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1.
《Cereal Chemistry》2017,94(5):811-819
This study systematically examined hydrothermal effects of antioxidant substances, such as total phenolic (TPC), flavonoid (TFC), and proanthocyanidin (TPAC) contents, cyanidin‐3‐O‐glucoside (C3G), peonidin‐3‐O‐glucoside (P3G), α‐, γ‐, and δ‐tocopherols, and α‐, γ‐, and δ‐tocotrienols, as well as antioxidant activities, color parameters, and soluble sugar compositions in red and black rice. It showed that color differences (ΔE ) of black rice were higher than those of red rice caused by boiling. The processed red and black rice exhibited significantly (P < 0.05) lower TPC, TFC, TPAC, C3G, P3G, and antioxidant activities compared with the raw rice except bound TPC and bound antioxidant activity. Interestingly, soluble free p‐coumaric and ferulic acids had higher contents in cooked red rice, and soluble free protocatechuic, vanillic, and sinapic acids had higher contents in cooked black rice. Boiling caused significant decreases of soluble conjugated phenolic acids and significant increases of insoluble bound phenolic acids in both red and black rice. Increases of total free tocol, glucose, and fructose contents were observed in most red and black rice. To increase the contents of some soluble free and insoluble bound phenolic acids, free vitamin E, and monosaccharides in red and black rice, boiled rice might be a good choice.  相似文献   

2.
The effects of boiling and steaming processes on the phenolic components and antioxidant activities of whole yellow (with yellow seed coat and yellow cotyledon) and black (with black seed coat and green cotyledon) soybeans were investigated. As compared to the raw soybeans, all processing methods caused significant (p < 0.05) decreases in total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), monomeric anthocyanin content (MAC), DPPH free radical scavenging activity (DPPH), ferric reducing antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC) in black soybeans. Pressure steaming caused significant (p < 0.05) increases in TPC, CTC, DPPH, FRAP, and ORAC in yellow soybeans. The steaming resulted in a greater retention of TPC, DPPH, FRAP, and ORAC values in both yellow and black soybeans as compared to the boiling treatments. To further investigate the effect of processing on phenolic compounds and elucidate the contribution of these compounds to changes of antioxidant activities, phenolic acids, isoflavones, and anthocyanins were quantitatively determined by HPLC. The pressure steaming treatments caused significant (p < 0.05) increases in gallic acid and 2,3,4-trihydroxybenzoic acid, whereas all treatments caused significant (p < 0.05) decreases in two predominant phenolic acids (chlorogenic acid and trans-cinnamic acid), and total phenolic acids for both yellow and black soybeans. All thermal processing caused significant (p < 0.05) increases in aglucones and beta-glucosides of isoflavones, but caused significant (p < 0.05) decreases in malonylglucosides of isoflavones for both yellow and black soybeans. All thermal processing caused significant (p < 0.05) decreases of cyanidin-3-glucoside and peonidin-3-glucoside in black soybeans. Significant correlations existed between selected phenolic compositions, isoflavone and anthocyanin contents, and antioxidant properties of cooked soybeans.  相似文献   

3.
The influence of growing season (winter vs summer) on the synthesis and accumulation of phenolic compounds and antioxidant properties was studied in five grape cultivars for three consecutive years. Four phenolic compound parameters (total phenols, flavonoids, flavan-3-ols, and anthocyanins) and three antioxidant property parameters [2,2-diphenyl-1-picrylhydrazyl radical scavenging, 2,2-azinobis(3-ethylbenzothiazolinesulfonic acid) radical scavenging, and ferric reducing antioxidant power] were investigated. Results showed that both phenolic compounds and antioxidant properties in the seed and skin of winter berries were significantly (p < 0.05) higher than those of summer berries for all of the cultivars investigated. The anthocyanin profiles of berry skins appeared to be extremely consistent in different years for the same crop, whereas they varied greatly between the two crops within the same year (winter vs summer). Winter berries contained richer glucosides of delphinidin, cyanidin, peonidin, and malvidin than summer berries. These seasonal variations of phenolic compounds and antioxidant properties on grape berries were largely contributed by climatic factors such as temperature, solar radiation, rainfall, and hydrothermic coefficient between different growing seasons.  相似文献   

4.
This study investigated the in vitro and in vivo antioxidant and anti-inflammatory properties of a juice blend (JB), MonaVie Active, containing a mixture of fruits and berries with known antioxidant activity, including acai, a palm fruit, as the predominant ingredient. The phytochemical antioxidants in the JB are primarily in the form of anthocyanins, predominantly cyanidin 3-rutoside, cyanidin 3-diglycoside, and cyanidin 3-glucoside. The cell-based antioxidant protection of erythrocytes (CAP-e) assay demonstrated that antioxidants in the JB penetrated and protected cells from oxidative damage ( p < 0.001), whereas polymorphonuclear cells showed reduced formation of reactive oxygen species ( p < 0.003) and reduced migration toward three different pro-inflammatory chemoattractants: fmlp ( p < 0.001), leukotriene B4 ( p < 0.05), and IL-8 ( p < 0.03). A randomized, double-blinded, placebo-controlled, crossover trial with 12 healthy subjects examined the JB's antioxidant activity in vivo. Blood samples at baseline, 1 h, and 2 h following consumption of the JB or placebo were tested for antioxidant capacity using several antioxidant assays and the TBARS assay, a measure of lipid peroxidation. A within subject comparison showed an increase in serum antioxidants at 1 h ( p < 0.03) and 2 h ( p < 0.015), as well as inhibition of lipid peroxidation at 2 h ( p < 0.01) postconsumption.  相似文献   

5.
Anthocyanins and phenolics of 10 blue honeysuckle (Lonicera caerulea L.) genotypes were characterized and quantified by HPLC-DAD. Peak assignments were confirmed by low-resolution electrospray mass spectrometry. Six anthocyanins were detected with the major peak identified as cyanidin 3-glucoside. Five additional anthocyanins were characterized as cyanidin 3,5-diglucoside, cyanidin 3-rutinoside, pelargonidin 3-glucoside, peonidin 3-glucoside, and peonidin 3-rutinoside. Four polyphenolics were identified as chlorogenic acid, neochlorogenic acid, quercetin 3-rutinoside, and quercetin 3-glucoside. Two additional unidentified phenolics were characterized as flavonol and hydroxycinnamic derivatives based on UV-vis spectra. Hydroxycinnamate levels ranged from 30.4 to 156.2 mg/100 g, whereas the flavonol content ranged from 12.6 to 32.8 mg/100 g. The L. caerulea subspecies boczkarnikovae contained the highest amounts of hydroxycinnamic derivatives and flavonols.  相似文献   

6.
Anthocyanins from blood orange [Citrus sinensis (L.) Osbeck] juices were isolated and purified by means of high-speed countercurrent chromatography and preparative high-performance liquid chromatography. Structures of the pigments were then elucidated by electrospray ionization multiple mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The major anthocyanins of the juice were characterized as cyanidin 3-glucoside and cyanidin 3-(6"-malonylglucoside). Furthermore, six minor anthocyanins were detected and identified as cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-sophoroside, delphinidin 3-(6"-malonylglucoside), peonidin 3-(6"-malonylglucoside), and cyanidin 3-(6"-dioxalylglucoside). The occurrence of the latter compound in blood oranges is reported here for the first time, together with full NMR spectroscopic data. Further investigations revealed the presence of four anthocyanin-derived pigments, which are formed through a direct reaction between anthocyanins and hydroxycinnamic acids during prolonged storage of the juice. These novel pyranoanthocyanins were identified as the 4-vinylphenol, 4-vinylcatechol, 4-vinylguaiacol, and 4-vinylsyringol adducts of cyanidin 3-glucoside through comparison of their mass spectrometric and chromatographic properties with those of synthesized reference compounds.  相似文献   

7.
Flowers of maize, Zea mays, and reed canarygrass, Phalaris arundinacea, contain the same anthocyanins: cyanidin 3-glucoside, cyanidin 3-(6' '-malonylglucoside), cyanidin 3-(3' ',6' '-dimalonylglucoside), peonidin 3-glucoside, peonidin 3-(6' '-malonylglucoside), and peonidin 3-(dimalonylglucoside). The latter pigment has previously not been reported to occur in plants. Structure elucidations were primarily based on homo- and heteronuclear two-dimensional NMR and electrospray MS. During the isolation procedure using various mixtures of H(2)O, CF(3)CO(2)H, and CH(3)OH, and during storage in NMR solvent (CF(3)CO(2)D/CD(3)OD; 1:19, v/v) methyl esterification of the free acid function of the malonyl units of the pigments occurs. The acylated anthocyanins constitute more than 80% and 40% of the anthocyanins in P. arundinacea and Z. mays, respectively. Flowers and leaves of maize, Zea mays, contain the same anthocyanins in nearly equal relative proportions.  相似文献   

8.
Anthocyanin constituents in black raspberries (Rubus occidentalis L.) were investigated by HPLC-DAD, and their involvement as potent, significant antioxidants in black raspberries was demonstrated by three common antioxidant assays (FRAP, DPPH, ABTS) in this study. Five anthocyanins were present in black raspberries: cyanidin 3-sambubioside, cyanidin 3-glucoside, cyanidin 3-xylosylrutinoside, cyanidin 3-rutinoside, and pelargonidin 3-rutinoside. Their identities and structures, with particular emphasis on cyanidin 3-xylosylrutinoside, were confirmed by NMR spectroscopy. Two of these anthocyanins, cyanidin 3-rutinoside and cyanidin 3-xylosylrutinoside, predominated, comprising 24-40 and 49-58%, respectively, of the total anthocyanins in black raspberries. On the basis of both potency and concentration, cyanidin 3-rutinoside and cyanidin 3-xylosylrutinoside were found to be the significant contributors to the antioxidant systems of black raspberries. These findings indicate that these two anthocyanin compounds may function as the primary phenolic antioxidants in black raspberries. These two compounds exhibit potential biological activities that may be exploited in conjunction with other naturally occurring bioactive compounds in black raspberry fruit-based products used in clinical trials for the treatment of various types of cancer.  相似文献   

9.
Barley and its products are good sources of antioxidants. This experiment was conducted to examine the classification and concentration of phenolic compounds, proanthocyanidins, and anthocyanins in 127 lines of colored barley. Their relationship with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was also examined. Barley was placed into seven groups using the colorimeter: hulled (black 1, black 2, black 3, and purple) and unhulled (black, blue, and purple). The contents of phenolic compounds and anthocyanins were analyzed by using HPLC. The average content of phenolic compounds in unhulled barley groups (268.6 microg/g) was higher than that in hulled (207.0 microg/g) (P > 0.05). The proanthocyanidins content was determined by modified vanillin assay. The average content of proanthocyanidins was significantly higher in purple and blue barley groups compared with black (P < 0.05). The content of anthocyanins varied from 13.0 to 1037.8 microg/g. Purple and blue barley groups contained higher average contents of anthocyanins than black (P < 0.05). The most common anthocyanin in the purple barley groups was cyanidin 3-glucoside, whereas delphinidin 3-glucoside was the most abundant anthocyanin in the blue and black groups. In colored barley, DPPH radical scavenging activity had high positive correlation to the content of phenolic compounds and proanthocyanidins.  相似文献   

10.
Anthocyanin pigments from a wide variety of edible and ornamental black, blue, pink, purple, red, and white wheat, barley, corn, rice, and wild rice were identified and quantified to evaluate their potential as natural colorants or functional food ingredients. The total anthocyanin contents varied significantly and exhibited a range of 7-3276 microg/g. Some grains, such as red rice and black rice, contained a limited number of pigments, whereas others, such as blue, pink, purple, and red corns, had complex anthocyanin profiles. Of the 42 anthocyanin compounds observed, 9 were characterized by comparison of the spectroscopic and chromatographic properties with those of authentic standards. The remaining compounds were tentatively identified on the basis of spectroscopic properties and electrospray ionization mass spectra. The most abundant anthocyanins were cyanidin 3-glucoside in black and red rices and in blue, purple, and red corns, pelargonidin 3-glucoside in pink corn, and delphinidin 3-glucoside in blue wheat.  相似文献   

11.
This study evaluated the protective effects of purple rice ( Oryza sativa L.) bran extract (PRE) and its major anthocyanidins (cyanidin and peonidin) against light-induced retinal damage. In an in vitro experiment, cultured murine photoreceptor cells (661W) were damaged by a 24 h exposure to light. Viability of 661W after light treatment, assessed by the tetrazolium salt (WST-8) assay and Hoechst 33342 nuclear staining, was improved by the addition of PRE, cyanidin, and peonidin. Intracellular radical activation in 661W, evaluated using the reactive oxygen species (ROS) sensitive probe 5-(and 6)-chloromethyl-2,7-dichlorodihydrofluorescein diacetate acetyl ester (CM-H(2)DCFDA), was reduced by PRE and its anthocyanidins. Electron spin resonance (ESR) measurements showed that PRE, peonidin, and cyanidin all exhibited radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide anion radical ((?)O(2)(-)), and hydroxyl radical ((?)OH). In an in vivo mouse experiment, intravitreous injection of PRE significantly suppressed photoreceptor degeneration induced by exposure to light as revealed by histological analysis using hematoxylin-eosin staining. These findings suggest that PRE and its anthocyanidins possess protective effects with antioxidation mechanism in both in vitro and in vivo models of retinal diseases.  相似文献   

12.
Black soybeans have been used as an excellent dietary source for disease prevention and health promotion in China for hundreds of years. However, information about the distribution of health-promoting phenolic compositions in different physical parts of black soybean and the contribution of phenolic compositions to overall antioxidant capacity is limited. To elucidate the distribution of phenolic composition and their contribution to antioxidant activities in black soybean, the total and individual phenolic profiles, and antioxidant capacities of seed coat, dehulled and whole black soybean were systematically investigated. The seed coat exhibited much higher total phenolic indexes and antioxidant activities than whole and dehulled black soybean. Dehulled black soybean possessed similar levels of total phenolic content, total flavonoid content, 2-diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) activities as compared to whole yellow soybean. Cyanidin-3-glucoside, petunidin-3-glucoside, and peonidin-3-glucoside were detected in the seed coat but not in dehulled black soybean and yellow soybean. Among benzoic acid detected, caffeic and chlorogenic acid were the predominant phenolic acids. Whole black soybean and dehulled black soybean exhibited similar isoflavone contents in 7- O-beta-glucosides and malonylglucosides of daidzein and genistein. The seed coat possessed significantly ( p < 0.05) lower 7- O-beta-glucosides and malonylglucosides of daidzein and genistein, acetylglycitin, and total isoflavones than whole and dehulled black soybean. The contribution of phenolics in the seed coat to the antioxidant activity of black soybean parts depends on the assay methods. When measured with the DPPH and FRAP methods, the seed coat contributed 90% of the total antioxidant capacity of black soybean. However, when measured with the ORAC method, the seed coat and dehulled portion contributed approximately equally the total antioxidant capacity of black soybeans. The information generated from this study on the distribution and content of their active components is useful for the effective use of black soybeans as an ingredient for promoting health.  相似文献   

13.
In the skin of cv. Napoleon table grapes, the anthocyanins malvidin 3-glucoside (and its acetyl and p-coumaroyl derivatives), cyanidin 3-glucoside, peonidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, and delphinidin 3-glucoside were identified by HPLC-DAD-MS. In addition, quercetin 3-glucoside and 3-glucuronide, caffeoyltartaric, piceid, and resveratrol were also detected. The content of most phenolics remained quite constant during postharvest refrigerated storage (10 days at 0 degrees C) while the resveratrol derivatives increased 2-fold. Postharvest treatments of grapes with UVC and UVB light induced a large increase in resveratrol derivatives (3- and 2-fold, respectively). This means that a serving of mature Napoleon grapes (200 g) provides approximately 1 mg of resveratrol, which is in the range of the amount supplied by a glass of red wine. This can be increased to 2 or 3 mg of resveratrol per serving in grapes that have been irradiated with UVB or UVC, respectively. These results show that refrigerated storage and UV irradiation of table grapes can be beneficial in terms of increasing the content of potentially health-promoting phenolics.  相似文献   

14.
Flavonoids have been reported to lower oxidative stress and possess beneficial effects on cardiovascular diseases and chronic inflammatory diseases associated with nitric oxide (NO). Common phenolic compounds, including phenolic acids, flavonols, isoflavones, and anthocyanins, present in fruits were investigated for their effects on NO production in LPS/IFN-gamma-activated RAW 264.7 macrophages. Phenolic compounds at the range of 16-500 microM that inhibited NO production by > 50% without showing cytotoxicity were the flavonols quercetin and myricetin, the isoflavone daidzein, and the anthocyanins/anthocyanidins pelargonidin, cyanidin, delphinidin, peonidin, malvidin, malvidin 3-glucoside, and malvidin 3,5-diglucosides. Anthocyanins had strong inhibitory effects on NO production. Anthocyanin-rich crude extracts and concentrates of selected berries were also assayed, and their inhibitory effects on NO production were significantly correlated with total phenolic and anthocyanin contents. This is the first study to report the inhibitory effects of anthocyanins and berry phenolic compounds on NO production.  相似文献   

15.
This study investigated the antioxidant content and activity of phenolic acids, anthocyanins, α-tocopherol and γ-oryzanol in pigmented rice (black and red rice) brans. After methanolic extraction, the DPPH free radical scavenging activity and antioxidant activity were measured. The pigmented rice bran extract had a greater reducing power than a normal rice bran extract from a long grain white rice. All bran extracts were highly effective in inhibiting linoleic acid peroxidation (60-85%). High-performance liquid chromatography (HPLC) analysis of antioxidants in rice bran found that γ-oryzanol (39-63%) and phenolic acids (33-43%) were the major antioxidants in all bran samples, and black rice bran also contained anthocyanins 18-26%. HPLC analysis of anthocyanins showed that pigmented bran was rich in cyanidin-3-glucoside (58-95%). Ferulic acid was the dominant phenolic acid in the rice bran samples. Black rice bran contained gallic, hydroxybenzoic, and protocatechuic acids in higher contents than red rice bran and normal rice bran. Furthermore, the addition of 5% black rice bran to wheat flour used for making bread produced a marked increase in the free radical scavenging and antioxidant activity compared to a control bread.  相似文献   

16.
In this study, the contents of total phenolics, flavonoids, anthocyanins, β-carotene, and lutein as well as free, conjugated, and insoluble bound phenolic acids were determined in whole kernels of 10 different colored maize genotypes. In addition, the antioxidant activity was evaluated as radical scavenging activity with ABTS (2,2-azino-bis/3-ethil-benothiazoline-6-sulfonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) reagents. Generally, considerable differences in phytochemical contents and antioxidant capacity were observed between the genotypes. The β-carotene and lutein contents ranged from 0 to 2.42 mg/kg d.m. and from 0 to 13.89 mg/kg d.m., respectively, whereas the total anthocyanin contents of anthocyanin-rich colored maize genotypes ranged from 2.50 to 696.07 mg CGE/kg d.m. (cyanidin 3-glucoside equivalent) with cyanidin 3-glucoside (Cy-3-Glu) as the most dominant form. The light blue ZPP-2 selfed maize genotype has a higher content of total phenolics, flavonoids, and ferulic acid as compared to other tested maize and the highest ABTS radical scavenging activity.  相似文献   

17.
The influence of four day/night growing temperature combinations (18/12, 25/12, 25/22, and 30/22 degrees C) on phenolic acid, flavonol, and anthocyanin content and their antioxidant activities against peroxyl radicals (ROO(*)), superoxide radicals (O(2)(*)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radicals (OH(*)), and singlet oxygen ((1)O(2)) in fruit juice of Earliglow and Kent strawberry (Fragaria x ananassa Duch.) cultivars was studied. Pelargonidin-based anthocyanins such as pelargonidin 3-glucoside (291.3-945.1 microg/g fresh wt.), pelargonidin 3-rutinoside (24.7-50.9 microg/g fresh wt.), and pelargonidin 3-glucoside-succinate (62.2-244.0 microg/g fresh wt.) were the predominant anthocyanins in strawberry fruit juice. The content of cyanidin-based anthocyanins, cyanidin 3-glucoside and cyanidin 3-glucoside-succinate, was much lower than that of pelargonidin-based anthocyanins. Strawberry growth in high temperature conditions significantly enhanced the content of p-coumaroylglucose, dihydroflavonol, quercetin 3-glucoside, quercetin 3-glucuronide, kaempferol 3-glucoside, kaempferol 3-glucuronide, cyanidin 3-glucoside, pelargonidin 3-glucoside, pelargonidin 3-rutinoside, cyanidin 3-glucoside-succinate, and pelargonidin 3-glucoside-succinate in strawberry juice. Plants grown in the cool day and cool night temperature (18/12 degrees C) generally had the lowest phenolic acid, flavonols, and anthocyanins. An increase in night temperature from 12 to 22 degrees C, with the day temperature kept constant at 25 degrees C, resulted in a significant increase in phenolic acid, flavonols, and anthocyanins. These conditions also resulted in a significant increase in antioxidant capacity. The highest day/night temperature (30/22 degrees C) yielded fruit with the most phenolic content as well as ROO(*), O(2)(*)(-), H(2)O(2), OH(*), and (1)O(2) radical absorbance capacity. Fruit of Kent cv. strawberry had higher values of phenolic acid, flavonols, anthocyanins, and antioxidant capacities than fruit of Earliglow cv. strawberry under all temperature regimes.  相似文献   

18.
Consumption of berries from various sources including the genus Ribes has been associated with diverse potential health benefits. The 14 examined cultivars of European gooseberry (R. grossularia L.) contained in various proportions the 3-glucoside (3), 3-rutinoside (4), 3-xyloside (7), 3-O-beta-(6' '-E-caffeoylglucopyranoside) (8), and 3-O-beta-(6' '-E-p-coumaroylglucopyranoside) (10) of cyanidin and the 3-rutinoside (6) and 3-glucoside of peonidin (5). Pigments 3, 4, delphinidin 3-rutinoside (2), delphinidin 3-glucoside (1), and minor amounts of 6, 7, and 10 were found in red flowering currant (R. sanguineum Pursh). Golden currant (R. aureum Pursh) contained 3, 4, and trace amounts of 1, 6, and 7, while alpine currant (R. alpinum L.) contained 3, 4, and trace amounts of 10. The major anthocyanins in two cultivars of jostaberries (R. x nidigrolaria Bauer), 1-4, 8, and 10, reflected that this hybrid contained the major anthocyanins of both parents, black currant and gooseberry. This is the first complete identification of 8 and the ring size of the sugar of 10. Pigment 9 was tentatively identified as cyanidin 3-(6' '-Z-p-coumaroylglucoside). This new pigment occurred in minor amounts (<2%) in all R. grosssularia and R. x nidigrolaria cultivars. No commercially available berries have been reported to contain such high proportions of aromatic acylated anthocyanins as found in the gooseberry cultivars "Sams?", "Hinnom?ki Red", "Taastrup", "Lofthus", and "Glendal", which are in this context the most obvious candidates for consumption, colorant, and breeding programs.  相似文献   

19.
Polyphenols present in red table grape varieties Red Globe, Flame Seedless, Crimson Seedless, and Napoleon, and the white varieties Superior Seedless, Dominga, and Moscatel Italica were analyzed by HPLC-DAD-MS. The anthocyanins peonidin 3-glucoside, cyanidin 3-glucoside (and their corresponding p-coumaroyl derivatives), malvidin 3-glucoside, petunidin 3-glucoside, and delphinidin 3-glucoside were found. In addition, caffeoyltartaric acid, p-coumaroyltartaric acid, and the flavonols quercetin 3-glucuronide, quercetin 3-rutinoside, quercetin 3-glucoside, kaempferol 3-galactoside, kaempferol 3-glucoside, and isorhamnetin 3-glucoside were detected. Flavan-3-ols were also detected, and were identified as gallocatechin, procyanidin B1, procyanidin B2, procyanidin B4, procyanidin C1, catechin, and epigallocatechin. These phenolics were present only in the skin, as the flesh of these grape cultivars was almost devoid of these compounds. Anthocyanins were the main phenolics in red grapes ranging from 69 (Crimson Seedless) to 151 (Flame Seedless) mg/kg fresh weight of grapes, whereas flavan-3-ols were the most abundant phenolics in the white varieties ranging from 52 (Dominga) to 81 (Moscatel Italica) mg/kg fresh weight of grapes. Total phenolics ranged from 115 (Dominga) to 361 (Flame Seedless) mg/kg fresh weight of grapes. This means that a serving of unpeeled table grapes (200 g) could provide up to 72 mg of total phenolics (Flame Seedless). These results indicate that the intake of unpeeled table grapes should be recommended in dietary habits as a potential source of antioxidant and anticarcinogenic phenolic compounds.  相似文献   

20.
It has long been considered that the pigments resulting from direct condensation between anthocyanins and flavanols were formed exclusively during storage and processing, both in plant-derived foods and in drinks. Recently, however, the minor presence of this type of pigment has been shown in different plant extracts, among them beans. In this work we have studied this family of pigments in beans from Guatemala belonging to two distinct species of the genus Phaseolus, confirming the presence of (epi)gallocatechin carbon-carbon linked to the aglycone of delphinidin and (epi)catechin-cyanidin-3-glucoside. Furthermore, for the first time in this foodstuff another three flavanol-anthocyanin condensed pigments formed by the linkage of (epi)catechin with the corresponding aglycones of cyanidin, petunidin, and peonidin have been described. Also, the natural occurrence of anthocyanidins in this matrix has been confirmed in some of the samples analyzed in this work, the majority being components of their anthocyanin composition. The corresponding aglycones of delphinidin, cyanidin, petunidin, pelargonidin, and malvidin have been identified as well as two aglycones with identical mass to those of peonidin and petunidin, but with different retention times, which leads to the supposition that they are probably methylated derivatives of cyanidin and delphinidin, respectively.  相似文献   

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