JOURNAL OF FOOD SCIENCE
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2022
·Vol. 87
·期 9
·3953-3964
·
IF 3.693
Yuan Li,Cijian Li,Meiyu Chen,Zunying Liu,Mingyong Zeng,Yaqin Hu
Sous-vide cooking is a highly praised method used to cook muscle foods because of its desired effect of providing better sensory properties by maintaining texture. In this study, we further explored the effect of water on texture by revealing the mechanisms of moisture migration. Low field nuclear magnetic resonance (LF-NMR) showed that the nonflowing water in sous-vide cooking hairtail was 2.36 ± 0.33% higher than that in traditional cooking. Magnetic resonance imaging (MRI) was used to clarify the law of moisture migration induced by temperature, and the moisture migration of the sous-vide cooking hairtail was slower during the holding heating stage. The microstructure explained the change rules of the texture. The degree of change was consistent with the moisture migration level. Digitalizing analysis quantitatively verified the effect of sous-vide cooking on the hairtail microstructure. The low moisture migration rate of sous-vide cooking resulted in a less damaged microstructure of the hairtail, manifesting as a desirable texture. Practical Application LF-NMR and MRI showed that sous-vide hairtails exhibited a lower moisture migration rate. The holding heating stage only slightly changed the microstructure of the hairtail. The digitalizing analysis confirmed the moisture migration mechanisms. Heat-induced protein denaturation was closely related to the water state.
研究领域:
食品科学
·
生物物理学
✓ 已验证
DOI
高影响因子
TALANTA
·
2017
·
IF 4.162
Ting Li,Yong Liao,Xiaoyan Jiang,Di Mu,Xiandeng Hou,Chunchun Zhang,Pengchi Deng
The chemical shifts of several important endogenous phosphorus compounds under different pH conditions were explored, including adenosine-5′-triphosphate, adenosine-5′-diphosphate, adenosine-5′-monophosphate, phosphorylcholine and phosphorylethanolamine. Their 31 P NMR and 1 H NMR chemical shifts were all pH-sensitive in the similar pH range. Two dimensional (2D) 1 H– 31 P NMR spectra were found helpful to identify these endogenous phosphorus markers in biological samples from rather complicated NMR spectra. Herein, for the first time, a pH sensor based on 2D 1 H– 31 P NMR was established and applied to biological samples analysis with pH values determined in good agreement with those by potentiometric method . Apart from being simple, green, rapid and less sample-consuming, information concerning both the endogenous phosphorus markers and pH status could be attained in a single NMR run, which demonstrated the great potential of this method in rare sample analysis and even disease diagnosis.
研究领域:
生物化学
·
医学诊断
✓ 已验证
DOI
PubMed
高影响因子
Journal of the American Chemical Society
·
2017
·
IF 13.858
Fen Liu,Ningdong Feng,Qiang Wang,Jun Xu,Guodong Qi,Chao Wang,Feng Deng
The detailed structure–activity relationship of surface hydroxyl groups (Ti–OH) and adsorbed water (H2O) on the TiO2 surface should be the key to clarifying the photogenerated hole (h+) transfer mechanism for photocatalytic water splitting, which however is still not well understood. Herein, one- and two-dimensional 1H solid-state NMR techniques were employed to identify surface hydroxyl groups and adsorbed water molecules as well as their spatial proximity/interaction in TiO2 photocatalysts. It was found that although the two different types of Ti–OH (bridging hydroxyl (OHB) and terminal hydroxyl (OHT) groups were present on the TiO2 surface, only the former is in close spatial proximity to adsorbed H2O, forming hydrated OHB. In situ 1H and 13C NMR studies of the photocatalytic reaction on TiO2 with different Ti–OH groups and different H2O loadings illustrated that the enhanced activity was closely correlated to the amount of hydrated OHB groups. To gain insight into the role of hydrated OHB groups in the h+ transfer process, in situ ESR experiments were performed on TiO2 with variable H2O loading, which revealed that the hydrated OHB groups offer a channel for the transfer of photogenerated holes in the photocatalytic reaction, and the adsorbed H2O could have a synergistic effect with the neighboring OHB group to facilitate the formation and evolution of active paramagnetic intermediates. On the basis of experimental observations, the detailed photocatalytic mechanism of water splitting on the surface of TiO2 was proposed.
研究领域:
材料科学
·
催化化学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2018
·
IF 3.129
Shasha Cheng,Tan Zhang,Xiaohui Wang,Yukun Song,Huihui Wang,Haitao Wang,Peiqiang Yang,Mingqian Tan
Water and lipid changes play important roles for the quality formation of salted duck eggs . In the present study, low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) were introduced to monitor water and lipid dynamics of duck egg during salting as nondestructive methods . Four proton pools with different mobilities in fresh duck egg matrix were identified by LF-NMR transverse relaxation, and salting significantly changed the proton mobility due to the gelation of egg yolk, release of lipid and watery of egg white . MRI showed high density of proton with lower mobility and higher mobility in egg yolk and white, respectively, and the brighter region of egg yolk in T 1 images continuously decreased from vitelline membrane to center. The variations in the relaxation parameters and MRI images have a close relationship with other quality characteristics of duck eggs induced by salt. Therefore, LF-NMR and MRI could provide information about water and lipid dynamics of duck eggs during salting, and have great potential for quality assurance in salted duck eggs as a fast and non-destructive method.
研究领域:
食品科学
·
生物物理学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Xinxi Zeng,Bingcheng Luo,Han Zhang,Xiaoqing Xi,Bo Li,Ji Zhou
Electric field-induced antiferromagnets with ultrahigh resonant frequencies without current flow in insulating materials is highly desired. This paper reports the terahertz (THz) responses of Γ 4 in rare-earth orthoferrite GdFeO 3 ceramics, which were manipulated using thickening and thermal methods. As the thickness was increased, the noise was greatly reduced, and increased peak heights of both the ferromagnetic resonances and antiferromagnetic resonances were observed. For the thermal control of THz responses in GdFeO 3 , the resonant frequencies of both the ferromagnetic resonances and antiferromagnetic resonances experienced a blue shift , and their peak heights increased. The detected shifts of the responses were determined by the changes in thermodynamic potential . Moreover, macroscopic properties were collected to verify the coexistence of ferromagnetism and antiferromagnetism .
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
TALANTA
·
2015
·
IF 3.545
Yakun Lian,Hua Jiang,Jinzhou Feng,Xiaoyan Wang,Xiandeng Hou,Pengchi Deng
ATP , ADP and AMP are energy substances with vital biological significance. Based on the structural differences, a simple, rapid and comprehensive method has been established by 1 H and 31 P Nuclear Magnetic Resonance ( 1 H-NMR and 31 P-NMR) spectroscopies. Sodium 3-(trimethylsilyl) propionate-2,2,3,3-d 4 (TMSP) and anhydrous disodium hydrogen phosphate (Na 2 HPO 4 ) were selected as internal standards for 1 H-NMR and 31 P-NMR, respectively. Those three compounds and corresponding internal standards can be easily distinguished both by 1 H-NMR and 31 P-NMR. In addition, they all have perfect linearity in a certain range: 0.1–100 mM for 1 H-NMR and 1–75 mM for 31 P-NMR. To validate the precision of this method, mixed samples of different concentrations were measured. Recovery experiments were conducted in serum (91–113% by 1 H-NMR and 89–113% by 31 P-NMR).
研究领域:
生物化学
·
医学检测
✓ 已验证
DOI
PubMed
高影响因子
Industrial Chemistry & Materials
·
2022
·Vol. 1
·期 2
·240-246
·
IF 0
Hui Cao,Mengyu Dou,Zexiang Lyu,Yingxiong Wang,Christian Marcus Pedersen,Yan Qiao
Carbazole and anthracene, two aromatic hydrocarbon components contained in coal tar, are used as essential organic intermediates to synthesize various carbazole derivatives and anthraquinones. N,N-Dimethylformamide (DMF) is a commonly used solvent to extract carbazole from crude mixtures of carbazole and anthracene. However, the interaction between carbazole/anthracene and DMF in the extraction process is still to be fully understood at the molecular level. In this work, the intermolecular interaction of carbazole/anthracene with DMF was investigated using various NMR techniques, including 1H NMR titration, variable temperature NMR spectroscopy (VT-NMR), Nuclear Overhauser Effect Spectroscopy (NOESY), and diffusion-ordered spectroscopy (DOSY). The observed 1H chemical shift changes of carbazole indicated strong intermolecular hydrogen bonds between carbazole and DMF, which was further supported by the decrease in the molecular self-diffusion coefficients (D) of both carbazole and DMF according to DOSY measurements. Moreover, NOESY experiments revealed that the distance between the aldehydic hydrogen of DMF and the N–H of carbazole was smaller than 5 Å. Accordingly, an intermolecular hydrogen bond between carbazole and DMF in the form of CO⋯H–N was proposed. This research increases our knowledge about the separation process of carbazole and anthracene and hence helps improve the methods.
Keywords: NMR; Carbazole; Separation; Intermolecular hydrogen bonds.
研究领域:
化学
·
有机化学
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分析化学
✓ 已验证
DOI
Foods
·
2021
·Vol. 10
·期 8
·1755
·
IF 4.35
Zhili Sheng,Junmei Liu,Bao Yang
Astragalus membranaceusis a functional food with multiple bioactivities. It presents differentiated health benefits due to origins. Polysaccharides (APS) are the leading bioactive macromolecules ofA. membranaceus, which are highly related to its health benefits. However, the effect of origin on the structural characteristics of APSs remains unclear. In this work, polysaccharides from four origins were isolated and identified by NMR. The results showed APSs of four origins had identical monosaccharide composition and glycosidic linkage. Rhamnogalacturonan II pectins and α-(1→4)-glucan were the dominant polysaccharides. However, the level of methyl ester in pectins varied to a large extent. The molecular weight profiles of APSs were also different. Inner Mongolia APS had the largest percentage of 20–40 kDa polysaccharides. Molecular weight and methyl ester level were two important parameters determining the difference of APSs from four origins. These results were helpful to recognize the origin-related quality ofA. membranaceus.Keywords:glycosidic linkage;monosaccharide composition;NMR;pectin
研究领域:
植物学
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食品科学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Contrast Media & Molecular Imaging
·
2018
·
IF 2.934
Weiyue Li,Xiang Xiao,Xiaodan Li,Yikai Xu,Lichao Ma,Liuji Guo,Chenggong Yan,Yuankui Wu
Objective. To investigate the potential of L5 peptide-guided pretargeting approach to identify GPC3-expressing hepatocellular carcinoma (HCC) using ultrasmall superparamagnetic iron oxide (USPIO) as the MR probe. Methods. Immunofluorescence with carboxyfluorescein- (FAM-) labeled L5 peptide was performed in HepG2 cells. Polyethylene glycol-modified USPIO (PEG-USPIO) and its conjugation with streptavidin (SA-PEG-USPIO) were synthesized, and their hydrodynamic diameters, zeta potential, T2 relaxivity, and cytotoxicity were measured. In vitro and in vivo two-step pretargeting MR imaging was performed on HepG2 cells and tumor-bearing mice after the administration of biotinylated L5 peptide (first step), followed by SA-PEG-USPIO (second step). Prussian blue staining was performed to assess iron deposition in tumors. Results. The high specificity of L5 peptide for GPC3 was demonstrated. Generation of SA-PEG-USPIO nanoparticles with good biocompatibility (an average hydrodynamic diameter of 35.97 nm and a zeta potential of −7.91 mV), superparamagnetism (R2 = 0.1039 × 103 mM−1s−1), and low toxicity was achieved. The pretargeting group showed more enhancement than the nonpretargeting group both in vitro (60% vs 20%, ) and in vivo (32% vs 6%, ). Substantial iron deposition was only observed in HepG2 cells and tumors in the pretargeting group. Conclusion. L5 peptide-guided, two-step pretargeting approach with USPIO as the MR imaging probe is a lucrative strategy to specifically identify GPC3-expressing HCC.
研究领域:
医学影像学
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 28
·期 1
·1052-1060
·
IF 3.056
Sun Xu,Xu Li,Jiang Weina,Xuan Yan,Lu Wen,Li Zhong,Yang Shilong,Gu Zhenzhen
In the present study, a magnetic adsorbent, rhein-coated magnetic Fe 3 O 4 nanoparticle (RMNP), for Pb 2+ and Mg 2+ had been developed, and adsorption mechanism was studied via low-field NMR. RMNP was characterized by TEM, FTIR, and XRD. RMNP could adsorb and remove Pb 2+ and Mg 2+ from water and was successfully applied to remove Pb 2+ and Mg 2+ from wastewater, with satisfactory recovery rates and high adsorption capacities. The calculated maximum adsorption capacity for Mg 2+ and Pb 2+ was approximately 69.3 and 64.9 mg g −1 of RMNP, respectively, which was better than some results reported. Low-field NMR results showed that Pb 2+ or Mg 2+ enhanced the T 2 relaxation time of RMNP, which suggested that RMNP selectively coordinated with Pb 2+ or Mg 2+ and led to the aggregation of RMNP, furthermore removal of Pb 2+ or Mg 2+ from water. The standard curves for △T 2 -cation concentration exhibited good line correlation. The linear ranges were from 4.2 × 10 −6 to 2.0 × 10 −4 mol L −1 for Pb 2+ and from 5.0 × 10 −6 mol L −1 to 1.0 × 10 −4 mol L −1 for Mg 2+ , respectively. The limits of detection were 1.4 × 10 −6 mol L −1 for Pb 2+ and 2.1 × 10 −6 mol L −1 for Mg 2+ , respectively. In short, low-field NMR could clearly display the interaction between RMNP and Pb 2+ or Mg 2+ , even be used to detect Pb 2+ or Mg 2+ in suitable condition. Besides, this method could be expanded to study the interaction between other magnetic adsorbents and analytes.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Revista Brasileira de Farmacognosia-Brazilian Journal of Pharmacognosy
·
2020
·Vol. 30
·期 1
·28-33
·
IF 1.407
Wang Cong,Zhang Pengpeng,Zhang Xiuli,Yu Mingming,Lv Zhihua
Huganning, a Chinese patent medicine, has been used in clinical practice for the treatment of hepatitis in China for more than 20 years, and its main physiologically active components are polydatin and emodin. In this study, a rapid and accurate proton nuclear magnetic resonance method for the quantification of these constituents was developed. 4-Nitrochlorobenzene was selected as an internal standard, and the signals for polydatin at δ 6.44 ppm and emodin at δ 7.54 ppm were chosen for the quantification. Validation of the method was performed in terms of specificity, precision, and stability. The results indicated that the method was precise and in line with the China Food and Drug Administration guidance. The method has been successfully applied to characterize tablets and capsules obtained from six pharmaceutical companies. This study indicated that the rapid 1 H NMR method is more suitable for the quality control of Huganning than the high-performance liquid chromatography method.
Graphical Abstract
研究领域:
药学
·
中药学
✓ 已验证
DOI
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Hui Ma,Christian Marcus Pedersen,Qi Zhao,Zexiang Lyu,Hui Chang,Yan Qiao,Xianglin Hou,Yingxiong Wang
The Fischer–Tropsch (FT) process is a practical approach to convert synthesis gas (CO and H 2 ) into hydrocarbons and oxygenates, and these product mixtures are usually well-characterized. However, the analysis of Fischer–Tropsch waste water (FTW) is still somewhat underdeveloped and the exact composition of FTW remains unclear. Herein, various qualitative NMR techniques, especially diffusion-ordered spectroscopy (DOSY) and one dimension (1D) selective gradient total correlation spectroscopy (SelTOCSY) were strategically applied in the analysis of FTW. The NMR results show that the DOSY technique can pseudo-separate most of components in complex mixtures over the diffusion dimension. The SelTOCSY technique is used as a supporting method in the cases where the DOSY technique cannot clearly distinguish overlapped signals. Moreover, the quantitative 1 H NMR (qNMR) was further used to quantify the components of the sample. These routine and advanced qualitative and quantitative NMR technique utilized here provide a fast, effective and feasible method for the identification of complex mixtures in FTW, which might be a powerful and fast alternative to gas chromatography or high performance liquid chromatography for FTW research.
研究领域:
化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）