• Bulletin of Food Technology
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• v.24 no.2
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• pp.178-186
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• 2011

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.823-826
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• 2013

A low-${\varepsilon}$ solid-state NMR(Nuclear Magnetic Resonance) probe was developed for the spectroscopic analysis of two-dimensional $^{15}N-^1H$ heteronuclear dipolar coupling in dilute membrane proteins oriented in hydrated and dielectrically lossy lipid environments. The system employed a 800 MHz narrow-bore magnet. A solenoid coil strip shield was used to reduce deleterious RF sample heating by minimizing the conservative electric fields generated by the double-tuned resonator at high magnetic fields. The probe's design, construction, and performance in solid-state NMR experiments at high magnetic fields are described here. Such high-resolution solid-state NMR spectroscopic analysis of static oriented samples in hydrated phospholipid bilayers or bicelles could aid the structural analysis of dilute biological membrane proteins.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.615-617
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• 2005

[ $^{13}C$ ] NMR spectra were obtained for pure $CH_4$ hydrate in order to identify hydrate structure and cage occupancy of guest molecule. The NMR technique can provide both qualitative and quantitative hydrate characteristics. The moles of methane captured into pure $CH_4$ hydrate per mole of water were found to be similar to the full occupancy value. The overall results drawn from this study can be usefully applied to storage and transportation of natural gas.

• Korean Journal of Pharmacognosy
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• v.19 no.3
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• pp.153-169
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• 1988

The combined use of the J-modulated selective INEPT and CSCM 1DNMR techniques is described for the structure elucidation of several new classes of compound including prionitin, the loureirins and larreantin, and for the regiosubstitution of the furanonaphthoquinones. Spectroscopic studies on the conformation of the cytotoxic agent savinin are also described, together with the NMR assignments and preliminary biosynthetic experiments on the antitumor antibiotic staurosporine.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.1
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• pp.27-35
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• 2016

NMR spectrometer has been regarded as essential tool for structure elucidation in variable scientific field as like organic synthesis, natural product and macro protein research. Also NMR can be applied for defining dynamic behavior like ligand and receptor binding. One of advantage of research with NMR is that to be great confident to confirm structure and the measured sample could be recovered. Nevertheless NMR also has a weak points than other spectroscopic methods that require a lot of time for interpreting acquired spectrum and running time due to low sensitivity. For last two decade Bruker has developed hardware and software solution for overcome those weak points. In order to overcome low sensitivity Bruker introduced Cryo and Micro diameter probe head technology. And researcher can reduce the time for routine spectrum processing and interpretation works due to lots of introductions in software solutions for quantification, identification and statistics analysis. With four examples, this article describing those new hardware and software solutions in field of recent pharmaceutical research as follows. - New Horizons for NMR in the Biopharmaceutical Industry - The development and application of solid-state NMR spectroscopy (SSNMR) in pharmaceutical analysis - Assisted NMR Data Interpretation in Synthetic Chemistry - Complete Analysis of New Psychoactive Substances Using NMR.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.791-794
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• 2006

Cyclosophoraose (cyclic $\beta-(1,2)-glucan$, Cys) isolated from Rhizobium meliloti, a soil microorganism, was used as a solubility enhancer for flavonoids. The complexes of the cyclic oligosaccharide with flavonoids were confirmed through $^1H$ nuclear magnetic resonance (NMR) spectroscopic analysis. Flavonoids solubilized by Cys were quantitatively analyzed through high-performance liquid chromatography (HPLC). Among the flavonoids tested, the solubility of naringenin was greatly enhanced by Cys, compared with other compounds. The solubility of naringenin was enhanced about 7.1-fold by adding 10 mM Cys, compared with a control. $^1H$ NMR spectroscopic analysis indicated that the H-6 and H-8 protons, which are located on the A ring of naringenin, were greatly shifted upfield upon the complexation with Cys. This result suggested that Cys showed a regioselective interaction with the naringenin molecule upon the complexation, resulting in the solubility enhancement of naringenin.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.93-99
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• 2011

Proton-NMR spectroscopic method was applied to kinetics study of concentrated sulfuric acid hydrolysis reaction. Xylan was used as model compounds. Without neutralization steps in proton-NMR methods, this analysis method is valid for analysis of xylose, furfural and formic acid in acid hydrolyzates.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.216-220
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• 2004

${\beta}$-CD and CM- ${\beta}$-CD as chiral NMR shift agents were used to resolve the enantiomers of noradrenaline (NA). The stoichiometry of each complex formed between the CDs and the enantiomers of NA was found to be 1 : 1 through the continuous variation plots. The binding constants (K) of the complexes were determined from $^1H$ NMR titration curves. This result indicated that both ${\beta}$-CD and CM- ${\beta}$-CD formed the complexes with the S(+)-NA more preferentially than its R(-)-enantiomer. The K values for the complexes with ${\beta}$-CD ($K_{S(+)}$ = 537 $M^{-1}$ and $K_{R(-)}$ = 516 $M^{-1}$ was larger than those with CM- ${\beta}$-CD ($K_{S(+)}$ = 435 $M^{-1}$ and $K_{R(-)}$ = 313 $M^{-1}$), however, enantioselectivity (${\alpha}$) of S(+)- and R(-)-NA to CM- ${\beta}$-CD ( ${\alpha}$ = 1.38) was larger than that to ${\beta}$-CD ( ${\alpha}$ = 1.04), indicating that CM- ${\beta}$-CD was the better chiral NMR solvating agents for the recognition of the enantiomers of NA. Two dimensional rotating frame nuclear Overhauser enhancement spectroscopy (ROESY) experiments were also performed to explain the binding properties in terms of spatial fitting of the NA molecule into the macrocyclic cavities.

• Journal of the Korean Chemical Society
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• v.63 no.2
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• pp.78-84
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• 2019

High-resolution $^1H$ NMR spectroscopic technique has been widely used as one of the most powerful analytical tools in food chemistry as well as to define molecular structure. The $^1H$ NMR spectra-based metabolomics has focused on classification and chemometric analysis of complex mixtures. The principal component analysis (PCA), an unsupervised clustering method and used to reduce the dimensionality of multivariate data, facilitates direct peak quantitation and pattern recognition. Using a combination of these techniques, the various green teas and black teas brewed were investigated via metabolite profiling. These teas were characterized based on the leaf size and country of cultivation, respectively.

• Natural Product Sciences
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• v.17 no.4
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• pp.350-353
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• 2011

A new daucosteryl derivative, verticilloside (1), was isolated from the seeds of Malva verticillata L. (Malvaceae). The structure was determined to be 3-O-[${\beta}$-D-(6'-linoleoyl)glucopyranosyl]-${\beta}$-sitosterol based on spectroscopic analyses ($^1H$ and $^{13}C$-NMR, DEPT, COSY, HMQC, and HMBC) and chemical reactions.