• 한국수정란이식학회지
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• 제18권1호
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• pp.1-14
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• 2003

본 연구는 미성숙, 성숙 단계의 돼지 난포란이 유리화 동결에 의한 동결보존이 가능한지를 조사 하고자 실시하였다. 난포란은 세포질 내 지방구를 분극시키기 위해 원심분리를 실시하였고, 미세조작기를 이용하여 지방구를 제거하였다. 돼지 난포란을 CB 처리하여 원심분리 후 지방구를 제거한 지방제거구(Delipated), CB 처리 후 원심분리만 하여 지방구를 분극시킨 원심분리구(Centrifuged), 아무처리도 하지 않은 대조구(Control)를 EM grid를 이용한 유리화 동결, 융해 한 후 생존율과 체 외 발생율을 조사하였다. 그 결과를 요약하면 다음과 같다. 1. 미성숙 시기에 지방제거, 원심분리, 무처리 후 유리화 동결을 실시한 돼지 난포란의 생존율은 각각 15.1%, 0%, 0%로 지 방제 거구에서만 유의적으로 높은 생존율을 나타내었다(p<.01). 2. 성숙 시기에 지방제거, 원심분리, 무처리 후 유리화 동결을 실시한 돼지 난포란의 생존율은 각각 12.2%, 0%, 0%로 지방제거구에서만 유의적으로 높은 생존율을 나타내었다(P<.01). 3. 미성숙 시기에 지방제거 후 유리화 동결을 실시하여 생존한 난자치 핵 성숙율은 37.5%로 동결하지 않은 난포란의 성숙율 68.9%보다 유의적으로 낮은 것이었다(P<.01). 4. 미성숙 시기에 지방제거, 원심분리, 무처리 후 유리화 동결을 실시하여 생존한 난자의수정 후 배 발달율은 12.5%, 0%, 0%로 지방 제거구에서만 배 발달을 나타었으나, 세 처리간의 유의차는 없었고, 이것은 동결하지 않은 난포란의 배 발달율 56.1%보다는 유의 적으로 낮은 것이었다(P<.05). 5. 성숙 시기에 지방제거, 원심분리, 무처리 후 유리화 동결을 실시하여 생존한 난자의 수정 후 배 발달율은 25.0%, 0%, 0%로 지방제거구에서만 배 발달을 나타내었으나 세 처리간의 유의차는 없었고, 이것은 동결하지 않은 난포란의 배 발달율 67.9%보다는 유의적으로 낮은 것이었다(P<.05).

• 한국축산식품학회지
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• 제37권6호
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• pp.799-803
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• 2017

In the present study, centrifugation and filtration pretreatments were evaluated to decrease sample preparation time and to improve the sensitivity and specificity of multiplex polymerase chain reaction (PCR) for the detection of low levels of pathogenic Escherichia coli in various foods. Pathogenic E. coli (E. coli NCCP11142, E. coli NCCP14037, E. coli NCCP 14038, E. coli NCCP14039, and E. coli NCCP15661) was inoculated into pork, beef, and baby leafy vegetables at 1, 2, and 3 Log CFU/g. The samples were shaken 30 times (control), then centrifuged or filtered. DNA extracts from the samples were subjected to PCR using the $Powerchek^{TM}$ Diarrheal E. coli 8-plex Detection Kit. In the pork samples, no E. coli was detected in the control samples, while E. coli were detected in 100% of 3-Log CFU/g inoculated and centrifuged samples, and in 100% of 2 and 3-Log CFU/g inoculated, and filtered samples. In the beef samples, all control samples appeared to be E. coli-negative, while E. coli was detected in 50-75% of centrifuged samples, regardless of inoculated level, and in 100% of 2 and 3-Log CFU/g inoculated, and filtered samples. In baby leafy vegetables, E. coli were not detected in 25-50% of the control samples, while E. coli were detected in 0-25% of the centrifuged samples, and 75-100% of the filtered samples, depending on the inoculum amount. In conclusion, filtration pretreatment can be used to minimize sample preparation time, and improve the sensitivity and specificity of rapid detection of pathogenic E. coli in various foods.

• Asian-Australasian Journal of Animal Sciences
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• 제15권12호
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• pp.1725-1731
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• 2002

The distribution and activities of hydrolytic enzymes (cellulolyti, hemicellulolytic,pectinolytic and others) in the rumen compartments of Hereford bulls fed 100% alfalfa hay based diets were evaluated. The alfalfa proportion in the diet was gradually increased for two weeks. Whole rumen contents were processed into four fractions: Rumen contents including both the liquid and solid fractions were homogenized and centrifuged, and the supernatant was assayed for enzymes located in whole rumen contents (WRE); rumen contents were centrifuged and the supernatant was assayed for enzymes located in rumen fluids (RFE); feed particles in rumen contents were separated manually, washed with buffer, resuspended in an equal volume of buffer, homogenized and centrifuged and supernatant was assayed for enzymes associated with feed particles (FAE); and rumen microbial cell fraction was separated by centrifugation, suspended in an equal volume of buffer, sonicated and centrifuged, and the supernatant was assayed for enzymes bound with microbial cells (CBE). It was found that polysaccharide-degrading proteins such as $\beta$-1,4-D-endoglucanase, $\beta$-1,4-D-exoglucanase, xylanase and pectinase enzymes were located mainly with the cell bound (CBE) fraction. However, $\beta$-D-glucosidase, $\beta$-D-fucosidase, acetylesterase, and $\alpha$-L-arabinofuranosidase were located in the rumen fluids (RFE) fraction. Protease activity distributions were 37.7, 22.1 and 40.2%, and amylase activity distributions were 51.6, 18.2 and 30.2% for the RFE, FAE and CBE fractions, respectively. These results indicated that protease is located mainly in rumen fluid and with microbial cells, whereas amylase was located mainly in the rumen fluid.

• Applied Biological Chemistry
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• 제37권3호
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• pp.168-174
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• 1994

여과 및 원심 분리가 $70^{\circ}C$ 저장 중 참기름의 산화 안정성에 미치는 영향을 headspace gas chromatography법에 의한 헥산알 생성과 기름의 과산화물가 및 공액 이중 결합 측정에 의해 살펴보았다. 볶은 참깨로부터 얻은 조참기름은 유리지방산, 공액 이중결합과 금속(철, 구리, 마그네슘 및 아연)을 더욱 많이 함유한 반면 수분과 ${\gamma}-tochopherol$은 여과 참기름 또는 원심분리 참기름에 더 많이 함유되었다. 여과 참기름은 세 종류의 기름 중 가장 큰 L과 b값의 우수한 색도에도 불구하고 조참기름보다 많은 과산화물을 함유하였다. 모든 참기름이 $70^{\circ}C$ 저장 중 색차가 증가하는 경향을 보였으며 여과 참기름에서의 리놀렌산 감소 경향을 제외하고는 비교적 일정한 지방산 조성을 보였다. 산화 안정성에 있어서 원심분리 참기름과 조참기름은 a=1%에서 유의적인 차이를 보이지 않았으며 여과 참기름은 이들보다 산화안정성이 떨어졌다. 원심분리 참기름이 산화안정성과 유지의 색도 측면에서 가장 좋은 것으로 나타났다.

• 한국축산식품학회지
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• 제33권4호
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• pp.501-507
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• 2013

Lysozyme was trapped from $2{\times}$ diluted egg white using Amberlite FPC 3500 ion exchange resin (1 g/10mL of egg white). The lysozyme bound to the resin was recovered using 0.1 N glycine-NaOH buffers, pH 9.0, containing 0.5 M NaCl. After separating lysozyme, the pH of the egg white solution was adjusted to 4.75 and centrifuged to remove interfering proteins. The supernatant was collected, added with 2.5% citric acid and 5.0% ammonium sulfate combination to precipitate egg white proteins, except for ovalbumin. After centrifugation, both supernatant (S1) and precipitant were collected. The precipitant was dissolved with 4 volumes of distilled water, and then 2.0% ammonium sulfate and 1.5% citric acid combinations added, stirred overnight in a cold room, and centrifuged. The resulting supernatant (S2) was pooled with the first supernatant (S1), desalted using an ultrafiltration unit, heat-treated at $70^{\circ}C$ for 15 min, and then centrifuged. The supernatant was collected as an ovalbumin fraction and lyophilized. The separated proteins were confirmed using Western blotting. The yield of lysozyme and ovalbumin was > 88.9% and > 97.7%, respectively, and the purity of lysozyme and ovalbumin was > 97% and 87%, respectively. The results indicated that the protocol was simple, and separated lysozyme and ovalbumin effectively.

• 한국수정란이식학회지
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• 제19권1호
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• pp.35-42
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• 2004

본 연구는 돼지 배아의 유리화 동결 시 CB 처리군과 CB 비처리군의 영향을 비교하였다. CB의 농도별, 처리 시간별로 처리한 뒤 유리화 동결 융해 후 정상적인 형태 회수율과 생존률을 각각 조사하였다. 1. CB를 전 처리한 군과 비처리군의 정상적인 형태율이 각각 84.2%, 81.9%로 유의한 차이가 없었으나, 융해 후 72시간 째 생존률의 결과에서는 각각 60.5%, 32.8%로 유의성(p<0.1)이 검증되었다. 2. CB 농도별 생존률에 미치는 영향은 7.5 $\mu\textrm{g}$/$m\ell$의 처리군이 다른 처리군에 비하여 유의적으로 높았다(p<0.05). 정상 형태율 95%와 융해 후 생존률 73%로서 다른 농도에 비하여 65∼76%, 15∼57%보다 각각 높았다. 3. 7.5 $\mu\textrm{g}$/$m\ell$ 농도의 CB 전처리의 처리 시간에 따른 영향은 20분 처리하였을 때 정상적인 형태율은 81%로 다른 처리군(25∼69%)보다 높았고, 24시간 째 생존률의 결과로도 64%, 6∼56%로 유의적인 차이는 나타나지 않았다. 또한 원심 처리군과 비처리군에서도 CB를 20분으로 처리하였을 때 가장 좋은 결과를 나타내었으며, 원심 비처리군보다는 원심 처리군이 좀 더 높은 결과를 보여 주었다.

• Journal of Pharmaceutical Investigation
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• 제30권1호
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• pp.51-54
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• 2000

A column-switching high performance liquid chromatographic method has been developed for the determination of a fluconazole in human plasma. Each plasma sample was centrifuged for 10 min at 5000 g. After an aliqout of the supernatant was taken to nylon microcentrifuge filter, these samples were centrifuged for 10 min at 5000 g. An aliqout of the supernatant was injected directly onto the HPLC column. Deionized water was run for 2 min at a flow rate of 1.0 ml/min to retain fluconazole in an extration column, while proteins and endogenous interferences were eluted to the waste. The analyte was then back-flushed onto an analytical column, $C_{18}$ reversed-phase column. The mobile phase for analytical column, 0.01 M sodium acetate (pH 5.0)-methanol (65:35, v/v), was run at a flow rate of 1.0 ml/min. The column effluent was monitored by ultraviolet detection at 261 nm. The retention time for fluconazole was 11.76 min in human plasma. The detection limit for fluconazole in human plasma was $0.2\;{\mu}g/ml$. No interference from endogenous substances was observed.

• 대한수의사회지
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• 제17권1호
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• pp.45-50
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• 1981

The adult New Hampshire female chickens were phlebotomized and the blood heparinized was centrifuged. The packed cell volume was made and the hematocrit, per centage of the blood that is red cells, was reschuffled of $10\%,30\%,50\%, and 70\%$

• 한국식품영양학회지
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• 제2권1호
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• pp.27-31
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• 1989

Studies were conducted on the preparation methods of strawberry jam. Strawberry was homogenized and centrifuged to serum-pulp portion. Concentration of strawberry serum was carried out at 55~58$^{\circ}C$ under pressure of 30~60mmHg. Strawberry jam bases were mixed throughly and stuffed in retortable pouch, The pouch was sterilized to make a new strawberry jam. The characteristics of new type ism was analyzed gas chromatographic profile, and sensory evaluations.

• Journal of Dairy Science and Biotechnology
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• 제38권3호
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• pp.161-167
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• 2020

Cheese pizzas fortified with casein phosphopeptide (CPP) and calcium were subjected to an in vitro digestion to assess whether CPP could prevent the precipitation of calcium. The total calcium content of the cheese pizzas was adjusted to 1,000 mg per pizza (~370 g) with the addition of calcium originating from eggshells. Two levels of trypsin-digested caseins (367 and 459 mg), with a CPP content of ~20%, were added to each pizza. The in vitro digested pizzas were then centrifuged and the supernatant was mixed with Na₂HPO₃ at 37℃ to estimate the possible soluble effect of CPP on calcium. After 24 h of reaction, the solution was centrifuged and the calcium content in the resultant supernatant was analyzed by inductively coupled plasma-atomic emission spectroscopy. One-way statistical analyses showed that CPP had a positive effect on the solubilization of calcium against phosphate (p<0.05). Cheese pizza supplemented with 459 mg of CPP powder was able to prevent precipitation of calcium by 98.8%, whereas no CPP-added cheese pizza solubilized 86.4% of the calcium. A sensory test was also carried out, revealing that panelists could not discern the bitter taste of the CPP added to the pizzas.