• 한국식품과학회지
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• 제31권5호
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• pp.1386-1391
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• 1999

치자(Gardenia jasminoides Ellis) 열매의 methanol추출물은 Gram양성 세균, Gram음성 세균, 효모 등의 미생물에 대하여 항미생물 활성을 보여, solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, ODS column chromatography, HPLC등에 의해 얻어진 활성 물질을 MS, GC-MS, $^{1}H-NMR,\;^{13}C-NMR$ 그리고 2D-NMR 등의 기기 분석에 의해 3,4-dihydroxybenzoic acid는 동정하였다. 치자 열매에서 3,4-dihydroxybenzoic acid가 항미생물 활성물질로 분리 동정된 것은 처음으로 생각된다. 3,4-dihydroxybenzoic acid는 건조 치자열매에 g당 $32.7\;{\mu}g$ 정도 함유되어 있었다.

• 한국축산식품학회지
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• 제41권2호
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• pp.312-323
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• 2021

The purpose of this study was to use 1H nuclear magnetic resonance (1H NMR) to quantify taste-active and bioactive compounds in chicken breasts and thighs from Korean native chicken (KNC) [newly developed KNCs (KNC-A, -C, and -D) and commercial KNC-H] and white-semi broiler (WSB) used in Samgye. Further, each breed was differentiated using multivariate analyses, including a machine learning algorithm designed to use metabolic information from each type of chicken obtained using 1H-13C heteronuclear single quantum coherence (2D NMR). Breast meat from KNC-D chickens were superior to those of conventional KNC-H and WSB chickens in terms of both taste-active and bioactive compounds. In the multivariate analysis, meat portions (breast and thigh) and chicken breeds (KNCs and WSB) could be clearly distinguished based on the outcomes of the principal component analysis and partial least square-discriminant analysis (R2=0.945; Q2=0.901). Based on this, we determined the receiver operating characteristic (ROC) curve for each of these components. AUC analysis identified 10 features which could be consistently applied to distinguish between all KNCs and WSB chickens in both breast (0.988) and thigh (1.000) meat without error. Here, both 1H NMR and 2D NMR could successfully quantify various target metabolites which could be used to distinguish between different chicken breeds based on their metabolic profile.

• Archives of Pharmacal Research
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• 제12권1호
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• pp.58-61
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• 1989

Studies of selectivity of hydrogen bond formation in chiral solute-solvent systems have been performed by $^1H\;and\;^{13}C$ nuclear magnetic resonance techniques. These data are correlated with the results of gas chromatographic investigations of the same systems. Interactions between the optically active solvent(N-(N-benzoyl-L-amino acid)-anilide) and optically active solute (N-trifluoroacetyl -L-alanyl isopropyl ester) were examined. NMR evidence indicated that hydrogen bonding interaction occurred between two N-H portion and on peptidyl carbonyl portion in stationary phase and solute molecule on three points. The association constants of solvent-solute interaction were calculated and the structure of the diastereomeric association complex between N-(N-benzoyl-L-valyl)-anilide and N-TFA-L-alanyl isopropyl ester was proposed.

• Asian Journal of Atmospheric Environment
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• 제12권2호
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• pp.153-164
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• 2018

We measured $^1H$ and $^{13}C$ nuclear magnetic resonance (NMR) spectra of Humic-like substances (HULIS) in urban atmospheric aerosols isolated by diethylaminoethyl (DEAE) and hydrophilic-lipophilic balance (HLB) resin to characterize their chemical structure. HULIS isolated by DEAE resin were characterized by relatively high contents of aromatic protons and relatively low contents of aliphatic protons in comparison with HULIS isolated by HLB resin, while the contents of protons bound to oxygenated aliphatic carbon atoms were similar. These results were consistent with the results of the $^{13}C$ NMR analysis and indicate that hydrophobic components were more selectively adsorbed onto HLB, while DEAE resins selectively retained aromatic carboxylic acids. Furthermore, we demonstrated that the chemical structural features of HULIS were significantly different between spring and summer samples and that these disparities were reflective of their different sources. The estimated concentrations of HULIS in spring were found to be regulated by vehicle emissions and pollen dispersion, while the behavior of HULIS in summer was similar to photochemical oxidant and nitrogen dioxide concentrations. The proportion of aliphatic protons for summer samples was higher than that for spring samples, while the proportion of aromatic protons for summer samples was lower than that for spring samples. These seasonal changes of the chemical structure may also involve in their functional expression in the atmosphere.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.54-68
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• 2011

$^1H$ nuclear magnetic resonance (NMR) spectroscopy of biological samples has been proven to be an effective and nondestructive approach to probe drug toxicity within an organism. In this study, ketoprofen toxicity was investigated using $^1H$-NMR spectroscopy coupled with multivariate statistical analysis. Histopathologic test of ketoprofen-induced acute gastrointestinal damage in rats demonstrated a significant dose-dependent effect. Furthermore, principal component analysis (PCA) derived from $^1H$-NMR spectra of urinary samples showed clear separation between the vehicle-treated control and ketoprofen-treated groups. Moreover, PCA derived from endogenous metabolite concentrations through targeted profiling revealed a dose-dependent metabolic shift between the vehicle-treated control, low-dose ketoprofen-treated (10 mg/kg body weight), and high-dose ketoprofen-treated (50 mg/kg) groups coinciding with their gastric damage scores after ketoprofen administration. The resultant metabolic profiles demonstrated that the ketoprofen-induced gastric damage exhibited energy metabolism perturbations that increased urinary levels of citrate, cis-aconitate, succinate, and phosphocreatine. In addition, ketoprofen administration induced an enhancement of xenobiotic activity in fatty oxidation, which caused increase levels of N-isovalerylglycine, adipate, phenylacetylglycine, dimethylamine, betaine, hippurate, 3-indoxylsulfate, N,N-dimethylglycine, trimethyl-N-oxide, and glycine. These findings demonstrate that $^1H$-NMR-based urinary metabolic profiling can be used for noninvasive and rapid way to diagnose adverse drug effects and is suitable for explaining the possible biological pathways perturbed by nonsteroidal anti-inflammatory drug toxicity.

• Journal of Biosystems Engineering
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• 제21권3호
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• pp.336-342
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• 1996

A 4.1MHz$1^H$ Nuclear Magnetic Resonance(NMR) sensor was designed and manufactured to evaluate the internal quality of fruits. The magnet console having 963gauss magnetic field induction was used for the NMR sensor. To optimize and evaluate the NMR sensor, glycerol and sugar-water solutions were used. $^1$H(proton) resonance signals were used to estimate the sugar contents in fruits. Artificial neural network models were developed to predict sugar contents in fruits from the proton resonance signals. The standard errors of prediction(SEP) were 0.565(apple), 0.394(pear) and 0.415(kiwi), respectively. The result implied that it was possible to evaluate apple, pear and kiwi into 3 grades using the NMR sensor.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.305-312
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• 1996

A 4.1MHz 1H Nuclear Magnetic Resonance (NMR) sensor was designed and manufactured to evaluate the internal quality of fruit. The magnet console having 963 gauss magnetic field induction was used for the NMR sensor. To optimize evaluate the NMR sensor, glycerol and sugar-water solutions were used. 1H(proton) resonance signals were use of to estimate the sugar contents in fruits the proton resonance signals and were validated . The standard errors of predictions(SEP) were 0.565(apple) , 0.394(pear) and 0.415(kiwi) respectively. The result implied that is possible to evaluate apple , pear and kiwi into 3 grades using the NMR sensor.

• Investigative Magnetic Resonance Imaging
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• 제12권2호
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• pp.107-114
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• 2008

목적 : 3T MR 기기를 이용하여, 췌장 주위에 발생한 낭성 종양에 대하여, 생체내, 그리고 생체외 생체내 자기공명분광법(magnetic resonance spectroscopy: MRS)를 획득한 후, 생체외 핵자기공명 (nuclear magnetic resonance, NMR) 스펙트럼을 기준으로 비교함으로써, 낭성 종양의 감별 진단에 있어 MRS의 적용 가능성을 알아보고자 하였다. 대상 및 방법 : 췌장 주위에 발행한 12예의 낭성 종양(점액성 낭성 종양=5, 췌담관내 유두종=5, 가성 낭종=1, 및 림프관종 n=1)을 대상으로 3.0T 생체내, 생체외 양성자 MRS 및 9T NMR 스펙트럼을 획득하였다. NMR의 피크와 상응하는 생체내, 생체외 양성자 MRS에서 관찰되는 피크의 존재유무를 알아보았으며, 특정 질환을 예측하는 피크에 대하여 알아보았다. 결과 : 생체내 MRS는 NMR과 민감도 29.6%, 특이도 82.6% 그리고, 67.7%의 정확도를 보였으며 (p=0.096, McNemar test), 생체외 MRS는 생체내 MRS는 민감도 57.1%, 특이도 92.6%, 그리고, 82.3%의 정확도를 보였다 (p = 0.362, McNemar test). 질병간의 스펙트럼의 차이는 NMR에서 췌담관내 유두종의 경우에서 점액성 낭성 종양에 비해 3.5-4.0 ppm에서 유의하게 많은 피크를 보였다 (p=0.026). 결론 : 결론적으로, NMR 이용한 화학물질 분석은 낭성 종양의 감별 진단에 도움이 될 가능성이 있는 기법으로 생각되지만, 생체내 및 생체외 MRS는 임상에 적용되기 위해서는 많은 기술적 발전을 필요로 하는 것으로 생각된다.

• Carbon letters
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• 제27권
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• pp.90-97
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• 2018

Electromagnetic interference (EMI) shielding is an important issue in modern daily life due to the increasing prevalence of electronic devices and their compact design. This study estimated EMI-shielding effect (EMI-SE) of small ($8-14{\times}17mm$) Hanji (Korean traditional paper) doped with carbon nanotubes (CNTs) and compared to Hanji without CNT using $^2H$ (92.1 MHz) and $^{23}Na$ (158.7 MHz) nuclear magnetic resonance (NMR) peak area data obtained from 1 M NaCl in $D_2O$ samples in capillary tubes that were wrapped in the Hanji samples. The simpler method of using the variation of reflected power and tuning frequency by inserting the sample into an NMR coil was also tested at 242.9, 158.7, and 92.1 MHz. Overall, EMI shielding was relatively more effective at the higher frequencies. Our results validated that NMR methods to be useful to evaluate EMI-SE, particularly for small, flexible shielding materials, and demonstrated that EMI shielding by absorption is dominant in Hanji mixed with CNT.

• 한국자기학회지
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• 제5권1호
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• pp.54-57
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• 1995

넓은 범위의 $^{1}H$ 핵자기공명 자기장에서 Heisenberg 반강자성체인 $MnCl_{2}.4H_{2}O$에 대하여 상온 수소 핵자기완화를 연구하였다. $MnCl_{2}.4H_{2}O$는 상온에서 밀접한 상자성 $Mn^{++}$ 이온계이지만 희박한 상자성계에서 예상되는 특성을 보인 반면에 희박한 상자성 근사와 매우 다른 결과도 보였다. 또한 수소 원자핵들은 0.7 T의 외부자기장 부근에서 스핀-격자 완화시간의 이상거동을 보였다.