• 한국어병학회지
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• 제26권3호
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• pp.219-229
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• 2013

본 실험은 TBT에 노출된 돌돔의 성장 및 혈액학적 변동을 검토하기 위하여 실시하였다. 돌돔은 TBT 0, 1, 2, 4, $8{\mu}g/L$ 농도에서 4주간 노출하였다. 돌돔의 성장은 $8{\mu}g/L$ TBT 농도에서 유의한 감소를 나타냈다. RBC count, hematocrit 값, hemoglobin 농도, 혈청 glucose 농도는 $8{\mu}g/L$ TBT 농도에서 유의한 감소를 나타낸 반면, 총 단백질 농도는 유의한 증가를 나타냈다. 또한 GOT 및 GPT 활성은 $8{\mu}g/L$ TBT 농도에서 유의한 증가를 나타냈다. 따라서 해역에 TBT 농도 $8{\mu}g/L$ 이상의 존재할 경우에는 돌돔의 성장 및 혈액학적 변동이 예상된다.

• Journal of Pharmaceutical Investigation
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• 제36권4호
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• pp.263-269
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• 2006

Deficiencies in the early ADMET(absorption, distribution, metabolism, elimination and toxicity) information on drug candidate extract a significant economic penalty on pharmaceutical firms. Microscale cell culture analogue-microscale gastrointestinal(${\mu}CCA-{\mu}GI$) device using Caco 2, L2 and HEp G2/C3A cells, which mimic metabolic process after absorption occurring in humans was used to investigate the toxicity of the model chemical, acetaminophen(AAP). The toxicity of acetaminophen determined after induction of CYP 1A1/2 in Caco 2 cells was not significant. In a coculture system, although no significant reduction in viability of HEp G2/C3A and L2 cells was found, approximately 5 fold increase in the CYP 1A1/2 activity was observed. These results appear to be related to organ-organ interaction. The oral administration of a drug requires addition of the absorption process through small intestine to the current ${\mu}CCA$ device. Therefore, a perfusion coculture system was employed for the evaluation of the absolution across the small intestine and resulting toxicity in the liver and lung. This system give comprehensive and physiologic information on oral uptake and resulting toxicity as in the body. The current ${\mu}CCA$ device can be used to demonstrate the toxic effect due to organ to organ interaction after oral administration,

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.291-294
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• 2000

Thraustochytrium aureum ATCC 34034를 인공 해수 배지에서 $24^{\circ}C$, 200rpm, 초기 pH 6으로 고정하여 빛을 가하면서 3일간 배양을 한 결과, 최대 건조 균체량은 1.34g/L이었으며, 최대 DHA생산량은 41.4mg/L이었다. 모든 실험에서 탄소원으로 glucose를 5g/L로 고정하였다. YM배지와 YPG배지에서는 Thraustochytrium aureum이 DHA를 생산하지 못하였으며, 이 균주가 해양 미생물이라는 점을 고려해보면, 성장과 DHA생산에 있어서 염분이 중요한 영향을 미친다고 생각된다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.363-366
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• 2001

본 연구는 Lentinus edodes의 액체배양을 통하여 물리 ${\cdot}$ 화학적인 방법을 이용, 고농도의 탄수화물 복합효소를 얻어 hemicellulose와의 반응을 거쳐 고수율의 아라비 녹실란을 얻는데 그 목적이 있다. 온도 $24^{\circ}C$, pH 5.5. working volume 100mL, 접종비 5%. 200rpm이며 가장 적합한 C-source 로서는 glucose가 선택되었으며 N - source로서는 yeast extract가 선택되었다.

• 한국물환경학회지
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• 제32권3호
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• pp.291-296
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• 2016

This study investigated the potential use of soybean stover (SS) (0.1-0.5 g/100 mL)and rice hull (RH) (1.5-3.5 g/100 mL) derived biochars for removing methylene blue (100 mg/L) from wastewater compared to activated carbon (AC) (0.1-0.5 g/100 mL). The adsorption equilibrium data were best represented by Langmuir adsorption isotherm. The calculated maximum adsorption capacity was 71.42 mg/g for AC, 30.30 mg/g for SS, and 4.76 mg/g for RH. The adsorption kinetics was found to follow the pseudo-second order kinetics model. The rate constant was 0.0020-0.0065 g/mg.min for AC, 0.0069-0.5787 g/mg.min for SS, and 0.1370-0.3060 for RH. AC and SS biochars showed considerable potential for adsorption.

• Environmental Engineering Research
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• 제11권2호
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• pp.77-83
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• 2006

The hot spring water of the north Jeonla province such as Wanggung, Jookrim, Seokjung, and Hwasim, has fluoride concentration of 3.9 mg/L, 12.7 mg/L, 1.9 mg/L, and 6.3 mg/L, respectively. These figures fairly exceed the Korean and WHO standard for potable water, which is 1.5 mg/L. Therefore, in this study, research on elimination of fluoride in a hot spring water of Jookrim region, which has the highest level of fluoride concentration level in the north Jeonla province, was carried out. In analysis of Jookrim hot spring water according to the water quality standard for potable water, pH was very high at 9.25 and the concentration of fluoride was 10 times higher than the standard at 18.2 mg/L. Other measurements were within the standard or not detected. After injecting 10g of activated carbon for elimination of fluoride, the fluoride concentration was measured at 13.5 mg/L, and when 70mL or more of alum 10 g/L solution was injected, the concentration was measured at 2.8 mg/L, and injecting 3g of lime was measured at 9 mg/L. Alum showed the best elimination performance among all individual injections. Injection of 25 mL of activated carbon and 100 mL of alum solution together reduced the fluoride concentration down to 1.3 mg/L, which is under the potable standard. Injection of lime 1g and 75 mL of alum 10 g/L solution together reduced fluoride concentration to 4.1 mg/L. From the modifying HRT, by using ion exchange resin column, the pH was stabilized when HRT was Imin and showed range of $6.7{\sim}7.8$. The fluoride concentration reduced gradually as the HRT increased, and satisfied the potable standard when HRT passed 6 min, and after 30 min HRT, the concentration of fluoride was 0.05 mg/L: almost eliminated.

• Journal of Microbiology and Biotechnology
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• 제8권6호
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• pp.601-605
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• 1998

For the resolution of L-carnitine from DL-carnitine, resting cells of Enterobacter sp. NH-104, which had a higher capacity of D-carnitine decomposition, were harvested at maximal specific activity of D-carnitine decomposition of 47.05 unit/mg cell. The cells were frozen at $-80^{\circ}C$ to assess functions as enzyme sources. Optimal concentration of cells and DL-carnitine were 17 g/$\ell \; and \; 20 g/\ell$, respectively, and reaction buffer was best at 75 mM of Tris. HCl. Optimal temperature and pH were $36^{\circ}C$ and 8.2, respectively. When the reaction at optimal conditions was carried out for 14 h, the optical purity was 98.21 %, and the quantity and yield of remaining L-carnitine were 4.432 g/$\ell$ and 44.32%, respectively.

• 한국축산시설환경학회지
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• 제19권1호
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• pp.55-62
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• 2013

Teff grass is a warm season C4 annual grass that is used for dry hay, silage and haylage. We have developed a high-frequency plant regeneration system for teff grass via callus culture using mature seeds. It was revealed that mature seeds cultured on MS medium supplemented with 2 mg/l 2,4-D, 0.5 g/L proline, 0.5 g/L casamino acid and 3 g/L Gelrite under light condition produced the highest percentage of callus formation (91.9%). Addition of cytokinins (BA) at 0.0~0.5 mg/L to media containing 2 mg/l 2,4-D enhanced callus growth. The most suitable medium for plant regeneration from dehydrated calli was MS agar medium supplemented with 0.1 mg/l NAA, 1 mg/l BA, 0.5 g/L proline, 0.5 g/L casamino acid 3 g/L Gelrite which induced the highest percentage of calli forming shoots (47.0%). The shoots were rooted at the highest rate (100%) when transferred onto 1/2 MS medium and acclimated in greenhouse conditions.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권6호
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• pp.349-353
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• 2003

The physiological characteristics of cultures of very high cell mass (e.g. 10g cell mass/L), termed“ultrahigh cell density cultures”is reviewed. A close relationship was found between the length of the optical path (OP) in flat-plate reactors and the optimal cell density of the culture as well as its areal (g m$\^$-2/ day$\^$-1/) productivity. Cell-growth inhibition (GI) unfolds as culture density surpasses a certain threshold. If it is constantly relieved, a 1.0cm OP reactor could produce ca. 50% more than reactors with longer OP, e.g. 5 or 10cm. This unique effect, discovered by Hu et al. [3], is explained in terms of the relationships between the frequency of the light-dark cycle (L-D cycle), cells undergo in their travel between the light and dark volumes in the reactor, and the turnover time of the photosynthetic center (PC). In long OP reactors (5cm and above) the L-D cycle time may be orders of magnitude longer than the PC turnover time, resulting in a light regime in which the cells are exposed along the L-D cycle, to long, wasteful dark periods. In contrast, in reactors with an OP of ca. 1.0 cm, the L-D cycle frequency approaches the PC turnover time resulting in a significant reduction of the wasteful dark exposure time, thereby inducing a surge in photosynthetic efficiency. Presently, the major difficulty in mass cultivation of ultrahigh-density culture (UHDC) concerns cell growth inhibition in the culture, the exact nature of which is awaiting detailed investigation.

• Journal of Microbiology and Biotechnology
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• 제7권5호
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• pp.318-322
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• 1997

In order to isolate a microorganism having preferential degradation of D-carnitine from DL-carnitine, a bacterium assimilating D-carnitine as a sole carbon and energy source was isolated from soil by enrichment culture and partially identified as Enterobacter sp. Also, a mutant having lessened L-carnitine decomposition rates was selected with nitrosoguanidine mutagenesis, which led to decrease the specific activities of carnitine dehydrogenase (7.6-fold) and ${\beta}$-hydroxybutyrate dehydrogenase (9.5-fold) as compared to the wild strain. Meanwhile, optimal culture conditions for optical resolution of DL-carnitine were investigated. Under optimal conditions, 3.53 g/l L-carnitine was obtained from 20 g/l DL-carnitine, which corresponded to 35.3% L-carnitine yield and 97.9% optical purity.