• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.223-229
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• 2002

For the research of the natural marine antioxidant, several bacteria were isolated from the coast of jin-Hae in Korea. Among the marine bacteria studied, strain HJ-14, a gram-negative, motile, strait rod, aerobic, and $Na^{+}$ required bacterium showed high activity of 1,1-diphenyl-2-picrylhydrazyl radical scav- enging. The morphological, physiological, and biochemical characteristics of the strain HJ-14 were similar to those of the Alteromonas macleodii ATCC $27126^{T}$ . Thus, it was tentatively identified as Alteromonas sp. HJ-14. The compositions of major fatty acids in cell membrane of Alteromonas sp. HJ-14 were $C_{ 14:0}$ , $ C_{15:0}$ , $C_{16:0}$ and $C_{17:1}$ $_{w8c}$ , which also suggest that it is affiliated with Alteromonas sp. The optimum culture conditions for production of antioxidant materials with Alteromonas sp. HJ-14 were at $25$~$37^{\circ}C$ and pH 6~8. The optimum conditions for the production of antioxidant for carbon, inorganic nitrogen, and sodium chloride sources were 2.5%(w/v) dextrin, 0.5%(w/v) ammonium sulfate, and 2~6%(w/v) sodium chloride, respectively. The hydroxyl radical scavenging ability of Alteromonas sp. HJ-14 broth was 90.03%, which is higher than ascor-bic acid(83.28%) and lower than butylated hydroxyanisole(95.46%) and $\alpha$-tocopherol(97.17%).

• Microbiology and Biotechnology Letters
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• v.30 no.2
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• pp.142-150
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• 2002

Streptomyces polychromogenes IFO 13072 was used as a strain producing cholesterol oxidase(EC 1.1.3.6). The conditions of cholesterol oxidase production were investigated. The optimum composition of medium for production of the enzyme was 1% dextrin, 0.5% casamino acid, 0.1% $KH_2$PO$_4$, 0.5% $NaNO_3$ and 0.05% $MgSO_4$(pH 7.3). The enzyme was purified specifically by cholesterol affinity column chromatography with a yield of 23.2%. The purified enzyme showed a single polypeptide on SDS-PAGE and the molecular weight was estimated about 52,000 daltons. The optimum pH and temperature of the cholesterol oxidase were pH 7.0 and $37^{\circ}C$, respectively. The enzyme was stable in the range of pH 6.0~7.0 and $25^{\circ}C$. The cholesterol oxidase activity was strongly inhibited by metal ions such as $Hg^{2＋}$ and $Fe^{2＋}$ and inhibitors such as dithiothreitol, mercaptoethanol and isonicotinic acid. The Michaelis constant(Km) for the cholesterol was found to be 25 mM by Lineweaver-Burk plot analysis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.1148-1156
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• 2009

In order to manufacture noodles using rice flour as its main ingredient, organic acid and thickening agents have been used, and protein, dextrin, and refined salt have added. The rice flour dough that had been baked using organic acids and thickening agent showed the max weight of $2040.00\;g/cm^2$, elasticity value of 139.12%, cohesiveness of 66.05%, chewiness of 1,396.13g, and brittleness of 190,456.12g respectively. The appropriate conditions for manufacturing rice noodle using rice flour were that the rice was to be soaked for 12 hours at temperature of $20{\sim}25^{\circ}C$ and to be milled twice at temperature lower than $35^{\circ}C$. Additionally, the most ideal condition to manufacture noodles was to use the rice flour by combining protein, dextrin and refined salt using 3.88% organic acid blend and 2.82% blend of thickening agents in order to change the rice flour properties

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.235-243
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• 2006

The study was performed to identification of producing microbe Non-Cariogenicity Sugar (NCS; Fuc($1{\to}4$) gaINAc($2{\to}6$)NeuAc) with anti-caries activity, and to optimization of production condition. A typical strain which produced the NCS was identified alkalophilic Bacillus sp. S-1013 through the results of morphological, biochemical and chemotaxonomic characteristics and 16S rDNA sequencing. The optimal medium composition for the maximal production of the NCS from alkalophilic Bacillus sp. S-1013 was as follow: soluble starch 30 g, dextrin 15 g, yeast extract 5 g, peptone 10 g, $K_{2}HPO_4$ 2 g in a liter of distilled water. Optimal temperature and pH were 25 and 11.0, respectively. The highest production of NCS was shown 60 hrs cultivation using the optimal medium, and then NCS productivity and dry cell weight of culture broth increased 4.24 and 2.67 time than initial medium, respectively.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.175-182
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• 1987

A raw starch saccharifying enzyme from Aspergillus sp. SN-871 was purified by ammonium sulfate precipitation, DEAE-cellulose column chromatography, CM-Sephadex C-50 column chromatography and Sephadex G-75 gel filtration. The specific activity of purified enzyme was 18 fold and the yeild was 13.40%. The molecular weight of the purified enzyme was estimated as approximately 40,000 dalton by the method of Andrews gel filtration. The optimum pH and temperature for this enzyme were found to be 4 and $40^{\circ}C$, respectively and the stable range of pH was 2 to 5. The enzyme was themostable at below $60^{\circ}C$ and inactivated at $70^{\circ}C$. It showed a tendency to increase the enzyme activity under the presence of 0.01 M $BaCl_2$, but under 0.01 M$Pb(NO_3)_2$, $AgSO_4$, and $K_3Fe(CN)_6$ and citric acid etc. inhibited it completely. The substrate specifity of enzyme showed a tendency to increase the enzyme activity under addition of dextrin and glycogen, but under saccharose inhibited it. COD removal rate of Aspergillus sp. SN-871 was approximately 67 to 68%.

• Journal of Life Science
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• v.7 no.1
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• pp.30-38
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• 1997

For screening thermostable $\alpha$-amylase from thermophiles, various samples from extreme environments such as hot spring and sewage near them, and compoat, wereexamined microbial growth in enrichment culture medium at 55$\circ$C on the assumption that enzymes from thermophiles are inevitable thermostable. One strain showing higher $\alpha$-amylase activity was pure cultured and designated as Bacillus sp. TR-25 from the results of morphological, cultural and physiological characteristics. The most important carbon sourses for the enzyme production were soluble starch, dextrin, potato starch and corn starch. Glucose and fructose had a catabolite repression on the enzyme production. The good nitrogen sources for the enzyme production were yeat extract, nutrient broth, tryptone, corn steep liquor and ammonium sulfate. The enzyme production was accelerated by addition of CaCl$_{2}$. $\cdot $ H$_{2}$O. The optimal medium composition for the enzyme production was soluble starch 2.0%, yeast extract 0.55, CaCl$_{2}$ $\cdot $ 2H$_{2}$O 0.015, Tween 80 0.001%, pH8.0, respectively. In jar fermenter culture, this strain shows a rapid growth and required cheaper carbon and nitrogen source. These properties are very useful to fermentation industry. The $\alpha$-amylase of this strain demonstrated a maximum activity at 80$\circ$C, pH 5.0, respectively. And calcium ion did not improve thermostability of the enzyme. At 10$0^{\circ}C$, this enzyme has 235 of relative activity. Transformation was carried out by thermophilic Bacillus sp. TR-25 genomic DNA. As a result, the transformant has increased thermostable $\alpha$-amylase activity.

• The Korean Journal of Mycology
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• v.33 no.1
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• pp.22-29
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• 2005

The main objectives of this research were to study the cultural and nutritional characteristics of Tricholoma matsutake and to establish its liquid culture system. The optimum growth of T. matsutake was observed in HA and TMM agar media. Similarly highest growth was observed in PDB and TMM liquid media. The optimal temperature for the mycelial growth was $25^{\circ}C$. The most suitable carbon source was dextrin among 12 different carbon sources tested. Yeast extract and peptone were best nitrogen sources among 17 different sources tested. The optimum mineral salts were $Fe_{2}(SO_{4})_{3}{\cdot}H_{2}O$ and KCl among 9 different sources tested. Shaking culture gave higher mycelial growth compared to stationary culture. Similarly, optimum medium amount for shaking culture was 100 ml per 250 ml flask. The highest mycelial growth was obtained when $5{\sim}7$ mycelial discs were inoculated in 100 ml of medium and incubated for $8{\sim}9$ weeks, respectively. The highest proportion of mycelial growth was observed at 40 : 1 ratio of medium to inoculum volume in 8 l air-lift fermenter.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.324-331
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• 2009

MK1 strain, an obligate aerobic heterotrophic bacterium isolated from the rotten tissue of Neungee mushroom (Sarcodon aspratus), produces a copious amount of exopolysaccharide (EPS), which could evoke macrophage activation. Investigations on optimal culture conditions of MK1 and physical properties of MK1 EPS were made. Glucose, galactose, fructose, and sucrose supported well growth of MK1, but potato starch and dextrin did not. However, lactose seemed to be a less favorable carbon source. Optimal growth of MK1 was obtained at pH 7.0, $30^{\circ}C$, and 200 rpm with 2% glucose, and 0.2~0.05% $(NH_4)_2SO_4$. $EPS_{opt}$ obtained from an optimal growth condition constituted of carbon (37.1%), nitrogen (2.2%), oxygen (49.3%), and hydrogen (6.4%), but no sulfur. Paper chrogromatogram of the acid-hydrolysate of $EPS_{opt}$ suggested that MK1 EPS seemed to be hetropolysaccharide composed of a few number of monosaccharides including amino- and acidic-sugars. Its molecular mass determined by SDS-polyacrylamide gel electrophoresis varied from 14.8 to 47.9 kDa. Physical properties of $EPS_{glu}$ obtained from cell grown in glucose medium, such as relative viscosity ($_{rel}$) and crystalline morphology were rather affected by pH of the growth medium. Relative viscosity ($_{rel}$) of exopolysaccaride (0.1 g/ml) harvested from cells grown at medium pH ranging from 6.0 and 7.5 was 1.23 and 1.39, respectively. The freeze-dried exopolysaccharide obtained at low pH (6.0 and 6.5) was fine crystaloid and water-soluble, whereas those obtained at high pH (7.0 and 7.5) was rather gluey and less water-soluble.

• Journal of Life Science
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• v.34 no.9
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• pp.632-638
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• 2024

The antimicrobial activity of Bacillus amyloliquefaciens JFP-02 against nine fish pathogenic bacteria isolated from olive flounder aquaculture farms on Jeju Island was assessed under various medium compositions, pH levels, and incubation temperatures. The fish pathogenic bacteria isolated were Flexibacter maritimus, Staphylococcus caprae, Edwardsiella tarda, Streptococcus parauberis, Photo-bacterium damselae, Vibrio harveyi, Vibrio campbellii, Vibrio alginolyticus, and Vibrio anguillarum. The antibiotic susceptibility testing results for the fish pathogenic bacteria indicated the highest sensitivity to florfenicol, followed by gentamycin and neomycin. The bacteria exhibited the greatest resistance to penicillin, with amoxicillin and erythromycin showing the next highest levels of resistance. B. amyloliquefaciens JFP-02 exhibited the highest growth activity at pH 9, while the greatest antimicrobial activity was observed at pH 6. Likewise, although the highest growth occurred at 30℃, the most significant antimicrobial effect was observed at 20℃. Among the various medium components, the antimicrobial activity of B. amyloliquefaciens JFP-02 was highest when dextrin was used as the carbon source, leading to the greatest growth and antimicrobial activity. Additionally, among the nitrogen sources, the addition of yeast extract resulted in the highest growth and antimicrobial activity. For inorganic salts, although the highest growth activity was observed with MgSO₄·7H₂O and FeSO₄·7H₂O, the greatest antimicrobial effect was observed with KH₂PO₄.

• Archives of Pharmacal Research
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• v.23 no.1
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• pp.66-71
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• 2000

Peonjahwan, an oriental traditional medicine composed of crude herbal drugs and animal tissues is bitter and poorly water-soluble. To mask the bitterness of peonjahwan and enhance the release of bilirubin, one of the crude active ingredients of peonjahwan, peonja dry elixir (PDE), was prepared using a spray-dryer after extracting the crude materials in ethanol-water solution. coated peonja dry elixir (CPDE) was then prepared by coating the PDE with Eudragit acrylic resin. Panel assessed bitterness and release test of bilirubin from PDE and CPDE were carried out and compared with peonjahwan alone. PDE was found to have little effect upon the reduction of the bitterness of peonjahwan. However, the bitterness of CPDE was found to reduce to 1/4 of that of peonjahwan due to the encapsulation of crude active ingredients by the dextrin and Eudragit shell (P<0.05). The release rate of bilirubin from PDE and CPDE for 60 min increased about 3.5- and 2.5-fold, respectively, compared to peonjahwan at pH 1.2. It is concluded that CPDE, which masked the bitterness of peonjahwan and enhanced the release of bilirubin, is a preferable delivery system for peonjahwan.