• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.893-897
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• 2002

The chloroform layer from 75% ethanol extract of Dalbergia odorifera T.CHEN showed strong antioxidative activity on lard and palm oil as tested by Rancimat method. Antioxidative active compound isolated and identified by silica gel column chromatography, thin layer chromatography, mass spectrophotometer, $^1H-NMR$ and $^{13}C-NMR$ was identified as mucronulatol (3(R&S)-3,7-Dihydroxy-2',4-dimethoxyisoflavan). Results of Rancimat method revealed the induction period of Mucronulatol increased longer than those of synthetic antioxidant, BHA and BHT, at the same concentration. Mucronulatol combined with ${\delta}-tocopherol(200ppm)$, and with ascorbic acid (200 ppm) and citric acid (200 ppm) on lard and palm oil, respectively, showed strong synergistic effects.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.1
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• pp.100-106
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• 1999

The antioxidative effect of leaves of Cedrela sinensis on 0.1M-linoleic acid was compared with some commercial antioxidants during storage at 50$\pm$2$^{\circ}C$ for 20 hours, and on soybean oils at 60$\pm$2$^{\circ}C$ for 30days. In the oxidation of linoleic acid, antioxidative effects of various leaves of Cedrela sinensis extracts and other antioxidants were shown in the following orders: 3% leave of Cedrela sinensis methanol extract＞1% leave of Cedrela sinensis methanol extract＞0.02% BHT＞3% leave of Cedrela sinensis ethyl acetate extract＞0.5% leave of Cedrela sinensis methanol extract＞0.02% tocopherol＞leave of Cedrela sinensis methanol extract 0.1, 0.02%＞leave of Cedrela sinensis ethyl acetate extract 1, 0.5, 0.1, 0.02%＞control, while in the oxidation of soybean oil, 1% leave of Cedrela sinengis methanol extract＞0.02% BHT＞3% leave of Cedrela sinengis methanol extract＞0.02% tocopherol＞control. The relative antioxidant effectiveness (RAE) were shown to be available in all substrates and the best effect was shown in substrate added compound of 3% leave of Cedrela sinensis methanol extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.750-754
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• 2005

The antioxidative capacity of methanol extracts prepared from jujubes (Zizyphus jujuba) were investigated by measuring total phenolic compounds, electron donating ability and induction period on lard. The extracts of large, medium and small jujubes of $80\%$ methanol extracts (methanol extracts) and soaking in the water before $80\%$ methanol extracts (water-methanol extracts) were Iyophilized. Total phenolic compounds of small, medium and large jujube of methanol extracts were 326.46 mg$\%,223.13\\;mg\%,\;158.06\;mg\%$ and that of water-methanol extracts were $113.23\;mg\%,\;81.45\;mg\%,\;72.78\;mg\%$, respectively. The Electron donating ability for the water-methanol extracts added samples of large (1.5$\~$3.0$\%$), medium and small jujube $(1.0\~3.0\%)$ were superior to the $0.02\%$ BHT added sample. On the induction period, all samples with jujube extracts were exhibited higher Antioxidant Index (AI: Induction period of lard with jujube extracts divided by induction period of lard) than that of the control and the water-methanol extracts were more effective than the methanol extracts on the antioxidative capacity for the lard. This result indicated that two lyophilized extracts of jujubes showed excellent free radical scavenging ability and long induction period on lard.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.408-416
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• 2020

This study examined the neuronal cytotoxicity of aluminum chloride (AlCl3), a dementia inducer, and the protective effects of Aster yomena (Kitam.)(AY) extract on AlCl3-induced cytotoxicity in cultured C6 glioma cells. The antioxidative effects, such as the inhibitory ability of xanthine oxidase (XO) and superoxide anion-radical (SAR) scavenging ability, on cell viability were examined. AlCl3 decreased the cell viability significantly in a dose-dependent manner, and the XTT50 value was 130.0 μM in these cultures. The cytotoxicity of AlCl3 was determined to be mid-toxic according to the Borenfreund and Puerner' toxic criteria. Quercetin (QU), an antioxidant, increased the cell viability reduced by AlCl3-induced cytotoxicity. The protective effect of the AY extract on AlCl3-induced cytotoxicity was analyzed. The AY extract increased the cell viability remarkably compared to the AlCl3-treated group and showed the inhibitory ability of XO and SAR-scavenging ability. The cytotoxicity of AlCl3 was correlated with oxidative stress, and the AY extract effectively prevented AlCl3-induced cytotoxicity through its antioxidative effects. In conclusion, natural resources, such as the AY extract, may be a putative agent for improving the cytotoxicity of heavy metallic compounds correlated with oxidative stress, such as AlCl3, a morbid agent.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.191-196
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• 2010

In the course of screening for antioxidant compounds by measuring the radical scavenging effect on 1,1-diphenyl- 2-picrylhydrazyl (DPPH), a total extract of the twigs of Stewartia koreana (Theaceae) was found to show potent antioxidant activity. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of six phenolic compounds, ampelopsin (1), catechin (2), proanthocyanidin-A2 (3), fraxin (4), (2R, 3R)-taxifolin-3-${\beta}$-D-glucopyranoside (5), and (2S, 3S)-taxifolin-3-${\beta}$-D-glucopyranoside (6), as active principles. Their structures were elucidated by spectroscopic studies. Compounds 1-6 were isolated for the first time from this plant. Among them, three compounds 1-3 showed the significant antioxidative effects on DPPH, and riboflavin originated superoxide quenching activity. In riboflavin-nitrobluetetrazolium (NBT)-light system, compound 1 showed better superoxide quenching activity than vitamin C.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.346-347
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• 2011

• Natural Product Sciences
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• v.17 no.4
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• pp.261-266
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• 2011

During the process of screening for antioxidative effects of natural plants in Korea, by measuring the superoxide quenching activity, methanol extract of the whole plant, Galium verum var. asiaticum (Rubiaceae), was found to show potent antioxidant activity. Subsequent activity-guided fractionation of methanol extract of Galium verum var. asiaticum led to the isolation of five phenolic compounds. Using spectroscopic techniques, the chemical structures were elucidated as: caffeic acid (1), narcissin (2), rutin (3), luteolin-7-O-${\alpha}$-L-rhamnopyranosyl (1 ${\rightarrow}$ 2)-${\beta}$-D-glucopyranoside (4), and luteolin-7-O-${\beta}$-D-glucopyranoside (5). These compounds were isolated for the first time from this plant. Among them, compound 1 showed the most significant riboflavin-originated superoxide and xanthine-originated superoxide quenching activities. Compounds 3 and 4 exhibited mild superoxide quenching effects compared with vitamine C.

• Ocean and Polar Research
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• v.39 no.1
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• pp.45-49
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• 2017

During the search for anticholinesterase compounds from marine organisms, we were able to isolate 6,6'-bieckol from a red alga, Grateloupia elliptica. This compound showed moderate acetylcholinesterase (AChE) inhibitory activity in a micromole range ($IC_{50}$ $44.5{\mu}M$). However, for butyrylcholinesterase (BuChE), a new target for the treatment of Alzheimer's disease (AD), it showed particularly potent inhibitory activity ($IC_{50}$ $27.4{\mu}M$), which is more potent compared to AChE. It also inhibits BACE-1, a new target for reducing the generation of ${\beta}-amyloid$.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.273-277
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• 1998

In order to determine the structure-activity relationships for antioxidative effects of gagaminine, a steroidal alkaloid isolated from the roots of Cynanchum wilfordi (Asclepiadaceae), two derivatives identified as sarcostin and penupogenin were prepared from gagaminine by hydrolysis and reduction. These compounds were evaluated for the inhibitory effects on the aidehyde oxidase activity and on lipid perbxidation in vitro. Furthermore, their effects were compared with those of gagaminine and the related compounds, cinnamic acid and nicotinic acid. The results of this study prove that the cinnamoyl group in the structure of gagaminine is critical in inhibition of the aldehyde oxidase activity while the nicotinoyl group may be necessary for anti-lipid peroxidation of the compound.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.184-189
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• 2011

Polysaccharide (PS) was fractionated from hot-water extract of Artemisia iwayomogi Kitamura stems. PS showed considerably higher hydroxyl radical scavenging activity than caffeic acid and glutathione. PS showed lower superoxide anion radical scavenging activity than hydroquinone and ascorbic acid. The scavenging activity of PS on the reactive oxygen species (ROS) induced by human neutrophils with zymosan was determined by the lucigenin-enhanced chemiluminescence assay. The scavenging effect of the PS on ROS as determined by the chemiluminescence assay was about 2-fold stronger than that of ascorbic acid at the same concentration. PS significantly decreased protein carbonyl and malonaldehyde contents in UVB irradiated skin homogenates, which was comparable to glutathione at the same concentration. This result suggested that PS derived from A. iwayomogi Kitamura stems may be a potent candidate as functional compound for the protection on UVB induced skin damage in cosmetics.