• Food Industry
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• s.45
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• pp.32-37
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• 1978

자연에서 얻어지는 고무질로서는 여러 가지 종류의 것이 많으나 한천, 알긴산염, 카라기난(Carrageenan), 퍼셀라란(furcellaran)등은 해조로부터 추출되며 Pectin, arabic gum, karaya gum, tragacanth gum, ghatti gum, guargum, 메뚜기콩고무(Locust been gum), 사이리엄고무(psyllium seed gum)등은 식물로부터 추출된다. 특히 이외에도 미생물에서 분비되는 고무질인 다당(多糖)으로는 dextran, curdlan, pullulau, 잔산고무(Xanthan gum)등도 최근에 알려진 고무질이다. 여기에서는 미생물이 생산하는 고무질인 다당(多糖)인 Xanthan gum이 새로히 식품첨가물로 지정되었기에 Xanthan gum의 발견내역, 성질, 생산과 응용면을 소개한다.

• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.273-282
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• 2004

The synthetic technology of improved polyaluminiumchloride (IPAC) similar to characteristics of PACS was established with minimum expense for modifying existing production line. The conditions for activating silicate was studied before the synthesis of IPAC, and the IPAC was synthesised with raw materials such as aluminumhydroxide and concentrated hydrochloric acid, followed by adding activated silicate and alginate. The specification of product, chemical structure, and coagulating properties were tested by using specification testing method, instrumental analytical method, and Jar tester, respectively. As a result, the product, IPAC, contained aluminium oxide content more than 17%, and no precipitation was shown at all while the IPAC solution was preserved, and the larger floc and faster coagulation were represented compared to existing PAC under the same conditions. It was suggested that these synthetic technology could be applied to the existing production line for producing PAC without approximately cost raising factor because of adding sulfuric acid-activated silicate instead of sodium sulfate.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.313-318
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• 2004

We studied a storage of waste-brown seaweed at room temperature and degradation of alginate in seaweed by microorganism DS-02. The seaweeds, mixed with 5.0 wt% DS-02 and sealed in vinyl package without any other treatment, could be stored longer than 1 year without spoilage at room temperature. During the storage process, the alginate of seaweed was decomposed by enzyme of DS-02 and the molecular weight of alginate decreased to about 1/10 of initial quantity. DS-02 growed as fast as it had maximum weight after 24 hour culture and it's enzyme had a maximum activity of alginate degradation at $40^{\circ}C.$ The seaweed sample became particles in DS-02 culture solution and the M. W of alginate decreased to about 1/10 of initial value after 24 hour decomposition. The effect of alginate degradation with DS-02 was similar to that of degradation with 3.0 M HCI solution for 24 hour.

• Journal of Environmental Science International
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• v.13 no.12
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• pp.1139-1144
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• 2004

We studied a extraction and degradation of alginate from seaweed-stems using microorganism DS-02. DS-02 has a maximum growth rate at $30^{\circ}C$ and the enzyme has a maximum activity of alginate extraction at $35^{\circ}C.$ The yield of alginate extraction using DS-02 is about $16.0{\%}$ for 3.0 hour and molecular weight of the alginate decreased to about 1/8 of initial value after 24 hour extraction. Alginate extraction method by DS-02, compared with general alkali-extraction method, has an advantage of decreasing the molecular weight of alginate during extraction.

• KSBB Journal
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• v.17 no.1
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• pp.63-67
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• 2002

Silver-alginate and copper-alginate were prepared with Na-alginate extracted from marine brown algae(Sargassum fluitans). The antibacterial effect of Ag-alginate or Cu-alginate against Staphylococcus aureus and Escherichia coli was carried out by measuring optical density of liquid culture at 600 nm. The cell growth of Staphylococcus aureus and Escherichia coli was very active at pH 7, and was inhibited by adding Ag-alginate with more than 0.006 wt.% of silver content. The antibacterial effect of Ag-alginate against S. aureus and E. coli was better than that of Cu-alginate at the same metal concentration. The cell growth of S. aureus was less inhibitory than E. coli at the same concentration of Ag-alginate. The cell growth of S. aureus and E. coli was also influenced by the characteristics of counter ion of silver.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.205-214
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• 2020

Cyanobacteria are microorganisms which have important roles in the nitrogen cycle due to their ability to fix nitrogen in water and soil ecosystems. They also produce valuable materials that may be used in various industries. However, some species of cyanobacteria may limit the use of water resources by causing harmful algal blooms in water ecosystems. Many culture collection depositories provide cyanobacterial strains for research, but their systematic preservation is not well-developed in Korea. In this study, we developed a method for the cryopreservation of the cyanobacteria Trichormus variabilis (syn. Anabaena variabilis), using alginate microcapsules. Two approaches were used for the experiments and their outputs were compared. One of the methods involved the cryopreservation of cells using only a cryoprotectant and the other used the cryoprotectant within microcapsules. After cryopreservation for 35 days, cells preserved with both methods were successfully regenerated from the initial 1.0 × 10⁵ cells/ml to a final concentration of 6.7 × 10⁶ cells/ml and 1.1 × 10⁷ cells/ml. Irregular T. variabilis shapes were found after 14 days of regeneration. T. variabilis internal structures were observed by transmission electron microscopy (TEM), revealing that lipid droplets were reduced after cryopreservation. The expression of the mreB gene, known to be related to cell morphology, was downregulated (54.7%) after cryopreservation. Cryopreservation using cryoprotectant alone or with microcapsules is expected to be applicable to other filamentous cyanobacteria in the future.