• Korean Journal Plant Pathology
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• v.12 no.2
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• pp.182-186
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• 1996

국내에서 재배되고 있는 고추(Capsicum annuum L.)로부터 분리된 TMV pepper 계통을 density gradient centrifugation을 이용하여 순화하였다. 이로부터 바이러스의 total RNA를 분리하였고 RT-PCR에 의하여 TMV pepper 계통의 외피단백질 cDNA를 합성, 증폭하였으며 이를 pBluescript II SK- 벡터에 재조합하였다. 본 실험에서 바이러스 외피단백질과 3` non-coding region을 포함하는 재조합 클론 p1561과 p1562로부터 염기서열을 분석하였고 그 결과로 477 염기의 외피단백질 유전자를 포함하는 691 염기가 합성되었음을 확인하였으며 이것과 TMV common 계통으로부터 합성된 외피단백질 cDNA와의 최대 유사도는 69%였다. 또한 유추된 아미노산 서열에서 이들 두 계통간의 최대 유사도는 81%였다.

• The Korean Journal of Food And Nutrition
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• v.6 no.1
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• pp.31-36
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• 1993

Strawberry pulp was separated into serum and insoluble pulp by centrifugation and the serum was concentrated in vacuo to five folds at 55~58$^{\circ}C$ and 30~60mmHg. Concentrated strawberry pulp was prepared by mixing of concentrated serum and insoluble pulp. To evaluate the quality changes of straw-berry pulp, color, physicochemical and sensory properties were analyzed after concentration and during 18 weeks storage at -18'2. The results obtained from the study were as follows : during 18 weeks storage at - l8$^{\circ}C$, soluble solid, browning, reducing sugar content were increased and total anthocyanin, vitamin C, apparent viscosity were decreased. The result of sensory evaluation indicated that texture of concentrated pulp was inferior to that of control but flavor, color intensity and overall acceptance were not different from each other.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.189-194
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• 2011

Metallurgical grade silicon was recovered from slurry waste for ingot sawing process by acid leaching and thermal treatment. SiC abrasive was removed by gravity concentration and centrifugation. Metal impurities were removed by the acid leaching using HF/HCl. The remaining SiC was separated by the thermal treatment at $1600^{\circ}C$ in an inert atmosphere by the difference in melting points. The purity of the obtained silicon was found to be around 99.7%.

• KSBB Journal
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• v.11 no.1
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• pp.115-123
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• 1996

Two kinds of mutants were isolated to clone a cluster of genes essential for zooglan biosynthesis. Zoogloea ramigera 115 strains produce capsular polysaccharide. To achieve conjugation in strain 115 and to facilitate recovery of product, a capsule non-forming strain was isolated via successive centrifugation and screening. The other kind of mutants devoid of or producing altered exopolysaccharides were obtained using classical transposon(Tn5) technique and screened for altered colony morphology and celluflour binding properties. Complementation of these mutants was achieved with Z. ramigera 115 slime gene library constructed in a broad host range cosmid vector and helper plasmid by triparental conjugation.

• KSBB Journal
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• v.7 no.3
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• pp.166-171
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• 1992

Zoogloea ramigera 115 was cultured for biopolymer production and its bioflocculant usages. Cultural conditions of the organism were examined with regard to high production of the microbial polysaccharide. The most suitable medium was found to contain glucose as a carbon source, $NaNO_3$ as a nitrogen source, and yeast extract as an organic nutrient. The initial pH of 6.0 proved to optimal. The biopolymer was extracted effectively using ultrasonication and high speed centrifugation, followed by propanol addition. Jar test results indicate that the polysaccharide produced by the organism is an effective flocculant.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.75-78
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• 1999

Acetylcarnitine, a metabilite of carnitine, has been porven to be a potent inhibitor of ethanol oxidation in hepatocytes. It inhibits the activity of alcohol dehydrognase (ADH), but not the microsomal ethanol oxidizing system. which was significatly inhibited by acetylcarnitine at NAD ; acetylcarnitine $\leq$1. the main objectives of his study were to ascertain the interaction between acetylcarnitine and NAD on ADH activity and to elucidate whether different species have different effects. Tehpost-mocrosomal supernatant (PMS) was prepared from normal rat, guinea pig, mouse and broilers by differential centrifugation . Horse and yeast ADH were purchased from the Sigma Chemical Co. Prepared and purchased ADH are used for determination of ADH activity in the presence or absence of carnitine and acetylcar- nitine. Binding studies showed that acetylcarnitine did bind to ADH in a dose realted manner when low NAD ; acetylcar- nitine ratio was provided. It was found that the inhibitionof ADH activity occurred only when NAD concentration was less than the inhibitor concentration . Crystalline and crude ADH preparation from different vertebrate species wer inhibited by acetylcarnitine, whereas the yeast ADH was not affected by acetylcarnitine.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.95-97
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• 2004

An angiotensin converting enzyme (ACE) inhibitory substance was isolated and purified from Lycium chinense Miller. A crude water extract of Lycium chinense Miller was prepared by adding it to water shaking at $25^{\circ}C$ for 1 hr, followed by centrifugation at 8000 ${\times}$ g for 30 min. The crude extract was then filtered using YM-3 and YM-1 membranes. An ACE inhibitor was isolated using consecutive chromatographic methods including: ion exchange chromatography, gel permeation chromatography, and FPLC. The inhibitor was identified to have a molecular mass of 862 daltons by mass spectrometry.

• Journal of Powder Materials
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• v.18 no.3
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• pp.297-302
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• 2011

Colloidal stability is one of crucial factors for many applications of nanodiamond. Despite recent development, nanodiamonds available on the market often exhibit a high impurity content, wide size distribution of aggregates and low resistance to sedimentation. In the current study, four commercial nanodiamond powders synthesized by detonation synthesis were surface modified and then separated with respect to the size into six fractions by centrifugation. The fractions were evaluated by zeta potential, particle size distribution and elemental composition. The results showed that the modified nanodiamonds form stable colloidal suspensions without sedimentation for a long time.

• Journal of Microbiology and Biotechnology
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• v.3 no.4
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• pp.261-265
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• 1993

A sopA protein (41K) encoded by plasmid pXX288 was observed in the cytoplasm, whereas a sopB protein (37K) encoded by plasmid pXX157 was observed in the membrane fraction. Most of the sopB protein was solubilized from the crude membrane by treatment with Sarkosyl, which suggested that the protein may be located in the inner membrane. The sopA protein was precipitated at the concentration of 30 to 60% ammonium sulfate. The sedimentation profile of the crude membrane fraction showed a little difference according to culture media used, and the sopB protein existed in all fractions of inner membrane. The DNA of plasmids, pXX157, pXX300, and pXX167 co-sedimented with inner membrane fraction.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.1 no.1
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• pp.46-52
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• 2015

Herein we present the synthesis of $^{68}Ga$-labeled gold nanoparticles for in vivo PET imaging. A novel chelator DTPA-Cys was easily prepared from diethylenetriaminepentaacetic dianhydride in high yield. The ${\alpha}_v{\beta}_3$ integrin receptor targeted gold nanoparticle probe was synthesized by using DTPA-Cys, polyethylene glycol and cRGD peptide. $^{68}Ga$ labeling of cRGD conjugated gold nanoparticle was carried out at $40^{\circ}C$ for 30 min. Observed radiochemical yield was more than 75% as determined by radio-TLC and the probe was purified by centrifugation. In vitro stability test showed that 90% of $^{68}Ga$-labeled gold nanoparticle probe was stable in FBS for 1 h. Those results demonstrated that $^{68}Ga$-labeled gold nanoparticle could be used as a potentially useful probe for specific tumor imaging.