2001
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Kim S, Moldes D, Cavaco-Paulo A. Laccases for enzymatic colouration of unbleached cotton. Enzyme Microb Technol 2007. [DOI: 10.1016/j.enzmictec.2007.01.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2002
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Lam RYY, Woo AYH, Leung PS, Cheng CHK. Antioxidant Actions of Phenolic Compounds Found in Dietary Plants on Low-Density Lipoprotein and Erythrocytes in Vitro. J Am Coll Nutr 2007; 26:233-42. [PMID: 17634168 DOI: 10.1080/07315724.2007.10719606] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE There is increasing interest in the study of the antioxidant actions of plant phenolic compounds as evidence shows that consumption of plant products rich in these compounds contributes to protection from a number of ailments including cardiovascular diseases. In the present study, the antioxidant effects of selected phenolic compounds from dietary sources, namely barbaloin, 6-gingerol and rhapontin, were investigated. METHODS Low-density lipoprotein (LDL), erythrocytes and erythrocyte membranes were subjected to several in vitro oxidative systems. The antioxidant effects of the phenolic compounds were assessed by their abilities in inhibiting hemolysis and lipid peroxidation of LDL and erythrocyte membranes, and in protecting ATPase activities and protein sulfhydryl groups of erythrocyte membranes. RESULTS 6-Gingerol and rhapontin were found to exhibit strong inhibition against lipid peroxidation in LDL induced by 2,2'-azobis(2-amidinopropane) hydrochloride (AAPH) and hemin while barbaloin possessed weaker effects. A similar order of antioxidant potencies among the three compounds was observed on the lipid peroxidation of erythrocyte membranes in a tert-butylhydroperoxide (tBHP)/hemin oxidation system. On the other hand, barbaloin and rhapontin were comparatively stronger antioxidants than 6-gingerol in preventing AAPH-induced hemolysis of erythrocytes. Among the three compounds, only barbaloin protected Ca2+-ATPase and protein sulfhydryl groups on erythrocyte membranes against oxidative attack by tBHP/hemin. Interestingly, rhapontin demonstrated protective actions on Na+/K+-ATPase in a sulfhydryl group-independent manner under the same experimental conditions. CONCLUSIONS In view of their protective effects on LDL and erythrocytes against oxidative damage, these phenolic compounds might have potential applications in prooxidant state-related cardiovascular disorders.
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Affiliation(s)
- Rosanna Y Y Lam
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
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2003
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KULKARNI ANANDP, POLICEGOUDRA R, ARADHYA S. CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF SAPOTA (ACHRAS SAPOTA LINN.) FRUIT. J Food Biochem 2007. [DOI: 10.1111/j.1745-4514.2007.00122.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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2004
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Yazdanparast R, Ardestani A, Jamshidi S. Experimental diabetes treated with Achillea santolina: effect on pancreatic oxidative parameters. JOURNAL OF ETHNOPHARMACOLOGY 2007; 112:13-8. [PMID: 17336007 DOI: 10.1016/j.jep.2007.01.030] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 01/22/2007] [Accepted: 01/25/2007] [Indexed: 05/14/2023]
Abstract
Oxidative stress is produced under diabetic condition and is likely involved in progression of pancreatic damage found in diabetes. In the present study, we examined possible protective effect of Achillea santolina L. (Compositae) against pancreatic damage in streptozotocin (STZ)-treated diabetic rats. Achillea santolina extract (ASE) is used by the traditional healers in many part of Iraq, as a hypoglycaemic agent. We evaluated the effect of ASE on blood glucose level, serum nitric oxide (NO) concentration and the oxidative stress status in rat pancreatic tissue. STZ was injected intraperitonealy at a single dose of 40mgkg(-1) to induce diabetes. ASE (0.1g/kgday) was orally administered to a group of diabetic rats for 30 consecutive days. Results showed significant reduction in the activities of superoxide dismutase (SOD), catalase (CAT) and pancreatic glutathione (GSH) levels in the diabetic rats compared to the control subjects. On the other hand, blood glucose level, serum NO, malondialdehyde (MDA), a marker of lipid peroxidation, protein oxidation indices including protein carbonyl (PCO) and advanced oxidation protein products (AOPP) were significantly elevated in pancreas of the diabetic group. Treatment with ASE reduced blood glucose level, serum NO, pancreatic MDA, PCO and AOPP. In addition, the content of GSH was restored to the normal level of the control group. Furthermore, ASE significantly increased CAT and SOD activities in ASE-treated rats. Based on our data, it can be concluded that Achillea santolina have a high hypoglycaemic activity and this may be attributed to its antioxidative potential.
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Affiliation(s)
- Razieh Yazdanparast
- Institute of Biochemistry and Biophysics, P.O. Box 13145-1384, University of Tehran, Tehran, Iran.
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2005
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2006
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Ruuhola T, Salminen JP, Haviola S, Yang S, Rantala MJ. Immunological memory of mountain birches: effects of phenolics on performance of the autumnal moth depend on herbivory history of trees. J Chem Ecol 2007; 33:1160-76. [PMID: 17502999 DOI: 10.1007/s10886-007-9308-z] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Revised: 04/16/2007] [Accepted: 04/30/2007] [Indexed: 10/23/2022]
Abstract
Plants have been suggested to have an immunological memory comparable to animals. The evidence for this, however, is scarce. In our study with the mountain birch -- Epirrita autumnata system, we demonstrated that birches exposed as long as 5 yr to feeding of E. autumnata larvae (delayed induced resistance, DIR), responded more strongly to a new challenge than trees without an herbivory history. Pupal weights remained lower, and the duration of the larval period was prolonged in the DIR trees, although immunity, measured as an encapsulation rate, was not affected. We further demonstrated that the effects of birch phenolics on performance of E. autumnata were different in the exposed (DIR) trees from naive control trees, although we found only one significant change in chemistry. The quercetin:kaemferol ratio was increased in DIR trees, suggesting that herbivory caused oxidative stress in birches. In DIR trees, phenolics, especially hydrolyzable tannins (HTs), affected pupal weights negatively, whereas in control trees, the effects were either nonsignificant or positive. HTs also prolonged the duration of the larval period of females, whereas peroxidase (POD) activity prolonged that of males. We suggest that the causal explanation for the induced resistance was an enhanced oxidation of phenolic compounds from the DIR trees in the larval digestive tract. Phenolic oxidation produces semiquinones, quinones, free radicals, and ROS, which may have toxic, antinutritive, and/or repellent properties against herbivores.
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Affiliation(s)
- Teija Ruuhola
- Section of Ecology, Department of Biology, University of Turku, FI-20014, Turku, Finland.
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2007
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Xu D, Gao ZL, Li N, Li KA. Tris(2,2′-bipyridyl)ruthenium(II) electrochemiluminescence (ECL) enhanced by rutin on platinum electrode. CHINESE CHEM LETT 2007. [DOI: 10.1016/j.cclet.2007.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2008
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Zhang Y, Tie X, Bao B, Wu X, Zhang Y. Metabolism of flavone C-glucosides and p-coumaric acid from antioxidant of bamboo leaves (AOB) in rats. Br J Nutr 2007; 97:484-94. [PMID: 17313710 DOI: 10.1017/s0007114507336830] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The metabolism of flavone C-glucosides and p-coumaric acid from antioxidant of bamboo leaves (AOB) in rats is discussed systematically in the present study. Following single oral administration of AOB, p-coumaric acid was detected in plasma but not in gastrointestinal tract extracts and faeces, and the corresponding absorption pharmacokinetic curve at different time points showed a prolonged elimination phase with p-coumaric acid being detected in the kidneys and excreted as its original form (1 x 80 (sd 0 x 24) % and 1 x 90 (sd 0 x 26) % at 12 and 24 h, respectively). However, the four flavone C-glucosides orientin, homoorientin, vitexin and isovitexin were poorly absorbed in the gastrointestinal tract. More than 50 % recovery of flavone C-glucosides was determined at 12 h and faeces containing these four analytes (21 x 23 (sd 1 x 92) %) were excreted at 24 h. These data suggested that the effective time these compounds were in the colon was long enough so that they could exert their antioxidant activity and scavenge free radicals. Besides the excretion of the original forms, moieties of the flavone C-glucosides were hydrolysed by deglycosylation and the opening of the heterocyclic C ring. Some small molecules such as phloroglucinol (PG), hydrocaffeic acid (HCA) and phloretic acid (PA) were detected and identified as metabolites of the flavone C-glucosides. In the present work, we compared the metabolic fate of flavone C-glucosides to that of flavone O-glucosides in rats, and evaluated the absorption, tissue distribution and excretion of flavone C-glucosides in AOB on their metabolism for the first time.
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Affiliation(s)
- Yu Zhang
- Department of Food Science and Nurtition, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
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2009
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Abstract
Flavonoids, one of the most numerous and best studied groups of plant polyphenols, are well known to exhibit various biological and pharmacological effects. Functional artificial polymeric flavonoids, flavonoid polymers and amine containing polymer-flavonoid conjugates have been developed. The acid-catalyzed polymerization of catechin and aldehydes proceeds regioselectively to produce catechin-aldehyde polycondensates. Peroxidases and laccases catalyze the oxidative coupling of flavonoids and oxidative conjugation with polyamines. The resulting polymers show much higher antioxidant activities than the flavonoid monomers. In addition, these polymeric flavonoids efficiently inhibit disease related enzymes, such as xanthine oxidase, collagenase, elastase, hyaluronidase and tyrosinase. Based on these results, the molecular design for amplification of the biological and pharmacological properties of flavonoids is proposed.
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Affiliation(s)
- Hiroshi Uyama
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan.
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2010
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Xu B, Yuan S, Chang S. Comparative Analyses of Phenolic Composition, Antioxidant Capacity, and Color of Cool Season Legumes and Other Selected Food Legumes. J Food Sci 2007; 72:S167-77. [DOI: 10.1111/j.1750-3841.2006.00261.x] [Citation(s) in RCA: 232] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2011
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Xi J, Guo R. Interactions between flavonoids and hemoglobin in lecithin liposomes. Int J Biol Macromol 2007; 40:305-11. [PMID: 16997370 DOI: 10.1016/j.ijbiomac.2006.08.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2006] [Revised: 08/19/2006] [Accepted: 08/21/2006] [Indexed: 11/26/2022]
Abstract
In this paper, the binding of flavonoids (quercetin and rutin) to hemoglobin (Hb) have been investigated by fluorescence, absorption spectroscopy and circular dichroism (CD) spectroscopy. The binding parameters and binding mode between flavonoids and Hb are determined and the results of CD and synchronous fluorescence spectra indicate a conformational change of Hb with addition of flavonoids. The effects of lecithin liposomes on the binding parameter of quercetin and rutin to Hb are also studied. When incorporated into liposome, flavonoids can reduce the fluorescence of tryptophanyl residues of Hb to a lesser extent. The difference of the structure characteristics between quercetin and rutin has a significant effect on their binding affinity for Hb.
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Affiliation(s)
- Juqun Xi
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China
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2012
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Lante A, Crapisi A, Lomolino G, Spettoli P. Chemical parameters, biologically active polyphenols and sensory characteristics of some Italian organic wines. ACTA ACUST UNITED AC 2007. [DOI: 10.1080/09571260500142054] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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2013
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SARI F, TURKMEN N, POLAT G, VELIOGLU YS. Total Polyphenol, Antioxidant and Antibacterial Activities of Black Mate Tea. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2007. [DOI: 10.3136/fstr.13.265] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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2014
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de Brito ES, de Araújo MCP, Lin LZ, Harnly J. Determination of the flavonoid components of cashew apple ( Anacardium occidentale) by LC-DAD-ESI/MS. Food Chem 2007; 105:1112-1118. [PMID: 25544795 DOI: 10.1016/j.foodchem.2007.02.009] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Liquid chromatography, with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI/MS), was used to identify and quantify flavonoids in cashew apple. One anthocyanin and thirteen glycosylated flavonols were detected in a methanol-water extract. Among them, the 3-O-galactoside, 3-O-glucoside, 3-O-rhamnoside, 3-O-xylopyranoside, 3-O-arabinopyranoside and 3-O-arabinofuranoside of quercetin and myricetin, as well as kaempferol 3-O-glucoside were identified by direct comparison with standards or positively identified flavonoids in cranberry. The anthocyanin was the 3-O-hexoside of methyl-cyanidin. Trace amounts of delphinidin and rhamnetin were detected in the hydrolyzed extract, suggesting their glycosides were present, but undetectable, in the original extract. The concentrations of the 14 flavonoids in the tested sample were determined. This is the first report of these flavonoids in cashew apple.
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Affiliation(s)
- Edy Sousa de Brito
- Embrapa Tropical Agroindustry, R Dra Sara Mesquita, 2270, Fortaleza, CE 60511-110, Brazil
| | | | - Long-Ze Lin
- Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, USDA, 103000 Baltimore Avenue, Beltsville, MD 20705, United States
| | - James Harnly
- Food Composition Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, USDA, 103000 Baltimore Avenue, Beltsville, MD 20705, United States
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2015
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Sultana B, Anwar F, Przybylski R. Antioxidant potential of corncob extracts for stabilization of corn oil subjected to microwave heating. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.12.061] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2016
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Susanti D, Sirat HM, Ahmad F, Ali RM, Aimi N, Kitajima M. Antioxidant and cytotoxic flavonoids from the flowers of Melastoma malabathricum L. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.09.011] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2017
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Sultana B, Anwar F, Przybylski R. Antioxidant activity of phenolic components present in barks of Azadirachta indica, Terminalia arjuna, Acacia nilotica, and Eugenia jambolana Lam. trees. Food Chem 2007. [DOI: 10.1016/j.foodchem.2007.01.019] [Citation(s) in RCA: 272] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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2018
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Nakagawa K, Kaku M, Abukawa T, Aratani K, Yamaguchi M, Uesato S. Copper(II) Ions Convert Catechins from Antioxidants to Prooxidants in Protein Carbonyl Formation. ACTA ACUST UNITED AC 2007. [DOI: 10.1248/jhs.53.591] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Kazuo Nakagawa
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University
| | - Maiko Kaku
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University
| | - Tomomi Abukawa
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University
| | - Kanako Aratani
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University
| | - Mariko Yamaguchi
- Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University
| | - Shinichi Uesato
- Department of Biotechnology, Faculty of Engineering, Kansai University
- High Technology Research Center, Kansai University
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2019
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Abreu PM, Braham H, Ben Jannet H, Mighri Z, Matthew S. Antioxidant compounds from Ebenus pinnata. Fitoterapia 2007; 78:32-4. [PMID: 17067757 DOI: 10.1016/j.fitote.2006.09.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Accepted: 09/04/2006] [Indexed: 11/28/2022]
Abstract
Activity-guided fractionation of the methanol extract of Ebenus pinnata aerial parts led to the isolation of ombuoside (1), kaempferol 3-O-rutinoside (2), rutin (3), catechin (4), and picein (5), along with beta-sitosterol and beta-sitosterol glucoside. Compounds 1-4 showed significant antioxidant activity in the DPPH, and TEAC, reducing power assays.
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Affiliation(s)
- Pedro M Abreu
- REQUIMTE, Departamento de Química, FCT-UNL, 2829-516 Caparica, Portugal.
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2020
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Heo HJ, Kim YJ, Chung D, Kim DO. Antioxidant capacities of individual and combined phenolics in a model system. Food Chem 2007. [DOI: 10.1016/j.foodchem.2006.11.002] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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2021
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Lee KH, Chiang CK, Lin ZH, Chang HT. Determining enediol compounds in tea using surface-assisted laser desorption/ionization mass spectrometry with titanium dioxide nanoparticle matrices. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2007; 21:2023-30. [PMID: 17534856 DOI: 10.1002/rcm.3058] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We describe the use of titanium dioxide nanoparticles (TiO2 NPs) as selective probes and matrices for the determination of catechins using surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS). The interactions between the enediol compounds and TiO2 NPs were evident by the change in color of the TiO2 NP solution from milky white to orange. Through these interactions, the TiO2 NPs could be used to concentrate enediol compounds, including catechins and ascorbic acid. The limits of detection (LODs) for three catechins--catechin, (-)-epigallocatechin, and (-)-epigallocatechin gallate--at a signal-to-noise ratio of 3 were 0.45, 1.85 and 0.65 microM, respectively. The TiO2 NP matrices provide a number of advantages over conventional organic matrices (e.g. 2',4',6'-trihydroxyacetophenone), including ease of sample preparation, less background noise in the low-mass region, and high repeatability. The applicability of this method was confirmed through the high reproducibility of the determination of the two catechins in tea samples that had not been subjected to any sample preparation procedures (shot-to-shot variation: <10%).
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Affiliation(s)
- Kun-Hong Lee
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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2022
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2023
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A marginal contribution of selected carotenoids to the supression of UV-irradiation-induced lecithin peroxidation in hexane solution. JOURNAL OF THE SERBIAN CHEMICAL SOCIETY 2007. [DOI: 10.2298/jsc0703235c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The aim of this work was to study the anticipated antioxidant role of four selected carotenoids in mixtures with lecithin lipoidal compounds in hexane solution, under continuous UV-irradiation in three different ranges (UV-A, UV-B and UV-C). Two carotenes (b-carotene and licopene) and two xantophylls (lutein and neoxanthin) were employed to control the lipid peroxidation process generated by UV-irradiation, by scavenging the involved free radicals. The results show that while carotenoids undergo a substantial, structural dependent destruction (bleaching), which is highly dependent on energy of the UV-photons, their contribution to the expected suppression of lecithin peroxidation is of marginal importance, not exceeding a maximum of 20%. The marginal antioxidant behaviour has been attributed to a highly unordered hexane solution, where the scavenging action of the carotenoids becomes less competitive.
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2024
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Bioactive components of the hop strobilus: comparison of different extraction methods by capillary electrophoretic and chromatographic methods. J Chromatogr A 2006; 1155:222-9. [PMID: 17316654 DOI: 10.1016/j.chroma.2006.12.067] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Revised: 12/07/2006] [Accepted: 12/11/2006] [Indexed: 11/22/2022]
Abstract
In the present study, the composition of the hop strobilus extract by using different extraction methods under different solvent conditions was analysed and compared. Several separation methods were applied to obtaining detailed information about the hop extract: capillary zone electrophoresis (CZE), high-performance liquid chromatography-mass-spectrometry (HPLC-MS/MS) and gas chromatography-mass-spectrometry (GC-MS). The electropherograms of different extracts varied dramatically. The oxidation reaction of the hop strobilus extract was examined.
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2025
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Khlebnikov AI, Schepetkin IA, Domina NG, Kirpotina LN, Quinn MT. Improved quantitative structure-activity relationship models to predict antioxidant activity of flavonoids in chemical, enzymatic, and cellular systems. Bioorg Med Chem 2006; 15:1749-70. [PMID: 17166721 PMCID: PMC2013303 DOI: 10.1016/j.bmc.2006.11.037] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 11/17/2006] [Accepted: 11/27/2006] [Indexed: 10/23/2022]
Abstract
Quantitative structure-activity relationship (QSAR) models are useful in understanding how chemical structure relates to the biological activity of natural and synthetic chemicals and for design of newer and better therapeutics. In the present study, 46 flavonoids and related polyphenols were evaluated for direct/indirect antioxidant activity in three different assay systems of increasing complexity (chemical, enzymatic, and intact phagocytes). Based on these data, two different QSAR models were developed using (i) physicochemical and structural (PC&S) descriptors to generate multiparameter partial least squares (PLS) regression equations derived from optimized molecular structures of the tested compounds and (ii) a partial 3D comparison of the 46 compounds with local fingerprints obtained from fragments of the molecules by the frontal polygon (FP) method. We obtained much higher QSAR correlation coefficients (r) for flavonoid end-point antioxidant activity in all three assay systems using the FP method (0.966, 0.948, and 0.965 for datasets evaluated in the biochemical, enzymatic, and whole cell assay systems, respectively). Furthermore, high leave-one-out cross-validation coefficients (q2) of 0.907, 0.821, and 0.897 for these datasets, respectively, indicated enhanced predictive ability and robustness of the model. Using the FP method, structural fragments (submolecules) responsible for the end-point antioxidant activity in the three assay systems were also identified. To our knowledge, this is the first QSAR model derived for description of flavonoid direct/indirect antioxidant effects in a cellular system, and this model could form the basis for further drug development of flavonoid-like antioxidant compounds with therapeutic potential.
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Affiliation(s)
- Andrei I. Khlebnikov
- Department of Chemistry, Altai State Technical University, Barnaul 656038, Russia
- *Corresponding Authors: Dr. Andrei I. Khlebnikov, Department of Chemistry. Altai State Technical University. 46 Lenin Avenue. Barnaul 656038. Russia. Phone: +7-3852-245513; +7-3852-522436. Fax +7-3852-367864,
| | - Igor A. Schepetkin
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717, USA
| | - Nina G. Domina
- Department of Chemistry, Altai State Technical University, Barnaul 656038, Russia
| | - Liliya N. Kirpotina
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717, USA
| | - Mark T. Quinn
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, MT 59717, USA
- *Corresponding Authors: Dr. Andrei I. Khlebnikov, Department of Chemistry. Altai State Technical University. 46 Lenin Avenue. Barnaul 656038. Russia. Phone: +7-3852-245513; +7-3852-522436. Fax +7-3852-367864,
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2026
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García-Mediavilla V, Crespo I, Collado PS, Esteller A, Sánchez-Campos S, Tuñón MJ, González-Gallego J. The anti-inflammatory flavones quercetin and kaempferol cause inhibition of inducible nitric oxide synthase, cyclooxygenase-2 and reactive C-protein, and down-regulation of the nuclear factor kappaB pathway in Chang Liver cells. Eur J Pharmacol 2006; 557:221-9. [PMID: 17184768 DOI: 10.1016/j.ejphar.2006.11.014] [Citation(s) in RCA: 341] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 11/02/2006] [Accepted: 11/06/2006] [Indexed: 12/26/2022]
Abstract
We examined the ability of the flavonoids quercetin and kaempferol to modulate inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and reactive C-protein (CRP) expression, and to induce changes in the nuclear factor kappa B (NF-kappaB) pathway in the human hepatocyte-derived cell line Chang Liver. Cells were incubated with a cytokine mixture supplemented with quercetin or kaempferol (5 to 200 micromol/l). Kaempferol produced a significant concentration-dependent decrease of iNOS, COX-2 and CRP protein level at all concentrations, but the percentage of inhibition induced by quercetin was reduced at high concentrations. Both flavonoids significantly inhibited mRNA level of iNOS, COX-2, and CRP. Inhibitory effects by quercetin and kaempferol were also observed on NF-kappaB activation and on protein concentration of the phosphorylated form of the inhibitor IkappaB alpha and of IKK (IkappaB kinase)alpha. The present study suggests that the modulation of iNOS, COX-2 and CRP by quercetin or kaempferol may contribute to the anti-inflammatory effects of these two structurally similar flavonoids in Chang Liver cells, via mechanisms likely to involve blockade of NF-kappaB activation and the resultant up-regulation of the pro-inflammatory genes. Our data also indicate that the minor structural differences between both compounds determine differences in their inhibitory capacity.
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2027
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Hsu CL, Yen GC. Induction of cell apoptosis in 3T3-L1 pre-adipocytes by flavonoids is associated with their antioxidant activity. Mol Nutr Food Res 2006; 50:1072-9. [PMID: 17039455 DOI: 10.1002/mnfr.200600040] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Obesity is biologically characterized at the cellular level by an increase in the number and size of adipocytes differentiated from fibroblastic pre-adipocytes in adipose tissue. In this study, we focused on the relationship between the influence of flavonoids on cell population growth and their antioxidant activity. The results showed that the inhibition of flavonoids (naringenin, rutin, hesperidin, resveratrol, naringin and quercetin) on 3T3-L1 pre-adipocytes was 28.3, 8.1, 11.1, 33.2, 5.6 and 71.5%, respectively. In oxygen radical absorbance capacity (ORAC) assay, quercetin had the highest ORAC(ROO) value among the six flavonoids tested. Apoptosis assays showed that quercetin increased apoptotic cells in time- and dose-dependent manner. Treatment of cells with quercetin decreased the mitochondrial membrane potential in the courses of time and dose. The cell apoptosis/necrosis assay showed that quercetin increased the number of apoptotic cells, but not necrotic cells. Quercetin treatment of cells caused a significant time- and dose-dependent increase in the caspase-3 activity. Western analysis indicated that treatment of quercetin markedly down-regulated PARP and Bcl-2 proteins, and activated caspase-3, Bax, and Bak proteins. These results indicate that quercetin efficiently inhibits cell population growth and induction of apoptosis in 3T3-L1 pre-adipocytes.
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Affiliation(s)
- Chin-Lin Hsu
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan. Fax: +886-4-2285-4378
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2028
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Stevenson DE, Wibisono R, Jensen DJ, Stanley RA, Cooney JM. Direct acylation of flavonoid glycosides with phenolic acids catalysed by Candida antarctica lipase B (Novozym 435®). Enzyme Microb Technol 2006. [DOI: 10.1016/j.enzmictec.2006.03.006] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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2029
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Deng D, Zhang J, Cooney JM, Skinner MA, Adaim A, Jensen DJ, Stevenson DE. Methylated polyphenols are poor “chemical” antioxidants but can still effectively protect cells from hydrogen peroxide-induced cytotoxicity. FEBS Lett 2006; 580:5247-50. [PMID: 16962587 DOI: 10.1016/j.febslet.2006.08.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2006] [Revised: 08/11/2006] [Accepted: 08/24/2006] [Indexed: 11/20/2022]
Abstract
Several polyphenolic compounds, including flavonoids and phenolic acids, were compared with their per-methylated forms in both chemical and cell-based assays for antioxidant capacity. Methylation largely eliminated "chemical" antioxidant capacity, according to ferric reducing antioxidant power and oxygen radical absorbance capacity assays. Methylation, however, only moderately reduced protection of human Jurkat cells in culture, from hydrogen peroxide-mediated cytotoxicity, at physiologically relevant concentrations. Neither methylated nor un-methylated compounds were detectably metabolized by the cells. It appears that the protective mechanism of polyphenolic antioxidants against high concentrations of hydrogen peroxide in human cells may be largely unrelated to chemical antioxidant capacity.
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Affiliation(s)
- Dawei Deng
- HortResearch, The Horticulture and Food Research Institute of New Zealand, Private Bag 92-169, Mt Albert, Auckland, New Zealand
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2030
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Seyoum A, Asres K, El-Fiky FK. Structure-radical scavenging activity relationships of flavonoids. PHYTOCHEMISTRY 2006; 67:2058-70. [PMID: 16919302 DOI: 10.1016/j.phytochem.2006.07.002] [Citation(s) in RCA: 214] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2006] [Revised: 06/29/2006] [Accepted: 07/06/2006] [Indexed: 05/10/2023]
Abstract
The objective of this work is to establish the structural requirements of flavonoids for appreciable radical-scavenging activity (RSA) and elucidate a comprehensive mechanism that can explain their activity. To this end, the RSA of 52 flavonoids against 2,2-diphenyl-1-picrylhydrazyl was determined. The relative change in energy (DeltaH(f)) associated with the formation of various flavonoidal and other phenolic radicals and also the spin distribution in these radicals were determined using computational programmes. By correlating experimental data with DeltaH(f), structural features that affect activity have been identified and considered in perspective. It was shown with compelling evidences that the RSA of flavonoids could be mapped to one of their ring systems, making it possible to study their RSA by dissecting their structures and designing representative simpler models. Consequently, hydroxytoluene units were demonstrated to successfully account for the RSA of flavonoids due to ring B and also to satisfactorily do so for activities due to ring A. Further, a comprehensive model for the radical scavenging reactions of flavonoids (and in general, phenolic compounds), which could account for hydrogen atom donation and the termination of aroxyl radicals, was proposed. Finally, prediction of structural features that could endow flavonoids with appreciable radical scavenging capability was made by considering the stability data and the ease of termination. In conclusion, the underlying molecular phenomena of the RSA of flavonoids could be explained by the ease of hydrogen atom abstraction and the ease of the termination of the flavonoidal aroxyl radicals.
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Affiliation(s)
- Ameha Seyoum
- Department of Pharmacognosy, School of Pharmacy, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
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2031
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Srichairatanakool S, Ounjaijean S, Thephinlap C, Khansuwan U, Phisalpong C, Fucharoen S. Iron-chelating and free-radical scavenging activities of microwave-processed green tea in iron overload. Hemoglobin 2006; 30:311-27. [PMID: 16798656 DOI: 10.1080/03630260600642666] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Secondary iron overload is found in beta-thalassemia (thal) patients because of increased dietary iron absorption and multiple blood transfusions. Excessive iron catalyzes free-radical generation, leading to oxidative damage and vital organ dysfunction. Non-transferrin-bound iron (NTBI) detected in thalassemic plasma is highly toxic and chelatable. Though used to treat iron overload, desferrioxamine (DFO) and deferiprone (L1) also have adverse effects. Green tea (GT) shows many pharmacological effects, particularly antioxidative and iron-chelating capacities. This study was performed to investigate the ability of GT extracts to reduce plasma NTBI concentration and oxidative stress in vitro. The Fe(3+) was found to bind to GT crude extract and form a complex. Green tea crude extract time- and dose-dependently decreased plasma NTBI concentration and counteracted the increase of oxidative stress in both Fe(2+)-EDTA-treated human plasma and erythrocytes. Green tea is a bifunctional natural product that could be relevant for management of iron overload and oxidative stress.
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2032
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Frazier RA, Papadopoulou A, Green RJ. Isothermal titration calorimetry study of epicatechin binding to serum albumin. J Pharm Biomed Anal 2006; 41:1602-5. [PMID: 16522360 DOI: 10.1016/j.jpba.2006.02.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Revised: 01/31/2006] [Accepted: 02/01/2006] [Indexed: 11/24/2022]
Abstract
The interaction of epicatechin with bovine serum albumin (BSA) was studied by isothermal titration calorimetry. The binding constant (K) and associated thermodynamic binding parameters (n, DeltaH) were determined for the interaction at three solution concentrations of BSA using a binding model assuming independent binding sites. These data show weak non-covalent binding of epicatechin to BSA. The interaction energetics varied with BSA concentration in the calorimeter cell, suggesting that the binding of epicatechin induced BSA aggregation. The free energy (DeltaG) remained constant within a range of 2 kJ mol(-1) and negative entropy was observed, indicating an enthalpy driven exothermic interaction. It is concluded that the non-covalent epicatechin-BSA complex is formed by hydrogen bonding.
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Affiliation(s)
- Richard A Frazier
- School of Food Biosciences, The University of Reading, P.O. Box 226, Whiteknights, Reading RG6 6AP, United Kingdom.
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2033
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Liu Y, Lai X, Ling X, Zhao Y, Cui J. Interactions Between Thrombin with Flavonoids from Abelmoschus manihot (L.) Medicus by CZE. Chromatographia 2006. [DOI: 10.1365/s10337-006-0841-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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2034
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Blasa M, Candiracci M, Accorsi A, Piacentini MP, Albertini MC, Piatti E. Raw Millefiori honey is packed full of antioxidants. Food Chem 2006. [DOI: 10.1016/j.foodchem.2005.03.039] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2035
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Wang CZ, Fishbein A, Aung HH, Mehendale SR, Chang WT, Xie JT, Li J, Yuan CS. Polyphenol contents in grape-seed extracts correlate with antipica effects in cisplatin-treated rats. J Altern Complement Med 2006; 11:1059-65. [PMID: 16398598 DOI: 10.1089/acm.2005.11.1059] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Grape-seed (Vitis spp.) extract (GSE) is a widely used antioxidant dietary supplement. Chemotherapeutic agents such as cisplatin induce oxidative damage in the gastrointestinal tract and cause nausea and vomiting. MATERIALS AND METHODS A rat model of simulated emesis was used to observe that cisplatin significantly increased kaolin consumption (or pica). Three GSEs from different sources were used in this study. RESULTS High-performance liquid chromatographic analysis of five major constituents (gallic acid, catechin, epicatechi, procyanidin B2, and epicatechin gallate) revealed that each constituent had different levels in the three GSEs. Extract #1, prepared in the laboratory of the investigators, had the lowest total polyphenol content (27.27 mg/g); Extract #2, obtained from a dietary supplement company in the United States, had a somewhat higher level (35.84 mg/g); and Extract #3, obtained from China, had the highest level (194.21 mg/g). Subsequently these GSEs were intraperitoneally administered in rats to evaluate their ability to decreasing cisplatin induced pica. At 10 mg/kg all three GSEs, with varying degrees of effect, decreased cisplatin-induced pica. The areas under the curves of kaolin intake from time 0 to 72 hours, compared to those in the cisplantin-only group, were reduced 45% for Extract #1 (p < 0.01), 54% for Extract #2 (p < 0.01), and 66% Extract #3 (p < 0.001). CONCLUSIONS The study data showed variable polyphenol contents and proportions in the three GSEs correlated to variable pharmacologic effects, indicating the importance of standardization of herbal product preparations. However further increasing of the GSE doses reversed the antipica effects of GSEs, probably because of their pro-oxidant effects. Results from this study suggest that an appropriate dose of GSE has therapeutic value in treating cisplatin-induced emesis.
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Affiliation(s)
- Chong-Zhi Wang
- Tang Center for Herbal Medicine Research, Pritzker School of Medicine, University of Chicago, IL 60637, USA
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2036
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Weber KC, Honório KM, Bruni AT, Andricopulo AD, da Silva ABF. A partial least squares regression study with antioxidant flavonoid compounds. Struct Chem 2006. [DOI: 10.1007/s11224-006-9048-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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2037
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Harris GK, Qian Y, Leonard SS, Sbarra DC, Shi X. Luteolin and chrysin differentially inhibit cyclooxygenase-2 expression and scavenge reactive oxygen species but similarly inhibit prostaglandin-E2 formation in RAW 264.7 cells. J Nutr 2006; 136:1517-21. [PMID: 16702314 DOI: 10.1093/jn/136.6.1517] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Inflammation and oxidative stress are associated with cancer, atherosclerosis, and other chronic diseases. Dietary flavonoids have been reported to possess antiinflammatory and antioxidant properties, but their mechanisms of action and structure-activity relations have not been fully investigated. We hypothesized that differences in antioxidant activity between the structurally similar flavones, luteolin and chrysin (differing only in B-ring hydroxylation patterns), would differentially affect inflammation-associated Cox-2 expression and PGE2 formation. Pretreatment of RAW 264.7 macrophage-like cells with 25, 50, or 100 micromol/L concentrations of luteolin inhibited lipopolysaccharide (LPS)-induced Cox-2 protein expression (P < 0.0001). Chrysin pretreatment did not reduce LPS-induced Cox-2 protein expression at any level tested. Conversely, both luteolin and chrysin completely suppressed LPS-induced PGE2 formation (P < 0.001). Luteolin, but not chrysin, inhibited xanthine/xanthine oxidase-generated superoxide formation at 100 micromol/L in a cell-free system (P < 0.001). Although both luteolin and chrysin reduced LPS-induced hydroxyl radical formation relative to the positive control (P < 0.001), luteolin was superior to chrysin (P = 0.003). In summary, luteolin and chrysin suppressed PGE2 formation equally well, despite differential effects on Cox-2 protein expression and on superoxide and hydroxyl radical scavenging. These data indicate that flavones may display similar antiinflammatory activity via different mechanisms.
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Affiliation(s)
- Gabriel K Harris
- United States Department of Agriculture, Diet and Human Performance Laboratory, MD 20705, USA.
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2038
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Katsoura MH, Polydera AC, Tsironis L, Tselepis AD, Stamatis H. Use of ionic liquids as media for the biocatalytic preparation of flavonoid derivatives with antioxidant potency. J Biotechnol 2006; 123:491-503. [PMID: 16457903 DOI: 10.1016/j.jbiotec.2005.12.022] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 11/11/2005] [Accepted: 12/15/2005] [Indexed: 11/23/2022]
Abstract
Biocatalytic preparation of acylated derivatives of flavonoid glycosides was performed using various immobilized lipases in two different ionic liquids, namely 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF(4)) and 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF(6)). The influence of various reaction parameters on the performance and the regioselectivity of the biocatalytic process was pointed out, using as model reaction the acylation of naringin and rutin with vinyl butyrate, catalyzed by immobilized Candida antarctica lipase at 60 degrees C. The biocatalytic modification of flavonoids strongly depended on the ionic liquid used, the molar ratio of substrates, as well as the acyl donor chain length. The highest conversion yield (about 65% after 96 h of incubation) was obtained with short chain acyl donors (up to four carbon atoms), at a relatively high molar ratio (10-15) in both ionic liquids used. The amount of monoacylated flavonoid derivatives produced in a single-step biocatalytic process in [bmim]BF(4) was up to 5.5 g/L for monoacylated rutin and 30 g/L for monoacylated naringin. The regioselectivity of the process was higher in [bmim]BF(4) than in [bmim]PF(6) or organic solvents. Reaction rates observed in ionic liquids were up to four times higher than those reported for organic media. The acylation of sugar moiety of rutin with various acyl donors affected its antioxidant potential towards both isolated LDL and total serum model in vitro. A significant increase of antioxidant activity was observed for rutin-4'''-O-oleate.
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Affiliation(s)
- M H Katsoura
- Laboratory of Biotechnology, Department of Biological Applications and Technologies, University of Ioannina, 45110 Ioannina, Greece
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2039
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Wangensteen H, Miron A, Alamgir M, Rajia S, Samuelsen AB, Malterud KE. Antioxidant and 15-lipoxygenase inhibitory activity of rotenoids, isoflavones and phenolic glycosides from Sarcolobus globosus. Fitoterapia 2006; 77:290-5. [PMID: 16701962 DOI: 10.1016/j.fitote.2006.03.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Accepted: 03/31/2006] [Indexed: 11/28/2022]
Abstract
From Sarcolobus globosus, two rotenoids (villosinol and 6-oxo-6a,12a-dehydrodeguelin), one isoflavone (genistin) and four phenolic glycosides (vanillic acid 4-O-beta-d-glucoside, glucosyringic acid, tachioside and isotachioside) were identified for the first time from this species. Extracts and compounds from S. globosus were evaluated for their DPPH radical scavenging and 15-lipoxygenase (15-LO) inhibitory activities. All tested rotenoids were found to inhibit 15-LO, while they lacked DPPH radical scavenging effect.
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Affiliation(s)
- Helle Wangensteen
- Division of Pharmacognosy, Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, P. O. Box 1068 Blindern, N 0316 Oslo, Norway.
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2040
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Pistelli L, Noccioli C, Martera M, Giamperi L, Bucchini A, Fraternale D, Ricci D. Antioxidant flavonol glycosides from Dorycnium hirsutum. Chem Nat Compd 2006. [DOI: 10.1007/s10600-006-0099-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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2041
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Cai YZ, Luo Q, Corke H. Structure–radical scavenging activity relationships of phenolic compounds from traditional Chinese medicinal plants. Life Sci 2006; 78:2872-88. [PMID: 16325868 DOI: 10.1016/j.lfs.2005.11.004] [Citation(s) in RCA: 514] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2005] [Accepted: 11/07/2005] [Indexed: 11/17/2022]
Abstract
Traditional Chinese medicinal plants associated with anticancer contain a wide variety of natural phenolic compounds with various structural features and possessing widely differing antioxidant activity. The structure-radical scavenging activity relationships of a large number of representative phenolic compounds (e.g., flavanols, flavonols, chalcones, flavones, flavanones, isoflavones, tannins, stilbenes, curcuminoids, phenolic acids, coumarins, lignans, and quinones) identified in the traditional Chinese medicinal plants were evaluated using the improved ABTS*+ and DPPH methods. Different categories of tested phenolics showed significant mean differences in radical scavenging activity. Tannins demonstrated the strongest activity, while most quinones, isoflavones, and lignans tested showed the weakest activity. This study confirmed that the number and position of hydroxyl groups and the related glycosylation and other substitutions largely determined radical scavenging activity of the tested phenolic compounds. The differences in radical scavenging activity were attributed to structural differences in hydroxylation, glycosylation and methoxylation. The ortho-dihydroxy groups were the most important structural feature of high activity for all tested phenolic compounds. Other structural features played a modified role in enhancing or reducing the activity. Within each class of phenolic compounds, the structure-activity relationship was elucidated and discussed. This study reveals the structure-activity relationships of a large series of representative natural phenolic compounds more systematically and fully than previous work. Structure-radical scavenging activity relationships of some natural phenolics identified in the medicinal plants were evaluated for the first time.
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Affiliation(s)
- Yi-Zhong Cai
- Department of Botany, The University of Hong Kong, Pokfulam Road, Hong Kong, PR China
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2042
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Chen W, Guo P, Song J, Cao W, Bian J. The ortho hydroxy-amino group: another choice for synthesizing novel antioxidants. Bioorg Med Chem Lett 2006; 16:3582-5. [PMID: 16621555 DOI: 10.1016/j.bmcl.2006.03.091] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Revised: 03/13/2006] [Accepted: 03/22/2006] [Indexed: 10/24/2022]
Abstract
Four ortho hydroxy-amino derivatives have been designed based on the structures of flavonoids to explore the effect of the ortho hydroxy-amino group on the antioxidant properties of molecules, and their bond dissociation enthalpies (BDE), ionization potentials (IP), the highest occupied molecular orbitals (HOMO), and spin densities have been calculated. The results reveal that the ortho hydroxy-amino group plays an important role in promoting the antioxidant properties of molecules because of its lowering effect on BDE, IP, and spin density. The derivatives with ortho hydroxy-amino group show stronger antioxidant activity than the derivatives with mono hydroxy or ortho dihydroxy group. Thus, the ortho hydroxy-amino group can be used as another potential functional group to synthesize novel antioxidants as guessed.
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Affiliation(s)
- Weijun Chen
- Department of Chemical Engineering, Northwest University, Xi'an 710069, China
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2043
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Antioxidant properties of some commonly consumed and underutilized tropical legumes. Eur Food Res Technol 2006. [DOI: 10.1007/s00217-006-0289-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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2044
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Bertrand A, Morel S, Lefoulon F, Rolland Y, Monsan P, Remaud-Simeon M. Leuconostoc mesenteroides glucansucrase synthesis of flavonoid glucosides by acceptor reactions in aqueous-organic solvents. Carbohydr Res 2006; 341:855-63. [PMID: 16530175 DOI: 10.1016/j.carres.2006.02.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 01/17/2006] [Accepted: 02/10/2006] [Indexed: 11/28/2022]
Abstract
The enzymatic glucosylation of luteolin was attempted using two glucansucrases: the dextransucrase from Leuconostoc mesenteroides NRRL B-512F and the alternansucrase from L. mesenteroides NRRL B-23192. Reactions were carried out in aqueous-organic solvents to improve luteolin solubility. A molar conversion of 44% was achieved after 24h of reaction catalysed by dextransucrase from L. mesenteroides NRRL B-512F in a mixture of acetate buffer (70%)/bis(2-methoxyethyl) ether (30%). Two products were characterised by nuclear magnetic resonance (NMR) spectroscopy: luteolin-3'-O-alpha-d-glucopyranoside and luteolin-4'-O-alpha-d-glucopyranoside. In the presence of alternansucrase from L. mesenteroides NRRL B-23192, three additional products were obtained with a luteolin conversion of 8%. Both enzymes were also able to glucosylate quercetin and myricetin with conversion of 4% and 49%, respectively.
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Affiliation(s)
- Anne Bertrand
- Laboratoire Biotechnologie-Bioprocédés UMR CNRS 5504, UMR INRA 792, INSA DGBA, 135 avenue de Rangueil, 31077 Toulouse Cedex 04, France
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2045
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Proestos C, Sereli D, Komaitis M. Determination of phenolic compounds in aromatic plants by RP-HPLC and GC-MS. Food Chem 2006. [DOI: 10.1016/j.foodchem.2004.12.016] [Citation(s) in RCA: 184] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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2046
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Kim JD, Liu L, Guo W, Meydani M. Chemical structure of flavonols in relation to modulation of angiogenesis and immune-endothelial cell adhesion. J Nutr Biochem 2006; 17:165-76. [PMID: 16169200 DOI: 10.1016/j.jnutbio.2005.06.006] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2005] [Revised: 06/15/2005] [Accepted: 06/17/2005] [Indexed: 11/28/2022]
Abstract
The antioxidant activity of flavonoids has been suggested to contribute to several health benefits associated with the consumption of fruits and vegetables. Four flavonols - myricetin (M), quercetin (Q), kaempferol (K) and galangin (G), all with different numbers of hydroxyl moieties (-OH) - were examined for their antioxidant activity and cytotoxicity on human umbilical vein endothelial cells (HUVECs) and for their potential antiangiogenic and cell adhesion effects. The relative antioxidant capacity of these flavonols in cell culture medium (cell-free system) and their intracellular antioxidant activity were M = Q > K = G, which correlated respectively with the presence of 3, 2, 1 and 0 moieties of -OH on their B-ring. The higher the numbers of -OH moieties on the B-ring the less toxic the flavonol was to HUVEC, and the LD50 was determined as: M (100 microM) > Q (50 microM) > K (20 microM) > G (10 microM). These flavonols at approximately 0.5 LD50 doses suppressed the vascular endothelial growth factor (VEGF)-stimulated HUVEC tubular structure formation by: M (47%) > Q (37%) > K (15%) > G (14%), which was not linearly associated with their numbers of -OH moieties. However, the magnitude of flavonols' suppression of activated U937 monocytic cells adhesion to HUVEC was associated with the number of -OH moieties on the B-ring. This was prominent when U937 cells were pretreated with these flavonols. In contrast, the numbers of -OH moiety had no apparent influence on the adhesion or expression of adhesion molecules when activated HUVECs were pretreated with these flavonols. The presence of different numbers of -OH moieties on the B-ring of the flavonols may contribute to their antioxidant activity as well as their toxicity and may play an important role in their potency for biological action such as angiogenesis and immune-endothelial cell adhesion, which, respectively, are important processes in the development of cancer and atherosclerosis.
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Affiliation(s)
- Jong-Deog Kim
- Department of Biotechnology, Yosu National University, Yosu, Cheonnam, 550-260 South Korea
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2047
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Evaluation of free radical-scavenging properties of commercial grape phenol extracts by a fast colorimetric method. Food Chem 2006. [DOI: 10.1016/j.foodchem.2004.12.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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2048
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Deschamps JD, Kenyon VA, Holman TR. Baicalein is a potent in vitro inhibitor against both reticulocyte 15-human and platelet 12-human lipoxygenases. Bioorg Med Chem 2006; 14:4295-301. [PMID: 16500106 DOI: 10.1016/j.bmc.2006.01.057] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2005] [Revised: 01/20/2006] [Accepted: 01/23/2006] [Indexed: 02/03/2023]
Abstract
Lipoxygenases (LO) have been implicated in asthma, immune disorders, and various cancers and as a consequence, there is great interest in isolating selective LO isozyme inhibitors. Currently, there is much use of baicalein as a selective human platelet 12-LO (12-hLO) inhibitor, however, our current steady-state inhibition data indicate that baicalein is not selective against 12-hLO versus human reticulocyte 15-LO-1 (15-hLO-1) (15/12=1.3), in vitro. However, in the presence of detergents baicalein is slightly more selective (15/12=7) as seen by the steady-state inhibition kinetics, which may imply greater selectivity in a cell-based assay but has yet to be proven. The mechanism of baicalein inhibition of 15-hLO-1 is reductive, which molecular modeling suggests is through direct binding of the catecholic moiety of baicalein to the iron. A structurally related flavonoid, apigenin, is not reductive, however, molecular modeling suggests a hydrogen bond with Thr591 may account for its inhibitor potency.
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Affiliation(s)
- Joshua D Deschamps
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA
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2049
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Molecular Dynamics Simulations on the Coplanarity of Quercetin Backbone for the Antioxidant Activity of Quercetin-3-monoglycoside. B KOREAN CHEM SOC 2006. [DOI: 10.5012/bkcs.2006.27.2.325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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2050
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Wang CZ, McEntee E, Wicks S, Wu JA, Yuan CS. Phytochemical and analytical studies of Panax notoginseng (Burk.) F.H. Chen. J Nat Med 2006. [DOI: 10.1007/s11418-005-0027-x] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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