• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.41-46
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• 2011

A galactose-fermenting yeasts, Saccharomyces cerevisiae No. 9, was selected by screening their abilities to produce carbon dioxide gas when grown on galactose. The selected strain, No. 9 and the reference strains NRRL Y-1528 which was exceptionally resistant to high concentration of substrate, were acclimated on sugars such as glucose, mannose, and galactose, and then their ethanol productivities were investigated during fermentation on these three carbon sources. Ethanol productivity of the strain No. 9 reached to the maximum levels after 18 h of fermentation and the ethanol yield was from 36 to 38% when presented as $[EtOH]_{max}/[Sugar]_{ini}(g/g)$, regardless of the conditions of acclimation. From the results obtained by acclimation and fermentation, it was concluded that the ethanol yields from galactose were not affected by the sugars acclimated. Improvements of the strain S. cerevisiae No. 9 were attempted to increase the fermentation efficiency and/or ethanol yields on high concentration of substrate by the conventional mutation methods employing methanesulfonic acid, ethyl ester (EMS). Mutants, Mut-5 (SJ1-40), -17 (LK4-25) and -24 (LK2-48) fermented galactose at the concentration of 20% in the levels of higher 39.9~51.6% than the mother strain, No. 9, however, their ethanol yields never exceeded those of the reference strain.

• Journal of Aquaculture
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• v.21 no.2
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• pp.63-69
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• 2008

We isolated complementary DNA(cDNA) encoding prolactin receptor(PRLR) from gill of black porgy Acanthopagrus schlegeli. Its PRLR cDNA consists of 1,611 base pairs and encodes the protein of 536 amino acids. To investigate the osmoregulatory abilities of black porgy in different salinities(35, 10 and 0 psu), we examined the expression of PRLR mRNA in osmoregulatory organs(gill, kidney and intestine) using reverse transcription(RT)-PCR. In gill and intestine, PRLR mRNA levels were high in 10 psu, and then decreased in 0 psu, but there is no changes in kidney. Also, plasma osmolality, $Na^+\;and\;Cl^-$ levels decreased during the experimental period. These results suggest that PRLR plays an important role in hormonal regulation in osmoregulatory organs during freshwater acclimation, thereby improving the hyper-osmoregulatory ability of black porgy in hypoosmotic environments.

• Journal of Environmental Health Sciences
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• v.21 no.4
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• pp.1-9
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• 1995

This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.

• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.134-139
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• 2014

The aim of this study was to establish the condition of regeneration for white balloon flower (Platycodon grandiflorum DC. cv. Jangback) and to manage for the raising of seedling with in vitro regenerated plants. It was examined that 0.5 mg/L of NAA and 1.0 mg/L of BA was the best composition for the callus and shoot induction (up to 600%). NAA was better than IBA for the induction of root and it took 16.9 days for the induction of rooting on the MS soild media containing 0.5 mg/L of NAA and the final rooting ratio was up to 75%. Out of 5 different bed soils purchased from local market, "Tosil" was identified to be the best for the acclimation and growth of in vitro regenerated balloon flower. In detail, on 8 weeks after planting of in vitro regenerated plants in pots containing "Tosil" bed soils, the plant hight was increased up to 2-fold (12.8 cm), 3.5-fold (27) for the number of leaf and 1.5-fold (4.5 cm) for the leaf length when compared to the other four bed soils, respectively. Our preliminary results indicate that it is possible to prevent the occurrence of blue balloon flower in the massive cultivated area of white balloon flower by providing the seedlings raised from in vitro regenerated plants.

• Journal of Aquaculture
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• v.20 no.4
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• pp.226-231
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• 2007

We investigated survival and osmolarity, oxygen consumption, amonia extetion and filtration rates associated with physiological responses of the tunicate Halocynthia roretzi salinity changes. Acclimation times for osmolatity in different salinities took $20{\sim}26$ hours in 60% SW (19.8 psu) and $20{\sim}25$ hours in 80% SW (26.4 psu), while their times took $7{\sim}8$ hours in 110% SW (36.3 psu). Accordingly, acclimation times for high salinities were faster than those for low salinities. Survival (%) was more than 80% at salinity over 26.4 psu, and 6 $days-LS_{50}$ was 25.4 psu. physiological responses such as oxygen consumption, amonia excretion and filtration rates of H. roretzi showed more clear reactions in the longer exposure period (four days after exposure) than that in the beginning of the exposure. To sum up the results, the tunicate might be stressed from the beginning of the exposure in low salinity.

• BMB Reports
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• v.37 no.5
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• pp.538-545
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• 2004

A new CRT binding factor (CBF) gene designated Cbcbf25 was cloned from Capsella bursa-pastoris, a wild grass, by the rapid amplification of cDNA ends (RACE). The full-length cDNA of Cbcbf25 was 898 bp with a 669 bp open reading frame (ORF) encoding a putative DRE/CRT (LTRE)-binding protein of 223 amino acids. The predicted CbCBF25 protein contained a potential nuclear localization signal (NLS) in its N-terminal region followed by an AP2 DNA-binding motif and a possible acidic activation domain in the C-terminal region. Bioinformatic analysis revealed that Cbcbf25 has a high level of similarity with other CBF genes like cbf1, cbf2, and cbf3 from Arabidopsis thaliana, and Bncbf5, Bncbf7, Bncbf16, and Bncbf17 from Brassica napus. A cold acclimation assay showed that Cbcbf25 was expressed immediately after cold triggering, but this expression was transient, suggesting that it concerns cold acclimation. Our study implies that Cbcbf25 is an analogue of other CBF genes and may participate in cold-response, by for example, controlling the expression of cold-regulated genes or increasing the freezing tolerance of plants.

• Development and Reproduction
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• v.13 no.4
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• pp.313-320
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• 2009

The aim of this study was to test if 3,5,3'-triiodothyronine (T3) are involved in the osmoregulatory actions in euryhaline starry flounder Platichthys stellatus. We investigated osmoregulatory parameters ($Na^+,\;Cl^-$ and osmolality), blood cortisol and glucose in starry flounder acclimated to seawater (SW, 33 psu) and that were transferred and allowed to acclimate to freshwater (FW, 0 psu). Fish in SW were injected with T3 (5, 10, and $15{\mu}g$/g body weight) or vehicle (0.9% NaCl), and then transferred to FW. They were sampled 3 days after the transfer. With T3 at $10{\mu}g$/g, levels of plasma $Na^+$ and $Cl^-$ were significantly higher than in sham (only saline) and control fish (without hormone and saline). Osmolality was significantly higher after injection with T3 at 10 and $15{\mu}g$/g than in the control. However, T3 at $5{\mu}g$/g had no effect on hyper-osmoregulation. In this study, all dose of T3 induced a significant increases in plasma cortisol without glucose. These results suggest a positive hyper-osmoregulatory role of T3 in starry flounder to hypoosmotic environment, maybe a positive interaction of T3 with cortisol for maintenance of hyper-osmoregulatory ability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.279-286
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• 1996

Cultivated tilapia (Oreochromis niloticus) in the fresh water were acclimated to the sea water to improve palatability of the fish meat. Physicochemical properties in the rigor mortis of those fish meats were investigated during storage at $0^{\circ}C,\;10^{\circ}C\;and\;20^{\circ}C$. The faster onset of rigor mortis was occurred in acclimated meat than fresh water cultivated meat. Both meats stored at $0^{\circ}C$ showed faster figro mortis than at $10^{\circ}C\;and\;20^{\circ}C$. Significant difference was not observed between the breaking strength and the rigor index. The breaking strength reached maximum over 12hrs after death and then gradually declined, and the rigor index was slowly increased and reached maximum over 18hrs after postmortem. Low temperature and acclimation to the sea water affected the degradation of adenosine triphosphate (ATP), accumulation of inosine monophosphate (IMP) or lactate. These results suggest that the palatability of tilapia muscle cultivated in the fresh water could be improved by acclimation to the sea water which induces the prerigor at the early state of postmortem and the physical changes of fish muscle.

• Journal of Photoscience
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• v.9 no.2
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• pp.436-438
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• 2002

Since solar radiation contains wavelength essential for photosynthesis accompanying with near-UV light, UV-B effects on biological parameters and acclimation mechanisms are influenced by photosynthetically active radiation (PAR). Therefore, to elucidate near-UV shielding mechanism in higher plants, we cultivated cauliflower under usual solar radiation and increased UV-B from fluorescent lamps, two- or three-fold excess over continuously estimated UV-B dose in PAR during daytime, using computer regulated systems. Increased UV-B radiation had little effect on growth expressed as fresh weigh and leaf area. Water soluble low molecular weight compounds showing absorption in near UV region were enhanced according to the irradiated UV-B dose. One of compounds in cauliflower leaves was identified as chlorogenic acid. This was found to have no near-UV photosenSitizerable activity and is known to have an ability to scavenge a wide species of active oxygen. Another pro-oxidant compound that generates superoxide anion radical under near-UV irradiation was not induced by increased UV-B during cultivation, and identified as lumazine, a degradation product from folic acid.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.410-414
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• 2000

The effect of the COD/N ratio on denitrification characteristics was evaluated for the development of a denitrification process. Activated sludge, acclimated to an anoxic condition, was used as the denitrifier consortium (mixture of denitrifying organisms) for enhanced nitrogen removal in a recirculating aquarium system. Synthetic wastewater containing nitrate was used as the influent solution and glucose was used as the carbon source for denitrification. The COD/N ratio varied within a range of 1.5-7.2. The denitrification efficiency was higher than 97% even at a COD/N ratio of 1.5. Under a theoretical COD/N ratio of 3.0, nitrite was detected, however, the amount was less than 1% of the total influent nitrogen. The number of both nitrate-reducing bacteria and denitrifying bacteria reached $3.5{\times}10^5/ml$ with a COD/N ratio of 1.5 after 45 days of operation.