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1.
The HPLC retention time, photodiode array UV spectrum analysis, and LC/MS results indicated that arbutin and chlorogenic acid are the main phenolic constituents in Oriental pear. The two compounds exist in different organs of the Yali pear, which is one of the major cultivars of Pyrus bretschnrideri. The contents of arbutin in the leaf bud, floral bud, flower, and young fruit were 11.9, 12.4, 8.29, and 9.92 mg/g fresh weight (FW), respectively. Chlorogenic acid amounts in the same organs were 2.26, 3.22, 5.32, and 3.72 mg/g FW, respectively. During development, the concentration of the two compounds in Yali pears was the greatest in young fruit (9.92 mg/g FW of arbutin and 3.72 mg/g FW of chlorogenic acid), and then declined swiftly with fruit growth to less than 0.400 and 0.226 mg/g FW, respectively, in mature fruit. Large differences existed in the distribution of the two compounds in parts of the mature fruit of 14 Oriental pear cultivars. The greatest concentration of arbutin was found in the peel (1.20 mg/g FW), which was 3-5 times greater than that found in the core and 10-45 times greater than the level in the pulp. The concentration of chlorogenic acid in the core was greater than that in the peel. The compounds in 17 cultivars of Oriental pear, including P. bretschnrideri, Pyrus pyrifolia, Pyrus ussuriensis, and Pyrus sinkiangensis, were compared with those in 5 cultivars of Occidental pear (Pyrus communis). The mean concentration of arbutin in the Oriental pear cultivars was 0.164 mg/g FW, greater than the 0.083 mg/g FW found in the Occidental pear cultivars. The greatest arbutin content was 0.400 mg/g FW, found in the Yali pear. However, the mean concentration of chlorogenic acid in the Oriental pear was 0.163 mg/g FW, less than that found in the Occidental pear (0.309 mg/g FW).  相似文献   

2.
The contribution of each phytochemical to the total antioxidant capacity of apples was determined. Major phenolic phytochemicals of six apple cultivars were identified and quantified, and their contributions to total antioxidant activity of apples were determined using a 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assay and expressed as vitamin C equivalent antioxidant capacity (VCEAC). Average concentrations of major phenolics and vitamin C in six apple cultivars were as follows (mg/100 g of fresh weight of apples): quercetin glycosides, 13.20; procyanidin B(2), 9.35; chlorogenic acid, 9.02; epicatechin, 8.65; phloretin glycosides, 5.59; vitamin C, 12.80. A highly linear relationship (r (2) > 0.97) was attained between concentrations and total antioxidant capacity of phenolics and vitamin C. Relative VCEAC values of these compounds were in the order quercetin (3.06) > epicatechin (2.67) > procyanidin B(2) (2.36) > phloretin (1.63) > vitamin C (1.00) > chlorogenic acid (0.97). Therefore, the estimated contribution of major phenolics and vitamin C to the total antioxidant capacity of 100 g of fresh apples is as follows: quercetin (40.39 VCEAC) > epicatechin (23.10) > procyanidin B(2) (22.07) > vitamin C (12.80) > phloretin (9.11) > chlorogenic acid (8.75). These results indicate that flavonoids such as quercetin, epicatechin, and procyanidin B(2) rather than vitamin C contribute significantly to the total antioxidant activity of apples.  相似文献   

3.
Fruit physical and chemical characters of 29 apricot cultivars of Greek and American origin and their hybrids were evaluated using correlation and principal component analysis. A remarkable variation was observed in the total phenol content (0.3-7.4 mg gallic acid equivalent g(-1) FW) and total antioxidant capacity (0.026-1.858 mg ascorbic acid equivalent g(-1) FW), with the American origin cultivars Robada and NJA(2) and the new cultivar Nike exhibiting the greatest values. The cultivar Tomcot and hybrid 467/99 had the highest content of total carotene (37.8 microg beta-carotene equivalent g(-1) FW), which was up to four times greater as compared with the rest of studied genotypes. The dominant sugar in fruit tissue was sucrose, followed second by glucose and third by sorbitol and fructose-inositol. The new cultivars Nike, Niobe, and Neraida contained relatively higher contents of sucrose and total sugars, while Ninfa and P. Tirynthos contained relatively higher contents of K, Ca, and Mg. Correlation analysis suggested that late-harvesting cultivars/hybrids had greater fruit developmental times (r = 0.817) and contained higher sugar (r = 0.704) and less Mg contents (r= -0.742) in fruit tissue. The total antioxidant capacity was better correlated with the total phenol content (r = 0.954) as compared with the total carotenoid content (r = 0.482). Weak correlations were found between the fruit skin color and the antioxidant contents in flesh tissue. Multivariate analysis allowed the grouping of variables, with more important variables being the harvest date, fruit developmental time, skin Chroma, sorbitol, and total sugar, K and Mg contents. Plotting the genotypes in a dendrogram revealed cases of homonymy between parents and hybrids, although independent segregation of the measured traits after hybridization was also found.  相似文献   

4.
The antioxidant activities of eight apple cultivars were studied by using the ferric reducing/antioxidant power (FRAP), the beta-carotene-linoleic acid model system (beta-CLAMS), and the photochemiluminescent (PCL) assays. The antioxidant activity of apples is highly correlated to the total phenolic content (TPC) measured by the Folin-Ciocalteu method and the total polyphenolic index (TPI) obtained by HPLC. Extracts of the peel and flesh were analyzed and assayed separately. The FRAP activities of both peel and flesh extracts correlate well with the TPC (r = 0.95 and 0.99, respectively) and the TPI (r = 0.82 and 0.99, respectively). Similar results were found in the beta-CLAMS activities, showing correlation coefficients of r = 0.90 and 0.91 with the TPC for the peel and flesh extracts and of r = 0.90 and 0.84 with the TPI for the peel and flesh extracts, respectively. The antioxidant activity measured by the PCL assay was not correlated with TPC or TPI due to the lack of integratable lag phase in this method with the flavan-3-ols/procyanidins. Among the five major polyphenolic groups, flavan-3-ols/procyanidins had the highest positive correlation with the FRAP and beta-CLAMS activities: r = 0.84 and 0.88 for the peel extracts, respectively; and r = 0.98 and 0.87 for the flesh extracts, respectively. At individual compound level, epicatechin and procyanidin B2 were the major contributors to the antioxidant activity of apple. Hydroxycinnamic acids may have a significant role in the flesh.  相似文献   

5.
Thirty-seven apricot varieties, including four new releases (Rojo Pasión, Murciana, Selene, and Dorada) obtained from different crosses between apricot varieties and three traditional Spanish cultivars (Currot, Mauricio, and Búlida), were separated according to flesh color into four groups: white, yellow, light orange, and orange (mean hue angles in flesh were 88.1, 85.0, 77.6, and 72.4, respectively). Four phenolic compound groups, procyanidins, hydroxycinnamic acid derivatives, flavonols, and anthocyanins, were identified by HPLC-MS/MS and individually quantified using HPLC-DAD. Chlorogenic and neochlorogenic acids, procyanidins B1, B2, and B4, and some procyanidin trimers, quercetin 3-rutinoside, kaempferol 3-rhamnosyl-hexoside and quercetin 3-acetyl-hexoside, cyanidin 3-rutinoside, and 3-glucoside, were detected and quantified in the skin and flesh of the different cultivars. The total phenolics content, quantified as the addition of the individual compounds quantified by HPLC, ranged between 32.6 and 160.0 mg 100 g(-1) of edible tissue. No correlation between the flesh color and the phenolic content of the different cultivars was observed.  相似文献   

6.
To study the effect of polyphenolics on antioxidant capacities of plums, the amounts of total phenolics, total flavonoids and individual phenolic compounds, and vitamin C equivalent antioxidant capacity (VCEAC) of eleven plum cultivars was determined. There was a good linear relationship between the amount of total phenolics and total antioxidant capacity (r2 = 0.9887). The amount of total flavonoids and total antioxidant capacity also showed a good correlation (r2 = 0.9653). Although the summation of individual antioxidant capacity was lower than the total antioxidant capacity of plum samples, there was a positive correlation (r2 = 0.9299) of total antioxidant capacity of plum samples with the sum of the VCEACs calculated from individual phenolics. Chlorogenic acids and glycosides of cyanidin, peonidin, and quercetin were major phenolics among eleven plum cultivars. The antioxidant capacity of chlorogenic acids and anthocyanins showed higher correlation (r2) of 0.7751 and 0.6616 to total VCEAC, respectively, than that of quercetin glycosides (r2 = 0.0279). Chlorogenic acids were a major source of antioxidant activity in plums, and the consumption of one serving (100 g) of plums can provide antioxidants equivalent to 144.4-889.6 mg of vitamin C.  相似文献   

7.
The polyphenolic composition of natural ciders from the Asturian community (Spain), during 2 consecutive years, was analyzed by RP-HPLC and the photodiode-array detection system, without previous extraction (direct injection). A total of 16 phenolic compounds (catechol, tyrosol, protocatechuic acid, hydrocaffeic acid, chlorogenic acid, hydrocoumaric acid, ferulic acid, (-)-epicatechin, (+)-catechin, procyanidins B2 and B5, phloretin-2'-xyloglucoside, phloridzin, hyperin, avicularin, and quercitrin) were identified and quantified. A fourth quercetin derivative, one dihydrochalcone-related compound, two unknown procyanidins, three hydroxycinnamic derivatives, and two unknown compounds were also found. Among the low-molecular-mass polyphenols analyzed, hydrocaffeic acid was the most abundant compound, representing more than 80% of the total polyphenolic acids. Procyanidins were the most important family among the flavonoid compounds. Discriminant analysis was allowed to correctly classify more than 93% of the ciders, according to the harvest year; the most discriminant variables were an unknown procyanidin and quercitrin.  相似文献   

8.
Procyanidins can bind cell wall material in raw product, and it could be supposed that the same mechanism of retention of procyanidins by apple cell walls takes place in cooked products. To evaluate the influence of cell wall composition and disassembly during cooking on the cell walls' capacity to interact with procyanidins, four cell wall materials differing in their protein contents and physical characteristics were prepared: cell wall with proteins, cell wall devoid of protein, and two processed cell walls differing by their drying method. Protein contents varied from 23 to 99 mg/g and surface areas from 1.26 to 3.16 m(2)/g. Apple procyanidins with an average polymerization degree of 8.7 were used. The adsorption of apple procyanidins on solid cell wall material was quantified using the Langmuir isotherm formulation. The protein contents in cell wall material had no effect on procyanidin/cell wall interactions, whereas modification of the cell wall material by boiling, which reduces pectin content, and drying decreased the apparent affinity and increased the apparent saturation levels when constants were expressed relative to cell wall weight. However, boiling and drying increased apparent saturation levels and had no effect on apparent affinity when the same data were expressed per surface units. Isothermal titration calorimetry indicated strong affinity (K(a) = 1.4 × 10(4) M(-1)) between pectins solubilized by boiling and procyanidins. This study higllights the impact of highly methylated pectins and drying, that is, composition and structure of cell wall in the cell wall/procyanidin interactions.  相似文献   

9.
The phenolic compounds of 25 peach, nectarine, and plum cultivars were studied and quantified by HPLC-DAD-ESIMS. Hydroxycinnamates, procyanidins, flavonols, and anthocyanins were detected and quantified. White and yellow flesh nectarines and peaches, and yellow and red plums, were analyzed at two different maturity stages with consideration of both peel and flesh tissues. HPLC-MS analyses allowed the identification of procyanidin dimers of the B- and A-types, as well as the presence of procyanidin trimers in plums. As a general rule, the peel tissues contained higher amounts of phenolics, and anthocyanins and flavonols were almost exclusively located in this tissue. No clear differences in the phenolic content of nectarines and peaches were detected or between white flesh and yellow flesh cultivars. There was no clear trend in phenolic content with ripening of the different cultivars. Some cultivars, however, had a very high phenolic content. For example, the white flesh nectarine cultivar Brite Pearl (350-460 mg/kg hydroxycinnamates and 430-550 mg/kg procyanidins in flesh) and the yellow flesh cv. Red Jim (180-190 mg/kg hydroxycinnamates and 210-330 mg/kg procyanidins in flesh), contained 10 times more phenolics than cultivars such as Fire Pearl (38-50 mg/kg hydroxycinnamates and 23-30 mg/kg procyanidins in flesh). Among white flesh peaches, cultivars Snow King (300-320 mg/kg hydroxycinnamates and 660-695 mg/kg procyanidins in flesh) and Snow Giant (125-130 mg/kg hydroxycinnamates and 520-540 mg/kg procyanidins in flesh) showed the highest content. The plum cultivars Black Beaut and Angeleno were especially rich in phenolics.  相似文献   

10.
Antioxidants such as vitamin C, vitamin E, and carotenoids have been reported to prevent the progression of experimentally induced cataracts. However, little is known of the effect of procyanidins, a powerful antioxidant, on cataract formation. This paper investigates the anticataract activity of grape seed extract (GSE, which contains 38.5% procyanidins) in hereditary cataractous rats (ICR/f rats). The ICR/f rats were fed a standard diet containing 0 or 0.213% GSE [0.082% procyanidins in the diet (w/w)] for 27 days. The GSE significantly prevented and postponed development of cataract formation by evaluation of slit lamp observations of the rats' eyes. Lens weight and malondialdehyde concentration in the lens and plasma cholesteryl ester hydroperoxide (ChE-OOH) level induced by CuSO4 were significantly lower in the GSE group compared with the control group. The rats were also fed for 14 days either the diet containing 0.085% procyanidin dimer to tetramer fraction (0.085% as the procyanidins), the diet containing 0.090% procyanidin pentamer to heptamer fraction (0.085% as the procyanidins), or the diet containing 0.093% procyanidin oligomers more than decamer fraction (0.085% as the procyanidins). The ChE-OOH levels in the procyanidin pentamer to heptamer and procyanidin oligomers more than decamer groups were significantly lower than in the procyanidin dimer to tetramer group. These results suggested that procyanidins and their antioxidative metabolites prevented the progression of cataract formation by their antioxidative action. The larger molecular procyanidins in the GSE might contribute this anticataract activity.  相似文献   

11.
The rate of consumption of dissolved oxygen by apple polyphenol oxidase in cider apple juices did not correlate with polyphenol oxidase activity in the fruits and decreased faster than could be explained by the decrease of its polyphenolic substrates. The kinetics parameters of a crude polyphenol oxidase extract, prepared from apple (Braeburn cultivar), were determined using caffeoylquinic acid as a substrate. Three apple procyanidin fractions of n 80, 10.5, and 4 were purified from the parenchyma of cider apples of various cultivars. Procyanidins, caffeoylquinic acid, (-)-epicatechin, and a mixture of caffeoylquinic acid and (-)-epicatechin were oxidized by reaction with caffeoylquinic acid o-quinone in order to form oxidation products. All the fractions were evaluated for their inhibitory effect on PPO activity. Native procyanidins inhibited polyphenol oxidase activity, the inhibition intensity increasing with n. The polyphenol oxidase activity decreased by 50% for 0.026 g/L of the fraction of n 80, 0.17 g/L of the fraction of n 10.5, and 1 g/L of the fraction of n 4. The inhibitory effect of oxidized procyanidins was twice that of native procyanidins. Oxidation products of caffeoylquinic acid and (-)-epicatechin also inhibited polyphenol oxidase.  相似文献   

12.
The contents of chalconaringenin, chlorogenic acid, rutin, ascorbic acid, lycopene, and beta-carotene were analyzed during postharvest and vine ripening of cherry tomatoes (Lycopersicon esculentumMill.) (cv. Jennita) produced in a greenhouse. A remarkable decrease in the content of chalconaringenin took place during postharvest ripening. The tomatoes were found to contain 15.26 mg 100 g(-1) fresh weight (FW) at harvest but held only 0.41 mg after 3 weeks at 20 degrees C in darkness. Chalconaringenin did not convert into naringenin. The content of chlorogenic acid fell from 0.51 to 0.06 mg 100 g(-1) FW at the same conditions. The content of rutin and that of total phenolics remained stable during postharvest ripening. The amounts of lycopene as well as beta-carotene and ascorbic acid increased during postharvest ripening. No significant change in the amount of methanol soluble antioxidants or total soluble solids was found during postharvest ripening of the tomato fruits. During vine ripening, the total amount of phenolics and that of soluble solids (% Brix) increased. The content of phenolics correlated well with the content of methanol soluble antioxidants (p < 0.001). The amount of ascorbic acid increased from 9.7 mg in green-yellow tomatoes to 17.1 mg 100 g(-1) FW in red tomatoes. The amount of chalconaringenin decreased to 8.16 mg 100 g(-1) FW, whereas no significant change was observed for chlorogenic acid or rutin. Possible causes for the decrease in chalconaringenin are discussed.  相似文献   

13.
The relationship between phenolic composition and radical scavenging activity of apple peel and pulp was investigated in fruit produced according to both organic and integrated agricultural methods. Apple tissue extracts were subjected to high-performance liquid chromatography separation, which showed that as compared with pulps, peels are richer in almost all of the quantified phenolics. Flavonols, flavanols, procyanidins, dihydrochalcones, and hydroxycinnamates were the identified phenolic classes in peel tissue, and the most abundant compounds were epicatechin, procyanidin B2, and phloridzin. Pulps were poorer in phytochemicals. Their major phenolics were procyanidins and hydroxycinnamates. Flavonols in amounts <20 mg kg(-1) fresh weight (fw) were also found. In both peels and pulps, integrated production samples were richer in polyphenols. Among the 14 compounds identified, only phloridzin had a tendency to appear higher in organic peels. The total antioxidant capacities (TAC) of extracts were evaluated using the 1,1-diphenyl-2-picrylhydrazyl radical assay and were expressed as Trolox equivalents. Integrated peels gave the highest TAC (18.56 mM kg(-1) fw), followed by organic peels (TAC = 14.96), integrated pulps (TAC = 7.12), and organic pulps (TAC = 6.28). In peels, the top contributors to the antioxidant activity were found to be flavonols, flavanols, and procyanidins, which accounted for about 90% of the total calculated activity whereas in pulps, the TAC was primarily derived from flavanols (monomers and polymers) together with hydroxycinnamates. A good correlation between the sum of polyphenols and the radical scavenging activities was found. Among the single classes of compounds, procyanidins (in peels and pulps) and flavonols (in peels) were statistically correlated to the TAC.  相似文献   

14.
The phenolic constituents of seeds of 12 different apple cultivars were fractionated by sequential extraction with aqueous acetone (30:70, v/v) and ethyl acetate after hexane extraction of the lipids. Low molecular weight phenolic compounds were individually quantitated by RP-HPLC-DAD. The contents of extractable and nonextractable procyanidins were determined by applying RP-HPLC following thiolysis and n-butanol/HCl hydrolysis, respectively. As expected, the results revealed marked differences of the ethyl acetate extracts, aqueous acetone extracts, and insoluble residues with regard to contents and mean degrees of polymerization of procyanidins. Total phenolic contents in the defatted apple seed residues ranged between 18.4 and 99.8 mg/g. Phloridzin was the most abundant phenolic compound, representing 79-92% of monomeric polyphenols. Yields of phenolic compounds significantly differed among the cultivars under study, with seeds of cider apples generally being richer in phloridzin and catechins than seeds of dessert apple cultivars. This is the first study presenting comprehensive data on the contents of phenolic compounds in apple seeds comprising extractable and nonextractable procyanidins. Furthermore, the present work points out a strategy for the sustainable and complete exploitation of apple seeds as valuable agro-industrial byproducts, in particular as a rich source of phloridzin and antioxidant flavanols.  相似文献   

15.
The flavor of eight cocoa liquors of different origins (Africa, America, and Asia) and different varieties (Fine grades: criollo, trinitario, and nacional. Bulk-basic grade: forastero.) was analyzed by headspace solid-phase microextraction mass spectrometry (HS-SPME-MS). Their procyanidin contents were quantified by HPLC-UV (280 nm). Fine varieties with short fermentation processes proved to contain more procyanidins, while criollo from New Guinea and forastero beans showed the highest aroma levels. The levels of cocoa aroma compounds formed during roasting are shown to vary directly with bean fermentation time and inversely with residual procyanidin content in cocoa liquor. Measurement of antioxidant activity in cocoa liquor proved to be a useful tool for assessing residual polyphenols.  相似文献   

16.
The phenolic compounds hydroxycinnamates, anthocyanins, flavonols, and flavan-3-ols of sweet cherry cultivars Burlat, Saco, Summit, and Van harvested in 2001 and 2002 were quantified by HPLC-DAD. Phenolics were analyzed at partially ripe and ripe stages and during storage at 15 +/- 5 degrees C (room temperature) and 1-2 degrees C (cool temperature). Neochlorogenic and p-coumaroylquinic acids were the main hydroxycinnamic acid derivatives, but chlorogenic acid was also identified in all cultivars. The 3-glucoside and 3-rutinoside of cyanidin were the major anthocyanins. Peonidin and pelargonidin 3-rutinosides were the minor anthocyanins, and peonidin 3-glucoside was also present in cvs. Burlat and Van. Epicatechin was the main monomeric flavan-3-ol with catechin present in smaller amounts in all cultivars. The flavonol rutin was also detected. Cultivar Saco contained the highest amounts of phenolics [227 mg/100 g of fresh weight (fw)] and cv. Van the lowest (124 mg/100 g of fw). Phenolic acid contents generally decreased with storage at 1-2 degrees C and increased with storage at 15 +/- 5 degrees C. Anthocyanin levels increased at both storage temperatures. In cv. Van the anthocyanins increased up to 5-fold during storage at 15 +/- 5 degrees C (from 47 to 230 mg/100 g of fw). Flavonol and flavan-3-ol contents remained quite constant. For all cultivars the levels of phenolic acids were higher in 2001 and the anthocyanin levels were higher in 2002, which suggest a significant influence of climatic conditions on these compounds.  相似文献   

17.
In the United States, commercially available foods, including cocoa and chocolate, are being marketed with statements referring to the level of antioxidant activity and polyphenols. For cocoa-containing foods, there has been no comprehensive survey of the content of these and other chemistries. A survey of cocoa and chocolate-containing products marketed in the United States was conducted to determine antioxidant activity and polyphenol and procyanidin contents. Commercially available samples consisted of the top market share products in each of the following six categories: natural cocoa, unsweetened baking chocolate, dark chocolate, semisweet baking chips, milk chocolate, and chocolate syrup. Composite samples were characterized using four different methods: oxygen radical absorbance capacity (ORAC), vitamin C equivalence antioxidant capacity (VCEAC), total polyphenols, and procyanidins. All composite lots were further characterized for percent nonfat cocoa solids (NFCS) and percent fat. Natural cocoas had the highest levels of antioxidant activities, total polyphenols, and procyanidins followed by baking chocolates, dark chocolates and baking chips, and finally milk chocolate and syrups. The results showed a strong linear correlation between NFCS and ORAC (R (2) = 0.9849), total polyphenols (R (2) = 0.9793), and procyanidins (R (2) = 0.946), respectively. On the basis of principal component analysis, 81.4% of the sample set was associated with NFCS, antioxidant activity, total polyphenols, and procyanidins. The results indicated that, regardless of the product category, NFCS were the primary factor contributing to the level of cocoa antioxidants in the products tested. Results further suggested that differences in cocoa bean blends and processing, with the possible exception of Dutching, are minor factors in determining the level of antioxidants in commercially available cocoa-containing products in the United States.  相似文献   

18.
The polyphenol contents and antioxidant activities were assessed for 17 Saskatoon berry cultivars grown in Canada in fresh and stored fruits at -20 degrees C for 9 months. The Nelson cultivar was the richest in total polyphenol, anthocyanin, and procyanidin contents (801, 382, and 278 mg/100 g fresh weight, respectively). This cultivar was characterized also by the highest antioxidant potential measured with DPPH and ABTS radicals (2.8 and 5.0 mM/100 g FW, respectively). Cultivar-dependent changes in polyphenol content after freezer storage were observed. In the Lee 2 cultivar, significant increases in anthocyanin and flavonol contents occurred, while in the Lee 3 and Martin cultivars considerable decreases were observed. During the freezer storage, the antioxidant activity remained unchanged except for the Smokey which showed to be the most sensitive cultivar during storage. The Nelson and Lee 2 were the most stable cultivars during storage. The high polyphenol content and antioxidant activity of the Nelson cultivar and its good storage stability would make this cultivar the optimal material for fruit growers and food producers.  相似文献   

19.
Antioxidant activity and phenolic content of Oregon caneberries   总被引：6，自引：0，他引：6  
Five types of caneberries [evergreen blackberries (Rubus laciniatus), marionberries (Rubus ursinus), boysenberries (Rubus ursinus x idaeus), red raspberries (Rubus idaeus), and black raspberries (Rubus occidentalis)] were analyzed for antioxidant activity by measuring their oxygen radical absorbance capacity (ORAC). In addition, the berries were analyzed for total phenolics, anthocyanins, procyanidins, and ellagic acid content. All of the berries had high ORAC activity ranging from 24 to 77.2 micromol of Trolox equiv/g of fresh berries. Anthocyanin content ranged from 0.65 to 5.89 mg/g, and phenolics ranged from 4.95 to 9.8 mg/g. Black raspberries had the highest ORAC and anthocyanin and phenolic contents. Only red raspberries had detectable amounts of procyanidin oligomers (monomer, dimers, and trimers). All berries had high levels of ellagic acid (47-90 mg/g), but boysenberries had the highest level prior to hydrolysis. The results from this study indicate that these caneberries were high in antioxidant activity and were rich sources of anthocyanins and phenolics.  相似文献   

20.
There is considerable evidence to show that a greater intake of apple contributes to improved health by reducing the risk of diseases, such as cardiovascular disease and some forms of cancer. Apple fruit is a major source of phenol compounds, because its consumption is widespread in many countries and it is available on the market for the whole year. The phenolic composition of 67 varieties of apple cultivars (new and old varieties) was examined for the concentration of some important phytochemicals and antioxidant activity. For the first time, we have looked at the correlation and compared polyphenolic coumpounds in Golden Delicious variety and new varieties grown from it. Up to 18 compounds, including catechin, procyanidin, hydroxycinnamates, flavonols, anthocyanins, and dihydrochalcones, were analyzed by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis and LC-MS. The mean content of total polyphenols lay between 523.02 and 2723.96 mg/100 g dw and depending upon the apples variety. Flavanols (catechin and oligomeric procyanidins) are the major class of apple polyphenols, representing more than 80%, followed by hydroxycinnamic acids (1-31%), flavonols (2-10%), dihydrochalcones (0.5-5%), and in red apples, anthocyanins (1%). In this study, the best correlation was found for the total polyphenols and ABTS method, with a lower correlation for FRAP and DPPH methods ( r = 0.871, 0.839, and 0.804, respectively). The presented data clearly demonstrated that new varieties, i.e., Ozark Gold, Julyred, and Jester, of apple had the same or higher value of bioactive compounds in comparison to the old varieties, i.e., Golden Delicious, Idared, and Jonagold.  相似文献   

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