consider this when establishing new plantations.

Polyphenol-Enriched Extracts of Prunus spinosa Fruits: Anti-Inflammatory and Antioxidant Effects in Human Immune Cells Ex Vivo in Relation to Phytochemical Profile.

The fresh fruits of Prunus spinosa L., a wild plum species, are traditionally used for dietary purposes and medicinal applications in disorders related to inflammation and oxidative stress. This study aimed to investigate the phytochemical composition of the fruits in the function of fractionated extraction and evaluate the biological potential of the extracts as functional products in two models of human immune cells ex vivo. Fifty-seven phenolic components were identified in the extracts by UHPLC-PDA-ESI-MS3, including twenty-eight new for the analysed fruits. Fractionation enabled the enrichment of polyphenols in the extracts up to 126.5 mg gallic acid equivalents/g dw total contents, 91.3 mg/g phenolic acids (caffeoyl-, coumaroyl-, and feruloylquinic acids), 41.1 mg/g flavonoids (mostly quercetin mono-, di- and triglycosides), 44.5 mg/g condensed proanthocyanidins, and 9.2 mg/g anthocyanins (cyanidin and peonidin glycosides). The hydroalcoholic extract and phenolic-enriched fractions of the fruits revealed significant ability to modulate pro-oxidant, pro-inflammatory, and anti-inflammatory functions of human neutrophils and peripheral blood mononuclear cells (PBMCs): they strongly downregulated the release of reactive oxygen species, TNF-α, and neutrophils elastase, upregulated the secretion of IL-10, and slightly inhibited the production of IL-8 and IL-6 in the cells stimulated by fMLP, fMLP+cytochalasin B, and LPS, depending on the test. Correlation studies and experiments on the pure compounds indicated a significant contribution of polyphenols to these effects. Moreover, cellular safety was confirmed for the extracts by flow cytometry in a wide range of concentrations. The results support the traditional use of fresh blackthorn fruits in inflammatory disorders and indicate extracts that are most promising for functional applications.

Fruit quality trait discovery and metabolic profiling in sweet cherry genebank collection in Greece

The current study characterizes the physicochemical, sensory and bioactive compound traits of twenty-two sweet cherry accessions, namely breeding lines, landraces and modern cultivars, embodying the majority of Greek germplasm. The evaluated accessions differ in several quality traits including colour parameters and textural properties as well as sensory attributes, such as taste intensity and overall acceptance. Significant differences in primary metabolites, including fructose, glucose, sorbitol, malic acid were recorded among tested accessions. All genotypes were rich in polyphenols, primarily in quercetin-3,4-O-diglucoside, esculetin, rutin and neochlorogenic acid. An anthocyanins-related discrimination among accessions was also obtained based on cyanidin-3-O-rutinoside and peonidin glycosides content. Overall, the cultivars ‘Tsolakeika’ and ‘Bakirtzeika’ exhibited the higher consumer acceptance while the cultivars ‘Vasiliadi’ and ‘Tragana Edessis-Naousis’ and especially the breeding line ‘TxAg33’ contained high polyphenol levels. These results represent a valuable resource for future breeding efforts for sweet cherry cultivars with improved nutritional quality traits.

COMPONENT COMPOSITION OF FLAVONOID PIGMENTS AND FLOWER COLOR IN PRUNUS MIRA AND HYBRID CULTIVARS OF ORNAMENTAL PEACH

Background. Ornamental peaches are flowering trees with petals ranging in color from white and pale pink to purplered. Because peach suffers from fungal infections, Prunus mira Koehne is often used in breeding programs as a donor of resistance. It also impacts on other traits, including flower color. The aim of this work was to study the composition of flavonoid pigments in the flowers of parent plants and new ornamental peach cultivars originated from P. mira.Objects and methods. Four new cultivars developed at the Nikita Botanical Gardens and their parental forms – P. mira and 4 cultivars with the P. persica morphotype – were included in the study. Pigments were extracted with acidified ethyl alcohol from fresh petals and identified by HPLC analysis.Results. Twelve glycosides of cyanidin and peonidin in different combinations and 8 glycosides of kaempferol and quercetin were found in the petal samples. Among colored plants, the highest amount of flavonols (114 mg g-1) and the lowest amount of anthocyanins (0.46 mg g-1) were found in P. mira petals. Anthocyanins predominate in cultivars with purple-red petals (16 mg g-1). Much more flavonols (55– 88 mg g-1) and little anthocyanins (1.2–3.4 mg g-1) were accumulated in the purple-pink flowers of hybrid cultivars. This trend persisted in the cultivars from crosses with a white-flowered parent. Conclusion. The ratio of anthocyanins and flavonols in the peach flowers depends on the plant species and determines the petals’ intermediate colors and half-tones. Using P. mira in breeding programs provides opportunities for the development of cultivars with new shades of flower color.

Irradiation Effect on the Structural Properties of <i>Ipomoea batatas </i>L as a Function of Temperature and Time

Purple sweet potato (Ipomoea batatas L) contains high anthocyanin and peonidin glycosides which are useful as powerful natural antioxidants. Microwaves is an electric oven that use for heats and cooks food by exposing electromagnetic radiation produce thermal energy which was influenced to the composition and structural properties of food. In this study, the effect of microwave irradiation on the structural and bonding characteristic of Ipomoea batatas L have been analysis by X-ray diffraction (XRD and Fourier transform infra-red (FTIR), respectively. The composition and the crystallite size was decreases with increasing the temperature and the time of irradiation. The intensity of functional group FTIR spectra shows for 20 minutes irradiation indicated the time for breaking bond of hydroxyl group due to evaporation and re-arrangement of atomic bonding for >20 minutes irradiation. The result in this study as a guided for general public the time maximum irradiation by microwave in the processing Ipomoea batatas L without change the properties

Flower colour and flavonoid pigments composition of the petals in ornamental peach cultivars obtained by crossing with Prunus mira

Ornamental peaches are flowering trees with petals ranging from white and pale pink to purple red colour. Prunus mira is often used in breeding programs as a donor of powdery mildew and leaf curl resistance. It also impacts on other traits including flower colour. The aim of our work was to study the composition of the flavonoid pigments in flowers of 5 parents and 4 new ornamental peach cultivars, originated from P. mira. The pigments were extracted with acid alcohol from fresh petals and were detected by HPLC analysis. P. mira is characterized by white petals with a pale purple nuance. Hybrids from crosses of P. mira and cultivars with purple red and purple pink flowers petals have lighter petal colour than the parental cultivars. Hybrids from crosses of P. mira and albiflorum cultivars have a light purple pink flower. Chromatographic analysis demonstrated 12 glycosides cyanides and peonidin in different combinations and also 8 glycosides kaempferol and quercetin in the petal samples. Among coloured trees, the highest amount of flavonols (114 mg g‑1) and the lowest amount of anthocyanins (0.46 mg g(‑1)) were found in P. mira flowers. In contrast, in P. persica 'Manifiс' purple red flowers only 16 mg g(‑1) of anthocyanins and 2.5 mg g(‑1) of flavonols were detected. Much more flavonols (55-88 mg g(-1)) and a little anthocyanins (1.2-3.4 mg g(-1)) are accumulated in purple pink flowers of hybrid cultivars 'Lel', 'Mirafic' and 'Zhisele'. This trend is saved in crosses with a white flower parent, and that is why 'Solveig' hybrid petals are light purple pink. The diversity of colour shades is probably due to different proportions of cyanides and peonidin glycosides. Thus, the use of P. mira in breeding programs provides opportunities for creating cultivars with new shades of flower colour and higher resistance against fungal diseases.

Phenolic Accumulation in Hybrid Primrose and Pigment Distribution in Different Flower Segments

Detailed anthocyanin and flavonol profiles were investigated in three flower segments of four different hybrid primrose (Primula ×polyantha) cultivars, and individual compounds were identified using high-performance liquid chromatography (HPLC)/mass spectrometry system. Chlorophyll a and b and total carotenoids were evaluated spectrophotometrically in the corolla tube (CT), and distal and proximal flower segments, and the color of each segment was assessed with a colorimeter. Chlorophyll b predominated over chlorophyll a in all flower segments, and the highest total chlorophyll levels were found in the CTs. Sixteen different anthocyanins (glycosides of cyanidin, delphinidin, peonidin, petunidin, malvidin, and rosinidin) were identified in red, pink, and blue flower extracts. Distal segments of the red hybrid and proximal segments of the pink hybrid accumulated highest levels of total anthocyanins, and no red pigments were detected in yellow-flowered hybrid primrose. Six groups of flavonols (40 individual compounds in total) were detected in different flower segments of four hybrid primrose cultivars. Yellow primrose was characterized by the greatest diversity of flavonols as it contained four isorhamnetin, five kaempferol, six laricitrin, three myricetin, six quercetin, and six syringetin glycosides. On the other hand, the smallest variety of flavonols was detected in pink hybrids. Total phenolic content (TPC) was lowest in the CT (yellow > red > pink), significantly higher in the proximal flower segment (yellow > red > pink), and highest in the distal part of the primrose petal (yellow > pink > red).

Combination of the anthocyanidins malvidin and peonidin attenuates lipopolysaccharide-mediated inflammatory gene expression in primary human adipocytes

We recently demonstrated that California table grapes and a methanol-extractable, polyphenol-rich fraction decreased adiposity, insulin resistance, or markers of inflammation in high-fat fed mice. Malvidin and peonidin glycosides were the 2 most abundant anthocyanins in the polyphenol-rich fraction. We hypothesized that a blood borne combination of anthocyanidins malvidin and peonidin derived from intestinal β-glycosidase metabolism of these 2 anthocyanins are responsible, in part, for the beneficial health effects observed in vivo. Therefore, we supplemented primary human adipocytes with malvidin or peonidin, alone or together, followed by acute lipopolysaccharide (LPS) treatment. Neither peonidin nor malvidin alone consistently decreased the expression of several inflammatory genes. However, supplementing adipocytes with an equal combination of malvidin plus peonidin followed by LPS treatment decreased the mRNA levels of interleukin (IL)-6, IL-1β, IL-8, monocyte chemoattractant protein-1, toll-like receptor-2, tumor necrosis factor alpha, cyclooxygenase-2, and interferon gamma-induced protein-10. The highest combination dose of malvidin plus peonidin decreased or increased the expression of protein tyrosine phosphatase-1B and hormone sensitive lipase, respectively, genes encoding proteins associated with insulin resistance or lipolysis. These data indicate that a combination of malvidin plus peonidin have potentiating interactions that reduce inflammatory gene expression; however, in vivo studies are needed to support these in vitro data.

Optimization of germination time and temperature to maximize the content of bioactive compounds and the antioxidant activity of purple corn (Zea mays L.) by response surface methodology

The objective of this study was to optimize germination time and temperature for maximizing the content of γ-aminobutyric acid (GABA), total phenolic compounds (TPC), and antioxidant activity in purple corn sprouts by using Response Surface Methodology (RSM). The phenolic composition of purple corn sprouts obtained in the optimal conditions was analyzed by HPLC-DAD-ESI/MS. Temperature of 26 °C and time of 63 h were found to be the optimal germination conditions since they enhanced 3.5-fold GABA content compared with seeds. These conditions, however, reduced ∼30 and ∼15% TPC and antioxidant activity, respectively, in purple corn. The models developed showed high coefficients of determination, demonstrating their adequacy to explain the variations in experimental data. Sprouts obtained in the optimal conditions presented anthocyanins as the most abundant phenolic class, detected mainly as cyanidin, pelargonidin, and peonidin glycosides or their malonyl derivatives. Hydroxycinnamic acids derivatives and flavonols were detected as minor compounds. Thus, germination at 26 °C for 63 h can be considered as an innovative strategy for diversifying the utilization of purple corn, providing at the same time sprouts with high levels of phytochemicals. Purple corn sprouts may constitute promising health-promoting foods.

Anthocyanin Profile in Berries of Wild and Cultivated Vaccinium spp. along Altitudinal Gradients in the Alps.

Vaccinium spp. berries provide some of the best natural sources of anthocyanins. In the wild bilberry (Vaccinium myrtillus L.), a clear increasing trend in anthocyanin biosynthesis has been reported toward northern latitudes of Europe, but studies related to altitude have given contradictory results. The present study focused on the anthocyanin composition in wild bilberries and highbush blueberry (Vaccinium corymbosum L. cv. Brigitta Blue) growing along altitudinal gradients in the Alps of northern Italy. Our results indicate an increasing accumulation of anthocyanins in bilberries along an altitudinal gradient of about 650 m. The accumulation was due to a significant increase in delphinidin and malvidin glycosides, whereas the accumulation of cyanidin and peonidin glycosides was not affected by altitude. Seasonal differences, especially temperature, had a major influence on the accumulation of anthocyanins in blueberries.

Anthocyanin composition of different wild and cultivated berry species

A broad range of anthocyanins (glycosides of cyanidin, pelargonidin, peonidin, delphinidin, malvidin, and petunidin) was identified and quantified in the fruit of 24 wild and cultivated berry species using HPLC-DAD-MS2. The anthocyanin composition in species of Ribes, Rubus, Vaccinium, and Fragaria genus as well as in less known species of Crataegus, Morus, Amelanchier, Sorbus, Sambucus and Aronia genus was determined. Cyanidin was the most commonly occurring anthocyanidin, meanwhile malvidin glycosides were only detected in blueberries. Glycosides of pelargonidin were detected in raspberries, strawberry, black mulberry and chokeberry. Peonidin glycosides were identified in hawthorn, black currant and gooseberry as well as in blueberry species. The richest species in the content of peonidin glycosides were blueberries. Delphinidin glycosides were the prevailing form of anthocyanins in black currant and bilberry. The highest total anthocyanin content was determined in dark colored fruit of cultivated elderberry and bilberry whereas light-colored dog rose and Chinese hawthorn fruit had the lowest anthocyanin content. The composition of anthocyanidin glycosides did not differ between the fruit of wild growing and cultivated species, but their contents were generally different.

Characteristic phenolic composition of the Greek variety Mavrokountoura grape and wine

Mavrokountoura, a clone of the Mandilaria grape cultivar, was studied for the first time. The morphological characteristics and composition of berries were determined, as well as total phenols and tannins in skins, flesh, and seeds. The skin anthocyanins were identified using HPLC-MS/MS and quantified using HPLC-DAD. Two main anthocyanins were identified as malvidin-3-O-glucoside and malvidin-3-O-(6″-p-coumaroyl)-glucoside. One minor anthocyanin was identified as malvidin-3-O-(6″-acetyl)-glucoside. Glycosides of delphinidin, petunidin, and peonidin were detected in traces. Young Mavrokountoura wine was also studied. Extraction of total phenols from the grape to the young wine amounted to 32%, composing mainly non-tannic phenols. The individual anthocyanin components exhibited different extractability values from the skin to wine, ranging between 10–94%.

Diversity of Phenolic Profiles in the Fruit Skin of Prunus domestica Plums and Related Species

The fruits of the European plum Prunus domestica exhibit a great diversity in appearance including skin colors. This study attempts to elucidate the phenylpropanoid and flavonoid profiles of 28 plum varieties belonging to P. domestica and related species as well as hybrids. A total of 49 phenolic compounds extracted from the fruit skin were quantitatively evaluated in an HPLC-DAD-based metabolomic study. The total phenolic contents of the cultivars varied among 0.4-29.9 mg/g fresh weight. The predominant anthocyanins were glycosides of cyanidin and peonidin, and rutin was the principal flavonol, whereas neochlorogenic acid and n-chlorogenic acid were the main hydroxycinnamic acids. Aside from these major phenolic classes, a group of tentatively identified flavones and several acylated flavonoids were also found. Principal component analysis revealed that anthocyanins and hydroxycinnamic acids contributed most to variety separation. The heterogeneity between the different varieties was also assessed using hierarchical cluster analysis of sample phenolics profile. A simple separation of species could not be found confirming the close relationship among them.

Triacylated peonidin 3-sophoroside-5-glucosides from the purple flowers of Moricandia ramburii Webb.

Triacylated peonidin 3-sophoroside-5-glucosides were isolated from the purple flowers of Moricandia ramburii Webb. (Family: Brassicaceae), and determined to be peonidin 3-O-[2-O-(2-O-(trans-feruloyl)-glucosyl)-6-O-(trans-p-coumaroyl)-glucoside]-5-O-[6-O-(malonyl)-glucoside] (1), peonidin 3-O-[2-O-(2-O-(trans-feruloyl)-glucosyl)-6-O-(cis-p-coumaroyl)-glucoside]-5-O-[6-O-(malonyl)-glucoside] (2) and peonidin 3-O-[2-O-(2-O-(trans-sinapoyl)-glucosyl)-6-O-(trans-p-coumaroyl)-glucoside]-5-O-[6-O-(malonyl)-glucoside] (3), respectively, by chemical and spectroscopic methods. In addition, one known acylated cyanidin glycoside, cyanidin 3-O-[2-O-(2-O-(trans-feruloyl)-glucosyl)-6-O-(trans-p-coumaroyl)-glucoside]-5-O-[6-O-(malonyl)-glucoside] (4), was also identified in the flowers. Peonidin glycosides have not been reported hitherto in floral tissues in to Brassicaceae.

Pharmacokinetics of cranberry juice anthocyanins, flavonols, flavanols, and phenolic acids in urine

Phenolic acids and flavonoids in cranberries may account for some of their putative health benefits. We have previously characterized the plasma pharmacokinetics of phenolic acids (including sinapic, homovanillic, protocatechuic, and sinapic acids) and flavonols (including kaempferol, myricetin, and quercetin) in 10 healthy adults, 50–70 y old. After a 2-d run-in period following a low polyphenol diet, fasted subjects consumed 237 mL low-calorie, sugar-free cranberry juice cocktail (54% juice). To determine the pharmacokinetics of cranberry bioactives in urine, samples were collected at 0, 2, 4, 6, 8, 10, and 24 h after beverage consumption for determination of 13 phenolic acids, 2 flavanols, 3 flavonols, 6 anthocyanins, and 7 anthocyanin glucuronides. The maximal urinary concentration (Cmax) and time to reach Cmax (Tmax) among the cranberry cyanidin and peonidin glycosides were 0.2–0.9 ng/mg creatinine at 2.2–3.4 h. The Cmax and Tmax of 4 cyanidin glucuronides and 3 peonidin glucuronides were 0.9–41.1 ng/mg at 3.0–5.1 h, respectively. The variations in Cmax and Tmax for phenolic acids and other flavonoids were more pronounced with concentrations of 0.1–21.1 μg/mg at 3.8–18.8 h, respectively. These data suggest that cranberry phenolic acids and flavonoids are bioavailable and metabolized in healthy older adults. (Supported by USDA and Ocean Spray, Inc.)

Antioxidant Capacity, Anthocyanin Content Profile in ‘Bluecrop’ Blueberry Fruit

Antioxidant Capacity, Anthocyanin Content Profile in ‘Bluecrop’ Blueberry Fruit Mature ‘Bluecrop’ berries, with no visible damage on the fruit surface, were picked by hand and placed in a common cold storage (as control) and under CA conditions consisting of 8 different CO2:O2 ratios (12:1.5, 12:3, 12:6, 12:12 and 18:1.5, 18:3, 18:6, 18:12) at 0°C. HPLC was used to separate and determine individual anthocyanin compounds in blueberry fruit. ‘Bluecrop’ blueberries contained 14 anthocyanins: glycosides of delphinidin, cyanidin, peonidin, petunidin and malvidin all with sugar bound at the 3-position. Generally, the content of anthocyanin compounds in fruit was the highest after 2 or 4-week storage. Total anthocyanin content was significantly higher in berries stored under CA condition, especially under low oxygen concentration, as compared with those placed in common cold storage, and CO2 concentration does not have any effect. Antioxidant activity strongly correlated with total anthocyanin content, delphinidin-3-glucoside, delphinidin-3-galactoside, delphinidin-3-arabinoside, petunidin-3-glucoside, petunidin-3-galactoside and with firmness, but slightly correlated with soluble solids and titratable acidity.

Red and purple coloured potatoes as a significant antioxidant source in human nutrition - a review

Potatoes regarding their consumption are a significant antioxidant source in human nutrition. The main potato antioxidants are polyphenols, ascorbic acid, carotenoids, tocopherols, -lipoic acid, and selenium. The most contained polyphenolic antioxidants in potatoes are L-tyrosine, caffeic acid, scopolin, chlorogenic and cryptochlorogenic acid and ferulic acid. In red and purple potatoes are in addition contained acylated anthocyanins and pigmented potatoes display two to three times higher antioxidant potential in comparison with white-flesh potato. Red potato tubers contain glycosides of pelargonidin and peonidin, purple potatoes glycosides of malvidin and petunidin. New red and purple flesh potato varieties are breeded for their use in food and in the non-food industry. Anthocyanins of potatoes are also useful in the protection against potato blight.