• ALGAE
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• 제33권1호
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• pp.1-19
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• 2018

Members of the family Parviluciferaceae (Alveolata, Perkinsozoa) are the well-known dinoflagellate parasitoids along with Amoebophrya ceratii species complex and parasitic chytrid Dinomyces arenysensis and contain six species across three genera (i.e., Parvilucifera infectans, P. sinerae, P. rostrata, and P. corolla, Dinovorax pyriformis, and Snorkelia prorocentri) so far. Among Parvilucifera species, the two species, P. infectans and P. sinerae, are very similar or almost identical each other morphologically and genetically, thereby make it difficult to distinguish between the two. The only main difference between the two species known so far is the number of sporangium wall (i.e., 2 layers in P. infectans vs. 3 layers in P. sinerae). During sampling in Masan bay, Korea during the spring season of 2015, the dinoflagellate Akashiwo sanguinea cells infected by the parasite Parvilucifera were observed and this host-parasite system was established in culture. Using this culture, its morphological and ultrastructural features with special emphasis on the variation in the number of sporangium wall over developmental times, were investigated. In addition, the sequences of rDNA regions and ${\beta}-tubulin$ genes were determined. The result clearly demonstrated that the trophocyte at 36 h was covered with 4 layers, and then outer layer of the sporocyte gradually degraded over time, resulting in wall structure consisting of two layers, with even processes being detached from 7-day-old sporangium with smooth surface, indicating that the difference in the number of layers seems not to be an appropriate ultrastructural character for distinguishing P. infectans and P. sinerae. While pairwise comparison of the large subunit rDNA sequences showed 100% identity among P. infectans / P. sinerae species complex, genetic differences were found in the small subunit (SSU) rDNA sequences but the differences were relatively small (11-13 nucleotides) compared with those (190-272 nucleotides) found among the rest of Parvilucifera species (P. rostrata and P. corolla). Those small differences in SSU rDNA sequences of P. infectans / P. sinerae species complex may reflect the variations within inter- strains of the same species from different geographical areas. Taken together, all morphological, ultrastructural, and molecular data from the present study suggest that they are the same species.

• 한국식생활문화학회지
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• 제27권2호
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• pp.211-224
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• 2012

Eggplant pickles were classified into three groups based on salt concentration (1, 3, 5%) and three groups based on drying time (30, 60 and 120 minutes), followed by storage at $5^{\circ}C$ for 28 days. Raw eggplant contains 94.82% water content. The increase in salt concentration and drying time caused a decrease in the moisture content. Compared to the 0.27% ash content of raw eggplant, the ash content of eggplant pickles increased noticeably with increasing salt concentration due to penetration into the eggplant pickles. pH values decreased significantly as the levels of salt concentration and dying time increased (p<0.05). In terms of storage time, pH values decreased from 21 days. The variation in salinity increased significantly as the concentration of salt increased. Compared to normal pickles salted at 5.39% salinity, eggplant pickles constituted 0.27~0.77% (1%), 0.40~1.14% (3%), and 0.47~11.20% (5%) 'low-salinity' eggplant pickles. Reducing-sugar content differed on the dates of 7, 14 and 21 in drying time and at 3% salinity. Hardness differed at 30, 60, and 120M on the 28th and 1, 5% salt concentration. Resilience differed according to drying time and from dates of 0 to 14th. The number of total microbes decreased at low salinity. In terms of storage time, the number of microbes tended to decrease after the 21st. In the consumer preference test, lightness of 5%-30M was the highest value.

• 한국축산식품학회지
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• 제41권4호
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• pp.636-649
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• 2021

The aim of this study was to evaluate the effect of three different strains of lactic acid bacteria (LAB) starter cultures: Pediococcus pentosaceus (KC-13100) (PP), Lactobacillus plantarum (KCTC-21004) (LP1), and L. plantarum (KCTC-13093) (LP2) on the physicochemical and microbiological characteristics, and sensory quality of dry fermented sausages after 21 days of drying and ripening period. Treatments added with PP and LP2 strains showed a significant higher (p<0.05) LAB and total plat counts, and water activity (a_w) of all three treatments was below 0.85 after the completion of the ripening process. A significant variation (p<0.05) in pH values of treatments was exhibited due to the difference in acidification capacity of the LAB strains: LP2PP>LP2. Substantial variations (p<0.05) in shear force values were detected amongst three batches (LP2>LP1>PP). In sensory attributes, PP treated samples had significantly higher (p<0.05) color and overall acceptability scores. The current findings proved how important the optimal assortment of starter culture. Inoculation with PP produced importantly beneficial effects on sensory quality improvement of dry fermented sausage.

• 한국유기농업학회지
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• 제22권4호
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• pp.743-760
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• 2014

본 연구는 유기농업에서 생물자원으로서 담수 클로렐라의 활용 가능성을 연구하고자 유기농 생태계로부터 담수 녹조류를 분리, 동정하고, 생물학적인 특성을 조사하였다. 조사 지역의 수온은 $12.4{\sim}28.2^{\circ}C$, pH는 6.1~8.5이었다. 담수 녹조류를 분리할 때 고체배양법이 액체배양법보다 오염도가 낮고 분리 빈도가 높았다. 전국 9개 지역, 6개 담수 녹조류 서식처로 부터 총 115개의 균주를 분리하였다. 담수 녹조류의 분리 및 배양을 위해 질소원으로는 $NaNO_3$과 $KNO_3$, 탄소원으로 $Na_2CO_3$를 사용하였고, macro media의 구성 성분 중 $MgSO_4{\cdot}7H_2O$과 $CaCl_2{\cdot}2H_2O$를 분리하여 제조한 BGMM(BG11 Modified Medium)배지를 고안하였다. 담수녹조류는 배양 후 4일째부터 급격히 흡광도가 증가하였고 8일째부터 흡광도가 감소하였다. 공시한 7개의 균주 중 CHK008 균주가 배양 7일째에 가장 높은 흡광도를 보였다. 담수 녹조류 배양에 적합한 BGMM 배지의 pH는 6~7이었고 조사되는 빛이 강할수록 생육이 증가하였으며 5종류 당류 중에서 Glucose와 Galactose를 첨가하였을 때 클로랄라의 생육이 좋았다. 순수 분리한 16개 녹조류 균주의 균총색은 녹색, 진녹색, 연녹색을 나타내었고, 11개의 균주가 형광현미경하에서 강한 형광 빛을 나타내었다. 녹조류 16개 균주의 형태적인 특징을 조사한 결과 C. vulgalis, C. sorokiniana, C. pyrenoidosa, C. kessleri, C. emersonii, and Chlamydomonas sp.의 2개 속 6개종으로 동정되었다. 담수 녹조류의 세포 크기는 종마다 다양한 변이를 보였다. 대부분의 담수 녹조류의 세포형태는 구형이었다. Chlamydomonas sp.는 타원형이었고 Chlorella sorokiniana는 구형과 타원형이 섞여 있었다. 6개 녹조류 종류 중 Chlamydomonas sp.를 제외한 모든 균주는 편모가 없었다. Chlamydomonas sp. 1개 균주와 C. sorokiniana 5개 균주는 세포에서 점질물을 분비하였다.

• Journal of Microbiology and Biotechnology
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• 제21권3호
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• pp.267-273
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• 2011

Methyl violet, used extensively in the commercial textile industry and as a biological stain, is a hazardous recalcitrant. Aspergillus sp. strain CB-TKL-1 isolated from a water sample from Tsumoriri Lake, Karzok, Ladakh, India, was found to completely decolorize methyl violet within 24 h when cultured under aerobic conditions at $25^{\circ}C$. The rate of decolorization was determined by monitoring the decrease in the absorbance maxima of the dye by UV-visible spectroscopy. The decolorization of methyl violet was optimal at pH 5.5 and $30^{\circ}C$ when agitated at 200 rpm. Addition of glucose or arabinose (2%) as a carbon source and sodium nitrate or soyapeptone (0.2%) as a nitrogen source enhanced the decolorization ability of the culture. Furthermore, the culture exhibited a maximum decolorization rate of methyl violet after 24 h when the C:N ratio was 10. Nine N-demethylated decolorized products of methyl violet were identified based on UV-visible spectroscopy, Fourier transform infrared (FTIR), and LC-MS analyses. The decolorization of methyl violet at the end of 24 h generated mono-, di-, tri-, tetra-, penta-, and hexa-N-demethylated intermediates of pararosaniline. The variation of the relative absorption peaks in the decolorized sample indicated a linear decrease of hexa-N-demethylated compounds to non-N-demethylated pararosaniline, indicating a stepwise N-demethylation in the decolorization process.

• 한국해양환경ㆍ에너지학회지
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• 제16권3호
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• pp.189-201
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• 2013

한산거제만 해역의 장기수질 특성을 알기 위해 1987년부터 2010년까지 만내 2개 정점에 대한 표 저층 수질에 대한 장기관측 자료를 분석하였다. 한산거제만 해역의 수질 영양수준은 중영양(Mesotrophic) 단계이고, 영양염은 대체로 하계인 8월부터 꾸준히 증가하여 갈수기인 11월에 최대 농도를 보인 후, 동계를 지나 이듬해의 춘계인 5월에 최저 농도가 되는 계절적 변동 특성을 보였다. 요인분석 결과 한산거제만은 영양염, 계절, 담수유입, 오염 및 내부생산 등의 5개 요인이 해역 수질 특성의 76.82%를 설명할 수 있는 것으로 나타났다. 시계열분석 결과 수온, DO 및 저층 DIP는 증가, pH 및 COD는 감소하는 경향을 보였다. 특히 N/P비를 기준으로 DIN의 변동 추세는 1990년대를 전 후하여 과잉에서 부족으로 전환되었다. 또한 한산거제만은 전형적인 폐쇄성 내만이며 대규모 양식이 이루어지고 있음에도 1987년 이후 DIP를 제외하곤 수질이 대체로 개선되고 있는 것으로 나타났다. 한산거제만 해역의 지속적 이용과 보존을 위해서는 DIP 증가 또는 축적의 원인 파악이 필요하며, 이를 위해 한산거제만의 주요 양식생물과 환경과의 상호관계 등에 대한 연구가 필요하다.

• KSBB Journal
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• 제11권3호
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• pp.303-310
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• 1996

해양 미세조류인 Isochrysis galbana Parke의 성장에 미치는 여러 환경요인과 배지요인의 영향을 조사하고 최적 배양조건을 구하였다. 그 결과를 요약하 면 다음과 같다. 1. 인공바닷물은 자연바닷물보다 다소 낮은 비성 장속도와 최종 균체농도를 나타내었다. 2.. 자연바닷물이 기초배지로 사용되었을 때 2mM 이상의 충분한 질산염 농도가 필요하였다. 그러나 미량원소와 비타민의 영향은 관찰되지 않았다. 3. 완충용액요로 Tris를 첨가한 경우 pH는 일정 하게 유지가 가능하나 비성장속도와 최종 균체농도 가 감소하였다. 4. 최적 초기 pH와 온도는 각각 pH 8, $20^{\circ}C$ 였다. 5. 벚세기를 400-21001ux의 범위에셔 변화시켰을 때 비성장속도는 18501ux까지 증가하였고 그 이 후로는 일정하였다. 6. 10mL에서 70mL로 Working volume을 증가 시켰을 때 초기 성장속도는 비슷하였으나 최종 균체 농도가 감소하는 경향을 보였다. 7. Working volume이 30mL일 때 최적 교반속 도는 100rpm정도이고, 더 높은 교반속도에서는 최 종 균체농도의 감소가 관찰되었다. 8. 플라스크배양의 최적조건에서 최대 비성장속도 와 최종 균체농도는 각각 $O.021hr^{-1}$과 1.1g/L로 얻어졌다.

• 한국염색가공학회지
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• 제11권2호
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• pp.19-26
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• 1999

Strains degrading and decolorizing acid dyes, Nylosan red E-BL 150%. were isolated from natural system, was named as ARK3. The optimal culture conditions of temperature and pH were $35^\circ{C}$, 7.0, respectively. Growth rate of cells in conditions of aerobic shaking more than standing culture conspicuously increased, and optical density of those to strain ARK3 were found as 1.38 and 0.25 after 42 hrs. Decolorization efficiency in batch culture which used as immobilization media to natural zeolite was 15% after 6 hrs, while suspension culture was 5%, also its of immobilization and suspension culture were 90% and 85% after 48 hrs, respectively. Decolorization efficiency of air-lift bioreactor was more than 90% to a dilution rate of $0.038hr^{-1}$, but that was decreased as 70%, when the dilution rate was $0.05hr^{-1}$. Even though at maximum dilution rate of this study, there was not appeared "wash out" phenomienon of biomass. Decolorization efficiency was 97.7% at a dilution rate of $0.025hr^{-1}$, when influent dye concentration was $100mg/\ell$. But if influent dye concentration increased as $150mg/\ell$, even though MLVSS increased, that of treatment water decreased as 93%. Also, when influent dye concentration increased as $200mg/\ell$ and $300mg/\ell$, decolorization efficiencies of treatment water abruptly decreased as 85% and 63%, respectively. Decolorization efficiency was more than 92% to the limit volumetric loading rate of $3.75mg/\ell\cdot{hr}$hr, without regard to variation of influent dye concentration or hydraulic retention time. if volumetric loading rate was more than $3.80mg/\ell\cdot{hr}$, at same condition, decolorization efficiency was lower decrease of retention time than increase of influent dye concentration.entration.

• International Journal of Advanced Culture Technology
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• 제8권2호
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• pp.252-259
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• 2020

Wheatgrass is a type of young grass that contains a lot of vitamins, minerals, and protein even compared to grain products produced from its mature cereal plants. In the context of product development and increasing product sales value, a study on the use of wheatgrass extract as an ingredient of fermented beverage was conducted. In this study wheatgrass used was self-grown using a tray in the Laboratory. The variation of wheatgrass extracts used was obtained from the twin-gear type extractor, slow-squeeze type extractor, and chopped wheatgrass. In the extraction process, the performances of the process: density, extract yield, processing capacity, and the rate of production, were analyzed. For another analysis, the physicochemical properties both of wheatgrass extracts and fermented beverages were also analyzed. The physicochemical properties analyzed included TSS, pH, acidity, and others content. The results of extraction performance analysis and physicochemical characteristics of wheatgrass extract planted at 10-20℃ based on this research gave the best results using the twin-gear extractor. The twin-gear type of extractor used in this study. All of these results were also in accordance with the statistical analysis conducted in this study.

• 환경생물
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• 제22권3호
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• pp.394-399
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• 2004

S. marcescens LSY4가 충전된 BOD센서를 제작하여 표준오염물질을 포함한 수용액의 BOD를 측정하였다. 배양시간이 9∼16시간일 때에는 배양시간에 따른 BOD센서의 감응도에 큰 차이를 나타내지 않았으며, 균체량도 0.22~0.75mg $cm^{-2}$의 범위에서는 거의 동일한 센서의 감응도를 나타내었다. 수용액의 pH가 4~9사이로 변화할 경우 센서의 감응도가 가역적으로 변화하였으나 수용액이 더 산성이거나 더 염기성이 되면 센서의 감응도가 비가역적으로 저하되었다. 수용액에 중금속이온이 첨가되면 센서의 감응도가 감소하였으며, $Zn^{2+}$나 $Cd^{2+}$보다 $Cu^{2+}$혹은 $Ag^+$가 첨가되었을 때 센서의 감응도가 더 급격히 감소하였다. 중금속에 대한 내성이 유도된 균체를 충전하였을 때 중금속이온의 첨가에 따른 센서의 감응도 감소가 크게 완화되었으며, 이런 효과는 $Cd^{2+}$내성주보다 $Cu^{2+}$내성주에서 더 현저하였다.