• Korean Journal of Animal Reproduction
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• v.11 no.3
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• pp.155-160
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• 1987

This study was carried out to determine the effects of cryoprotectants, freezing and thawing rates on the survival of 8-cell mouse embryos. The female ICR mice were induced to superovulated by intraperitoneal injections of 5 i.u. PMSG and 5 i.u. HCG given 48h apart and then were paired with males of the same strain. They were killed and embryos were flushed from the oviducts and uteri on 3 days after injection of HCG. Embryos were flushed with modified Dulbecco's phosphate buffered saline and equilibrated with 1.5M-dimethyl sulfoxide (DMSO) or 1.5M-glycerol by 3-step procedure. The freezing rates of the embryos were 1$^{\circ}C$/min from room temperature to -5$^{\circ}C$ and the embryos were seeded at -5$^{\circ}C$. After being held for 3 min at the seeding temperature, the rates were 0.3$^{\circ}C$/min from -5$^{\circ}C$ to -35$^{\circ}C$. From -35$^{\circ}C$ to -7$0^{\circ}C$, the rates were divided into 0.1$^{\circ}C$/min, 1$^{\circ}C$/min and 1$0^{\circ}C$/min, respectively. After being held for 5 min at -7$0^{\circ}C$, the embryos were plunged directly into liquid nitrogen. The embryos were thawed at 4$^{\circ}C$/min and 12$^{\circ}C$/min from -196$^{\circ}C$ to 37$^{\circ}C$, and for 2 min in 37$^{\circ}C$ water bath, respectively. The average number of ovulation points and embryos recovered were 42.7 and 34 appearing 79.5% recovery rate. Eight cell embryos in the embryos recovered were 26.3. The survival rates of embryos according to the freezing rates in the presence of 1.5M-DMSO were 73.5~80.6% at 0.1$^{\circ}C$/min, 75.0~79.5% at 1$^{\circ}C$/min and 52.8~54.7% at 1$0^{\circ}C$/min, but in the presence of 1.5M-glycerol were 62.9~67.6% at 0.1$^{\circ}C$/min, 61.4~68.3% at 1$^{\circ}C$/min and 25.5~30.2% at 1$0^{\circ}C$/min. The survival rates of embryos were not affected by the thawing rates.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.514-522
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• 2017

Objective: The study aimed to assess the N use efficiency (NUE) of pig slurry (in comparison with chemical fertilizer) for each regrowth yield and annual herbage production and their nutritive value. Methods: Consecutive field experiments were separately performed using a single application with a full dose of N (200 kg N/ha) in 2014 and by four split applications in 2015 in different sites. The experiment consisted of three treatments: i) control plots that received no additional N, ii) chemical fertilizer-N as urea, and iii) pig-slurry-N with five replicates. Results: The effect of N fertilization on herbage yield, N recovery in herbage, residual inorganic N in soil, and crude protein were significantly positive. When comparing the NUE between the two N sources (urea and pig slurry), pig slurry was significantly less effective for the earlier two regrowth periods, as shown by lower regrowth dry matter (DM) yield, N amount recovered in herbage, and inorganic N availability in soil at the 1st and 2nd cut compared to those of urea-applied plots. However, the effect of split application of the two N sources was significantly positive at the last two regrowth periods (at the 3rd and 4th cut). The two N sources and/or split application had little or no influence on neutral detergent fiber (NDF) content, acid detergent fiber (ADF) content, and in vitro DM digestibility, whereas cutting date was a large source of variation for these variables, resulting in a significant increase in in vitro DM digestibility for the last two regrowth periods when an increase in NDF and ADF content occurred. Split application of N reduced the N loss via nitrate leaching by 36% on average for the two N sources compared to a single application. Conclusion: The pig slurry-N was utilized as efficiently as urea-N for annual herbage yield, with a significant increase in NUE especially for the latter regrowth periods.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.53-60
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• 2015

Newly, nutrients recovery by bioconversion in the swine waste which caused serious problems due to its high organic fraction and content of nutrients such as phosphorus and nitrogen is viewed as a considerable approach since it produces valuable product as well as recycling of resources. Consequently, it is necessary to find new methods to treat swine waste. One possible solution to this problem is to use this potential pollutant as a growth substrate for economically valuable products. The study for the fundamental improvement of bioconversion efficiency by finding optimum growth conditions using statistical models and biotechnology was performed. A novel approach to utilize swine waste by cultivating mycelia of the mushroom Phellinus linteus are described. A central composite face-centered design (CCF) for the experiments was used to develop empirical model providing a quantitative interpretation of the relationships among the three variables, which were substrate concentration, pH, and temperature. The maximal radial extension rate (2.78mm/d) of P.linteus was determined under the condition of 5.0 g COD/L, pH 5.0, and temperature $29.7^{\circ}C$. The results of this study suggest that swine waste could be utilized as a growth substrate for the cultivation of mushroom mycelia enhancing an efficiency of utilizing this by-product of the livestock industry.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.436-445
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• 1986

As the second part of the studies on the utilization of polyunsaturated lipids in sardine oil as nutritional or medical supplement, the conditions of lipid extration and concentration, refining, and storage stability of EPA-condensed sardine oil were investigated. In extraction of lipids, solvent ratios of chloroform-methanol mixture(2:1 v/v) affected the final content of unsaturated lipid in extracted oil and recovery. Stepwise solvent fractionation method at various low temperatures was effective to concentrate polyenoic acids like EPA and DHA when acetone or acetone-methanol mixture, added in the ratio of 1:5 (v/v) was applied step by step to different temperatures at 0 to $-35^{\circ}C$. Addition of 1 to $5\%$ (v/v) of water to acetone was also benefit to raise EPA content but that resulted in reducing the yield of condensed oil from $65\%\;to\;28\%$. Concentration rate of polyenoic acids by solvent fractionation in lipid-actone solution (1:5, v/v) at 0 to $-30^{\circ}C$ seemed limited to $5{\sim}8\%$ in fatty acid composition depending on the initial content of those polyenoic acids in the sardine oil. During the extraction, concentration, and alkaline treatment, oxidation was rapidly induced but oxidation products could be thoroughly removed on the process of deceleration and peroxide elimination. To stabilize the reactive polyenoic acid condensed oil during the storage, stuffing nitrogen gas was essential to expel dissolved oxygen in oil or to seal the oil from open air, and the addition of antioxidative agents as BHA and tocopherols were greatly helpful to extend the storage life.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.29-35
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• 2009

This study was to determine the effects of ascorbic acid and alpha-tocopherol on the attenuation of an ischemia-reperfusion injury (IRI) after renal auto-transplantation in a pig model. In the treatment group, three pigs were subjected to a renal auto-transplantation followed by the administration of ascorbic acid and alpha-tocopherol and the flushing of ascorbic acid plus hepa-saline solution. Otherwise, the control group used only flushing of hepa-saline solution. Blood samples were collected from these pigs for measurement of serum blood urea nitrogen (BUN) and creatinine values on the day before surgery and day 1, 3, 5 and 7 after surgery. The kidneys were taken for histopathological evaluation following euthanasia on day 14 after surgery. Serum creatinine and BUN values showed a significantly difference between control and treatment group on day 1, 3 and 5 (P<0.05). In histopathologic findings, treatment group showed less damage than that of the control group on the basis of renal tubular damage. As a result, this study suggests that the exogenous ascorbic acid and alpha-tocopherol pretreatment therapy with ascorbic acid irrigation-aspiration has a role of attenuation of renal I/R injury and recovery of renal function in a pig transplantation model.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.272-279
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• 2002

A field experiment was conducted to investigate the effect of N-use efficiency and rice yield by rapeseed cake(organic fertilizer) application at panicle initiation stage in machine transplating cultivation from 1999 to 2000. The rice yield increased by 4% in "50% rapeseed cake application", by 2% in "30% rapeseed cake application" at panicle initiation stage, respectively. Amount of fertilizer N uptake was high according to increasing amount of rapeseed cake application at panicle initiation stage compared with conventional treatment, but percentage recovery of fertilizer N was higher in 30% rapeseed cake application than in 50% rapeseed cake application at panicle initiation stage. Thus, this result was thought that there was more adventageous in 30% rapeseed cake application than 50% rapeseed cake application at panicle initiation stage in the fertilizer reduction or N-use efficiency respects in rice paddy.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.564-569
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• 1992

A green sulfur bacterium, Chlorobium limicola f. thiosulfatophilum NCIB 8327, was grown in modified Pfennig's medium including glu1amate as a nitrogen source. Glutamine synthetase was isolated through a series of ultracentrifugation. DEAE-Sepharose CL-6B ion exchange chromatography. Sephacryl S-300 gel permeation chromatography, and preparative HPLC. The recovery and purification fold of the enzyme were 2% and 46.3. respectively. The isolated enzyme was homogeneous on UV-Visible spectrum and polyacrylamide gel electrophoretogram. The relative molecular mass of the native enzyme was estimated to be 280,000 by gel permeation chromatography. The enzyme consisted of ten subunits with relative similar molecular mass. 30.000. which was estimated by SDS-polyacrylamide gel electrophoresis. The optimal temperature and pH of the enzyme were $30^{\circ}C$ and 7.0. Km values were 27.9 mM for L-glutamine and 0.92 mM for hydroxylamine-HCr. The enzyme activity was inhibited by alanine. glycine. and tryptophan considerably, but was not affected by asparagine, lysine. leucine. and valine.

• Journal of Environmental Science International
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• v.15 no.1
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• pp.85-94
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• 2006

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in sinseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by CC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with $70\%$ acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography $(3\times30cm)$ packed with florisil $(30g,\;130^{\circ}C,\;12hrs)$. The final extract was concentrated in a rotator evaporator at $40^{\circ}C$ until dryness. Then the residue was redissolved to 2ml with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over $1\~10{\mu}g/ml$. The recovery tests were ranged from $70.7\%$ to $115.2\%$ with standard deviations between 0.3 and $5.7\%$ of the standard spiked to the ginseng extract sample (Group $I\~IV$). The limit of detection (LOD) ranged from 0.001 to $0.099{\mu}g/ml$ (Group $I\~IV$). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.

• Journal of Sensor Science and Technology
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• v.29 no.1
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• pp.14-18
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• 2020

This study investigates the nitrogen dioxide (NO₂) sensing characteristics of an Si MOSFET gas sensor with a tungsten trioxide (WO₃) sensing layer deposited using the sputtering method. The Si MOSFET gas sensor consists of a horizontal floating gate (FG) interdigitated with a control gate (CG). The WO₃ sensing layer is deposited on the interdigitated CG-FG of a field effect transistor(FET)-type gas sensor platform. The sensing layer is deposited with different thicknesses of the film ranging from 100 nm to 1 ㎛ by changing the deposition times during the sputtering process. The sensing characteristics of the fabricated gas sensor are measured at different NO₂ concentrations and operating temperatures. The response of the gas sensor increases as the NO₂ concentration and operating temperature increase. However, the gas sensor has an optimal performance at 180℃ considering both response and recovery speed. The response of the gas sensor increases significantly from 24% to 138% as the thickness of the sensing layer increases from 100 nm to 1 ㎛. The sputtered WO₃ film consists of a dense part and a porous part. As reported in previous work, the area of the porous part of the film increases as the thickness of the film increases. This increased porous part promotes the reaction of the sensing layer with the NO₂ gas. Consequently, the response of the gas sensor increases as the thickness of the sputtered WO₃ film increases.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.459-468
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• 2011

The main purpose of this study was to examine the influence of treatment amounts of Slurry Composting and Biofiltration liquid fertilizer (SCBLF) on biomass growth of Yellow poplar (Liriodendron tulipifera) and to compare bioethanol production from the harvested wood. Relative growth rate, biomass production and leaf characteristics were significantly enhanced by SCBLF treatment and medium treatment plot showed highest value. Nitrogen compounds and water content in SCBLF affected to increase chlorophyll contents which led improving biomass production (64.67%) and glucose contents (6.07%) than control. Organosolv and dilute acid pretreatments were preliminarily carried for bioethanol production, and the pretreatment processes were conducted at all the same solid to liquid ratio (1 : 10), reaction temperature ($150^{\circ}C$), preheating time (40 min) and residence time (10 min). The water insoluble solid recovery of Organosolv pretreatment with 1% sulfuric acid as a catalyst was the lowest and that of medium treatment plot was 44.81%. Exchangeable cations in SCBLF might be affected to increase pretreatment effect. The simultaneous saccharification and fermentation process was followed to determine the ethanol production of the pretreated biomass. The highest ethanol production yield based on initial weight was obtained from high treatment plotby Organosolv pretreatment with 1% sulfuric acid (16.11%). But regarding biomass production, medium treatment plot produced most, and bioethanol production was increased by 72.93% than control.