• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• 상하수도학회지
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• 제18권6호
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• pp.785-793
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• 2004

Coagulation has been investigated for pretreatment of low-pressure membrane systems such as microfiltration and ultrafiltration. Coagulation pretreatment can reduce foulants (particles and organic matter) prior to membrane filtration. However, when in-line coagulation or submerged type of filtration is used, flocculent aggregates could act as a foulant depending on concentrations and specific properties of floc. A natural water and three synthetic waters were used to investigate effects of coagulation pretreatment and presence of flocculent aggregates on membrane fouling. Coagulation pretreatment shows that foul ants were effectively removed during coagulation and the formed cake layer on the membrane surface had less resistances compared to raw natural water. In addition, little difference in membrane fouling was found by flocculent aggregates from the natural water. Interestingly, however, the results by three synthetic waters indicated that flocculent aggregates could have adverse effects on membrane fouling in a specific condition.

• 생약학회지
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• 제24권4호
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• pp.289-295
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• 1993

Polysaccharides fractions from the leaves of Artemisia selengensis$(ASP_1)$ and Artemisia iwayomogi$(ASP_1)$ were extracted and purified by Sephadex gel filtration and DEAE-Sephadex ion exchange chromatographies. Both $ASP_1$ and $AIP_1$ fractions were tested for their effects on the spleen cell culture in vitro. Both $ASP_1$ and $AIP_1$ fractions allow growth of spleen cells up to 3 months in culture, suggesting the immunoregulatory activities of those polysaccharide fractions. The molecular weights of $ASP_1$ and $ASI_1$ fractions were found to be about 2,500 daltons by Sephadex gel filtration chromatography using standard dextrans. Both $ASP_1$ and $AIP_1$ fractions were composed of glucose, xylose and galactose.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.140-147
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• 2004

Urokinase is an enzyme with fibrinolytic activity (plasminogen activator) isolated from fresh urine of healthy men. Viral safety is an important prerequisite for clinical preparation of the protein from urine. In order to increase the viral safety of a high purity urokinase in regard to non-enveloped viruses, a virus removal process using a novel polyvinylidene fluoride membrane filter (Viresolve NFP) has been optimized. Urokinase was able to pass through the filter with recoveries of 95% in the production scale process. No substantial changes were observed in physical and biochemical characteristics of the filtered urokinase in comparison with those of the enzyme before filtration. A 47-mm disk membrane filter was used to simulate the process performance of the production scale cartridges and tested if it could remove several experimental model viruses for human pathogenic viruses, including porcine parvovirus (PPV), human hepatitis A virus (HAV), murine encephalomyocarditis virus (EMCV), bovine viral diarrhoea virus (BVDV), and bovine herpes virus (BHV). Non-enveloped viruses (PPV, HAV, and EMCV) as well as enveloped viruses (BVDV and BHV) were completely removed during filtration. The log reduction factors achieved were $\geq$4.86 for PPV, $\geq$4.60 for HAV, $\geq$6.87 for EMCV, $\geq$4.60 for BVDV, and $\geq$5.44 for BHV. These results indicate that the virus filtration process successfully improved the viral safety of the final products.

• 약학회지
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• 제38권6호
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• pp.687-695
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• 1994

Lectin from mistletoe(Viscum coloratum) fermented by Lactobacillus plantarum for 1,2,3 days were obtained by salt fractionation, gel filtration, anion exchange chromatography and SDS-PAGE, and compared with the lectin from unfermented mistletoe. The new lectin of molecular weight of about 18,500D from fermented mistletoe was identified.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 춘계 총회 및 학술발표회
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• pp.23-31
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• 2002

No Abstract, See Full-text

• 미생물학회지
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• 제32권4호
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• pp.315-321
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• 1994

Pleurotus ostreatus로부터 glyoxalase I(S-lactoyl-glutathione methylglyoxal lyase, EC 4.4.1.5)이 S-hexylglutathione affinity chromatography, Sephadex G-150 gel permeation chromatography, DEA-sepharose A-50 CL-6B ion exchange chromatography를 통해 순수 분리되었다. 이 결과, 전체 활성도의 21.7% fmf 수확하였으며, 분리 배수는 2,294 배 이었다. Gel filtration chromatography로 측정한 효소의 분자량은 34 kDa이며, SDS-PAGE 결과 본 효소는 분자량 17 kDa인 동일한 소단위체 두 개로 구성된 이합체라고 생각된다. Methylglyoxal과 phenylglyoxal에 대한 $K_m$ 값은 각각 0.39 mM 과 0.22 mM 이며 L-xylosone과 hydroxypyruvaldehyde에 대해서도 강한 친화력을 보여주었고, pH 6.5~7.5, $35~45^{\circ}C$에서 활성도가 가장 높았다. 이 효소의 반응 과정을 핵자기공 명분광법으로 분석한 결과, 분자내의 양성자 전달과정이 뚜렷이 관찰되었다.

• 대한환경공학회지
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• 제34권6호
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• pp.430-437
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• 2012

홍수터여과에서 집수관의 설계에 대한 자료를 얻기 위해 실험실 규모의 모래통 실험을 수행하였으며, 집수관의 직경, 모래의 투수계수, 집수정의 수위 그리고 지표에서의 원수공급률 등의 변화에 따른 집수관에서의 수두분포와 지하수면 분포를 측정하였다. 측정결과를 수치해석코드에 적용하여 집수관 각 부위에서의 여과수 유입률도 파악하였다. 이들 자료로부터 홍수터여과에서 집수정의 운영수위를 낮춤으로 인한 부작용은 없을 것으로 예상되었으며, 적절한 회수능력에 비해 원수공급률이 큰 경우 대수층에서의 수평방향의 흐름이 발달하여 수평집수관의 통수능 부족을 보완함을 알 수 있었다. 이 경우 여과수의 토양중 이동거리가 늘어나므로 여과수의 수질개선에도 도움이 될 것으로 판단되었고, 따라서 홍수터여과에서는 강변/하상여과에서보다 더 작은 직경의 수평집수관을 사용할 수 있음을 알 수 있었다. 전체 수두손실중 수평집수관에서의 수두손실이 차지하는 비율이 수평집수관 출구유속과 비례함을 알 수 있었으며, 이를 이용하면 홍수터여과에서 수평집수관의 설계와 평가가 가능할 것으로 판단되었다.

• 한국물환경학회지
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• 제24권6호
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• pp.682-689
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• 2008

The purpose of this study was to find out the variation between molecular size distribution (MSD) of natural organic matter (NOM) in raw waters after different water treatment processes like conventional process (coagulation, flocculation, filtration) followed by advanced oxidation process (ozonation, GAC adsorption). The MSD of NOM of Suji pilot plant were determined by Liquid Chromatography-Organic Carbon Detection (LC-OCD) which is a kine of high-performance size-exclusion chromatography (HPSEC) with nondispersive infrared (NDIR) detector and $UV_{254}$ detector. Five distinct fractions were generally separated from water samples with the Toyopearl HW-50S column, using 28 mmol phosphate buffer at pH 6.58 as an eluent. Large and intermediate humic fractions were the most dominant fractions in surface water. High molecular weight (HMW) matter was clearly easier to remove in coagulation and clarification than low molecular weight (LMW) matter. Water treatment processes removed the two largest fractions almost completely shifting the MSD towards smaller molecular size in DW. No more distinct variation of MSD was observed by ozone process after sand filtration but the SUVA value were obviously reduced during increase of the ozone doses. UVD results and HS-Diagram demonstrate that ozone induce not the variation of molecular size of humic substance but change the bond structure from aromatic rings or double bonds to single bond. Granular activated carbon (GAC) filtration removed 8~9% of organic compounds and showed better adsorption property for small MSD than large one.

• Bulletin of the Korean Chemical Society
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• 제4권3호
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• pp.139-143
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• 1983

${\beta}$-N-Acetyl-D-glucosaminidase B was highly purified with the following sequence of steps; DEAE-cellulose, CM-cellulose, and Sephadex G-200 gel filtration chromatograpies. The specific activity of the purified ${\beta}$ -N-acetyl-D-glucosaminidase B was 2.2 units/mg protein with 12.9 % yield and 196.2 fold purity. The purified ${\beta}$-N-acetyl-D-glucosaminidase B showed single band on polyacrylamide gel electrophoresis. The final preparation of ${\beta}$ -N-acetyl-D-glucosaminidase B was completely free friom arylsulfatase and ${\beta}$-glucuronidase. ${\beta}$ -N-Acetyl-D-glucosaminidase B had pH optimum of 4.5 in 0.5 M sodium citrate buffer. The molecular weight of ${\beta}$-N-acetyl-D-glucosaminidase B was 133,000 by Sephadex G-200 gel filtration. The Km value of ${\beta}$-N-acetyl-D-glucosaminidase B using p-nitrophenyl-N-acetyl-${\beta}$-D-glucosaminide as substrate was 1.0 mM and $V_{max}$ was 0.014 ${\mu}$ mole/min. ${\beta}$-N-Acetyl-D-glucosaminidase B was stable at $55^{circ}C$ for 70 minutes. The crude ${\beta}$ -N-acetyl-D-glucosamiinidase in 70 % ammonium sulfate retained 93 % activity after 7 months storage at -$55^{circ}C$. Bovine serum albumin, sodium chloride, and phosphate activated ${\beta}$ -N-Acetyl-D-glucosaminidase B. N-Acetyl-D-glucosamine, ${\alpha}$-methyl-D-mannoside, and acetate inhibited ${\beta}$ -N-acetyl-D-glucosaminidase B.