• 한국응용과학기술학회지
• /
• 제14권3호
• /
• pp.97-101
• /
• 1997

An intracellular, soluble 1,4-benzoquinone reductase was purified from Baker's Yeast by ammonium sulfate precipitation, DEAE-Sephacel anion exchange chromatography, and Sephacryl S-200 gel filtration chromatography. 1,4-Benzoquinone reductase was achieved 123.8 fold purification from crude homogenate with a yield of 11.1%.

• Bulletin of the Korean Chemical Society
• /
• 제33권10호
• /
• pp.3298-3302
• /
• 2012

Although offline enrichment of phosphorylated peptides is widely used, enrichment for phosphopeptides using $TiO_2$ is often performed manually, which is labor-intensive and can lead to irreproducible results. To address the problems associated with offline enrichment and to improve the effectiveness of phosphopeptide detection, we developed an automated online enrichment system for phosphopeptide analysis. A standard protein mixture comprising BSA, fetuin, crystalline, ${\alpha}$-casein and ${\beta}$-casein, and ovalbumin was assessed using our new system. Our multidimensional system has four main parts: a sample pump, a 20-mm $TiO_2$-based column, a weak anion-exchange, and a strong cation-exchange (2:1 WAX:SCX) separation column with LC/MS. Phosphorylated peptides were successfully detected using the $TiO_2$-based online system with little interference from nonphosphorylated peptides. Our results confirmed that our online enrichment system is a simple and efficient method for detecting phosphorylated peptides.

• 한국식품영양학회지
• /
• 제16권2호
• /
• pp.152-157
• /
• 2003

Serratia marcescen ATCC 25419 protease를 ammonium sulfate treatment, DEAE-cellulose anion exchange chromatography등의 방법으로 정제하였는데 최종 단계에서 667.5 unit/mg 이었으며 회수율은 43%이었고 448배 정제되었다. 정제한 S. marcescens protease로부터 아포효소를 만든 후 금속 재활성화에 대해 조사하였다. S. marcescens protease는 EDTA에 의해 완전히 활성을 잃는 metalloenzyme이며 Hg, Fe, Cu 등에 의해서 효소 활성을 70% 이상 잃은 반면, Co는 효소 활성을 약 20% 정도 증가시켰다. 아포효소의 재활성화는 pH 6~8에서 Mn, Co, Zn 등이 효과적이었다. Mn, Co, Zn등을 아포효소에 가하여 만든 효소들 중에서 Zn-효소는 효소 활성도, 알칼리-불활성화, 열-안정성 면에서 원래 protease와 유사하였다.

• 약학회지
• /
• 제41권5호
• /
• pp.638-646
• /
• 1997

The steroid 9${alpha}$-hydroxylase activity has been detected in cytosol fraction, $100,00{\times}g$ supernatant of cell free extract of Mycobacterium fortuitum. The activity was not linear with protein concentration in the assay suggesting 9${alpha}$-hydroxylase is a multicomponent enzyme. The 9${alpha}$-hydroxylase system was partially purified through fractional saturation of ammonium sulfate, strong anion exchange (Mono Q) column chromatography, gel filtration (Superose 12) column chromatography, and testosterone affinity gel chromatography. Ammonium sulfate 50~60% saturated fraction of the cytosol gave 9${alpha}$-hydroxylase activity. For further purification, the half-saturated ammonium sulfate fraction was applied to Mono Q, Superose 12, or affinity gel column. The purification factors of 9${alpha}$-hydroxylase containing fraction after Mono Q, Superose 12, and affinity gel chromatography was 13, 11, and 17 respectively.

• 한국수소및신에너지학회논문집
• /
• 제19권2호
• /
• pp.124-131
• /
• 2008

Crude cytoplasmic fraction of phototrophic purple sulfur bacterium, Thiocapsa roseopersicina NCIB 8347, were initially prepared and purified by sonication, ultracentrifugation, ammonium sulfate fractionation and heat-treatment and it has been previously reported. Using various applications of chromatography far the purification of membrane-bound and soluble hydrogenases from heat-treated enzyme fraction were studied at present report. When the heat-treated enzyme preparation was applied to the anion column chromatography using Q-sepharose, Fraction I and II, which were extracted with the KCl 0-0.5 M gradient, showed the specific evolution hydrogenase activity 3.86 and 2.27 U/mg-protein respectively. Specific hydrogenase activitys of Fraction I and II were further increased to 4.35 and 7.46 U/mg-protein for Fraction I and to 2.49 and 4.41 U/mg-protein fur Fraction II respectively, when hydrophobic interaction column, Phenyl superose, and anion exchange column, Mono-Q, were applied. Size exclusion chromatography using superdex 200 concentrated the hydrogenase Fraction I and II to 9.19 and 7.84 U/mg-protein respectively at the final step of purification.

• Bulletin of the Korean Chemical Society
• /
• 제32권6호
• /
• pp.2039-2044
• /
• 2011

A semi-continuous and automated method for quantifying atmospheric ammonia at the parts per billion level has been developed. The instrument consists of a high efficiency diffusion scrubber, an electrolytic on-line anion exchange device, and a conductivity detector. Water soluble gases in sampled air diffuse through the porous membrane and are absorbed in an absorbing solution. Interferences are eliminated by using an anion exchange devises. The electrical conductivity of the solution is measured without chromatographic separation. The collection efficiency was over 99%. Over the 0-200 ppbv concentration range, the calibration was linear with $r^2$ = 0.99. The lower limit of detection was 0.09 ppbv. A parallel analysis of Seoul air over several days using this method and a diffusion scrubber coupled to an ion chromatography system showed acceptable agreement, $r^2$ = 0.940 (n = 686). This method can be applied for ambient air monitoring of ammonia.

• 약학회지
• /
• 제45권4호
• /
• pp.347-351
• /
• 2001

A rapid and sensitive method for the determination of glyphosate, a phosphated amino acid herbicide, in whole blood is presented. After removal of protein, the whale blood was purified by using the anion exchange resin (Dowex 1), and derivatized with 9-fluorenylmethyl chloroformate (FMCL). Derivatized glyphosate from blood sample was injected onto a Whatman partisil 10SAX column and separated with 0.1M phosphate buffer (pH 2.5) and acetonitrile (ratio=3:1). The high performance liquid chromatography-fluorescence detection gave the detection limit of 86pg and linearity of 0.9999 in the range of 0.25 $\mu$g/ml and 25 $\mu$g/ml. The recoveries of glyphosate added to the blood samples were ranged from 75.3% to 100.4% compared to the samples prepared in water. The derivatized glyphosate was stable at various acidity and temperature. This method has been successfully applied to the blood samples of lethal intoxication with the herbicide glyphosate.

• 대한화학회지
• /
• 제18권5호
• /
• pp.358-362
• /
• 1974

벤조산과 그 유도체들에 대한 음이온 교환분리를 여러 농도의 염화니켈-메탄올 용매 내에서 연구하였다. Amberlite CG-400, $Cl^-$ form에 대한 유기산들의 부피분배계수를 측정하고 이 분배계수로부터 제시된 적절한 농도의 $NiCl_2-MeOH$ 용액을 용리액으로 사용하여 몇 개의 혼합유기산을 정량적으로 분리하였다. 모든 유기산들의 농도는 자외선 분광광도계를 사용하여 정량하였다.

• Parasites, Hosts and Diseases
• /
• 제29권3호
• /
• pp.259-266
• /
• 1991

폐흡충 성충의 인산완충액 추출액을 원심분리하여 만든 세포질 현탁액을 조효소(조효소)로 사용하여 Xanthine- zanthine oxidase system으로 superoxide digmutase 환성을 측정한 결과 비활성도(비활성도: specific activity)는 4.3 units/mg이었다. 이 효소의 활성도를 30∼85% ammonium sulfate 침전 및 DEAE-Trisacryl M anion exchange chromatography와 Sephadex G-100 column chromatography를 통과시키면서 측정하는 방법으로 superoxide dismutase를 정제하고, 정제한 효소의 생화학적 특성을 관찰하여 다음과 같은 결과를 얻었다. 1. 정제과정을 통해 세포질 내 superoxide dismutase를 150배 정제하였다. Sephadex G-100 gel filtration에 의해 계산한 이 효소의 분자량은 34kDa이었고 환원성 SDS-PAGE상 subunit가 17 kDa이었다. 따라서 이 효소는 subunit 두개로 구성된 중항체로 판단하였다. 3. 이 효소는 1 mM 이상의 cyanide 농도에서는 효소 황성이 100% 억제되었고, 5mM 농도의 azide에서는 11.1%, 10mM azide에서는 22.2% 그 환성이 각각 억제되었다. 3. 이 효소는 완충액의 pH가 10.0일 때 효소 황성이 5.4배 증가되었다. 이상의 결과로 폐흡충의 세포질 내에 존재하는 superoxide dismutase는 구리와 아연을 함유한 superoxide dismutase라고 판단할 수 있었다.

• 한국미생물·생명공학회지
• /
• 제16권5호
• /
• pp.335-342
• /
• 1988

하이브리도마를 쥐의 복강이나 in-vitro에서 배양한 뒤 생산된 IgG1 type의 쥐 단일클론 항체를 정제하기 위하여 음이온 교환 크로마토그래피를 이용하였다. 배양이 끝난 배지를 원심분리하여 세포를 제거하고 50-60% ammonium sulfate로 침전물을 만든 다음 0.025M Tris-HCI(pH8.2)용액으로 투석하여 salt가 제거된 sample을 DEAE-Trisacryl M에 부하하였다. Column에 결합된 항체는 30-40mM NaCl 을 포함하는 0.025M Tris-HCI(pH8.2)용액으로 용출하였다. 혈청농도가 높은 배지 (10% FBS)에서는 50% ammonium sulfate 처리로 90% 이상의 항체가 회수되었으나 저혈청 배지 (2% FBS)에서는 60% ammonium sulfate 처리에도 회수율이 84%에 그쳤다. 후자의 경우 한외여과법 (ultrafiltration)을 이용하여 항체 회수율을 91%까지 증가시킬 수 있으나 농축된 항체를 크로마토그래피로 정제하였을 때 그순도가 ammonium sulfate 침전법에 비해 낮아졌다. 하이브리도마 Alps 25-3, HCGK, A4W, KW를 여러가지 배양조건에서 배양한 뒤 생산된 항체를 DEAE-Trisacryl M chromatography를 이용하여 정제해 본 결과 대체로 순도 70-80%의 항체를 얻을 수 있었고 이때 항체 회수율은 65% 선이었다. 항체의 순도를 높이기 위해서는 affinity chromatography 혹은 gel filtration과 같은 2차적인 방법이 필요 할 것으로 보이며 한 예로 affinity chromatography를 이용하여 순도 95%의 항체를 얻었다.