• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.35-39
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• 1987

The present study was attempted to obtain the basic data concerning a reasonable preparing method and the optimum fermentation conditions of Kochujang (Red pepper paste). To establish the standard qualify of Kochujang, changes of the chemical composition and the numbers of bacteria and feasts in Kochujang during fermentation were observed. Moisture, salts and crude ash contents of Kochujang were not changed significantly during fermentation. Titrable acidity and amino nitrogen gradually increased with the time-passed, whereas crude fat gradually decreased with the time-elapsed. And reducing sugar and total nitrogen increased until 40 days, but slightly decreased after this period. The numbers of bacteria and yeasts in the ingrients for the preparation of Kochujang were $3.9{\times}10^7/g$, $1.5{\times}10^3/g$ in red pepper powder, $7.6{\times}10^4/g$, $2.8{\times}10^2/g$ in salts. respectively, but those of sugar and malt were not more than 100/g. Microbial counts in Kochujang during fermentation increased until 40 days, but those are gradually decreased after that.

• Ocean and Polar Research
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• v.26 no.4
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• pp.581-594
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• 2004

CREAHS II carried out an intensive hydrographic survey covering almost entire East Sea in 1999. Hydrographic data from total 203 stations were released to public on the internee. This paper summarized the results of water mass analysis by OHP (Optimum Multiparameter) method that utilizes temperature, salinity, dissolved oxygen, pH, alkalinity, silicate, nitrate, phosphate and location data as an input data-matrix. A total of eight source water types are identified in the East Sea: four in surface waters(North Korea Surface Water, Tatar Surface Cold Water, East Korean Coastal Water, Modified Tsushima Surface Water), two intermediate water types (Tsushima Middle Water, Liman Cold Water), two deep water types (East Sea Intermediate Water, East Sea Proper Water). Of these NKSW, MTSW and TSCW are the newly reported as the source water type. Distribution of each water types reveals several few interesting hydrographic features. A few noteworthy are summarized as follows: The Tsushima Warm Current enter the East Sea as three branches; East Korea Coastal Water propagates north along the coast around $38^{\circ}N$ then turns to northeastward to $42^{\circ}N$ and moves eastward. Cold waters of northern origin move southward along the coast at the subsurface, which existence the existence of a circulation cell at the intermediate depth of the East Sea. The estimated volume of each water types inferred from the OMP results show that the deep waters (ESIW + ESPW) fill up ca. 90% of the East Sea basins. Consequently the formation and circulation of deep waters are the key factors controlling environmental condition of the East Sea.

• The Korean Journal of Mycology
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• v.5 no.1
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• pp.13-19
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• 1977

In order to investigate histopathologically the nature of varietal resistance and infection process of the rice bast fungus, Pyricularia oryzae. this experiment was undertaken by using the resistant cultivar Tongil and susceptible cultivars Norin No.6 and Jinheung in 1973 to 1974. 1) It was found that appressorium of the fungus forms not only at 4 hours after incubation under the favorable conditions but also peak of appressorial formation is at 48 hours treatment. Physical stimulus known to be a definite factor for appressorial formation. The optimum temperature range for appressorial infection was at $24^{\circ}C$ to $28^{\circ}C$, and pH was between 4.8 to 8.0 with 6.8 as the optimum. 2) Although percent of appressorial formation on the leaves of resistant Tongil and susceptiible Norin No.6 were only slightly different, there was a remarkable difference between resistant and susceptible cultivars with regard to percent of hyphal infection and index for hyphal extension. Index of hyphal extension was 1.6-2.7 in Tonyil. while in susceptible cultivar was 3.4-6.6. The rate of discoloration of infected cells, a indication of hypersensitivity, was greater in the resistant than in susceptible cultvar. 3) Therefore, it could be concluded that resistance of Tongil cultivar may be attributable to a higher degree of mechanical barriers as well as a higher level of antifungal substance accumulation.

• Food Science and Preservation
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• v.19 no.6
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• pp.799-806
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• 2012

This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.68-75
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• 2008

The aim of this study was to evaluate the quality characteristics and antioxidant activity of yogurt containing spirulina. Yogurt base was prepared from skim milk added with $0.25{\sim}1%(w/v)$ spirulina powder and fermented with lactic acid bacteria (S. thermophilus : L. bulgaricus = 1 : 1) at $40^{\circ}C$ for 12 hr. Kiwi puree and oligosaccharides were then added. The addition of 1% spirulina powder stimulated the growth of lactic acid bacteria, which showed the highest viable cell count ($3.4{\times}10^9$ CFU/mL), and increased the titratable acidity (1.10%). The viscosity range of the yogurt was 6,000 to 9,000 cP, and the sugar content of the yogurt was around 18 $^{\circ}Brix$. The antioxidant activities were determined using the DPPH method, and the hydroxyl radical scavenging activity of the yogurt containing spirulina was higher than that of the control. The sensory evaluation scores for appearance, odor, taste, overall acceptability and buying intention were higher in the yogurt containing 0.25% spirulina than in the other groups. The amount of macronutrients in the yogurt containing spirulina was higher than that in the control. In addition, the amounts of micronutrients in the yogurt containing spirulina was significantly increased. According to these results, the optimum concentration of spirulina powder is around 0.25%.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.392-399
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• 2013

This study aimed to investigate responses of photosynthesis, plant growth, and phytochemical contents to different artificial light sources for 'Seneca RZ' and 'Gaugin RZ' two butterhead lettuce (Lactuca sativa L.). In this study, fluorescent lamps (FL), three colors LEDs (red, blue and white, 5 : 4 : 1; RBW) and metalhalide lamps (MH) were used as artificial lighting sources. Photoperiod, air temperature, relative humidity, EC, and pH in a cultivation system were maintained at 16/8 h, $25/15^{\circ}C$, 60~70%, $1.4{\pm}0.2dS{\cdot}m^{-1}$, and $6.0{\pm}0.5$, respectively. The photosynthetic rate of both two butterhead lettuce were the highest under RBW in middle growth stage. However, in late growth stage, the photosynthetic rate of both two butterhead lettuce were higher under RBW and MH than FL. The light sources showed significant results for plant growth but those effects were different to variety. Fresh and dry weight of 'Gaugin RZ' butterhead lettuce under MH were heavier than other lights in all growth stages. Growth of 'Seneca RZ' butterhead lettuce was maximized highest under MH in middle growth stage and FL in late growth stage. In the leaf tissue of 'Seneca RZ' butterhead lettuce, tipburn symptom occurred under all light sources and in the leaf tissue of 'Gaugin RZ' butterhead lettuce, it occurred under two light sources except for fluorescent lamps in late growth stage. kinds of lamp affect plant growth more than plant quality. Relative growth rate of both two butterhead lettuce was faster in middle growth stage than late stage. Growth of 'Gaugin RZ' was shown by kinds of lamp in middle growth stage and but it was not significantly affected by light sources and variety in late stage. Most of the phytochemical contents of two butterhead lettuce were significantly affected by different light sources. Contents of all vitamins showed higher than other light sources on RBW for both two lettuce, especially ${\beta}$-Carotene content of 'Gaugin RZ' was the highest. Plant growth, photosynthesis, and phytochemical contents were observed significant effects by different light sources for two butterhead lettuce but those effects were highly different between variety and kinds of phytochemicals. Therefore, the selection of optimum light source should be considered by variety and kinds of phytochemicals in the plant factory.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.263-268
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• 2002

Bacillus polyfermenticus SCD, which is commonly called a 'Bisroot' strain, has been appropriately used for the treatment of long-term intestinal disorders, since the live strains, in the form of active endospores, can successfully reach the target intestine. Goal of this study was to develop an industrial medium for growth and sporulation of B. polyfermenticus SCD. From the results of effect of mixed carbon sources on growth and sporulation of B. polyfermenticus SCD, glucose 2% and starch 2% was particularly found to be the most effective for the maximum number of spore production, resulting in spore cells of $4.3{\times}10^9\;spores/mL$ with a sporulation yield of 91%. For the effect of nitrogen sources, the maximum spore cells of $5.7{\times}10^9\;spores/mL$ of B. polyfermenticus SCD with a sporulation yield of 97% was obtained when B. polyfermenticus SCD was cultivated in an optimum nitrogen source medium containing 5% soybean flour. A medium involving proper phosphate salt yielded the maximum number of a spore cells of $6.0{\times}10^9\;spores/mL$ with a sporulation yield of 95%. Finally, the efficacy of an industrial medium (KH5 medium) on growth and sporulation of B. polyfermenticus SCD was investigated in jar fermenter. The higher number of viable cells $(3.3{\times}10^{10}\;cells/mL)$ and spore cells $(3.0{\times}10^{10}\;spores/mL)$ were obtained in 5 L fermenter when compared with a 500 mL baffle flask cultivation. Thus, KH5 medium developed in this study shows promise as an industrial medium because of higher cells and sporulation yield.

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.151-159
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• 1989

The present study has been designed to define the effects of photosynthetically active radiation, leaf temperature, and water stress on photosynthesis and respiration of leaves of four oak species (Quercus mongolica, Quercus aliens, Quercus variabilis, and Quercus serrate). The results obtained are as follows : 1. The estimated light compensation points at which Pn approached zero were 38, 24, 20, and $18{\mu}Em^{-2}s^{-1}$ for Q. aliens, Q. variabilis, Q, mongolica, and Q. serrate, respectively. The light saturation points occurred at $500{\mu}Em^{-2}s^{-1}$ in three oak species except Q, aliens. 2. The maximum rates of Pn were 19.7, 15.2, 11.2, and 11.0 mg $CO_2$ $dm^{-2}h^{-1}$ for Q. variabilis, Q. serrate, Q. monglica, and Q. aliens leaves, respectively. 3. The transpiration rates of Q. variabilis and Q. serrate leaves were slightly higher than those of Q. mongolica and Q. aliens leaves at various photosynthetically active radiations(PAR), but cuticular transpiration rates at dark were similar in four oak species. 4. The optimum photosynthesis occurred at $25^{\circ}C$ in Q. aliens, Q. variabilis, and Q. serrate leaves, but $20^{\circ}C$ in Q. mongolica leaves. In four oak species, the net photosynthesis approached zero at about $40^{\circ}C$. 5. The dark respiration rates of leaves exhibited the following ranking of species : Q, variabilis > Q. mongolica > Q. aliens > Q. serrate. 6. The maximum productive efficiency (Pg/Rd) of leaves occurred highest in Q, serrate at $20^{\circ}C$, then in Q. mongolica at $20^{\circ}C$, then in Q, aliens at $25^{\circ}C$, and finally in Q. variabilis at $15^{\circ}C$. 7. The decrease of net photosynthesis in Q. serrate began at about -1.2 MPa, and then approached zero at -2.9 MPa of leaf water potential. The decrease of net photosynthesis began at 3% of water loss, and then approached zero at 17.5% of water loss. 8. As indicated by tissue-water relations parameters, it may be suggested that Q. aliens and Q. variabilis are more tolerant and favored on xeric forest soils than Q. mongolica and Q. serrate.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.235-240
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• 2012

This study was conducted to find out the optimum cropping system for the stable production of forage crops in the newly reclaimed land located at Gwanghwal region of Saemangum reclaimed land in which the soil is sandy loam (Munpo series). There were two treatments of nitrogen fertilization 20% increment based on the standard fertilization of 150, $200kg\;ha^{-1}$. Whole crop barley as the winter crop sowed on 27 October. After the whole crop barley was harvested at the end of May. Corn and sorghum${\times}$sudangrass as the summer crop sowed at the early of June successively on the same field. Emergence rate the whole crop barley was high while the summer crops were low. Soil salinity was increased during cultivation of summer crops. However, corn and sorghum${\times}$sudangrass were not damaged by salt. Increase of nitrogen fertilization made the growth of cultivation crops good, stem and leaf tended to have a lot of the mineral nutrients at heading stage and silking stage. After experiment, among soil chemical properties pH, content of exchangeable sodium were decreased and content of organic matter, available phosphate were increased. Dry matter yield were showed whole crop barley $13,170kg\;ha^{-1}$ and sorghum${\times}$sudangrass $19,440kg\;ha^{-1}$ by increment of nitrogen fertilization. Therefore, to improve the product and nutrient balance of reclaimed saline land comprehensive soil management should be considered.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.385-392
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• 2012

This study was conducted to find out the optimum cropping system for the stable production of forage crops in the newly reclaimed land located at Gwanghwal and Gyehwa region of Saemangum reclaimed tide land from October, 2009 to October, 2011. Whole crop barley (WCB), Rye, Italyan-ryegrass (IRG) as winter crops and Corn, Sorghum${\times}$sudangrass hybrid (SSH) as summer crops were cultivated. Soil chemical properties, nutrient uptake, feed value, growth and yield were examinated. The testing soil was showed saline alkali soil where the contents of organic matter, available phosphate and exchangeable calcium were very low, while exchangeable sodium and magnesium were higher. Changes of soil salinity during the growing season of forage crops were less than 0.2%, and the growth of forage crops was not affected by salt injury. Standing rates of winter crops were higher in the order of Rye, WCB, and IRG, while the dry matter yield of winter crops was higher in the order of IRG, Rye and WCB. The highest crude protein (CP) content was recorded in IRG, and total digestive nutrients (TDN) contents were increased in the order of WCB, IRG, and Rye. The TDN content was higher in corn, whereas other feed value was higher in SSH. The content of mineral nutrients on stem, leaf and grain in IRG, Corn were high. After experiment pH was lowed, contents of exchangeable magnesium, sodium and organic matter were decreased while contents of total nitrogen, available phosphate and exchangeable potassium, calcium were increased. Winer crops and summer crops after continually cultivating in cropping system, fresh matter yield increased, compared to WCB-Corn (74,740 kg $ha^{-1}$), IRG-SSH 10%, IRG-Corn 7%, Rye-SSH 6%, Rye-Corn and WCB-SSH 3%. Dry matter yield increased, compared to WCB-Corn (20,280 kg $ha^{-1}$), IRG-SSH 7%, Rye-SSH 6%, IRG-Corn/Rye-Corn/WCB-SSH 3%. The TDN yield increased, compared to WCB-Corn (13,830 kg $ha^{-1}$), IRG-SSH 2%, WCB-SSH and IRG-Corn 1%. Therefore, we suggest that the crop combination of IRG-SSH and WCB-SSH would be preferred for silage stable production.