• Ocean and Polar Research
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• v.29 no.4
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• pp.401-410
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• 2007

In Korea the study of marine heterotrophic protists started in the late 1980s, and since the early 1990s many studies have been conducted in various marine environments. In this article, studies on the distribution and abundance of protists and the biotic interactions(bacteria-protists, phytoplankton-protists) conducted in Korean coastal waters are reviewed, and a field study is reported and discussed. The field study in Masan Bay was carried out from February 2004 to November 2005 at seven selected stations representative of the bay. During the study, the mean abundance of heterotrophic bacteria and the mean concentration of chlorophyll-a were $2.1{\times}10^6\;cells\;mL^{-1}$ and $9.8{\mu}g\;L^{-1}$, respectively. Heterotrophic protists consisted of heterotrophic dinoflagellates, heterotrophic nanoflagellates(excluding dinoflagellates) and ciliates, and their abundances were means of $7.9{\times}10^4\;cells\;L^{-1}$, $1.2[\times}10^3\;cells\;mL^{-1}$, and $4.0{\times}10^4\;cells\;L^{-1}$, respectively. Generally, the chlorophyll-a concentra+CZ14tions and the abundances of heterotrophic bacteria and protists were higher in the inner zone of the bay, where there are high concentrations of organic matters, than in the middle and outer zones. Using the grazing rates of heterotrophic nanoflagellates on bacteria previously reported in this area, it can be calculated that about 69% of bacterial producton was removed by HNF grazing activity. About 24% of initial chlorophyll-a concentration was removed by microzooplankton grazing activity. In conclusion, this study suggests that in Masan Bay heterotrophic protists control the growth of bacteria and phytoplankton, and heterotrophic protists represent an important link of bacterial & microalgal biomass to higher trophic levels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.703-709
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• 2001

To compare the hypolipidemic effects of perilla oil with different kinds of dietary fat and oil forty eight 20 days old male Wistar rats were fed one of the following diets for 4 weeks: basal diet for control containing 9.4 w/w% corn oil(CO), 9.4 w/w% beef tallow (BO), 9.4 w/w% perilla oil(PO) and 4.7 w/w% beef tallow plus 4.7% perilla oil(BP). The amount of diet consumed and body weight gain rate were not significantly different among the four dietary groups. The levels of plasma triglyceride and total cholesterol in PO group were significantly lower than those of BO and BP groups. PO group also had significantly lower LDL-cholesterol in BP group were than other groups. The levels of plasma triglyceride tatal-cholesterol and LDL-cholesterol in BP group were significantly lower than those in BO group by 9.2%, 10.3% and 18.6% respectively. Plasma glutamic oxaloacetic transferase and alkaline phosphatase activities and uric acid levels in PO group were significantly higher than other groups and were somewhat beyond the normal levels. These findings showed that perilla oil with hypolicpidemic effects could have some adverse effects on hepatic and other organic functions in rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.605-610
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• 2001

To suppress the gas forming caused by some yeast in the pack of traditional kochujang prepared at Sunchang area, which is the most severe problem during distribution of commercial products, mustard or horseradish powder as natural preservatives was mixed to the ingredients of kochujang and left for fermentation in clay pot as commercial scale for 180 day. The composition changes including quality and gas formaing in the kochujang containing those additives were monitored physicochemically and organoleptically. The fermented kochujang containing those additives were monitored physicohemically and organoleptically. The fermented kochujang containing 0.6% of horseradish showed lower organic acid content than that of the control but amino type nitrogen content, which is one of the important quality reference of kochujang, was higher in the one containing 0.6% natural preservatives. No color changed in the kochujang containing mustard but L and a value were increased in the kochujang containing horseradish. No difference of free reducing sugars was showed by the addition of those natural preservatives and the addition of 0.6% horseradish to kochujang had completely stopped gas forming during fermentation. The overall quality of the kochujang containing 0.6% horseradish was superior than that of the other treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.204-210
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• 2002

The quality characteristics and sensory evaluation of chungkookjang were investigated. The samples were prepared and fermented by the inoculation of Bacillus strains; B. subtilis, B. natto and B. licheniformis as a single starter, and mixed culture of B. natto and B. licheniformis on the industrialized model system. It was shown that microbial growth, protease activity, contents of amino-and ammonia-nitrogen and contents of organic acid were higher in B. subtilis inoculated sample, and were lower in B. licheniformis inoculated one. General quality characteristics of sample inoculated by mixed culture of B. natto and B. licheniformis took a middle position between each B. natto and B. licheniformis inoculated one. Fifty eight species of odor components were identified. Ethanol, 3-methyl-1-butanol, acetic acid, benzaldehyde and alkyl pyrazines were identified in all samples and most of other flavor components were strain specific. The contents of unpleasant smell components, alkyl pyrazines and benzaldehyde, were lower in B. licheniformis inoculated sample. The sensory evaluations showed that chungkookjang manufactured from mixed culture of B. natto and B.licheniformis was most acceptable. Therefore, results indicated that chungkookjang manufactured from mixed culture of B. natto and B. licheniformis induced better sensory quality than that of the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.277-283
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• 2002

In the present study, adverse effects of megadose of dietary perilla oil were investigated in an experimental model consisted of 6 groups of Wistar rats. To compare the adverse effects of megadose perilla oil with different kind of dietary fat, rats were fed one of the following diets for one month: 10% beef tallow (B$_1$B), 10% corn oil (C$_1$B), 10% perilla oil (P$_1$B), 20% beef tallow (B$_2$B), 20% corn oil (C$_2$B), and 20% perilla oil (P$_2$B) diet. The body weight gain rate seemed to be more affected by the size of fat contents than the species of fat in the diet, so the body weight gain rate of 20% fat groups were significantly higher than those of 10% fat groups in spite of the larger amount of flood intake in 10% fat groups than in 20% fat groups. The levers of plasma triglyceride and total-cholesterol in 20% fat groups were significantly increased in dose dependent fashion when compared to 10% groups, the values of beef tallow (B$_2$B) group being the highest among all groups. Plasma glutainic pyruvic transferase activities and level of blood urea nitrogen had a tendency to increase along with increase of fat contents (%) in diets, the values of P$_2$B group, the highest among all groups, being beyond the normal levers. The plasma carbon dioxide concentration of P$_2$B group was the highest in all groups and exceeded the normal value, there being no significant difference among the plasma carbon dioxide concentration of others groups. The results showed that large dose and long term intake of dietary perilla oil had some adverse effects on hepatic and other organic functions in rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.115-118
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• 2003

This study was conducted to determine optimal extraction condition and free radical scavenging effect of ethanol extracts of Campell Early grape seeds and skins at different temperatures, and of organic solvent fractionated from ethanol extracts of grape seeds and skins. The free radical scavenging effect was tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and expressed as dose required for a 50% reduction of DPPH radical (RC$_{50}$). The extraction yields were increased with increasing the extraction temperature but it was not related with ethanol concentrations. The ethanol extract of grape seeds obtained at 5$0^{\circ}C$ showed the more stronger RC$_{50}$ (16.8 $\mu\textrm{g}$/mL) than those of both 3$0^{\circ}C$ and 78$^{\circ}C$. The ethylacetate fraction obtained from ethanol extract of grape seed showed the strongest RC$_{50}$ (15.4 $\mu\textrm{g}$/mL). Overall, both ethanol extracts and their fractions of grape seeds showed significantly stronger free radical scavenging effect than those of skin extracts.racts.

• Journal of Agricultural Extension & Community Development
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• v.16 no.2
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• pp.363-384
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• 2009

This study aimed at finding directions for Korean agriculture to establish a new paradigm of sustainable development. Various problematic issues and concerns in the environment necessitate the transformation of Korea's development paradigm from unconditional growth to "Green Growth" through new policies on green value and review of various advanced researches. In this research, the environment-friendly agriculture's problems, particularly in agribusiness were analyzed. Drawing from Michael Porter's Value Chain Analysis, this research developed a value chain model in agriculture that reflects the environment and the present situations. Future directions in the agriculture sector were also discussed. Korea realized food self-sufficiency through the green revolution in the early 1970s. However, a lot of problems have also occurred, including ground and water pollution and the destruction of ecosystems as a result of the overuse of pesticides and chemical fertilizers. In the late 1970s, the growing interest on environment-friendly agriculture led to the introduction of sustainable methods and techniques. Unfortunately however, these were not innovative enough to foster environment-friendly agriculture. Thereafter, the consumers' distrust on agricultural products has worsened and concerns about health have increased. In view of this, the Ministry of Food, Agriculture, Forestry and Fisheries introduced in December 1993 a system of Quality-Certified Products for organic and pesticide-free agri-foods. Although a fundamental step toward the sustainability of the global environment, this system was not enough to promote environment-friendly agriculture. In 2008, Korea's vision is for "Low Carbon Green Growth" to move forward while also coping with climate change. But primary sectors in a typical value chain do not consider the green value of their operations nor look at production from an environmental perspective. In order to attain sustainable development, there is a need to use less resources and energy than what is presently used in Korean agricultural and value production. The typical value chain should be transformed into a "closed-loop" such that the beginning and the end of the chain are linked together. Such structure allows the flow of materials, products and even wastes among participants in the chain in a sustained cycle. This may result in a zero-waste sustainable production without destroying the ecosystem.

• Food Science and Preservation
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• v.8 no.1
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• pp.79-85
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• 2001

To study the availability of the Atractylodes japonica Koidz. as ingredients for functional flood, the properties of chemical components were investigated and the results were followed. Among general components of Korean A. japonica, total sugars portions from fresh and dried samples took 31.3% and 46.8%, respectively. Mineral contents were K 4,038.9 ppm, P 1,698.5 ppm, Ca 731.8 ppm, Mg 477.1 ppm, Na 87.2 ppm, Fe 56.4 ppm, Zn 22.4 ppm and Mn 13.5 ppm in fresh sample, and K 8,738.9 ppm, P 3,511.6 ppm, Ca 966.1 ppm, Mg 912.8 ppm, Na 147.4 ppm, Fe 113.9 ppm, Zn 46.7 ppm and Mn 23.5 ppm in dried sample. Sucrose in Korean A. japonica was 0.88% in fresh sample and 3.44% in dried sample, and it was main component of sugar. The largest amount of organic acid in Korean A. japonica was tartaric acid, which was 3,849.0 mg% in fresh sample main and 5,305.5 mg% in dried sample. The main amino acid of total amino acids in fresh and dried samples were arginine 291.3 mg% and proline 567.8 mg%, respectively. The main fatty acid of fresh and dried samples were behenic acid 4.0% and linoleic acid 17.99%, respectively. The most distinctive volatile flavor compound was furanodiene which took 17.91% in flash and 40.69% in dried Korean A. japonica.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1612-1617
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• 2009

Aspergillus sp. 101 was isolated from the Korean traditional soybean paste for the production of a salt-tolerant protease. The optimal condition for the production of a salt-tolerant protease was determined with various energy sources such as carbon, nitrogen, and protein, and at different culture conditions such as temperature, pH, incubation time and NaCl concentration. The most favorable organic nitrogen sources were 2% defatted soybean flour (DSF) and soy protein isolate (SPI). Optimal pH and temperature were pH 6.0 and $25{\sim}27^{\circ}C$, respectively. Therefore, Aspergillus sp. 101 protease was a mild acid (or neutral) protease. Protease production was the highest at 0.1% concentration of $CaCO_3,\;K_2HPO_4$ and Arabicgum. Aspergillus sp. 101 could grow in culture medium at 15% NaCl concentration and produce a salt-tolerant protease even at 7% NaCl. The cell mass and protease activity of Aspergillus sp. 101 cultured in a modified medium was comparatively higher in Czapek dox and protease producing media. Hence, Aspergillus sp. 101 protease can be utilized in soy or fish sauce industry as a salt-tolerant protease starter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1484-1490
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• 2006

This study was carried out to prepare spaghetti sauce with adductor muscle of pearl oyster (SSAM) and to compare with commercial spaghetti sauce (CSS). From the results of organic acid, pH, hunter color value and sensory evaluation, the optimal addition ratio of adductor muscle of pearl oyster was 11% based for preparing SSAM and reasonable $F_0$ value was about 4 min for keeping storage of SSAM. The proximate composition of SSAM was 69.8% for moisture, 3.7% for protein, 4.2% for crude lipid and 3.4% for crude ash. SSAM was superior in sensory flavor and texture to CSS. There was, however, no significant difference (p<0.05) in sensory color between CSS and SSAM. The total amino acid content (3,033.4 mg/100 g) of SSAM was higher than that (2,305.7 mg/100 g) of CSS and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Calcium and phosphorus contents in SSAM were 48.5 mg/100 g and 27.1 mg/100 g, respectively. Calcium level based on phosphorous was 1.78, which was a good ratio for absorbing calcium. The free amino acid content and taste value of SSAM were 989.4 mg/100 g and 141.04 mg/100 g, respectively These results suggested that the major taste active compounds among free amino acid were glutamic acid and aspartic acid.