• 미생물학회지
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• 제31권3호
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• pp.179-183
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• 1993

A restricted facultatively methanol-oxidizing bacterium, Methylovorus sp. strain SS1, was isolate dfrom soil samples from Kuala Lumpur, Malaysia, through methanol-enrichment culture technique. The isolate was nonmotile Gram-negative rod and did not have complex internal membrane system. The colonies were small, pale-yellow, and raised convex with entire margin. The cell did not produce any spores and capsular materials. The cell was obligately aerobic and exhibited catalase, but no oxidase, activity. Plasmid, carotenoid pigment, and poly-.betha.-hydroxybutyric acid were not found. The guanine plus cytosine content of the DNA was 55%. The isolate was found to grow only on methanol methylamine, or glucose. Growth factors were not required. Cells growing on methanol was found to produce extracellular polysaccharides containing glucose, lactose, and fructose. Growth was optimal (t$_{d}$= 1.7) with 0.5%(v/v) methanol at 40.deg.C and pH 6.5. No Growth was observed at over 60.deg.C. Cell-free extracts of the methanol grown cells exhibited the phenazine methosulfate-linked methanol dehydrogenase activity Methanol was found to be assimilate dthrough the ribulose monophosphate pathway.y.

• 대한치과의사협회지
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• 제9권12호
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• pp.807-811
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• 1971

This report was concerned with the isolation and identification of bacterial flora in the human dental plaque and the dextransucrase activity of isolated species. The results were obtained as follows: 1. The bacterial flora, isolated from the human dental plaque, was identified as 3 species of resembling streptococci, Streptococcus salivarius strain SD-1, Streptococcus bacilli, Lactobacillus brevis strain SD-3, Lactobacillus acidophilus strain SD-2 and SD-7, resembling Staphylococcus sp, and one species of resembling Leuconostoc mesenteroides strain SD-6. 2. The dextransucrase activites of resembling Streptococcus mitis strain SD-9 and Streptococcus salivarius strain SD-1 were exhibited the highest among the isolated species of human dental plaque.

• Journal of Dairy Science and Biotechnology
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• 제40권1호
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• pp.48-56
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• 2022

Enterococcus species have been reported to produce unique flavoring ingredients in fermented dairy products. Generally, they were found in cheese and fermented dairy products. Enterococcus spp. produce extracellular polysaccharides and reduce blood cholesterol levels in humans. This study used heat-killed E. faecalis and E. faecium in yogurt production to increase safety during consumption. The addition of heat-killed E. faecalis and E. faecium to milk did not affect the fermentation time of yogurt production, the growth of starter cultures, and the viscosity of yogurt. These results concluded that heat-killed Enterococcus, rather than live Enterococcus, is sufficiently possible and even safer to be added to milk products. Enterococcus species could be used as a safe and functional food additive to fermented milk products and supplements in health foods.

• 한국산학기술학회논문지
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• 제12권10호
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• pp.4450-4458
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• 2011

본 연구는 다양한 탄수화물 아래에서 자일리톨 감성균주와 내성균주의 치아우식과 관련된 특성을 비교해보고자 하였다. 이를 위하여 1% 자일리톨이 첨가된 TYE 배지에서 S. mutans를 30일간 배양하여 자일리톨 내성균주를 형성하였으며, 이후 0.5% 포도당이 포함된 배지에 자당, 과당, 엿당을 첨가하여 성장, 산생성, 세포외부 다당류 합성정도를 평가하였다. 자일리톨 내성균주는 자일리톨 감성균주에 비해 과당을 제외한 모든 탄수화물 상에서 최종 성장이 유의하게 낮았으며(p<0.05), 산생성에는 유의한 차이가 없었다(p>0.05). 자일리톨 내성균주의 세포외부 다당류 합성은 과당을 제외한 모든 탄수화물 상에서 대체로 자일리톨 감성균주에 비해 낮았으며, 특히 엿당 상에서 뚜렷하게 낮았다. 이상의 결과들을 종합해 보았을 때, 자일리톨 감성균주와 내성균주의 독력인자 발현 정도는 탄수화물의 종류에 따라 차이를 보이기는 하나, 자일리톨 내성균주의 독력이 자일리톨 감성균주에 비해 대체로 낮으므로, 자일리톨의 장기적인 섭취에 의해 형성된 구강 내 자일리톨 내성균주는 자일리톨 감성균주에 비해 치아우식예방에 더 유리할 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제23권4호
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• pp.534-538
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• 2013

The effects of lights with different wavelengths on the growth and the yield of extracellular polysaccharides of Nostoc flagelliforme cells were investigated in a liquid cultivation. N. flagelliforme cells were cultured for 16 days in 500 ml conical flasks containing BG11 culture medium under $27{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light intensity and $25^{\circ}C$ on a rotary shaker (140 rpm). The chlorophyll a, phycocyanin, allophycocyanin, and phycoerythrin contents in N. flagelliforme cells under the lights of different wavelengths were also measured. It was found that the cell biomass and the yield of polysaccharide changed with different wavelengths of light. The biomass and the yield of extracellular polysaccharides under the red or violet light were higher than those under other light colors. Chlorophyll a, phycocyanin, and allophycocyanin are the main pigments in N. flagelliforme cells. The results showed that N. flagelliforme, like other cyanobacteria, has the ability of adjusting the contents and relative ratio of its pigments with the light quality. As a conclusion, N. flagelliforme cells favor red and violet lights and perform the complementary chromatic adaptation ability to acclimate to the changes of the light quality in the environment.

• 생명과학회지
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• 제13권6호
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• pp.871-878
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• 2003

한천, 키틴, 셀룰로오스, 자일란, 만난과 같은 복합다당류들에 대한 분해능을 나타내는 효소들을 생산하는 해양미생물을 홍조류인 Porphyra dentata로부터 분리하였다. 분리균 BK1은 그람음성, 호기성 간균으로 DNA의 G+C함량은 51.6 mol%를 나타내었다. 주요 isoprenoid quinine 구성 성분은 ubiquinone-8로 확인되었고, 주요 세포 지방산은 C16:0, C16:1 w6c, C18:1 w7c로 밝혀졌다. 16S rRNA서열의 비교분석 결과는 분리균 BK1이 Pseudomonas 속의 일원인 것으로 확인되었다. 이러한 결과를 바탕으로 분리균 BKl은 Pseudomonas sp. BKl으로 명명하였다.

• Journal of Ginseng Research
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• 제37권3호
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• pp.293-299
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• 2013

20S-dihydroprotopanaxadiol (2H-PPD) is a derivative of protopanaxadiol, a glycone of ginsenosides prepared from Panax ginseng. Although ginsenosides and acidic polysaccharides are known to be major active ingredients in ginseng, the immunopharmacological activities of their metabolites and derivatives have not been fully explored. In this study, we aimed to elucidate the regulatory action of 2H-PPD on the function of monocytes and macrophages in innate immune responses. 2H-PPD was able to boost the phagocytic uptake of fluorescein isothiocyanate-dextran in macrophages and enhance the generation of radicals (reactive oxygen species) in sodium nitroprusside-treated RAW264.7 cells. The surface levels of the costimulatory molecules such as CD80 and CD86 were also increased during 2H-PPD treatment. In addition, this compound boosted U937 cell-cell aggregation induced by CD29 and CD43 antibodies, but not by cell-extracellular matrix (fibronectin) adhesion. Similarly, the surface levels of CD29 and CD43 were increased by 2H-PPD exposure. Therefore, our results strongly suggest that 2H-PPD has the pharmacological capability to upregulate the functional role of macrophages/monocytes in innate immunity.

• 한국식물병리학회지
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• 제11권3호
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• pp.265-270
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• 1995

Transposon mutation of Xanthomonas campestris pv. vesicatoria (Xcv) was induced by using transposon omegon ($\Omega$)-Km (Tn $\Omega$Km), which was confirmed by resistance to kanamycin (KMr), and nonpathogenic mutants were selected through the inoculation test on pepper plants. The mutagenesis frequency was about 6$\times$10-8, and 53 out of 2,000 Kmr bacterial colonies tested were nonpathogenic to the pepper cultivar Cheung-Hong. Optimum conditions for the Tn $\Omega$Km mutagenesis of Xcv were Luria Bertani (LB) broth medium for culture of Xcv, yeast extract-dextrose-CaCO3 (YDC) agar medium for selection of Tn $\Omega$Km-mediated mutants, and over 1 to 2 in the ratio of the donor (Escherichia coli S17-1 with the plasmid pJFF350 $\Omega$Km) and the recipient (Xcv) in the culture for the mutagenesis. One of the 4 nonpathogenic mutants (WNP1, WNP3, WNP4 and WNP5), which had been reconfirmed through the inoculation on pepper cv. Dabokgun, showed no differences in the production of exoenzymes such as protease and polygalacturonase and extracellular polysaccharides in vitro and the bacterial growth rate from those of the wild type of Xcv.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1109-1121
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• 2009

In an attempt to discover novel biomarker proteins in type 2 diabetes prognosis, we investigated the influence of hypoglycemic extracellular polysaccharides (EPS) obtained from the macrofungus Tremella fuciformis on the differential levels of plasma proteins in ob/ob mice using two-dimensional gel electrophoresis (2-DE). The 2-DE analysis demonstrated that 92 spots from about 900 visualized spots were differentially regulated, of which 40 spots were identified as principal diabetes-associated proteins. By comparing control with EPS-fed mice, we found that at least six proteins were significantly altered in ob/ob mice, including Apo A-I, IV, C-III, E, retinol-binding protein 4, and transferrin, and their levels were interestingly normalized after EPS treatment. Western blot analysis revealed that the altered levels of the two regulatory molecules highlighted in diabetes and obesity (e.g., resistin and adiponectin) were also normalized in response to EPS. The Mouse Diabetes PCR Array profiles showed that the expression of 84 genes related to the onset, development, and progression of diabetes were significantly downregulated in liver, adipocyte, and muscle of ob/ob mice. EPS might act as a potent regulator of gene expression for a wide variety of genes in ob/ob mice, particularly in obesity, insulin resistance, and complications from diabetes mellitus.

• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.270-276
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• 1998

Extracellular ${\alpha}$-glucosidase was purified to homogeneity from moderately thermophilic Bacillus sp. DG0303. The thermostable ${\alpha}$-glucosidase was purified by ammonium sulfate fractionation, ion-exchange chromatography, preparative polyacrylamide gel electrophoresis (PAGE), and electroelution. The molecular weight of the enzyme was estimated to be 60 kDa by SDS-PAGE. The optimum temperature for the action of the enzyme was at $60^{\circ}C$. It had a half-life of 35 min at $60^{\circ}C$. The enzyme was stable at the pH range of 4.5~7.0 and had an optimum pH at 5.0. The enzyme preparation did not require any metal ion for activity. The thermostable ${\alpha}$-glucosidase hydrolyzed the ${\alpha}$-1,6-linkages in isomaltose, isomaltotriose, and panose, and had little or no activity with maltooligosaccharides and other polysaccharides. The $K_m$ (mM) for p-nitrophenyl-${\alpha}$-D-glucopyranoside (pNPG), panose, isomaltose, and isomaltotriose were 4.6, 4.7, 40.8, and 3.7 and the $V_{max}$(${\mu}mol{\cdot}min^-1$$mg^-1$) for those substrates were 5629, 1669, 3410, and 1827, respectively. The N-terminal amino acid sequence of the enzyme was MERVWWKKAV. Based on its substrate specificity and catalytic properties, the enzyme has been assigned to be an oligo-1,6-glucosidase.