• 제목/요약/키워드: Nuclear magnetic resonance (NMR) spectroscopy

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우르소데옥시콜린산 및 케노데옥시콜린산의 베타시클로덱스트린 포접복합체의 물리화학적 특성비교 (Comparison of Physicochemical Properties between Ursodeoxycholic Acid and Chenodeoxycholic Acid Inclusion Complexes with ${\beta}-Cyclodextrin$)

  • 이승룡;정연복;한건;신재영
    • 약학회지
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    • 제38권3호
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    • pp.300-310
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    • 1994
  • Physicochemical properties for the inclusion complex of chenodeoxycholic acid(CDCA) and it's $7{\beta}-hydroxy$ epimer ursodeoxycholic acid(UDCA) with ${\beta}-cyclodextrin({\beta}-CyD)$ were studied. The formation of the complex in the solid state were confimed by polarized microscopy and differential scanning calorimetry(DSC). Proton nuclear magnetic resonance$(^1H-NMR)$spectroscopy showed that CDCA and UDCA form an inclusion complex with ${\beta}-CyD$ in aqueous solution. The 1 : 1 stoichiometry of the complex was dextermined by the continuous variation method. From DSC and $^1H-NMR$ studies, there were not any differences between CDCA and UDCA. Complex of CDCA and UDCA showed increase in solubility and dissolution compared with CDCA and UDCA alone, respectively. Solubility pattern of UDCA complex was pH independent but, CDCA complex was like that of CDCA. Dissolution rate increased markedly in case of UDCA complex compared with CDCA complex, especially in acidic pH value.

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Effect of [Al(DMSO2)3]3+ Concentration on Al Electrodeposition from AlCl3/Dimethylsulfone Baths

  • Kim, Sangjae;Matsunaga, Naoya;Kuroda, Kensuke;Okido, Masazumi
    • Journal of Electrochemical Science and Technology
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    • 제9권1호
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    • pp.69-77
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    • 2018
  • Aluminum electrodeposition was carried out in dimethylsulfone ($DMSO_2$) baths containing 6.2-28.3 mol% $AlCl_3$ at 403 K. The electrochemically active species for Al electrodeposition in $DMSO_2$ baths were investigated. Electrochemical behavior of the electrolyte and the deposition mechanism were studied via cyclic voltammetry (CV). Properties of the deposits were assessed by scanning electron microscopy with energy-dispersive X-ray spectroscopy and X-ray diffraction. In addition, structures of the ionic complexes formed with aluminum in the bath were characterized by $^{27}Al$ nuclear magnetic resonance (NMR) spectroscopy. NMR spectra revealed that all baths contained two ionic species: $AlCl_4{^-}$ and $[Al(DMSO_2)_3]^{3+}$. Al electrodeposited when the $[Al(DMSO_2)_3]^{3+}$ concentration was the highest (23.3 mol% $AlCl_3$) exhibited fine grain sizes, relatively smooth surfaces, and high purities.

Identification of Loliolide with Anti-Aging Properties from Scenedesmus deserticola JD052

  • Dae-Hyun Cho;Jin-Ho Yun;Jina Heo;In-Kyoung Lee;Yong-Jae Lee;Seunghee Bae;Bong-Sik Yun;Hee-Sik Kim
    • Journal of Microbiology and Biotechnology
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    • 제33권9호
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    • pp.1250-1256
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    • 2023
  • Herein, different extracts of Scenedesmus deserticola JD052, a green microalga, were evaluated in vitro as a potential anti-aging bioagent. Although post-treatment of microalgal culture with either UV irradiation or high light illumination did not lead to a substantial difference in the effectiveness of microalgal extracts as a potential anti-UV agent, the results indicated the presence of a highly potent compound in ethyl acetate extract with more than 20% increase in the cellular viability of normal human dermal fibroblasts (nHDFs) compared with the negative control amended with DMSO. The subsequent fractionation of the ethyl acetate extract led to two bioactive fractions with high anti-UV property; one of the fractions was further separated down to a single compound. While electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy analysis identified this single compound as loliolide, its identification has been rarely reported in microalgae previously, prompting thorough systematic investigations into this novel compound for the nascent microalgal industry.

Basic Principles of MR

  • 김성은
    • 대한자기공명의과학회:학술대회논문집
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    • 대한자기공명의과학회 1999년도 춘계학술대회 제3차 심포지움
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    • pp.1-9
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    • 1999
  • 핵자기 공명(NMR:nuclear magnetic resonance)은 19451건 Bloch, Procell등에 의해 처음으로 실험적으로 입증된 후에 생화학 및 약학 분야에서 분자단위의 물질의 성분, 구조, 대사물질의 역학적 운동 및 상태에 관한 정보를 아는데 유용한 기법으로 사용 되어 왔다. 의학분야에서는 Lauterber등에 의해 자기공명영상볍(Magnetic Resonance Imaging:MRI)으로 개발되어 질병의 진단 및 치료에 많은 공헌을 하게되었다. 해부학적영상 뿐 아니라 분석방법으로 병변 부위 및 인체 기관에서의 각종 대사물질의 정량적인 양과 변화를 알 수 있는 자기공명분광기법(magnetic resonance spectroscopy:MRS)도 활발한 임상적용이 이루어지고 있다. 자기공명영상법의 활발한 임상적 응용 및 새로운 technique이해를 위해서는 물리학적 개념(MR Physics)을 이해하는 것이 매우 중요하다.

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Metabolomics comparison of serum and urine in dairy cattle using proton nuclear magnetic resonance spectroscopy

  • Eom, Jun Sik;Kim, Eun Tae;Kim, Hyun Sang;Choi, You Young;Lee, Shin Ja;Lee, Sang Suk;Kim, Seon Ho;Lee, Sung Sill
    • Animal Bioscience
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    • 제34권12호
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    • pp.1930-1939
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    • 2021
  • Objective: The aim of the study was to conduct metabolic profiling of dairy cattle serum and urine using proton nuclear magnetic resonance (1H-NMR) spectroscopy and to compare the results obtained with those of other dairy cattle herds worldwide so as to provide a basic dataset to facilitate research on metabolites in serum and urine. Methods: Six dairy cattle were used in this study; all animals were fed the same diet, which was composed of total mixed ration; the fed amounts were based on voluntary intake. Blood from the jugular neck vein of each steer was collected at the same time using a separate serum tube. Urine samples were collected by hand sweeping the perineum. The metabolites were determined by 1H-NMR spectroscopy, and the obtained data were statistically analyzed by performing principal component analysis, partial least squares-discriminant analysis, variable importance in projection scores, and metabolic pathway data using Metaboanalyst 4.0. Results: The total number of metabolites in the serum and urine was measured to be 115 and 193, respectively, of which 47 and 81, respectively were quantified. Lactate (classified as an organic acid) and urea (classified as an aliphatic acylic compound) exhibited the highest concentrations in serum and urine, respectively. Some metabolites that have been associated with diseases such as ketosis, bovine respiratory disease, and metritis, and metabolites associated with heat stress were also found in the serum and urine samples. Conclusion: The metabolites measured in the serum and urine could potentially be used to detect diseases and heat stress in dairy cattle. The results could also be useful for metabolomic research on the serum and urine of ruminants in Korea.

Metabolomics comparison of rumen fluid and milk in dairy cattle using proton nuclear magnetic resonance spectroscopy

  • Eom, Jun Sik;Kim, Eun Tae;Kim, Hyun Sang;Choi, You Young;Lee, Shin Ja;Lee, Sang Suk;Kim, Seon Ho;Lee, Sung Sill
    • Animal Bioscience
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    • 제34권2호
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    • pp.213-222
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    • 2021
  • Objective: The metabolites that constitute the rumen fluid and milk in dairy cattle were analyzed using proton nuclear magnetic resonance (1H-NMR) spectroscopy and compared with the results obtain for other dairy cattle herds worldwide. The aim was to provide basic dataset for facilitating research on metabolites in rumen fluid and milk. Methods: Six dairy cattle were used in this study. Rumen fluid was collected using a stomach tube, and milk was collected using a pipeline milking system. The metabolites were determined by 1H-NMR spectroscopy, and the obtained data were statistically analyzed by principal component analysis, partial least squares discriminant analysis, variable importance in projection scores, and metabolic pathway data using Metaboanalyst 4.0. Results: The total numbers of metabolites in rumen fluid and milk were measured to be 186 and 184, and quantified as 72 and 109, respectively. Organic acid and carbohydrate metabolites exhibited the highest concentrations in rumen fluid and milk, respectively. Some metabolites that have been associated with metabolic diseases (acidosis and ketosis) in cows were identified in rumen fluid, and metabolites associated with ketosis, somatic cell production, and coagulation properties were identified in milk. Conclusion: The metabolites measured in rumen fluid and milk could potentially be used to detect metabolic diseases and evaluate milk quality. The results could also be useful for metabolomic research on the biofluids of ruminants in Korea, while facilitating their metabolic research.

1H, 15N, and 13C Resonance Assignments of the Anti-CRISPR AcrIIA4 from Listeria monocytogenes Prophages

  • Kim, Iktae;Kim, Nak-Kyoon;Suh, Jeong-Yong
    • 한국자기공명학회논문지
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    • 제22권3호
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    • pp.71-75
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    • 2018
  • The CRISPR-Cas system is the adaptive immune system in bacteria and archaea against invading phages or foreign plasmids. In the type II CRISPR-Cas system, an endonuclease Cas9 cleaves DNA targets of phages as directed by guide RNA comprising crRNA and tracrRNA. To avoid targeting and destruction by Cas9, phages employ anti-CRISPR (Acr) proteins that act against host bacterial immunity by inactivating the CRISPR-Cas system. Here we report the backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments of AcrIIA4 that inhibits endonuclease activity of type II-A Listeria monocytogenes Cas9 and also Streptococcus pyogenesis Cas9 using triple resonance nuclear magnetic resonance spectroscopy. The secondary structures of AcrIIA4 predicted by the backbone chemical shifts show an ${\alpha}{\beta}{\beta}{\beta}{\alpha}{\alpha}$ fold, which is used to determine the solution structure.

Complexation between Venlafaxine Hydrochloride and β -Cyclodextrin:Structural Study by Nuclear Magnetic Resonance Spectroscopy

  • Ali, Syed Mashhood;Koketsu, Mamoru;Asmat, Fahmeena
    • Bulletin of the Korean Chemical Society
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    • 제27권9호
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    • pp.1397-1400
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    • 2006
  • A detailed spectroscopic study ($^1H$ NMR, COSY, ROESY) of complexation of venlafaxine hydrochloride (VEN) with $\beta$-cyclodextrin ($\beta$--CD) was carried out in solution. The stoichiometry of the complex was determined to be 1 : 1 and penetration of aromatic ring into $\beta$-Cyclodextrin cavity was confirmed from primary rim side, with the help of ROESY spectral data. The structure of the venlafaxine hydrochloride-$\beta$-CD complex has been proposed. The association constant was determined to be 234 $M^{-1}$.

폴리에틸렌테레프탈레이트-코-에틸렌이소프탈레이트의 고리해중합 (Cyclo-depolymerization of Poly (ethylene Terephthalate-co-ethylene Isophthalate)s)

  • Yoo, Dong-Il;Lee, Eung-Eui;Shin, Youn-Sook
    • 한국염색가공학회지
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    • 제10권1호
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    • pp.20-24
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    • 1998
  • Oligomeric extracts of poly(ethylene terephthalate-co-ethylene isophthalate)s [(PET/EI] are analyzed by high performance liquid chromatography(HPLC) and nuclear magnetic resonance spectroscopy (NMR). Existence of separated peaks for small cyclics of trimer and tetramer gives the existence of structural isomeric forms. NMR confirms that cyclization of PET/EI occurs more easily at the site of isophthaloyl unit.

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Comparison of metabolic profiling of Daphnia magna between HR-MAS NMR and solution NMR techniques

  • Kim, Seonghye;Lee, Sujin;Lee, Wonho;Lee, Yujin;Choi, Juyoung;Lee, Hani;Li, Youzhen;Ha, Seulbin;Kim, Suhkmann
    • 한국자기공명학회논문지
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    • 제25권2호
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    • pp.12-16
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    • 2021
  • Daphnia magna is used as target organism for environmental metabolomics. The metabolome of D. magna was studied with NMR spectroscopy. Most studies used the extract of D. magna, but the reproducibility cannot be obtained using extracted sample. In this study, lyophilized D. magna samples were analyzed with two different 1H NMR techniques, HR-MAS on intact tissues and solution NMR on extracted tissues. Samples were measured three times using 600 MHz NMR spectrometer. Metabolite extraction required more than twice as many D. magna, but the metabolite intensity was lower in solution NMR. In the spectra of HR-MAS NMR, the lipid signal was observed, but they did not interfere with metabolite profiling. We also confirmed the effect of swelling time on signal intensities of metabolites in HR-MAS NMR, and the results suggest that appropriate swelling should be used in lyophilized D. magna to improve the accuracy of metabolite profiles.