• Ocean and Polar Research
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• v.26 no.3
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• pp.433-438
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• 2004

Stress response to the seawater acclimation in coho salmon (Oncorhynchus kisutch) smolt was investigated. Salt concentration of rearing water was gradually increased for 3 days from freshwater to seawater (30 ppt salt level). The changes of serum concentrations of cortisol as a primary stress indicator, and as secondary indicators, glucose (GLC), lactate (LAC), triglyce.ide (TG), cholesterol (CHOL), sodium ion $(Na^+)$, chloride ion $(Cl^-)$ and enzyme activities (alanine aminotransferase, ALT: aspartate aminotrasferase, AST; lactate dehydrogenase, LDH) were quantified during the acclimation experiment. Among them, cortisol, LAC, TG, CHOL, ALT, AST concentrations showed rapid increase at the first exposure to the 10ppt salt level (day 1), and began to decrease to the constant values after day 2 of adaptation at 20ppt salt level. However, LDH concentration tended to decrease during the whole experimental period. $Na^+\;and\;Cl^-$ showed slight decrease at day 1, and increased to a little bit higher values after day 2 rather than those in freshwater. All the fishes started on taking a food after day 4 of seawater adaptation. From these results, to reduce osmotic shock inducible stress to fish in seawater acclimation, gradual increase of salt levels is recommended.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.369-378
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• 2011

The effect of a homolactic inoculant containing a blend of Lactobacillus plantarum, Pediococcus acidilactici and Enterococcus faecium or, the anionic surfactant, sodium dodecyl sulphate (SDS), alone or in combination on fermentation characteristics, aerobic stability and in situ DM, OM and NDF degradability of barley silage was investigated. Barley (Hordeum vulgare, L.) was harvested (45% DM), chopped and treated with water at 24 ml/kg forage (Control), inoculant at $1.09{\times}10^5$ cfu/g forage (I), SDS at 0.125% (wt/wt) of forage (S) or with the inoculant ($1.09{\times}10^5$ cfu/g) plus SDS (0.125% wt/wt; I+S). The treated forages were ensiled in triplicate mini silos and opened for chemical and microbiological analyses on d 1, 2, 3, 7, 14, 42 and 77. Silage samples from d 77 were opened and aerobically exposed for 7 d. The in situ rumen degradability characteristics of silage DM, OM and NDF were also determined. The terminal concentration of NDF in S and I+S was lower (p<0.001) than in other treatments. Lactate concentration was higher (p<0.001) and the rate and extent of pH decline were greater (p<0.001) in I and I+S than S and Control silages. A homolactic pathway of fermentation in I and I+S was evidenced by reduced (p<0.001) water-soluble carbohydrates concentration, higher lactate (p<0.01), lower acetate (p<0.01) and lower pH values (p<0.001) than in S and Control silages. All silages remained stable over 7 d of exposure to air as indicated by lower temperatures and moulds, and by non-detectable yeast populations. The treated silages had lower DM and OM degradability than in the Control but NDF degradation characteristics of I+S were improved compared to other treatments. It is concluded that the inoculant alone improved the fermentation characteristics whereas the combination of the inoculant with SDS improved both fermentation and NDF degradability of barley silage.

• KSBB Journal
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• v.20 no.6
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• pp.425-430
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• 2005

Thermophilic $H_2$ was produced for 1 year using a bench-scale continuous stirred tank reactor(CSTR). The CSTR was inoculated with anaerobically digested sludge after heat treatment and fed with a glucose-based medium. The reactor showed relatively short start-up period(30 days) and high maximal $H_2$ yield(2.4 mol $H_2/mol$ glucose). Keeping pH 5.0 or less suppressed methanogenic activity. Bacteria affiliated with Thermoanaerobacterium thermosaccharolyticum kept being dominant from approximately 40 days as determined by DGGE. Environmental perturbation(pH or temperature) caused the decrease of biomass concentration in the reactor and the instability of reactor performance, $H_2$ production rate and $H_2$ yield. The unstable performance was accompanied with high concentration of lactate in the effluent. Taken together, the poor recovery of CSTR after perturbations could be partly explained by low biomass concentration and/or metabolic shift of the major population in the CSTR.

• Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.109-114
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• 2004

To evaluate the impact of parathion on aquatic organisms, a freshwater bagrid catfish (Pseudobagrus fulvidraco) was exposed to sublethal concentrations $(63,\;95,\;190\;and\;380\;{\mu}g/L)$ of parathion, organophosphorus pesticide for 30 days. Glucose level in the serum of the bagrid catfish was significantly increased than that of control groups in the $190\;{\mu}g/L$ concentration at 30 days and in the $380\;{\mu}g/L$ concentration after 10 days. Bilirubin level was significantly increased in the $190\;{\mu}g/L$ concentration at the end of the experiment. After 10 days, a significant differences of lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) activity increased in the ${\geq}190\;{\mu}g/L$ and $380\;{\mu}g/L$ groups. Though cholesterol concentration was stable, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in serum were significantly reduced in the $190\;{\mu}g/L$ at 10 days and in the $380\;{\mu}g/L$ concentration at the end of the experiment. In conclusion, if P. fulvidraco was chronically exposed to ${\geq}190\;{\mu}g/L$ concentration of parathion, the hematological changes may be induced due to the stress response.

• Journal of Soil and Groundwater Environment
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• v.11 no.2
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• pp.68-76
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• 2006

Anaerobic reductive dechlorination of tetrachloroethylene (PCE) to ethylene was investigated by performing laboratory experiments using semi-continuous flow two-in-series soil columns. The columns were packed with soils obtained from TCE-contaminated site in Korea. Site ground water containing lactate (as electron donor and/or carbon source) and PCE was pumped into the soil columns. During the first operation with a period of 50 days, injected mass ratio of lactate and PCE was 620:1 and incomplete reductive dechlorination of PCE to cis-DCE was observed in the columns. However, complete dechlorination of PCE to ethylene was observed when the mass ratio increased to 5,050:1 in the second operation, suggesting that the electron donor might be limited during the first operation period. Dechlorination rate of PCE to cis-DCE was $0.62{\sim}1.94\;{\mu}mol$ PCE/L pore volume/d and $2.76\;{\mu}mol$ cis-DCE/ L pore volume/d for that for cis-DCE to ethylene, resulting that net dechlorination rate in the system was 1.43 umol PCE/L pore volume/d. During the degradation of cis-DCE to ethylene, the concentration of hydrogen in column groundwater was $22{\sim}29\;mM$ and $10{\sim}64\;mM$ for the degradation of PCE to cis-DCE. These positive results indicate that the TCE-contaminated groundwater investigated in this study could be remediated through in-situ biological anaerobic reductive dechlorination processes.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1425-1429
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• 2005

Megaspahera elsdenii YJ-4, which was previously isolated as a producer of trans-10, cis-12 CLA, was studied for its carbon source on the CLA production. M. elsdenii YJ-4, was incubated with glucose and lactose, and cultured in batch and continuous culture systems with linoleic acid at various pHs to investigate CLA production. Batch cultures of the ruminal bacterium, M. elsdenii YJ-4, were resistant to stearic acid and linoleic acid, and little growth inhibition was observed even when the fatty acid concentration in the culture was as much as 4 mg $ml^{-1}$. Stationary phase batch cultures (0.25 mg bacterial protein $ml^{-1}$) that had been grown on lactate and incubated with linoleic acid (0.20 mg $ml^{-1}$) produced approximately 12 ${\mu}g$ trans-10, cis-12 CLA mg $protein^{-1}$ and little cis-9, trans-11 CLA was detected. Some linoleic acid was converted to hydrogenated products (chiefly stearic acid), but these fatty acids were less than 5 ${\mu}g$ mg bacterial $protein^{-1}$. Stationary phase batch cultures that had been grown on glucose produced at least 3-fold less trans-10, cis-12 CLA than ones grown on lactate. Cells from lactate-limited continuous cultures produced less trans-10, cis-12 CLA than those from batch culture, but only if the pH was greater than 6.4. When the pH of the lactate-limited continuous cultures was lower than 6.4, trans-10, cis-12 CLA and hydrogenated products declined. Cells from glucose-limited continuous cultures produced less trans-10, cis-12 CLA and hydrogenated products than the cells that had been limited by lactate, but pH had little impact on this production. These results support the idea that M. elsdenii YJ-4 could be one of the major producers of trans-10, cis-12 CLA which causes cows to produce milk with a low fat content.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.602-602
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• 2007

• Journal of Korean Medicine Rehabilitation
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• v.20 no.4
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• pp.17-31
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• 2010

Objectives : Ganoderma Lucidum has been used in traditional oriental medicine to treat various conditions including chronic fatigue and cough. This experimental study was designed to investigate the effects of yeast-fermented Ganoderma Lucidum extract on the fatigue of rats elicited by forced swimming. Materials and methods : The rat subjects were divided into 4 groups: normal group, control group administered with 0.9% normal saline, experimental I(Exp I) group administered with yeast-fermented Ganoderma lucidum extract and experimental II(Exp II) group administered with Ganoderma lucidum extract for 4 weeks. All the serum samples collected by heart puncture were used to measure biochemical factors such as glucose, lactate, lactate dehydrogenase(LDH), creatine kinase(CK), inorganic phosphorus, ammonia, total cholesterol(TC), triglycerides(TG), high-density lipoprotein(HDL), low-density lipoprotein(LDL), aspartate transaminase(AST), alanine transaminase(ALT). Results : 1. Weight change and swimming time were not significantly different in the experimental groups as compared with control group. 2. Lactate was significantly decreased in the experimental groups as compared with control group. Inorganic phosphorus was also significantly decreased in the Exp I group as compared with control group(p<0.05). 3. Serum lipid concentration was not significantly different in the experimental groups as compared with control group. 4. AST and ALT were significantly decrease in the experimental groups as compared with control group. Conclusions : Yeast-fermented Ganoderma lucidum in forced swimming rats would appear to reduce fatigue-related factors, AST, ALT of serum and promote anti-fatigue effect.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.270-277
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• 2003

In order to enhance the firmness and shelf-life of kimchi, as well as to increase the content of well-absorbed digestible calcium, the effect of calcium lactate (CaL) treatment of salted Chinese cabbage on pH, tit ratable acidity, total microbes, lactic acid bacteria, alcohol insoluble substance (AIS) content, firmness, mineral content and tissue structure were investigated. Treatment with the Cal solution increased pH and decreased titratable acidity, which was more pronounced at higher concentrations. The edible period evaluated by pH was 7～8 days for non-treated kimchi, 10 days for 1 % treated kimchi, 15 days for 2% treated kimchi and 20 days for 3% treated kimchi. Total microbes were reduced, but lactic acid bacteria counts were higher in the treated group. CaL treated kimchi showed higher AIS content and firmer texture, which was more conspicuous in the 2 and 3% CaL treated groups. Calcium content in kimchi fermented for 15 days was 40.75～41.53 mg%, which is 42～45% higher than that in the control group. The sodium content was 23～54% less in the treated groups. The epidermis and vascular bundle tissue of kimchi fermented for 15 day was damaged more severely in the control group than in the treated group. CaL treated kimchi has a crispier taste and the development of sour taste was delayed. Therefore, addition of CaL can produces a kimchi with high calcium as well as superior texture and shelf-life, when adjusting the concentration according to the fermentation periods.

• Journal of Microbiology and Biotechnology
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• v.21 no.2
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• pp.162-169
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• 2011

A dynamic model of lactic acid fermentation using Lactococcus lactis was constructed, and a metabolic flux analysis (MFA) and metabolic control analysis (MCA) were performed to reveal an intensive metabolic understanding of lactic acid bacteria (LAB). The parameter estimation was conducted with COPASI software to construct a more accurate metabolic model. The experimental data used in the parameter estimation were obtained from an LC-MS/MS analysis and time-course simulation study. The MFA results were a reasonable explanation of the experimental data. Through the parameter estimation, the metabolic system of lactic acid bacteria can be thoroughly understood through comparisons with the original parameters. The coefficients derived from the MCA indicated that the reaction rate of L-lactate dehydrogenase was activated by fructose 1,6-bisphosphate and pyruvate, and pyruvate appeared to be a stronger activator of L-lactate dehydrogenase than fructose 1,6-bisphosphate. Additionally, pyruvate acted as an inhibitor to pyruvate kinase and the phosphotransferase system. Glucose 6-phosphate and phosphoenolpyruvate showed activation effects on pyruvate kinase. Hexose transporter was the strongest effector on the flux through L-lactate dehydrogenase. The concentration control coefficient (CCC) showed similar results to the flux control coefficient (FCC).