• Journal of Ginseng Research
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• v.35 no.1
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• pp.60-68
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• 2011

The chemical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity changes of ginsenoside $Rb_1$-glycine and ginsenoside $Rg_1$-glycine mixtures by Maillard reaction were investigated to identify the role of Maillard reaction in the increased antioxidant activity of ginseng by heat-processing. The DPPH radical scavenging activity of $Rg_1$-glycine mixture was more strongly increased by heat-processing than that of $Rb_1$-glycine mixture. From the analyses of ginsenosides, $Rb_1$ was gradually changed into 20(S)-$Rg_3$, 20(R)-$Rg_3$, $Rk_1$ and $Rg_5$ by heat-processing. $Rg_1$ was gradually changed into 20(S)-$Rh_1$, 20(R)-$Rh_1$, $Rk_3$ and $Rh_4$ by heat-processing. However, the generation of these less-polar ginsenosides was not related to the increased DPPH radical scavenging activity of $Rb_1$-glycine and $Rg_1$-glycine mixtures because their DPPH radical scavenging activities were already significantly increased when dried at $50^{\circ}C$, which temperature induce no structural changes of ginsenosides. In the comparison of browning compound levels of $Rg_1$-glycine and $Rb_1$-glycine mixtures, the extents of Maillard reaction were positively correlated with their increased free radical scavenging activities. Based on the chemical and DPPH radical scavenging activity changes of $Rg_1$-glycine and $Rb_1$-glycine mixtures by heat-processing, we clearly identified that the increased free radical scavenging activity of ginsenoside is mediated by the Maillard reaction between sugar moiety of ginsenoside and amino acid.

• Food Science and Preservation
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• v.17 no.6
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• pp.867-873
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• 2010

The total phenolic contents and the antioxidant activities of methanolic extracts of different parts (fruit, calyx, leaf, stem, and root) of Physalis alkekengi var. francheti were investigated using established in vitro systems including DPPH radical-scavenging, nitrite-scavenging, superoxide anion radical-scavenging activity, measurement of reducing power, and assessment of the metal-chelating effect. The highest extraction yield was from fruit (52.55%), whereas the lowest levels were obtained from root (10.49%) and stem (12.88%).The leaf extract had the highest total phenolic (58.47 mg/g) and total flavonoid (4.83 mg/g) contents, plus the greatest antioxidant activity, as shown by the DPPH radical-scavenging assay, and the highest levels of reducing power at concentrations of 1 and 5 mg/mL. In addition, the calyx also showed good antioxidant activity.These findings indicate that methanolic extracts of leaf and calyx may be useful in the food manufacturing and nutraceutical industries.

• Natural Product Sciences
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• v.11 no.3
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• pp.150-154
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• 2005

The radical scavenging effect of the MeOH extract of Fraxini Cortex on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was examined. The $CH_2Cl_2$-and n-BuOH-soluble fractions of MeOH extract showed the promising DPPH radical scavenging effects, and further purified by silica gel, Sephadex LH-20 column chromatography, and reversed-phase C-18 MPLC to yield five coumarins, esculetin (1), fraxidin (2), fraxetin (3), fraxidin $8-O-{\beta}-D-glucopyranoside$ (fraxin methyl ether) (5), esculin (6), and a secoiridoid oleuropein (4), and a coumarin-secoiridoid escuside (7). Compounds 1, 3, and 4 showed potent DPPH radical scavenging effects, exhibiting $IC_{50}$ values of 14.68, 9.64, and $22.03\;{\mu}M$, respectively. Compounds 6 and 7 also showed moderate effects with $IC_{50}$ values of 147.79 and $72.73\;{\mu}M$, respectively. L-Ascorbic acid was used as a positive control and exhibited the $IC_{50}$ value of $50.31\;{\mu}M$.

• Journal of Korean Medicine for Obesity Research
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• v.9 no.2
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• pp.57-63
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• 2009

In recent year, We are concerned about anti-aging, disease-protection, long-life, many methods are used in solving this problem. And Those are related with antioxidative ability. Recently, We heard that Cucurbita moschata Duch. has anti-hypertensive effect and good for health. So I let made a experiment for this result of the anti-oxidant effect of Cucurbita moschata Duch. used for 3 methods, those are DPPH radical scavenging activity, Nitric oxide(NO) radical scavenging activity and Bovine serum albumin(BSA). The results of this study were as follows: We measured level of DPPH radical scavenging activity. And we obtained results that the ability of DPPH radical's elimination was increased when concentration of Cucurbita moschata Duch. was to $20\;mg/m{\ell}$. We measured level of Nitric oxide(NO) radical scavenging activity. And we founded that the ability of NO radical's elimination was increased when concentration of Cucurbita moschata Duch. was to $10\;mg/m{\ell}$. When we inspected antioxidation with Bovine serum albumin(BSA). And we obtained that antioxidative ability was increased after$2.5\;mg/m{\ell}$ of Cucurbita moschata Duch.. So I guess that Cucurbita moschata Duch. has effect of antioxidative ability. Hereafter we need differential experimental methods for evidence of antioxidative effect on Cucurbita moschata Duch.

• KSBB Journal
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• v.25 no.1
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• pp.55-61
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• 2010

To investigate antioxidant activity of the culture broth from submerged culture of Tremella fuciformis, we preferentially analyzed the chemical composition of culture broth, which was mainly composed of carbohydrate (296.39 mg/g) and protein (9.24 mg/g), respectively. Also, contents of polyphenols, flavonoids and flavonols were 16.63 mg/g, 9.19 mg/g and 83.74 ${\mu}/g$, respectively. Next, we examined the scavenging abilities on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical, ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) radical, the reducing power, and chelating ability on ferrous ions. All antioxidant activities of the culture broth were increased in proportion to its concentrations. The $IC_{50}$ values were in order as follows ABTS radical scavenging activity < OPPH radical scavenging activity < chelating power. Accordingly, these results suggest that pharmacological function of T. fuciformis might be due to, at least partially, their protective effects against oxidation and the culture broth of T. fuciformis was free radical inhibitors or scavengers at low concentration, involving possibly in termination of free radical reaction as primary antioxidants.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.312-316
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• 2009

Antioxidant-rich oils were extracted from different parts of sea buckthorn berry with supercritical $CO_2$ (SC-$CO_2$) and n-hexane. The functional components were analyzed and the extracts were screened for their potential as radical scavengers in 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), 2,2'-azinobis-3-ethylbenzotiazoline-6-sulphonic acid (ABTS), galvinoxyl systems. Minor differences were found in fatty acid composition of oils extracted by the two methods. Seed oil contains the highest content of tocopherols while pulp oil and whole berry oil possessed higher concentration of carotenoids. Whole berry oil, pulp oil, and seed oil extracted by SC-$CO_2$ showed 91.7, 90.9, and 93.5% radical scavenging activity (RSA) at 6 mg/mL towards DPPH and 74.3, 54.3, and 74.8% towards galvanoxyl radical at 10 mg/mL. The hexane-extracted oils showed similar scavenging ability. However, the oils obtained by hexane showed significantly higher RSA (p<0.05) than those obtained by SC-$CO_2$ while whole berry oil has the highest RSA towards ABTS among 3 oil samples.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.09a
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• pp.94-94
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• 2001

• Applied Biological Chemistry
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• v.46 no.1
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• pp.32-38
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• 2003

Seventy percent ethanolic extracts from commercially available 13 legumes were made to investigated their antioxidative activities by determining the reducing power, inhibitory effect on lipid peroxidation, scavenging activity against both superoxide radical and hydroxyl radical, together with inhibitory activity toward mitomycin C-induced oxidative damage of DNA. High level of reducing powers were detected in Yepat, Sokpiri, Yuweol-bean and Jeokdu. Inhibitory effects on lipid peroxidation were found ubiquitously in all extracts examined when employing the linoleic acid autoxidation system, whereas, only 3 legumes, Yepat, Namul-bean and Jeenuni-bean, were revealed marked inhibition in rabbit erythrocyte-ghost membrane lipid peroxidation system. Yepat, Namul-bean, Jeokdu and Jeenuni-bean showed great scavenging activities on superoxide radical, on the other hand, high level of hydroxyl radical scavenging activities were demonstrated in Sokpiri, Chungtae, Yepat and Jebi-bean. Ubiquitous inhibitory effects on mitomycin C-induced oxidative damage on DNA were found in all extracts tested, Among them, however, Yepat, Jeenuni-bean, Namul-bean, Nokdu and Jeokdu showed the higher level of inhibition. Taken together, we could assign Yepat, Jeokdu, Jeenuni-bean and Sokpiri, for the legume species highly functional on overall antioxidative activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.106-110
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• 2000

We investigated the active oxygen scavenging activity and active compound from Humulus japonicus. The ethyl acetate and butanol fraction exhibited strong scavenging effects on hydroxyl radical. Furthermore active compound was isolated and purified using Amberlite XAD-2 column chromatography and preparative HPLC from ethyl acetate fracton, and major compound was identified as a luteolin-7-O-$\beta$-D-glucoside by the MS, UV, 1H-NMR and 13C-NMR analyses. Luteolin-7-O-$\beta$-D-glucoside exhibited strong scavenging effect on active oxygens such as superoxide radical, hydroxyl radical and hydrogen peroxide.

• The Korea Journal of Herbology
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• v.24 no.4
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• pp.95-99
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• 2009

Objectives : This study were carried out to investigate the anti-oxidative activities of $\gamma$-SPE(gamma irradiated shell of Persicae semen extract with ethanol). Methods : Anti-oxidative was measured by DPPH free radical scavenging activities, nitric oxide radical scavenging activities, SOD-like activities, xanthine oxidase radical scavenging activities, nitrite scavenging activities and tyrosinase inhibition activities. Results : Effects of free radial scavenging was increased by irradiation. Tyrosinase inhibition activities was decreased by $\gamma$-SPE. Conclusions : Results suggested that $\gamma$-SPE have a potential as a new anti-oxidative material.