• Korean Journal of Pharmacognosy
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• v.47 no.4
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• pp.301-306
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• 2016

Four phenylpropanoid glycosides and a monoterpene glycoside were isolated from the flower of Clerodendrum trichotomum. Structures of the isolated compounds were identified as acteoside (1), martynoside (2), leucosceptoside A (3), isoacteoside (4) and neohancoside A (5) by spectroscopic analysis. Compounds 1-4 were isolated from the flower of C. trichotomum for the first time. Compound 5 was first obtained from genus Clerodendrum as well as family Verbenaceae. The antioxidant activity of compounds 1-5 were evaluated by the DPPH free radical scavenging assay. Compounds 1-4 exhibited strong antioxidant activity.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1619-1624
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• 2014

A new series of carbazole based 2,4-disubstituted thiazole derivatives were synthesized. All the synthesized compounds were tested for their cytotoxicity against three different cancer cell lines A549, MCF-7, and HT29. Some of these compounds showed good cytotoxicity. These compounds were also evaluated for antioxidant activity. Compounds 3a, 3b, 3d-f and 3i showed higher antioxidant activity than standard BHT.

• Natural Product Sciences
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• v.14 no.4
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• pp.227-232
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• 2008

Phytochemical further investigation of the chloroform extract of the aerial parts of Crucianella maritima L. (Rubiaceae) growing in Egypt resulted in the isolation of a new anthraquinone; 3-formyl-1-hydroxy-2-methoxy anthraquinone (3) along with the four known compounds isolated for the first time from the genus Crucianella; alizarin-1-methyl ether (2), 1,4-dihydroxy-2-methoxy anthraquinone (5), 1, 3, 6-trihydroxy-2-methoxy anthraquinone (7) and the flavonol kaempferol (8), beside four known compounds previously isolated from the same plant. The structures of the isolated compounds were established based on different spectroscopic data including UV, IR, EIMS, 1D and 2D-NMR. Moreover, the antioxidant and antimicrobial activities of the isolated compounds were evaluated.

• Natural Product Sciences
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• v.11 no.3
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• pp.174-178
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• 2005

Oxidative stress is an important causative factor in several human chronic diseases, such as atherosclerosis, cardiovascular disorders, mutagenesis, cancer, several neurodegenerative disorders, and the aging process. Phenolics and tannins are reported to be good antioxidants. Anogeissus latifolia (Combretaceae) bark has been used in the Indian traditional systems of medicine for curing a variety of ailments, but scientific validation is not available till date. Hence the present study was undertaken to isolate antioxidant compounds by activity-guided isolation. Inhibtion of diphenyl picryl hydrazyl (DPPH) and Xanthine oxidase along with photochemiluminescence assay were used as bioassay for antioxidant activity. Activity guided isolation was carried out using silica column and the compounds were quantified using HPLC. Ethyl acetate and butanol fraction exhibited potent antioxidant activity. Bioassay-guided isolation led to isolation of ellagic acid (1) and dimethyl ellagic acid (2) as the main active compounds, which along with gallic acid were quantified by HPLC. Thus we conclude that these three major tannoid principles present in A. latifolia, are responsible for the antioxidant potential and possibly their therapeutic potential.

• Ocean and Polar Research
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• v.33 no.3
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• pp.255-263
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• 2011

The aim of this investigation was to evaluate antioxidant activity of crude extracts from the halophyte Vitex rotundifolia, their solvent fractions, and isolated compounds (1-3). Antioxidant capacity was determined by measuring DPPH radical, and authentic $ONOO^-$ and $ONOO^-$ generated from 3- morpholinsydnonimine (SIN-1) in vitro as well as degree of occurrence of intracellular ROS, NO and GSH in mouse macrophage Raw 264.7 cells. From comparative analysis, MeOH extract, n-BuOH, and 85% aq. MeOH solvent fractions showed significant antioxidant effect in DPPH radical and $ONOO^-$ assay systems. Activity-guided purification of n-BuOH and 85% aq. MeOH fractions led to the isolation of flavonoids 1-3. Among them, compound 1 exhibited excellent antioxidant effect in all bioassay systems tested. On the other hand, compounds 2 and 3 revealed potent inhibitory effect against $ONOO^-$ generated from SIN-1, comparable with the positive control penicillamine.

• Preventive Nutrition and Food Science
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• v.19 no.2
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• pp.108-114
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• 2014

Four Korean kernel fruit (apple, pear, persimmon, and mandarin orange) juices were obtained by household processing techniques (i.e., blending, juicing). Whole and flesh fractions of each fruit were extracted by a blender or a juicer and then examined for phytochemical content (i.e., organic acids, polyphenol compounds). The antioxidant capacity of each juice was determined by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Results revealed that juices that had been prepared by blending whole fruits had stronger antioxidant activities and contained larger amounts of phenolic compounds than juices that had been prepared by juicing the flesh fraction of the fruit. However, the concentration of ascorbic acid in apple, pear, and mandarin orange juices was significantly (P<0.05) higher in juice that had been processed by juicing, rather than blending. The juices with the highest ascorbic acid (233.9 mg/serving), total polyphenols (862.3 mg gallic acid equivalents/serving), and flavonoids (295.1 mg quercetin equivalents/serving) concentrations were blended persimmon juice, blended mandarin orange juice, and juiced apple juice, respectively. These results indicate that juice extraction techniques significantly (P<0.05) influences the phytochemical levels and antioxidant capacity of fruit juices.

• KSBB Journal
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• v.23 no.1
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• pp.96-100
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• 2008

In this work, we describes analysis of the antioxidant potential of Korean green tea phenolics using an high-performance liquid chromatography (HPLC) on-line $ABTS^{+}$ antioxidant screening method. In conjunction with the analysis of their 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) radical scavenging ability, the extraction of catechine compounds from Korean green tea were performed by various temperature and time. The optimum operating conditions were experimentally determined to analyze the catechine compounds in the pretreatment extracts. From the results, the extraction temperature $60^{\circ}C$, time 3 min was selected as an optimal antioxidant activity condition. The analysis by $C_{18}$ column was performed, the flow rate of mobile phase and UV wavelength was fixed at 1.0 ml/min and 254 nm, respectively. the mobile phase was composed from acetonitrile and water, and the gradient elution mode were applied.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.728-734
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• 2006

The tannins represent a highly heterogeneous group of water-soluble plant polyphenols that may play an important role in antimutagenic and antioxidant properties. We investigated the antioxidant function of tannic acid in comparison to other phenolic compounds including catechin, chlorogenic acid, cinnamic acid, ellagic acid, and gallic acid for their ability to scavenge several stable radicals and reactive oxygen species (ROS) such as ${\bullet}DPPH^+$, ${\bullet}ABTS^+$, hydrogen peroxide, hydroxyl radical, and superoxide radical. The ability of tannic acid to decrease paraquat-induced lipid oxidation in mouse liver and lung through its antioxidant properties was also assessed. The results showed that almost all the tested compounds have stable radical scavenging activity except cinnamic acid. Tannic acid, gallic acid, and ellagic acid demonstrated remarkable ROS scavenging properties toward $H_2O_2$, ${\bullet}OH^-$, ${\bullet}O_2^-$ and especially only tannic acid could inhibit paraquat-induced lipid peroxidation effectively in mouse liver and lung. Based on these results, it appears that increased number of galloyl and ortho-hydroxyl groups enhances the antioxidant activity of phenolic compounds and tannic acid is evaluated as the most effective antioxidant among all the tested compounds. These results suggest that the tannins, especially tannic acid, can be used as therapeutic agent for various diseases caused by ROS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.2
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• pp.188-194
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• 2009

Antioxidant compounds and activities of raw and cooked (blanching, pan-frying, soy sauce pickle, Kochugang pickle) domestic garlic stems were investigated. The contents of chlorophyll, carotenoid, vitamin C, phenolic compounds and allicin in raw and cooked garlic stems were measured. Various cooking process increased significantly chlorophyll and $\beta$-carotene contents of garlic stem, but decreased vitamin C, phenolic compounds and allicin contents (p<0.05). Antioxidant activities of methanol extracts from raw and cooked garlic stem such as electronic donating ability (EDA), superoxide dismutase (SOD)-like activity and nitrite scavenging ability (NSA) were compared. The antioxidant activities were found to have lowered in the order of raw> pan-frying> blanching> garlic stem soy sauce pickle> garlic stem Kochujang pickle. Antioxidant activities of cooked garlic stems were more than 65% of cooked garlic bulbs.

• Journal of Applied Biological Chemistry
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• v.62 no.2
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• pp.195-202
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• 2019

Rhus javanica L. is Anacardiaceae plant distributed in East Asia. We evaluated the antioxidant activity and antiinflammatory effect of leaf, branch, root of ethyl acetate fraction from R. javanica. To confirm effective each extraction, The antioxidant activity was evaluated using 1,1-Diphenyl-2-picryl-hydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity assays, and the anti-inflammatory activity was evaluated based on inhibitory activities on the protein and mRNA expression of iNOS and COX-2 in LPS-induced RAW264.7 cells. The phenolic compounds content of each extract was analyzed with Folin reagents and HPLC/PDA method. The gallic acids were identified and quantified. The roots of R. javanica showed strong antioxidant activity. Its total phenolic compounds content were higher than the orders. In addition, anti-inflammatory activity inhibited the protein and mRNA expression of nitric oxide production factor, following the same pattern as contents of phenolic compounds included gallic acid and its antioxidant activity. In conclusion, R. javanica showed effective antioxidant and anti-inflammatory activity. Especially, the roots were evaluated to be highly valuable as a natural resource for reducing inflammation.