• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.2-4
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• 1998

Proliferation of Nocardia amarae cells in activated sludge has often been associated with the generation of nuisance foams. Despite intense research activities in recent years to examine the causes and control of Nocardia foaming in activated sludge, the foaming continued to persist throughout the activated sludge treatment plants in United States. In addition to causing various operational problems to treatment processes, the presence of Nocardia may have secondary effects on the fate of heavy metals that are not well known. For example, for treatment plants facing more stringent metal removal requirements, potential metal removal by Nocardia cells in foaming activated sludge would be a welcome secondary effect. In contrast, with new viosolid disposal regulations in place (Code o( Federal Regulation No. 503), higher concentration of metals in biosolids from foaming activated sludge could create management problems. The goal of this research was to investigate the metal sorption property of Nocardia amarae cells grown in batch reactors and in chemostat reactors. Specific surface area and metal sorption characteristics of N. amarae cells harvested at various growth stages were compared. Three metals examined in this study were copper, cadmium and nickel. Nocardia amarae strain (SRWTP isolate) used in this study was obtained from the University of California at Berkeley. The pure culture was grown in 4L batch reactor containing mineral salt medium with sodium acetate as the sole carbon source. In order to quantify the sorption of heavy metal ions to N amarae cell surfaces, cells from the batch reactor were harvested, washed, and suspended in 30mL centrifuge tubes. Metal sorption studies were conducted at pH 7.0 and ionlc strength of 10-2M. The sorption Isotherm showed that the cells harvested from the stationary and endogenous growth phase exhibited significantly higher metal sorption capacity than the cells from the exponential phase. The sequence of preferential uptake of metals by N. amarae cells was Cu>Cd>Ni. The specific surFace area of Nocardia cells was determined by a dye adsorption method. N.amarae cells growing at ewponential phase had significantly less specific surface area than that of stationary phase, indicating that the lower metal sorption capacity of Nocardia cells growing at exponential phase may be due to the lower specific surface area. The growth conditions of Nocardia cells in continuous culture affect their cell surface properties, thereby governing the adsorption capacity of heavy metal. The comparison of dye sorption isotherms for Nocardia cells growing at various growth rates revealed that the cell surface area increased with increasing sludge age, indicating that the cell surface area is highly dependent on the steady-state growth rate. The highest specific surface area of 199m21g was obtained from N.amarae cell harvested at 0.33 day-1 of growth rate. This result suggests that growth condition not only alters the structure of Nocardia cell wall but also affects the surface area, thus yielding more binding sites of metal removal. After reaching the steady-state condition at dilution rate, metal adsorption isotherms were used to determine the equilibrium distributions of metals between aqueous and Nocardia cell surfaces. The metal sorption capacity of Nocardia biomass harvested from 0.33 day-1 of growth rate was significantly higher than that of cells harvested from 0.5- and 1-day-1 operation, indicatng that N.amarae cells with a lower growth rate have higher sorpion capacity. This result was in close agreement with the trend observed from the batch study. To evaluate the effect of Nocardia cells on the metal binding capacity of activated sludge, specific surface area and metal sorption capacity of the mixture of Nocardia pure cultures and activated sludge biomass were determined by a series of batch experiments. The higher levels of Nocardia cells in the Nocardia-activated sludge samples resulted in the higher specific surface area, explaining the higher metal sorption sites by the mixed luquor samples containing greater amounts on Nocardia cells. The effect of Nocardia cells on the metal sorption capacity of activated sludge was evaluated by spiking an activated sludge sample with various amounts of pre culture Nocardia cells. The results of the Langmuir isotherm model fitted to the metal sorption by various mixtures of Nocardia and activated sludge indicated that the mixture containing higher Nocardia levels had higher metal adsorption capacity than the mixture containing lower Nocardia levels. At Nocardia levels above 100mg/g VSS, the metal sorption capacity of activate sludge increased proportionally with the amount of Noeardia cells present in the mixed liquor, indicating that the presence of Nocardia may increase the viosorption capacity of activated sludge.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.355-362
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• 1989

For the effective utilization of mackerel as a food sauce, the processing conditions of the frozen seasoned mackerel meat and the changes in taste compounds during its frozen storage were investigated. To prepare the frozen seasoned mackerel meat, the mackerel was headed, gutted manually, washed with tap water and deboned with the meat seperator. Then it was mixed with additives such as emulsion curd(32.1%, w/w), table salt(0.5%, w/w), sugar(2.0%, w/w), sodium bicarbonate(0.4%, w/w), polyphosphate(0.2%, w/w), monosodium glutamate(0.2%, w/w), onion powder(0.3%, w/w), garlic powder(0.1%, w/w), ginger powder(0.1%, w/w), soybean protein(3.0%, w/w) and sodium erythorbate(0.1%, w/w). This seasoned fish meat was frozen with contact freezer, packed In a carton box, and then stored at $-25^{\circ}C$. The moisture and lipid contents in the products were 70.8-71.7% and 10.9-11.3%, respectively. The taste compounds of the frozen seasoned mackerel meat were free amino acids(1625.0-1692.0mg/100g), nucleotides and their related compounds(316.6-366.8 mg/100g) as well as total creatinine(270.2-311.8 mg/100g), and small amount of betaine and TMAO. In free amino acids, the predominant ones were histidine, lysine, glutamic acid and arginine. It was supposed from the results that principal taste compounds of frozen seasoned mackerel meat were free amino acids, and that total creatinine, TMAO, TMA and betaine as well as nucleotides and their related compounds also played an assistant role.

• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.1-36
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• 2000

Periodic markets of the later Choson dynasty had undergone fundamental changes during the late Chosun dynasty and Japanese colony period. This paper aims to analyse the spatial distributions and changes of the periodic markets in the middle stream of Han-River in this era in the use of the survey of documentary records and fieldwork. Before the early 1910s, long distance transportation was made by riverboats, short distance transportation was done by porters and pack animals. Because goods such as rice, soybean and salt were very heavy and needed long distance transport, they were mainly transported by riverboats. Accordingly, riverports on the shore of river played important roles in exporting and importing goods as nodes of long distance transportation. The opening of railroad Seoul-Busan, the construction of new roads(Sinjakno) of 1910s and the use of oxcarts produced striking changes in the spatial distribution and hierarchy structure of periodic markets. These changes also had influence on the outflow and inflow of goods in the middle stream of Han-River. In the parr of outflow of goods, it seems that the line linking Icheon city-Yongin city-Anseong city played a role in making the boundaries of the marketing areas between goods trams ported by the rail road Seoul-Busan and goods done by Han River river boats. Anseong, Osan and Suwon periodic markets located around railroad stations occupied the higher positions than those of other regions in the hierarchial structure of periodic markets. Their marketing areas could nearly overwhelm those of riverports located in the middle stream region of Han River and extend to the middle stream region of Han River as a result of decrease of transport cost through using of oxcarts and railroads. the opening of railroad Suwon-Yeoju(Suryoson) and railroad Cheonan-Janghawon(Cheonjangson) brought about changes of the structure of long distance trade again. In a part of outflow of goods, it seems that as a result of the new opening of their railroads periodic markets around railroads seized a large portion of the marketing area of the southern part of Yoju and Ichon area and therefore made extreme change in rivershipping of Han River. In the inflow part of goods, goods transported by riverboats from the downstream of Han River before the opening of railroad were imported directly from railroad stations. Accordingly, rivershipping and riverports declined. And because goods were imported by way of great periodic markets and supplied to small periodic markets and consumers before the opening of railroad, but supplied from railroad stations to small periodic markets and consumers after the opening of railroad. The volume of turnover of such great periodic markets as Anseong, Osan and Suwon periodic markets therefore declined. On the other hand, because Yangpyong area had not been yet included within the sphere of influence of railroad until 1930s, it heavily depended on rivershipping of Han River as before. But the opening of railroad Seoul-Wonju(jungangson) brought about decline of rivershipping in Yangpyong and Wonju area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.550-556
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• 1985

In order to evaluate the marine mollusc muscle as foodstuff not only from the biochemical aspect but also from the view point of food science, we have analyzed the protein and amino acid compositions of the echiurid (Urechis unicinctus) and sea hare (Aplysia kurodai) muscle. The protein quality of the muscles was also investigated using in vitro methods based on in vitro digestibility, predicted digestibility, computed PER (C-PER) and discriminant computed PER(DC-PER). The remarkable feature of the protein compositions of the both muscles was that water soluble protein occupied a large amount of the muscle protein with fairly lower contents of the salt soluble protein. From the analysis of SDS-PAG electrophoresis, the sarcoplasmic proteins in the echiurid and the sea hare muscles were composed of 15 and 10 subunits, respectively. The free amino acid compositions of the total amino acids in the echiurid and sea hare muscle were characterized with $75\%$ of glycine and alanine, and with $78\%$ of taurine, respectively. The amino acid anaylsis of both muscle proteins showed that the echiurid muscle was rich in glycine, aspartic acid, glutamic acid, arginine and lysine, but was poor in cysteine, while the sea hare muscle was rich in glycine, glutamic acid, aspartic acid and arginine, but was negligible in cysteine and tryptophan. In the total amino acid profiles of the freeze dried muscles in echiurid and sea hare, there was not found a significant difference compared to the amino acid compositions of the muscle proteins. Predicting the protein quality of the echiurid and sea hare muscles using the in vitro method, it was apparently low compared to the muscle protein of fishes.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.216-224
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• 2018

To evaluate physiological effect of Aralia elata, in vitro antioxidant activity and hepatic protective effects were investigated. Ethyl acetate fraction from Aralia elata (EFAE) had higher total phenolic content than other fractions (n-hexane, chloroform, and distilled water layers). EFAE also showed significantly greater radical scavenging activity against 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH), than other fractions. Moreover, EFAE showed dose-dependent inhibitory effect of malondialdehyde (MDA). Hepatoprotective effects of EFAE against ethanol- and $H_2O_2$-induced oxidative stress and cytotoxicity in H4IIE and HepG2 hepatic cells were examined using 2',7'-dichlorofluorescein diacetate (DCF-DA) and 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay. The results showed that EFAE reduced cellular oxidative stress, and increased hepatic cell viability. In addition, EFAE inhibited ethanol-induced lipid accumulation in HepG2 cells. Finally, physiological substances of EFAE were analyzed using high performance liquid chromatography (HPLC), and the major bioactive compounds identified were 3,5-dicaffeoylquinic acid and chlorogenic acid.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.220-228
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• 2009

This study was conducted to determine the preblending effect of curing agents on the characteristics of mechanically deboned chicken meat (MDCM), including the pH, water-holding capacity (WHC), and stability under refrigeration conditions. MDCM was preblended with different curing agents [NaCl, 0.75 or 1.5%; sodium tripolyphosphate (STPP), 0.25 or 0.5%; ascorbic acid, 250 or 500 ppm; sodium nitrite, 75 or 150 ppm] and were stored at $4^{\circ}C$ overnight. The preblending of NaCl was found to have improved the WHC and emulsion stability; STPP was found to have improved the pH, WHC, and emulsion stability; and ascorbic acid or sodium nitrite did not affect the pH, WHC, and emulsion stability. The addition of ascorbic acid or sodium nitrite, however, decreased the 2-thiobarbituric acid (TBA) and volatile basic nitrogen (VBN) values of the preblended MDCM through the antioxidizing properties. The mixing effects of different curing agents on MDCM were also evaluated with nine different conditions. Among the treatments, the mixture of NaCl and STPP improved the WHC and emulsion stability due to the increased solubility of salt-soluble protein in the preblended MDCM. The mixture of NaCl, STPP, and ascorbic acid increased the pH, WHC, and emulsion stability, but the mixture of NaCl, STPP, ascorbic acid, and sodium nitrite improved the WHC, emulsion stability, and redness of the surface color with improved storage stability due to the decreased VBN and TBA values. As a result, the mixture of 1.5% NaCl, 0.5% STPP, 500 ppm ascorbic acid, and 75 ppm sodium nitrite showed the best properties as curing agents for MDCM preblending.

• Journal of Plant Biotechnology
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• v.38 no.2
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• pp.176-185
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• 2011

Rice is one of the most important crop in the world, in particular for food resources. With its small genome size of 383 Mb, the Oryza sativa is a model plant for genome research. Indeed, it's grain provides human with a source of carbohydrates and proteins. Rice grain has relatively low protein contents (around 8%) compared to other legume seeds (around 40%). Osborne classified seed proteins into water soluble albumin, salt soluble globulin, alcohol soluble prolamin and acidic/alkaline solution soluble glutelin. Glutelin and prolamin are the major storage proteins in rice. For the gene expression study of seed storage proteins, we analyzed 33,192 EST clones at immature stages in a rice cultivar (Oryza sativa L. cv. 'Ilpum'). Based on the expression analysis, we cloned 11 glutelin genes and figured out the 8 genes are located on Chromosome 2. The expression of glutelin genes appears to be about 28.2% of total level in immature seeds. Interestingly, glu-04 is duplicated as inverted sequences on the same chromosomes as far 4.5 kb. Our results indicate that glutelin genes, evolutionarily, were replicated on the chromosome and thus expressed as specific manners. In a whole protein composition analysis, glu05 (type B7) contains the highest lysin contents (4.51%) among the 11 rice glutelin genes. It will be an interesting future work to increase lysin contents by the gene overexpressor strategy with the aim of improved diet nutritionally fortified.

• Journal of the Korean Society of Food Culture
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• v.18 no.1
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• pp.56-68
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• 2003

The objects of this study are to find out (1) real situation of the food supply in prison under Imperial Government of Japan more cleary (historical meaning) and (2) which might help in understanding wrong present food consumption patterns in Korea which causes environmental as well as health problems. It is generally known that the length of the Japanese occupation for Korea is 36 years. However, it is concluded in this study that it was longer (70 years ; from 1875 to 1945 from when Japanese Army attacked and occupied Yungjongdo and Kanghwado island to e time when they were defeated on World War II.) Korea was annexed by Japan in 1910 then the Imperial Government of Japan dismissed the Korea Army, controlled the Office of Justice and the management of prison by force. Since then about 50% of all land was fell into Japanese Government ownership and 80% of Korean farmers became as tenant. After this change, Korea farmers were forced to pay extremely high rent (up to 80% of its harvest). Forced immigration, low price procurement of grain by Japanese government up to more than 30%of their production, was practiced. Accordingly, the food situation of Korean farmers became miserable, which may caused more violations of Imperial Japanese Law. Malnutrition, epidemic diseases, mortality rate of infants soared and average life expectancy shortened to 20-30 years old. This was the period of World Economic Crises and Food Crises in Japan. It was said then that if one Japanese comes to Korea then 200 Koreans will starved to death. Meanwhile, Proconsul Bureau of Chosun requested to the Department of Medicine, the Imperial University of Kyungsung to survey food supply situation of Koreans in prison throughout Korea. Objectives of the survey then was not only to find out scientifically whether it is agreeable in maintaining prisoner's health and also find out the possibility to save food during food crisis. Survey was started from 1923 and ended in 1945, and it focussed on prisoners in the Seodaemoon Prison. This report is the outcome of the first survey. They concluded that the food supplied was nutritionally (had) no problem, in compare with those of workers in the factory, students in the dormitory in Japan and with those of prisoners in Taiwan, France and Germany. Amount of grain supplied were different according to their work lord and was divided into 9 different levels. Total grain was consisted of 50% millet, 30% soybean and 20% indica rice(variety). However, there were no difference in the amount of supply of side dishes between work groups. For the highest working group, 3280g of boiled grain per day was supplied to make stomach full but as a side dishes, salty fermented bean paste, fermented fish and salty soups, etc. was supplied. Deficiency of animal protein were observed, however, high intake of soybean may possibly caused animal protein deficiency problem. On the contrary, the intake of water soluble vitamins were insufficient but the level of calcium and iron intake seems to be sufficient, however, imbalance of intake of nutrition may caused low absorbtion rate which might caused malnutrition. High intake of dietary fiber and low intake of cholesterol may possibly prohibited them from so called modem disease but may caused the defect in disease resistancy againist epidemics and other traditional disease. Over intake of salt(20-30g per day) was observed. Surveyors who attended in this survey, mentioned that the amount of food intake may nutritionally be sufficient enough but the quality of food(and possibly, the taste of food) were like that of animal feed. For the officials who received this report might consider that considering the war situation and food crisis, the supply situation of food in the prison may considered to be good enough(because they are not starving). But as a Korean who studied this report, one feel extremely pity about those situation because (situation of) those period were very harsh under the Imperial Law and keeping the Law by Koreans were almost impossible, therefore, about one third adult violated the Law and were put into jail. And they were treated like animals.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.55-67
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• 2012

We compared the general composition of Mozzarella cheese manufactured by the traditional method and by an ultrafiltration technique. The comparison of the general components between raw milk and the retentate of ultrafiltration (CF 2 and CF 3) demonstrated the following. The fat, protein, and non-fat solid contents of the retentate were higher than those of raw milk, but the lactose content was lower. The effect of 3 factors-fat content (0.5% and 3%), bacterial populations (30,000 CFU/mL and 100,000 CFU/mL), and ratio of added starter and rennet (50, 65, or 80)-on Mozzarella cheese made by the traditional method and made using the retentate of ultrafiltration (CF 2 and CF 3) were compared. Total solids (TS), fat, lactose, total nitrogen (TN), water soluble nitrogen (WSN), non-protein nitrogen (NPN), and salt (NaCl) were affected by fat content, bacterial population, and the ratio of starter and rennet added, but the ash content was not affected. During storage at $4^{\circ}C$ over a period of 3 months, the TS, WSN, NPN, and NaCl contents increased significantly (p<0.05), but fat, lactose, and TN contents decreased significantly (p<0.05), while ash contents remained constant. In whey, the protein, lactose, and solids not fat contents were higher in cheese made from ultrafiltration retentate than in traditional Mozzarella cheese. These results indicate that ultrafiltration can be applied to producing several Mozzarella-type cheeses in order to meet consumer needs.

• Journal of fish pathology
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• v.29 no.1
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• pp.35-43
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• 2016

In comparison to the numbers of such studies of fish, few studies have been carried out on the immunity, physiology and ecology of abalone, while studies on abalone disease are also extremely rare. Moreover, mass mortality of cultured abalone due to pathogenic bacteria has not been reported in the southern coast of Korea. However, Vibrio-like bacteria have been isolated from dead abalone, which indicates that a review is required in order to determine the cause of abalone mortality. Use of an antimicrobial agent to minimize the damage caused by disease in abalone farms is common, but the therapeutic effects are insignificant. Demand for probiotics has increased, but research on the development of probiotics for use in abalone culture is very rare. Therefore, the present study isolated KC16-2 from fermented kimchi soup and investigated the characteristics of the isolate as a candidate probiotic bacterium in abalone. KC16-2 was identified as Bacillus amyloliquefaciens (B. amyloliquefaciens KC16-2) based on its biochemical properties and 16S rRNA gene sequence. B. amyloliquefaciens KC16-2 showed inhibitory effects against the growth of various vibrios in vitro, and kept the numbers constant until four days after inoculation in marine water at a temperature of $15{\sim}25^{\circ}C$, indicating the possible use of KC16-2 as a probiotic, except in the winter. The growth of KC16-2 was inhibited by bile salt, but the numbers increased over time suggesting the bacteria were still alive in the abalone's digestive tract. Abalone fed with a diet including KC16-2 for 12 weeks showed good growth, but showed no significant differences from the control group. However, the mortality of the abalone supplied the probiotic diet was reduced to half that of the control group in a challenge test with Vibrio tubiashii. Therefore, we suggest that B. amyloliquefaciens KC16-2 could be used as a probiotic bacterium for control of the mortality of abalone caused by opportunistic pathogenic vibrios.