• Journal of Environmental Science International
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• v.17 no.9
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• pp.1033-1037
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• 2008

The effects of inorganic salts, inoculum concentration, aeration rate and shaking speed on insoluble phosphate solubilization by Pseudomonas fluorescens RAF15 were investigated. Soluble phosphate production was dependent on the presence of $MgCl_2{\cdot}6H_2O$ and $MgSO_4{\cdot}7H_2O$ in the medium. Supplementation of medium with 0.01% $CaCl_2{\cdot}2H_2O$ and 0.01% NaCl slightly increased soluble phosphate production. The optimal medium compositions for the solubilization of insoluble phosphate by P. fluorescens RAF15 were 1.5% glucose, 0.005% urea, 0.3% $MgCl_2{\cdot}6H_2O$, 0.01% $MgSO_4{\cdot}7H_2O$, 0.01% $CaCl_2{\cdot}2H_2O$ and 0.01% NaCl, respectively. Optimal inoculum concentration was 2.0%(v/v). Maximum soluble phosphate production was obtained with 20-50 ml/250-ml flask and 200 rpm of shaking speed, respectively. The addition of EDTA decreased cell growth and soluble phosphate production.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.78-82
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• 2013

A novel Chryseobacterium sp. JK1 strain isolated from soil had been reported that this isolate produced large amount of extracellular protease at mesophilic temperature in previous study. The optimal temperature and pH of extracellular protease were $40^{\circ}C$ and 7.0, respectively, showing narrow range of optimal temperature and relatively broad activity from pH 6.0 to 9.0. In addition, the protease showed greatest activity against skim milk and lowest against bovine serum albumin (BSA). The protease strongly inhibited by ethylenediaminetetraacetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA) or phenylmethylsulfonyl fluoride (PMSF), and addition of cation $Ag^+$ or $Cu^{2+}$, and slightly inhibited by $Al^{3+}$. No significant inhibition was found with pepstatin, and addition of cation, $K^+$, $Ca^{2+}$, $Na^+$, $Fe^{2+}$ or $Mg^{2+}$. On the contrary, protease was enhanced by addition of divalent cation $Mn^{2+}$ (5 mM). Zymography analysis of concentrated culture supernatant revealed two major bands at 67 and 145 kDa. These results suggest that Chryseobacterium sp. JK1 strain produced extracellular neutral serine proteases which could apply in food industry.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.377-384
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• 2009

Among 27 Bacillus sp. isolated from Meju, a traditional Korean soybean fermented food, a strain MJ-226 was selected due to its strong fibrinolytic activity, and it was identified to be Bacillus subtilis MJ-226 according to morphological and biochemical characterization and sugar utilization. The fibrinolytic enzyme of B. subtilis MJ-226 was maximally produced by cultivating in the Tryptic Soy Broth (TSB) for 24~26 h at $37^{\circ}C$, and the enzymes activity was promoted with adding glucose, fructose, peptone or yeast extract to TSB. The fibrinolytic enzyme was stable at the range of pH from 6.0 to 8.0, and between 35 and $40^{\circ}C$. Also, when the crude enzyme was exposed to various metal ions and chemical inhibitors for 12 h, the enzyme stability was maintained by $MnSO_4$, $CaCl_2$, KCl, and NaCl. However, the stability was destroyed by treatment with $CuSO_4$, $MgSO_4$, $ZnSO_4$, $FeSO_4$, and $BaCl_2$, and the enzyme was unstable in the presence of chemical inhibitors such as iodoacetic acid, leupeptin, phenylmethanesulphonyl fluoride (PMSF), sodium dodecyl sulfate (SDS), thiourea, trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA).

• Proceedings of the Ginseng society Conference
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• 1990.06a
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• pp.132-136
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• 1990

The metabolic disturbance and nephrotoxicity induced by sodium dichromate (20 mg/kg, SC) have been diminished by the administration of Korean red ginseng extract (100 mg/kg, PO). Red ginseng has a powerful potency on the blood urea nitrogen (BUN) increment shown in the early 2h after dichromate intoxication. It normalized the dichromate induced hepatic glycogenolysis. The effect of red ginseng on dichromate induced nephrotoxicity was investigated by hematological analysis, and urinalysis. Ginseng treatment significantly reduced the increases in the urinary excretion of protein and glucose. These effects were dose dependent. Ginseng protected the accumulation of BUN and cretonne in the blood, caused by dichromate intoxication. Unlike CaEDTA, ginseng did not change the urinary excretion chromium. And it could not convert htxavalent chromium to trivalent chromium. These results suggest that ginseng treatment is effective in decreasing the metabolic disturbance, one of the earliest signs of dichromate toxicity, resulting in the protective effect of dichromate induced renal damage.

• The Korean Journal of Physiology
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• v.8 no.1
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• pp.45-53
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• 1974

The effects of kanendomycin on the potassium permeability in the rabbit erythrocyte membrane are investigated and the results are summarized as follows. 1. Kanendomycin causes the efflux of $K^+\;and\;influx\;of\;Na^+$ across the rabbit erythrocyte membrane. 2. Osmotic resistance of kanendomycin treated erythrocytes is diminished. This diminution of osmotic resistance is more pronounced by increasing concentration of kanendomycin and longer incubation time. But osmotic resistance is rather increased in the presence of lower concentration of kanendomycin. 3. Cysteine and glutathione have little influence on $K^+$ efflux induced by kanendomycin. 4. EDTA has no effect on the increase in $K^+$ outflux by kanendomycin while PCMB augments slightly on $K^+$ outflux. 5. Kanendomycin inhibits $Ca^{++}$ binding competitively to rabbit erythrocyte membrane fragments.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.123-128
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• 1991

Addition of two different salt mixtures of sodium phosphates, Ca-EDTA, $NaNO_2$ and sodium citrate were investigated for their effects on relative viscosity, textrue, sensory properties of kimchi and solids contents of kimchi and kimchi liquid during fermentation at $4{\sim}3.5^{\circ}C$. The salt mixtures were added into half fermented kimchi with the concentration range of $0.001{\sim}0.01\;M$. The results showed that higher values in viscosity of kimchi liquids were obtained for those fermented at low temperature and with salts mixtures added. The hardness of Chinese cabbage was gernerally increased until pH 4.0 reached and then decreased thereafter for those fermented without salts mixture. However the salts added kimchi showed no decrease and a slightly harder texture measured at the late stage of fermentation. Soluble solids concentration steadly decreased in kimchi liquids for those salts mixture added while those without salts mixture were initially increased followed by slow decrease. Comparison of sensory properties showed that the degree of changes was reduced when salt mixture was added. Higher scores in fresh-sourness and acidic taste, hardness and chewiness in texture and lower moldy odor were obtained when the data was compared for those kimchi having the pH range of $4.0{\sim}4.2$.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.608-608
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• 2003

The main objectives of root canal therapy are cleaning and shaping and then obturating the root canal system in 3 dimensions to prevent reinfection. Many instrumentation techniques and devices, supported by an irrigation system capable of removing pulp tissue remnants and dentin debris, have been proposed to shape root canals. But current regimens in chemomechanical debridement using instrumentation and irrigation with NaOCl are not predictably effective in root canal disinfection. These findings are not surprising because the root canal system is complex and contains numerous ramifications and anatomical irregularities. The microorganisms in root canals not only invade the anatomic irregularities of the root canal system but also are present in the dentinal tubules. Therefore further disinfection with an effective antimicrobial agent may be necessary and it well1mown that use of intracanal medication will lower bacterial count in infected root canals. Calcium hydroxide has a long history of use in endodontics, and more attention has been given to the use of calcium hydroxide as intracanal dressing for the treatment of infected pulp. However, when treatment is completed in one visit, no intracanal medications other than intracanal irrigants are used. Recently, a mixture of a tetracycline isomer, an acid, and a detergent(MTAD), has been introduced as a final rinse for disinfuction of the root canal system. It has been shown that MTAD is able to remove the smear layer with minimal erosive changes on the surface of dentin, and is effective against Enterococcus faecalis, a microorganism resistant to the action of other antimicrobial medications. In another study, the ability of MTAD was investigated to disinfect contaminated root canals with whole saliva and compared its efficacy to that of NaOCl Based on the results, it seems that MTAD is significantly more effective than 5.25% NaOCl in eradicating bacteria from infected root canals. In the cytotoxicity evaluation, MTAD is less cytotoxic than engenol, 3% $H20_2,\;Ca(OH)_2$ paste, 5.25% NaGCl, Peridex, and EDTA and more cytotoxic than 2.63%,1.31% and 0.66% NaOCl. Is it promising or transient?

• Ocean and Polar Research
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• v.39 no.4
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• pp.269-277
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• 2017

Medium compositions for the hyperthermophilic archaeon, Thermococcus onnurineus NA1 was statistically optimized to enhance formate-driven hydrogen ($H_2$) production by using response surface methodology. From the Plackett-Burman design-based experiment, it was confirmed that among the minor components of medium such as KCl, $MgSO_4$, $NH_4Cl$, Cystein-HCl, trace elements, Fe-EDTA and $CaCl_2$, the trace elements were screened as the only positively effective components with respect to $H_2$ production. Subsequently, the optimal concentrations of the trace elements and the major components of a medium such as NaCl, yeast extract and sodium formate were determined from the five-level central composite design (CCD)-based experiment. The resulting quadratic model predicted the maximum $H_2$ production of 46.6 mmol/L in serum bottle and it was validated experimentally using the optimal medium initially supplemented with 26.70 g/L of NaCl, 9.81 g/L of sodium formate, 3.50 g/L of yeast extract and 4.59 mL/L of trace elements. From the duplicate batch cultivations in the fermentor using the optimized medium, the a maximum $H_2$ production rate up to 71.8 mmol/L/h could be obtained, which was a 65% enhanced value compared with that obtained using the control medium, showing the high efficiency of the optimized medium.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.142-149
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• 1988

This experiment was carried out to obtain a hybrid with potent ethanol fermenting ability, by means of protoplast fusion between a thermophilic strain (D-71) of Saccharomyces cerevisiae and an osmotolerant strain (SR-S) of Zygosaccharomyces rouxii. The conditions for formation of protoplasts from both strains and for their fusion and regeneration were studied. Favorable conditions for formation of protoplasts from Saccharomyces cerevisiae D-71 were : treatment of the cells at late-exponential phase with 2-mercaptoethanol (l% v/v) for 10 minutes in the presence of 0.5M sorbitol, then incubation for 60 minutes in the set medium containing Zymolyase-20T (4mg/$m\ell$) ; and from Zygosaccharomyces rouxii SR-S were : treatment of the cells at mid-exponential phase with 2-mercaptoethanol (1% v/v) for 10 minutes in the presence of 0.5M or 1M mannitol, then incubation for 120 minutes in the set medium containing Zymolyase-20T(4mg/$m\ell$). The protoplasts of parental cells were fused in the presence of 20mM CaCl$_2$, 0.5M sorbitol and 40% of polyethyleneglycol (M.W 4000), then fusants obtained were selected as regenerated colonies which embedded and grown in the minimal medium containing 3% of agar. The frequencies of fusant formation were 1.2$\times$10$^{-6}$ to 9.1$\times$10$^{-6}$ for the regenerated protoplast.

• Journal of Life Science
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• v.11 no.6
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• pp.561-567
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• 2001

To isolate and purify fibrinolytic active substance from Sarcodon aspratus(N $H_4$)$_2$S $O_4$ precipitation, DE52 anion exchange column chromatography, Sephacryl-S 200gel filtration chromatography and Mono S cation FPLC were carried out and the characterizations of the purified enzyme were investigated. The bound active fraction on DE52 anion exchange column chromatography were eluted with 0.2 M NaCI and the fibrionlytic enzyme was purified after following Sephacryl-S200 gel fitration chromatography and Mono S cation EPLC. The specific activity of purified enzyme was 55.2 U/mg protein and increased 11.3 fold comparing crude extract and the yield was 49.5%. 12% SDS-PAGE electrophoresis and gel filtration chromatography revealed that Sarcodon aspratus fibrionloytic enzyme was highly purified and had 29.300 Da molecular weight. Enzyme activity of the purified fibrinolytic enzyme from Sarcodon aspratus was increased on higher pH and was stable until pH 10.5. On temperature dependent stability, the enzyme activity was decrease sharply but remained 25% relative activity on 8$0^{\circ}C$. This enzyme activity was inhibited by heavy metal ion, C $U^{2+}$ and $Co^{3+}$ with 68% and 38%, respectively. And also, the enzyme activity was inhibited with $Ca^{2+}$ chelator EDTA and serine protease inhibitor PMSF. These results from this study suggested that the fibrinolycit enzyme from Sarcodon aspratus is a serine protease and the enzyme activity was increased by $Ca^{2+}$ or $Mg^{2+}$ ion.n.ion.n.