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1.
Cornus mas, Cornus officinalis, Cornus controversa, and Cornus kousa (Cornaceae) bear edible fruits that are consumed in parts of Europe and Asia. This study undertook the investigation of the presence and levels of anthocyanins in the fruits of these Cornus species by HPLC. The anthocyanins present in Cornelian cherries, C. mas, are delphinidin 3-O-beta-galactopyranoside (1), cyanidin 3-O-beta-galactopyranoside (2), and pelargonidin 3-O-beta-galactopyranoside (3). C. officinalis contains only anthocyanins 1-3, similar to C. mas, but in different proportions. However, C. controversa contains anthocyanins 1-3 among other anthocyanins, but Chinese dogwood, C. kousa, did not contain 1-3. The contents of pure anthocyanins 1, 2, and 3 in 1 kg of fresh fruits of C. mas, C. officinalis, and C. controversa were 280, 1079, and 710 ppm; 11, 77, and 230 ppm; and 600, 1000, and 700 ppm, respectively. In cyclooxygenase (COX)-I and -II enzyme inhibitory assays, anthocyanins 1-3 (all 40 microM) showed activities of 9.2 and 11.7%; 7.6 and 12.4%; and 5.3 and 7.8%, respectively, compared to Naproxen (54.3 and 41.3%; 10 microM), ibuprofen (47.5 and 39.8%; 10 microM), Celebrex (46.2 and 66.3%; 1.67 ppm), and Vioxx (23.8 and 88.1%, 1.67 ppm). In the antioxidant assay, anthocyanins 1-3 (all 40 microM) showed activities of 70.2, 60.1, and 40.3%, respectively. At 10 microM concentration, commercial synthetic antioxidants tert-butylhydroquinone, butylated hydroxytoluene, butylated hydroxyanisole, and vitamin E gave 83.2, 79.7, 82.1, and 10.2% of antioxidant activity, respectively.  相似文献   

2.
Antioxidant polyphenols from tart cherries (Prunus cerasus).   总被引:2,自引:0,他引:2  
Montmorency and Balaton tart cherries were lyophilized and sequentially extracted with hexane, ethyl acetate, and methanol. Methanolic extracts of dried Balaton and Montmorency tart cherries (Prunus cerasus) inhibited lipid peroxidation induced by Fe(2+) at 25 ppm concentrations. Further partitioning of this methanol extract with EtOAc yielded a fraction that inhibited lipid peroxidation by 76% at 25 ppm. Purification of this EtOAc fraction afforded eight polyphenolic compounds, 5,7,4'-trihydroxyflavanone (1), 5,7, 4'-trihydroxyisoflavone (2), chlorogenic acid (3), 5,7,3', 4'-tetrahydroxyflavonol-3-rhamnoside (4), 5,7,4'-trihydroxyflavonol 3-rutinoside (5), 5,7,4'-trihydroxy-3'methoxyflavonol-3-rutinoside (6), 5,7,4'-trihydroxyisoflavone-7-glucoside (7), and 6, 7-dimethoxy-5,8,4'-trihydroxyflavone (8), as characterized by (1)H and (13)C NMR experiments. The antioxidant assays revealed that 7-dimethoxy-5,8,4'-trihydroxyflavone (8) is the most active, followed by quercetin 3-rhamnoside, genistein, chlorogenic acid, naringenin, and genistin, at 10 microM concentrations.  相似文献   

3.
The identification of phenolics from various cultivars of fresh sweet and sour cherries and their protective effects on neuronal cells were comparatively evaluated in this study. Phenolics in cherries of four sweet and four sour cultivars were extracted and analyzed for total phenolics, total anthocyanins, and their antineurodegenerative activities. Total phenolics in sweet and sour cherries per 100 g ranged from 92.1 to 146.8 and from 146.1 to 312.4 mg gallic acid equivalents, respectively. Total anthocyanins of sweet and sour cherries ranged from 30.2 to 76.6 and from 49.1 to 109.2 mg cyanidin 3-glucoside equivalents, respectively. High-performance liquid chromatography (HPLC) analysis revealed that anthocyanins such as cyanidin and peonidin derivatives were prevalent phenolics. Hydroxycinnamic acids consisted of neochlorogenic acid, chlorogenic acid, and p-coumaric acid derivatives. Glycosides of quercetin, kaempferol, and isorhamnetin were also found. Generally, sour cherries had higher concentrations of total phenolics than sweet cherries, due to a higher concentration of anthocyanins and hydroxycinnamic acids. A positive linear correlation (r2 = 0.985) was revealed between the total anthocyanins measured by summation of individual peaks from HPLC analysis and the total anthocyanins measured by the pH differential method, indicating that there was in a close agreement with two quantifying methods for measuring anthocyanin contents. Cherry phenolics protected neuronal cells (PC 12) from cell-damaging oxidative stress in a dose-dependent manner mainly due to anthocyanins. Overall results showed that cherries are rich in phenolics, especially in anthocyanins, with a strong antineurodegenerative activity and that they can serve as a good source of biofunctional phytochemicals in our diet.  相似文献   

4.
The fruit of Viburnum dilatatum Thunb., called gamazumi, has been shown to prevent oxidative injury in rats given gamazumi crude extract (GCE). Therefore, phenolic compounds in GCE were purified by Sephadex LH-20 column chromatography and preparative high-performance liquid chromatography. Two major anthocyanins were isolated, and their structures were determined by NMR, liquid chromatography/electrospray ionization mass spectrometry/MS and sugar analysis as cyanidin 3-O-(2-O-beta-D-xylopyranosyl)-beta-D-glucopyranoside, namely, cyanidin 3-sambubioside (I) and that of cyanidin 3-O-beta-D-glucopyranoside, namely, kuromanin (II). This is the first identification of these compounds in V. dilatatum fruits, which contain I and II at 141.3 and 4.5 microg/g of fresh fruit, respectively. By the electron spin resonance method, the superoxide anion radical scavenging activities (IC(50)) of I and II were 17.3 and 69.6 microM, and their activities on hydroxyl radicals were 4.3 and 53.2 mM. As a positive control, the activities of ascorbic acid were 74.2 microM on superoxide anion radicals and 3.0 mM on hydroxyl radicals. Our results suggest that these anthocyanins having radical scavenging properties may be key compounds contributing to the antioxidant activity and physiological effects of V. dilatatum fruits.  相似文献   

5.
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   

6.
In the present study, we addressed the question whether cyanidin-3-glucoside (C3G) or complex C3G-rich blackberry extracts affect human topoisomerases with special emphasis on the contribution of the potential degradation products phloroglucinol aldehyde (PGA) and protocatechuic acid (PCA). In HT29 colon carcinoma cells a C3G-rich blackberry extract suppressed camptothecin- (CPT-) or doxorubicin- (DOX-) induced stabilization of the covalent DNA-topoisomerase intermediate, thus antagonizing the effects of these classical topoisomerase poisons on DNA integrity. As a single compound, C3G (100 μM) decreased the DNA-damaging effects of CPT as well, but did not significantly affect those induced by DOX. At the highest applied concentration (100 μM), cyanidin protected DNA from CPT- and DOX-induced damage. Earlier reports on DNA-damaging properties of cyanidin were found to result most likely from the formation of hydrogen peroxide as an artifact in the cell culture medium when the incubation was performed in the absence of catalase. The suppression of hydrogen peroxide accumulation, achieved by the addition of catalase, demonstrated that cyanidin does not exhibit DNA-damaging properties in HT29 cells (up to 100 μM). The observed effects on topoisomerase interference and DNA protection against CPT or DOX were clearly limited to the parent compound and were not observed for the potential cyanidin degradation products PGA and PCA.  相似文献   

7.
Cultural system [hill plasticulture (HC) versus matted row (MR)] and genotype interactions affected strawberry fruit quality. In general, fruit soluble solids content, total sugar, fructose, glucose, ascorbic acid, titratable acid, and citric acid contents were increased in the HC system. Fruit from HC also had higher flavonoid contents and antioxidant capacities. Strawberry fruit contains flavonols as well as other phenolic compounds such as anthocyanins and phenolic acids. Pelargonidin-based anthocyanins such as pelargonidin 3-glucoside, pelargonidin 3-rutinoside, and pelargonidin 3-glucoside-succinate were the predominant anthocyanins in strawberry fruit. The content of cyanidin-based anthocyanins, cyanidin 3-glucoside and cyanidin 3-glucoside-succinate, was much lower than that of pelargonidin-based anthocyanins in either system. Strawberry fruit from the HC system had significantly higher amounts 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. Fruits from plants grown in the MR system generally had the lowest contents of phenolic acids, flavonols, and anthocyanins. Strawberry fruit grown under HC conditions had significantly higher peroxyl radicals (ROO*) absorbance capacity (ORAC).  相似文献   

8.
An LC-PDA-ESI/MS(n) profiling method was used to identify the anthocyanins of purple Bordeaux radish and led to the assignment of 60 anthocyanins: 14 acylated cyanidin 3-(glucosylacyl)acylsophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5-diglucosides, and 22 acylated cyanidin 3-sophoroside-5-glucosides. The identifications were supported by the presence of 3-sophoroside-5-diglucoside and 3-sophroside-5-glucoside of cyanidin in the alkaline-hydrolyzed extract. A reliable method to identify the anthocyanins containing 3-(glucosylacyl)acylsophorosyl functions is described. The tentative identifications were obtained from tandem mass data analysis and confirmed by high-resolution mass measurements. Further assignments were made for some anthocyanins from a comparison of the mass and UV-vis data and elution order with those of the anthocyanins in the authors' polyphenol database and from consideration of the structural characteristics of the anthocyanins from similar plants and similar anthocyanins in the literature. The presence of 38 acylated cyanidin 3-sophoroside-5-diglucosides and around 10 acylated cyanidin 3-sophoroside-5-malonylglucosides in plants is reported here for the first time.  相似文献   

9.
Antioxidative compounds from the outer scales of onion   总被引:2,自引:0,他引:2  
Antioxidative compounds were isolated from the methanol extract of dry outer scales of onion (Allium cepa L.). Nine phenolic compounds (1-9) were finally obtained by reversed-phase high-performance liquid chromatography, and their structures were elucidated by NMR and mass spectrometry analyses. They were the six known compounds, protocatechuic acid (1), 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2), quercetin 4'-O-beta-D-glucopyranoside (3), quercetin (5), 4'-O-beta-d-glucopyranoside of quercetin dimer (7), and quercetin dimer (8), and three novel compounds, condensation products of quercetin with protocatechuic acid (4), adduct of quercetin with quercetin 4'-O-beta-D-glucopyranoside (6), and quercetin trimer (9). These phenolic compounds were tested for their antioxidant properties using autoxidation of methyl linoleate in bulk phase or free radical initiated peroxidation of soybean phosphatidylcholine in liposomes. The flavonoid compounds having o-dihydroxy substituent in the B-ring were shown to be effective antioxidants against nonenzymic lipid peroxidation.  相似文献   

10.
Arbutus unedo L., the strawberry tree (Ericaceae family), is an evergreen shrub or small tree, typical of the Mediterranean fringe and climate. The aim of the present study was to evaluate the profile of the phenolic constituents of A. unedo fruits. Seven compounds were purified by Sephadex LH-20 column chromatography of the MeOH extract followed by HPLC and were characterized as arbutin, beta-D-glucogalline, gallic acid 4-O-beta-D-glucopyranoside, 3-O-galloylquinic acid, 5-O-galloylquinic acid, 3-O-galloylshikimic acid, and 5-O-galloylshikimic acid, by means of NMR and ESI-MS analyses. Moreover, LC-PDA-MS analysis of the red pigment of A. unedo fruits revealed the presence of three anthocyanins recognized as cyanidin 3-O-beta-D-galactopyranoside, delphinidin 3-O-beta-D-glucopyranoside, and cyanidin 3-O-beta-D-arabinopyranoside. These pigments were also quantified.  相似文献   

11.
In order to further characterize the anthocyanins, flavonols, and other phenolics present in mature saskatoon ( Amelanchier alnifolia Nutt.) fruit, extracts were characterized using high-performance liquid chromatography, gas chromatography, and liquid chromatography-mass spectrometry. Cyanidin 3-O-galactoside, cyanidin 3-O-glucoside, cyanidin 3-O-arabinoside, and cyanidin 3-O-xyloside were identified as the four major anthocyanins in the mature fruit. The quercetin-derived flavonols, quercetin 3-O-glucoside, quercetin 3-O-galactoside, quercetin 3-O-arabinoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoglucoside, quercetin 3-O-robinobioside, and quercetin 3-O-rutinoside were also identified in mature fruit extracts. In addition, two chlorogenic acid isomers (hydroxycinnamates), 3-O-caffeoylquinic acid and 5-O-caffeoylquinic acid were detected. The total content of the anthocyanin-, flavonol-, and hydroxycinnamate-type phenolics detected in mature 'Smoky' saskatoon fruit was 140, 25, and 96 mg/100 g fresh weight, respectively. These data further our knowledge of the phenolic composition of mature saskatoon fruit, and as anthocyanins, flavonols, and hydroxycinnamates exhibit antioxidant activities, the presence and levels of these classes of phenolics will aid in the understanding of the potential health-beneficial effects of saskatoon fruits in the human diet.  相似文献   

12.
Black currant fruits are recognized as being an important dietary source of health-related compounds, such as anthocyanins and ascorbic acid. In the present study, the biochemical composition (viz., nonstructural carbohydrates, individual anthocyanins, total anthocyanins, total phenolics, and organic acids, including ascorbic acid) from 17 UK-grown black currant cultivars was analyzed. Berry composition was significantly affected by genotype. Nonstructural carbohydrates ranged from 85.09 to 179.92 mg g(-1) on a fresh weight (FW) basis, while concentration for organic acids ranged from 36.56 to 73.35 mg g(-1) FW. Relative concentrations of cyanidin 3-glucoside, cyanidin 3-rutinoside, delphinidin 3-glucoside and delphinidin 3-rutinoside were 3.1-7.9%, 35.4-47.0%, 7.6-12.5% and 36.9-50.9%, respectively. Differences in the biochemical profile among cultivars were emphasized by principal component analysis (PCA) and hierarchical cluster analysis (HCA). PCA was able to discriminate between cultivars, especially on the basis of health-related compounds. Initial exploration revealed that individual anthocyanins, total phenolics, and ascorbic acid could be used to characterize and classify different cultivars. HCA showed that the biochemical composition of the different cultivars was related to parentage information.  相似文献   

13.
An UHPLC-PDA-ESI/HRMS/MS(n) profiling method was used for a comprehensive study of the phenolic components of red mustard greens ( Brassica juncea Coss variety) and identified 67 anthocyanins, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned on the basis of direct comparison of the parent flavonoid glycosides with reference compounds. The putative identifications were obtained from tandem mass data analysis and confirmed by the retention time, elution order, and UV-vis and high-resolution mass spectra. Further identifications were made by comparing the UHPLC-PDA-ESI/HRMS/MS(n) data with those of reference compounds in the polyphenol database and in the literature. Twenty-seven acylated cyanidin 3-sophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5-glucosides, 3 acylated cyanidin triglucoside-5-glucosides, 37 flavonol glycosides, and 10 hydroxycinnamic acid derivatives were detected for the first time in brassica vegetables. At least 50 of them are reported for the first time in any plant materials.  相似文献   

14.
The antioxidant activities of a series of commonly consumed and biogenetically related plant phenolics, namely, anthocyanidins, anthocyanins, and catechins, in a liposomal model system have been investigated. The antioxidant efficacies of the compounds were evaluated on their abilities to inhibit the fluorescence intensity decay of an extrinsic probe, 3-[p-(6-phenyl)-1,3,5-hexatrienyl]phenylpropionic acid, caused by free radicals generated during metal ion-induced peroxidation. Distinct structure-activity relationships were revealed for the antioxidant abilities of these structurally related compounds. Whereas antioxidant activity increased with an increasing number of hydroxyl substituents present on the B-ring for anthocyanidins, the converse was observed for catechins. However, substitution by methoxyl groups diminished the antioxidant activity of the anthocyanidins. Substitution at position 3 of ring C played a major role in determining the antioxidant activity of these classes of compounds. The anthocyanidins, which possess a hydroxyl group at position 3, demonstrated potent antioxidant activities. For the cyanidins, an increasing number of glycosyl units at position 3 resulted in decreased antioxidant activity. Similarly, the substitution of a galloyl group at position 3 of the flavonoid moiety resulted in significantly decreased antioxidant activity for the catechins. Among catechins, cis-trans isomerism, epimerization, and racemization did not play a role in overall antioxidant activity. The antioxidant activities of test compounds (at 40 microM concentrations) were compared to the commercial antioxidants tert-butylhydroquinone, butylated hydroxytoluene, butylated hydroxyanisole, and vitamin E (all at 10 microM concentrations).  相似文献   

15.
Four diacylated pelargonidin (Pg: SOA-4 and SOA-6), cyanidin (Cy: YGM-3), and peonidin (Pn: YGM-6) 3-sophoroside-5-glucosides isolated from the red flowers of the morning glory, Pharbitis nil cv. Scarlett O'Hara (SOA), and the storage roots of purple sweet potato, Ipomoea batatas cv. Ayamurasaki (YGM), were subjected to an alpha-glucosidase (AGH) inhibitory assay, in which the assay was performed with the immobilized AGH (iAGH) system to mimic the membrane-bound AGH at the small intestine. As a result, the acylated anthocyanins showed strong maltase inhibitory activities with IC(50) values of <200 microM, whereas no sucrase inhibition was observed. Of these, SOA-4 [Pg 3-O-(2-O-(6-O-(E-3-O-(beta-D-glucopyranosyl)caffeyl)-beta-D-glucopyranosyl)-6-O-E-caffeyl-beta-D-glucopyranoside)-5-O-beta-D-glucopyranoside] possessed the most potent maltase inhibitory activity (IC(50) = 60 microM). As a result of a marked reduction of iAGH inhibitory activity by deacylating the anthocyanins, that is, Pg (or Cy or Pn) sophoroside-5-glucoside, acylation of anthocyanin with caffeic (Caf) or ferulic (Fer) acid was found to be important in the expression of iAGH (maltase) inhibition. In addition, the result that Pg-based anthocyanins showed the most potent maltase inhibition, with an IC(50) value of 4.6 mM, and the effect being in the descending order of potency of Pg > Pn/Cy strongly suggested that no replacement at the 3'(5')-position of the aglycon B-ring may be essential for inhibiting iAGH action.  相似文献   

16.
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   

17.
Mashua (Tropaeolum tuberosum Ruíz and Pavón), an Andean tuber with high antioxidant activity, has sparked interest because of its traditional medicinal use. In this study, we evaluated the anthocyanin composition for three purple mashua genotypes and their contribution to the overall antioxidant activity of the tuber. Mashua anthocyanins, total phenolics, and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) antioxidant activity ranged from 45.5 to 131.9 mg of cyanidin 3-glucoside equivalents/100 g fresh weight (FW), 174.9 to 275.5 mg of gallic acid equivalents/100 g of FW, and 16.2 to 45.7 micromol of Trolox equivalents/g of FW, respectively. The high-performance liquid chromatography with photodiode array detection (HPLC-DAD) and HPLC-electrospray ionization tandem mass spectrometry (ESI/MS-MS) profiles revealed the presence of 11 different anthocyanins. The two major pigments (56.4-73.0% total area range at 520 nm) were identified as delphinidin 3-glucoside-5-acetylrhamnoside and delphinidin 3-sophoroside-5-acetylrhamnoside. Other pigments were delphinidin 3-glucoside-5-rhamnoside, delphinidin 3-sophoroside-5-rhamnoside, delphinidin 3-glucoside, cyanidin 3-sophoroside, and cyanidin 3-sophoroside-5-rhamnoside. Cyanidin 3-glucoside and cyanidin 3-rutinoside were only found in two genotypes, while pelargonidin 3-sophoroside and pelargonidin 3-sophoroside-5-rhamnoside were only found in the third one. Anthocyanins from mashua were the major contributors to the total ABTS values for only one of the three genotypes, suggesting that other phenolics present are playing a major role in the antioxidant power of mashua tubers. Results from this study provide important information for the Nutraceutical and Functional Food Market for the use of mashua anthocyanins not only as a source of natural colorants but also as a source of phytonutrients.  相似文献   

18.
Polyphenols, chlorophylls, and carotenoids were characterized by HPLC-DAD-MS(n) in the pericarp of unripe to over-ripe 'Hong Huey' and 'Chacapat' litchi fruit at harvest and during subsequent storage (5 °C, 90% RH, 21 days). (-)-Epicatechin and A-type procyanidins always predominated quantitatively. Besides these ortho-diphenolic compounds, minor novel litchi flavonoids included monohydroxylated structures. Chlorophyll degradation by 73-92% and 7-38-fold anthocyanin accumulation affected pericarp color throughout the last 15-20 days of on-tree maturation. Postharvest, anthocyanins and (-)-epicatechin largely degraded within the first 3 days, accompanied by severe pericarp browning. Without packaging of the fruit, desiccation initially accelerated polyphenol oxidase-induced oxidation of (-)-epicatechin, but then hindered its further progress. Constant levels of the monohydroxylated (epi)afzelechin indicated no involvement of peroxidase. Acting as antioxidants, anthocyanins retarded (-)-epicatechin degradation. Hence, pinkish-red fruit with a molar ratio of cyanidin 3-O-rutinoside to (-)-epicatechin of >3:100 retained flavonoids best. However, brown polymers masked remaining red pigments.  相似文献   

19.
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   

20.
A method has been established and validated for identification and quantification of individual, as well as total, anthocyanins by HPLC and LC/ES-MS in botanical raw materials used in the herbal supplement industry. The anthocyanins were separated and identified on the basis of their respective M(+) (cation) using LC/ES-MS. Separated anthocyanins were individually calculated against one commercially available anthocyanin external standard (cyanidin-3-glucoside chloride) and expressed as its equivalents. Amounts of each anthocyanin calculated as external standard equivalent were then multiplied by a molecular-weight correction factor to afford their specific quantities. Experimental procedures and use of a molecular-weight correction factors are substantiated and validated using Balaton tart cherry and elderberry as templates. Cyanidin-3-glucoside chloride has been widely used in the botanical industry to calculate total anthocyanins. In our studies on tart cherry and elderberry, its use as external standard followed by use of molecular-weight correction factors should provide relatively accurate results for total anthocyanins, because of the presence of cyanidin as their major anthocyanidin backbone. The method proposed here is simple and has a direct sample preparation procedure without any solid-phase extraction. It enables selection and use of commercially available anthocyanins as external standards for quantification of specific anthocyanins in the sample matrix irrespective of their commercial availability as analytical standards. It can be used as a template and applied for similar quantification in several anthocyanin-containing raw materials for routine quality control procedures, thus providing consistency in analytical testing of botanical raw materials used for manufacturing efficacious and true-to-the-label nutritional supplements.  相似文献   

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