• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.52-60
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• 2016

The biological activity of polysaccharide is greatly influenced by polysaccharide structure and molecular distribution. Here, we developed a rapid and convenient isolation method for fractionating polysaccharides with different characteristics and optimized it using a polysaccharide mixture from Korean persimmon leaves. A crude polysaccharide mixture, persimmon leaves-enzyme (PLE) fraction, was isolated from persimmon leaves digested with pectinase and ethanol precipitation. The PLE fraction was further fractionated with a serially diluted ethanol solution (ethanol : deionized water=4:1, 2:1, 1.5:1, 1:1, and 0.5:1) to produce 10 subfractions (five precipitate fractions labeled from PLE-4 to PLE-0.5 and five supernatant fractions labeled from PLE-4S to PLE-0.5S). HPLC analysis indicated that PLE-4 and -2 consisted of diverse polysaccharides, whereas PLE-1.5, -1, and -0.5 contained high molecular weight (MW) polysaccharides. The fractions from PLE-4 to PLE-1 were mostly composed of 13 different characteristic sugars in rhamnogalacturonan (RG) I and II, and the sugars contained an arabino-${\beta}$-3,6-galactan moiety. However, PLE-0.5 did not contain RG-II or ${\beta}$-arabino-3,6-galactan. Treatment of macrophages with fractions PLE-1.5S and PLE-1S led to a $10{\mu}g/mL$ increase in interleukin (IL)-6 production, whereas treatment with PLE-4S and PLE-2S fractions composed of low MW polysaccharides resulted in reduced levels of IL-6. These results indicate that this isolation method may be useful for the rapid and convenient fractionation of bioactive RGs from polysaccharide mixtures with various properties.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.47-53
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• 2012

Increasing concerns over green farming technology, plant growth promoting rhizobacterium (PGRP) having growth promoting as well as plant disease suppressing properties was recently preferred to use for biological control of plant pathogens infecting plant. We measured the influence of the selected microbial consortium agents-a mixture of PGPR strains-, commercial bio-fungicide, and chemical pesticides on soil microbial community in red pepper field. The activities of soil enzyme such as dehydrogenase, urease, phosphatase, ${\beta}$-glucosidase, and cellulase were analyzed to investigate that of soil microbial community. We also measured plant length, main stem, stem diameter, number of branches and yields of red-pepper in order to observe the red pepper growth promotion. The results of measuring enzyme activities were dehydrogenase 3.5584 ${\mu}g$ TPF $g^{-1}h^{-1}$, urease 15.8689 ${\mu}g$ $NH_4{^-}N$ $g^{-1}h^{-1}$, phosphatase 0.5692 ${\mu}g$ PNP $g^{-1}h^{-1}$, ${\beta}$-glucosidase 2.4785 ${\mu}g$ PNP $g^{-1}h^{-1}$, and cellulase 86.1597 ${\mu}g$ glucose $g^{-1}h^{-1}$ in the soil treated with the microbial consortium agents, so it came out to be very active in the soil. Observing the growth of red-peppers, the main-stem length and the stem diameter were 6.1% and 8.1% higher in the soil treated with the selected microbial consortium agent than the chemical pesticides. After harvesting, yields were 7.3% higher in the soil treated with selected microbial consortium agents than the chemical pesticides. These results showed that microbial consortium agents contribute to increasing soil microbial diversity, growth promoting, and yield of red pepper.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2000.11a
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• pp.59-75
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• 2000

This study was carried out to develop a DNA marker for identifying between Korean cattle (Hanwoo) and other breeds. First experiment was performed to isolate Hanwoo specific DNA marker at sequence characterized amplified regions (SCARs). Five breeds of cattle including Hanwoo, Holstein, Hereford, Angus and Charolais were represented with the from 8 to 20 individuals. Fourteen primers of 300 arbitrary primers of 10 nucleotides showed reproducible polymorphism across the breeds. An amplified band of 0.9 kb in the primer MG-3 showed the specificity to Holstein breed. And MG-6 and MG-12 detected the Hereford and Hanwoo specific markers at the size of 2.0 kb and 1.0 kb, respectively. A 1.0 kb band of MG-12 was cloned and sequenced. A SCAR primer was designed based on the obtained sequences. It was possible to identify the Hanwoo from Holstein breed. Second experiment was carried out to observe the genotype frequencies of MC1R in 1,044 samples of imported beef and eight different cattle breeds including Hanwoo, Holstein, Angus, Brown-Swiss, Charolais, Limousin, Simmental and Hereford. The primers for the amplification of bovine MC1R gene were designed based on a bovine MC1R gene sequence (GenBank accession no.Y19103). A size of 350 bp was amplified by polymerase chain reaction(PCR), digested with two different restriction enzyme, BsrFI and MspA II, and electrophoresed in 2.5% Metaphore agarose gel for determination of genotypes. Genotype frequencies of Hanwoo were 0.10 in E+e and 0.90 in ee. Allele ED was shown in all of Holstein and Angus breeds tested which have black coat color phenotypes. We suggested that SCAR marker and the bovine MC1R gene could be used as a DNA marker for distinguishing beef between Hanwoo and Holstein.

• Membrane Journal
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• v.6 no.3
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• pp.157-165
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• 1996

Polysulfone(PS) membranes were prepared from homogeneous PS solutions by the phase inversion technique. When propionic acid(PA) was added into a casting solution of n-methylpyrrolidone(NMP) and PS, precipitation rate of the solution film was accelerated. This kind of acceleration was consistent, even though a precipitating nonsolvent was changed from water to isopropanol. These phenomena were caused by decrease of nonsolvent tolerance in the casting solution due to addition of PA. PS powder was prepared by precipitation of a 3wt% solution in dimethylformamide(DMF) using ethanol as nonsolvent. Gas adsorption analysis of the powder showed that the capillary condensation sites were found in the powder structure. Membranes prepared from PS solution(15wt%) in NMP had the following characteristics of gas adsorption and water permeation. In gas adsorption analysis, the membrane precipitated using isopropanol showed low uptake of nitrogen gas and the capillary condensation sites were not found. On the contrary, a significant amount of the capillary condensation sites was found in the membrane coagulated by water, which was related to increase of nitrogen uptake. tn the membrane prepared froin the solution including PA, an increase of the Henry's law sites and the Langmuir sites was not found clearly. However, the capillary condensation sites were significantly increased, and the water transport also increased.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1135-1141
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• 1996

In order to investigate the composition and the actual status of extractive nitrogenous compounds in saeujeot, a salted and fermented seawater shrimp(Acetes japonicus), the extract was analyzed separately into extractive nitrogen, free amino acids, oligpopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish markets from July in 1994 November in 1995. The extractive nitrogen of saeujeot was ranging from 430 mg to 528 mg, and the total of free amino acids in it was ranging from 1,509 mg to 2,131 mg, The extract was rich in free amino acids especially in lysine, glutamic acid, leucine, arginine, glycine, histidine, and glutamine, However, the content of most free amino acids was fluctuated from collection to collection. The total of nucleotides and related compounds in the extract was ranging from $1.38\;{\mu}mol\;to\;7.41\;{\mu}mol$, and the rage of fluctuation was essential identical with those of the extractive nitrogen and free amino acids. Homarine, trigonelline, ${\beta}-alaninebetaine$, and glycinebetaine were found in the saeujeot extract. Among them, homarine was the most abundant, ranging from 97 mg to 224 mg, but trigonelline, ${\beta}-alaninebetaine$, and glycinebetaine were very low. TMAO and TMA in the saeujeot extract were $13{\sim}80\;mg\;and\;12{\sim}280\;mg$, respectively. A small amount of creatine (less than 6 mg) and creatinine (less than 1 mg) was detected in all samples.

• Journal of Korean Home Economics Education Association
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• v.24 no.2
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• pp.29-49
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• 2012

The purpose of this study is to look at families as presented on the technology-home economics subject of middle school. To do this, I analyzed the 2007 revised curriculum of the technology-home economics subject, 'Changing Families,' in 11 technology-home economics textbooks (8th grade). The findings are as follows. First, family-related chapters are expanded compared with the previous curriculum in the 2007 revised curriculum. In addition, the new version emphasizes understanding and acceptance of change in families to improve the family life of adolescents. Second, in the 11 types of technology-home economics textbooks, the focusing was on the meaning of the family, the family structure, the function of the family, family roles and family values. There were also no major differences in the aspect of development. Third, in the technology-home economics textbooks, the family was defined as the 'basic group of society', 'a group composed by blood relationships, marriage and adoption', 'an affective group' and 'cohabiting group'. At the same time, there were many cases in which the description of the family was overly romanticized. Such a description of the family does not match the individual family experience of an adolescent. Fourth, all of textbooks dealt with the diversity of the family structure, such as single-parent families, remarriages families, and multi-cultural families. However, the structural characteristics and problems with these types of families are excessively emphasized, which can result in students having stereotypical images of specific family types. Fifth, the explanation of the function of the family was similar among textbooks. The importance of intergenerational cooperation and gender equality was also emphasized. However, such a concept is not considered as proper in a modern society. Thus, the description of a family based on the nuclear family should be sublated. In addition, the explanation of families overall should be developed in such a way that adolescents can interpret their own family experience rather than as an enlightening declaration of the family which disregards the dynamic relationships individual families actually experience.

• Korean Journal of Ecology and Environment
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• v.52 no.2
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• pp.126-135
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• 2019

We carried out a literature review of fish food sources research in the coast - estuary areas of Korean peninsula for the last fifty years(1969~2018). A total of 101 research papers were reviewed, of which 81 were published in domestic journals, 7 were puliched in domestic reports and 14 were published in international journals. When divided into the decade periods, 21 papers (19.4%) between 1990 and 1999 and 26 papers (24.1%) between 2000 and 2009, and 42 papers (48.1%) were published in 2010 and 2018, respectively. When divided into the survey area by a bearing (East sea, South-East sea, South Sea, and West Sea), 65 papers(69.1%) were carried out in the South Sea. Followed by 13 papers (13.8%) in the East Sea and 8 papers (8.5%) in the West Sea and the South-East Sea, respectively. The surveyed area was dominant in Gwangyang Bay (18 papers; 24.3%), followed by Gadeok-do (8 papers; 10.8%). Of the diversity indices, 14 indices were used to calculate the ecological status. The dominant indices were IRI(Index of relative importance), Pi(Prey-specific abundance) followed by E (electivity index) and Bi (dietary breadth index). A total of 11 statistical methods were used to find feeding strategy. The correlation analysis and Bray-Curtis similarity matrix were applied most frequently. In terms of ecological research topics, the papers focused on seasonal or spatial differences before 2000. Since 2000, specifically, the international journal papers have been published based on competition, sympatric, niche overlap and other ecological topics.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.365-373
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• 2020

Biomonitoring Survey and Assessment Manual for lake ecosystem suggest zooplankton collection methods to compare relatively the number of species, population density, and community indices, taking into account the convenience of the field sampling according to the sites' water depth. In this study, the oblique towing and 20 m vertical towing methods presented in the manual were respectively compared with the whole water column-vertical towing and we analyzed the differences and characteristics of zooplankton community information gathered by each collection method. For community indices, there was no difference in the comparison of oblique/vertical towing methods in the shallow lake, but in the deep lake, the diversity and richness indices increased when vertically towing through whole water column rather than when limiting the towing depth to 20 m. In addition, the total zooplankton density collected by the oblique/20 m vertical towing methods was about three times higher than the whole water column-vertical towing method, which means that the density of zooplankton community can be overestimated depending on the collection methods. It appears to be results of differences in the zooplankton density by water layer arising from their vertical distribution and in filtered raw water quantity according to the towing depth/distance. Hence, for zooplankton community information to be used as a functional quantitative indicator representing the entire lake, it would be more appropriate to apply the whole water column-vertical towing method with considering the distribution of zooplankton density by depth and contribution rate of each water layer when converting total zooplankton density.

• Journal of Wetlands Research
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• v.26 no.1
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• pp.62-71
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• 2024

To assess the ecological changes of Korean fir (Abies koreana E. H. Wilson) under climate change conditions, growth and physiological responses were analyzed over a 5-year period in a control group (outdoors) and in a treatment group where the temperature and CO2 levels were elevated to closely resemble RCP 4.5 conditions. The results showed an increasing trend in annual branch length of A.koreana in the climate change treatment group over time. While climate change conditions did not significantly impact the morphological differences of A.koreana leaves, they did influence the biomass of the leaves, suggesting that as climate change progresses, the productivity of A.koreana leaves may decline. On the other hand, the chlorophyll content in A.koreana under climate change conditions was higher in the climate change treatment group, whereas the photosynthesis rate, transpiration rate, water use efficiency and stomatal conductance was higher in the control group. This suggests that an environment with elevated temperature and CO2 could influence an increase in stomatal density, but having a negative impact on photosynthetic reactions. Further research on stomatal density under each environmental treatment will be required to confirm this hypothesis. Additionally, as this study only observed changes in leaf biomass, further empirical research should be considered to understand the changes in biomass of A.koreana under climate change conditions. In conclusion, the environmental adaptability of A.koreana is expected to weaken in the long term under elevated temperatures and CO2.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.280-290
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• 1984

An extensive study has been made on the relationship between the freshness and the compositions of the muscle protein of prawn, Pandalus japonica during the storage under partially frozen condition. The variations of the subunit distribution for sarcoplasmic protein and myofibrillar protein extracted from the samples by changes of freshness were discussed by sodium dodecylsulfate-poly-acrylamide gel (SDS-PAG) electrophoresis. On the other hand, the denaturation constant ($K_D$) of the myofibrillar protein extracted from the prawn stored at $-3^{\circ}C\;and\;-20^{\circ}C$ were successively compared. The prawn muscle contained about $18\%$ of protein with the composition of $32\%$ in sarcoplasmic protein, $56\%$ in myofibrillar protein, $10\%$ in residual intracellular protein and $2\%$ in stroma. The indices for estimating freshness of the muscle were approached to the early stage of putrefaction on the 26th day of the storage with $25.29mg\%$ of total volatile basic nitrogen, $31.36\%$ of K-value and 8.83 of pH. The content of the myofibrillar protein was remarkably decreased with the time during the storage while that of residual intracellular protein was increased. The $K_D$ values of the myofibrillar protein were $9.03{\times}10^{-6}sec^{-1}\;at\;-3^{\circ}C\;and\;4.42{\times}10^{-6}sec^{-1}\;at\;-20^{\circ}C$. The results of the analysis of SDS-PAG electrophoretograms indicated that the sarcoplasmic protein and the myofibrillar protein were composed of 12 subunits and 17 subunits in the muscle of instantaneously killed prawn ana were changed into 8 subunits and 22 subunits in the muscle stored for 26 days, respectively. It is noticeable that 30,000, 41,000, 107,000, 136,000, 170,000 173,000, 185,000, and 198,000 daltons of the newly appeared 8 subunits were found in the myofibrillar protein from the prawn muscle stored for 26 days. The amino acid composition of the muscle protein showed that the most of amino acids were slightly decreased with the days of the storage. With respect to the free amino acid composition of the muscle of instantaneously killed prawn, glycine, proline, arginine, alanine and taurine comprised $93\%$ of the total free amino acids. Taurine, valine, leucine, phenylalanine, serine, lysine, methionine, isoleucine and histidine were increased during the storage period but exceptionally proline was decreased.