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Chlorogenic Acid (chlorogenic + acid)
Selected AbstractsPhenolic Acid Content and Composition in Leaves and Roots of Common Commercial Sweetpotato (Ipomea batatas L.) Cultivars in the United StatesJOURNAL OF FOOD SCIENCE, Issue 6 2007V.-D. Truong ABSTRACT:, Phenolic acids in commercially important sweet potato cultivars grown in the United States were analyzed using reversed-phase high-performance liquid chromatography (HPLC). Caffeic acid, chlorogenic acid, 4,5-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 3,4-di-O-caffeoylquinic acid were well separated with an isocratic elution in less than 25 min compared to about 120 min for analyzing and re-equilibrating the column with a gradient method. The isocratic elution order of these caffeoylquinic acid derivatives was confirmed by LC-MS/MS. Chlorogenic acid was the highest in root tissues, while 3,5-di-O-caffeoylquinic acid and/or 4,5-di-O-caffeoylquinic acid were predominant in the leaves. Steam cooking resulted in statistically nonsignificant increases in the concentration of total phenolics and all the individual phenolic acids identified. Sweetpotato leaves had the highest phenolic acid content followed by the peel, whole root, and flesh tissues. However, there was no significant difference in the total phenolic content and antioxidant activity between purees made from the whole and peeled sweet potatoes. [source] Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Mateja Colaric Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source] Recurrent selection for maysin, a compound in maize silks, antibiotic to earwormPLANT BREEDING, Issue 4 2001N. W. Widstrom Abstract A thorough knowledge of the inheritance of maysin, a flavone glycoside with antibiosis to corn earworm, Helicoverpa zea Boddie, in the silks of maize will assist breeders in choosing the most efficient method of incorporating this trait into elite inbreds. Two breeding populations, one having exotic origin (EPM), the other from southern inbred lines (SIM) were subjected to six cycles of recurrent selection for increased silk maysin. Ten per cent of the individuals evaluated in populations were selected for recombination as S1 progenies in each cycle. Progress was evaluated as C0 to C6 population cycles in a randomized complete-block experiment with five replications in 1997 and 1998. Maysin fresh weights in silks of the C0 populations were 0.54% for EPM and 0.36% for SIM. Responses of 0.19% per cycle in EPM and 0.22% per cycle in SIM resulted in an EPM (C6) population with 1.76% maysin and an SIM (C6) population with 1.69% maysin. Silk maysin concentrations above 0.2% begin to substantially reduce larval growth and prevent completion of the life cycle when husk coverage is sufficient to force the insect to feed on silks while entering the ear. Chlorogenic acid and two analogues of maysin, apimaysin and 3,-methoxymaysin, were found in such minor quantities in silks that they could not be credited with any impact on antibiotic activity against the insect. Selection has effectively increased silk maysin concentration in both EPM and SIM. Trait responses for maysin are highly heritable and will allow the plant breeder to introgress resistance to the corn earworm into elite material easily. [source] Phenolic compounds in peach (Prunus persica) cultivars at harvest and during fruit maturationANNALS OF APPLIED BIOLOGY, Issue 1 2008C. Andreotti Abstract Six peach and six nectarine cultivars were evaluated for the phenolic content in their pulp and peel tissues. Chlorogenic acid, catechin, epicatechin, rutin and cyanidin-3-glucoside were detected as the main phenolic compounds of ripened fruits. The concentration was always higher in peel tissue, with average values ranging from 1 to 8 mg g,1 dry weight (DW) depending on cultivar. Of the tested varieties, the white-flesh nectarine ,Silver Rome' emerged as the cultivar with the highest amount of total phenolics. Phenolic compounds were also profiled during fruit growth and ripening in the yellow nectarine cv. ,Stark Red Gold', which showed a decreasing concentration during fruit development in both peel and pulp tissues. Average amounts of total phenolics were approximately 25 mg g,1 DW 60 days after full bloom and decreased to 3 mg g,1 DW at ripening in pulp tissue. Differences among peel and pulp composition show the different dietetic and antioxidant potential of fruits consumed unpeeled and peeled. [source] Physicochemical Characteristics of Green Coffee: Comparison of Graded and Defective BeansJOURNAL OF FOOD SCIENCE, Issue 5 2007K. Ramalakshmi ABSTRACT:, Defective (triage) coffee beans are beans rejected after separating the graded ones according to the size and color. These coffee beans represent about 15% to 20% of coffee production in India but are not utilized for beverages since these affect the quality of coffee brew. In the present study, physical characteristics such as bean density, brightness, titratable acidity, pH, moisture, and total soluble solids and also chemical composition, namely, caffeine, chlorogenic acids, lipids, sucrose, total polyphenols, and proteins, were evaluated in defective as well as in graded green coffee beans. The physical parameters such as weight, density, and brightness of defective coffee beans were low compared to the graded beans, which is due to the presence of immature, broken, bleached, and black beans. Caffeine content was low in triage beans compared to graded beans. Chlorogenic acids, one of the composition in coffee responsible for antioxidant activity, was found to be intact (marginally high in some cases) in defective coffee beans. Hence, triage coffee beans can be evaluated as a source of antioxidant or radical scavenging conserve for food systems. [source] Willow genotype, but not drought treatment, affects foliar phenolic concentrations and leaf-beetle resistanceENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2004Carolyn Glynn Abstract In a greenhouse experiment we examined the effect of willow genotype and irrigation regime (moderate drought and well-watered) on plant growth parameters, foliar nitrogen, and phenolic concentrations, as well as on the preference and performance of the blue leaf beetle, Phratora vulgatissima (L.) (Coleoptera: Chrysomelidae). The 10 vegetatively propagated willow genotypes in the experiments were F2 full-sibling hybrids, originated from a cross between Salix viminalis (L.) (Salicaceae) (high in condensed tannins) and Salix dasyclados (L.) (Salicaceae) (rich in phenolic glycosides). Insect bioassays were conducted on detached leaves in Petri dishes as well as with free-living insects on intact potted plants. The 10-week long irrigation treatments caused statistically significant phenotypic differences in the potted willow saplings. Total biomass was somewhat higher in the well-watered treatment. The root to total biomass ratio was higher in the drought-treatment plants. There was significant genotypic variation in foliar nitrogen concentrations, and they were higher in the drought-treatment plants. There was also a strong genotypic variation in each of the phenolic substances analyzed. Condensed tannins, which accounted for the greatest proportion of total phenolic mass, were higher in the well-watered treatment. There was, however, no difference in levels of the other phenolics (salicylates, cinnamic acid, flavonoids, and chlorogenic acid) between irrigation treatments. The sum of these phenolics was higher in the well-watered treatment. There was a strong variation in P. vulgatissima larval development on different willow genotypes, and larval performance was negatively correlated with levels of salicylates and cinnamic acid. There was, however, no effect of irrigation treatment on larval performance. Phratora vulgatissima preferred to feed on well-watered plants, and we found a preference for oviposition there, but neither feeding nor oviposition site preference was affected by willow genotype. Adult feeding and oviposition preferences were not correlated with larval performance. [source] Naturally occurring polyphenolic antioxidants modulate IgE-mediated mast cell activationIMMUNOLOGY, Issue 4 2000S.-S. Chen Summary Reactive oxygen species (ROS) are known to modulate activities of a host of kinases, phosphatases and transcription factors. Rutin and chlorogenic acid (CGA) are the major polyphenolic antioxidants present in the small molecular fraction of smokeless tobacco leaf extracts, as ascertained by reverse-phase high-pressure liquid chromatography (HPLC) and mass spectrometry. Levels of intracellular ROS in resting versus antigen,immunoglobulin E (IgE)-challenged murine mast cells were measured at 510 nm by fluorescence-activated cell sorting (FACS) using carboxy-dichlorofluorescein (DCFH-DA). Enhanced ROS production was observed in IgE-sensitized mast cells following antigenic challenge. Rutin and CGA reduced ROS levels in antigen,IgE-activated mast cells. Concomitantly, they also profoundly inhibited histamine release by these activated mast cells. In contrast, rutin and CGA augmented the inducible cytokine messages, i.e. interleukin (IL)-10, IL-13, interferon-, (IFN-,), IL-6 and tumour necrosis factor-, (TNF-,) in IgE-sensitized mast cells following antigen challenge. This study indicates that tobacco polyphenolic antioxidants that quench intracellular ROS, differentially affect two effector functions of antigen,IgE-activated mast cells. This model system may be employed to determine the molecular target of polyphenols. The potential role of these polyphenolic antioxidants on IgE-mediated allergy in vivo depends on a balance of their differential effects on mast cell activation. [source] Polyphenolic profile and antioxidant activity of five apple cultivars grown under organic and conventional agricultural practicesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2009Athanasios Valavanidis Summary The polyphenols and total antioxidant activities of five apple cultivars, grown by organic and conventional agricultural methods in neighbouring farms, were determined and compared. Total polyphenols in the whole fruit and in the peel were determined by the Folin-Ciocalteu method, and the total antioxidant activity was determined by three established methods, diphenyl picrylhydrazyl (DPPH), azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and ferric reducing/antioxidant power (FRAP). Polyphenolic content for the whole fruit was in the range of 80,196 and for the peel 165,400 (mg Gallic Acid Equivalent (GAE)/100 g fresh weight) for both types of agricultural practices. Antioxidant activities of fruit extracts were also relatively similar and well correlated to their polyphenolic content. High-performance liquid chromatography (HPLC) analysis of the most important polyphenolics (chlorogenic acid, catechin, epicatechin, procyanidin B1 and B2, cyaniding 3-galactoside, phloridzin, quercetin 3-galactoside and quercetin 3-arabinoside) also showed that concentrations do not differentiate significantly between the organic and conventional apples. Statistical significance of differences in antioxidant activities among the same cultivars was relatively small (flesh + peel or peel only) for both types of apples. These results indicate that organic apples do not present higher antioxidant or nutritional value compared with conventionally grown ones, as far as polyphenolic content and total antioxidant activities are concerned. [source] The nonconserved N-terminus of protein phosphatase 2B confers its properties to protein phosphatase 1IUBMB LIFE, Issue 2 2009Xiu-Jie Xie Abstract The protein phosphatase 1 catalytic subunit (PP1c) and the protein phosphatase 2B (PP2B or calcineurin) catalytic subunit (CNA) contain nonconserved N-terminal regions followed by conserved phosphatase cores. To examine the role of the N-termini of these two phosphatases, we substituted the residues 1,8 of PP1c with residues 1,42 of CNA, which is designated CNA(1-42)-PP1(9-330). The activities of CNA(1-42)-PP1(9-330) were similar to those of PP2B and different from those of PP1. The chimera was at least fourfold less sensitive to inhibition by okadaic acid, but was stimulated by nickel ions and chlorogenic acid, characteristics of PP2B not of PP1. These observations suggest that the N-terminus of CNA shifts the properties of PP1 toward those of PP2B. Our findings provide evidence that the nonconserved N-terminus of PP2B not only functions as important regulatory domain but also confers itself particular characteristics. This region may be targeted for regulation of PP2B activities in vivo. © 2008 IUBMB IUBMB Life, 61(2): 178,183, 2009 [source] EVALUATION OF RED CURRANTS (RIBES RUBRUM L.), BLACK CURRANTS (RIBES NIGRUM L.), RED AND GREEN GOOSEBERRIES (RIBES UVA-CRISPA) FOR POTENTIAL MANAGEMENT OF TYPE 2 DIABETES AND HYPERTENSION USING IN VITRO MODELSJOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2010MARCIA DA SILVA PINTO ABSTRACT Red currants (Ribes rubrum L.), black currants (Ribes nigrum L.), red and green gooseberries (Ribes uva-crispa) were evaluated for the total phenolics, antioxidant capacity based on 2, 2-diphenyl-1-picrylhydrazyl radical scavenging assay and functionality such as in vitro inhibition of ,-amylase, ,-glucosidase and angiotensin I-converting enzyme (ACE) relevant for potential management of hyperglycemia and hypertension. The total phenolics content ranged from 3.2 (green gooseberries) to 13.5 (black currants) mg/g fruit fresh weight. No correlation was found between total phenolics and antioxidant activity. The major phenolic compounds were quercetin derivatives (black currants and green gooseberries) and chlorogenic acid (red currants and red gooseberries). Red currants had the highest ,-glucosidase, ,-amylase and ACE inhibitory activities. Therefore red currants could be good dietary sources with potential antidiabetes and antihypertension functionality to compliment overall dietary management of early stages of type 2 diabetes. [source] Radical Scavenging Activity and Phenolic Compounds in Persimmon (Diospyros kaki L. cv. Mopan)JOURNAL OF FOOD SCIENCE, Issue 1 2008X.N. Chen ABSTRACT:, The Mopan persimmon (Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 ,m trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly (P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations (R2= 0.993, P < 0.05, ABTS radical; R2= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated (R2= 0.831, P < 0.05, ABTS radical; R2= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato. [source] Methodology Optimization for Quantification of Total Phenolics and Individual Phenolic Acids in Sweetpotato (Ipomoea batatas L.) RootsJOURNAL OF FOOD SCIENCE, Issue 7 2007M.S. Padda ABSTRACT:, Phenolic acids are one of the several classes of naturally occurring antioxidant compounds found in sweetpotatoes. Simplified, robust, and rapid methodologies were optimized to quantify total and individual phenolic acids in sweetpotato roots. Total phenolic acid content was quantified spectrophotometrically using both Folin,Denis and Folin,Ciocalteu reagents. The Folin,Ciocalteu reagent gave an overestimation of total phenolic acids due to the absorbance of interfering compounds (that is, reducing sugars and ascorbic acid). Individual phenolic acids were quantified by high-performance liquid chromatography (HPLC) using the latest in column technology. Four reversed-phase C18 analytical columns with different properties (dimensions, particle size, particle shape, pore size, and carbon load) were compared. Three different mobile phases using isocratic conditions were also evaluated. A column (4.6 × 150 mm) packed with 5-,m spherical silica particles of pore size 110 Ĺ combined with 14% carbon load provided the best and fast separation of individual phenolic acids (that is, chlorogenic acid, caffeic acid, and 3 isomers of dicaffeoylquinic acid) with a total analysis time of less than 7 min. Among the 3 mobile phases tested, a mobile phase consisting of 1% (v/v) formic acid aqueous solution: acetonitrile: 2-propanol, pH 2.5 (70:22:8, v/v/v) gave adequate separation. Among the solvents tested, aqueous mixtures (80:20, solvent:water) of methanol and ethanol provided higher phenolic acid extraction efficiency than the aqueous mixture of acetone. [source] Phenolic Acid Content and Composition in Leaves and Roots of Common Commercial Sweetpotato (Ipomea batatas L.) Cultivars in the United StatesJOURNAL OF FOOD SCIENCE, Issue 6 2007V.-D. Truong ABSTRACT:, Phenolic acids in commercially important sweet potato cultivars grown in the United States were analyzed using reversed-phase high-performance liquid chromatography (HPLC). Caffeic acid, chlorogenic acid, 4,5-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 3,4-di-O-caffeoylquinic acid were well separated with an isocratic elution in less than 25 min compared to about 120 min for analyzing and re-equilibrating the column with a gradient method. The isocratic elution order of these caffeoylquinic acid derivatives was confirmed by LC-MS/MS. Chlorogenic acid was the highest in root tissues, while 3,5-di-O-caffeoylquinic acid and/or 4,5-di-O-caffeoylquinic acid were predominant in the leaves. Steam cooking resulted in statistically nonsignificant increases in the concentration of total phenolics and all the individual phenolic acids identified. Sweetpotato leaves had the highest phenolic acid content followed by the peel, whole root, and flesh tissues. However, there was no significant difference in the total phenolic content and antioxidant activity between purees made from the whole and peeled sweet potatoes. [source] Changes in Radical-scavenging Activity and Components of Mulberry Fruit During MaturationJOURNAL OF FOOD SCIENCE, Issue 1 2006Tomoyuki Oki ABSTRACT Extracts of mulberry fruits (Morus sp.) were prepared from 8 cultivars harvested at 4 stages of maturity, and their radicalscavenging activity, anthocyanin content, and total phenolic content were measured. The radical-scavenging activity was evaluated by a spectrophotometric assay using the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in a 96-well microplate. Mulberry fruit extracts exhibited the DPPH-scavenging activities, ranging from 2.5 to 20.3 ,mol-Trolox equiv/g-FW. Their activities were variable during maturation, and the highest activity was observed in the fully mature mulberry fruit in all cultivars. Anthocyanin was scarcely present in the immature mulberry fruits; however, its content increased as the fruit matured in all cultivars. On the other hand, all immature mulberry fruits contained non-anthocyanin phenolic compound. An on-line high-performance liquid chromatography (HPLC) method for the detection of DPPH-scavenging compounds revealed the difference in predominant radical scavengers between the immature and fully mature stages in the Miran 5 cultivar. Four major radical scavengers in the Miran 5 cultivar were assigned to 2 caffeoylquinic acids (chlorogenic acid and its isomer) and 2 anthocyanins (cyanidin 3-glucoside and cyanidin 3-rutinoside) in the immature and fully mature stages, respectively, by LC-ESI-MS/MS analysis. The change in the content of 4 compounds in mulberry fruits during maturation demonstrated that the most likely contributors to the DPPH-scavenging activity were caffeoylquinic acids in the immature mulberry and anthocyanins in the mature and fully mature mulberry. [source] Quantitative analysis of the major constituents of St John's wort with HPLC-ESI-MSJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 12 2005Dhammitha H. Chandrasekera A method was developed to profile the major constituents of St John's wort extracts using highperformance liquid chromatography-electrospray mass spectrometry (HPLC-ESI-MS). The objective was to simultaneously separate, identify and quantify hyperforin, hypericin, pseudohypericin, rutin, hyperoside, isoquercetrin, quercitrin and chlorogenic acid using HPLC-MS. Quantification was performed using an external standardisation method with reference standards. The method consisted of two protocols: one for the analysis of flavonoids and glycosides and the other for the analysis of the more lipophilic hypericins and hyperforin. Both protocols used a reverse phase Luna phenyl hexyl column. The separation of the flavonoids and glycosides was achieved within 35 min and that of the hypericins and hyperforin within 9 min. The linear response range in ESI-MS was established for each compound and all had linear regression coefficient values greater than 0.97. Both protocols proved to be very specific for the constituents analysed. MS analysis showed no other signals within the analyte peaks. The method was robust and applicable to alcoholic tinctures, tablet/capsule extracts in various solvents and herb extracts. The method was applied to evaluate the phytopharmaceutical quality of St John's wort preparations available in the UK in order to test the method and investigate if they contain at least the main constituents and at what concentrations. [source] Chemical Characterization and Biological Activity of Macfadyena unguis-cati (Bignoniaceae)JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 3 2000D. S. DUARTE Macfadyena unguis-cati (L.) has been widely used in folk medicine as an anti-inflammatory, antimalarial and antivenereal. The purpose of this study was to chemically characterize the main plant components, and to evaluate the biological properties of some of the fractions derived from leaves (MACb) and liana (MACa) of this plant. Chemical characterization allowed the identification of the compounds corymboside, vicenin-2, quercitrin, chlorogenic acid, isochlorogenic acid, lupeol, ,-sitosterol, ,-sitosterylglucoside, allantoin and lapachol. The biological screening of fractions and/or purified substances derived from fractions revealed antitumoral and antitrypanosomal activities in fractions MACa/lapachol and MACb/MACb21, respectively. The anti-lipoxygenase and anti-cyclooxygenase effect seen in fractions MACa and MACb showed a partial correlation with the anti-inflammatory property attributed to this plant. [source] Nitrogen effects on total flavonoids, chlorogenic acid, and antioxidant activity of the medicinal plant Chrysanthemum morifoliumJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2010Dahui Liu Abstract Chrysanthemum morifolium (Ramat.) has a long history of cultivation and use as a traditional medicine and tea plant in China. A greenhouse experiment with potted soil,quarz mixture studied the effects of nitrogen supply (0, 56, 112, 167, 224, 334, 501, 556, and 668 mg N,kg,1) on concentrations and ratios of total flavonoids and chlorogenic acid in the flowers of C. morifolium using spectrophotometric and HPLC methods. The antioxidant activity of the flowers was determined as the radical scavenging activities of hydroxyl, superoxide anion, and 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) free radicals. A high N supply decreased the concentrations of total flavonoids by 18%,35% and that of chlorogenic acid by 8%,60% compared to a low N-supply rate. At the same time, increasing N supply significantly decreased the antioxidant activity of the flowers. The antioxidant activity of C. morifolium flowers was significantly positively correlated with the concentrations of total flavonoids and chlorogenic acid. We conclude that an N supply in excess of 300 mg (kg soil),1 will negatively affect the antioxidant activity and thereby reduce the quality of C. morifolium flowers. [source] Influence of flowering stage of Lonicera japonica Thunb. on variation in volatiles and chlorogenic acid.JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2009Geng Wu, Li-Mei Wang, Long-Jiang Yu., Mao-Teng Li, Ming-Zhang Ao, You-Yu Yan The original article to which this Erratum refers was published in Journal of the Science of Food and Agriculture 2009: 89: 953,957 [source] Sunflower proteins: overview of their physicochemical, structural and functional propertiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 12 2007Sergio González-Pérez Abstract There is increasing worldwide demand for proteins of both animal and plant origin. However, animal proteins are expensive in terms of both market price and environmental impact. Among alternative plant proteins, sunflower seeds are particularly interesting in view of their widespread availability in areas where soy is not or only sparsely produced. Compared with other sources of vegetable proteins, sunflower seeds have been reported to have a low content of antinutritional factors. Although the absence of these factors is important, the functionality of the protein preparations will mainly determine their applicability. This review provides detailed information about sunflower seed composition and processing, including processes to remove phenolic compounds from meals. The main part of the review concerns the structure and functionality of the two major protein fractions, helianthinin and 2S albumins. Regarding functionality, emphasis is on solubility, thermal behaviour and surface activity. Protein structure and functionality are discussed as a function of extrinsic factors such as pH, ionic strength, temperature and the presence of other seed components, particularly chlorogenic acid. In addition, sunflower proteins are compared from a structural and functional point of view with other plant proteins, particularly soy proteins. Copyright © 2007 Society of Chemical Industry [source] Modelling the effect of superatmospheric oxygen concentrations on in vitro mushroom PPO activity,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Perla A Gómez Abstract The kinetics of polyphenol oxidase (PPO, EC 1.14.18.1) with respect to oxygen concentrations from 5 to 100% using chlorogenic acid (CGA) as substrate was examined. In vitro mushroom PPO activity was determined by measuring the consumption of oxygen during the oxidation reaction. A differential Michaelis,Menten model was fitted to the obtained total depletion curves. The product concentration as well as the concentration of oxygen had a clear inhibitory effect on the reaction rate. However, the inhibitory effect of oxygen was more evident at low product concentration. A linear mixed inhibition model that considered both the product (oxidised CGA) and oxygen as inhibitors was developed. A model with the product as a competitive inhibitor and oxygen as an uncompetitive inhibitor was the most appropriate to explain the reaction kinetics. The values of the inhibition constants calculated from the model were 0.0032 mmol L,1 for Km (Michaelis,Menten constant related to oxygen), 0.023 mmol L,1 for Kmc (constant for competitive inhibition due to the product), 1.630 mmol L,1 for Kmu (constant for uncompetitive inhibition due to oxygen) and 1.77 × 10,4 mmol L,1 s,1 for Vmax (maximum reaction rate). The results indicate that superatmospheric oxygen concentrations could be effective in preventing enzymatic browning by PPO. Copyright © 2006 Society of Chemical Industry [source] Influence of branch bending on sugar, organic acid and phenolic content in fruits of ,Williams' pears (Pyrus communis L.)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2006Mateja Colaric Abstract Selected sugars, organic acids and phenolic compounds were analysed in mature fruits of ,Williams' pears using high-performance liquid chromatography. Fruits were harvested from the branches of trees tested in three treatments: branches were bent in summer 2003 (1 September), in spring 2004 (15 May) and control (branches were not bent). Pears contained up to 73.54 g kg,1 fresh weight (FW) of fructose, 9.42 g kg,1 FW of glucose, 7.94 g kg,1 FW of sucrose and 24.59 g kg,1 FW of sorbitol. Major organic acids were (in order of descending quantity) citric, malic, shikimic and fumaric acid (up to 3.05 g kg,1 FW, 2.24 g kg,1 FW, 71.79 mg kg,1 FW and 0.49 mg kg,1 FW, respectively). Chlorogenic acid (280.86,357.34 mg kg,1 FW) was the predominant phenolic acid, followed in concentration (mg kg,1 FW) by syringic acid (95.46,131.32), epicatechin (46.55,83.09), catechin (25.67,44.81), vanillic acid (1.87,3.48), sinapic acid (0.83,1.72) and caffeic acid (0.72,1.04). Significant differences in content of fructose, sorbitol, total sugars, catechin, epicatechin, sinapic acid, syringic acid, and a sum of determined phenolic compounds were observed among the treatments. Fruits from summer bending branches had the lowest content of individual sugars, citric acid and phenolic compounds and the highest content of malic, shikimic and fumaric acid. The highest content of fructose, sorbitol, sucrose, total sugars, caffeic acid, catechin, epicatechin and syringic acid were determined in the fruits from the spring treatment. In the control treatment the highest content of glucose, citric acid, chlorogenic acid, sinapic acid, vanillic acid, as well a sum of determined phenolics, were observed. The lowest content of fumaric acid was in the spring treatment and of malic and shikimic acid in the control. Copyright © 2006 Society of Chemical Industry [source] Phenolic compounds in some apple (Malus domestica Borkh) cultivars of organic and integrated productionJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2005Robert Veberic Abstract Eleven organically grown apple cultivars and 11 apple cultivars of integrated production from Austria and Slovenia were analyzed by HPLC for the content of phenolic compounds in peel and pulp. We identified chlorogenic acid, p -coumaric acid, procyanidin B3, protocatechuic acid, (,)-epicatechin, phloridzin, rutin and quercetin-3-rhamnoside in apple peel. In apple pulp, (+)-catechin was also identified in all the cultivars. Some other phenols (procyanidin B3, rutin and quercetin-3-rhamnoside) could not be identified or were not properly separated. With regard to the phenolic content in the apple peel, there were no differences between organically grown apple cultivars and apple cultivars of integrated production. Organically grown apples, however, exhibited a higher content of phenolic substances in the apple pulp compared with the apple cultivars of integrated production. This may be due either to the different genotype source or to the growing technology. Higher concentrations of phenolic compounds in organically grown cultivars could be a result of plant response to stress. The apple peel contained higher concentrations of identified phenols than the pulp. The apple peel represents up to 10% of the whole fruit; therefore the phenolsic compounds in the pulp are of greater importance to the consumer than the phenolic compounds in the peel. Copyright © 2005 Society of Chemical Industry [source] Free-radical scavenging activity of wormwood (Artemisia absinthium L) extractsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2005Jasna M Canadanovic-Brunet Abstract In an effort to discover new antioxidant natural compounds, wormwood (Artemisia absinthium L) an aromatic-bitter herb, was screened. The sequential extraction was realized with five solvents of different polarities (70% methanol, petroleum ether, chloroform, ethyl acetate, n -butanol). The antioxidative activity was tested by measuring their ability to scavenge stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and reactive hydroxyl radical during the Fenton reaction trapped by 5,5-dimethyl-1-pyrroline- N -oxide (DMPO), using electron spin resonance (ESR) spectroscopy. Results demonstrated that the antiradical and antioxidative activity depend on the type and concentration of applied extracts and increased in the order ethyl acetate > methanol > n -butanol > chloroform > petroleum ether > remaining water extracts. The investigation showed that the antiradical activity increased with increasing concentration of all extracts. The high contents of total phenolic compounds (25.6 mg g,1) and total flavonoids (13.06 mg g,1) indicated that these compounds contribute to the antiradical and antioxidative activity. In a model system, the formation of o -semiquinone radicals from quercetin and chlorogenic acid was obtained to prove the mechanism (hydrogen donating and/or one-electron reduction) of free-radical scavenging activity. Copyright © 2004 Society of Chemical Industry [source] Comparative study of six pear cultivars in terms of their phenolic and vitamin C contents and antioxidant capacityJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2003Andrea C Galvis Sánchez Abstract The main phenolic compounds in six pear cultivars were identified and quantified using high-performance liquid chromatography/diode array detection (HPLC/DAD) and HPLC/electrospray ionisation mass spectrometry (HPLC/ESIMS). Major quantitative differences were found in the phenolic profiles. The peel contained higher concentrations of chlorogenic acid, flavonols and arbutin than the flesh, where only chlorogenic acid was detected. Total phenolics ranged from 1235 to 2005 mg kg,1 in the peel and from 28 to 81 mg k g,1 in the flesh. Ascorbic acid and dehydroascorbic acid were detected in the peel, whereas only dehydroascorbic acid was present in the flesh. The ranges of vitamin C content were from 116 to 228 mg kg,1 in the peel and from 28 to 53 mg kg,1 in the flesh. The antioxidant capacity was correlated with the content of chlorogenic acid (r = 0.46), while ascorbic acid made only a small contribution to the total antioxidant capacity of the fruit. Copyright © 2003 Society of Chemical Industry [source] Phenolic compounds, lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2002Isabel Martínez-Valverde Abstract Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p -coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59,mg,kg,1 fresh weight, while naringenin levels were lower than 12.55,mg,kg,1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32,mg,kg,1 fresh weight, followed by caffeic acid, while p -coumaric and ferulic acids showed similar concentrations lower than 5,mg,kg,1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50,mg,kg,1 fresh weight), while the concentration in the other varieties was between 50 and 30,mg,kg,1, with the exception of Liso (less than 20,mg,kg,1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry [source] Chemiluminescence determination of pharmacologically active compounds by capillary electrophoresisLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 6 2005Suqin Han Abstract A simple and rapid capillary electrophoresis with direct chemiluminescence method has been developed for the determination of five natural pharmacologically active compounds including rutin, protocatechuic aldehyde, chlorogenic acid, luteolin and protocatechuic acid. The luminol as a component of the separation electrolyte buffer was introduced at the head of the separation capillary. The separation of five compounds was carried out in a fused-silica capillary with 15.0 mmol/L tetraborate, 1.0 mmol/L SDS and 0.42 mmol/L luminol (pH 8.5). The analytes was determined by enhancing the chemiluminescence of luminol with 0.13 mmol/L K3Fe(CN)6 in 0.05 mol/L NaOH, which was introduced at the post-column stage. The voltage applied was 16 kV. Under the optimum conditions, the analytes were separated within 10 min. The excellent linearity was obtained over two to three orders of magnitude with a detection limit (signal:noise = 3) of 0.012,0.055 µmol/L for all five analytes. The method was successfully used in the analysis of pharmaceutical and biological samples, and the assay results were satisfactory. Copyright © 2005 John Wiley & Sons, Ltd. [source] Modulation of oxidative cell damage by reconstituted mixtures of phenolic apple juice extracts in human colon cell linesMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 4-5 2006Sandra Schaefer Abstract Diets rich in fruits and vegetables are associated with a lower risk of tumour induction in the intestine and other sites. Apple juice with high amounts of antioxidative phenolics might protect the intestine against reactive oxygen species-mediated cell damage. We investigated to which extent the preventive effectiveness of polyphenolic juice extracts is governed by the amounts of five major constituents (rutin, phloridzin, chlorogenic acid, caffeic acid and epicatechin). In human colon cell lines (Caco-2, HT29), reconstituted mixtures of these phenolics were investigated in comparison to the original juice extracts, originating from cider and table apples. Parameters studied were (oxidative) DNA damage (Comet assay), cellular redox status (dichlorofluorescein assay) and Trolox equivalent antioxidant capacity (TEAC). The TEAC of the reconstituted mixtures was higher compared to the respective original extracts (4.7,7.3 mM vs. 3.6,4.2 mM Trolox). After 24 h cell incubation, menadione-induced (oxidative) DNA damage was more effectively reduced by the reconstituted mixtures (1,100 ,g/mL, 24 h), as compared to the original extracts. In contrast, the cellular ROS level was reduced to a rather similar extent by original extracts and reconstituted mixtures. The results lead to the conclusion that the selected constituents in their authentic proportions substantially account for the antioxidative effectiveness of phenolic apple juice extracts. [source] Applied environmental stresses to enhance the levels of polyphenolics in leaves of hawthorn plantsPHYSIOLOGIA PLANTARUM, Issue 2 2004Ara Kirakosyan In this investigation, two species of Crataegus (hawthorn) were chosen because their polyphenolic constituents have recently received greater attention for the treatment of patients with severe heart disease. One-year-old plants of hawthorn (Crataegus laevigata and C. monogyna) were subjected to water-deficit (continuous water deprivation), cold (4°C), flooding (immersion of roots of plants in water) or herbivory (leaf removal) stress treatments (each of 10 days duration) in order to assess their effects on levels of polyphenolics, namely (-)-epicatechin, catechin, chlorogenic acid, vitexin, vitexin-2,,- O -rhamnoside, acetylvitexin-2,,- O -rhamnoside, hyperoside, quercetin, and rutin in the leaves. The working hypothesis followed is that one or more of these stress treatment will elicit increases in the levels of these polyphenolics. Cold stress causes increases in levels of vitexin-2,,- O -rhamnoside, acetylvitexin-2,,- O -rhamnoside, hyperoside, and quercetin in both Crataegus species. Water-deficit stress increased the productivity of chlorogenic acid, catechin, and (-)-epicatechin in both hawthorn species. Flooding and herbivory caused no net increases, and in some cases, decreases in levels of polyphenolics. These studies indicate that either water-deficit stress or cold stress treatments, or a combination of the two, can be used to enhance the levels of desired polyphenolics in the leaves of these two hawthorn species in a photobioreactor system. These results may have significance for hawthorn in adapting to water-deficit or cold stress and are important considerations for the use of hawthorn in the treatment of heart disease in humans. [source] Development of an HPLC-PAD-MS assay for the identification and quantification of major phenolic edelweiss (Leontopodium alpium Cass.) constituentsPHYTOCHEMICAL ANALYSIS, Issue 5 2006Stefan Schwaiger Abstract The analytical assessment of edelweiss (Leontopodium alpinum) herb extracts, used in traditional alpine medicine, has resulted in the development of a HPLC-PAD-MS method that allows baseline separation of almost all constituents. Peak assignment of 14 analytes was achieved by comparison of retention times, UV and mass spectra with those of reference compounds either commercially available (luteolin, apigenin and chlorogenic acid) or isolated from edelweiss plants by column chromatography. Ten of the isolated analytes were identified as the known natural products: quercetin-3- O - , - d -glucoside, luteolin-7- O - , - d -glucoside, luteolin-3,- O - , - d -glucoside, luteolin-4,- O - , - d -glucoside, apigenin-7- O - , - d -glucoside, 6-hydroxy-luteolin-7- O - , - d -glucoside, luteolin-7,4,-di- O - , - d -glucoside, chrysoeriol-7- O - , - d -glucoside, leontopodic acid and 3,5-dicaffeolyquinic acid. One analyte, 3,4,5-tri-(E)-caffeoly-d-glucaric acid proved to be a new natural product and was named leontopodic acid B. Structure elucidation was carried out by means of MS and NMR spectroscopy in all cases. The aerial plant parts of L. alpinum (capitula, inflorescence leaves, stems, stem leaves and leaves of the basal rosette) showed variable amounts of the above-mentioned constituents, although qualitative differences were not observable. Copyright © 2006 John Wiley & Sons, Ltd. [source] Hypoglycemic effect and chlorogenic acid content in two Cecropia speciesPHYTOTHERAPY RESEARCH, Issue 8 2005Pilar Nicasio Abstract The hypoglycemic effect of methanol leaf extracts from Cecropia obtusifolia and C. peltata was evaluated in healthy mice. A significant decrease (p < 0.05) in plasma glucose levels was recorded 2 and 4 h after a single oral administration of methanol extracts (1 g/kg). This effect was correlated with the chlorogenic acid contents in both species; C. peltata, containing 19.84 ± 1.64 mg of chlorogenic acid/g of dried leaves produced the highest decrease (D, 2,60 = 20.18, p < 0.05) of plasma glucose levels (52.8%). The extracts of C. obtusifolia from Tabasco and Veracruz, showed similar hypoglycemic effects (33.3% and 35.7%, respectively) and chlorogenic acid contents (Tukey0.05 = 1.8859) (13.3 ± 3.2 mg/g and 13.1 ± 1.6 mg/g, respectively). The hypoglycemic effect produced by different doses (0.1, 0.25, 0.50, 0.75 and 1 g/kg body wt, p.o.) of C. peltata showed a lineal relationship with chlorogenic acid content, reaching an ED50 = 0.540 g/kg body wt for extract, and an ED50 = 10.8 mg/kg body wt for chlorogenic acid. These results suggest that C. peltata is a better hypoglycemic agent than C. obtusifolia, and it could be considered for developing a phytomedicinal product to carry out clinical trials. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||