• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.930-936
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• 2004

Effects of rice cultivars and degree of milling (DM) on composition, pasting properties, total phenolic contents, and distribution of phenolic acids were investigated. Rice and bran fractions with 94.4, 92.0, and 90.4% milling yields from brown rice of four cultivars (Odae, Nampyung, Chucheong, and Ilmi) were used. Fat and ash contents of milled rices decreased with increasing DM, whereas protein contents were not affected. In rice bran, differences in fat and ash contents by cultivars were higher than those caused by DM. With increasing DM, gelatinization temperature of rice flour decreased, whereas peak viscosity and hold viscosity at $95^{\circ}C$ increased. While cold viscosity, final viscosity, and setback varied among cultivars, DM had little effect. Total polyphenolic contents in brown rice, milled rice, and rice bran were 93.9-88.8, 30.3-71.9, and 310.0-541.6 mg catechin eq/100g, respectively. Major phenolic compounds were identified as ferulic and p-coumaric acids. Total phenolic content of brown rice (65.9-27.9 mg%) decreased with increasing DM, whereas ratio of ferulic acid composition increased. Chucheong and Ilmi varieties showed biggest reduction of phenolic acid contents by milling. In rice bran, ferulic and p-coumaric acids were 157.8-240.2 and 31.8-90.4 mg%, respectively. Contents of sinapinic, benzoic, and m-hydroxybenzoic acids in rice bran were higher than those of brown and milled rices.

• Applied Biological Chemistry
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• v.12
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• pp.57-67
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• 1969

1) Many bacterial strains identified as Bacillus megeterium, Bacillus subtilis and Bacillus licheniformis were aboundantly found in summer jokal kimchi, but the most dominant strains in summer kimchi were Lactobacillus plantarum and Loctobacllus buchneri. 2) Bacillus groups found in kimchi were sensitive in a low concentration of AF-2, but groups of lactic acid bacteria were resistant to a high concentration of AF-2. 3) Allowable concentration of AF-2 in Korean kimchi is less than 10 p.p.m. 4) AF-2 was not suitable for the juicy kimchi as a preservative because the color of juicy kimchi was somewhat changed into orange red when 10 p.p.m. of AF-2 was added. 5) High concentration of AF-2 leads the hetero-fermentation of kimchi bacteria to the homofermentation. 6) Microflora of kimchi was influenced even in the concentration of 10 p.p.m. but it was impossible to check the acidification of kimchi in summer with 50 p.p.m. concentration of AF-2. 7) About 25% of AF-2 was consumed in kimchi fermentation for day at $23^{\circ}-25^{\circ}C$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.273-281
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• 2013

Based on the results of continuous flux measurements at the Gimje paddy flux site in the southwestern coast of Korea, carbon dioxide and energy exchanges between customarily cultivated rice-barley double cropping paddy field and the atmosphere during the 2012 rice growing season (from $9^{th}$ Jun. 2012 through $20^{th}$ Oct. 2012) were analyzed. Carbon dioxide and energy (H, LE) fluxes were estimated by the eddy covariance method. Environmental parameters (net radiation, precipitation, etc.) and plant biomass (LAI, plant height, etc.) were measured along with fluxes. After the quality control and gap-filling, the observed fluxes were analyzed. The results have been showed that net ecosystem exchange (NEE), gross primary production (GPP), and ecosystem respiration (Re) during the rice cropping period were -277.1, 710.3, and 433.2 g C $m^{-2}$, respectively.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.151-155
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• 1983

Photosynthetic activity of two rice varieties "Suweon 318, Nagdongbyeo" and two species of grass weeds, two species of sedge weeds, and four species of broadleaf weeds was measured at 5, 10, 20, 30, 40, 50 Klux light intensity. Relative photosynthetic activity of weed species was high in the decreasing order in Cyperus serotinus, Echinochloa grusgalli var caudata, Bidens tripartita, Monochoria vaginalis, and Ludwigia prostrata, while respiration rate was high in Bidens tripartite, Monochoria vaginalis and Cyperus serotinus. Light saturation point of Monochoria vaginalis and Sagittaria pygrnaea may be considered as at 30 klux and photosynthetic rate of other weed species increased with increasing light intensity. Photosynthetic activity of weed species was generally two times higher than rice at the light intensity of 50 klux and increased more than rice as light intensity increased. Photosynthetic activity per leaf dry weight and specific leaf area was higher in broadleaf weeds than in grass and sedge weed species.

• Food Science and Biotechnology
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• v.16 no.4
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• pp.515-519
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• 2007

Rapid immunochromatographic assay (ICA) kits were developed using flagella-specific monoclonal antibodies (MAbs) and rabbit polyclonal antibodies for screening Listeria spp. in food. The establishment of different formats, MAb 2B1 as capture antibody and MAb 7A3 or rabbit polyclonal antibodies as detector antibody, was compared. The 2 formats of the ICA kit were shown to have specific reactions with Listeria and no cross-reactivity with any of the non-Listeria including Escherichia coli O157:H7 and Salmonella enteritidis. The detection limits of the ICA kit using the combination of gold-labeled MAb 7A3 and MAb 2B1 showed $1{\times}10^5$ and $1{\times}10^6\;CFU/0.1\;mL$ at 22 and $30^{\circ}C$, respectively. The other format of the ICA kit using the combination of gold-labeled rabbit polyclonal antibodies and MAb 2B1 showed $1{\times}10^6\;CFU/0.1\;mL$ at $22^{\circ}C$ but weak signal at 30 culture. The format utilizing MAb was more sensitive than the one using polyclonal antibodies for capture antibody. Samples contaminated with L. monocytogenes 4b culture (9-10, 5-6, and 1-2 CFU/mL) on pork and pasteurized milk were confirmed as positive results. Current data suggests that this ICA kit is a rapid, simple and effective tool to screen for Listeria spp. in food.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.136-143
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• 2011

Early life history of the endangered species Gobiobotia brevibarba was investigated to provide baseline data for biological characteristics and restoration. Adult fish were sampled by spoon net capture at Hongcheon-gun, Gangwon-do, Korea, in April 2010. Eggs were obtained after injection of Ovarprim and were artificially fertilized by the dry method in the laboratory. The mature eggs were slightly adhesive and transparent with greyish and average $1.24{\pm}0.07$ mm in diameter. The hatching of the embryos took place about 120 h after fertilization at a water temperature of $23^{\circ}C$. The newly-hatched larva averaged $5.5{\pm}0.29$ mm in total length. Four days after hatching, they averaged $7.4{\pm}0.26$ mm in total length and their yolk sacs were completely absorbed. From 15 days after hatching, they entered the juvenile stage and reached $9.9{\pm}0.72$ mm in total length. One hundred days after hatching, their band patterns and external form were similar to those of adults, and they averaged $36.0{\pm}3.11$ mm in total length.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.726-732
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• 2014

A traditional Korean seafood (fermented anchovy) is made from the muscle and viscera of anchovies Engraulis japonica. This study was undertaken to investigate the effect of retorting condition on the quality of canned, salt-fermented anchovy fillet using red pepper paste with vinegar. Salt-fermented anchovy fillets were prepared by fermenting anchovies with salt (15%) at $5^{\circ}C$ for 15 days, and then cold air drying the fillets for 1 hour. Each batch of dried fermented anchovy fillets (60 g) was filled with 35 g of mixed red pepper paste with vinegar (red pepper paste 64%, vinegar 2%, starch syrup 13%, sugar 14%, coke 6%, soju 0.4%, crushed garlic 0.3%, ginger 0.3%), placed in a can (RR-90), seamed using a vacuum seamer, and sterilized for either Fo 9 or 11 min in a steam system retort at $121^{\circ}C$. After sterilization, we measured the pH, total volatile basic nitrogen (TVB-N), amino-N, color value (L, a, b), texture profile, thiobarbituric acid (TBA) value, sensory evaluation, and viable bacterial count of the canned fillets. We did not detect viable bacterial counts in cans subjected to either sterilization treatment, and there was no difference in physicochemical and sensory quality between the two. In fact, most sensory evaluators reported difficulty distinguishing the products. Thus, our results show that sterilization for Fo 9 min is preferable to that for Fo 11 min in the preparation of canned salt-fermented anchovy fillet using red pepper paste with vinegar.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.15-27
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• 2011

This study was performed to observe ultrastructure of the gill and to ascertain the effect of salinity on histopathological and ultrastructural changes in the gill of the Japanese clam, Corbicula japonica. Experimental period was 7 days. Experimental groups consisted of control, 5, 10, 20 psu. $LC_{50}$ (96 h.) by the probit was 19.55 psu. Mortality was significantly different from the control (p < 0.05). Inner demibranch of the gill of C. japonica was wider 1.37 times than outer demibranch (p < 0.001). The filament zone on the plica can be distinguished by the six epithelial celll cell; frontal ciliated epithelium ($7{\mu}m$), latero-frontal ciliated epithelium ($5{\mu}m$), postlatero-frontal epithelim ($3{\times}8{\mu}m$), and lateral ciliated epithelium ($5{\mu}m$) in the frontal zone, endothelial cellin the intermediate zone, and abfrontal cell in the abfrontal zone. It had one type of secretory cell that was filled with fibrous substances of low electron density. The gill of C. japonica exposed to 5 psu for 7 days was observed partially disappearance of the cilia, and glycogen granule in the filament. In the 10 psu, gill appeared partially modification of epithelial cell and destruction of the glycocalyx. Gill exposed to 20 psu was extended nuclus of the ciliated epithelial cell, destruction of the organelles, and observed glycogen granules infiltration and numerous vacuoles. Moreover, more than 50% filaments were observed that come out chitinous rod from disappearance of epithelial cell in the filament. Therefore, the destruction of the cilia and epithelial cell induce physiological activity and it may be leading directly to death.

• Food Science and Preservation
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• v.19 no.5
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• pp.744-750
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• 2012

In this study, the optimal conditions for phenolic-compound extraction from medicinal plants were found to be 24 h and about 50% ethanol. The electron-donating scavenging activities (DPPH), ABTS radical-cation decolorization (ABTS), antioxidant protection factor (PF), and thiobarbituric acid reaction substance (TBAR) were measured to determine the antioxidant activities of the extracts of Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L. The total phenolic contents of the extracts of medical plants were determined to be 0.45-3.00 mg/g in the water extracts and 0.33-3.15 mg/g in the 50% ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 85% at the $50{\mu}g/ml$ concentration. The ABTS radical-cation decolorization was above 80% at the $100{\mu}g/ml$ concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) of the Melia azedarach L. extracts was found to be $1.65{\pm}0.40$ PF in the water extracts at the $100{\mu}g/ml$ concentration, and was higher than those of the other medicinal-plant extracts. The TBAR inhibition rates of all the medicinal-plant extracts, except Asparagus cochinchinensis Merr., were above 85% at the $100{\mu}g/ml$ concentration. These results confirmed that the various oriental medicinal plants (Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L.) that were included in this study are useful functional-food sources.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.174-180
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• 2011

This study was conducted to investigate the optimum condition of extraction from fronds of Osmunda japonica to increase antioxidant compounds and antioxidant activity. Powder (1 g) of lyophilized fronds were mixed with three different solvents (MeOH, 80% EtOH and water). Extraction was carried out using not only by immersion (room temp.), heating ($60^{\circ}C$) and stirring (200 rpm) for 6 h, but also by sonication in 42 kHz ultrasonic bath for 15, 30 and 45 min. Extracts were filtered, and adjusted up to 50 mL to determine contents of soluble solids, total polyphenols and total flavonoids. Antioxidant capacity was measured by radical scavenging activity of 0.15 mM DPPH (2,2-diphenyl-1-picrylhydrazyl) and 7.4 mM ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical. Among the solvents, MeOH and 80% EtOH appeared to be effective for extraction. Extract obtained from sonication in MeOH for 15 min resulted high polyphenol contents (45.15 $mg{\cdot}g^{-1}$ db) and DPPH radical scavenging activity ($RC_{50}$= 0.35 $mg{\cdot}mL^{-1}$). The highest flavonoid contents was obtained from immersion or heating extraction with MeOH (38.10~38.10 $mg{\cdot}g^{-1}$ db). ABTS radical scavenging was high in same extraction with 80% EtOH ($RC_{50}$= 0.21~0.22 $mg{\cdot}mL^{-1}$). Altogether, our results indicate that the extraction using ultrasonic bath with MeOH as a solvent (for 15~30 minutes) was the most effective way not only for increasing various antioxidant activities but also for saving labor and time in case of fronds of Osmunda japonica.