• Archives of Pharmacal Research
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• v.19 no.4
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• pp.302-306
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• 1996

The $^1H- and^{13}C-NMR$ spectra of alaternin, aurantio-obtusin, chryso-obtusin, obtusin and 2-glucosyl obtusifolin isolated from the seeds of Cassia tora have been assigned based on HMBC, long-range HETCOR, fully $^1H-coupled {13}^C-NMR$, deuterium isotope experiment, and by comparison with the model compounds.

• Natural Product Sciences
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• v.4 no.2
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• pp.95-99
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• 1998

The $^{13}C-NMR$ spectrum of nor-rubrofusarin showing strong radical scavenging effect has been assigned by using HMBC and HMQC experiments.

• Analytical Science and Technology
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• v.9 no.2
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• pp.203-209
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• 1996

Kaminsky catalyst system($Et(Ind)_2ZrCl_2$ and MAO(methylaluminoxane)) was prepared. Propylene was polymerized at $60^{\circ}C$ in this system. The microstructure was studied by using the $^{13}C$ NMR spectrometer. From the $^{13}C$ NMR data, the 2, 1-insertion of propylene was controlled stereospecific by Kaminsky catalyst due to the structures of meso and racemo I. After the 2, 1-insertion of propylene, 1, 2-insertion of the chain end was less stereospecifically controlled by the catalyst.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.84-89
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• 2019

To characterize the molecular structure of BzO-gal synthesized using Escherichia coli ${\beta}$-gal, NMR ($^1H$- and $^{13}C$-) spectroscopy and mass spectrometry of BzO-gal were conducted. $^1H$ NMR spectrum of BzO-gal showed multiple peaks corresponding to the galactosyl group, which is an evidence of galactosylation on BzOH. Five proton peaks around the aromatic region at ${\delta}_H$ 7.43 ~ 7.24 ppm and 2 peaks from ${\delta}_H$ 4.93 and 4.67 ppm were evidence of the presence of the benzyl group. Seven proton peaks at ${\delta}_H$ 4.32 ~ 3.46 ppm showed the presence of a monosaccharide and were indicative of galactosylation on BzOH. $^{13}C$ NMR spectrum also revealed the presence of 11 carbons suggestive of BzO-gal. The mass value (sodium adduct ion of BzO-gal, m/z = 293.0994) from mass spectrometry analysis of BzO-gal, and $^1H$ and $^{13}C$ NMR spectral data were in good agreement with the expecting structure of BzO-gal. We are expecting that through future study it will eventually be able to develop a new additive of low cytotoxicity.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1024-1028
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• 1998

Crystalline structure of the extrudate of high amylose corn starch was studied by X-ray diffractometer and $^{13}C\;NMR$. The X-ray diffraction crystal ratio of the extrudates (barrel temperature $100^{\circ}C$ )of high amylose corn starch slightly increased from 6.08% to 8.37% by increasing feed moisture content from 25% to 45%. But extrudates of high amylose corn starch showed similar crystal ratio on various extrusion conditions. Extrudates of high amylose corn starch (feed moisture content 20%, barrel temp $140^{\circ}C$) showed more enlarged crystal structure than that of non-extrudates. The perpendicular distance of crystal increased by extrusion. Crystal ratio was changed from $6.3{\sim}8.3%$ to $4.5{\sim}5.8%$ during storage at $4^{\circ}C$. Starch configuration was examined with $^{13}C\;NMR$. Double helical content was measured by $^{13}C\;NMR$ method. The highest double helical content (60%) was obtained from high amylose corn starch extrudate (barrel temp.: $100^{\circ}C$, feed moisture content 45%). Double helical contents and resistant starch (RS) yield (pancreatin) were positively correlated. However, double helical content of the extrudates was not changed by the storage at $4^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.169-173
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• 1994

The previously reported cytotoxic metabolites, against the KB cell line, xestoquinone, halenaquinol sulfate and $halenaquinol^{5,6}$ were isolated from the unidentified sponge collected in October 1992, Manado Bay, Sulawesi in Indonesia. Their structure were elucidated by $^1H-,\;^{13}C$-NMR, $^1H-,\;^{13}C$(1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy$(HMQC)^1$, $^1H-,\;^{13}C$C(2 and 3 bond) Heteronuclear multiple Bond Correlation Spectroscopy$(HMBC)^2$, Electron Impact Mass Spectroscopy(EI ms), Ultraviolet Spectroscopy(UV), and Infrared Spectroscopy(IR)

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.352-357
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• 2013

This study estimates the classification criteria which distinguishes the types of omega-3 health functional foods, fish oils and fish oil usages through $^{13}C$-NMR spectra and fatty acids contents analysis. The major fatty acids of omega-3, eicosapentaenoic acid (EPA, $C_{20:5}$) and docosahexaenoic acid (DHA, $C_{22:6}$) are being analyzed. 10 ethyl ester (EE) forms and 10 triglyceride (TG) forms are the most common types of fish oils for 20 omega-3 products. Gas chromatography (GC) analysis generally shows the matching EPA and DHA contents of the products listed on the notation. But EE form contents of EPA and DHA are higher and are more varied than the TG form. Most of the samples of EPA/DHA ratio show different content ratios of indicated on the products when comparing with standards. The $^{13}C$-NMR analysis of EPA and DHA on sn-1,3 and sn-2 carbonyl peak position with fish oil triglycerides display whether the reconstituted triglycerides (rTG) are being confirmed or not. As a result of the 9 TG form, the 10 TG products showed similar values: EPA sn-1, 3; 13.46~15.66, sn-2; 3.00~4.52, DHA sn-1, 3; 2.43~4.40, sn-2; 3.84~6.36. But one product showed lower contents (EPA: sn-1, 3; 5.88, sn-2; 2.86, DHA sn-1, 3; 2.29, sn-2; 5.95) of EPA, thus it can be considered a different type of oil and only matched six products according to the label. This study is intended to provide basic materials which identify the status for the types and quality of omega-3 fish oil products according to fatty acids profiles and the $^{13}C$-NMR spectrum confirmed the location specificity of EPA and DHA.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.286-292
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• 2016

1, 2-Hexanediol galactoside (HD-gal) has been synthesized from 1, 2-hexanediol (HD), a cosmetic preservative, using recombinant Escherichia coli ${\beta}$-galactosidase (${\beta}$-gal) at the high lactose concentration (300 g/l). To confirm the molecular structure of synthesized HD-gal, NMR ($^1H$- and $^{13}C$-) spectroscopy and mass spectrometry of HD-gal were conducted. $^1H$ NMR spectrum of HD-gal showed multiple peaks corresponding to the galactocyl group, which is an evidence of galactocylation on HD. Downfield proton peaks at ${\delta}_H$ 4.44 ppm and multiple peaks from ${\delta}_H$3.96~3.58 ppm were indicative of galactocylation on HD. Up field proton peaks at ${\delta}_H$ 1.60~1.35 ppm and 0.92 ppm showed the presence of $CH_2$ and $CH_3$ protons of HD. $^{13}C$ NMR spectrum revealed the presence of 21 carbons suggestive of ${\alpha}$- and ${\beta}$-anomers of HD-gal. Among 12 carbon peaks from each anomers, the 3 peaks at dC 68.6, 60.9 and 13.2 ppm were assigned to be overlapped showing only 21 peaks out of total 24 peaks. The mass value (protonated HD-gal, m/z = 281.1601) from mass spectrometry analysis of HD-gal, and $^1H$ and $^{13}C$ NMR spectral data were in well agreement with the expecting structure of HD-gal. For further study, the minimum inhibitory concentrations (MICs) of HD-gal against bacteria will be investigated, and, in addition, cytotoxicity to human skin cells of HD-gal will be examined. It is expected that it will eventually be able to develop a new cosmetic preservative, which have low cytotoxicity against human skin cell and maintains antimicrobial effect.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1244-1248
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• 1998

Ozonolysis reactions of cyclic olefins 1a-c and norbomene In in the presence of trifluoroactophenone 6 provided the corresponding cross-ozonides 7a-c and 7n. Further reactions of ozonides 7a-c and 7n with the independently prepared carbonyl oxide 11 gave diozonides of structure l0a-c and 10n. The ozonolysis of 1methylcyclopentene 12a and 1-methylcyclohexene 12b in the presence of trifluoroactophenone 6 provided exclusively ozonide 15 and 16 derived from capture of carbonyl oxide 13. All of the new ozonides have been isolated as pure substances and characterized by their 1H NMR and 13C NMR spectra.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.255-263
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• 2016

Antimicrobial properties of Licorice(Glycyrrhizae radix L.) against food spoilage microorganism, Bacillus subtilis KCTC 1021 was investigated. Antibacterial activity of the essential oil was as equivalent as Potassium metabisulfite and myconazole. The licorice extracts was fractionated to hexane, chloroform, ethyl acetate, butanol and water fraction. Chloroform fraction showed the highest inhibitory effect on the Bacillus subtilis KCTC 1021. Chloroform fraction was further fractionated by silica gel column chromatography and thin layer chromatography(TLC). The antibacterial compound was isolated from their fractions and its chemical structures was identified as (R)-glabridin by ESI-MS, $^1H$-NMR and $^{13}C$-NMR.