• Applied Biological Chemistry
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• v.47 no.1
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• pp.78-84
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• 2004

In order Nuruk to improve the quality of millet wine, a traditional Jeju cereal wine, yeasts and molds were isolated from 35 kinds of Nuruk collected nationwide. Isolated strains were screened for saccharification of starch and brewing of millet wine. Fermentation characteristics of millet wine with different types of Nuruk were also investigated. The average number of microbial populations in the Nuruk were $6.4{\times}10^5{\sim}4.5{\times}10^7\;cfu/g$ for molds and $1.4{\times}10^4{\sim}7.7{\times}10^7\;cfu/g$ for yeasts. Among the 169 strains of molds and 103 strains of yeasts, 16 strains were screened for saccharifying activity on starch as a substrate, and one yeast strain was screened for the brewing of millet wine. A8-3, supposed as Aspergillus sp., showed the highest enzyme activities of glucdamylase, ${\alpha}-amylase$ and xylanase while B23-3 strain, supposed as Rhizopus sp., showed the highest saccharifying activity. A10-4, supposed as Saccharomyces sp., showed the highest level of weight loss from $CO_2$ evolution, sugar and alcohol tolerance during fermentation. When the Nuruk was made after inoculation with the selected strains, saccharifying activity was higher for the co-cultivation of A8-3 and B23-3 than individual cultivation of each strain. Similar saccharifying activities were shown in both disc-type and pellet-type Nuruk. It was suggested that pellet-type Nuruk could improve fermentation yield. The collected Nuruk consisted of $10{\sim}13%$ moisture, $55{\sim}70%$ total sugar, $10{\sim}18%$ crude protein, $0.2{\sim}1.0%$ crude fat and $1.8{\sim}2.1%$ ash. The Nuruk made in this study was composed of $12{\sim}15%$ moisture, $61{\sim}71%$ total sugar, $15{\sim}20%$ crude protein, $0.4{\sim}1.5%$ crude fat and $1.1{\sim}1.5%$ ash.

• Journal of Aquaculture
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• v.1 no.1
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• pp.85-102
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• 1988

An experimental study on seedling production and wintering to develop pearl oyster, Pinctada fucata culture in Korea was carried out. from December 1986 to November 1988 in waters of Kori and of Seogwipo as wintering and of Eogu as culturing grounds. All pearl oysters as the sample were imported from Japan. The highest water temperature at Eogu was $23.6^{\circ}C$ in August and the lowest at Kori and Seogwipo were $13.2^{\circ}C$ and $14.0^{\circ}C$c in February, respectively, Phytoplankton was relatively plentiful but mortality of pearl oysters was $20.5\%$, which was twice at Seogwipo, due to high amount of suspended muds. It shows that Seogwipo is better wintering ground even though the amount of phytoplankton is lower than Kori. Average rates of pearl production after 6-months and 15-months period were $58.2\%$ and $48.3\%$ respecitively. Thickness of pearl layer and coating rate were also satisfactory. More than half of the pearls produced was so-called the pink-pearl, the best colour. About $10\%$ of them was the best quality. There were three peaks of D-shape larvae from July to September and it took about one month for D-shape larvae to become seed-shells. Settling was satisfactory and most of them settled at 1$\~$3 m layer and the best was 2 m-layer. Success of settling was supposed due to high water temperature and low precipitation than the normal year.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.53-60
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• 2009

Thirty one Hanwoo steers were used in a completely randomized design experiment to see the effects of concentrate feeding method (group vs. individual feeding) and age at slaughter (26 vs. 28 months of age) on growth performance, feed intake and carcass characteristics. Steers were randomly assigned to one of four groups, G26 (group feeding slaughtered at 26 months of age), G28 (group feeding slaughtered at 28 months of age), I26 (individual feeding slaughtered at 26 months of age) or I28 (individual feeding slaughtered at 28 months of age). Amount of concentrate were restricted to 1.5% of BW for the growing period and 1.8% of BW for the early fattening period in both groups. For the late fattening period, concentrate were given ad libitum for G26 and G28, but were given up to 1.7% of BW for I26 and I28. Average daily gains were higher in individual feeding groups (I26 and I28) than those in group feeding groups (G26 and G28) for the early fattening period (p<0.05). ADGs were higher in group feeding groups than those in individual feeding groups (p<0.05). Concentrate intake in individual feeding groups tended to be higher compared to that in group feeding groups for the early fattening period, but tended to be higher in group feeding groups compared to that in individual feeding groups for the late fattening period. Feeding method or slaughter age had no significant effects on carcass characteristics, yield grade and quality grade. Shear force and tenderness of longissmus muscle were higher in groups slaughtered at 28 months of age than in groups slaughtered at 26 months of age (p<0.05). Feeding method or slaughter age had no effects on cooking loss, water holding capacity, juiciness, flavor, moisture, protein and fat of longissmus muscle.

• Journal of Life Science
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• v.18 no.9
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• pp.1186-1193
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• 2008

The growth performance of pangasiid catfish (Pangasius hypophthalmus), silver carp (Hypophthalmichthys molitrix) and catla (Catla catla) was evaluated in polyculture at varied combinations and stocking ratios in earthen pond for a period of 16 weeks. Combinations of pangasiid catfish, silver carp and catla with the total density of 30,000 fish per hectare were evaluated. A commercial pelleted feed containing 28% crude protein and 6% lipid was fed only to pangasiid catfish at the rate of 8% of body weight during the first six weeks, 6% during the second six weeks and 4% thereafter twice daily. The growth and feed utilization efficiency of pangasiid catfish were found similar in all treatments. The growth of silver carp was markedly decreased upon the increase of its own stocking density. The highest growth of silver carp achieved in polyculture of pangasiid catfish, silver carp and catla at 2:1:1 ratio where density of silver carp was lowest. The growth of catla was found to be affected by the presence of silver carp. The growth rate of catla markedly declined with the increase of silver carp density. The highest growth of catla obtained in polyculture of pangasiid catfish only with catla stocked at 1:1 ratio. The highest yield and economic return achieved in polyculture of pangasiid catfish, silver carp and catla at the ratio of 2:1:1 due to higher growth of silver carp and higher market value of catla. The water quality conditions in all different treatment ponds were within optimum ranges throughout the culture period and the values did not show any significant variation (p>0.05) among the treatments.

• The Korea Journal of Herbology
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• v.37 no.5
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• pp.89-96
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• 2022

Objectives : This research was performed to analyze the components in the different parts of Lythrum salicaria L. and to compare which parts of L. salicaria L. are appropriate for food development. Methods : L. salicaria L. was extracted in 20% EtOH at 100 ℃ for 4 hours. Cytotoxicity was investigated in 3T3-L1 cells after treatment of 10-500 ㎍/ml L. salicaria L. for 24 hours. Total polyphenol content (TPC) was estimated using 1 N Folin-ciocateu reagent. 2,2-Diphenyl-1-picryhydrazyl (DPPH) radical scavenging activity was estimated using DPPH reagent and gallic acid. The chemical composition was analyzed by high-performance liquid chromatography (HPLC). 1) Results : The half maximal inhibitory concentration (IC50) in the extracts of the whole plant, aerial parts, and root parts was 350 ㎍/ml, over 500 ㎍/ml, and 150 ㎍/ml, respectively. The TPC in the extracts of the whole plant, aerial parts, and root parts was 527.1 mg/g, 422.6 mg/g, and 781.1 mg/g, respectively. The averages of vitexin contents in the aerial parts, and root parts were 256.7 ± 154.9 ㎍/g and 266.1 ± 63.2 ㎍/g, respectively. The averages of TPC in the leaves, roots, flower stalks and stems were 224.0 ± 53.7 tannin acid (TA) mg/g, 221.8 ± 70.2 TA mg/g, 249.8 ± 34.4 TA mg/g, and 67.7±8.9 TA mg/g, respectively. The averages of DPPH radical scavenging activity in the leaves, roots, flower stalks, and stems were 282.01 ± 43.3 gallic acid equivalent (GAE) 𝜇mole/g, 260.16 ± 44.1 GAE 𝜇mole/g, 288.0 ± 9.3 GAE 𝜇mole/g, and 97.6 ± 10.7 GAE 𝜇mole/g, respectively. Conclusions : There were no significant differences in the content of components or antioxidant activity in the aerial parts compared to those in the whole plant of L. salicaria L. Furthermore, the root parts had low extract yield, cytotoxicity, and quality control problems, therefore our results suggest that the use of the aerial part of L. salicaria L. would be the most appropriate for food development.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.244-250
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• 2013

The objective of this study was to investigate the effects of marinade condition (injection and tumbling process) on the physicochemical and sensory characteristics of marinade steak. The pH of marinade steaks was in the range of 5.26-5.51, with the highest level in the injection/tumbling (IT) treatment, while injection processes tended to result in higher pH levels (p<0.05). Salinity and sweetness contents were determined to be the highest in the IT treatment. Cooking loss was highest in the control (Immersion, 6 hr), but there were no significant differences between control and injection/tumbling, injection/ vacuum/tumbling (IVT), and vacuum/tumbling treatments. Hardness was in the range of 8.01-13.99 kg, with the lowest level observed for the IVT treatment, and the highest level observed for the control. However, there were no significant differences in hardness between injection process treatments and non-injection process treatments. Therefore, injection and tumbling processes have a similar effect on meat tenderness. In the sensory evaluation, there was a significant difference between the control, injection and tumbling process treatments in terms of tenderness, texture preference and taste. These results suggest that injection and tumbling processes improved tenderness, product yield and sensory preference in meat products.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.41-51
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• 1999

This study was conducted to investigate the effects of local climatic conditions on the annual increment of Korean white pine planted in Gapyung and Yaungdong. For this, stand variables such as mean DBH, mean height, basal area per hectare, and volume per hectare by stand age were measured and summarized for each locality. Based on these statistics, annual increments for 8 years from stand age 10 to 18 were calculated for each of stand variables. A topoclimatological technique which makes use of empirical relationships between the topography and the weather in study sites was applied to produce normal estimates of monthly mean, maximum, minimum temperatures, relative humidity, precipitation, and hours of sunshine. Then, the yearly climatic variables from 1990 to 1997 for each study site were derived from the spatial interpolation procedures based on inverse- distance weighting of the observed deviation from the climatic normals at the nearest 11 standard weather stations. From these estimates, 17 weather variables such as warmth index, coldness index, index of aridity etc., which affect the tree growth, were computed on yearly base for each locality. The deviations of measured annual increments from the expected annual increments for 8 years based on yield table of Korean white pine were then correlated with and regressed on the yearly weather variables to examine effects of local climatic conditions on the growth. Gapyung area provides better conditions for the growth of Korean white pine in the early stage than Youngdong area. This indicates that the conditions such as low temperature, high relative humidity, and large amount of precipitation provide favor environment for the early growth of Korean white pine. A ccording to the correlation and regression an analysis using local climatic conditions and annual increments, the growth pattern of Gapyung area corresponds to this tendency. However, it was found that the relationship between annual increments and local climatic conditions in Youngdong area shows different tendency from Gapyung. These results mean that the yearly growth pattern could not sufficiently be explained by climatic conditions with high variance in yearly weather variables. In addition, the poor growth in Youngdong area might not only be affected by climatic conditions, but also by other environmental factors such as site quality.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.557-565
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• 2011

The objectives of this study were to investigate the physicochemical characteristics of soybean leaves in different cultivars and to develop a soybean curd prepared with soybean leave powder as a functional food. Four cultivars (Daewonkong leaf, Daepungkong leaf, Hwangguemkong leaf, and Seoritae leaf) were selected for this experiment. A significant difference was observed in the proximate composition of soybeans leaves (p<0.05). Soybean leaves had the highest content of carbohydrates. The mineral composition and isoflavone content in soybean leaves were significantly different among the cultivars (p<0.05). In particular, Daepongkong leaf had the highest content of genistein, daidzein, and total isoflavones. This study was also conducted to determine the quality characteristics of a soybean curd developed from daepongkong leaf with various concentrations (0, 0.1, 0.2, and 0.3%) of soybean leaf powder (SLP). The soybean curd yield rate increased according to the level of SLP added, whereas the L and a color values decreased. In the sensory evaluation, intensity scores for color, after taste, leafy taste, and chewiness were highest for the 0.3% soybean curd. The soybean curd with 0.2% SLP soybean milk attained the highest overall acceptability score. These results showed that soybean leaf was preferred over soybean curd containing 0.2% soybean leaf powder.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.6
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• pp.111-121
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• 2019

Evapotranspiration (ET) of vegetation is one of the major components of the hydrologic cycle, and its accurate estimation is important for hydrologic water balance, irrigation management, crop yield simulation, and water resources planning and management. For agricultural crops, ET is often calculated in terms of a short or tall crop reference, such as well-watered, clipped grass (reference crop evapotranspiration, $ET_o$). The Penman-Monteith equation recommended by FAO (FAO 56-PM) has been accepted by researchers and practitioners, as the sole $ET_o$ method. However, its accuracy is contingent on high quality measurements of four meteorological variables, and its use has been limited by incomplete and/or inaccurate input data. Therefore, this study evaluated the applicability of Backpropagation Neural Network (BPNN) model for estimating $ET_o$ from less meteorological data than required by the FAO 56-PM. A total of six meteorological inputs, minimum temperature, average temperature, maximum temperature, relative humidity, wind speed and solar radiation, were divided into a series of input groups (a combination of one, two, three, four, five and six variables) and each combination of different meteorological dataset was evaluated for its level of accuracy in estimating $ET_o$. The overall findings of this study indicated that $ET_o$ could be reasonably estimated using less than all six meteorological data using BPNN. In addition, it was shown that the proper choice of neural network architecture could not only minimize the computational error, but also maximize the relationship between dependent and independent variables. The findings of this study would be of use in instances where data availability and/or accuracy are limited.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.143-150
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• 1998

In order to evaluate the nitrogen (N) balance, from the different application methods and levels of $^{15}N$ applied to a satsuma mandarin orchard soils in spring, we surface-applied N as urea at the rates of 50 (water-dissolved), 100 (solid and water-dissolved) and 150% (solid) of the recommended rate ($180kg\;ha^{-1}$) in spring (lebeled N), summer (nonlebeled N) with application ratio of 5:2:3. Fruit yield and quality were not significantly affected by any treatment. Nitrogen contents of spring flush leaves in late August were 3.0% regardless of the treatments. The N recovery by parts of tree itself was in the order of leaves, fruits, roots, stems, and the highest recovery per tree was 22.3% in the 50% recommended water-dissolved surface broadcast while there were not much differences for N recovery (11.9 to 13.6%) among the other three treatments. Total N content in top 30cm of soils was 0.47% regardless of the treatments, but N proportion and total residual N from the fertilizer applied increased with increasing N rate while the N recovery in soils decreased. For the recommended N rate, N proportion and the residual N from the fertilizer applied were greater in the water-dissolved surface broadcast than those in soils surface broadcast. The highest total (tree + soils) N recovery was 70.9% in the 50% recommended water-dissolved surface broadcast, but tended to decrease to 52.2, 46.6, and 43.2% for the recommended water-dissolved surface broadcast, 100 and 150% of the recommended solid surface broadcast, respectively.