• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.178-185
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• 2006

This study was to investigate the effect of 0.1% chitosan-ascorbate (CA) prepared with different molecular weight (223, 746, 1,110 and 2,025 kDa) of chitosan on the changes in antioxidant activity of mul-kimchi during storage at $10^{\circ}C$ for 20 days. Animal experiments were divided to 5 groups; normal control group (NC), high cholesterol diet group (HC), high cholesterol diet mul-kimchi diet group (HCKC), high cholesterol diet and CA2025 containing mul-kimchi administrated group (HCCA), and high cholesterol diet and 1/2 concentrated CA containing mul-kimchi administrated group (HC2CA). Mul-kimchi juice was administered 0.5 mL per 100 g body weight once a day and fed for 5 weeks. Electron donating activity of the 20 days-stored mul-kimchi with 0.1% CA showed higher activity (84.74~89.13%) than those of control and ascorbic acid mul-kimchi (35.04 and 75.04%). Superoxide dismutase activities of the kimchijuice with CA were higher in the higher molecular of chitosan. In the animal experiments, the average body weight of the HCCA and HC2CA group were lower 6.9% and 8.4% than that of HC control group, respectively. Hepatic glutathione content in HCCA and HC2CA group was increased 22.5% and 9.1% as compared to HC group. Hepatic glutathione S-transferase activities were significantly increased in the HCCA (219.9%) and HC2CA group (153.8%) compared to NC group. Hepatic superoxide dismutase activity was highest in the HCCA group, and the activities in CA groups were higher than those of NC and HC group.

• Journal of Life Science
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• v.26 no.11
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• pp.1275-1281
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• 2016

The principal objective of this fundamental research was to analyze the physicochemical properties the and antioxidative activity of Napa cabbage pickle (NCP) for development of low-salt pickles. NCP-1 was a smaller than NCP at amount soy sauce (10%). The pH of NCP and NCP-1 were $4.51{\pm}0.15$, $4.85{\pm}0.08$ immediately after preparation. The pH of NCP and NCP-1 was reduced to $4.08{\pm}0.05$ and $4.31{\pm}0.12$ over time during 60 days of storage. The acidity of the NCP and NCP-1 immediately after preparation were 0.51% and 0.38% and increased to 0.67% and 0.56% after 60 days of storage. The salinity for the NCP ranged from 1.71-2.22% and NCP-1 ranged from 1.18-1.63%. The L value, which indicates the lightness, was the highest at day 0 and the lowest at 60 day. The tensile strength value of NCP was $10.9{\pm}0.05kgf/cm^2$ and NCP-1 in $11.84{\pm}0.11kgf/cm^2$ at day 0 and then significantly decreased with time in storage. The cutting force of NCP was $1004{\pm}7.12gf/cm^2$ and NCP-1 in $845{\pm}5.27gf/cm^2$ at day 0, which increased over time in storage. The overall acceptability of NCP was the highest at day 30, but the overall acceptability of NCP-1 was the highest at day 45. NCP-1 extracts at day 60 showed the highest antioxidant activity of 66.04%, whereas the NCP extract at day 0 showed the lowest antioxidant activity of 45.41%. These results showed that depending on the content of the seasoning pickle difference in the antioxidant activity. Thus, the best pickled Napa cabbage is determined by a smaller amount soy sauce in NCP-1, and the results could provide a basis for improving the availability and quality of Napa cabbage.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.652-662
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• 2000

This study was performed to measure the mutagenicity of fish by cooking and storage. Mutagenicity of the fish extract was measured by Ames test(Salmonella typhimurium reversion assay with TA 100) in vitro and by micro-nucleus test in vivo. The fish samples screened in this study were white fish(Trichiurus, Croaker, Salted Croaker) and red fish(Saury pike, Mackerel, Yellowtail, Salmon). The number of revertants of red fish were significantly higher than that of white fish. And the mutagenicity of mackerel was higher than other red fish, so followed experiment was made by using the extract of mackerel. Mutagenicity of the samples cooked on microwave oven was the lowest, whereas there was no significant difference between the samples cooked on gas grill and the ones on electric grill. In the presence of S9 mixture, the methanol extract of mackerel showed 2∼4 times high values of mutagenicity in comparison with the extract without S9. The extract of mackerel cooked with various vegetable juices showed inhibitory effects on the mutagenicity in the order of green tea, ginger, and radish. Also, the number of revertants was increased in the stored samples. Mutagenicity of the samples stored in the refrigerator was higher than that of the freezer. In micronucleus test, the methanol extract treated with vegetable juice inhibited micro-nucleus formation in bone marrow by cyclophosphamide in the order of ginger, green tea, and radish. In TBA test, there was a tendency that TBA values were increased as the storage time increased. Also, the rancidity of sample were stored in the refrigerator was higher value than sample stored in the freezer. Samples cooked on microwave oven showed the highest value in rancidity. When the antioxidant effect of vegetable juice was measured by electron donating ability(EDA) of mackerel cooked with vegetable juice to DPPH, the samples treated with onion showed the highest value of EDA(%), and the samples treated with green tea, ginger and cabbage also showed the antioxidant effect.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.806-816
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• 2013

This study was conducted to evaluate the quality characteristics of yoghurt added with 1.0%, 3.0% and 5.0% Bokbunja wine (BW) during the preparation of yoghurt. Changes of lactic acid bacterial population, pH, and total titratable acidity (TA) were monitored during the fermentation and storage of yoghurt. The pH was decreased in all the treatments, also TA and viscosity were gradually increased during the fermentation. The viscosity of yoghurt added with 5.0% BW was higher than another group. The sensory test, total phenolic acid and the anthocyanins content of the yoghurt were measured. The results of this analysis showed that higher amounts of total TA, viscosity, lactic acid bacterial population, total phenolic acid content and sensory test were observed in the yoghurt supplemented with the BW than those of yoghurt not supplemented with the BW. Sensory scores in yoghurt added 5.0% BW were significantly higher than the other groups in taste. When the BW yoghurt was kept at $4^{\circ}C$ for 12 d, its quality-keeping properties were relatively good. The combined results of this study suggest that yoghurt supplementing with BW produces additional nutrients while maintaining the flavor and quality.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.1-26
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• 1993

The purpose of this study was to investigate the effect of acid etching on the surface appearance and fracture toughness of five glass ionomer cements. Five kinds of commercially available glass ionomer cements including chemical curing filling type, chemical curing lining type, chemical curing metal reinforced type, light curing tilling type and light curing lining type were used for this study. The specimens for SEM study were fabricated by treating each glass ionomer cement with either visible light curing or self curing after being inserted into a rubber mold (diameter 4mm, depth 1mm). Some of the specimens were etched with 37% phosphoric acid for 0, 15, 30, 60, go seconds, at 5 minutes, 1 hour and 1 day after mixing of powder and liquid. Unetched ones comprised the control group and the others were the experimental groups. The surface texture was examined by using scanning electron microscope at 20 kV. (S-2300, Hitachi Co., Japan). The specimens for fracture toughness were fabricated by curing of each glass ionomer cement previously inserted into a metal mold for the single edge notch specimen according to the ASTME399. They were subjected to a three-point bend test after etching for 0, 30, 60, and 90 seconds at 5 minutes-, 1 hour-and 1 day-lapse after the fabrication of the specimens. The plane strain fracture toughness ($K_{IC}$) was determined by three-point bend test which was conducted with cross-head speed of 0.5 mm/min using Instron universal testing machine (Model No. 1122) following seven days storage of the etched specimens under $37^{\circ}C$, 100% humidity condition. Following conclusions were drawn. 1. In unetched control group, crack was present, but the surface was generally smooth. 2. Deterioration of the surface appearance such as serious dissolving of gel matrix and loss of glass particles occured as the etching time was increased beyond 15 s following Immediate etching of chemical curing type of glass ionomer cements. 3. Etching after 1 h, and 1 d reduced surface damage, 15 s, and 30s etch gave rough surface appearance without loss of glass particle of chemical curing type of glass ionomer cements. 4. Light curing type glass ionomer cement was etched by acid, but there was no difference in surface appearances according to various waiting periods. 5. It was found that the value of plane stram fracture toughness of glass ionomer cements was highest in the light curing filling type as $1.79\;MNm^{-1.5}$ followed by the light curing lining type, chemical curing metal reinforced type, chemical curing filling type and chemical curing lining type. 6. The value of plane stram fracture toughness of the chemical curing lining type glass ionomer cement etched after 5 minutes was lower than those of the cement etched after 1 hour or day or unetched (P < 0.05). 7. Light curing glass ionomer cement showed Irregular fractured surface and chemical curing cement showed smooth fractured surface.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.445-453
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• 2016

Eighty-four strains of lactic acid bacteria were isolated from Korean fermented foods for the production of fermented apple juice. Among these strains, the JBE245 strain that showed rapid growth and food functionality was selected and identified as Lactobacillus plantarum. This strain reached the stationary phase after 24 h fermentation at $30^{\circ}C$ with $1.5{\times}10^8$ colony forming unit (CFU)/mL of viable cells, and maintained its viability levels even after 14 days of storage. During fermentation, the ${\alpha}-glucosidase$ inhibitory activity (40.4%), total polyphenol content (583.6 mg gallic acid equivalent (GAE)/mL), and 2,2-diphenyl-l-picryl-hydrazyl hydrate (DPPH) radical scavenging activity (52%) were increased. As judged by a sensory test, the overall preference for the fermented juice (4.22) was comparable to that for the unfermented juice (4.72), indicating that fermentation does not significantly affect the sensory characteristics of apple juice. Consequently, the fermented beverage containing L. plantarum JBE245 and apple juice is a promising functional health food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.891-896
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• 2006

The chemical components and antimicrobial effects were investigated to provide basic data that will predict the usefulness of Corni fructus as food materials. The carbohydrate, crude protein, lipid and ash contents of Corni fructus were 87.7, 3.2, 4.5 and 4.6% in dry basis, respectively. Total amino acid content of Corni fructus was 2,470 mg%. Major amino acids of Corni fructus were aspartic acid (523 mg%) and glutamic acid (247 mg%). The compositions of total saturated and unsaturated fatty acids of Corni fructus were 30.8% and 69.2%, respectively. Major fatty acids of Corni fructus were linolic acid (33.3%), palmitic acid (25.1%), linolenic acid (21.6%) and olcic acid (13.2%). The mineral contents of Corni fructus were 2067.5 mg% of K, 372.9 mg% of Ca and 98.4 mg% of Mg in dry basis. The organic acid contents of Corni fructus were 19,478 mg% of formic acid, 18,167 mg% of succinic acid, 14,487 mg% of malonic acid and 13,018 mg% of malic acid. Naengmyon yuksu (beef stock for cold noodles) were prepared with the addition of Corni fructus. Corni fructus added to Naengmyon yuksu inactivated microorganism and inhibited the growth of microorganism during storage at $10^{\circ}C$. Naengmyon yuksu added 1.5 g of Corni fructus showed the highest sensory scores.

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.148-156
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• 2015

In this study the differences in the sample size and sample input changes as characteristics of bio-oil oak(Quercus variabilis), the oak 0.5~2.0 mm of the oak weighing 300~900g was processed into bio-oil via fast pyrolysis for 1.64 seconds. In this study, the physico-chemical properties of biooil using oak were investigated. Fast pyrolysis was adopted to increase the bio-oil yield from raw material. Although the differences in sample size and sample input changes in the yield of pyrolysis products were not significantly noticeable, increases in the yield of bio-oil accounted for approximately 60.3 to 62.1%, in the order of non-condensed gas, and biochar. When the primary bio-oil obtained by the condensation of the cooling tube and the seconary bio-oil obtained from the electric dust collector were measured separately, the yield of primary bio-oil was twice as higher than that of the secondary bio-oil. However, HHV (Higher Heating Value) of the secondary bio-oil was approximately twice as higher than that of the primary bio-oil by up to 5,602 kcal/kg. The water content of the primary bio-oil was more than 20% of the moisture content of the secondary bio-oil, which was 10% or less. In addition, the result of the elemental analysis regarding the secondary bio-oil, its primary carbon content was higher than that of the primary bio-oil, and since the oxygen content is low, the water content as well as elemental composition are believed to have an effect on the calorific value. The higher the storage temperature or the longer the storage period, the degree of the viscosity of the secondary bio-oil was higher than that of the primary bio-oil. This can be the attributed to the chemical bond between the polymeric bio-oil that forms during the storage period.

• Korean journal of food and cookery science
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• v.25 no.4
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• pp.435-444
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• 2009

In this study, Paeonia japonica powder was extracted with ethanol, and its antimicrobial activity was investigated. The ethanol extract of the P. japonica had antimicrobial activity against Bacillus subtilis, Escherichia coli and Staphylococcus aureus. The inhibition zones of the P. japonica ethanol extract (3 mg/disc) against B. subtilis, E. coli and S. aureus were 10, 11, 8.5 mm, respectively. To test the food preservation effect of P. japonica and determine the optimal ratio of the P. japonica extract in the formulation, Sulgidduk samples were prepared with substitutions of 0, 0.25, 0.5, 0.75 and 1% P. japonica extract, and the quality characteristics of the samples were then investigated over 4 days of storage. In these experiments, total cell counts tended to decrease as the amount of added P. japonica extract increased. Moisture contents were not significantly different among the Sulgidduk samples. As the content of the P. japonica extract increased, the L-values of the samples decreased and the a- and b- values increased. In regards to the textural characteristics, the hardness, gumminess, and chewiness of the Sulgidduk samples decreased as the amount of P. japonica extract increased; however, they increased with the progression of storage time. Adhesiveness, springiness and cohesiveness were not significantly different at the different P. japonica extract concentrations and decreased with storage time. In the sensory evaluation, the control group had significantly higher scores for color, flavor and after taste as compared to the P. japonica extract added groups. When the P. japonica extract content was increased, the flavor and overall acceptability decreased, while Bakjakyak flavor, bitterness and off-flavor increased. Softness was not significantly different among the samples. In conclusion, the results indicate that substituting $0.25{\sim}1%$ P. japonica extract in Sulgidduk is optimal for quality and provides a product with reasonably high overall acceptability.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.1-11
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• 2005

The application of Dongchimi liquid into Naengmyon broth for the improved eating quality of Naengmyon was scientifically explored by reviewing the quality properties of the product. Primarily, the optimum fermentation conditions for Dongchimi from which the liquid portion was extracted were pursued and the optimum mixing ratio was sought on the basis of sensory and microbiological properties of the product. The liquid portions which had been periodically extracted from Dongchimi at intervals of two or five days during fermentation at $10^{\circ}C$ were added to Naengmyon broth. The treatments were prepared with three levels, namely, basic broth only('A') and the ratios of 3:7(v/v, 'B') and 5:5(v/v, 'C') of Dongchimi liquid and basic broth, respectively. According to assessments of Dongchimi liquid on taste and intensity based on sensory analyses, the organoleptic factors such as color, smell, sour taste, carbonated taste, and overall acceptability were given higher values from day 11 to day 17 in all items. As for the assessment of Dongchimi liquid on intensity, color, sour odor, moldy odor, and carbonated taste have shown the increasing scores during with high intensities while those for clearness has stayed low. Most of the phenomena observed from the Naengmyon broth substituted with $30\%$ (Treatment 'A') and $50\%$ (Treatment 'B') of Dongchimi liquids with different storage periods ensued much of the previous fermentation pattern of Dongchimi itself. Organoleptic assessment on taste and its intensity showed that better(the best) scores could be obtained at between day 16$\~$25(17) and 13$\~$20(15) for Treatments A and B, respectively. The intensity scores of taste for color, smell, carbonated taste, sour taste, and mouthfeel were increased while those for clearness, palatability, and meaty ones were decreased with lapse of fermentation. The numbers of total cell and lactic acid bacterial counts of Dongchimi has increased until day 13 and then decreased in the later stages. Total cell count and lactic acid bacterial counts of Naengmyon broth also increased until the 13th day and then they began to decrease. It was also proven that slightly over-ripened Dongchimi liquid was more preferable for adding into Naengmyon broth. Granting the optimum ripening period of Dongchimi liquid itself to be 13 days, both Treatment A and Treatment B were evenly favored using Dongchimi liquids slightly over-ripened at days 13 to 17. However, Treatment A was more favored than Treatment B when Dongchimi liquid over-ripened for 20 to 26 days was used.