• Bulletin of the Korean Chemical Society
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• v.21 no.12
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• pp.1233-1238
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• 2000

$Mo/{\gamma}-Al_2O_3catalysts$ modified with Fe, Co, and Ni were prepared by impregnation method and catalytic activity for water gas shift reaction was examined. The optimum amount of Mo loaded for the reaction was 10 wt% $MoO_3$ to ${\gamma}-Al_2O_3.$ The catalytic activity of $MoO_3/{\gamma}-Al_2O_3was$ increased by modifying with Fe, Co, and Ni in the order of Co${\thickapprox}$ Ni > Fe. The optimum amounts of Co and Ni added were 3 wt% based on CoO and NiO to 10 wt% $MoO_3/{\gamma}-Al_2O_3$, restectively. The TPR (temperature-programmed reduction) analysis revealed that the addition of Co and Ni enganced the reducibility of the catalysts. The results of both catalytic activity and TPR experiments strongly suggest that the redox property of the catalyst is an important factor in water gas shift reaction on the sulfided Mo catalysts, which could be an evidence of oxy-sulfide redox mechanism.

• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.152-157
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• 2000

In order to select the optimum drying method for the production of cinnamon extract, water extract and 70% ethanol extract of cinnamon were prepared. And then several drying method of oven drying, vacuum evaporation, spray drying and freeze drying were performed. Content of cinnamic acid, cinnamic aldehyde, eugenol, tannin and free sugar, and antioxidant activity, degree of browning, pH, color value, turbity and solubility were compared. In water extract, contents of cinnamic acid, cinnamic aldehyde, eugenol were 29.45mg/100g, 94.86mg/100g, 120.75mg/100g and decreased to 4.76%∼44.21%, 5.30%∼48.05%, 3.66%∼21.83% by oven dyring, vaccum drying, spray drying respectively, but freeze drying showed a little decrease of those components. In 70% ethanol extract, effectual components decreased to 76.05%∼88.38% and 26.86%∼78.76% by freeze drying and vacuum evaporation respectively. Antioxidant activity decreased by drying and decreasing rate in 70% ethanol extract was lower than water extract. Degree of browning increased as the drying temperature increased. Tannin and free sugars were little affected by drying temperature. Solubility decreased in oven drying and 70% ethanol extract. Overall data suggested that optimum drying methods of cinnamon extract were freeze drying in case of water extract and freeze drying and vaccum drying in case of 70% ethanol extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1135-1139
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• 1997

Major factors inhibiting nonenzymatic browning in stored ginger paste were investigated using aqueous model systems with temperature, water activity, pH and sulfur compounds. Browning index and total gingerols were measured during storage. The rate of nonenzymatic browning reactions showed a strong depencence on temperature and pH and a negligible influence on water activity. It was also reduced by the addition of 0.04% N-actyl-L-cysteine(NAcCys), effectively. Activation energies for aqueous ginger model systems with and without 0.04% NAcCys were 29.0 and 25.8kcal/mole, respectively.

• The Korean Journal of Food And Nutrition
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• v.22 no.1
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• pp.41-47
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• 2009

This study investigated antioxidative and hypoglycemic activities of Omija for evaluation of usefulness as a functional food resource. Omija water extracts were extracted with water for 24 hr, 6 hr and 3 hr at room temperature, 60$^{\circ}C$ and 100$^{\circ}C$, respectively. Omija ethanol extracts were extracted with 60% ethanol for 24 hr and 3 hr at room temp temperature and 60$^{\circ}C$, respectively. The antioxidant properties of Omija(Schizandra chinensis Baillon) extracts prepared under different extraction conditions were evaluated by a variety of radical scavenging assays including DPPH, $ABTS^{{cdot}+}$, and nitrite and reducing power. Hypoglycemic activity was examined for $\alpha$-glucosidase inhibition using an in vitro model. The total phenolic content was also determined. Antioxidant activities of Omija were the highest in the group extracted with 60% ethanol for 3 hr. The ethanol extracts showed higher activity than water extracts. An extraction temperature was the highest in 60$^{\circ}C$. The total phenolic content extracted with 60% ethanol for 3 hr at 60$^{\circ}C$ was 530 mg GAE/100 g. The water extract extracted with water for 24 hr at room temperature showed the lowest antioxidant activity and phenolic content. $\alpha$-glucosidase inhibitory activity was the highest in the group extracted with 60% ethanol for 3 hr at 60$^{\circ}C$, followed by the group extracted with 60% ethanol for 24 hr. The results suggest that extraction of Omija by 60% ethanol for 3 hr at 60$^{\circ}C$ will be useful as a functional food resource with natural antioxidants and hypoglycemic activities.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.408-412
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• 2008

Determining the elution of water-soluble substances from herbal teas is an important factor in their efficient use in terms of taste, perfume, and content of health-related components. The antioxidant activity and content of catechins in commercial Chrysanthemum indicum (gamguk) teas were determined for optimum elution conditions. The water extract of gamguk teas did not differ significantly in yield compared to methanol extracts and showed stronger antioxidant activity. Catechin contents in gamguk teas were 8-18% of the extracts when individual peaks in high-performance liquid chromatography analysis were compared to standard catechin peaks. Gamguk teas exhibited faster release of antioxidants, and the antioxidant activity was positively correlated with the thermal treatments. Gukhwacha (GC) was the best tea for rapid release (30 sec) of antioxidants with the $50^{\circ}C$ treatment, whereas antioxidants in other teas were relatively slower released.

• Textile Coloration and Finishing
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• v.11 no.4
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• pp.31-38
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• 1999

The purpose of this study is to develop multifunctional fabric that has improved antimicrobial activity and reduction rate of gas by treatment of mixture of chito colla and crosslinking material for polyester. The surface morphology of treated PET fabric was studied by scanning electron microscopy(SEM). The properties of the PET fabric, such as antimicrobial activity, whiteness, moisture regain, water absorption and static voltage, and handle were investigated. Antimicrobial activity of treated PET fabric was proved 99%. The surface of treated PET fabric showed harshness and irregularity. The whiteness of treated PET fabric on the baking condition was decreased as time and temperature was increased. The moisure regain of treated PET fabric equally was maintained. Water absorption and static voltage of treated PET fabric were improved. KOSHI of treated PET fabric was increased compared with the untreated PET fabric H/W of treated PET fabric was improved compared with the untreated PET fabric and 2HB/B of treated PET fabric were reduced.

• Journal of Aquaculture
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• v.21 no.1
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• pp.41-46
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• 2008

The purpose of the study was to suggest the optimal lipid enrichment conditions used digestive enzyme activity of rotifer changing due to water temperature and salinity. The high population growth appeared at the experiment temperature more than 28 degrees highly on the culture temperature(maximum 32 degrees, 1,453 individual/mL). The fecundity was low at high temperature, and the egg ratio was high at low temperature. Population growth of 10 and 15 ppt appeared in most highly, but the fecundity and the egg ratio were high most significantly appeared in natural seawater(32 psu). The digestive enzyme activity by the culture environment mainly showed high activity in natural seawater(amylase exclusion, 15 psu). However, the TAP activity by the water temperature showed highly at the more high temperature, but the amylase and the lipase appeared at low temperature. We carried out the lipid enrichment at 20 degrees and 26 degrees in a condition of the natural seawater. Total protein, the total essential amino acids differed not significantly. The methionine content that was essential amino acids, a total lipid content, unsaturated index of fatty acids, DHA and the DHA/EPA ratio were high significantly each in $20^{\circ}C$ enrichment trial. Therefore, we could suggest the $20^{\circ}C$ and natural seawater for the optimal lipid enrichment condition in aquaculture, because methionine contents, several indexes by the lipid, TG-lipase activity, fecundity and egg ratio are high.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.288-293
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• 2002

Allergen-removed-extract was produced from Rush verniciflua by two phase methods. Phase one was high temperature treatment of Rush verniciflua tree to get allergen-removed-extract. Phase two was extraction of solution from phase one product using water or organic solvents. The solutions from above method show high antioxidant activity, anticancer activity, and improvement in lung function, but did not contain urushiol family compounds.

• Food Science and Preservation
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• v.10 no.1
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• pp.32-36
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• 2003

Quality stability of the dried layer Porphyra tenera depending on various light sources, water activities, packaging materials and storage temperatures were investigated by peroxide value and chlorophyll degradation. Major fatty acids of dried layer were 45.7％ eicosapentaenoic acid and 13.6% palmitic acid. Quality stability was increased in order of darkness, incandescent and fluorescent increased sharply with the decrease of water activity and temperature, and also improved by the packaging material with strong barriers of water vapor, oxygen and light.

• 수도
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• s.21
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• pp.24-32
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• 1980