• 제목/요약/키워드: and nitrile

검색결과 168건 처리시간 0.027초

Hydrolysis of the Nitrile group in $\alpha$-Aminophenylacetonitrile by Nitrilase;Development of a New Biotechnology for Stereospecific Production of S-$\alpha$-Phenylglycine

  • Choi, Soo-Young;Goo, Yang-M
    • Archives of Pharmacal Research
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    • 제9권1호
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    • pp.45-47
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    • 1986
  • Phenylglycine was obtained as the sole metabolite when .alpha.-aminophenylacetonitrile was ted to the culture broth of Aspergillus furmigatus furmigatus. The isolated phenylglycine showed L-configuration with 80% optical purity. Examination of the hydrolysis of the substrate to phenylglycine with cell free extracts, and the supernatant fraction and the particulate fraction both of which were obtained after ultracentrifugation of the cell free extract at 100,000g, indicated that the nitrile group hydrolyzing enzymes, nitrilase existed not only in cytoplasm, but in microsome fractions.

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Cure Mechanism of DGEBA/MDA/SN System

  • 심미자;김성욱
    • 한국재료학회지
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    • 제3권3호
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    • pp.272-275
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    • 1993
  • To modify the toughness of epoxy for matrix, succinonitrile(SN) was introduced to diglycidy1 ether of bisphenol-A (DGEBA)/methylene dianiline(MDA)system. Cure reaction mdchanism of the DGEBA/MDA/SN system was strdied through Fourier transform infrared(FT-IR) spectrometry. As a result, the reaction of nitrile group of SN with secondary amine and with hydroxy1 group prevented the reaction of hydroxy1 group with epoxide group from crossoinding. Nitrile groups produced amide group by reacting with hydroxy1 groups and made a lowered crosslind density in chain networks.

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브로콜리 용매추출물의 Bioactive Organosulfur 화합물의 분리 및 동정 (Isolation and Identification of Bioactive Organosulfur Phytochemicals from Solvent Extract of Broccoli)

  • 석대은;김진희;김미리
    • 한국식품영양과학회지
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    • 제32권3호
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    • pp.315-319
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    • 2003
  • 브로콜리 중의 bioactive organosulfur phytochemicals를 분석하기 위해 브로콜리를 용매추출하여 GC/MSD에 의해 분리동정하였다. 브로콜리에 함유된 phytochemicals 중에서 isothiocyanate류가 40.42%로 대부분을 차지하였으며, glucosinolate분해산물인 nitrile류는 5.12%로 isothiocyanate류에 비해 적었고, sulfide류는 0.84%로 매우 적었다. 분리 동정된 isothiocyanate류의 종류로는 3-butenyl 4-methtlthiobutyl, 4-methrlthio -3- butenyl, 5- methylthiopentyl, 2- phenylethyl, 3-methylsulfinyl propyl 및 4-methylsulfinylbutyl isothiocyanate의 7종이었다. Isothiocyanate류 중에서 3-butenyl isothiocynate는 22.05%로 가장 많았으며, 그 다음으로 sulforaphane 16.50%로 2종의 isothiocyanate가 대부분을 차지하였다. Nitrile의 종류는 4-methylthiobutyl, 5-methylthiopentyl, 2-phenylethyl 및 4-methylsulfinylbutyl nitrile의 6종류가 확인되었다. 한편, 동정된 sulfide종류로는 dimethyl disulfide, dimethyl trisulfide 및 dimethyl tetrasulfide이었다.

Application of Response Surface Methodology and Plackett Burman Design assisted with Support Vector Machine for the Optimization of Nitrilase Production by Bacillus subtilis AGAB-2

  • Ashish Bhatt;Darshankumar Prajapati;Akshaya Gupte
    • 한국미생물·생명공학회지
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    • 제51권1호
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    • pp.69-82
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    • 2023
  • Nitrilases are a hydrolase group of enzymes that catalyzes nitrile compounds and produce industrially important organic acids. The current objective is to optimize nitrilase production using statistical methods assisted with artificial intelligence (AI) tool from novel nitrile degrading isolate. A nitrile hydrolyzing bacteria Bacillus subtilis AGAB-2 (GenBank Ascension number- MW857547) was isolated from industrial effluent waste through an enrichment culture technique. The culture conditions were optimized by creating an orthogonal design with 7 variables to investigate the effect of the significant factors on nitrilase activity. On the basis of obtained data, an AI-driven support vector machine was used for the fitted regression, which yielded new sets of predicted responses with zero mean error and reduced root mean square error. The results of the above global optimization were regarded as the theoretical optimal function conditions. Nitrilase activity of 9832 ± 15.3 U/ml was obtained under optimized conditions, which is a 5.3-fold increase in compared to unoptimized (1822 ± 18.42 U/ml). The statistical optimization method involving Plackett Burman Design and Response surface methodology in combination with an AI tool created a better response prediction model with a significant improvement in enzyme production.

현탁중합으로 합성된 구형 PAN 수지의 구형 활성탄의 전구체로서의 활용 (Application of Suspension-Polymerized Spherical PAN beads as a Precursor of Spherical Activated Carbon)

  • 염혜원;김홍경
    • 융복합기술연구소 논문집
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    • 제12권1호
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    • pp.13-18
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    • 2022
  • Polyacrylonitrile was synthesized through suspension polymerization and then sieved to obtain spherical beads with a size of 200~510 ㎛. PAN was copolymerized with 2 mol% MMA monomer which is known to promote cyclization and crosslinking of nitrile group. The resonance cyclization reaction of the nitrile group in the synthesized PAN beads was observed near 170℃ with thermal analysis and FT-IR. The reaction conversion of the nitrile group in spherical beads was 23% during heat treatment, which was lower than that of the well-oriented PAN fiber used as a precursor of carbon fiber. This is because the stereo-regularity of molecular chains in the form of a random coil (spherical bead) is much lower than that of PAN fiber. It was confirmed that the compressive strength of the spherical PAN bead was greatly improved through the resonance cyclization and shrinkage according to the heat treatment, and it was also observed that the pores in PAN beads were formed after the heat treatment.

카본 함량에 따른 니트릴 부타디엔 고무의 음향 특성 (Acoustic Characteristics of Nitrile Butadiene Rubber with Carbon Black Content)

  • 정경일;윤석왕;조국영;박정기
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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    • pp.377-380
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    • 2002
  • Acoustic Characteristics of Nitrile Butadiene Rubber with Carbon Black ContentAcoustic and mechanical properties of Nitrile Butadiene Rubbers (NBR) with the variation of the carbon black content were investigated. NBR where the acrylonitrile content is $33\%$ based on the mole percent has been prepared with fixed sulfur content for vulcanization. Acoustic measurement of the prepared rubbers were peformed in the frequency region of $300\;\~\;1000\;kHz$. Their mechanical properties such as density, hardness were also measured. Increase of the carbon black content in the rubber resulted in enhancement of the mechanical property and linear increase of the sound speed as function of the carbon black content. Interestingly, attenuation of the sound speed was only affected by the existence of the carbon black and not by the amount of carbon black in the experiment range of this article. In this study, it was found that the amount of carbon black content in the NBR was correlated with the acoustic properties and can be estimated nondestructively by the measurement of the specific acoustic property.

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아크릴로니트릴이 극성기로 도입된 유화중합 SBR/실리카 컴파운드의 기계적 물성 (Mechanical Properties of Acrylonitrile Functionalized Emulsion SBR/silica Compounds)

  • 김동원;서병호;김희정;백현종;강종원;김원호
    • Elastomers and Composites
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    • 제47권1호
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    • pp.54-64
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    • 2012
  • 본 연구에서는 polar 한 silica 와 non-polar 한 고무사이의 친화력을 증대시키기 위하여 SBR 분자 주쇄에 acrylonitrile 을 도입시킨 acrylonitirle functionalized emulsion SBR 의 물성에 관하여 연구하였다. Acrylonitrile의 nitrile group 은 silica 표면의 silanol group 과 H-bond 를 형성할 수 있음으로 polar 한 silica 표면에 흡착되는 가교촉진제를 줄이고 가황반응을 촉진시키는 것으로 판단된다. SBR 및 AN-SBR 에 PEG 를 적용한 컴파운드의 경우 PEG 와 silica 표면의 silanol group 과의 상용성이 높아 가교촉진제가 polar 한 silica 표면에 흡착됨을 줄여 가교시간이 단축된 것으로 판단된다. 기계적 물성에서 AN-SBR 컴파운드는 SBR 1721 컴파운드 대비 100%, 300%에서 높은 모듈러스 값을 나타내었다. 이러한 결과는 AN-SBR 의 높은 분자량 및 nitrile group 의 도입에 따른 가교도의 상승에 의한 결과로 판단된다. 동적점탄특성 결과에서 AN-SBR 컴파운드는 SBR 1721 컴파운드 대비 $60^{\circ}C$ 에서 낮은 tan ${\delta}$ 값을 나타내었으며, 이는 nitrile group 과 silica 사이의 친화력에 따른 filler-rubber interaction의 향상에 의해 반복변형에 의한 energy dissipation 이 낮은 것으로 판단된다.

근권에서 분리한 세균의 IAA 생합성 경로와 IAA 생성능과의 관계 (Interactions between Biosynthetic Pathway and Productivity of IAA in Some Rhizobacteria)

  • 김운진;송홍규
    • 미생물학회지
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    • 제48권1호
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    • pp.1-7
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    • 2012
  • 대표적인 식물호르몬인 indole-acetic acid (IAA)를 생성하는 근권세균에서 IAA 생합성 경로와 생성량과의 관계를 파악하기 위해 IAA 생성능이 크게 다른 4개 균주를 선발하고 동정하였다. 특정 경로를 이용한 IAA 생합성능의 조사를 위해 주요 전구물질을 첨가하여 IAA 생성량을 측정하였다. Tryptophan 의존적 경로에 의한 총 IAA 생성량은 Acinetobacter guillouiae SW5가 1.66 mg/ml로 가장 높았으며, indole acetamide (IAM)를 배지에 첨가했을 때 amidase의 활성은 분리균주 중 Rhodococcus equi SW9이 가장 높았다. IAA 생합성을 위한 또 다른 두 가지 경로의 전구물질인 indole acetonitrile (IAN)을 첨가하였을 때 IAA 생합성은 A. guillouiae SW5가 가장 높았으며, 이 때 nitrilase 보다는 nitrile hydratase의 활성이 높았다. 그러나 두 경로 중 IAN을 직접 IAA로 전환시키는 nitrilase의 활성은 Bacillus thuringiensis SW17이 균주들 중 가장 높았다. B. thuringiensis SW17은 4균주 중 IAA생합성능이 가장 낮았으며 tryptophan을 이용하여 생합성하는 IAA 중 상당량을 IAM을 거치는 경로를 통해 생성한다. Lysinibacillus fusiformis SW13은 IAA 생합성에 관여하는 nitrile 전환경로들을 비교적 고르게 이용하여 IAA를 생성하였다. Tryptophan 비의존적 경로를 통한 IAA 생합성은 A. guillouiae SW5에서만 소량 관찰되었다.