• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.607-613
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• 1992

A tower fermentor equipped with a modified settler was used for ethanol fermentation using highly flocculating yeast, Saccharomyces uvarum. The settler was constructed of glass column divided into two chambers by a funnel shaped divider. Gas was allowed to escape from lower chamber of the settler through a small tube. This design significantly reduced the turbulence in upper chamber of the settler and made it possible to operate at high dilution rate. Using the tower fermentor, the effects of operating conditions such as initial glucose concentration, dilution rate and cell recycle ratio were studied. The maximum ethanol productivity, 64.0 g/l' h was obtained at a dilution rate 1.1 h -1 and a cell recycle ratio 5 with the corresponding ethanol concentration of 58.8 g/l, and cell mass of 88 g/l.

• Journal of Environmental Health Sciences
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• v.23 no.1
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• pp.18-27
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• 1997

The isolation, morphological study and growth characteristics of the algae were investigated from Lake Chuam. The isolated algae were applied the Agal Growth Potential test. The method of isolation and purification of the algae were used to Agar plating(AP), nutrient enrichment(NE), dilution(DI) and micro capillary technique(MC). Total isolated algae were 21 species. They were composed of Cyanophyceae, Dinophyceae, Bacillariophyceae, Euglenophyceae and Chlorophyceae. The numbers of algal strain by isolation technique were highest in dilution(21 species), and those of the rests were showed in order of NE > MC > AP. The sizes of isolated Selenastrum and Scenedesmus were $1.8\pm 1.4 \mu m$, $3.3\pm 0.9 \mu m$ in diameter and $6.4\pm 2.3 \mu m$, $13.6\pm 1.9 \mu m$ in length respectively. The morphology of isolated algae and NIES-collection strain was very similar each other, but the size was smaller isolated algae than that of NIES-collection. The optimum culture condition of isolated Selenastrum and Scenedesmus was about 30$\circ$C(25$\circ$C-35$\circ$C) in temperature and the maximum growth was appeared between 7,000 lux and 8,000 lux in the light intensity. The comparison of $\mu$(specific growth rate) on the concentration of nutrients such as nitrate and phosphate, isolated Selenastrum was appeared maximum it at 1.0 mg $NO_3-N/l$ but NIES-collection strain was showed 95% of maximum it at same nitrate concentration. Maximum g of isolated algae and NIES-collection strain in Scenedesmus onto nitrate concentration were very similar with the result of selenastrum. The specific growth rates of isolated algae and NIES-collection strain on the gradient concentration of phosphate were showed 0.72/day and 0.70/day at 0.02 mg $PO_4-P/l$ in Selenastrum but those of Scenedesmus were appeared 0.61/day and 0.57/day at same concentration $PO_4-P$.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.438-440
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• 1997

A continuous fermentation system employing immobilized cells of Zymomonas mobilis and Saccharomyces cerevisiae was studied for the mass production of ethanol. Ethanol production by cells immobilized with Ca-alginate was better than those by cells immobilized with K-carrageenan. Maximum ethanol production employing a continuous system by cells immobilized with Ca-alginate was 77.5 $g.l^{-1}h^{-1}$ at a dilution rate of 1.85 $h^{-1}$ with 82% conversion rate for Z. mobilis while that was 40.2 $g.l^{-1}h^{-1}$ at a dilution rate of 0.92 $h^{-1}$ with 85% conversion rate for S. cerevisiae. These results suggest that Ca-alginate is a better cell immobilization matrix than K-carrageenan and that immobilized cells of Z. mobilis are more efficient than S. cerevisiae for ethanol production.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.19-26
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• 1999

Strains degrading and decolorizing acid dyes, Nylosan red E-BL 150%. were isolated from natural system, was named as ARK3. The optimal culture conditions of temperature and pH were $35^\circ{C}$, 7.0, respectively. Growth rate of cells in conditions of aerobic shaking more than standing culture conspicuously increased, and optical density of those to strain ARK3 were found as 1.38 and 0.25 after 42 hrs. Decolorization efficiency in batch culture which used as immobilization media to natural zeolite was 15% after 6 hrs, while suspension culture was 5%, also its of immobilization and suspension culture were 90% and 85% after 48 hrs, respectively. Decolorization efficiency of air-lift bioreactor was more than 90% to a dilution rate of $0.038hr^{-1}$, but that was decreased as 70%, when the dilution rate was $0.05hr^{-1}$. Even though at maximum dilution rate of this study, there was not appeared "wash out" phenomienon of biomass. Decolorization efficiency was 97.7% at a dilution rate of $0.025hr^{-1}$, when influent dye concentration was $100mg/\ell$. But if influent dye concentration increased as $150mg/\ell$, even though MLVSS increased, that of treatment water decreased as 93%. Also, when influent dye concentration increased as $200mg/\ell$ and $300mg/\ell$, decolorization efficiencies of treatment water abruptly decreased as 85% and 63%, respectively. Decolorization efficiency was more than 92% to the limit volumetric loading rate of $3.75mg/\ell\cdot{hr}$hr, without regard to variation of influent dye concentration or hydraulic retention time. if volumetric loading rate was more than $3.80mg/\ell\cdot{hr}$, at same condition, decolorization efficiency was lower decrease of retention time than increase of influent dye concentration.entration.

• KSBB Journal
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• v.11 no.1
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• pp.58-64
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• 1996

The purpose of this study is to develop a continuous process for sorbitol production using Zymomonas mobilis immobilized in K-carra-geenan. The glutaraldehyde cross-linking of toluene-treated cells immobilized in alginate or chitin showed high enzyme stability for long period. However, loss of enzyme activity was observed at 23% during 210h. In order to investigate the stability of glucose-fructose oxidoreductase of cethyltrimethylammoniumbromide (CT AB) treated cells, the long term continuous process was carried out with Z. mobilis immobilized in K-carrageenan in the continuous stirred tank reactor(CSTR) and the packed bed reactor. The continuous production of sorbitol with the immobilized CT AB permeabilized cells in packed bed reactor was more stable than in CSTR. Two stage continuous process with CT AB treated cells of Z. mobilis immobilized in K-carrageenan was carried out at various dilution rates. At the first stage, the productivity was increased up to 15 g/ $\ell$ -h as dilution rate increased and decreased over 0.32$h^{-1}$ of dilution rate. Similarly, maximum productivity obtained at the second stage was 22g/$\ell$ -h at 0.32$h^{-1}$

• KSBB Journal
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• v.9 no.2
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• pp.104-107
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• 1994

A cone-type tower fermentor packed with Sacchromyces uvarum was employed to examine the continuous ethanol fermentation process. The maximum yeast concentration in the cone-type tower fermentor was 37.5-39.5g/$\ell$, the maximum ethanol productivity at the dilution rate of $hr^{-1}$ was 16.3g/$\ell$ . hr and the average ethanol yield was 0.48g EtOH/g glucose, which was 94% of the maximum theoretical yield. It was concluded that a cone-type tower fermentor might offer better perspectives for continuous ethanol fermentation.

• KSBB Journal
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• v.6 no.3
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• pp.263-270
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• 1991

The optimal cell concentration and dilution rate for maximum ethanol productivity were obtained using dynamic simulation in cell recycled continuous bioreactor. The good control performance was observed using rule-based STR (self-tuning regulator) compared to conventional STR. Rule-base contained the scheme to implement the STR in an efficient on-off way and the scheme for the controlled variable to reach the optimal value in a short time. Since a mathematical model was used to analyze and estimate the changes of the state variables and the parameters, it was possible to understand the physical meaning of the system.

• Journal of Pharmacopuncture
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• v.4 no.2
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• pp.5-15
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• 2001

This study was carried out for production of neutral antibody to bee venom $(anti-phospholipase\;A_2IgY)$. Hen layings were injected repeatedly with bee venom and phospholipase $A_2$ with Freund's adjuvant. Specific antibody in egg yolk from immunized hen laying was separated, and purified, also immunological characteristics of anti phospholipase $A_2\;IgY$ was invested. The results were summarized as follows: 1. Phospholipase $A_2$ was showed single band at molecular weight 17,000 in SDS-PAGE and bee venom was showed two band at molecular weight 17,000 and under molecular weight 6,500 in SDS-PAGE. 2. During 70 days after hen immunized with bee venom and phospholipase $A_2$, antibodies(anti-bee venom IgY) to bee venom were showed poor ELISA value in egg yolk, but antibodies$(anti-Phospholipase\;A_2IgY)$ to phospholipase $A_2$ in egg yolk were increased ELISA value from 8 days or 15 days and found maximum ELISA value at 42 days. Also after booster at 49 days, ELISA value of anti Phospholipase $A_2\;IgY$ in egg yolk was supported at optical density(O.D) 1.0 level, continuously. 3. Titer of phospholipase $A_2\;IgY$ was showed 1: 32,000. 4. In double immunodiffusion test to phospholipase $A_2$ after double dilution of anti-phospholipase $A_2\;IgY$, only precipitation line was made in 1:1 dilution well of anti-Phospholipase $A_2\;IgY$. But In immunodiffusion test to anti-phospholipase $A_2\;IgY$ after double dilution of phospholipase $A_2$, Precipitation line to 250ul/ml well of phospholipase $A_2$ was showed. In double immunodiffusion test to bee venom(1mg/ml) after double dilution anti-phospholipase $A_2\;IgY$, all well without 1:32 dilution well were showed strong precipitation line. 5. In dot bloting test to anti-phospholipase $A_2\;IgY$ after diluting bee venom(0.5mg/ml), dot bloting color was showed clearly to $1/100(5{\mu}g/ml)$ in bee venom.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.716-721
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• 1999

It has been known that continuous cultivation of hairy root is difficult to maintain for a long period of time compared to the microbial and callus cultures. Chemostat cultivation was successfully carried out in order to economically produce a plant-based colorant, betacyanin, from red beet hairy root for more than 85 days in a 14-1 fermentor. The result from the chemostat cultivation was compared to those of the batch and fed-batch cultivations of red beet hairy roots. It was shown that hairy root reached its steady state within 50 days of the cultivation, and then maintained for about 25-30 days in a wide range of dilution rates. Total betacyanin production from the continuous process was also calculated to be 2.65g at 0.28(l/d) of dilution rate, compared to 0.196g from fed-batch cultivation. It was found that betacyanin production was a partially growth related process, yielding 0.376 mg/g-fresh wt. cell and $1.89{\times}10^{-5}$ mg/g-fresh wt. cell/d, with 0.92 of correlation factor in a partial growth-product model. It was also shown that the cell growth required was relatively large for maintenance amount of energy at a low dilution rate. The growth of hairy root was inhibited by high light intensity in following a photo-inhibition model. The growth parameters were estimated to be 0.3(l/d), $10.56kcal/\textrm{m}^2/h$,{\;}and{\;}35.81kcal/\textrm{m}^2/h$ for the maximum specific growth rate, half saturation light intensity, and inhibition light intensity, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.5
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• pp.615-624
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• 2013

In this study, the emission patterns of reduced sulfur compounds (RSC) were investigated using four different types of food samples (boiled egg, milk, canned meat and strawberry) between fresh and decaying stages. To this end, the concentrations of RSCs were measured at storage days of 0, 1, 3, 6, and 9 under room temperature. Four sulfur compounds ($H_2S$, $CH_3SH$, DMS and DMDS) were selected as target compounds along with two reference compounds ($CS_2$ and $SO_2$). Their concentrations were quantified using GC-PFPD equipped with thermal desorption (TD) system. The boiled egg showed the highest concentration of $H_2S$ (3,655 ppb) at D-1, while $CH_3SH$ reached its maximum value of 64.4~78.5 ppb after 3 days. In milk samples, concentration of $CH_3SH$, DMS, and DMDS went up to 487, 16.3, and 578 ppb, respectively with the progress of decay (D-9). In case of canned meat, concentration of $H_2S$ and $CH_3SH$ peaked in the beginning (D-0) such as 345 and 66.6 ppb. In case of strawberry, $CH_3SH$ and DMDS showed the maximum concentrations 135 and 50.5 ppb at D-1, respectively. The olfactometry dilution-to-threshold (D/T) ratio by air dilution sensory (ADS) test showed similar patterns when sum of odor intensity (SOI) was derived via conversion of odorant concentration data. The results of this study confirm that the time of strong RSC emissions is distinguished for each food type between fresh (e.g., strawberries) and decaying conditions (e.g., milk).