메뉴 건너뛰기




Volumn 168, Issue 2, 2007, Pages 243-252

Theoretical investigation of the formation of a new series of antioxidant depsides from the radiolysis of flavonoid compounds

Author keywords

[No Author keywords available]

Indexed keywords

ALCOHOL; APIGENIN; CATECHIN; CHRYSIN; DEPSIDE; ERIODYCTIOL; ETHOXY DEPSIDE; FLAVONOID; FLAVONOL DERIVATIVE; GALAGIN; HYDROXYL GROUP; KAEMPFEROL; LUTEOLIN; METHOXY DEPSIDE; MORIN; NARINGENIN; PEROXY RADICAL; QUERCETIN; TAXIFOLIN; UNCLASSIFIED DRUG; ANTIOXIDANT; FREE RADICAL; METHANOL; OXYGEN;

EID: 34548448877     PISSN: 00337587     EISSN: None     Source Type: Journal    
DOI: 10.1667/RR0824.1     Document Type: Article
Times cited : (40)

References (55)
  • 2
    • 0027504187 scopus 로고
    • Dietary antioxidant flavonoids and risk of coronary heart disease: The Zutphen Elderly Study
    • M. G. Hertog, E. J. Feskens, P. C. Hollman, M. B. Katan and D. Kromhout, Dietary antioxidant flavonoids and risk of coronary heart disease: The Zutphen Elderly Study. Lancet 342, 1007-1011 (1993).
    • (1993) Lancet , vol.342 , pp. 1007-1011
    • Hertog, M.G.1    Feskens, E.J.2    Hollman, P.C.3    Katan, M.B.4    Kromhout, D.5
  • 3
    • 0029888128 scopus 로고    scopus 로고
    • Structure-antioxidant activity relationships of flavonoids and phenolic acids
    • C. A. Rice-Evans, N. J. Miller and G. Paganga, Structure-antioxidant activity relationships of flavonoids and phenolic acids. Free Radic. Biol. Med. 20, 933-956 (1996).
    • (1996) Free Radic. Biol. Med , vol.20 , pp. 933-956
    • Rice-Evans, C.A.1    Miller, N.J.2    Paganga, G.3
  • 4
    • 0031886669 scopus 로고    scopus 로고
    • Structure-activity relationship and classification of flavonoids as inhibitors of xanthine oxidase and superoxide scavengers
    • P. Cos, L. Ying, M. Calomme, J. P. Hu, K. Cimanga and B. Van Poel, Structure-activity relationship and classification of flavonoids as inhibitors of xanthine oxidase and superoxide scavengers. J. Nat. Prod. 61, 71-76 (1998).
    • (1998) J. Nat. Prod , vol.61 , pp. 71-76
    • Cos, P.1    Ying, L.2    Calomme, M.3    Hu, J.P.4    Cimanga, K.5    Van Poel, B.6
  • 7
    • 0037316930 scopus 로고    scopus 로고
    • Redox reactions obtained by gamma irradiation of quercetin methanol solution are similar to in vivo metabolism
    • A. Marfak, P. Trouillas, D. P. Allais, C. A. Calliste and J. L. Duroux, Redox reactions obtained by gamma irradiation of quercetin methanol solution are similar to in vivo metabolism. Radiat. Res. 159, 218-227 (2003).
    • (2003) Radiat. Res , vol.159 , pp. 218-227
    • Marfak, A.1    Trouillas, P.2    Allais, D.P.3    Calliste, C.A.4    Duroux, J.L.5
  • 8
    • 0037467137 scopus 로고    scopus 로고
    • Radiolysis of kaempferol in water/methanol mixtures. Evaluation of antioxidant activity of kaempferol and products formed
    • A. Marfak, P. Trouillas, D. P. Allais, Y. Champavier, C. A. Calliste and J. L. Duroux, Radiolysis of kaempferol in water/methanol mixtures. Evaluation of antioxidant activity of kaempferol and products formed. J. Agric. Food Chem. 51, 1270-1277 (2003).
    • (2003) J. Agric. Food Chem , vol.51 , pp. 1270-1277
    • Marfak, A.1    Trouillas, P.2    Allais, D.P.3    Champavier, Y.4    Calliste, C.A.5    Duroux, J.L.6
  • 9
    • 0041317714 scopus 로고    scopus 로고
    • Mechanisms of transformation of the antioxidant kaempferol into depsides. Gamma-radiolysis study in methanol and ethanol
    • A. Marfak, P. Trouillas, D. P. Allais, Y. Champavier, C. A. Calliste, J. Cook-Moreau and J. L. Duroux, Mechanisms of transformation of the antioxidant kaempferol into depsides. Gamma-radiolysis study in methanol and ethanol. Radiat. Res. 160, 355-365 (2003).
    • (2003) Radiat. Res , vol.160 , pp. 355-365
    • Marfak, A.1    Trouillas, P.2    Allais, D.P.3    Champavier, Y.4    Calliste, C.A.5    Cook-Moreau, J.6    Duroux, J.L.7
  • 11
    • 0035857407 scopus 로고    scopus 로고
    • Predicting the activity of phenolic antioxidants: Theoretical method, analysis of substituent effects, and application to major families of antioxidants
    • J. S. Wright, E. R. Johnson and G. A. DiLabio, Predicting the activity of phenolic antioxidants: Theoretical method, analysis of substituent effects, and application to major families of antioxidants. J. Am. Chem. Soc. 123, 1173-1183 (2001).
    • (2001) J. Am. Chem. Soc , vol.123 , pp. 1173-1183
    • Wright, J.S.1    Johnson, E.R.2    DiLabio, G.A.3
  • 12
    • 9644295549 scopus 로고    scopus 로고
    • On the effectiveness of the EPR radical equilibration technique in estimating O-H bond dissociation enthalpies of catechols and other complex polyphenols
    • H. Y. Zhang, On the effectiveness of the EPR radical equilibration technique in estimating O-H bond dissociation enthalpies of catechols and other complex polyphenols. New J. Chem. 28, 1284-1285 (2004).
    • (2004) New J. Chem , vol.28 , pp. 1284-1285
    • Zhang, H.Y.1
  • 13
    • 1642502300 scopus 로고    scopus 로고
    • Structure, conformation, and electronic properties of apigenin, luteolin, and taxifolin antioxidants. A first principle theoretical study
    • M. Leopoldini, I. P. Pitarch, N. Russo and M. Toscano, Structure, conformation, and electronic properties of apigenin, luteolin, and taxifolin antioxidants. A first principle theoretical study. J. Phys. Chem. A 108, 92-96 (2004).
    • (2004) J. Phys. Chem. A , vol.108 , pp. 92-96
    • Leopoldini, M.1    Pitarch, I.P.2    Russo, N.3    Toscano, M.4
  • 14
    • 0033860031 scopus 로고    scopus 로고
    • Semiempirical molecular modeling into quercetin reactive site: Structural, conformational, and electronic features
    • N. Russo, M. Toscano and N. Uccella, Semiempirical molecular modeling into quercetin reactive site: structural, conformational, and electronic features. J. Agric. Food Chem. 48, 3232-3237 (2000).
    • (2000) J. Agric. Food Chem , vol.48 , pp. 3232-3237
    • Russo, N.1    Toscano, M.2    Uccella, N.3
  • 15
    • 0035913305 scopus 로고    scopus 로고
    • Structural and spectroscopic investigation of 5-hydroxyflavone and its complex with aluminium
    • J. P. Cornard and J. C. Merlin, Structural and spectroscopic investigation of 5-hydroxyflavone and its complex with aluminium. J. Mol. Struct. 569, 129-138 (2001).
    • (2001) J. Mol. Struct , vol.569 , pp. 129-138
    • Cornard, J.P.1    Merlin, J.C.2
  • 16
    • 0037201690 scopus 로고    scopus 로고
    • Spectroscopic and structural study of complexes of quercetin with A1(III)
    • J. P. Cornard and J. C. Merlin, Spectroscopic and structural study of complexes of quercetin with A1(III). J. Inorg. Biochem. 92, 19-27 (2002).
    • (2002) J. Inorg. Biochem , vol.92 , pp. 19-27
    • Cornard, J.P.1    Merlin, J.C.2
  • 17
    • 0038408767 scopus 로고    scopus 로고
    • Comparison of the chelating power of hydroxyflavones
    • J. P. Cornard and J. C. Merlin, Comparison of the chelating power of hydroxyflavones. J. Mol. Struct. 651-653, 381-387 (2003).
    • (2003) J. Mol. Struct , vol.651-653 , pp. 381-387
    • Cornard, J.P.1    Merlin, J.C.2
  • 18
    • 3242723376 scopus 로고    scopus 로고
    • A theoretical study of the conformational behavior and electronic structure of taxifolin correlated with the free radical-scavenging activity
    • P. Trouillas, C. Fagnère, R. Lazzaroni, C. A. Calliste, A. Marfak and J. L. Duroux, A theoretical study of the conformational behavior and electronic structure of taxifolin correlated with the free radical-scavenging activity. Food Chem. 88, 571-582 (2004).
    • (2004) Food Chem , vol.88 , pp. 571-582
    • Trouillas, P.1    Fagnère, C.2    Lazzaroni, R.3    Calliste, C.A.4    Marfak, A.5    Duroux, J.L.6
  • 19
    • 31844444029 scopus 로고    scopus 로고
    • A DFT study of the reactivity of OH groups in quercetin and taxifolin antioxidants: The specificity of the 3-OH site
    • P. Trouillas, P. Marsal, D. Siri, R. Lazzaroni and J. L. Duroux, A DFT study of the reactivity of OH groups in quercetin and taxifolin antioxidants: The specificity of the 3-OH site. Food Chem. 97, 679-688 (2006).
    • (2006) Food Chem , vol.97 , pp. 679-688
    • Trouillas, P.1    Marsal, P.2    Siri, D.3    Lazzaroni, R.4    Duroux, J.L.5
  • 20
    • 2442417429 scopus 로고    scopus 로고
    • Density functional computations of the energetic and spectroscopic parameters of quercetin and its radicals in the gas phase and in solvent
    • M. Leopoldini, T. Marino, N. Russo and M. Toscano, Density functional computations of the energetic and spectroscopic parameters of quercetin and its radicals in the gas phase and in solvent. Theor. Chem. Acc. 111, 210-216 (2004).
    • (2004) Theor. Chem. Acc , vol.111 , pp. 210-216
    • Leopoldini, M.1    Marino, T.2    Russo, N.3    Toscano, M.4
  • 21
    • 0034868284 scopus 로고    scopus 로고
    • O-H bond dissociation energies of phenolic compounds are determined by field/inductive effect or resonance effect? A DFT study and its implication
    • H. Y. Zhang, Y. M. Sun and D. Z. Chen, O-H bond dissociation energies of phenolic compounds are determined by field/inductive effect or resonance effect? A DFT study and its implication. QSAR 20, 148-152 (2001).
    • (2001) QSAR , vol.20 , pp. 148-152
    • Zhang, H.Y.1    Sun, Y.M.2    Chen, D.Z.3
  • 22
    • 0037455262 scopus 로고    scopus 로고
    • Substituent effects on OH bond dissociation enthalpies and ionization potentials of catechols: A DFT study and its implications in the rational design of phenolic antioxidants and elucidation of structure-activity relationships for flavonoid antioxidants
    • H. Y. Zhang, Y. M. Sun and X. L. Wang, Substituent effects on OH bond dissociation enthalpies and ionization potentials of catechols: A DFT study and its implications in the rational design of phenolic antioxidants and elucidation of structure-activity relationships for flavonoid antioxidants. Chem-Eur. J. 9, 502-508 (2003).
    • (2003) Chem-Eur. J , vol.9 , pp. 502-508
    • Zhang, H.Y.1    Sun, Y.M.2    Wang, X.L.3
  • 23
    • 0035478933 scopus 로고    scopus 로고
    • The influence of pH on antioxidant properties and the mechanism of antioxidant action of hydroxyflavones
    • K. Lemaska, H. Szymusiak, B. Tyrakowska and R. Zieliski, The influence of pH on antioxidant properties and the mechanism of antioxidant action of hydroxyflavones. Free Radic. Biol. Med. 31, 869-881 (2001).
    • (2001) Free Radic. Biol. Med , vol.31 , pp. 869-881
    • Lemaska, K.1    Szymusiak, H.2    Tyrakowska, B.3    Zieliski, R.4
  • 24
    • 0142011665 scopus 로고    scopus 로고
    • Role of phenolic O-H and methylene hydrogen on the free radical reactions and antioxidant activity of curcumin
    • K. I. Priyadarsini, D. K. Maity, G. H. Naik, M. S. Kumar, M. K. Unnikrishnan and J. G. Satav, Role of phenolic O-H and methylene hydrogen on the free radical reactions and antioxidant activity of curcumin. Free Radic. Biol. Med. 35, 475-484 (2003).
    • (2003) Free Radic. Biol. Med , vol.35 , pp. 475-484
    • Priyadarsini, K.I.1    Maity, D.K.2    Naik, G.H.3    Kumar, M.S.4    Unnikrishnan, M.K.5    Satav, J.G.6
  • 25
    • 84981654257 scopus 로고
    • Spin-unrestricted character of Kohn-Sham orbitals for open-shell systems
    • J. A. Pople, P. M. W. Gill and N. C. Handy, Spin-unrestricted character of Kohn-Sham orbitals for open-shell systems. Int. J. Quantum Chem. 56, 303-305 (1995).
    • (1995) Int. J. Quantum Chem , vol.56 , pp. 303-305
    • Pople, J.A.1    Gill, P.M.W.2    Handy, N.C.3
  • 26
    • 5944261746 scopus 로고
    • Density-functional approximation for the correlation energy of the inhomogeneous electron gas
    • J. P. Perdew, Density-functional approximation for the correlation energy of the inhomogeneous electron gas. Phys. Rev. B 33, 8822-8824 (1986).
    • (1986) Phys. Rev. B , vol.33 , pp. 8822-8824
    • Perdew, J.P.1
  • 27
    • 0000189651 scopus 로고
    • Density-functional thermochemistry. III. The role of exact exchange
    • A. D. Becke, Density-functional thermochemistry. III. The role of exact exchange. J. Chem. Phys. 98, 5648-5652 (1993).
    • (1993) J. Chem. Phys , vol.98 , pp. 5648-5652
    • Becke, A.D.1
  • 28
    • 0031209054 scopus 로고    scopus 로고
    • A new integral equation formalism for the polarizable continuum model: Theoretical background and applications to isotropic and anisotropic dielectrics
    • E. Cancès, B. Mennucci and J. Tomasi, A new integral equation formalism for the polarizable continuum model: Theoretical background and applications to isotropic and anisotropic dielectrics. J. Chem. Phys. 107, 3032-3041 (1997).
    • (1997) J. Chem. Phys , vol.107 , pp. 3032-3041
    • Cancès, E.1    Mennucci, B.2    Tomasi, J.3
  • 29
    • 0032502372 scopus 로고    scopus 로고
    • Ab initio study of ionic solutions by a polarizable continuum dielectric model
    • M. Cossi, V. Barone, B. Mennucci and J. Tomasi, Ab initio study of ionic solutions by a polarizable continuum dielectric model. Chem. Phys. Lett. 286, 253-260 (1998).
    • (1998) Chem. Phys. Lett , vol.286 , pp. 253-260
    • Cossi, M.1    Barone, V.2    Mennucci, B.3    Tomasi, J.4
  • 30
    • 84961979198 scopus 로고    scopus 로고
    • Continuum solvation models: A new approach to the problem of solute's charge distribution and cavity boundaries
    • B. Mennucci and J. Tomasi, Continuum solvation models: A new approach to the problem of solute's charge distribution and cavity boundaries. J. Chem. Phys. 106, 5151-5158 (1997).
    • (1997) J. Chem. Phys , vol.106 , pp. 5151-5158
    • Mennucci, B.1    Tomasi, J.2
  • 32
    • 3543004703 scopus 로고    scopus 로고
    • Water effect on the O-H dissociation enthalpy of para-substituted phenols: A DFT study
    • M. Guerra, R. Amorati and G. F. Pedulli, Water effect on the O-H dissociation enthalpy of para-substituted phenols: a DFT study. J. Org. Chem. 69, 5460-5467 (2004).
    • (2004) J. Org. Chem , vol.69 , pp. 5460-5467
    • Guerra, M.1    Amorati, R.2    Pedulli, G.F.3
  • 33
    • 1342323567 scopus 로고    scopus 로고
    • Correlated ab initio study of nucleic acid bases and their tautomers in the gas phase, in a microhydrated environment, and in aqueous solution. Part 3. Adenine
    • M. Hanus, M. Kabelác, J. Rejnek, F. Ryjácek and P. Hobza, Correlated ab initio study of nucleic acid bases and their tautomers in the gas phase, in a microhydrated environment, and in aqueous solution. Part 3. Adenine. J. Phys. Chem. B 108, 2087-2097 (2004).
    • (2004) J. Phys. Chem. B , vol.108 , pp. 2087-2097
    • Hanus, M.1    Kabelác, M.2    Rejnek, J.3    Ryjácek, F.4    Hobza, P.5
  • 34
    • 39749091307 scopus 로고    scopus 로고
    • H. Fricke and E. J. Hart, In Radiation Dosimetry, II, Instrumentation (F. H. Attix, W. C. Roesch and E. Tochilin, Eds.), pp. 167-237. Academic Press, New York, 1966.
    • H. Fricke and E. J. Hart, In Radiation Dosimetry, Vol. II, Instrumentation (F. H. Attix, W. C. Roesch and E. Tochilin, Eds.), pp. 167-237. Academic Press, New York, 1966.
  • 37
    • 0000896724 scopus 로고
    • The radiation chemistry of liquid methanol. I. The oxidizing radical
    • F. Dainton, I. Janovsky and G. A. Salmon, The radiation chemistry of liquid methanol. I. The oxidizing radical. Proc. R. Soc. Lond. A 327, 305-316 (1972).
    • (1972) Proc. R. Soc. Lond. A , vol.327 , pp. 305-316
    • Dainton, F.1    Janovsky, I.2    Salmon, G.A.3
  • 38
    • 0030251450 scopus 로고    scopus 로고
    • Quelques aspects actuels de la radiolyse du méthanol liquide: Une revue.
    • C. Ferradini and J. P. Jay-Gerin, Quelques aspects actuels de la radiolyse du méthanol liquide: une revue. Radiat. Phys. Chem. 48, 473-480 (1996).
    • (1996) Radiat. Phys. Chem , vol.48 , pp. 473-480
    • Ferradini, C.1    Jay-Gerin, J.P.2
  • 39
    • 14344266527 scopus 로고    scopus 로고
    • 2OH and its involvement in the dissociation of the methanol dimer radical cation: A Quid pro Quo reaction
    • 2OH and its involvement in the dissociation of the methanol dimer radical cation: A Quid pro Quo reaction. Int. J. Mass Spectrom. 242, 49-56 (2005).
    • (2005) Int. J. Mass Spectrom , vol.242 , pp. 49-56
    • Burgers, P.C.1    Ruttink, P.J.A.2
  • 43
    • 0033151430 scopus 로고    scopus 로고
    • Selecting ethanol as a model organic solvent in radiation chemistry - 4: Radiation chemistry of diallyl sulphide in ethanol solution
    • G. Wang and J. Wu, Selecting ethanol as a model organic solvent in radiation chemistry - 4: Radiation chemistry of diallyl sulphide in ethanol solution. Radiat Phys. Chem. 55, 25-34 (1999).
    • (1999) Radiat Phys. Chem , vol.55 , pp. 25-34
    • Wang, G.1    Wu, J.2
  • 44
    • 33748322763 scopus 로고
    • The elucidation of peroxyl radical reactions in aqueous solution with the help of radiation-chemical methods
    • C. von Sonntag and H. P. Schuchmann, The elucidation of peroxyl radical reactions in aqueous solution with the help of radiation-chemical methods. Angew Chem. Int. Ed. Engl. 30, 1229-1253 (1991).
    • (1991) Angew Chem. Int. Ed. Engl , vol.30 , pp. 1229-1253
    • von Sonntag, C.1    Schuchmann, H.P.2
  • 45
    • 33847372916 scopus 로고    scopus 로고
    • A density functional theory study of the conformational, electronic and antioxidant properties of natural chalcones
    • in press
    • D. Kozlowski, P. Trouillas, C. Calliste, P. Marsal, R. Lazzaroni and J. L. Duroux, A density functional theory study of the conformational, electronic and antioxidant properties of natural chalcones. J. Phys. Chem. A, in press.
    • J. Phys. Chem. A
    • Kozlowski, D.1    Trouillas, P.2    Calliste, C.3    Marsal, P.4    Lazzaroni, R.5    Duroux, J.L.6
  • 47
    • 0029655568 scopus 로고    scopus 로고
    • Hydroxylethylation of baicalin by γ-ray irradiation of baicalin in ethanol
    • C. Zhongli, H. Yongke and W. Jilan, Hydroxylethylation of baicalin by γ-ray irradiation of baicalin in ethanol. Radiat. Phys. Chem. 47, 213-215 (1996).
    • (1996) Radiat. Phys. Chem , vol.47 , pp. 213-215
    • Zhongli, C.1    Yongke, H.2    Jilan, W.3
  • 48
    • 0030175778 scopus 로고    scopus 로고
    • Study of baicalin scavenging hydroxyethyl peroxyl radicals by radiolysis of aerated ethanol-baicalin system
    • C. Zhongli, H. Yongke and W. Jilan, Study of baicalin scavenging hydroxyethyl peroxyl radicals by radiolysis of aerated ethanol-baicalin system. Radiat. Phys. Chem. 47, 869-871 (1996).
    • (1996) Radiat. Phys. Chem , vol.47 , pp. 869-871
    • Zhongli, C.1    Yongke, H.2    Jilan, W.3
  • 49
    • 0002972267 scopus 로고    scopus 로고
    • Synthesis and characterization of copper(I) and copper(II) flavonolate complexes with phthalazine ligand, and their oxygenation and relevance to quercetinase
    • E. Balogh-Hergovich, J. Kaizer and G. Speier, Synthesis and characterization of copper(I) and copper(II) flavonolate complexes with phthalazine ligand, and their oxygenation and relevance to quercetinase. Inorg. Chim. Acta 256, 9-14 (1997).
    • (1997) Inorg. Chim. Acta , vol.256 , pp. 9-14
    • Balogh-Hergovich, E.1    Kaizer, J.2    Speier, G.3
  • 52
    • 4644364662 scopus 로고    scopus 로고
    • Hybrid DFT study of the mechanism of quercetin 2,3-dioxygenase
    • P. E. M. Siegbahn, Hybrid DFT study of the mechanism of quercetin 2,3-dioxygenase. Inorg. Chem. 43, 5944-5953 (2004).
    • (2004) Inorg. Chem , vol.43 , pp. 5944-5953
    • Siegbahn, P.E.M.1
  • 53
    • 9644281121 scopus 로고    scopus 로고
    • Oxygenolysis of flavonoid compounds: DFT description of the mechanism for quercetin
    • S. Fiorucci, J. Golebiowski, D. Cabrol-Bass and S. Antonczak, Oxygenolysis of flavonoid compounds: DFT description of the mechanism for quercetin. Chem. Phys. Chem. 5, 1726-1733 (2004).
    • (2004) Chem. Phys. Chem , vol.5 , pp. 1726-1733
    • Fiorucci, S.1    Golebiowski, J.2    Cabrol-Bass, D.3    Antonczak, S.4
  • 54
    • 4444298087 scopus 로고    scopus 로고
    • Liquid chromatographic/ electrospray ionization mass spectrometric identification of the oxidation end-products of metformin in aqueous solutions
    • F. Collin, H. Khoury, D. Bonnefont-Rousselot, P. Thérond, A. Legrand, D. Jore and M. Gardés-Albert, Liquid chromatographic/ electrospray ionization mass spectrometric identification of the oxidation end-products of metformin in aqueous solutions. J. Mass Spectrom. 39, 890-902 (2004).
    • (2004) J. Mass Spectrom , vol.39 , pp. 890-902
    • Collin, F.1    Khoury, H.2    Bonnefont-Rousselot, D.3    Thérond, P.4    Legrand, A.5    Jore, D.6    Gardés-Albert, M.7
  • 55
    • 0036847989 scopus 로고    scopus 로고
    • Gamma radiolysis of ethyl t-butyl ether: A study of hydroxyl radical mediated reaction pathways
    • T. Wu, V. Cruz, S. Mezyk, W. J. Cooper and K. E. O'Shea, Gamma radiolysis of ethyl t-butyl ether: a study of hydroxyl radical mediated reaction pathways. Radiat. Phys. Chem. 65, 335-341 (2002).
    • (2002) Radiat. Phys. Chem , vol.65 , pp. 335-341
    • Wu, T.1    Cruz, V.2    Mezyk, S.3    Cooper, W.J.4    O'Shea, K.E.5


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.