• Nutritional Sciences
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• v.9 no.1
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• pp.48-54
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• 2006

Methods have been developed to evaluate the total antioxidant capacity of foods and plasma but limitations are associated with their ability to determine precisely the contribution of lipophilic antioxidants in a lipid milieu as well as interactions among them Thus, we modified the Oxygen Radical Absorbance Capacity (ORAC) assay to determine the peroxyradical scavenging ability of both hydrophilic and lipophilic compartments in plasma The hydrophilic ORAC assay was performed in a phosphate buffer system utilizing 2,2'-azobis (2-amidinopropane) dihydrochloride as a peroxyradical generator and fluorescein as the target The lipophilic ORAC assay was carried out in a dimethylsulfoxide :butyronitrile (DMSO/BN, 9:1 v/v) system using 2,2'-azobis (2,4-dimethyl valeronitrile) as a peroxyradical generator and BODIPY C11 581/591 as the target Analyses were conducted in bovine serum supplemented with water - and lipid - soluble antioxidants and in human plasma. Albumin (0.5$\sim$5 g/dL) and uric acid (0.1$\sim$0.5 $\mu$mol/L) increased hydrophilic ORAC values in a dose-dependent fashion ($R^{2}$=0.97 and 0.98, respectively) but had no impact on lipophilic ORAC values. $\alpha$-Tocopherol (15$\sim$200 $\mu$mol/L) increased lipophilic ORAC values in a dose-dependent fashion ($R^{2}$=0.94); neither $\alpha$-tocopherol nor $\beta$-carotene had an impact on hydrophilic ORAC values. However, addition of $\beta$-carotene at physiological concentration (0.23$\sim$1.86 $\mu$mol/L), either alone or in combination with other carotenoids, had no significant impact on lipophilic ORAC values. Thus, while assays of 'total antioxidant capacity' in biological matrices would be a useful research and clinical tool, existing methods are limited by the lack of complete responsiveness to the full range of dietary antioxidants.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1505-1510
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• 2009

Arginyl-fructose (AF) and arginyl-fructosyl-glucose (AFG) were chemically synthesized and purified. Their in vitro and cellular antioxidant activity was investigated using oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity assay, respectively. The peroxyl radical scavenging activity of AF was much higher than that of AFG, which was in good agreement with their reduction capacity to donate electrons or hydrogen atoms. On the other hand, the hydroxyl radical scavenging activity of AF was weaker than that of AFG, which was consistent with their metal chelating activity, suggesting that AFG-$Cu^{2+}$ complex may be less redox-active than AF-$Cu^{2+}$ complex due to 1 glucose molecule attached. The cellular antioxidant activity of AF and AFG appeared to depend on both their permeability into cell membrane and the scavenging activity on peroxyl or hydroxyl radicals. These results indicate that AF and AFG, Maillard reaction products, may have a high potential as a material for the development of nutraceutical food with antioxidant activity.

• Natural Product Sciences
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• v.18 no.4
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• pp.261-265
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• 2012

Xanthohumol was isolated from hops (Humulus lupulus L.), and then investigated anti-oxidant effect by AAPH-induced LLC-PK1 cell and oxygen radical absorbance capacity (ORCA) assays and MMP-12 inhibitory effect by direct MMP-12 inhibition assay. The treatment of xanthohumol protected LLC-PK1 cells from AAPH-induced cell damage such as cell viability, SOD and GSH-px reduction in a dose dependant manner (0.1, 1, and $5{\mu}M$), the SOD value was 2.98, 4.51, and 5.77 U/mg protein, and GSH-px value was 30.12, 49.32, and 60.11 U/mg protein. ORAC value of xanthohumol was showed as 4320, 12004, and $14209{\mu}M$ TE/g at the concentration 0.1, 1, and $5{\mu}M$, respectively. The change of SOD and GSH-px values was significantly correlated with the results of ORAC assay, that is, AAPH-induced cell and ORCA assays. In addition, inhibition of MMP-12 that is known to play an important role in skin aging was 14%, 37%, 46%, and 79% at the concentration of 0.01, 0.1, 1, and $5{\mu}M$, respectively. On the basis of these results, xanthohumol from hops (Humulus lupulus L.) showed interesting biological and pharmacological activity such as anti-oxidant effect and anti-aging.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1053-1062
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• 2011

Reactive oxygen species (ROS), including singlet oxygen (${O_2}^1$), superoxide anion radical ($O_2{\cdot}^-$), hydroxyl radical ($HO{\cdot}$), peroxyl radical ($ROO{\cdot}$), hydrogen peroxide ($H_2O_2$), and hypochlorous (HOCl), are generated as byproducts of normal cellular metabolism. ROS induce damage to many biological molecules, such as lipids, proteins, carbohydrates, and DNA. It is widely believed that some degenerative diseases caused by ROS can be prevented by the high intake of fruits and vegetables due to their antioxidant activities. Recently, research on natural antioxidants has become increasingly active in various fields. Several assays have been developed to measure the total antioxidant capacity of antioxidants in fruits and vegetables in vitro. These assays include those for DPPH radical scavenging activity, SOD-like activity, total polyphenol content, oxygen radical absorbance capacity, reducing power, trolox equivalent antioxidant capacity (ABTS assay), single-cell gel electrophoresis (comet assay), and a cellular antioxidant activity assay. Because different antioxidant compounds may act through different mechanisms in vitro, no single assay can fully evaluate the total antioxidant capacity of foods. Due to the complexity of the composition of foods, it is important to be able to measure antioxidant activity using biologically relevant assays. In this review, recently used assays were selected for extended discussion, including a comparison of the advantages and disadvantages of each assay and their application to fruits and vegetables.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.393-401
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• 2007

This study was performed to investigate the antioxidant activity of Korean ginseng using an ORAC(Oxygen Radical Absorbance Capacity) assay. Four fractions each (80% ethanol, ethyl acetate, water saturated 1-butanol, and water) were obtained from different ginseng samples (White Ginseng: ; 6 yrs-., 5 yrs-., ; Cork Ginseng: ; 5 yrs-., 4 yrs-.). The saponin content of each fraction was quantified by LC/MS, and the antioxidant capacity of the ginseng was measured by the ORAC assay. The ORAC method, which was recently validated using automatic liquid handling systems, has been adapted for manual handling with the use of a conventional fluorescence microplate reader. Furthermore, the ORAC assay provides a direct measure of hydrophilic chain-breaking antioxidant capacity against peroxy radical, which is the exiting and emission of 2,2'-Azobis (2-methylpropionamidine)-dihychloride (AAPH). As a result of our experiments, ginsenosides Rg1 and Rb1 were the two major saponins found in the ginseng samples, and Rc, Rb2, Re, Rd, Rg3, and Rh1 were detected in a small quantities. For the antioxidant capacities of the fractions (80% ethanol, ethyl acetate, butanol, and water), we found that the organic solvent fraction had similar antioxidant capacities, and were higher than the capacity of the water fraction. When determining the similarities in each fraction, only the ethyl acetate fraction showed similarity compared to other fractions (p>0.05). The antioxidant capacity of ginseng may come from phenolic compounds and some nonpolar saponins. However, based on the results of this study, we hypothesize that some acidic polysaccharides and other biological components may contribute to its antioxidant capacity. Additional research is required to determine other possible biological response modifiers that contribute to the antioxidant capacity of ginseng.

• Natural Product Sciences
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• v.20 no.3
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• pp.176-181
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• 2014

The antioxidant activities of 29 components isolated from the aerial parts of Artemisia iwayomogi were evaluated in vitro and in cell culture. Among the tested compounds, 2, 6, 8, 10, 13, and 14 exhibited the greatest peroxyl radical-scavenging activities in the oxygen radical absorbance capacity (ORAC) assay, and 2, 10, and 14 also showed significant reducing capacities. However, all compounds showed weak metal chelating activities. Their cellular antioxidant activities were evaluated in HepG2 cells. At $10{\mu}M$, compounds 6, 8, and 14 exhibited stronger protection against 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress than compounds 2, 10, and 13. Moreover, Compounds 2 and 8 were more effective in protecting against $Cu^{2+}$-induced oxidative stress than compounds 6, 10, 13, and 14 at $10{\mu}M$. These results suggest that the phenolic compounds in A. iwayomogi have the potential to be developed as natural antioxidants for the treatment of oxidative stress-related diseases.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.17 no.3
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• pp.275-286
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• 2013

In the present study, antioxidant activity and protective effect of extracts from Sambucus williamsii var. coreana stems (SWC) were evaluated on tert-butyl hydroperoxide (t-BHP) induced oxidative stress in human liver (Chang) cells. Antioxidant activities of the SWC extracts were determined by various radical scavenging activities, such as DPPH, ferric reducing antioxidant power (FRAP), 2,2'-azinobis-(3-ethybenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and oxygen radical absorbance capacity (ORAC) assay. SWC extracts showed strong antioxidant effect on various assay. To determine the hepatoprotective effects of SWC on t-BHP induced oxidative damage, cell viability was measured using MTT assay. Pretreatment of SWC extracts showed increasing cell viability, decreasing ROS and restoring mitochondria membrane potential on t-BHP induced oxidative stress in Chang cells. Our findings suggest that SWC extracts may be considered a potential agent for therapeutic protective effect from oxidative stress through its antioxidant activity.

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.217-220
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• 2012

The fruits of Acanthopanax sessiliflorus Seeman (Araliaceae) were extracted with 70% aqueous ethanol at room temperature. The concentrated extract was partitioned with ethyl acetate (EtOAc), n-butyl alcohol, and $H_2O$, successively. From the EtOAc fraction, two compounds were isolated through the repeated silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies. According to the results of physicochemical and spectroscopic data including NMR, mass spectrometry, and infrared spectroscopy, the chemical structures of the compounds were determined as 3,5-dihydroxycinnamic acid (1) and protocatechuic acid (2). Compound 1 was isolated from the fruits of A. sessiliflirus Seeman for the first time. And the compounds were evaluated for the radical scavenging the antioxidant capacity using 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)diammonium salt, 1,1-diphenyl-2-picrylhydrazy, and oxygen radical absorbance capacity assay.

• Nutrition Research and Practice
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• v.11 no.1
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• pp.33-42
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• 2017

BACKGROUND/OBJECTIVE: This study aims to measure the in vitro antioxidant capacity of Korean diet (KD) with American diet (AD) as a control group and to examine the ex vivo DNA damage reduction effect on human lymphocytes. MATERIALS/METHODS: The KD applied in this study is the standard one-week meals for Koreans (2,000 kcal/day) suggested by 2010 Dietary Reference Intakes for Koreans. The AD, which is the control group, is a one-week menu (2,000 kcal/day) that consists of foods that Americans would commonly take in according to the National Health and Nutrition Examination Survey. The antioxidant capacity of each menu was measured by means of the total phenolic assay and 3 in vitro antioxidant activity assays (2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, trolox equivalent antioxidant capacity (TEAC), Oxygen radical absorbance capacity ($ORAC_{ROO{\cdot}}$)), while the extent of ex vivo lymphocyte DNA damage was measured by means of the comet assay. RESULTS: When measured by means of TEAC assay, the in vitro antioxidant capacity of the KD of the day was higher than that of the AD (P < 0.05) while there was no significant difference in total phenolic contents and DPPH and ORAC assays. The ex vivo lymphocyte DNA damage protective effect of the KD was significantly higher than that of the AD (P < 0.01). As for the one-week menu combining the menus for 7 days, the total phenolic assay (P < 0.05) and in vitro antioxidant capacity (P < 0.001, DPPH; P < 0.01, TEAC) of the KD menu were significantly higher than those of the AD menu. Likewise, the ex vivo DNA damage reduction rate of the Korean seven-day menu was significantly higher than that of the American menu (P < 0.01). CONCLUSION: This study demonstrates that the high antioxidant capacity and DNA damage protective effect of KD, which consists generally of various plant foods, are higher than those of typical AD.

• Korean Journal of Pharmacognosy
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• v.46 no.4
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• pp.303-308
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• 2015

Ten phenolic compounds were isolated from the twigs of Stewartia pseudocamellia. The isolated compounds were identified as 5,7,3',5'-tetrahydroxyflavanone (1), 3,5,7,3',5'-pentahydroxyflavanone (2), quercetin (3), (+)-aromadendrin (4), (+)-ampelopsin (5), myricetin (6), (+)-catechin (7), (-)-epicatechin (8), kaempferol (9), and fraxin (10) by spectroscopic analysis. Compounds 1, 2, 4, 6, 8, and 9 were isolated from this plant for the first time. The antioxidant activities of compounds 1-10 were evaluated by the DPPH and/or ORAC (oxygen radical absorbance capacity) assay. Compounds 3, 5-9 showed significant antioxidative effects on DPPH assay. Among the active compounds, 6 exhibited higher activity compared to trolox on ORAC assay.