• Korean journal of food and cookery science
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• v.28 no.2
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• pp.207-214
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• 2012

In this study, cabbage ($Brassica$ $oleracea$ var. $capitata$) Kimchi was made packed into four kinds of packaging materials, PET vessel, PP tray, OPP/AL/PE film and Nylon/PE/LLDP film, and the effects of these packaging materials on Kimchi quality characteristics, such as lactic acid bacteria counts, salinity, sugar contents, pH, total acidity, electron donating ability were examine as well as their effects on the sensory qualities after storage at a temperature of $4^{\circ}C$. The pH change ranged from pH 6.24 to 6.43 shortly after manufacture, and did not significantly change until 7 days of storage. However, it began to decrease rapidly after 14 days. On the 35th day of storage, the acidity was 0.79% in the PET vessel and 0.83% in OPP/AL/PE. Therefore, the PET vessel and OPP/AL/PE were considered appropriate packaging materials for Kimchi storage. The salinity did not change significantly during the storage period, and the sugar content generally increased in the four kinds of packaging materials, but decreasing after the 7th day of storage. After 14 days of storage, the Kimchi stored in the OPP/AL/PE film showed the highest lactic acid bacteria counts. Although the electron donating ability was the highest after proper time for fermentation, it decreased in all the packaging materials after the proper time for fermentation. However, the OPP/AL/PE film had an antioxidant potential of up to 93.18%. In the sensory evaluation, fermented Kimchi was found to be superior unfermented Kimchi. In addition, the Kimchi stored in the OPP/AL/PE film for 14 days showed the high score of 6.70 and 6.60 in overall preference. Therefore, the results of this study provide basic knowledge on the fermentation level and packaging material's condition for commercialization of small packed cabbage Kimchi. Henceforth, industrialization must include a variety of studies under these conditions to increase the merchantability.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.174-186
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• 2007

Amphora coffeaeformis and Achnanthes longipes are commonly found as dominant benthic microalgae in Jeju coastal water throughout the year. In order to investigate pharmaceutical uses of these diatoms, each single species was isolated with micropipette under phase contrast microscope and subcultured with synthetic seawater media which was enriched with F/2 media, trace metal solution and $Na_2SiO_3$). Growth characteristics of these species were also determined with different combination of salinity, nutrients concentration and temperature. Thereafter, mass culture of each species was done based on the maximum growth condition. Biomass was collected after two weeks of mass culture and freeze dried for antioxidant study. The antioxidant properties of different fractions (n-hexane, chloroform and ethylacetate) obtained by solvent fractionation of 80% methanolic extract of two microalgae were investigated for free radical, reactive oxygen species scavenging (Super oxide, Hydrogen peroxide, Hydroxyl radical and Nitric oxide), metal chelating and lipid peroxidation inhibition activities. All fractions of A. longipes showed higher $DPPH^{\cdot}$ (free radical) scavenging activities (n-hexane: 89.0%, Chloroform: 76.0%, Ethylacetate: 66.0%, Methanol: 90.6% and aqueous residue: 63.0%). N-hexane fraction of A. longipes showed significantly higher activity (49.0%) on nitric-oxide. Ethylacetate fraction of A. longipes and aqueous residue of A. coffeaeformis exhibited 64.0% and 75.6% metal chelating activity which was higher than commercial antioxidants (${\alpha}$-tocopherol: 18.0% and BHT: 16.0%). The n-hexane fraction of A. coffeaeformis had 67.5% activity on $DPPH^{\cdot}$. Chloroform and n-hexane fractions of A. coffeaeformis exhibited 46.2% and 47.6% $H_2O_2$ scavenging effects which were closely similar to commercial antioxidants (${\alpha}$-tocopherol: 49.2% and BHT: 58.6%). Chloroform and ethylacetate fractions of A. longipes and fraction of n-hexane and chloroform of A. coffeaeformis showed better lipid peroxidation activities than ${\alpha}$-tocopherol. These data suggest that both organic and aqueous fractions have good antioxidative compounds with different antioxidant properties.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.955-960
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• 2012

In most agricultural soils, ammonium ($NH_4{^+}$) from fertilizer is quickly converted to nitrate ($NO_3{^-}$) by the process of nitrification which is crucial to the efficiency of N fertilizers and their impact on the environment. The salinity significantly affects efficiency of N fertilizer in reclaimed tidal soil, and the soil pH may influence the conversion rate of ammonium to nitrate and ultimately affect nitrogen losses from the soil profile. Several results suggest that pH has important effects on recovery of fall-applied N in the spring if field conditions are favorable for leaching and denitrification except that effects of soil pH are not serious under unfavorable conditions for N loss by these mechanisms. Soil pH, therefore, deserves attention as an important factor in the newly reclaimed tidal soils with applying N. However, fate of N studies in a newly reclaimed tidal soils have been rarely studied, especially under the conditions of saline-sodic and high pH. Therefore, understanding the fate of nitrogen species transformed from urea treated into the reclaimed tidal soil is important for nutrient management and environmental quality. In this article, we reviewed yields of rice and fate of nitrogen with respect to the properties of reclaimed tidal soils.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.756-762
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• 2011

This study was conducted to investigate the effects of moisture content on microbiological stability and texture characteristic of dry-cured ham. The moisture content of dry-cured hams was adjusted to 35% (C) or 45% (T) and then vacuumpackaged after slicing to a 1 inch thickness. All packaged dry-cured hams were stored at $10^{\circ}C$ for 3 mon, and physicochemical analyses and a sensory evaluation were conducted to verify the quality of dry-cured hams during four different storage periods. Moisture content was significantly higher in T (44.89%) compared to that in C (35.03%). However, crude fat content was higher in C (14.08%) than that in T (11.11%). The pH, salinity, and shear force were higher in C than those in T, and dry-cured hams derived from C seemed to provide low lipid oxidation stability during storage. In contrast, T showed high CIE $L^*$, CIE $a^*$ and CIE $b^*$, and aw values when compared to dry-cured hams from C. Total plate counts and Lactobacillus tended to increase with the increase in storage period, and both were lower in T than those in C after 1 mon of storage. Our results indicate that 45% moisture content improved dry-cured ham quality as compared to that of dry-cured hams containing 35% moisture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1715-1724
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• 2015

The combined effects of a sanitizer mixture solution and antimicrobial ice on the quality of salted Chinese cabbages were examined. Salted Chinese cabbages were treated with a sanitizer mixture (comprised 50 ppm aqueous $ClO_2$ and 0.5% citric acid), packed in 2% brine and antimicrobial ice, and stored for 12 days at 4 and $10^{\circ}C$. Microbiological data on the salted Chinese cabbages after washing with the sanitizer mixture indicated that the populations of total aerobic bacteria, and yeast and molds decreased by 2.20 and 1.28 log CFU/g after treatment with the sanitizer mixture. In addition, coliforms population of salted Chinese cabbage after 12 days storage at $4^{\circ}C$ in the combined mixture of the sanitizer and antimicrobial ice was 3.22 log CFU/g, which was a significantly different from that of control (5.46 log CFU/g). The combined treatment of sanitizer mixture, antimicrobial ice, and low temperature at $4^{\circ}C$ suppressed reduction of pH and elevation of titratable acidity, resulting in delaying the growth of lactic acid bacteria. Differences in salinity, hardness, and Hunter's $L^*$, $a^*$, and $b^*$ values among treatments were negligible during storage at $4^{\circ}C$. Therefore, this study suggests that a combination of sanitizer mixture, antimicrobial ice treatment, and low temperature storage could improve the microbial safety and quality of salted Chinese cabbages during storage.

• Korean Journal of Ichthyology
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• v.18 no.1
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• pp.36-44
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• 2006

The distribution patterns of anchovy eggs and larvae and environmental characteristics such as oceanographic conditions and meteorological factors in the eastern part of Jeju Strait, Korea from June to October 2003 were investigated. During the sampling periods, the anchovy spawned on the coastal area mainly and approximately 85% of total egg abundance occurred in only two months, from July to August, suggesting that the main spawning season of anchovies is considered in summer from July and August in the study area. Relatively high proportions of the anchovy larvae larger than 20 mm TL observed in the eastern part area. These facts suggest that anchovy larvae gradually moved out to the eastern part of study area. Most wind speeds were markedly reduced to below 10 m/s with the exception of a few days and the precipitation was concentrated (37%) from July to August when the anchovy eggs and larvae occurred abundantly. Results of correlation analysis showed that the anchovy egg abundance correlated with the increasing chlorophyll a and copepod biomass. It is considered that the plankton biomass in the sea area would have significant effects on the anchovy spawning. In addition, salinity variations also had significant effects on the abundance of anchovy larvae, with increasing water temperature.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.318-323
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• 2008

We studied on the effects of slurry composting and biofiltration liquid fertilizer (SCBLF) on growth of two-year-old poplar clones planted in a reclaimed land mounding soil. The soil on the experimental site had lower concentrations of both exchangeable cations and salinity than before reclamation. However, the content of organic matter was low compared with the most soils. We applied SCBLF to the poplars six times and 5 L in each time for 80 days. Ten clones of six poplar species or hybrids were tested in this study: Populus alba ${\times}$ P. glandulosa(Clivus, 72-30, 72-31, Bongwha1), P. deltoides ${\times}$ P. nigra(Dorskamp), P. deltoides(Lux) ${\times}$ P. deltoides(Harvard)(97-19), P. euramericana(Eco28, I-476), P. nigra ${\times}$ P. maximowiczii(62-2) and P. Koreana ${\times}$ P. nigra var. italica(Suwon). Growth performance varied more among clones than among species. Average height growth of treated plots was 18% greater than control, and clones Clivus, 97-19, Eco28 and Dorskamp were more vigorous than other clones. Diameter at breast height in treated plots was 41% greater than control, and 97-19, Dorskamp, Eco28 and Clivus were the four best clones in this respect. Mean leaf area of treated trees was 26% greater for control trees. Chlorophyll content was similar between treated and controlled trees. Total nitrogen values in leaves were much higher in treated trees 18%. SCBLF treatment on poplars planted in reclaimed land helped tree growth.

• The Korean Journal of Zoology
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• v.9 no.1
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• pp.7-15
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• 1966

In a previous paper, the dirunal and monthly changes of the tidal flat temperature and chlorinity were observed. In this paper the resistance of the young short necked clam in various growth stages to the temperature, to the chlorinity and to the exposure were studies. The young clam used were in early (E), medium (M) and late (L) young stages whose shell lengths were 2.0-3.5mm, 9.0-11.0mm. and 14.0-16.0mm., respectively. The results were : 1. At various sea water temperatures , the chlorinity resistance of the young clam was directly proportional to the shell length. 2. When both inadequate sea water temperature and abnormal chlorinity are simultaneously applied, the resistance of these young clams was more markedly reduced than the case of applying either one of these conditions. 3. In clams of M and L, no lethal effect were observed when daily immersion of four to eight hours for a week into the sea water of any concentration of chloriity at 26-34$^{\circ}C$, whereas in E, 37-90% of mortalities were obtained by immersion of eight hours daily into both the fresh water and the sea water of higher chloriniites (more than 23.5$\textperthousand$ Cl) at the same temperature above. 4. The lower critical thermal maximum for lethal to the young clam was 38$^{\circ}C$. With four hours immersion daily at the water temperature of 38$^{\circ}C$, the mortalities of E, M and L to the lower chlorinities (less than 6.7$\textperthousand$Cl) were 100, 70-100 and 27-37% respectively ; to the higher chlorinities (more than 23.5$\textperthousand$Cl) 10-70, 10-37 and 3 % respectively ; to the normal range of chlorinities (13.4-16.8$\textperthousand$Cl) 0-13, 3 and 0 % respectively. 5. No lethal effects were observed in E and M clams immersed continuously for seven days in sea water with chlornities of 7.2 -21.7$\textperthousand$Cl at 18-24$^{\circ}C$, while notable mortalities were observed in E which had been kept at lower (less than 4.8$\textperthousand$ Cl) and higher (more than 24.1$\textperthousand$ Cl) chlorinites. 6. Although the resistance of the young clam to the chlorinity may have to be related closely to the life history of the clam prior subject to the experiment, the adapted chlorinity range was 7.2-19.3$\textperthousand$ Cl and the optimum range was 13.4-16.8$\textperthousand$Cl. 7. Remarkable lethal effects were observed for the E and M clams to the exposure temperature of 38$^{\circ}C$ whereas the L and had no such fatal results.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.405-413
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• 2016

Quinoa (Chenopodium quinoa Willd.) is a plant native to the Andean region that has become increasing popular as a food source due to its high nutritional content. This study determined the optimal photoperiod, light intensity, and electrical conductivity (EC) of the nutrient solution for growth and yield of quinoa in a closed-type plant factory system. The photoperiod effects were first analyzed in a growth chamber using three different light cycles, 8/16, 14/10, and 16/8 hours (day/night). Further studies, performed in a closed-type plant factory system, evaluated nutrient solutions with EC (salinity) levels of 1.0, 2.0 or $3.0dS{\cdot}m^{-1}$. These experiments were assayed with two light intensities (120 and $143{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) under a 12/12 and 14/10 hours (day/night) photoperiod. The plants grown under the 16/8 hours photoperiod did not flower, suggesting that a long-day photoperiod delays flowering and that quinoa is a short-day plant. Under a 12/12 h photoperiod, the best shoot yield (both fresh and dry weights) was observed at an EC of $2.0dS{\cdot}m^{-1}$ and a photosynthetic photon flux density (PPFD) of $120{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. With a 14/10 h photoperiod, the shoot yield (both fresh and dry weights), plant height, leaf area, and light use efficiency were higher when grown with an EC of $2.0dS{\cdot}m^{-1}$ and a PPFD of $143{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Overall, the optimal conditions for producing quinoa as a leafy vegetable, in a closed-type plant factory system, were a 16/8 h (day/night) photoperiod with an EC of $2.0dS{\cdot}m^{-1}$ and a PPFD of $143{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$.

• Ocean and Polar Research
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• v.40 no.4
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• pp.203-212
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• 2018

Zoospore release and germling growth of endophytic Ulvella ramosa were examined under various temperatures (10, 15, 20, $25^{\circ}C$) ${\times}$ irradiances (20, 60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Additional growth experiments were performed at different salinities (15, 25, 35, 45 psu) and daylengths (8, 12, 16 h). Growth of host Gracilaria vermiculophylla (Ohmi) Papenfuss was estimated under combinations of temperatures (15, 20, 25, $30^{\circ}C$) and irradiances (20, 60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Endophyte effects on the host growth were tested in the two temperatures (20, $30^{\circ}C$) and irradiances (60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Zoospore release was maximal at $20^{\circ}C$ and $20{\mu}mol\;photons\;m^{-2}s^{-1}$, and germlings grew best under $20^{\circ}C$ and $60{\mu}mol\;photons\;m^{-2}s^{-1}$. No salinity effect on the growth of endophytes was found but endophyte growth was maximal under the daylength of 12 h. G. vermiculophylla grew better at higher irradiances but no growth differences were found between temperatures of $15-30^{\circ}C$. The growth of host species was significantly inhibited by endophytes under $20^{\circ}C$ and $60{\mu}mol\;photons\;m^{-2}s^{-1}$, but host G. vermiculophylla grew well in the endophyte inactive culture conditions of $30^{\circ}C$ and $100{\mu}mol\;photons\;m^{-2}s^{-1}$. In conclusion, endophyte effects on the production of host G. vermiculophylla could be minimized by controlling cultivation depth and harvest period to inhibit endophyte activity.