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Oxidative Dehydrogenation of 1-butene over BiFe0.65MoP0.1 Catalyst: Effect of Phosphorous Precursors (BiFe0.65MoP0.1 촉매 상에서 1-부텐의 산화탈수소화 반응 : 인 전구체의 영향)

  • Park, Jung-Hyun;Youn, Hyun Ki;Shin, Chae-Ho
    • Korean Chemical Engineering Research
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    • v.53 no.6
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    • pp.824-830
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    • 2015
  • The influence of phosphorous precursors, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$, $H_3PO_4$, $(C_2H_5)_3PO_4$, and $P_2O_5$, on the catalytic performance of the $BiFe_{0.65}MoP_{0.1}$ catalysts in the oxidative dehydrogenation of 1-butene to 1,3-butadiene was studied. The catalysts were characterized by XRD, $N_2$-sorption, ICP, SEM and TPRO analyses. It was not observed big difference on the physical properties of catalysts in accordance with used different phosphorous precursors, however, the catalytic performance was largely depended on the nature of the phosphorous precursors. Of various precursors, the $BiFe_{0.65}MoP_{0.1}$ oxide catalyst, which was prepared from a phosphoric acid precursor, showed the best catalytic performance. Conversion and yield to butadiene of the catalyst showed 79.5% and 67.7%, respectively, after 14 h on stream. The cation of phosphorous precursors was speculated to affect the lattice structure of the catalysts during catalyst preparation and this difference was influenced on the re-oxidation ability of the catalysts. Based on the results of TPRO, it was proposed that the catalytic performance could be correlated with re-oxidation ability of the catalysts.

Optimization of Glycosyl Aesculin Synthesis by Thermotoga neapolitana β-Glucosidase Using Response-surface Methodology (반응표면분석법을 이용한 Thermotoga neapolitana β-glucosidase의 당전이 활성을 통한 glycosyl aesculin 합성 최적화)

  • Park, Hyunsu;Park, Young-Don;Cha, Jaeho
    • Journal of Life Science
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    • v.27 no.1
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    • pp.38-43
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    • 2017
  • Glycosyl aesculin, a potent anti-inflammatory agent, was synthesized by transglycosylation reaction, catalyzed by Thermotoga neapolitana ${\beta}-glucosidase$, with aesculin as an acceptor. The key reaction parameters were optimized using response-surface methodology (RSM) and $2{\mu}g$ of the enzyme. As shown by a statistical analysis, a second-order polynomial model fitted well to the data (p<0.05). The response surface curve for the interaction between aesculin and other parameters revealed that the aesculin concentration and reaction time were the primary factors that affected the yield of glycosyl aesculin. Among the tested factors, the optimum values for glycosyl aesculin production were as follows: aesculin concentration of 9.5 g/l, temperature of $84^{\circ}C$, reaction time of 81 min, and pH of 8.2. Under these conditions, 61.7% of glycosyl aesculin was obtained, with a predicted yield of 5.86 g/l. The maximum amount of glycosyl aesculin was 6.02 g/l. Good agreement between the predicted and experimental results confirmed the validity of the RSM. The optimization of reaction conditions by RSM resulted in a 1.6-fold increase in the production of glycosyl aesculin as compared to the yield before optimization. These results indicate that RSM can be effectively used for process optimization in the synthesis of a variety of biologically active glycosides using bacterial glycosidases.

Development of Lipase Hyper-producing Strain from Hybrids between Aspergillus niger and Penicillium notatum by Nuclear Transfer (핵전이에 의한 Aspergillus niger와 Penicillium notatum 잡종에서의 lipase 고생산 균주의 개발)

  • Yang, Young-Ki;Moon, Myeng-Nim;Lee, Yoon-Hee;Kang, Hee-Kyoung;Lee, Jung-Sup;Lim, Chae-Young;Kim, Jong-Se;Rhee, Young-Ha
    • The Korean Journal of Mycology
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    • v.25 no.2 s.81
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    • pp.143-151
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    • 1997
  • Interspecific hybrids between Aspergillus niger and Penicillium notatum (Tyr-), hyperlipolytic enzyme-producing fungi, were obtained by nuclear transfer technique. Optimal conditions for formation of intergeneric hybrids were investigated. Maximum production of protoplasts was obtained by 1% Novozyme 234 at $30^{\circ}C$ for 3 hrs and the most effective osmotic stabilizers for the isolation of protoplasts were 0.6 M KCl. Frequencies of hybrid formation by nuclear transfer were $3.8{\times}10^{-3}{\sim}1.3{\times}10^{-3}$. From the observation of genetic stability, conidial size, DNA content, and nuclear stain, it was suggested that their karyotypes are aneuploid. The hybrids showed $1.2{\sim}1.7$ fold higher lipase activities than parental strains. It was strongly supported by results of this study that nuclear transfer technique is much more efficient in the formation of intergeneric hybrids than protoplast fusion and is very useful for the improvement of strains.

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A Study on the Fertilizing Effect of Swine Fermentation Liquid Manures under the Hydroponics (양돈분뇨의 양액재배용 비효 연구)

  • Lee Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.10 no.3
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    • pp.169-174
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    • 2004
  • The present study investigated the possibility of applying the fermented swine liquid manure handled with TAO system to hydroponic cultivation. The fermented swine liquid manure (FLM) used for the study was in low concentration of phosphoric acid (P). Hence, when doing hydroponic cultivation, the concentration of P and K was supplemented. The concentrations of N, P, and K in compensated FLMs were as fellows; (a) N 58mg/1, P 0.5mg/1 and K 31 mg/1 for FLM-1, (b) N 58mg/1, P 31 mg/l and K 39mg/1 for FLM-2, and (c) N 58mg/1, P 31 mg/1 and K 61 mg/1 for FLM-3, respectively. For hydroponic cultivation, it was possible to use diluted solution by 100 times through experiment of germination index. According to the experiment using lettuce, the compensated FLMs with P and K were superior in leaf width, yield and dry weight to FLM without any treatment. Therefore, it is necessary to supplement some nutrition before applying. In conclusion, it is highly estimated that the fermented swine liquid manure can be ap-plied to hydroponic cultivation. It is also necessary to conduct further researches related to nutritional compensation depending on the vegetables.

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Introduction and Expression of PAP gene using Agrobacterium in Scrophularia buergeriana Miquel (Agrobacterium을 이용한 PAP 유전자의 현삼으로 도입 및 형질발현)

  • Yu, Chang-Yeon;Seong, Eun-Soo;Lim, Jung-Dae;Huang, Shan-Ai;Chae, Young-Am
    • Korean Journal of Medicinal Crop Science
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    • v.9 no.2
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    • pp.156-165
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    • 2001
  • Exogeneous application of pokeweed antiviral protein (PAP), a ribosomal-inacivating protein in the cell wall of Phytolacca americana (pokeweed) protects heterologous plants from viral and fungal infection. A cDNA clone of PAP introduced into Scrophularia buergeriana Miquel by thransformation with Agrobacterium tumefaciences. For plant transformation, explants were precultured on shoot induction medium without kanamycin for 2-5 day, and then they were cocultured with Agrobacterium for 10 minutes. The explants were placed on co culture medium in dark condition, $28^{\circ}C$ for 2days. After explants were washed in MS liquid medium, they were transferred into selection medium including kanamycin 50mg/L (MS salts+1mg/ l BAP+2mg/ l TDZ+0,2mg/ l NAA+MS vitamin+3% sucrose+0.8% agar, pH5.8). From PCR analysis, NPT II band was confirmed in transgenic plant genome and showed resistance against fungi in antifungal activity test. Micro assay to which protein extracted from transgenic line were added, revealed hyphae growth inhibition and no spore germination at high concentration. The characteristics of inhibited hyphae was represented transparent and thin. Expression of PAP in transgenic plants offers the possibility of developing resistance to viral and fungal infection.

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Angiotensin Converting Enzyme Inhibitory Activity in Peptic Hydrolysates of Cooking Discards from Anchovy Factory Ship (멸치 가공선 자숙폐액 Pepsin 가수분해물의 Angiotensin 전환효소 저해작용)

  • Ji, Cheong-Il;Lee, Ji-Hye;Park, Douck-Choun;Gu, Yeun-Suk;Kim, In-Soo;Lee, Tae-Gee;Jung, Kyoo-Jin;Park, Yeung-Ho;Kim, Seon-Bong
    • Korean Journal of Food Science and Technology
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    • v.34 no.3
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    • pp.529-532
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    • 2002
  • The angiotensin converting enzyme (ACE) inhibitory activity in peptic hydrolysate of raw anchovy cooking discards was 51.3% at 1 mg of protein per $100\;{\mu}L$ sample solution. While, after the treatment of pepsin for 4 h, was 65.8%. The crude peptides fractionated through Bio-gel P-2 column chromatography consisted of five fractions $({P-1}{\sim}{P-5})$ and had maximum inhibitory activity in the fraction P-2 ($IC_{50}$=0.319 mg protein/mL). The fraction P-2 was rich in aspartic acid, glutamic acid, and glycine.

Physiological Studies on the Formation of Hairy Root by the Agrobacterium rhizogenes ; IV. Culture of Hairy Root and Survey of the Culture Condition. (Agrobacterium rhizogenes 에 의한 hairy root 형성에 대한 생리학적 연구 ; IV. Hairy root 배양 및 배양 조건에 관한 조사)

  • Hwang, Baik;An, Jun-Cheul;lee, Jae-Hyuk
    • KSBB Journal
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    • v.4 no.3
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    • pp.246-253
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    • 1989
  • Hairy roots of carrot were induced by Agrobacterium rhizogenes $A_4$ strain within about 2-4 weeks after inoculated from root disc. Early axonic culture is established in RCM agar medium and following is in MS rigid medium. After 15 days culture, the hairy roots were vigrous growth in about 10 times of initial inoculum. Anthocyanin contents of hairy roots were more than of ordinary roots. 2, 4-D ($10^{-4}mg/ l$), sucrose (5%), nitrogen source (0.03M) contained medium was optimized to growth of hairy root and contents of anthocyanin. Phenotypic alterations of leaves are observed in transformed plants and determined the transformation of hairy roots and the transformed plants by opine assay.

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Development of Transgenic NT Embryos Using Bovine Fetal Fibroblasts Transfected with hFSH Gene (hFSH 유전자가 도입된 소 태아섬유아세포를 이용한 형질 전환 복제 수정란의 발달)

  • Yang B.C.;Im G.S.;Kim D.H.;Min K.S.;Yoon D.H.;Park H.S.;Kim S.W.;Hwang I.S.;Seo J.S.;Seong H.H.;Yang B.S.
    • Journal of Embryo Transfer
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    • v.21 no.1
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    • pp.13-20
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    • 2006
  • The purpose of this study was to develope the transgenic cattle expressing hFSH into the urine using the nuclear transfer. To produce the interest gene in urine, the specific vector was ligated with hFSH gene undo. maUII promoter. The fetal fibroblast cells (KbFF) were isolated from a 45-day male fetus. The hFSH gene was co-transfected with pcDNA3 (neo) vector to KbFF cells by electroporation. The gene-transfected cells were cultured with G-418 selection medium for 2 weeks. Selected colonies were confirmed by PCR. For nuclear transfer, enucleated bovine oocytes were transferred with hFSH transfected or nontransfected fetal fibroblasts. The cleavage and blastocyst formation rates were significantly lower (p<0.05) in cloned embryos transfected with hFSH gene (68.7% and 15.7%) than in those non-transfected (67.6% and 24.5 %), respectively. Apoptosis analysis showed no difference between hFSH transfected and non-transfected blastocysts (p>0.05). The blastocysts were transfected to 77 (control 24, hFSH 53) recipient cows. Two calves were born (1.9%) following transfer with NT embryos transfected with hFSH gene, but they were confirmed not to be transgenic calves. This result shows that the hFSH colonies were mixed with transfected and non transfected cells. Further research will be needed for selection and establishment of gene transfected cells.

Thermostable $\alpha$-Amylase Production by Thermophilic Bacillus sp. TR-25 lsolated from Extreme Enviroment (극한환경에서 분리한 고온성 Bacillus sp. TR-25에 위한 내열성 $\alpha$-amylase의 생산)

  • 노석범;손홍주;이종근
    • Journal of Life Science
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    • v.7 no.1
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    • pp.30-38
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    • 1997
  • For screening thermostable $\alpha$-amylase from thermophiles, various samples from extreme environments such as hot spring and sewage near them, and compoat, wereexamined microbial growth in enrichment culture medium at 55$\circ$C on the assumption that enzymes from thermophiles are inevitable thermostable. One strain showing higher $\alpha$-amylase activity was pure cultured and designated as Bacillus sp. TR-25 from the results of morphological, cultural and physiological characteristics. The most important carbon sourses for the enzyme production were soluble starch, dextrin, potato starch and corn starch. Glucose and fructose had a catabolite repression on the enzyme production. The good nitrogen sources for the enzyme production were yeat extract, nutrient broth, tryptone, corn steep liquor and ammonium sulfate. The enzyme production was accelerated by addition of CaCl$_{2}$. $\cdot $ H$_{2}$O. The optimal medium composition for the enzyme production was soluble starch 2.0%, yeast extract 0.55, CaCl$_{2}$ $\cdot $ 2H$_{2}$O 0.015, Tween 80 0.001%, pH8.0, respectively. In jar fermenter culture, this strain shows a rapid growth and required cheaper carbon and nitrogen source. These properties are very useful to fermentation industry. The $\alpha$-amylase of this strain demonstrated a maximum activity at 80$\circ$C, pH 5.0, respectively. And calcium ion did not improve thermostability of the enzyme. At 10$0^{\circ}C$, this enzyme has 235 of relative activity. Transformation was carried out by thermophilic Bacillus sp. TR-25 genomic DNA. As a result, the transformant has increased thermostable $\alpha$-amylase activity.

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A Study on the Regeneration Effects of Commercial $V_2O_5-WO_3/TiO_2$ SCR Catalyst for the Reduction of NOx (질소산화물 제거용 상용 $V_2O_5-WO_3/TiO_2$ SCR 폐 촉매의 재생 효과 고찰)

  • Park, Hea-Kyung
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.8
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    • pp.859-869
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    • 2005
  • The commercial $V_2O_5-WO_3/TiO_2$ catalysts which had been exposed to the off gas from incinerator for a long time were regenerated by physical and chemical treatment. The catalytic properties and NOx conversion reactivity of those catalysts were examined by analysis equipment and NOx conversion experiment. The characterization of the catalysts were performed by XRD(x-ray diffractometer), BET, POROSIMETER, EDX(energy dispersive x-ray spectrometer), ICP(inductively coupled plasma), TGA(thermogravimetric analyzer) and SEM (scanning electron microscopy). NOx conversion experiment were performed with simulated off gas of the incinerator and $NH_3$ was used as a reductant of SCR reaction. Among the regeneration treatment methods which were applied to regenerate the aged catalysts in this study, it showed that the heat treatment method had excellent regeneration effect on the catalytic performance for NOx conversion. The catalytic performance of the regenerated catalysts with heat treatment method were recovered over than 95% of that of fresh catalyst. For the regenerated catalysts with the acid solution(pH 5) and the alkali solution(pH 12), the catalytic performance were recovered over than 90% of that of fresh catalyst. From the characterization results of the regenerated catalysts, the specific surface area was recovered in the range of $85{\sim}95%$ of that of fresh catalyst. S and Ca element, which are well known as the deactivation materials for the SCR catalysts, accumulated on the aged catalyst surface were removed up to maximum 99%. Among the P, Cr, Zn and Pb elements accumulated on the aged catalyst surface, P, Cr and Zn element were removed up to 95%. But the Pb element were removed in the range of $10{\sim}30%$ of that of fresh catalyst.