• Food Science and Preservation
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• v.22 no.5
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• pp.751-757
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• 2015

The objective of this study was to investigate the protective effects of mulberry (Morus alba) sugar extracts (MSE) against $H_2O_2$-induced oxidative stress in HepG2 cells. The MSEs was mixed with matured mulberry and sugar at the same ratio (1:1, w/w) and stored at $18{\pm}3^{\circ}C$ for 40 days. In 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging test, MSE stored for 40 days showed high activity with a ratio above 66%. Therefore, we selected 40 days as the optimum storage period. After cell viability analysis using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, we determined that the optimum concentration of MSE was 0.5%. Our results showed that MSE increased the cell viability and antioxidant enzyme activities of superoxide dismutase (SOD) and catalase in $H_2O_2$-treated HepG2 cells. Moreover, the treatment with MSE inhibited malondialdehyde (MDA) levels in $H_2O_2$-treated HepG2 cells. We also observed a reduction in apoptotic bodies in the Hoechst staining. These data show that MSE treatment significantly suppressed caspase-3 activity in HepG2 cells expored to $H_2O_2$-induced oxidative stress, thereby indicationg the protective effects of MSE in $H_2O_2$-induced oxidative stress.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.246-253
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• 2003

Application of xylitol (Xyl) and grapefruit seed extract (GSE) to improve the quality and preservation of baechu kimchi was attempted. Xylitol and grapefruit seed extract at various combinatory concentrations were added into baechu kimchi and fermented for 25 days at $10^{\circ}C$. Assay was performed on sensory value, acidity, and bacterial growth. Addition of 0.1% GSE and 2% Xyl showed the highest score in the overall acceptability, sour taste, and texture. Score of intensity characteristics in smell and sour taste were the highest in the control and that of texture the highest in 0.1% GSE plus 2% Xyl treatment. The pH decreased, and titratable acidity, and growth of total viable cells and lactic acid bacteria were remarkably retarded in 0.1% GSE plus 2% Xyl group compared to the control. Results showed that application of 2% Xyl plus 0.1% GSE to the kimchi fermentation enhanced sensory value of the fermented product and extended the storage period by about twofold.

• Korean Journal of Food Science and Technology
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• v.11 no.2
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• pp.93-98
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• 1979

An attempt was made to investigate the antioxidant activity of methylene chloride extracts of a glucose-ammonia browning reaction mixture, which contain pyrazines, important intermediate prod ucts of Maillard-type browning reactions. Methylene chloride extracts were obtained from a glucose-ammonia(1M+8M) browning reaction mixture, which had been heated at $100^{\circ}C$. for 4 hours. The molar ratio of the reactants and the reaction time were reported to be the optimum ratio and time for the maximum formation of pyrazines. The methylene chloride extracts and furfural (for comparison purpose) were added to edible rapeseed oil substrates, and the resulting substrates and the control were stored at $37.0{\pm}1.0^{\circ}C$. Peroxide values (POV), thiobarbituric acid values (TBA-values) and acid values (AV) of the substrates and the control were determined regularly during a 34-day storage period. The antioxidant activity of the methylene chloride extracts and furfural was estimated on the basis of POV, TBA-value and AV-development of the substrates and the control. It was found that the methylene chloride extracts of the glucose-ammonia (1M+8M) browning mixture possessed considerable antioxidant activity. Furfural also showed some activity.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.736-742
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• 2012

In this study, the brewing and quality characteristics of a variety of honey and yeast strains in Korea were investigated. After fermenting acacia honey, chestnut honey, citrus honey, and mixed flower honey using commercial yeast, the quality changes during fermentation were investigated. Chestnut honey wine (mead) and mixed flower mead showed the highest ethanol contents of 11.9 and 11.3%, respectively after fermenting for 8 days at $25^{\circ}C$. Acacia mead and citron (Chinese lemon) mead showed 5.0 and 8.2% ethanol contents, respectively. Mixed mead, which fermented with acacia honey and mixed flower honey, in order to advance sensory properties, showed the best sensory properties, generating 10.9% ethanol, while another product with citron honey and mixed flower honey generated 11.1% of ethanol but with a lower sensory value. When adding corium peels to the mixed mead of acacia honey and mixed flower honey, the ethanol content was not increased by addition of corium peels into mixed mead, but its total acceptability was increased by addition of 2% corium peels. To check the mead clarification, it was treated with 0.6% of bentonite and filtered; then, its turbidity was observed over a storage period. The safe result for precipitation was shown at the condition of storing at $10^{\circ}C$ for 15 days with 0.24 NTU (Nepthelometric Turbidity Unit).

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.19-28
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• 1987

These experiments were conducted to recognize the germination change in relation to storage period, using 25 kinds of field-collected weed seeds stored under the dry and low temperature ($4{\pm}1^{\circ}C$), and to establish a simple germination induction methods in some kinds of them. No or weak dormancy was observed in Lepidium virginicum, Rumex japonicus, Cirsium japonicum var. ussuriense, Aeschnomene indica and Ludwigia prostrate. The germination of Digltaria sanguinalis, Portulaca oleracea, Amaranthus spp., Echinochloa crux-galli, Polygonum persicaria, Cyperus iria, and Aeschynnmene indica was enhanced by $H_2SO_4$ treatment for 20, 2, 2, 50, 40, 3 or 5 minutes, respectively. Favorable germination in Polygonum persicaria and Echinochloa crus-galli was obtained by soaking in water for 25 days and 50 days, respectively. Moisture treatment for 21 days and 14 days caused the enhancement of germination in Cyperus difformis and Aneilema keisak, respectively. Combination of various treatments in Cyperus iria was most effective when the seeds treated with $H_2SO_4$ for 3 minutes incubated in alternating temp. after soaking in 0.2% $KNO_3$, but their effect on Digitaria sanguinnlis was little.

• Journal of Environmental Health Sciences
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• v.6 no.1
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• pp.1-9
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• 1979

An experimental study was carried out to develop a rural type toilet of which the effluent could not transmit parasitic diseases at a village in Kangwon Province, Korea, during the period of January through December 1978, A drum tank (dia. 57cm$\times$90cm) and a cement tank (100cm$\times$100cm$\times$100cm) were filled with human excreta collected from toilets of the villages (the ratio of feces to urine was estimated approximately 1: 5) at once and three threecompartment toilets were constructed and used by people. pH, temperatures and viability of parasitic eggs were examined with the content of toilets. Rusults are summarized as follows: 1. pH increased from 7.0 at the beginning of experiment to 7.5 or 8.0 after 4 months of storage in drum tank as well as in cement tank and so did from 7.0~7.5 in the first tank to 8.0~8.5 in the third tank of all three-compartment toilets. 2. Temperatures of content at middle part of toilets in January through March ranged from 2 to 6$\circ$C which were 2-4$\circ$C higher than those of air, and those of lower part were again 1~2$\circ$C higher than of middle part. but temperatures of air, at middle part andat lower part in April were 14$\circ$C, 9~10$\circ$C and 8~9$\circ$C respectively, in July 29$\circ$C, 20~21$\circ$C and 19~20$\circ$C respe ctively and in October 17$\circ$C, 14$\circ$C and 14~13$\circ$C respectively. 3. All the parasitic eggs were degenerated about 4 months after filling drum tank with human excreta on 10th April while 10% of eggs were degenerated on 15th May, and all the eggs were degenerated about 4 months after filling cement tank on 24th August while about 10% were degenerated on 11th September and 20% on 4th October. 4. Degeneration rates of eggs were only 5~15% at 5cm below surface in the first tanks of three-compartment toilets while 45~65% at 50cm below, and concentration rates of eggs in second tanks were 8~12% of those in first tanks and only a few eggs were found in third tank but all of them were degenerated. Specific gravity of liquid of 1.022~1.024 in second tanks was not enough for overflowing eggs into third tanks.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.51-59
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• 2009

Bulb onion cultivation area has been restricted in southern part of Korea to avoid blotting and bulb division. The traditional culture method is transplanting bare-rooted plantlet into the field at the end of summer and harvesting at the beginning of next summer. The hot weather and weak plantlets occasionally causes unstable supply of onions in autumn. In order to enlarge cultivation area and to reduce culture period, long nursery system using plug tray and spring transplanting was tried. Forty cultivars collected from Korea and Japan were nursed using 200-plug tray and transplanted to the field in spring. Marketable yield was not related to the seedling size but lodging time. Cultivar of 'Hamasodachi' was lodged early and resulted low marketable yield. Cultivar of 'Cheonjudaego' was not lodged and yielded high but not in accordance with storability. Generally early lodged cultivars showed low storability. In order to avoid rainy harvesting season, cultivars requires excessive long time for lodging is not recommended for spring culture. Using plug nursery and spring transplanting, we successfully produced marketable onions in 3 months. But immediate using of the harvested onion is recommended. The storability of produced onions showed different result among cultivars, storage of spring onion was not recommended.

• Microbiology and Biotechnology Letters
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• v.40 no.3
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• pp.226-236
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• 2012

In the present work, the influence of prebiotic fructooligosaccharide (FOS) on adhesion to Caco-2 cells, viability, acid and bile tolerance, antibacterial, antioxidant, enzymatic, and metabolic activities of the probiotic starters Lactobacillus acidophilus GK20 and Lactobacillus paracasei GK74, has been explored. Experiments were conducted with fermented yoghurt over a period of 7 days at $4^{\circ}C$. When compared to control fermentations without prebiotic, the addition of FOS was seen to significantly (p<0.05) increase the viable cell counts of the probiotics, overall viscosity, and concurrently reduce the pH of the fermented yoghurts. Both Escherichia coli ATCC 11229 and Salmonella enteritidis ATCC 13076 were inhibited by the probiotics' antibacterial activities, while the synbiotic yoghurt containing mixed probiotics and FOS was noted to highly improve antagonistic action. When fermented with mixed starters, the addition of FOS (1.0%) resulted in the highest proteolytic ($1.06{\pm}0.06$ unit) and ${\beta}$-galactosidase activities ($20.14{\pm}0.31$ unit). However, FOS did not affect acid and bile tolerance, adhesion to Caco-2 cells or the antioxidant activity of the probiotics, although both L. acidophilus GK20 and L. paracasei GK74 had functionality as probiotic strains. Hence, a significant synbiotic effect was observed in fermented yoghurt after 7 days of storage at $4^{\circ}C$, and as a result, such synbiotic yoghurt can be said to possess synergistic actions which improve the gastrointestinal environment and promote of health.

• Journal of Biosystems Engineering
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• v.27 no.1
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• pp.59-66
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• 2002

The objectives of the study were to analyze the acoustic characteristics related to the internal quality factors of watermelon(Citrulus Vulgaris Schrad). Among the various internal quality factors, only four factors such as ripeness, inside cavity, yellow belt and blood flesh were considered in this study. Relationships between the internal quality factors, the day after fruit set and the day after harvest were also investigated. Test apparatus was the same as the apparatus described in the previous study(Choi et at., 2000). The selected sample was divided into four groups; 69 samples used for ripeness tests 56 samples for ripeness test along the day after fruit set and for yellow belt detection, 60 samples for ripeness along the day after harvest 44 samples fur blood flesh detection. It was shown that the first peak frequencies shifted to the lower range and the energy ratios of the bandwidths between 0∼550 Hz to the bandwidths between 850∼2500 Hz increased as the day after fruit set elapsed. Since the acoustic responses of the watermelon such as frequency and magnitude began to change from 10 days after harvest, the storage period of watermelon in a normal temperature condition seemed to be approximately 10 days after harvest. The ratios of the first peak amplitude to the maximum peak amplitude fur the sound watermelon showed the higher value than that fur watermelon with cavity inside, and the separation between the sound and cavity inside could be accomplished by the ratio value of 0.25. The energy ratios (0∼550 Hz/850∼2,500 Hz) for the watermelon with cavity inside showed the higher value than 2.3. The frequency characteristics of the yellow belt watermelon appeared mostly in the range of 600∼900 Hz frequencies. The yellow belt watermelon showing the energy spectral density function at this frequency range to be over 70 seemed to be not a marketable commodity, The energy ratios(0∼550 Hz/850∼2,500 Hz) for the blood flesh watermelon showed the higher value than 3.5.

• Journal of Korean Society of Transportation
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• v.20 no.7
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• pp.43-50
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• 2002

Competition to attract the increasing container cargoes of North China and the West Japan in North-East Asia region is fairly intensed in recent days between the main ports of Korea, China, and Japan. Inducing a new container cargo make those countries possible to invest enormous fund to mordernize its port facilities, as well as to improve efficiency in Port operation and management. In this situation, Strategy to attract transshipment cargoes is of the immediate necessity, This study, therefore, aims to establish the feasible strategies to attract transshipment container cargoes in the North-East Asian region by empirical analysis, he major output of the research is as follows : First, Busan Port to attract transshipment cargoes is required to adjust port tariff and free storage period with flexibility for liner shipping companies and freight forwarder. Second, Price-Demand function of Busan port between main competitive ports in North-East Asian region that is derived from strategies to attract transshipment cargoes, helps marketing manager to fix scientifically port price as understanding the change of demand quantity.