• 제목/요약/키워드: molecular distribution

검색결과 1,412건 처리시간 0.033초

두류 전분의 분자구조적 특성 (Molecular Structural Properties of Legume Starches)

  • 권미라;안승요
    • 한국식품과학회지
    • /
    • 제25권3호
    • /
    • pp.264-269
    • /
    • 1993
  • 아밀로오스와 아밀로펙틴의 고유점도와 중합도는 강남콩이 다른 시료에 비해 작았다. 겔 크로마토그래피에 의한 분자량 분포의 연구에서는 전분의 경우 강남콩이 대체로 작은 분자들이 많음을 보여주었다. 아밀로오스의 분자량 분포는 특히 강남콩 아밀로오스가 분자량이 작은 것으로 나타났으며 동부와 녹두는 강남콩이나 팥보다 컸고, 팥은 중간이었다. 아울러 아밀로펙틴의 경우 pullulanase로 분해시켰을 때 잘라지는 가지 부분들이 강남콩은 약간 짧았고 동부나 녹두는 강남콩보다는 길었으며 서로 비슷했다. 또한 동부나 녹두는 긴 사슬(DP 40 부근)에 비해 짧은 사슬(DP 15 부근)의 비율이 더 크게 나타났다.

  • PDF

Molecular Modeling of Enantio-discrimination of α-Methoxy-α-trifluoromethylphenylacetic Acid (MTPA) by Cyclomaltoheptaose (β-Cyclodextrin) and 6-Amino-6-deoxy-cyclomaltoheptaose

  • Jung, Eun-Kyoung;Jeong, Karp-Joo;Lee, Sang-San;Kim, Jee-In;Jung, Seun-Ho
    • Bulletin of the Korean Chemical Society
    • /
    • 제24권11호
    • /
    • pp.1627-1631
    • /
    • 2003
  • Molecular modeling was performed to comprehend the chiral recognition of ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid (MTPA) enantiomers by cyclomaltoheptaose (${\beta}$-cyclodextrin,${\beta}$-CD) and 6-amino-6-deoxy-cyclomaltoheptaose (am-${\beta}$-CD). Monte Carlo (MC) docking coupled to constant temperature molecular dynamics (MD) simulations was applied to the investigation for the ${\alpha}$-methoxy-${\alpha}$-trifluoromethylphenylacetic acid complexation with two different CDs in terms of the relative distribution of the interaction energies. The calculated results are finely correlated with the experimental observations in chiral recognition thermodynamics. Am-${\beta}$-CD as a host showed the superior enantio-discrimination ability to the native ${\beta}$-CD where the amino group of am-${\beta}$-CD was critically involved in enhancing the ability of chiral discrimination via the Coulombic interaction with MTPA.

4개의 폴리카프로락톤 가지 코어를 가지는 스타형 폴리카프로락톤의 합성 및 분석 (Synthesis and characterization of Star Shape Polycaprolactone containing 4-Arm Polycaprolactone Core)

  • An, Sung-Guk;Cho, Chang-Gi
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2002년도 봄 학술발표회 논문집
    • /
    • pp.199-202
    • /
    • 2002
  • The synthesis of materials with controlled composition and architectures continues to be a focus of considerable current research. Dendritic multiarm polymers such as dendrimer, hyperbranched polymer, and star polymers are three dimensional macromolecules, in which a large number of linear arms of similar molecular weight and narrow molecular weight distribution emanate from a central core. (omitted)

  • PDF

Preliminary Molecular Dynamics Simulations of the OSS2 Model for the Solvated Proton in Water

  • 이송희
    • Bulletin of the Korean Chemical Society
    • /
    • 제22권8호
    • /
    • pp.847-849
    • /
    • 2001
  • The OSS2(Ojame-Shavitt-Singer 2)[L. Ojame et al., J. Chem. Phys. 109, 5547 (1998)] model as a dissociable water model is examined in order to study the dynamics of H+ in water. MD simulations for 216 water system, 215 water + H+ ion system, and 215 water + OH- ion system using the OSS2 model at 298.15 K with the use of Ewald summation are carried out. The calculated O-H radial distribution functions for these systems are essentially the same and are in very good agreement with that obtained by Ojame.

Leucine Zipper as a Fine Tuner for the DNA Binding; Revisited with Molecular Dynamics Simulation of the Fos-Jun bZIP Complex

  • 최용훈;양철학;김현원;정선호
    • Bulletin of the Korean Chemical Society
    • /
    • 제20권11호
    • /
    • pp.1319-1322
    • /
    • 1999
  • Leucine zipper dynamically tunes the degree of bifurcation of the DNA binding segments in the basic region of the Fos-Jun bZIP complex. Molecular dynamics simulation indicated that site-specific mutagenesis of conserved leucine residues inside the leucine zipper domain caused the change of dynamic behavior of the basic region, and efficient DNA binding occurs only within a certain range of distance between the two DNA binding segments in the basic region. Distribution of α-helices in the hinge region is also suggested to influence the bifurcation of the DNA binding segments.

On-Line Determination of dn/dc for Size Exclusion Chromatography Coupled with a Light Scattering Detector

  • 이희정;장태현
    • Bulletin of the Korean Chemical Society
    • /
    • 제16권7호
    • /
    • pp.640-643
    • /
    • 1995
  • The internal standard method, which is widely used in chromatographic techniques, is applied to the size exclusion chromatography for the on-line determination of dn/dc value of the sample. This method is found to provide the dn/dc value with suitable accuracy in determining the absolute molecular weight and the molecular weight distribution of the polymers when a light scattering detector is used.

Kinetic Energy Release in the Fragmentation of tert-Butylbenzene Molecular Ions. A Mass-analyzed Ion Kinetic Energy Spectrometric (MIKES) Study

  • Choe, Joong-Chul;Kim, Byung-Joo;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
    • /
    • 제10권2호
    • /
    • pp.167-171
    • /
    • 1989
  • Kinetic energy release in the fragmentation of tert-butylbenzene molecular ion was investigated using mass-analyzed ion kinetic energy spectrometry. Method to estimate kinetic energy release distribution (KERD) from experimental peak shape has been explained. Experimental KERD was in good agreement with the calculated result using phase space theory. Effect of dynamical constraint was found to be important.

Distribution of Pathogenic Genes and Molecular Typing of Yersinia pseudotuberculosis isolated from Spring Water in Seoul

  • Kim, Mi-Sun;Shim, Mi-Ja
    • 대한약학회:학술대회논문집
    • /
    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
    • /
    • pp.161.2-161.2
    • /
    • 2003
  • In order to investigate the pathogenic genes and genetic relationships of Y. pseudotuberculosis, we isolated 9 strains of Y. pseudotuberculosis from about 380 spring water sites in Seoul and carried out antibiotic susceptibility test, biological test and molecular typing. All isolated strains were distributed throughout the northeast area in Seoul (Mt. Bookhan, Mt. Soorak, Mt. Boolam and etc...).Antibiotic susceptibility test revealed that all the strains were susceptible to chloramphenicol, gentamicin, neomycin and amoxicillin/clavulanic acid, but were resistant to novobiocin and vancomycin. (omitted)

  • PDF