• Title/Summary/Keyword: 염농도

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내염성 미생물의 생태학과 산업적 이용 가능성

  • 조무제
    • The Microorganisms and Industry
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    • v.14 no.3
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    • pp.31-32
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    • 1988
  • 염농도는 미생물 생육에 중요한 환경요인의 하나로서 대부분의 미생물들은 염농도 1% 이내를 생육 최적조건으로 하지만 자연계에는 염농도 1% 이상에서 포화염농도까지 생육이 가능한 것들도 많다. 미생물 중에는 생육 최적염농도보다 높은 환경에 처하면 여러가지 적응기작에 의해 고염분 농도에 적응하면서 생육할 수 있는 내염성 미생물과 고염농도 환경을 생육 최적조건으로 하는 호염성 미생물로 대별할 수 있다.

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Quality Characteristics of Dombaegi(Salted Shark Meat) with Reference to Salt Concentration and Temperature during Dry Salting (염농도와 절임온도에 따른 돔배기의 품질특성)

  • Kim, Do-Hoon;Youn, Kwang-Sup
    • Food Science and Preservation
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    • v.16 no.5
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    • pp.656-660
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    • 2009
  • We investigated the quality characteristics of Dombaegi after drying, with respect to salt concentration (1%, 2%, 3% all w/v) and salting temperature ($4^{\circ}C$, $18^{\circ}C$), to establish optimum salting conditions. Changes in moisture and salt content, water holding capacity, water activity, color, and textual properties of salted Dombaegi were measured. The moisture content was highest in Dombaegi prepared with 3% (w/v) salt at 4C. The salt content of Dombaegi rose as salt concentration and temperature increased. The water holding capacity was greatest after salting with 3% (w/v) salt at $4^{\circ}C$. Color and texture were superior after preparation at higher salt concentrations and lower salting temperatures. Thus, the quality of Dombaegi was optimal when dry salting was performed at the highest salt concentration (3%, w/v) and the lower salting temperature ($4^{\circ}C$).

Effects of Salt Concentration on Motility and Expression of Flagellin Genes in the Fish Pathogen Edwardsiella tarda (염 농도가 어류 병원체 Edwardsiella tarda의 운동성과 편모발현에 미치는 영향)

  • Yu, Jong-Earn;Park, Jun-Mo;Kang, Ho-Young
    • Journal of Life Science
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    • v.21 no.10
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    • pp.1487-1493
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    • 2011
  • E. tarda, a fish pathogen, can survive in seawater under relatively high salt conditions as well as in fish under physiological salt conditions. Bacterial growth under different salt concentrations may influence the expression of genes involved in bacterial structure and physiology. The growth rate of E. tarda culture in high salt (3.5% NaCl) was similar to that in low salt (1.0% NaCl, physiological salt concentration). Interestingly, the strain moved much faster in low salt conditions than in high salt conditions. Electron microscopic observation demonstrated that the bacterial cells grown in high salt had less or no flagellation. Obvious flagellation was observed in the parental strain E. tarda CK41 grown in low-salt condition. Two putative genes coding flagellin were identified in the E. tarda genome sequences. The amino acid sequence comparison of each gene revealed 93% identities. A flagellin gene was PCR amplified and cloned into a cloning vector. Using an E. coli protein expression system, a part of flagellin protein was overexpressed. Using the purified protein, an anti-flagellin antibody was raised in the rabbit. Immunoblot analyses with flagellin specific antibody demonstrated that E. tarda CK41 expressed falgellin in low salt conditions, which is consistent with the results seen in motility assay and microscopic observation. This is the first report of salt regulated flagella expression in E. tarda.

Microbial Changes in Salted and Fermented Shrimp at Different Salt Levels during Fermentation (염농도를 달리한 새우젓 발효 중 미생물 변화)

  • Mok, Chul-Kyoon;Lee, Ju-Yeon;Park, Jong-Hyun
    • Korean Journal of Food Science and Technology
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    • v.32 no.2
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    • pp.444-447
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    • 2000
  • The microbial changes during the fermentation of salted and fermented shrimp at different salt levels $(3{\sim}30%)$ were investigated to elucidate the effect of salt on the microflora of the fermented shrimp. During 22 weeks of fermentation, the numbers of total bacteria and yeasts of the fermented shrimp with 3, 8, 30% salt generally decreased with fermentation time, while those in the fermented shrimp of 18% salt increased. Halophilic bacteria were found only in the late stage of the fermentation at 18% salt. The greatest number of the halophilic yeasts was observed also at 18% salt level. The results indicated that 18% salt provided the most favorable environment for the microorganisms related to the shrimp fermentation.

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Change in rheological properties of radish during salting (염 절임동안에 일어나는 무조직의 유변학적인 변화)

  • Kim, Byung-Yong;Cho, Jae-Sun
    • Applied Biological Chemistry
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    • v.35 no.5
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    • pp.399-403
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    • 1992
  • The amounts of salt diffused into radish after immersing in various concentrations of salt solution at different temperatures were measured and the changes of radish texture by the salt diffusion were estimatedwith the viscoelastic constants of a 3 element solid model determined by a stress relaxation test. While the amount of salt diffused throught radish was increased with increasing the salt concentration and soaking temperature, the istantaneous stress, equilibrium elastic solid and viscoelastic constants of radish were decreased. Also the degree of stress relaxation and equilibrium elastic solid approached the same or zero values, as salt concentration was further increased. Viscoelstic constants as well as salt diffusion were more influenced by lower salt concentration with increased temperatures.

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Growth and Physiological Characteristics in a Halophyte Suaeda glauca under Different NaCl Concentrations (염생식물 나문재의 염농도에 따른 생장 및 생리적 특성)

  • Kim, Ji-Young;Seong, Phil-Mo;Lee, Deog-Bae;Chung, Nam-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.1
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    • pp.48-54
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    • 2019
  • This research was carried out to investigate the plant growth, inorganic ion and amino acid content characteristics in a halophyte, Suaeda glauca, under different NaCl concentrations for cultivating in the reclaimed land. S. glauca was hydroponically cultivated under 0, 50, 100, 200, 300 and 400 mM NaCl concentrations with Hogland's nutrient solution. To evaluate growth response under different NaCl concentrations, plant height and number of branches, dry weight, Fv/Fm value, and photosynthetic efficiency were investigated. To find out physiological characteristic, inorganic ion contents and amino acids in the plant were evaluated. The optimum concentration of NaCl for plant growth were 50 mM. The plant growth were gradually decreased in the concentration ranged from 100 to 400 mM. As increasing of NaCl concentration, Na ion was increased, but K, Ca, Mg ions were decreased in the plant. The amino acid contents were varied due to NaCl concentrations, but most of amino acids content in total plant was the lowest at 50 mM. Conversely, proline was exceptionally high at 50 mM of NaCl concentration. The Fv/Fm value was the highest at 50 mM of NaCl concentration. From these results, the optimum salt concentration for the growth of S. glauca was 50 mM, but the plant seems to adapt in a variety of salt environments in view of the change of ions and amino acids depending on salt concentration and the maintenance of photosynthetic efficiency even under high salt condition.

Microbiological Characteristics of Low Salt Mul-kimchi (저염 물김치의 미생물균총 특성)

  • Oh, Ji-Young;Hahn, Young-Sook;Kim, Young-Jin
    • Korean Journal of Food Science and Technology
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    • v.31 no.2
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    • pp.502-508
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    • 1999
  • Microbiological characteristics of low salt Mul-kimchi was examined. Mul-kimchi was prepared by mixing of radish (25%), green onion (2.4%), red pepper (1.9%), garlic (1.9%) and salt (0, 0.2, 0.5, 1.0, 1.5, 2.0, 2.5, 2.5, 3.0%) in water and fermented at 4, 15 and $25^{\circ}C$ for 10 days, respectively. During fermentation period, total cell, Leuconostoc sp., Lactobacillus sp., Streptococcus sp., Pediococcus sp., coliform bacteria, gram (-) bacteria and yeast cell number were counted on their selection media. The microbes in Mul-kimchi were isolated and identified. Total cell number increased as salt concentration decreased and fermentation temperature increased. Lactic acid bacteria showed the highest number in 1.0% salt concentration. Yeast cell number increased with increase of salt concentration. Lactobacillus sp. were identified Lactobacillus plantarum and L. pentosus in Mul-kimchi containing $0.2{\sim}1.0%$ salt while those of Mul-kimchi containing 3.0% salt were Lactobacillus plantarum and L. brevis. The other lactic acid bacteria were identified Leuconostoc citrum, Leu.mes.ssp.mesenteroides/dextranicum and streptococcus facium in Mul-kimchi containing $0{\sim}3.0%$ salt while Pediococcus sp. was not detected. Gram-negative Aeromonas hydrophila, Pseudomonas fluorescens, Pseu. aureofaciens and yeast Candida pelliculosa, Cryptococcus laurentii were identified in the Mul-kimchi.

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Effect of NaCl Concentration and Fermentation Temperature on the Quality of Mul-kimchi (염농도 및 발효 온도가 물김치의 품질 특성에 미치는 영향)

  • Oh, Ji-Young;Hahn, Young-Sook
    • Korean Journal of Food Science and Technology
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    • v.31 no.2
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    • pp.421-426
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    • 1999
  • This study was conducted to examine the quality of low-salt Mul-kimchi which was prepared by mixing of radish (25%), green onion (2.4%), red pepper (1.9%), garlic (1.9%) and salt (0, 0.2, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0%) in water and followed by fermentation at 4, 15 and $25^{\circ}C$ for 10 days, respectively. The pH was lowest and acidity was highest in the Mul-kimchi containing 1.0% salt. The total vitamin C contents in Mul-kimchi containing $0{\sim}0.2%$ salt were high at the early stage of fermentation while those of Mul-kimchi containing 3.0% salt were higher than the low-salt samples after the optimal ripening time. The hardness of the radish increased with the salt concentration. Overall palatability of Mul-kimchi showed the highest score in 1.0% salt sample.

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A Mechanical Model for Texture Changes and Rheological Properties of Radish During Salting (염농도의 확산에 따른 무의 물성학적 특성의 예측 model에 관한 연구)

  • Lee, Seung-In;Kim, Byung-Yong;Cho, Jae-Sun
    • Korean Journal of Food Science and Technology
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    • v.24 no.4
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    • pp.335-340
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    • 1992
  • The amounts of salt diffused into radish after immersing in various concentrations of salt solution at different temperatures were measured and the changes of radish texture by the salt diffusion were estimated with the viscoelastic constants of a 3 element solid model determined by a stress relaxation test. The amount of salt diffused through radish was increased with increasing the salt concentration and soaking temperature. While the instantaneous stress, equilibrium elastic solid content and viscoelastic constants of radish were decreased as salt concentration and soaking temperature increased, the stress relaxed fast. Viscoelastic constants as well as the diffusivity were influenced by salt concentration more than by soaking temperature. The rheological equations for the predictable stress changes of radish after immersed in the salt solution at various conditions (temperature, salt concentration and impure salt) were suggested as a function of time.

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Adaptations and Physiological Characteristics of Three Chenopodiaceae Species under Saline Environments (명아주과 3종 식물의 염 환경에 대한 적응특성의 비교)

  • 송승달;김진아;추연식;배정진;김인숙;추보혜;이인중
    • The Korean Journal of Ecology
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    • v.25 no.2
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    • pp.101-107
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    • 2002
  • Three species of Chenopodiaceae, i.e. Suaeda japonica, Salicomia herbacea, Beta vulgaris var. cicla, were investigated to compare the physiological characteristics through inoic balances and osmoregulations under different environmental salt gradients. Plats were harvested in two weeks from treatments with salt gradients (0, 50, 100, 200 and 400 mM NaCl) and mineral nutrition gradients(1/1, 1/5, 1/10 dilutions of Hoagland solution). Plants were analyzed for growth responses, ionic balances, osmolalities, conductivities, glycinebetaine and proline contents quantitatively. Three plants of Chenopodiaceae accumulated slats into tissues unlike some salt sensitive species, and showed unique adaptation patterns to overcome saline environments, i.e. strong growth stimulation for Salicomia herbacea, growth negative tolerance for Suaeda japonica, and growth positive tolerance for Beta vulgaris var. cicla. The absorption of inorganic Ca/sup 2+/ ions was inhibited remarkably due to the excess uptake of Na+ with increasing salinity. The K+ content in plants was significantly reduced with increasing salinity. Total nitrogen content was reduced as mineral nutritions and salinity increased. Conductivity and osmolality increased with increasing salinity regardless of mineral nutritions. The ranges of glycinebetaine and proline contents were 0.2∼2.5 μM/g plant water and 0.1∼0.6μM/g plant water, respectively.