• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.171-181
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• 2006

Objectives : Peroxynitrite($ONOO^-$), superoxide anion(${\cdot}{O_2}^-$) and nitric oxide (NO) is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been implicated in the aging process and age-related disease such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities for $ONOO^-$ and its precursors, NO and ${\cdot}{O_2}^-$ of Vespae Nidus. Methods : Dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used to investigate scavenging activities of $ONOO^-,\;NO,\;{\cdot}{O_2}^-$. Six-months-old ICR mice were used. After mice were injected with lipopolysaccharides(LPS), kidney organization was evaluated. Three comparison groups of ICR mice were used : a normal group, an experimental group that was fed Vespae Nidus extract and then injected with LPS, and a control group that was injected with LPS. Scavenging activities of $ONOO^-,\;NO,\;{\cdot}{O_2}^-$ in these groups were measured in the same way. Results : Vespae Nidus markedly scavenged authentic $ONOO^-,\;{\cdot}{O_2}^-$ and NO. It also inhibited $ONOO^-$ induced by ${\cdot}{O_2}^-$ and NO which are derived trom SIN-1. Furthermore, it inhibited $ONOO^-,\;{\cdot}{O_2}^-$, and NO generation by Vespae Nidus in LPS-treated ICR mouse kidney postmitochondria. Conclusions : These results suggest that Vespae Nidus might be developed as an effective $ONOO^-,\;{\cdot}{O_2}^-$, and NO scavenger for the prevention of the aging process and age-related diseases.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.125-133
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• 2003

Chemical properties and physiological activities of the freeze-dried synnemata of Beauveria bassiana were examined. A proximate analysis showed that the synnemata consisted mainly of carbohydrate (49.86%), protein 11.36%), and a moisture content of 30.64%. It contained a low amount of crude ash (4.76%) and fat (3.38%). The carbohydrate was composed mainly of mannose (52.3%), galactose (31.5%), glucose (13.2%), and rhamnose (3%). Trace amounts of arabinose, xylose, and fructose were present. Major amino acids In the synnemata were glutamic acid, glycine, aspartic acid, arginine, threonine, alanine, valine, leucine, lysine, and aspartic acid with the amounts of 30.42, 25.22, 17.17, 15.12, 12.65, 15.23, 12.47, 11.47, 14.24, and 17.17 mg/g, respectively. Among extracts from the synnemata, the hot-water extract showed 67% of anticomplementary activity compared to that of the positive control, followed by ethyl acetate extract (17%) and methanol extract (15%). The hot-water extract also had anticoagulant activity with 55 sec of coagulating time and this fraction exhibited the most potent Intestinal immune system modulating activity. The methanol extract showed the highest inhibitory activity (25%) on the 12-O-tetradecanoyl phorbol-13-acetate-induced superoxide ($O_2^-$) generation, followed by hot-water extract (18%) and ethyl acetate extract (10%). The data in the present study indicate that the extract of Beauveria bassiana synnemata contains some healthful chemical ingredients and it could provide beneficial physiological activities. These features of the synnemata should be of interest to the food industry as well as other industrial fields.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.579-585
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• 2015

BACKGROUND/OBJECTIVES: Sonchus asper is used extensively as an herbal anti-inflammatory for treatment of bronchitis, asthma, wounds, burns, and cough; however, further investigation is needed in order to understand the underlying mechanism. To determine its mechanism of action, we examined the effects of an ethyl acetate fraction (EAF) of S. asper on nitric oxide (NO) production and prostaglandin-E2 levels in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. MATERIALS/METHODS: An in vitro culture of RAW264.7 macrophages was treated with LPS to induce inflammation. RESULTS: Treatment with EAF resulted in significant suppression of oxidative stress in RAW264.7 macrophages as demonstrated by increased endogenous superoxide dismutase (SOD) activity and intracellular glutathione levels, decreased generation of reactive oxygen species and lipid peroxidation, and restoration of the mitochondrial membrane potential. To confirm its anti-inflammatory effects, analysis of expression of inducible NO synthase, cyclooxygenase-2, tumor necrosis factor-${\alpha}$, and the anti-inflammatory cytokines IL-$1{\beta}$ and IL-6 was performed using semi-quantitative RT-PCR. EAF treatment resulted in significantly reduced dose-dependent expression of all of these factors, and enhanced expression of the antioxidants MnSOD and heme oxygenase-1. In addition, HPLC fingerprint results suggest that rutin, caffeic acid, and quercetin may be the active ingredients in EAF. CONCLUSIONS: Taken together, findings of this study imply that the anti-inflammatory effect of EAF on LPS-stimulated RAW264.7 cells is mediated by suppression of oxidative stress.

• Journal of the Korean Chemical Society
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• v.34 no.2
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• pp.189-196
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• 1990

8-Acyl-2-hydroxyphenazine-5,10-dioxides and 8-acyl-2-aminophenazine-5,10-dioxides were synthesized by the reaction of hydroquinone and 4-aminophenol with 6-acylbenzofuroxans which had been obtained from acetanilide and n-acyl chlorides bearing butanoyl, hexanoyl and octanoyl groups. The antimicrobial activities of these phenazine dioxide derivatives were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxide derivatives bearing octanoyl group was stronger than that of those bearing butanoyl and hexanoyl groups in gram positive microorgamisms, but it was observed that the antimicrobial activity and the number of the carbon atom of acyl groups did not have any relation in gram negative microorganisms. When the activity of xanthine oxidase which is the key enzyme in the generation of superoxide anion radical ($O_2^-$), was measured in the presence of phenazine dioxide derivatives, the inhibitory action of the enzyme activity of 8-acyl-2-hydroxyphenazine-5,10-dioxides was increased in accordance with the number of the carbon atom of acyl groups.

• Journal of Environmental Science International
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• v.21 no.12
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• pp.1435-1447
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• 2012

The present study was conducted to determine the effect of hexaconazole (HEX), a triazole fungicide, on the growth, yield, photosynthetic response and antioxidant potential in cucumber (Cucumis sativus L.) plants subjected to UV-B stress. UV-B radiation and HEX were applied separately or in combination to cucumber seedlings. The growth parameters were significantly reduced under UV-B treatment, however, this growth inhibition was less in HEX treated plants. HEX caused noticeable changes in plant morphology such as reduced shoot length and leaf area, and increased leaf thickness. HEX was quite persistent in inhibiting shoot growth by causing a reduction in shoot fresh and dry weight. HEX noticeably recovered the UV-B induced inhibition of biomass production. Significant accumutation in anthocyanin and flavonoid pigments in the leaves occurred as a result of HEX or UV-B treatments. HEX permitted the survival of more green leaf tissue preventing chlorophyll content reduction and higher quantum yield for photosystemII under UV-B exposure. HEX treatment induced a transient rise in ABA levels in the leaves, and combined application of HEX and UV-B showed a significant enhancement of ABA content which activates $H_2O_2$ generation. UV-B exposure induced accumulation of $H_2O_2$ in the leaves, while HEX prevented UV-B induced increase in $H_2O_2$, indicating that HEX serves as an antioxidant agent able to scavenge $H_2O$ to protect cells from oxidative damage. An increase in the ascorbic acid was observed in the HEX treated cucumber leaves affecting many enzyme activities by removing $H_2O_2$ during photosynthetic processes. The activities of antioxidant enzymes including catalase(CAT), ascorbate peroxidase(APX), superoxide dismutase(SOD) and peroxidase(POD) in the leaves in the presence of HEX under UV-B stress were higher than those under UV-B stress alone. These findings suggest that HEX may participate in the enhanced tolerance to oxidative stress. From these results it can be concluded that HEX moderately ameliolate the effect of UV-B stress in cucumber by improving the components of antioxidant defense system.

• Journal of Environmental Science International
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• v.20 no.12
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• pp.1509-1519
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• 2011

The protective effect of nitric oxide (NO) on the antioxidant system under paraquat(PQ) stress was investigated in leaves of 8-week-old lettuce (Lactuca sativa L.) plants. PQ stress caused a decrease of leaf growth including leaf length, width and weight. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated PQ stress induced growth suppression. SNP permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under PQ exposure, suggesting that NO has protective effect on chloroplast membrane in lettuce leaves. Flavonoids and anthocyanin were significantly accumulated in the leaves upon PQ exposure. However, the rapid increase of these compounds was alleviated in the SNP treated leaves. PQ treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in the leaves, while SNP prevented PQ induced increase in malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that SNP serves as an antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, superoxide dismutase (SOD) and catalase (CAT) in lettuce leaves in the presence of NO donor under PQ stress were higher than those under PQ stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger, to the lettuce leaves arrested SNP mediated protective effect on leaf growth, photosynthetic pigment and antioxidant systems. However, PTIO had little effect on lettuce leaves under PQ stress compared with that of PQ stress alone. The obtained data suggest that the damage caused by PQ stress is in part due to increased generation of active oxygen by maintaining increased antioxidant enzyme activities and SNP protects plants from oxidative stress. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative damage induced by PQ stress and thus confer PQ tolerance.

• Journal of Plant Biotechnology
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• v.36 no.3
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• pp.244-254
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• 2009

The hypersensitive reaction (HR) is the most common plant defense reaction against pathogens. HR is produced during both host- and nonhost-incompatible interactions. Several reports suggest that similarities exist between host and nonhost resistances. We assayed the pattern of generation of reactive oxygen species (ROS) and scavenging enzyme activities during nonhost pathogen-plant interactions (Xanthomonas campestris pv. campestris/Capsicum annuum L.) and incompatible host pathogen-plant interactions (Xanthomonas campestris pv. vesicatoria race1/Capsicum annuum L.). Both ${O_2}^-\;and\;H_2O_2 $ accumulated much faster during nonhost resistance when compared to the host resistance. The scavenging enzyme activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were also different during the host- and nonhost-incompatible interactions. CAT activity was much higher during nonhost resistance, and several new isozymes of SOD and POX were detected during nonhost resistance when compared to the host resistance. Lipoxygenase (LOX) activity was higher in host resistance than nonhost resistance during the early stages of infection. Interestingly, the nitric oxide (NO) radical accumulated equal amounts during both host and nonhost resistance at early stages of infection. Further studies are needed to determine the specific pathways underlying these differences between host and nonhost resistance responses.

• International Journal of Oral Biology
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• v.39 no.4
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• pp.229-236
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• 2014

Reactive oxygen species (ROS) and nitrogen species (RNS) are implicated in cellular signaling processes and as a cause of oxidative stress. Recent studies indicate that ROS and RNS are important signaling molecules involved in nociceptive transmission. Xanthine oxidase (XO) system is a well-known system for superoxide anions ($O{_2}^{{\cdot}_-}$) generation, and sodium nitroprusside (SNP) is a representative nitric oxide (NO) donor. Patch clamp recording in spinal slices was used to investigate the role of $O{_2}^{{\cdot}_-}$ and NO on substantia gelatinosa (SG) neuronal excitability. Application of xanthine and xanthine oxidase (X/XO) compound induced membrane depolarization. Low concentration SNP ($10{\mu}M$) induced depolarization of the membrane, whereas high concentration SNP (1 mM) evoked membrane hyperpolarization. These responses were significantly decreased by pretreatment with phenyl N-tert-butylnitrone (PBN; nonspecific ROS and RNS scavenger). Addition of thapsigargin to an external calcium free solution for blocking synaptic transmission, led to significantly decreased X/XO-induced responses. Additionally, X/XO and SNP-induced responses were unchanged in the presence of intracellular applied PBN, indicative of the involvement of presynaptic action. Inclusion of GDP-${\beta}$-S or suramin (G protein inhibitors) in the patch pipette decreased SNP-induced responses, whereas it failed to decrease X/XO-induced responses. Pretreatment with n-ethylmaleimide (NEM; thiol-alkylating agent) decreased the effects of SNP, suggesting that these responses were mediated by direct oxidation of channel protein, whereas X/XO-induced responses were unchanged. These data suggested that ROS and RNS play distinct roles in the regulation of the membrane excitability of SG neurons related to the pain transmission.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1209-1216
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• 2018

This study aimed to evaluate the antimicrobial activity of 2-phenylethynyl-butyltellurium (PEBT) in Escherichia coli and the relation to its pro-oxidant effect. For this, we carried out the disk diffusion test, minimum inhibitory concentration (MIC) assay, and survival curve analysis. We also measured the level of extracellular reactive oxygen species (ROS), activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and level of non-protein thiols (NPSH). PEBT at 1.28 and 0.128 mg/disk exhibited antimicrobial capability in the disk diffusion test, with an MIC value of 1.92 mg/ml, whereas PEBT at 0.96, 1.92, and 3.84 mg/ml inhibited bacterial growth after a 9-h exposure. PEBT at 3.84, 1.92, and 0.96 mg/ml increased extracellular ROS production, decreased the intracellular NPSH level, and reduced the SOD and CAT activities. Glutathione or ascorbic acid in the medium protected the bacterial cells from the antimicrobial effect of PEBT. In conclusion, PEBT exhibited antimicrobial activity against E. coli, involving the generation of ROS, oxidation of NPSH, and reduction of the antioxidant defenses in the bacterial cells.

• The Journal of Internal Korean Medicine
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• v.24 no.1
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• pp.75-83
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• 2003

Objectives : Peroxynitrite($ONOO^-$), formed from the reaction of $O2^-$ and NO, is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been involved in the aging process and age-related diseases such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities of $ONOO^-$ and its precursors, NO and $O_{2^-}$ and its scavenging mechanism of Zingiberis Rhizoma (ZR). Methods : To investigate scavenging activities of $ONOO^-,\;NO,\;O_{2^-}$ and its scavenging mechanism, we used fluorescent probes like DCFDA, DAF-2 and DHR 123. The $ONOO^-$ scavenging activity on ZR was assayed by measuring oxidized dihydrorhodamine 123 (DHR 123) by fluorometry. The scavenging efficacy was expressed as IC50, showing the concentration of each sample that is required to cause 50% inhibition of DHR 123 oxidation. In a separate study, the protective effect of ZR on $ONOO^-$-induced nitration of bovine serum albumin was investigated through immuno-assay with a monoclonal anti-nitryrosine antibody, and a horseradish peroxidase-conjugated anti-mouse secondary antibody from sheep. Results : ZR markedly scavenged authentic $ONOO^-,\;O_{2^-}$ and NO. It also inhibited $ONOO^-$ induced by $O_{2^-}$ and NO which are derived from SIN-1. The data demonstrated that ZR led to decreased $ONOO^-$ mediated nitration of tyrosine through electron donation. It also inhibited the nitration of bovine serum albumin induced by $ONOO^-$ in a dose-dependent manner. Furtheremore, it blocked LPS-induced ROS and RNS generation. Conclusions : These results suggest that ZR can be developed as an effective $ONOO^-$ scavenger for the prevention of aging process and age-related diseases.