• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.53-59
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• 2008

Salt is a major component in salt-fermented shrimp with 25% content. There are various types of salts that have different compositions, which may affect the quality of salt-fermented shrimp. We have investigated effects of various salts such as Korean solar salt (KSS), purified salt (PS), sea-concentrated salt (SCS), glasswort (Salicornia herbacea L.) spray solar salt (GSS), glasswort-sea-concentrated salt (GSCS) and spray-dried salt (SDS) on the physicochemical and sensory properties of fermented shrimps. Ammonia nitrogen content of the salted shrimp prepared with SDS was lower than others until 60 day fermentation. At 90 day fermentation, amino nitrogen contents of salted shrimps prepared with GSCS and GSS (980 mg%) were higher than those of the others while sample prepared with SDS showed the lowest amino nitrogen content (680 mg%). Volatile basic nitrogen content of salted shrimp prepared with SDS was also lower than those of the others between 14 and 60 day fermentation and there were differences among samples in the contents of trimethylamine at 180 day fermentation. Sensory evaluation results indicated significant differences in salty, overall taste and overall acceptance among samples. Overall acceptance was significantly higher in salt-fermented shrimp prepared with KSS, SCS, GSS, GSCS and SDS than in fermented shrimp with PS.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.138-144
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• 2006

Algal growth potential test (AGPT) has been used as a tool for assessing biological productivity potential in the aquatic ecosystems. This study was conducted to compare the productivity potentials of large reservoirs (Lakes Andong, Hapchon and Jinyang, and Naktong estuarine dam) and river sites (Sangju, Koryung, and Samlangjin) located in the Naktong River watershed. AGPT was conducted in both non-monsoon and mosoon season (February, April, July and September) of 2003, using Microcystis aeruginosa as a test alga. The AGPs in the reservoirs were relatively much lower than those of river sites. The river AGPs increased towards upstream close to the influent streams, while it generally decreased towards downstream. Immediately after the abrupt increase in influent discharge in summer, the AGP became similar between midstream and downstream sites. The water quality of river and reservoirs deteriorated during the drought period in accordance with AGP: it was the highest during this period. The AGPs showed the closest correlation with the P concentration, leading to the conclusion that bioavailable P is highly influential to the algal growth in both lentic and lotic ecosystems in the Naktong River watershed. Based on the AGPs, the water quality of tested sites was likely eutrophic. Our results suggest that AGPT be a useful tool in evaluating the productivity potential and trophic state of the water body as well as determining the nutrients that limit the growth of algae.

• Korean Journal of Ecology and Environment
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• v.33 no.2 s.90
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• pp.109-118
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• 2000

The dynamics of inorganic nutrients and phytoplankton population were examined at eight stations of Shihwa Reservoir, which situated near the cities newly constructed and the industrial complex of West-sea in Korea, from January to December 1999. Among environmental factors, average concentration of $NH_4$, SRP and SRSi were $522.7\;{\mu}g\;N/l$, $9.8\;{\mu}g\;N/l$ and $0.26\;{\mu}g\;Si/l$, respectively. Water quality was extremely deteriorated by a great amount of pollutants load into inner reservoir after the event of rainfall. Nutrients concentration was suddenly decreased toward the lower part. While $NO_3$ concentration did not much varied among stations, but it was relatively high in winter season. Chlorophyll-a concentration was high at the upper part of the reservoir, with average of $37.2\;{\mu}/l$, and closely related to the fluctuation of $NH_4$, SRP and SRSi concentrations. The phytoplankton development in the water column was dominated by diatom (autumn), prasinoid (winter) and dinoflagellate (summer). Dominant phytoplankton were composed to Skeletonema costatum of diatom, Prorocentrum minimum of dinoflagellate, Chroomonas spp. of cryptomonad, Eutreptiella gymnastica of euglenoid and Pyramimonas spp. of prasinoid. The large bloom of phytoplankton at the upper zone of the Shihwa Reservoir after inflow of a seawater were consistently observed. In consequence, water quality management of the inlet stream was assessed to be very important and urgent.

• 한국해양학회지
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• v.27 no.3
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• pp.250-258
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• 1992

The oxygen isotope composition of surface waters in the Bransfield Strait was determined as one extra state variable in order to characterize water masses in the region, since salinity is significantly modified due to the freezing and ice-melting in the polar region. The salinity, temperature, and $\delta$/SUP 18/O values vary from 34.0 to 34.5$\textperthousand$, -.05 to 2.1$^{\circ}C$ and -0.50 t -0.26$\textperthousand$, respectively. The combined effects of evaporation, precipitation, freezing, ice-melting are reflected in the widely scattered data. Although it is small, the distribution of $\delta$/SUP 18/O of the Bransfield Strait is strongly affected by the freezing-ice melting rather than the evaporation-precipitation. The ice melted fresh water which has higher temperature, depleted salinity and nutrients may be injected to the Bransfield Strait from the north. The concentrations of nutrients are decreasing gradually from the north to the south. The waters were characterized by two groups of higher (about 19.4) and lower N/P ratio (about 16.7). The lower N/P ratio is found in the northern part where ice-melted fresh water is injected. and the higher N/P ratio is found in the southern part of the Bransfield Strait. Although more precise work is needed, the deference of N/P ratio can be an evidence of the ice melted water injection to the Bransfield Strait. Chlorophyll a concentrations, in general, increase from northwest (Waddell Sea) to the southeast (Smith and Hosseason Islands). Probably the injection of nutrient depleted fresh water from the ice melting reduce the chlorophyll a concentration.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.306-317
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• 2014

This study has been executed to understand the additional and removal processes of nutrients in the Saemangeum Salt-water Lake, and discussed with other monthly-collected environmental parameters such as water temperature, salinity, dissolved oxygen, suspended solids, and Chl-a from 2008 to 2010. $NO_3$-N, TP, $PO_4$-P, and DISi showed the removal processes along with the salinity gradients at the surface water of the lake, whereas $NO_2$-N, $NH_4$-N, and Chl-a showed addition trend. In the bottom water all water quality parameters except $NO_3$-N appeared addition processes indicating evidence of continuous nutrients suppliance into the bottom layer. The mixing modelling approach revealed that the biogeochemical processes in the lake consume $NO_3$-N and consequently added $NH_4$-N and $PO_4$-P to the bottom water during the summer seasons. The $NH_4$-N and $PO_4$-P appeared strong increase at the bottom water of the river-side of the lake and strong concentration gradient difference of dissolved oxygen also appeared in the same time. DISi exhibited continuous seasonal supply from spring to summer. Internal addition of $NH_4$-N and $PO_4$-P in the river-side of the lake were much higher than the dike-side, while the increase of DISi showed similar level both the dike and river sides. The temporal distribution of benthic flux for DISi indicates that addition of nutrients in the bottom water was strongly affected by other sources, for example, submarine ground-water discharge (SGD) through bottom sediment.

• The Korean Journal of Food And Nutrition
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• v.13 no.3
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• pp.201-212
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• 2000

김치에 첨가되는 소금, 고추, 젓갈 등 재료의 종류와 첨가량, 숙성 기간을 달리한 김치를 제조하여 이화학적 성질과 관능검사를 실시하였다. 김치의 PH는 제조당일에는 건고추군의 김치가 다른군 김치보다 높게 나타났고, 생갈은 고추군과 건고추군의 새우젓군 김치가 높게 나타났다. 숙성 3일은 모든 김치의PH가 금격히 감소하였고, 숙성 기간이 길어지면서 점차 감소하였다. 김치의염도는 양념 조건에 관계 없이 숙성9일까지 약감 감소하는 정도였고, 숙성은 염도의 변화에 양향을 주지 않았다. 김치의 적정산도는 양념 조건에 따라 약간의 차이를 보여 제조 당일은 혼합고추군, 멸치액젓군 김치가 다른 김치보다 현저하게 높았고, 숙설 적기인 5일에는 고추의 종류에 관계 없이 새우적순 김치가 더 높은 값을 나타냈다. 김치의 아스코르브산의 변화는 모든 김치에서 숙성초기와 숙성적기 이후에 급격한 감소를 보였다. 관능검사 결과를 종합적으로 비교해보면 외관과 색은 건갈은 고추군 김치가 낮게 나타났고, 신맛은 고추의 종류에 상관없이 젓갈군에서 강하게 평가되었으며 탄산미 또한 젓갈군이 높게 평가받았고 특히 멸치 젓군이 새우젓군보다 약간 높았다. 짠맛은 혼합젓갈군이 가장 강했다. 조직감은 생갈은 고추군과 멸치액적군 김치가 가장 좋았고 건갈은 고추군 김치가 낮게 나타났고 생갈은고추군의 대조군 김치와 혼합고추군의 새우젓군 김치가 강하게 나타났다. 종합적인 맛은 생갈은 고추군, 혼합고추군, 건갈은 고추군 순서이었으며 젓갈군 김치가 대조군 김치보다 월등히 높게 나타났으나 젓갈의 종류에는 크게 영향 받지 않았다.

• The Korean Journal of Food And Nutrition
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• v.28 no.3
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• pp.335-342
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• 2015

We conducted a study on mukeun (long-term fermented) kimchi ripened over one year in an attempt to develop an alternative salt and improve the quality of low-salt kimchi. However, few studies have focused on mukeun kimchi that has been fermented for a short time in different salinity conditions. Therefore, the aim of this study was to investigate the physicochemical characteristics that occur during the fermentation of mukeun kimchi samples produced with different conditions of salinity and fermentation temperature. Kimchi samples were produced at 3 different salinity levels: 1.6%, 2.4%, and 3.2%. Previous studies revealed that the optimum fermentation time at pH 4.1 was 128 hours at $18^{\circ}C$ and 417 hours at $12^{\circ}C$; furthermore, the samples were stored for 12 weeks under the condition of $-1^{\circ}C$ after fermentation. Total cell increased on week 0 of storage and decreased according to the storage period. Total cell was the highest at 3.2% salinity and had a high value at $18^{\circ}C$ temperature during the storage period. Based on the physiochemical results, mukeun kimchi at a salinity of 3.2% can be fermented for a short time, and low-salt kimchi at a salinity of 1.6% and fermented at $18^{\circ}C$, is similar to mukeun kimchi at 2.4% salinity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.203-209
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• 2008

Recrystallization characteristics of salt after removing bittern and impurities from solar salt (SD) were investigated. To remove the bittern, the SD was treated at 30, 40 and $50^{\circ}C$ under 95% humidity. 86% of the bittern was removed when the SD was kept at $30^{\circ}C$ for three weeks. Total amount of impurity in SD was 6.94% (w/w) with organic impurity (5.58%) and inorganic impurity (1.36%). Most organic impurities (89%) were soluble. When the SD was roasted at $350^{\circ}C$ for 40 minutes, 90.14% of the soluble organic impurities were removed; however, the removable organic impurity was reduced, when the SD roasted for 50 minutes at $350^{\circ}C$. L* value decreased while a* and b* values increased when the SD was roasted until 40 minutes at $350^{\circ}C$. In contrast, L* value increased while a*, b* values decreased with SD roasted over 50 minutes at $350^{\circ}C$. The size of recrystallized pure salt was positively correlated to temperature and depth of salt solution, while the crystallization time was negatively correlated to temperature and salinity. Yield of recrystallized salt was negatively correlated to temperature. Overall acceptability tended to increase at low crystallization temperature and high salinity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1577-1583
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• 2012

This study was carried out to examine changes in the quality characteristics of unripe peach Jangachi made from different cultivars during storage at room temperature for 60 days. Based on the results, unripe peach Jangachi-showed decreases in pH of pulps and soaking solutions of all varieties during storage. Salinity of Jangachi tended to increase during storage, whereas it decreased in soaking solutions. Soluble solid contents decreased during storage in all varieties, both in pulps and soaking solutions. Among Hunter's color values, L values decreased, a values increased, and b values decreased during storage in all varieties. Hardness decreased for 30 days of storage and increased slightly thereafter. During storage, yeast and mold counts increased and decreased within the range from 2.30~5.55 log CFU/g, respectively. In the sensory evaluation, Madoka and Nagasawa Hakuho were evaluated as good in overall acceptability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.95-103
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• 2019

Periodontal inflammation, a major kind of periodontal diseases, is characterized to bleed, pain, and teeth loss, and it is resulted from oxidative stress. Membrane-free stem cell extract could avoid the immunogencity rejection by removal of cell membrane. In the present study, we investigated the protective effect of membrane-free stem cell extract from oxidative stress-induced periodontal inflammation in human periodontal ligament fibroblasts (HPLF). In the cell viability measurement, membrane-free stem cell extract showed significant increase of cell viability, compared with the $H_2O_2$-treated control group. To further investigation of molecular mechanisms, we measured inflammation and apoptosis related protein expressions. Membrane-free stem cell extract attenuated inflammation-related protein expressions such as nuclear factor kappa light chain enhancer of activated B cells, inducible nitric oxide synthase, and interleukin-6. In addition, the treatment of membrane-free stem cell extract decreased apoptotic protein expressions such as cleaved caspase-9, -3, poly (ADP-ribose) polymerase, and B-cell lymphoma 2 (Bcl-2)-associated X protein/Bcl-2 ratio in the $H_2O_2$-treated HPLF cells. In conclusion, membrane-free stem cell extract exhibited anti-oxidative stress effects by regulation of inflammation and apoptosis in HPLF, suggesting that it could be used as the treatment agents for periodontal inflammatory disease.