• The Korean Journal of Pharmacology
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• v.32 no.2
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• pp.211-219
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• 1996

The inhibitory effect of cyclosporin A (CsA) on nitric oxide production is not related to the immunosuppressive action of the drug, but to the renal toxicity and arterial hyper-tension. In this study the experimental interventions to reverse the inhibition of nitric oxide production by cyclosporin A in rat aortic smooth muscle cells were examined. CsA inhibited the accumulation of nitrite, the stable end product of nitric oxide, in culture media in a concentration $(0.1{\sim}100{\mu}g/ml)-dependent$ manner. The inhibitory effect of CsA on nitrite accumulation were not antagonized by arginine (10 mM), a substrate of nitric oxide synthase, nor by calcium ionophore A23187 $(7{\mu}M)$. Forskolin, an activator of adenylate cyclase, which enhanced iNOS induction at transcriptional level, completely reversed the inhibitory action of CsA on nitrite accumulation. However, PMA (2 nM) and PDB (50 nM), PKC activators, increased the inhibitory action of CsA on nitrite accumulalion. From these results, it is suggested that cyclic AMP-elevating agents may be candidates of therapeutic agents in prevention and treatment of renal toxicity and arterial hypertension induced by CsA. Among conventional antihypertensive drugs, calcium channel blockers and ${\alpha}-blockers$ are preferred to ${\beta}-blockers$.

• Advances in Traditional Medicine
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• v.5 no.3
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• pp.209-215
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• 2005

This study was conducted to investigate the efficacy of antioxidative activity and nitrite scavenging ability of each fractions from Phyllostachys bambusoides S. et Z. (P. bambusoides) trunk ethanolic extract using reverse-phase flash chromatography. Among the each fractions, fraction 3 $(H_2O\;:\;MeOH\;=\;1:1)$ showed high DPPH free radical scavenging activity (81.33%) at $80\;{\mu}g/mL$ concentrations and strongly inhibited autooxidation of pyrogallol by superoxide dismutase-like activity (45.8 %) at 0.46 mg/mL concentrations compared with different fractions. The fraction 3 was also increased to 76.62% cell viability against hydrogen peroxide-mediated cytotoxicity. Nitrite scavenging ability was the most remarkable under pH 1.2 condition among various pH regions examined and effectively exhibited to 65.6% by treatment of the fraction 3 with a concentration of 0.2 mg/ml. In general, nitrite scavenging ability decreased with higher pH condition. These results suggest that fraction 3 from P. bambusoides ethanolic extract can be used for bioacitve and functional materials.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.333-337
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• 2003

This study was conducted to estimate the biofunctional characteristics, namely nitrite scavenging effect of barley leaves (BL) and their mixture (AM) with other antioxidants. Aqueous or methanol extracts were obtained from BL and AM. Aqueous and methanol extracts from barley leaves had relatively higher nitrite scavenging effects and its activities and contents increased in a concentration-dependent manner. The activities and contents of methanol extracts obtained from BL and AM were higher than those of aqueous extracts. Especially, AM containing BL and other antioxidant mixture had the highest activities and contents increased in a concentration-dependent manner. BL or AM were added to macrophage cells of RAW 264.7. Survival rates of the cells treated with BL and AM were measured to be different. $IC_{50}$ value decreased in a concentration-dependent manner by the addition of aqueous or methanol extracts from BL and AM. Especially, methanol extracts of AM had the highest nitrite scavenging effects. Thus, BL and AM may have protective effect against carcinogen and immune ability against reactive molecules through NO (nitric oxide) signal pathway. From the above results, barley leaves appear to contain natural anticancer and immune-related agents and may have potentiality to be used as functional food ingredients.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.379-383
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• 2008

Extraction characteristics of garlic and functional properties of corresponding extract were monitored by response surface methodology (RSM). Maximum extraction yield of 26.41% was obtained at microwave power of 146.29 W, ethanol concentration of 63.31 %, and extraction time of 5.88 min. At microwave power, ethanol concentration, and extraction time of 114.84 W, 58.83%, and 1.42 min, respectively, maximum electron-donating ability (EDA) was 72.86%. Maximum nitrite-scavenging ability was 94.62% at microwave power, ethanol concentration, and extraction time of 81.83 W, 2.65%, and 3.83 min, respectively. Superoxide dismutase (SOD) showed maximum pseudo-activity of 49.12% at microwave power of 34.23 W, ethanol concentration of 33.11 %, and extraction time of 4.40 min. Based on superimposition of 4-dimensional RSM with respect to extraction yield, electron-donating ability, nitrite-scavenging ability, and pseudo-activity of SOD, optimum ranges of extraction conditions were microwave power of 0-100 W, ethanol concentration of 40-70%, and extraction time of 2-8 min.

• Corrosion Science and Technology
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• v.17 no.5
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• pp.203-210
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• 2018

This paper compares the inhibition properties of aspartic and lactic acid salts with nitrite ions and their effect on critical chloride concentration. The tests were carried employing carbon steel specimens in saturated lime solution with varying pH in the range between13 to 13.6. The critical chloride concentration was estimated through multiple specimen potentiostatic tests at potentials in the usual range for passive rebar in the alkaline concrete of atmospheric structures. During tests, chloride salt was added every 48 h until all the specimens showed localized attacks. The cumulative distribution curves, i.e. the number of corroded specimens as a function of the chlorides concentration was obtained. Furthermore, IR spectra were recorded for the evaluation of the presence of the organic inhibitors on the passivity film. The results confirmed the inhibitory effect of 0.1M aspartate comparable with nitrite ions, at a similar concentration. Addition of calcium lactate did not result in an increase in the critical chloride concentration. However, the formation of a massive scale containing the substance that could reduce the corrosion propagation was observed.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.299-305
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• 2007

Response surface methodology was employed to optimize extraction conditions for finding the maximal functional properties of Pleurotus eryngii. Based on central composite design, the study plan was established with variations of microwave power (30-150 W), ethanol concentration (0-99.9%), and extraction time (1-9 min). Regression analysis was applied to obtain a mathematical model. A maximal yield of 47.86% was obtained when the microwave power, ethanol concentration, and extraction time were set at 122.7 W, 42.14%, and 8.3 min, respectively. A maximized electron donating ability of 93.32% was found under the following conditions: a microwave power of 144.19 W, an ethanol concentration of 49.52%, and an extraction time of 6.7 min. When the microwave power, ethanol concentration, and extraction time were set at 125.43 W, 40.54%, and 8.1 min, respectively, the maximum nitrite-scavenging ability was 80.47%. The optimum ranges of the extraction conditions, superimposed by the response surface methodology, could predicate a microwave power of 110-150 W, ethanol concentration of 0-45%, and extraction time of 7-9 min.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.307-312
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• 2011

In this study, we evaluated the antioxidant activities and xanthine oxidase inhibition effects of water and ethanol extracts of Cynomorium songaricum. The ethanol extract of C. songaricum (EE) contained more phenolic and flavonoid compounds than the water extract (WE). The antioxidant activities of the extracts were increased as the concentration of the extract increased. The WE has better effectiveness than the EE for DPPH free radical scavenging activity and nitrite scavenging ability. The nitrite scavenging abilities of WE were 90.02% ($EC_{50}$ 653.15 ${\mu}g$/mL) at conditions of pH 1.2 and 2,000 ${\mu}g$/mL, and 84.34% ($EC_{50}$ 817.17 ${\mu}g$/mL) at pH 3.0. The EE has more effective SOD-like activity and XO inhibition than WE. The SOD-like activity of EE was 81.47% at a concentration of 2,000 ${\mu}g$/mL, $EC_{50}$ was 951.70 ${\mu}g$/mL. The xanthine oxidase inhibition of the EE, with an $EC_{50}$of 112.47 ${\mu}g$/mL, is greater than that of ascorbic acid, which was 192.50 ${\mu}g$/mL (p<0.05). These results suggest that the C. songaricum is a potentially useful antioxidant source for the development of nutraceuticals and medicines.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.2
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• pp.183-189
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• 2014

We investigated noodles supplemented with functional ingredients for their antioxidant properties, including total phenol, flavonoid contents, electron donating, nitrite scavenging abilities and ferrous ion chelating effect. The total polyphenol contents of functional noodles arranged in order of decreasing concentration were kudzu (7.98%) > green tea (4.99%) > pumpkin (5.03%) > mulberry leaves (4.99%) > mugwort (4.23%) > cactus (3.57%) > kelp (3.33). The total flavonoid contents in green tea noodles were the highest as 4.35%. The electron donating ability in mugwort noodle was the highest as 12.27% at 1,000 ppm. This amount was 4.85 times than that of wheat flour noodle (2.53%). The nitrite scavenging ability of functional noodles at pH 1.2 arranged in order of decreasing concentration were green tea (66.52%) > cactus (55.12%) > kudzu (52.67%) > pumpkin (50.50%) > mulberry leaves (43.58%) > kelp (41.41%) > mugwort (37.66). The nitrite-scavenging ability of green tea noodle was lower than ascorbic acid (natural antioxidant) 77.83%, while that of green tea noodle was similar with BHT (artificial antioxidant) 69.45%. The ferrous ion chelating effect of noodles containing kelp were the highest as 27.02%. All of the experimental results showed good antioxidant property. Thus, noodles supplemented with mulberry leaves, cactus, mugwort, green tea, pumpkin, kelp or kudzu, demonstrated to have good functional effects for human health.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.113-122
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• 2002

A bench-scale anoxic membrane bioreactor (MBR) system, consisting of a bioreactor coupled to a ceramic crossflow ultrafiltration module, was evaluated to treat a synthetic wastewater containing alkaline hydrolysis byproducts (hydrolysates) of RDX, The wastewater was formulated the same as RDX hydrolysates, and consisted of acetate, formate, formaldehyde as carbon sources and nitrite, nitrate as electron accepters. The MBR system removed 80 to 90% of these carbon sources, and approximately 90% of the stoichiometric amount of nitrate, 60% of nitrite. The reactor was also operated over a range of transmembrane pressures, temperatures, suspended solids concentration, and organic loading rate in order to maximize treatment efficiency and permeate flux. Increasing transmembrane pressure and temperature did not improve membrane flux significantly. Increasing biomass concentration in the bioreactor decreased the permeate flux significantly. The maximum volumetric organic loading rate was $0.72kg\;COD/m^3/day$, and the maximum F/M ratio was 0.50 kg N/kg MLSS/day and 1.82 kg COD/kg MLSS/day. Membrane permeate was clear and essentially free of bacteria, as indicated by heterotrophic plate count. Permeate flux ranged between 0.15 and $2.0m^3/m^2/day$ and was maintained by routine backwashing every 3 to 4 day. Backwashing with 2% NaOCl solution every fourth or fifth backwashing cycle was able to restore membrane flux to its original value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.349-355
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• 2000

Onion was extracted by methyl alcohol and some physiological activities and antioxidative effect of the extracts on soybean oil, corn oil, lard and shortening were compared with commercial antioxidants such as $\alpha$-tocopherol and BHT. The electron donating ability was about 70% at concentration above of 30mg/mL. Nitrite scavenging effects of all concentrations diminished at higher pH, while in the case of pH 1.2, it showed a nitrite scavenging effect of more than 80% af concentration above of 30mg/mL. And also, the angiotensin I-converting enzyme inhibitory effect was good above 80%. The soybean oil, corn oil, lard and shortening containing different levels of the onion extract were stored at 6$0^{\circ}C$ to evaluate the antioxidative activity of onion extracts. Peroxide value, acid value and TBA value of each oil were detected. Onion extract was very effective to retard oxidation of soybean oil, corn oil and lard, and especially, the very high antioxidative effect was observed for lard.