• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.285-289
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• 2004

Oceanographic observation and qualitative analysis for deep ocean water in the East Sea were carried out from January 2003 to January 2004, in order to understand the characteristics of deep sea water in the East Sea. Temporal and spatial variation of water masses were discussed from survey of the study area including the coastal sea of Kwangwon province in where the polar front mixing cold and warm water masses were formed. On the basis of the vertical profiles of temperature, salinity and dissolved oxygen, water masses in the study area were divided into 5 major groups; (1) Low Saline Surface Water (LSSW) (2) Tsushima Surface water (TSW) (3) Tsushima Middle Water (TMW) (4) North Korea Cold Water (NKCW) and (5) East Sea Proper Water (ESPW). In winter, surface water in coastal sea of Kwangwaan Kosung region were dominated by North Korean Cold Water (NKCW). As Tsushima warm current were enforced in summer, various water masses were vertically emerged in study area, in order of TSW, TMW, NKCW and ESPW. It is highly possible that the LSSW which occurred at surface water of september is originated from influx of fresh water due to the seasonal rainy spell. Nevertheless water masses existed within surface water were seasonally varied, water quality characteristics of East Sea Proper Water (ESPW) under 300 m did not changed all the seasons of the year.

• Journal of Microbiology and Biotechnology
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• 제22권10호
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• pp.1412-1422
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• 2012

The aim of this work was to establish the optimal conditions for production of carboxymethylcellulase (CMCase) by a newly isolated marine bacterium using response surface methodology (RSM). A microorganism producing CMCase, isolated from seawater, was identified as Cellulophaga lytica based 16S rDNA sequencing and the neighborjoining method. The optimal conditions of rice bran, ammonium chloride, and initial pH of the medium for cell growth were 100.0 g/l, 5.00 g/l, and 7.0, respectively, whereas those for production of CMCase were 79.9 g/l, 8.52 g/l, and 6.1. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ for cell growth were 6.25, 0.62, 0.28, and 0.42 g/l, respectively, whereas those for production of CMCase were 3.72, 0.54, 0.70, and 0.34 g/l. The optimal temperature for cell growth and the CMCase production by C. lytica LBH-14 were $35^{\circ}C$ and $25^{\circ}C$, respectively. The maximal production of CMCase under optimized condition for 3 days was 110.8 U/ml, which was 5.3 times higher than that before optimization. In this study, rice bran and ammonium chloride were developed as carbon and nitrogen sources for the production of CMCase by C. lytica LBH-14. The time for production of CMCase by a newly isolated marine bacterium with submerged fermentations reduced to 3 days, which resulted in enhanced productivity of CMCase and a decrease in its production cost.

• 대한환경공학회지
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• 제39권8호
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• pp.470-477
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• 2017

본 연구에서는 유기물 및 영양염류로 오염된 해양퇴적물 정화를 위한 석회석, 모래, 제올라이트 피복 공법의 적용성을 평가하였다. 수조 실험을 위한 퇴적물 및 해수 시료는 평택항에서 채취하였으며, 채취된 시료 위에 석회석, 모래, 제올라이트를 1 cm 또는 3 cm 두께로 피복하였다. 63일 동안 수층의 수소이온 농도(pH), 전기전도도(EC), 용존 산소(DO), 화학적 산소 요구량(COD), 총질소(TN), 총인(TP)을 측정하였다. 평택항 퇴적물을 분석한 결과 유기물과 총질소 오염이 높게 나타났다. 미피복 수조에서는 실험 시작 후 10일 이내에 DO가 고갈되었지만, 제올라이트 3 cm 피복을 제외하고 모든 피복 조건에서는 실험 기간 동안 용존 산소는 2 mg/L 이상 유지되었다. COD의 용출 차단 효율은 제올라이트 1 cm > 석회석 1 cm > 석회석 3 cm > 모래 3 cm ${\cong}$ 제올라이트 3 cm ${\cong}$ 모래 1 cm 순으로 나타났다. 질소의 용출 차단에는 제올라이트 피복이 효과적이었다. T-P는 미피복 및 피복 수조 모두에서 나타나지 않았다. 본 연구 결과 제올라이트는 유기물 및 질소 농도가 높은 오염퇴적물 정화를 위한 피복 소재로서 활용될 수 있을 것으로 판단된다.

• 지질공학
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• 제20권1호
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• pp.1-12
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• 2010

본 연구에서는 인천 해안 LPG공동의 수리화학적 안정성을 평가하기 위해 공동 유출수 및 주변 지하수에 대한 수리지구화학적 및 미생물학적 특성을 평가하였다. 수질특성을 파악하기 위하여 2007년 2월, 5월, 8월, 10월에 걸쳐 시료채취 및 수질분석을 실시하였다. 프로판공동 지하수의 경우 pH는 8.1~12.4의 높은 값을 보였으며 이는 공동건설 및 관측정설치에 사용된 시멘트 그라우팅 물질의 용해영향으로 사료된다. 전기전도도는 시료채취 시기별로 큰 차이를 보였으며, 음의 산화환원전위는 유출수 및 지하수가 환원환경에 있음을 지시하였다. 수질분석결과 유출수 및 지하수의 수질유형은 모두 Na-Cl type으로 나타났으며 이는 해수의 영향으로 판단된다. 호기성세균, 혐기성세균, 점액질세균, 황산환원세균 모두 500 CFU/mL 미만으로 낮은 값을 보였으며 급격한 미생물 성장은 관찰되지 않았다. 현재로선 공동 운영에 지장을 주는 특이적 수리화학적 현상이 발견되지는 않았으나 지속적인 모니터링이 필요하다.

• Ocean and Polar Research
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• 제29권4호
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• pp.349-366
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• 2007

Seasonal variations of various physicochemical components (temperature, salinity, pH, DO, COD, DOC, nutrients-silicate, DIN, DIP) and potential limiting factor for phytoplankton primary production were studied in the surface water of semi-enclosed Masan Bay. Seasonal variations of nutrient concentrations, with lower values in summer and winter, and higher in fall, are probably controlled by freshwater loadings to the bay, benthic flux and magnitude of occurrence of phytoplankton communities. Their spatial distributional patterns are primarily dependent on physical mixing process between freshwater and coastal seawater, which result in a decreasing spatial gradient from inner to outer part of the bay. In the fall season of strong wave action, the major part of nutrient inputs (silicate, ammonium, dissolved inorganic phosphorus) comes from regeneration (benthic flux) at sediment-water interface. During the summer period, high Si:DIN and Si:DIP and low DIN:DIP relative to Redfield ratios suggest a N- and secondarily P-deficiency. During other seasons, however, silicate is the potential limiting factor for primary production, although the Si-deficiency is less pronounced in the outer region of the bay. Indeed, phytoplankton communities in Masan Bay are largely affected by the seasonal variability of limiting nutrients. On the other hand, the severe depletion of DIN (relatively higher silicate level) during summer with high freshwater discharge probably can be explained by N-uptake of temporary nanoflagellate blooms, which responds rapidly to pulsed nutrient loading events. In Masan Bay, this rapid nutrient consumption is considerably important as it can modify the phytoplankton community structures.

• 한국수산과학회지
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• 제28권6호
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• pp.812-813
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• 1995

Lactococcal cells are nutritionally fastidious and thus, generally cultured either in milk or M17 medium (Terzaghi and Sandine, 1975). In this study, Lactococcus cremoris wild-type (KH) and its less­proteolytic mutant (KHA1) cells were grown on the M17 medium or with modified M17 medium by replicated parallel experiments. The modified M17 medium had the same composition as M17 medium, except that lactose was replaced by glucose. Analyses of culture-broth samples, in which the M17 and the modified M17 media were used, were conducted by high-performance liquid chromatography (HPLC). But, working with these media created noisy problems in analyses of samples. Therefore, a new semi-synthetic medium was developed on the basis of nutritional requirements (Morishita et al., 1981). The composition of the semi-synthetic medium determined on the basis of the nutritional requirements and the composition of milk, is presented in Table 1. The composition of M17 medium is also presented and compared in the table. L. cremoris KH and KHA1 cells were grown again on the new synthetic medium containing glucose or lactose. The broth samples were then drawn and analyzed by HPLC. Clearer separations of fermented products were achieved from the new medium than those with the M17 and the modified M17 media. In comparison with the M17 or the modified M17 media, growth on the new medium was good (Kim et al, 1993). Additional fermentations were also carried out at a controlled pH of 7.0, where enhanced growth of lactococcal cells was obtained. In the fermentations, samples were also analyzed for the concentrations of sugar and lactic acid. The results showed that the new synthetic medium was as good as or better than the M 17 and the modified M 17 media. This is because casein hydrolysate in the synthetic medium provided a ready supply of amino acids and peptides for L. cremoris KH and KHA1 cells. Lactic acid bacteria (LAB) including Lactococcal cells have been known to be an effective means of preserving foods, at the same time as giving particular tastes in fields of dairy products. LAB also have always occupied an important place in the technology of sea products, and marine LAB have known to be present in traditional fermented products (Ohhira et al, 1988). To apply the new synthetic medium to marine LAB, two different LAB were isolated from pickled anchovy and pollacks caviar and were grown on the new media in which various concentrations of NaCl $(3, 5, 7 and 10\%)$ added. They were also grown on the medium solution in natural seawater $(35\%o\;salinity)$ and on the solution of natural seawater itself, too. As seen in Fig. 1, Marine LAB were grown best on the synthetic medium solution in natural seawater and the higher concentrations of NaCl were added to the medium, the longer lag-phase of growth profile appeared. Marine LAB in natural seawater were not grown well. From these results, the synthetic medium seems good to cultivate cells which are essential to get salted fish aged. In this study, it showed that the new synthetic medium provided adequate nutrition for L. cremoris KH and KHA1 cells, which have been used as cheese starters (Stadhouders et al, 1988). Using this new medium, the acid production capability of starter cultures could be also measured quantitatively. Thus, this new medium was inferior to the M17 or the modified M17 medium in culturing the cheese starters and in measuring fermentation characteristics of the starter cells. Moreover, this new medium found to be good for selected and well-identified marine LAB which are used in rapid fermentations of low-salted fish.

• Ocean and Polar Research
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• 제28권2호
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• pp.79-94
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• 2006

가막만에 분포하는 동물플랑크톤의 종조성과 분포 양상을 밝히고, 군집에 미치는 환경요인을 파악하기 위해 2003년 4월, 7월, 9월, 11월에 총 12개 정점에서 조사하였다. 동물플랑크톤은 총 43개의 분류군이었으며 평균 출현 개체수는 $270{\sim}1,803$ 개체/$m^3$의 범위를 보였지만 시 공간적인 변동폭이 다소 크게 나타났다. 우점종은 요각류 A. erythraea, E. pacifica, A. omorii, P. par편 s. 1, 지각류인 P. polyphemoides이었다. 동물플랑크톤 군집은 3개의 Group으로 구분되어졌으며, 정체성 해역인 소호 인근의 Group A, 가막만 중앙부해역인 Group B, 비교적 해수 소통이 원활한 남부해역인 Group C로 구분되었다. 군집으로 구분되는 세 Group간에 종수와 다양성 지수는 군집에 유의한 영향을 미치는 것으로 나타난 반면(p<0.05), 평균출현 개체수는 유의한 영향을 미치지 않았다(p>0.05). 본 연구에서 조사된 환경 자료를 이용하여 분석한 결과 동물플랑크톤의 군집에 미치는 환경요인을 분석한 결과는 수온, 염분, 용존산소로 나타났다. 결과적으로 가막만 동물플랑크톤의 군집 특성을 볼 때 소호 인근 해역은 급속한 산업화와 도시화로 인하여 지속적인 생활하수의 유입의 영향을 받고 있으며, 남부 해역의 군집은 계절에 따른 만 외수의 영향을 받아 계절에 따른 군집양상이 바뀌는 것으로 판단된다.

• 한국환경농학회지
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• 제7권2호
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• pp.102-110
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• 1988

대호(大湖) 방조제(防潮堤) 축조(築造) 후(後) 담수호(淡水湖)의 수질(水質)을 조사(調査)하여 염농도 및 일반수질변화가 관개용수원에 미치는 영향을 규명(糾明)하고자 '84년(年) 에서 '88년(年) 5월(月) 까지의 조사결과(調査結果)를 요약(要約)하면 다음과 같다. 1. 대호(大湖) 담수호(淡水湖)의 수온분포(水溫分布)는 암거탄구 설치지점(設置地點)인 -14m 상부에는 계절변화(季節變化)에 따른 기온(氣溫)의 영향으로 변화(變化)$(6-25^{\circ}C)$가 많았으며, 암거탄구 이하에서는 $11.9^{\circ}C$로 년중(年中) 변화(變化)가 없었다. 2. 방조제(防潮堤) 앞 제일 깊은곳의 연도별(年度別) 수질변화는 pH7.6 $EC16,800-1,472{\mu}m$ hos/cm, DO 9.2-10.8ppm, BOD 1.3-2.5ppm, COD 2.4-5.3ppm, T-N 0.22-2.29pp, T-P는 0.01-0.10ppm을 나타내었다. 3. 대호(大湖) 담수층(淡水層)의 평균 수질성적('88년)은 pH 7.6, $EC1,745{\mu}m$ hos/cm, DO 10.8ppm, BOD 1.8pp, COD 2.4pp, T-N 0.52ppm, T-P 0.05ppm으로 전(全) 지점(地點)에서 비슷한 경향(傾向)이었다. 4. 담수층(淡水層)(6m)에서의 염도변화(鹽度變化)는 체절(締切) 전(前) 29,000ppm에서 '84년(年) 3월(月) 11,000ppm '85년(年) 3월(月) 4,300ppm, '86년(年), '87년(年) 3월(月)에는 2,000ppm, '88년 3월(月)에는 900ppm 까지 낮아졌다. 호내(湖內) 평균(平均) 염도(鹽度) 29,000ppm 정도에서 '88년(年) 3월(月) 1,200ppm 까지 낮아졌다. 또한 암거탄구 상부의 평균염도('87년(年))는 1,300ppm 정도였으며, 탄구아래는 해수(海水)와 같은 30,000ppm정도였다. 5. 담수층(淡水層)에서 가장 높은 염도를 나타낸 지점(地點)은 방조제(防潮堤) 앞 부근이며, '84년(年)에는 5,835ppm 이었다. 6. 조사시기별(調査時期別) 염도변화(鹽度變化)는 갈수기인 '87년(年) 5월(月) 2,000ppm에서 홍수기 후 8월(月) 800ppm, 풍수기인 9월(月)에는 485ppm까지 낮아졌다. 7. 염분약층(鹽分躍層) 깊이는 암거탄구 지점(地點)인 -l4m까지 유지(維持)되어 담수호화(淡水湖化)가 진행(進行)되었다. 그러므로 대호(大湖) 담수층(淡水層)의 수질은 농업용수원(農業用水源)으로는 큰 문제가 없으며, 삽교호로부터 제염용수(除鹽用水)의 공급(供給)도 불필요할 것으로 사료된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.473-476
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• 2004

In this study, hydrochemical studies of thermal waters in the Bugok and Magumsan areas showing geothermal anomalies were carried, and the applicability of ion seothermometers and multiple mineral equilibrium approach was examined to estimate their potential deep reservoir temperatures. Typical thermal waters of the two areas are clearly grouped into two major types, according to water chemistry: Na-Cl type (group A) and Na-SO4 type (group D). Compared to group A, group B and C waters show some modifications in chemistry. Group E waters show the modified chemistry from group D. Geothermal waters from the two areas showed some different chemical characteristics. The thermal waters of group A and B in Magumsan area are typically neutral to alkaline (pH=6.7 to 8.1) and Cl-rich (up to 446.1 mg/L), while the waters of group D and E in Bugok area are alkaline (pH=7.6 to 10.0) and SO$_4$-rich (up to 188.0 mg/L). The group A (Na-Cl type) and group D (Na-SO$_4$ type) waters correspond to mature or partially immature water, whereas the other types are immature water. The genesis of geothermal waters are considered as follows: group A and B waters were formed by seawater infiltration into reservoir rocks along faults and fracture zones and possibly affected by fossil connate waters in lithologic units through which deep hot waters circulate; on the other hand, group D and E waters were formed by the oxidation of sulfide minerals (mainly pyrite) in surrounding sedimentary rocks and/or hydrothermal veins occurring along restricted fracture channels and were possibly affected by the input and subsequent oxidation of S-bearing gases (e.g. H2S) from deep thermal reservoir (probably, cooling pluton). The application of quartz, Na-K, K-Mg geothermometers to the chemistry of representative group A and D waters yielded a reasonable temperature estimate (99-147$^{\circ}C$ and 90-142$^{\circ}C$) for deep geothermal reservoir. Aqueous liquid-rich fluid inclusions in fracture calcites obtained from drillcores in Bugok area have an average homogenization temperature of 128$^{\circ}C$, which corresponds to the results from ion geothermometers. The multiple mineral equilibrium approach yielded a similar temperature estimate (105-135$^{\circ}C$ and 100-14$0^{\circ}C$). We consider that deep reservoir temperatures of thermal waters in the Magumsan and Bugok areas can be estimated by the chemistry of typical Na-Cl and Na-SO$_4$ type waters and possibly approach 105-135$^{\circ}C$ and 100-14$0^{\circ}C$.

• 미생물학회지
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• 제51권4호
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• pp.364-373
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• 2015

알긴산의 응용을 위하여 인천지역에서 수집한 다양한 패류와 해수로부터 알긴산 분해효소 활성이 우수한 103개의 균주를 분리하고 그 중 M1-2-1, M6-1, C8-15 등 분해능이 가장 우수한 3균주를 선발하여 그 특성을 분석하였다. 이들은 모두 그람 음성 간균이었고, 운동성이 있는 호염성 세균이었다. 또한 생리 생화학적 특성 분석과 16S rRNA 유전자의 염기서열 분석으로 M1-2-1과 M6-1은 Pseudoalteromonas 속, C8-15은 Vibrio 속에 속하는 세균으로 동정되었다. 이들의 알긴산 분해효소 활성은 알긴산이 유일한 탄소원인 APY 배지에 접종하여 $25^{\circ}C$에서 6-8시간 배양했을 때 최대로 나타났고, NaCl을 가했을 때 생장 및 효소 활성 모두 증진되었다. 이 분리 균주들의 알긴산 분해 조효소들은 $45^{\circ}C$와 pH 7.0-8.0에서 가장 높은 활성을 나타냈으며, Pseudoalteromonas sp. M1-2-1과 M6-1 균주는 각각 2.7232 g/L와 1.976 g/L의 환원당 생성능을 보여, 산업적으로 활용 가능성이 높은 것으로 사료되었다.