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M. S. S. Kumar - One of the best experts on this subject based on the ideXlab platform.
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molecular interaction study of binary mixtures of Methyl Benzoate viscometric and ultrasonic study
Journal of Molecular Liquids, 2012Co-Authors: Manapragada V. Rathnam, Reema T Sayed, Kavita R Bhanushali, M. S. S. KumarAbstract:Abstract Densities ( ρ ), viscosities ( η ) and ultrasonic speeds ( u ) of binary mixtures of Methyl Benzoate with benzene, isopropyl benzene, isobutyl benzene, acetophenone, cyclopentanone, cyclohexanone or 3-pentanone including those of pure liquids were measured over the entire composition range at temperatures 303.15 and 313.15 K respectively. The excess molar volumes ( V E ) and the other excess thermodynamic properties such as deviations in isentropic compressibilities (Δ k s ), ultrasonic speed (∆ u ), viscosity (∆ η ) and excess free energy of activation (∆ G ⁎ E ) were calculated using the experimentally measured ρ , η and u respectively. The experimental mixture viscosities were analyzed on the basis of Tamura–Kurata, Heric (2-Parameter), Eyring–Margules and Jouyban–Acree models. A good agreement among experimental data and the values estimated by theoretical procedure was obtained.
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Density, Viscosity, and Speed of Sound of (Methyl Benzoate + Cyclohexane), (Methyl Benzoate + n-Hexane), (Methyl Benzoate + Heptane), and (Methyl Benzoate + Octane) at Temperatures of (303.15, 308.15, and 313.15) K
Journal of Chemical & Engineering Data, 2010Co-Authors: Manapragada V. Rathnam, Sharad Mankumare, M. S. S. KumarAbstract:Density, viscosity, and speed of sound data of (Methyl Benzoate + cyclohexane), (Methyl Benzoate + n-hexane), (Methyl Benzoate + heptane), and (Methyl Benzoate + octane) have been determined at T = (303.15, 308.15, and 313.15) K. From this data, excess volume, VE, and isentropic compressibility, Ks, have been estimated. The values of VE for (Methyl Benzoate + cyclohexane) are very largely positive, while for (Methyl Benzoate + octane) they are both positive and negative and for the remaining mixtures negative. The VE were fitted to the Redlich−Kister polynomial equation. The measured viscosities were correlated with Auslander and McAllister’s four-body interaction models.
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density viscosity and speed of sound of Methyl Benzoate cyclohexane Methyl Benzoate n hexane Methyl Benzoate heptane and Methyl Benzoate octane at temperatures of 303 15 308 15 and 313 15 k
Journal of Chemical & Engineering Data, 2010Co-Authors: Manapragada V. Rathnam, Sharad Mankumare, M. S. S. KumarAbstract:Density, viscosity, and speed of sound data of (Methyl Benzoate + cyclohexane), (Methyl Benzoate + n-hexane), (Methyl Benzoate + heptane), and (Methyl Benzoate + octane) have been determined at T = (303.15, 308.15, and 313.15) K. From this data, excess volume, VE, and isentropic compressibility, Ks, have been estimated. The values of VE for (Methyl Benzoate + cyclohexane) are very largely positive, while for (Methyl Benzoate + octane) they are both positive and negative and for the remaining mixtures negative. The VE were fitted to the Redlich−Kister polynomial equation. The measured viscosities were correlated with Auslander and McAllister’s four-body interaction models.
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thermophysical properties of isoamyl acetate or Methyl Benzoate hydrocarbon binary mixtures at 303 15 and 313 15 k
Journal of Chemical & Engineering Data, 2009Co-Authors: Manapragada V. Rathnam, Sudhir Mohite, M. S. S. KumarAbstract:Densities, viscosities, and refractive indices have been measured for the binary liquid mixtures of isoamyl acetate or Methyl Benzoate with (o-, m-, and p-) xylenes and ethylbenzene over the entire composition range at (303.15 and 313.15) K. From the experimental data, the values of viscosity deviations Δη and deviation in molar refraction ΔR have been determined. The values of Δη and ΔR have been fitted to the Redlich−Kister polynomial equation to determine the binary coefficients and the standard deviation. The predictive ability of several one-, two-, and three-parameter viscosity models was also tested. It was observed that the viscosities were best correlated with the McAllister equation.
Kiran Sankar Maiti - One of the best experts on this subject based on the ideXlab platform.
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Structural sensitivity of CH vibrational band in Methyl Benzoate.
Spectrochimica acta. Part A Molecular and biomolecular spectroscopy, 2018Co-Authors: Susmita Roy, Kiran Sankar MaitiAbstract:Abstract The C H vibrational bands of Methyl Benzoate are studied to understand its coupling pattern with other vibrational bands of the biological molecule. This will facilitate to understand the biological structure and dynamics in spectroscopic as well as in microscopic study. Due to the congested spectroscopic pattern, near degeneracy, and strong anharmonicity of the C H stretch vibrations, assignment of the C H vibrational frequencies are often misleading. Anharmonic vibrational frequency calculation with multidimensional potential energy surface interprets the C H vibrational spectra more accurately. In this article we have presented the importance of multidimensional potential energy surface in anharmonic vibrational frequency calculation and discuss the unexpected red shift of asymmetric C H stretch vibration of Methyl group. The C D stretch vibrational band which is splitted to double peaks due to the Fermi resonance is also discussed here.
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Unexpected red shift of C-H vibrational band of Methyl Benzoate
arXiv: Chemical Physics, 2016Co-Authors: Kiran Sankar Maiti, Susmita Roy, Christoph ScheurerAbstract:The C-H vibrational bands become more and more important in the structural determination of biological molecules with the development of CARS microscopy and 2DIR spectroscopy. Due to the congested pattern, near degeneracy, and strong anharmonicity of the C-H stretch vibrations, assignment of the C-H vibrational bands are often misleading. Anharmonic vibrational spectra calculation with multidimensional potential energy surface interprets the C-H vibrational spectra more accurately. In this article we have presented the importance of multidimensional potential energy surface in anharmonic vibrational spectra calculation and discuss the unexpected red shift of C-H vibrational band of Methyl Benzoate.
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Vibrational spectroscopy of Methyl Benzoate
Physical chemistry chemical physics : PCCP, 2015Co-Authors: Kiran Sankar MaitiAbstract:Methyl Benzoate is studied as a model compound for the development of new IR pulse schemes with possible applicability to biomolecules. Anharmonic vibrational modes of Methyl Benzoate are calculated on different level (MP2, SCS, CCSD(T) with varying basis sets) ab initio PESs using the vibrational self-consistent field (VSCF) method and its correlation corrected extensions. Dual level schemes, combining different quantum chemical methods for diagonal and coupling potentials, are systematically studied and applied successfully to reduce the computational cost. Isotopic substitution of β-hydrogen by deuterium is studied to obtain a better understanding of the molecular vibrational coupling topology.
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Vibrational Spectroscopy of Methyl Benzoate
arXiv: Chemical Physics, 2014Co-Authors: Kiran Sankar Maiti, Christoph ScheurerAbstract:Methyl Benzoate (MB) is studied as a model compound for the development of new IR pulse schemes with possible applicability to biomolecules. Anharmonic vibrational modes of MB are calculated on different level (MP2, SCS, CCSD(T) with varying basis sets) ab-initio PESs using the vibrational self-consistent field (VSCF) method and its correlation corrected extensions. Dual level schemes, combining different quantum chemical methods for diagonal and coupling potentials, are systematically studied and applied successfully to reduce the computational cost. Isotopic substitution of {\beta}-hydrogen by deuterium is studied to obtain a better understanding of the molecular vibrational coupling topology.
Manapragada V. Rathnam - One of the best experts on this subject based on the ideXlab platform.
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molecular interaction study of binary mixtures of Methyl Benzoate viscometric and ultrasonic study
Journal of Molecular Liquids, 2012Co-Authors: Manapragada V. Rathnam, Reema T Sayed, Kavita R Bhanushali, M. S. S. KumarAbstract:Abstract Densities ( ρ ), viscosities ( η ) and ultrasonic speeds ( u ) of binary mixtures of Methyl Benzoate with benzene, isopropyl benzene, isobutyl benzene, acetophenone, cyclopentanone, cyclohexanone or 3-pentanone including those of pure liquids were measured over the entire composition range at temperatures 303.15 and 313.15 K respectively. The excess molar volumes ( V E ) and the other excess thermodynamic properties such as deviations in isentropic compressibilities (Δ k s ), ultrasonic speed (∆ u ), viscosity (∆ η ) and excess free energy of activation (∆ G ⁎ E ) were calculated using the experimentally measured ρ , η and u respectively. The experimental mixture viscosities were analyzed on the basis of Tamura–Kurata, Heric (2-Parameter), Eyring–Margules and Jouyban–Acree models. A good agreement among experimental data and the values estimated by theoretical procedure was obtained.
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Density, Viscosity, and Speed of Sound of (Methyl Benzoate + Cyclohexane), (Methyl Benzoate + n-Hexane), (Methyl Benzoate + Heptane), and (Methyl Benzoate + Octane) at Temperatures of (303.15, 308.15, and 313.15) K
Journal of Chemical & Engineering Data, 2010Co-Authors: Manapragada V. Rathnam, Sharad Mankumare, M. S. S. KumarAbstract:Density, viscosity, and speed of sound data of (Methyl Benzoate + cyclohexane), (Methyl Benzoate + n-hexane), (Methyl Benzoate + heptane), and (Methyl Benzoate + octane) have been determined at T = (303.15, 308.15, and 313.15) K. From this data, excess volume, VE, and isentropic compressibility, Ks, have been estimated. The values of VE for (Methyl Benzoate + cyclohexane) are very largely positive, while for (Methyl Benzoate + octane) they are both positive and negative and for the remaining mixtures negative. The VE were fitted to the Redlich−Kister polynomial equation. The measured viscosities were correlated with Auslander and McAllister’s four-body interaction models.
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density viscosity and speed of sound of Methyl Benzoate cyclohexane Methyl Benzoate n hexane Methyl Benzoate heptane and Methyl Benzoate octane at temperatures of 303 15 308 15 and 313 15 k
Journal of Chemical & Engineering Data, 2010Co-Authors: Manapragada V. Rathnam, Sharad Mankumare, M. S. S. KumarAbstract:Density, viscosity, and speed of sound data of (Methyl Benzoate + cyclohexane), (Methyl Benzoate + n-hexane), (Methyl Benzoate + heptane), and (Methyl Benzoate + octane) have been determined at T = (303.15, 308.15, and 313.15) K. From this data, excess volume, VE, and isentropic compressibility, Ks, have been estimated. The values of VE for (Methyl Benzoate + cyclohexane) are very largely positive, while for (Methyl Benzoate + octane) they are both positive and negative and for the remaining mixtures negative. The VE were fitted to the Redlich−Kister polynomial equation. The measured viscosities were correlated with Auslander and McAllister’s four-body interaction models.
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thermophysical properties of isoamyl acetate or Methyl Benzoate hydrocarbon binary mixtures at 303 15 and 313 15 k
Journal of Chemical & Engineering Data, 2009Co-Authors: Manapragada V. Rathnam, Sudhir Mohite, M. S. S. KumarAbstract:Densities, viscosities, and refractive indices have been measured for the binary liquid mixtures of isoamyl acetate or Methyl Benzoate with (o-, m-, and p-) xylenes and ethylbenzene over the entire composition range at (303.15 and 313.15) K. From the experimental data, the values of viscosity deviations Δη and deviation in molar refraction ΔR have been determined. The values of Δη and ΔR have been fitted to the Redlich−Kister polynomial equation to determine the binary coefficients and the standard deviation. The predictive ability of several one-, two-, and three-parameter viscosity models was also tested. It was observed that the viscosities were best correlated with the McAllister equation.
Natalia Dudareva - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of the food flavoring Methyl Benzoate by genetically engineered Saccharomyces cerevisiae.
Journal of biotechnology, 2006Co-Authors: Moran Farhi, Natalia Dudareva, Tania Masci, David J. Weiss, Alexander Vainstein, Hagai AbeliovichAbstract:Current means of production for plant-derived aroma compounds include chemical synthesis and extraction from plant material. Both methods are environmentally detrimental and relatively expensive: plant material is only seasonally available and only a small subset of the plant biomass produces the desired aroma compounds, while organic synthesis inevitably involves waste byproducts with a negative ecological impact. Benzenoids are a class of plant metabolites that includes a number of aroma compounds. This paper explores, for the first time, the feasibility of producing benzenoids in yeast. We present a method for the production of the phenylpropanoid Methyl Benzoate in Saccharomyces cerevisiae using benzoic acid as a substrate, by heterologous expression of Antirrhinum majus benzoic acid Methyl transferase. Production was pH dependent with a maximal yield of approximately 50 microg of Methyl Benzoate per liter of culture per hour, and with linear kinetics over at least 24 h. In addition, we have analyzed two alternative expression vectors for the production of benzoic acid Methyl transferase in S. cerevisiae: a constitutive triosephosphate isomerase promoter-based system was compared with a copper-inducible CUP1 promoter system. We find major differences in the amounts of MethylBenzoate produced by these respective systems. Potential applications are discussed.
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Novel S-adenosyl-L-methionine:salicylic acid carboxyl Methyltransferase, an enzyme responsible for biosynthesis of Methyl salicylate and Methyl Benzoate, is not involved in floral scent production in snapdragon flowers.
Archives of Biochemistry and Biophysics, 2002Co-Authors: Florence Negre, Christine M Kish, Natalia Kolosova, Joseph Knoll, Natalia DudarevaAbstract:Using a functional genomic approach we have isolated and characterized a cDNA that encodes a salicylic acid carboxyl Methyltransferase (SAMT) from Antirrhinum majus. The sequence of the protein encoded by SAMT has higher amino acid identity to Clarkia breweri SAMT than to snapdragon benzoic acid carboxyl Methyltransferase (BAMT) (55 and 40% amino acid identity, respectively). Escherichia coli-expressed SAMT protein catalyzes the formation of the volatile ester Methyl salicylate from salicylic acid with a K(m) value of 83 microM. It can also Methylate benzoic acid to form Methyl Benzoate, but its K(m) value for benzoic acid is 1.72 mM. Snapdragon flowers do not emit Methyl salicylate. The potential involvement of SAMT in production and emission of Methyl Benzoate in snapdragon flowers was analyzed by RNA gel blot analysis. SAMT mRNA was not detected in floral tissues by RNA blot hybridization, but low levels of SAMT gene expression were detected after real-time RT-PCR in the presence of SAMT-specific primers, indicating that this gene does not contribute significantly, if at all, in Methyl Benzoate production and emission in snapdragon flowers. Expression of SAMT in petal tissue was found to be induced by salicylic and jasmonic acid treatments.
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regulation of circadian Methyl Benzoate emission in diurnally and nocturnally emitting plants
The Plant Cell, 2001Co-Authors: Natalia Kolosova, Christine M Kish, Nina M Gorenstein, Natalia DudarevaAbstract:Emission of Methyl Benzoate, one of the most abundant scent compounds of bee-pollinated snapdragon flowers, occurs in a rhythmic manner, with maximum emission during the day, and coincides with the foraging activity of bumblebees. Rhythmic emission of Methyl Benzoate displays a “free-running” cycle in the absence of environmental cues (in continuous dark or continuous light), indicating the circadian nature of diurnal rhythmicity. Methyl Benzoate is produced in upper and lower snapdragon petal lobes by enzymatic Methylation of benzoic acid in the reaction catalyzed by S-adenosyl-l-methionine:benzoic acid carboxyl Methyltransferase (BAMT). When a detailed time-course analysis of BAMT activity in upper and lower petal lobes during a 48-hr period was performed, high BAMT activity was found at night as well as in continuous darkness, indicating that the BAMT activity is not an oscillation-determining factor. Analysis of the level of benzoic acid during a 24-hr period revealed oscillations in the amount of benzoic acid during the daily light/dark cycle that were retained in continuous darkness. These data clearly show that the total amount of substrate (benzoic acid) in the cell is involved in the regulation of the rhythmic emission of Methyl Benzoate. Our results also suggest that similar molecular mechanisms are involved in the regulation of Methyl Benzoate production in diurnally (snapdragon) and nocturnally (tobacco and petunia) emitting plants.
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developmental regulation of Methyl Benzoate biosynthesis and emission in snapdragon flowers
The Plant Cell, 2000Co-Authors: Natalia Dudareva, Christine M Kish, Natalia Kolosova, Lisa M Murfitt, Craig J Mann, Nina M Gorenstein, Connie C Bonham, Karl V WoodAbstract:In snapdragon flowers, the volatile ester Methyl Benzoate is the most abundant scent compound. It is synthesized by and emitted from only the upper and lower lobes of petals, where pollinators (bumblebees) come in contact with the flower. Emission of Methyl Benzoate occurs in a rhythmic manner, with maximum emission during the day, which correlates with pollinator activity. A novel S-adenosyl-l-methionine:benzoic acid carboxyl Methyl transferase (BAMT), the final enzyme in the biosynthesis of Methyl Benzoate, and its corresponding cDNA have been isolated and characterized. The complete amino acid sequence of the BAMT protein has only low levels of sequence similarity to other previously characterized proteins, including plant O-Methyl transferases. During the life span of the flower, the levels of Methyl Benzoate emission, BAMT activity, BAMT gene expression, and the amounts of BAMT protein and benzoic acid are developmentally and differentially regulated. Linear regression analysis revealed that production of Methyl Benzoate is regulated by the amount of benzoic acid and the amount of BAMT protein, which in turn is regulated at the transcriptional level.
Zhenlu Wang - One of the best experts on this subject based on the ideXlab platform.
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a highly effective cu zno al 2 o 3 catalyst for hydrogenation of Methyl Benzoate to benzyl alcohol in methanol solution
Catalysis Letters, 2019Co-Authors: Ye Jiang, Yifan Wu, Li Zhang, Bin Zheng, Zhenlu WangAbstract:The Cu/ZnO/Al2O3 catalysts prepared by co-precipitation method were used for the hydrogenation of Methyl Benzoate to benzyl alcohol. These catalysts were characterized at various stages of preparation by nitrogen adsorption–desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The experimental results show that the addition of ZnO to the catalyst greatly improves the selectivity of benzyl alcohol. When the Cu/Zn/Al molar ratio is 2:2:1 and the calcination temperature of the catalyst is 650 °C, the catalyst exhibits very highly catalytic performance. In addition, the effects of reaction temperature, pressure and time were also investigated during the hydrogenation of Methyl Benzoate to benzyl alcohol. When the Methyl Benzoate was hydrogenated over this catalyst at 160 °C and 7 MPa of H2 for 10 h, the conversion of Methyl Benzoate can reach 93.89% and the selectivity of benzyl alcohol is 88%. This effectively catalytic performance can be attributed to the presence of highly dispersed and stable metallic copper nanoparticles, and the weak acidity of the catalyst surface. Besides, the reaction pressure and temperature play a crucial role in the conversion of Methyl Benzoate and the selectivity of benzyl alcohol. Application of Cu/ZnO/Al2O3 catalyst in hydrogenation of Methyl Benzoate to benzyl alcohol.
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A Highly Effective Cu/ZnO/Al 2 O 3 Catalyst for Hydrogenation of Methyl Benzoate to Benzyl Alcohol in Methanol Solution
Catalysis Letters, 2019Co-Authors: Ye Jiang, Li Zhang, Bin Zheng, Qiang Bao, Wenying Gui, Xiaofei Liu, Zhenlu WangAbstract:The Cu/ZnO/Al2O3 catalysts prepared by co-precipitation method were used for the hydrogenation of Methyl Benzoate to benzyl alcohol. These catalysts were characterized at various stages of preparation by nitrogen adsorption–desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The experimental results show that the addition of ZnO to the catalyst greatly improves the selectivity of benzyl alcohol. When the Cu/Zn/Al molar ratio is 2:2:1 and the calcination temperature of the catalyst is 650 °C, the catalyst exhibits very highly catalytic performance. In addition, the effects of reaction temperature, pressure and time were also investigated during the hydrogenation of Methyl Benzoate to benzyl alcohol. When the Methyl Benzoate was hydrogenated over this catalyst at 160 °C and 7 MPa of H2 for 10 h, the conversion of Methyl Benzoate can reach 93.89% and the selectivity of benzyl alcohol is 88%. This effectively catalytic performance can be attributed to the presence of highly dispersed and stable metallic copper nanoparticles, and the weak acidity of the catalyst surface. Besides, the reaction pressure and temperature play a crucial role in the conversion of Methyl Benzoate and the selectivity of benzyl alcohol. Application of Cu/ZnO/Al2O3 catalyst in hydrogenation of Methyl Benzoate to benzyl alcohol.