• Molecules and Cells
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• v.22 no.3
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• pp.336-342
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• 2006

Real time reverse transcription (RT)-PCR was used to quantify the expression of the botulinum neurotoxin type A (BoNT/A) gene (cntA) by normalization with the expression of 16S rRNA. The method were confirmed by monitoring the mRNA levels of cntA during growth in five type A strains. In all but one of the strains the expression of cntA mRNA was maximal in the late exponential phase, and approximately 35-fold greater than in the early exponential phase. The concentration of the extracellular BoNT/A complex detected by ELISA was highest in stationary phase. Sodium nitrite and sorbic acid completely inhibited growth at 20 ppm and $4mg\;ml^{-1}$, respectively. CntA expression became lower in proportion to the concentration of sorbic acid, and this reduction was confirmed by mouse bioassay. Our results show that real time RT-PCR can be used to quantify levels of C. botulinum type A neurotoxin transcripts and to assess the effects of food additives on botulinal risk.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.774-781
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• 2015

The objective of the present study was to determine the total phenol and flavonoid contents and to evaluate the antioxidant potential, of different solvent extracts (ethyl acetate, n-butanol, chloroform, and water) from Robus idaeus in various radical scavenging models (DPPH activity, superoxide dismutase (SOD) activity, reducing power, and nitrite scavenging activity), along with their antimicrobial potential. Measurement of total phenol and flavonoid content of the ethyl acetate extract of R. idaeus was found to be significantly higher than those of the other extracts. The ethyl acetate extract (at a concentration of $1,000{\mu}g/mL$) showed significantly higher reducing power and DPPH radical scavenging activity as compared to the other extracts. Results were dose-dependent. Moreover, the ethyl acetate extract of R. idaeus ($1,000{\mu}g/mL$) showed potent antioxidant efficacy ($85.5{\pm}1.18%$) as evidenced by nitrite scavenging ability at pH 1.2. All solvent extracts of R. idaeus showed lower SOD-like activity (13.72~20.54%). In addition, the antimicrobial activity of all solvent extracts except water extract showed strong inhibition (inhibitory zones in mm) of Staphylococcus aureus ($19.40{\pm}1.00mm$) and Bacillus cereus ($20.50{\pm}0.21mm$) growth. In particular, ethyl acetate extracts (100 mg/mL) showed antimicrobial activity comparable to that of tetracycline (0.01 mg/mL), which was used as a positive control. The results of this study indicate that the ethyl acetate extract of R. idaeus is a natural antioxidant and antimicrobial, with enriched phenols and flavonoids concentration, that has potential in the development of health-enhancing food products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.690-695
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• 1994

Simultaneous removal of phosphorus and nitrogen from wastewater was studied by the anaerobic-aerobic system of activated sludge. In the anaerobic stage, most of the influent glucose was removed and orthophosphate was released, when the nitrate and/or nitrite concentration in the wastewater was almost zero. The amount of the released phosphorus was found to be directly proportional to the amount of the removed glucose. When the ratio of phosphorus to glucose in the influent was less than 0.04, the phosphorus in the wastewater was almost completely removed during the aerobic state. Under the anaerobic condition, activated sludge released phosphate and excess removal of phosphate occurred during the aerobic condition. Namely, the stress received in anaerobic period stimulated the uptake of phosphorus in aerobic period. The amounts of phosphorus release in the anaerobic and uptake in the aerobic stage were less in proportional to the concentration of $NO_x-N$. Further, if the initial ratio of $NO_2-N$/glucose was less than 0.37, the inorganic nitrogen in the influent could be completely removed.

• The Korea Journal of Herbology
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• v.32 no.3
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• pp.29-36
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• 2017

Objectives : In order to investigate the possibility of Sorbus commixta Heal. stem (SC) as a natural material, antioxidant activities of the hot water and ethanol extracts were examined. Methods : The samples of SC were pulverized, and fractions were extracted repeatedly three times from hot water and 70% ethanol at room temperature for 2 hours. The antioxidant activities were analyzed from total polyphenol, flavonoid contents, DPPH, ABTS, hydroxyl radical, $Fe2^+$ chelating, and nitrite scavenging activity. Results : Total polyphenol contents were significantly higher in ethanol extract group ($504.39{\mu}g/m{\ell}$) than in hot water extract group ($364.64{\mu}g/m{\ell}$). Total flavonoid contents were also significantly higher in ethanol extract group ($160.09{\mu}g/m{\ell}$) than in hot water extract group ($124.59{\mu}g/m{\ell}$). DPPH, ABTS, $Fe2^+$ chelating were slightly higher in ethanol extract gorups than in hot water extract groups, and increased in a dose-dependent manner. The hydroxyl radical scavenging activity (18.42~23.61%) of ethanol extract groups were shown to be approximately twice higher than that (7.63~10.37%) of hot water extract groups at $12.5{\sim}50{\mu}g/m{\ell}$ concentration. Nitrite scavenging activities of both ethanol and hot-water extract groups were shown to be higher in a dose dependent manner at the concentration of $12.5{\sim}50{\mu}g/m{\ell}$ at pH 3.0 than at pH 1.2, and ethanol extract groups (86.55~96.64%) had higher activity than the hot water extract groups (42.59~92.63%), which was higher than that of the control group antioxidant BHT (72.96~80.11%). Conclusions : The extracts of SC displayed antioxidant activities which suggested a natural material can be developed to functional material.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.596-605
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• 2023

Sik-hae is a traditional Korean salt-fermented seafood having a low salt content and a high concentration of Lactobacillus, unlike most salt-fermented fish and fish sauce, which have a high salt content and low concentration of Lactobacillus. This study aimed to investigate the health-promoting functional properties of 10 types of commercial sik-haes. The results showed that for the commercial sik-haes studied, angiotensin-I-converting enzyme inhibitory activity, DPPH radical scavenging activity, α-glucosidase inhibitory activity, xanthine oxidase inhibitory activity, and sodium nitrite scavenging activity ranged from 29.0% to 46.3%, 35.5% to 65.4%, 0% to 20.0%, 20.1% to 78.8% , and 17.9% to 82.6%, respectively. Antimicrobial activity against Escherichia coli, Vibrio parahaemolyticus and Staphylococcus aureus was rarely detected. The results on healthy functional properties suggest that the commercial sik-haes are expected on the antioxidative activity in F-1-F-5, AP-1, BES, and S, xanthine oxidase inhibitory activity in the other 9 types expected for A, and sodium nitrite scavenging activity in the other 9 types expected for AP-2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.28-33
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• 2004

This study was performed to examine in vitro biological activities such as antioxidative, nitrite scavenging effect, tyrosinase inhibitory effect and antithrombotic activity of a Korean traditional prescription, Nogyong-daebotang, composed of oriental medical herbs and antler, nourishing the blood, helthiness, strengthening of vital power and promotion of growth. The concentration of total phenolic compounds of the prescription sample was 151.3$\pm$2.6 mg％. The electron donating abilities (EDA) by reduction of 2.2'-diphenyl-1-picrylhydrazyl (DPPH) was 80.9%, inhibition rate of lipid peroxidation in thiocyanate method used linoleic acid was 88.1%. Nitrite scavenging effects of the sample were more than 70% at acidic pH, but it was pH dependent, showing the highest at pH 1.2 and the lowest at pH 6.0. Inhibition rate against tyrosinase of the sample was above 80%. Platelet aggregation induced by ADP (adenosine-5'-diphosphate) was inhibited up to 30% and the inhibitory effect was dependent on concentration of the sample.

• Journal of Convergence for Information Technology
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• v.12 no.1
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• pp.119-126
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• 2022

In this study, the antioxidant ability, anti-inflammatory ability and whitening effect of the extracted Grateloupia filicina under optimal conditions were confirmed. The useful substances of Grateloupia filicina were extracted with various ethanol aqueous solutions to measure DPPH, ABTS, and nitrite radical elimination capabilities, and the polyphenol and flavonoid contents were analyzed. When extracted with a 20% ethanol aqueous solution, the radical elimination ability was the best, and the content of polyphenol and flavonoids was also the highest. From this, it was confirmed that the 20% ethanol aqueous solution efficiently extracted the antioxidant and anti-inflammatory substances of Grateloupia filicina. Meanwhile, the cytotoxicity and anti-inflammatory properties of the Grateloupia filicina extract were confirmed using RAW 264.7 cell lines. Grateloupia filicina extract did not show toxicity at a concentration of 200 ㎍/mL, and showed NO production inhibitory capacity of 50% or more at this concentration. As a result, it was confirmed that the Grateloupia filicina extract can be used as a functional cosmetic raw material having antioxidant and anti-inflammatory properties.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.5 s.57
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• pp.160-168
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• 2009

After steel bar was corroded it removes concrete contaminated, it does steel bar corrosion protection, repairing method and corrosion inhibitor spreading method are difficult to secure corrosion protection performance. Accordingly, in this research before Research and Development to penetrate corrosion inhibitor to high pressure by steel bar position, it measures penetration depth through corrosion inhibitor high pressure penetration experiment and amount of nitrite by position and then it predicts penetration depth in accordance with water-cement ratio, pressure, pressure time and it computed water-cement ratio, pressure, pressure time to be more than 0.6 mol ratio of chloride ion and nitrite to have outstanding corrosion protection performance. As a result of experiment, water-cement ratio gives the biggest influence to penetration of corrosion inhibitor and also the more depth of specimen becomes deep, concentration of penetrated corrosion inhibitor does not equal and becomes low.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.56-62
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• 2011

This study was conducted to investigate antioxidative and physiological activities of ethanol extracts from different parts (flower, leaf, root, and the whole plant) of Taraxacum officinale. The ethanol extracts from different parts were measured to examine total flavonoids content, total polyphenol content, elect ron donating ability,superoxide dismutase (SOD)-like activity, nitrite-scavenging ability and tyrosinase inhibition effects. Total flavonoids content in leaf extract (41.66 mg/g) and total polyphenol content in flower extract (71.91 mg/g) were higher than those of other parts. All assays were conducted at concentrations of 0.1, 0.3, 0.5, and 1 mg/mL ethanol extracts. The electron donating abilities of leaf, flower, the whole plant, and root extracts were 92.25%, 88.18%, 84.55% and 83.40%, respectively, at a concentration of 1 mg/mL. The activities were concentration dependent. The SOD-like activity of ethanol extracts from different parts was 8.40~11.20% at a concentration of 1 mg/mL. The nitrite-scavenging abilities of flower and leaf extracts measured at pH 1.2 were 47.37% and 47.18%, respectively, at a concentration of 1 mg/mL, which were higher than those of the whole plant and root extracts. Tyrosinase inhibition activity of the leaf extract at a concentration of 1 mg/mL was the highest (34.22%) and that of the whole plant and root extracts was shown to be more than 20%. These results suggest that ethanol extracts from different parts of Taraxacum officinale could be used as antioxidative functional food sources.

• Food Science and Preservation
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• v.17 no.5
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• pp.712-719
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• 2010

This study was carries out to analyzed the antioxidant activities and xanthine oxidase inhibitory effects of extracts from jujube to provide basic data for the development of functional materials. Antioxidative activities of extracts from jujube were analyzed by electron donating ability (EDA) using 1,1-diphenyl-2-picryl hydrazyl (DPPH), superoxide dismutase (SOD)-like activity by pyrogallol and nitrite scavenging ability. Extract yields from jujube fruits were 11.55% for unripe fruits, and about twice that value when ripe fruit extracts were prepared. The yields of hot-water and ethanol extracts was 55.67 and 65.95% in dried fruits, respectively. Total phenol contents were higher in unripe fruit extracts. The EDA values of hot-water and ethanol extracts from jujube fruits were increased by increase of extract concentration, and were about 90% in 10.0 mg/mL of extract concentration. The SOD-like activity was increased by the increase of extract concentrations. The SOD-like activity of the hot-water extract from unripe fruits was higher than that of other extracts. The SOD-like activity of ethanol extracts was 39.92% at 10 mg/ml of extract concentration from unripe fruits. The nitrite scavenging ability was about 50% in 1.0 mg/ml of extract concentration at pH 1.2, and that of extracts from unripe fruits was higher than that of other extracts. The xanthine oxidase inhibitory activities of hot-water and ethanol extracts from unripe fruits were higher than those of other extracts, were increased by concentration of extracts.