• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.157-163
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• 2002

An investigation was carried out to study the characteristics of lipoxygenase in dioctyl sulfosuccinate (aerosol-OT, AOT)/isooctane revered micelles of microaqueous system containing infinitesimal water. ${\alpha}-Linoleic$ acid as a substrate could be analyzed by the colorimetric methodology using 5%(w/v) cupric acetate-pyridine solution and the activity of lipoxygenase was able to be assayed by the degree of ${\alpha}-linoleic$ acid consumption per minute. Optimal pH, temperature, and R-value ([water]/[AOT]) were determined as the value of 5.0, $25^{\circ}C$, and 10.0, respectively. Kinetic analysis of the enzyme reaction under the optimal conditions showed that the values of $K_m$ and $V_{max}$ were 0.31 mM of ${\alpha}-linoleic$ acid and $384.16{\mu}mol$ of ${\alpha}-linoleic$ acid decomposed/min, respectively. The results indicate the reaction to be lipoxygenase-catalyzed oxidation of ${\alpha}-linoleic$ acid in AOT/isooctane reversed micellar system. The inhibitory effect of natural antioxidants on lipoxygenase showed little inhibitory effect of L-ascrobic acid while ${\alpha}-tocopherol$ showed 72% of inhibitory effect.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.37-41
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• 1992

Starch solid system was used to investigate the effects of lipoxygenase, linoleic acid and water activity on the oxidation of ${\beta}-carotene$ or ${\alpha}-tocopherol$. ${\beta}-carotene$ or ${\alpha}-tocopherol$ was co-oxidized severely with linoleic acid by lipoxygenase, and these were reduced to 19% and 5% of initial concentration, respectively, after 2 days storage at $a_w$ 0.72 in the system. The concentration of ${\beta}-carotene$ and the destruction rates were linearly correlated. However, the ${\beta}-carotene$ was very stable in the system without linoleic acid and lipoxygenase. The oxidation products of ${\alpha}-tocopherol$ were considered as ${\alpha}-tocopheryl$ quinone and ${\alpha}-tocopheryl$ dimer, and the level of ${\alpha}-tocopherol$ quinone increased as the reaction time increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.280-285
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• 1993

The bioactivity of garlic extract was evaluated, based on the inhibition of soybean lipoxygenase. While the inhibition of lipoxygenase by the chloroform extract (1$_{50}$ value after 10min precirculation, 55mg/$m\ell$) of garlic homogenate shows the property as irreversible inhibitors, the aqueous extract (1$_{50}$ value, 65mg/$m\ell$) appeared to contain mainly reversible inhibitors. In the related study, diallyldislufide and dimethyldisulfide inhibited the enzyme with 1$_{50}$ value of 1.3mM and 18mM, respectively. These disulfides demonstrated both irreversible and reversible patterns of inhibition. In addition, synthetic alliin(allylcysteine sulfoxide) was found to inhibit the enzyme at high concentration (approximately 22%, at 10mM), and its decomposition products showed the irreversible property in the inhibition, in contrast to S-ethyl cysteine sulfoxide which expressed no significant inhibition. Thus, it is suggested that the garlic macerate contains both irreversible and reversible sulfur inhibitors.itors.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.223-227
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• 2005

Anti-inflammatory assay was conducted on 20 kinds of traditional Indonesian medicinal herbs using soybean lipoxygenase (SLO) and hyaluronidase (HAse). Cinnamomun burmanni Bl showed highest anti-inflammatory activity. Ethyl acetate fraction from methanol extract of C. burmanni Bl bark showing high SLO inhibitory activity was isolated using silica gel-60 column chromatography. Two compounds were isolated and purified through preparative HPLC. Through analyses of UV, $^1H-NMR$, $^{13}C-NMR$, EI-MS and $FAB^+-MS$, compounds 1 and 2 were identified as coumarin and 2-hydroxy cinnamaldehyde, respectively, among which 2-hydroxy cinnamaldehyde showed SLO inhibitory activity of $IC_{50}\;=\;60\;{\mu}M$. Both compounds did not exhibit HAse inhibitory activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.979-984
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• 2008

The stems of P etasites japonicus were extracted with ethanol and then partitioned with hexane, chloroform, ethyl acetate, n-butanol and water, successively. The antioxidant potency of five crude fractions were determined using (1) 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, (2) thiobarbituric acid reactive substances (TBARS) assay in the linoleic acid model system, and (3) lipoxygenase inhibition assay. Among the crude fractions, the ethyl acetate fraction exhibited the most potent antioxidant effect. By activity-guided fractionation, compound PJ-4 was isolated from the ethyl acetate fraction through the repeated silica gel open column chromatography. The chemical structure of the isolated compound was determined as kaempferol by $^1H-$ and $^{13}C$-NMR analysis and its antioxidative capacity was further investigated. DPPH radical scavenging activity of the compound was 65.76% at the concentration of $100 \;{\mu}g/mL$. The inhibitory activity of the compound against lipid peroxidation and lipoxygenase exhibited 43.47% and 58.60%, respectively at the concentration of $100\;{\mu}g/mL$. The result suggests that the compound may serve as a useful natural antioxidant and furthermore indicates the possibility of developing the stems of Petasites japonicus as a natural antioxidant source.

• Journal of Life Science
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• v.26 no.9
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• pp.1022-1026
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• 2016

In this study the hot water extract was prepared from Hydrocotyle sibthorpioides (Araliaceae) leaves and stems to study antioxidant activities and lipoxygenase inhibition. The extract showed the protective hydroxyl radical (-OH) which can damage virtually all types of macromolecules: carbohydrates, nucleic acids (mutations), lipids (lipid peroxidation), and amino acids. Hydroxyl radical scavenging activity of H. sibthorpioides was 78.6%. The extract showed strong activity against 1, 1- diphenyl 2-picrylhyorazyl (DPPH) which is a well-known radical and a trap (scavenger) for other radicals. DPPH scavenging activity of leaves of H. sibthorpioides was evaluated at 8.0 mg/ml was 86.0%. Lipoxygenases (LOXs) constitute a heterogeneous family of lipid peroxidizing enzymes capable of oxygenating polyunsaturated fatty acids to their corresponding hydroperoxy derivatives. The inhibitory effect of 15-LOX by H. sibthorpioides was assayed using a Morgan microplate assay. The extract of H. sibthorpioides was 55.5% inhibitory effects on the inhibition of LOX at 8.0 mg/ml. The IC₅₀ values for OH activity, DPPH activity, and LOX inhibition from leaves 5.23 mg/ml, 6.44 mg/ml, and 3.71 mg/ml, respectively. Antioxidative activity assay showed that the water extracts from leaf and stem had a strong reducing power. These results show that H. sibthorpioides has some phytochemical constituents which may be active against the free radicals (OH and DPPH) and lipoxygenase enzyme.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.959-963
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• 1994

To detect bioactive compounds present in unused marine resources, the screening for the 5-lipoxygenase inhitors in Asterina pectinifera, Halocynthia roretzi skin, Nototodarus sloani ink, Anthocidaris crassispina skin, SArgassum horneri, Agarum cribrosum, Odonthalia corymbifera and Desmarestia ligulata was carried out. THe ether and acetone extracts of Sargassum horneri had the strongest antioxygnic activityon lipid oxidation by potato lipoxygenase-1 (one of 5-lipoygenase) among the tested marine samples and their $IC_{50}$ were 0.3 and 1.1g/ml, respectively. The ether and acetone extracts of Asterina pectinifera, the acetone extracts of Halocynthia roretizi, and the acetone extracts of Nototodarus sloani ink had strong inhibitory activity and their $IC_{50}$ were 72.5, 65, 13.3 and $13.3\mu\textrm{g}/ml$, respectively. In addition, the $IC_{50}$ of the acetone extracts of Agarum cribrosum and Desmarestia ligulata, and the ether extracts of Desmarestia ligulata were 15.5, 35 and $30.5\mu\textrm{g}/ml$, respectively. The nonpolar solvent (ether, acetone) extracts of tested marine organism had more antioxigenic effect against 5-lipoxygenase than the polar solvent(water) extracts.

• Journal of Integrative Natural Science
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• v.4 no.3
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• pp.210-215
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• 2011

Holographic quantitative structure-activity relationships (HQSAR) is a useful tool to correlates structures with their biological activities. HQSAR is a two dimensional (2D) QSAR methodology, which generates QSAR equations through 2D fingerprint and correlates it with biological activity. Here, we report a 2D-QSAR model for a series of fifty-one 3,4-dihydroxychalcones derivatives utilizing HQSAR methodology. We developed HQSAR model with 6 optimum numbers of components (ONC), which resulted in cross-validated correlation coefficient ($q^2$) of 0.855 with 0.283 standard error of estimate (SEE). The non-cross-validated correlation coefficient (r2) with 0.966 indicates the model is predictive enough for analysis. Developed HQSAR model was binned in to a hologram length of 257. Atomic contribution map revealed the importance of dihydroxy substitution on phenyl ring.

• Journal of Ginseng Research
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• v.20 no.1
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• pp.1-6
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• 1996

Effects of Panax ginseng on allergic reactions were studied uslng various in vivo and in vitro experimental models such as 48-hr passive cutaneous anaphylaxis, mediators-induced skin reactions, histamine release from rat peritoneal mast cells, hexosaminidase release from RBL-2H3 cells, and lipoxygenase assay . In all of anti-allergic experiments we conducted, ginseng components (50% ethanol extract or ginseng total saponin or ginsenosides) extracted from Korean red ginseng, did not show significant anti-allergic actions. In 48-hr passive cutaneous anaphylaxis and mediators-induced skin reactions, 50% ethanol extract did not suppress hypersensitivity reactions. Total saponin, 50% ethanol extract, and 8 major ginsenosides did not show inhibitory effects on lipoxygeanse activity. Ginseng total saponin did not inhibit histamine release from rat peritoneal mast cells. All of the ginseng components mentioned above were also tested on RBL-2H3 cells, but none of them inhibited hexosaminidase release from this cell line. These results suggest that Panax ginseng does not have effects on allergic reactions at the level of 50% ethanol extract or total saponin used. All of 8 major saponin components tested ($Rb_1$, $Rb_2$, Rc, Rd, Re, Rf, $Rg_1$, $Rg_2$), did not inhibit lipoxygenase activity and degranulation events.

• YAKHAK HOEJI
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• v.33 no.6
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• pp.319-323
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• 1989

Polymorphonuclear leukocyte (PMNL) was obtained from peritoneal cavity in rat treated with casein. Effects of divalent cations and drugs on leukotriene $B_4(LTB_4)$ formation from arachidonic acid in the PMNL were determined by HPLC assay. 5-Lipoxygenase, a key enzyme for $LTB_4$ formation from arachidonic acid, exhibited $V_{max}$ at $1\;{\times}\;10^{-5}M$, and $K_m$ at $9.89\;{\times}\;10^{-5}M$ of arachidonic acid. Optimal $Ca^{++}$ concentration for the enzyme activity was $1\;{\times}\;10^{-5}M$ but $Zn^{++}$ did not show any significant effects on the $LTB_4$ formation. Indomethacin and caffeic acid exhibited inhibitory effects on the $LTB_4$ formation at $1\;{\times}\;10^{-5}M$ and $4\;{\times}\;10^{-5}M$, respectively. However, 6-aminohexanoic acid did not show any significant effects on the $LTB_4$ formation.