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夏枯草属植物三萜类化学成分及13c nmr波谱特征

中国化学会第29届学术年会

作者：王耀鹏顾志荣孙宇靖王亚丽甘肃中医学院

本研究建立了基于13c nmr技术的不同生长年限当归指纹图谱,通过主成分分析(PcA)与模糊聚类分析(FcA)建立不同生长年限当归的鉴别与质量评价方法,为当归的分析提供参考。结果显示,13c nmr谱图上特征性较强的信号峰,即δ104、δ92、δ83、... 详细信息

本研究建立了基于13c nmr技术的不同生长年限当归指纹图谱,通过主成分分析(PcA)与模糊聚类分析(FcA)建立不同生长年限当归的鉴别与质量评价方法,为当归的分析提供参考。结果显示,13c nmr谱图上特征性较强的信号峰,即δ104、δ92、δ83、δ77、δ7075、δ63、δ62、δ56、δ40和δ19处可作为鉴别当归质量优劣的参考数据;PcA与FcA均能将27批不同生长年限当归样本完全分开,1年生与2年生当归13c nmr指纹图谱相似性强,但两者与3年生当归差异明显,阿魏酸、藁本内酯、3-正丁基苯酞以及部分糖类是引起不同生长年限当归指纹图谱差异的主要化学成分。说明所建立的13c nmr指纹图谱结合PcA和FcA可有效的用于不同生长年限当归的分类和质量评价。

关键词： 13c nmr 指纹图谱当归主成分分析模糊聚类分析

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夏枯草属植物三萜类化学成分及13C NMR波谱特征

Structural Elucidation of the Polymeric condensed Tannins of Acacia nilotica Subspecies by ^(13)c nmr, MALDI-TOF and TMA as Sources of Bioadhesives

作者：王祝举赵玉英陈雅妍马炳娜北京医科大学天然药物化学研究室

目的:对夏枯草属植物中三萜类化学成分研究进行综述,并对其c nmr波谱特征进行归纳总结。方法:查阅国内外研究文献,对夏枯草属植物中三萜类成分进行总结,并对其c nmr波谱特征进行归纳、分析。结果和结论:从夏枯草属植物中共分离得到了28... 详细信息

目的:对夏枯草属植物中三萜类化学成分研究进行综述,并对其c nmr波谱特征进行归纳总结。方法:查阅国内外研究文献,对夏枯草属植物中三萜类成分进行总结,并对其c nmr波谱特征进行归纳、分析。结果和结论:从夏枯草属植物中共分离得到了28个三萜类化合物,其中20个呈游离状态,8个呈结合状态(皂苷);且不同的三萜化合物其c nmr波谱在骨架类型、取代基类型及位置等方面均具有其特征性。

关键词：夏枯草三萜 13c nmr

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Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab Osman Antonio Pizzi Bertrand charrier Institute of Engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan ENSTIB-LERMAB University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and Engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°c tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13cnmr spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(Pc)and prodelphinidins(PD)in slightly different ***(56.5%Pc and 43.4%PD),Ant(57%Pc and 43%PD)and Ana(58%Pc and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOE at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13c nmr MALDI-ToF

Matrix Assisted Laser Desorption Ionization Time of Flight(MALDI-TOF)-Mass Spectrometry and^(13)c-nmr-Identified New compounds in Paraberlinia bifoliolata(Ekop-Beli)Bark Tannins

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Journal of Renewable Materials 2024年第3期12卷 553-568页

作者： Liliane Nga Benoit Ndiwe Achille Bernard Biwolé Antonio Pizzi Jean Jalin Eyinga Biwole Joseph Zobo Mfomo Laboratory of Forest Resources and Wood Valorization Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 1872DoualaCameroun Laboratory of Mechanics Training Unit in Engineering SciencesPost Graduate School of Fundamental and Applied SciencesUniversity of DoualaP.O.Box 2701DoualaCameroun Laboratory of Studies and Research on Wood Material(LERMAB) University of LorraineNancyFrance

Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial *** discovery of new tannins is therefore *** aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and carbon 13 Nuclear Magnetic Resonance(13c nmr).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica *** by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of *** are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic *** identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion *** information is reinforced by 13c nmr spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the *** analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.

关键词： Tannin Paraberlinia bifoliolata central African wood species MALDI-TOF/MS 13c nmr bark extracts thermomechanical behaviour wood-binder

Stereoselective synthesis of D-α-glucopyranosides,di-and tri-saccharides via 6-O-acetyl-glucopyranosyl bromides

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chinese Journal of chemistry 1995年第5期13卷 454-459页

作者： FEI, chang-Pei MA, YueInstitute of chemistry, chinese Academy of Science, Beijing 100080, chinacHAN, Tak-HangDepartment of chemistry, McGill University, Montreal, PQ, canada Institute of chemistry Chinese Academy of Science Beijing 100080 China Department of chemistry McGill University Montreal PQ Canada

Acetyl bromide cleaved 2,3,4-tri-O-benzyl-l,6-anhydro-B-D-glucopyranose (la) or 2,3,4-tri-O-benzyl-1,6-anhydro-B-Z)-galactopyranose (1a') to give the corresponding a-D-pyranosyl bromides (2). Reaction of 2 with ROH/diisopropylethylamine gave the corresponding a-glucopyra-nosides, di- and tri-saccharides with good yield. It was available to use 13c nmr to monitor the glycosidation reaction.

关键词： Stereoselection,α-D-pyranosyl bromide glycosidation 13c nmr

Electrochemical treatment of olive mill wastewater:Treatment extent and effluent phenolic compounds monitoring using some uncommon analytical tools

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Journal of Environmental Sciences 2013年第1期25卷 220-230页

作者： chokri Belaid Moncef Khadraoui Salma Mseddi Monem Kallel Boubaker Elleuch Jean Franois Fauvarque Laboratory of Water Energy and Environment Sfax UniversityENIS BP "1173" 3038 Sfax Tunisia Laboratory of Industrial Electrochemistry CNAM 2 Rue Conté 75003 Paris France

Problems related with industrials effluents can be divided in two parts：（1） their toxicity associated to their chemical content which should be removed before discharging the wastewater into the receptor media; （2） and the second part is linked to the difficulties of pollution characterisation and monitoring caused by the complexity of these matrixes. This investigation deals with these two aspects, an electrochemical treatment method of an olive mill wastewater （OMW） under platinized expanded titanium electrodes using a modified Gl＂ignard reactor for toxicity removal as well as the exploration of the use of some specific analytical tools to monitor effluent phenolic compounds elimination. The results showed that electrochemical oxidation is able to remove/mitigate the OMW pollution. Indeed, 87% of OMW color was removed and all aromatic compounds were disappeared from the solution by anodic oxidation. Moreover, 55% of the chemical oxygen demand （cOD） and the total organic carbon （TOc） were reduced. On the other hand, UV- Visible spectrophotometry, Gaz chromatography/mass spectrometry, cyclic voltammetry and 13c Nuclear Magnetic Resonance （nmr） showed that the used treatment seems efficaciously to eliminate phenolic compounds from OMW. It was concluded that electrochemical oxidation in a modified Grignard reactor is a promising process for the destruction of all phenolic compounds present in OMW. Among the monitoring analytical tools applied, cyclic voltammetry and 13c nmr are among the techniques that are introduced for the first time to control the advancement of the OMW treatment and gave a close insight on polyphenols disappearance.

关键词： olive mill wastewater electro-oxidation polyphenols cyclic voltammetry Gc/MS 13c nmr

Adsorption of cu(Ⅱ) on humic acids derived from different organic materials

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Journal of Integrative Agriculture 2015年第1期14卷 168-177页

作者： LI cui-lan JI Fan WANG Shuai ZHANG Jin-jing GAO Qiang WU Jing-gui ZHAO Lan-po WANG Li-chun ZHENG Li-rong college of Resource and Environmental Science Jilin Agricultural University Institute of Plant Science Jilin Agricultural Science and Technology College Institute of Agricultural Resources and Environments Jilin Academy of Agricultural Sciences Institute of High Energy Physics Chinese Academy of Sciences

The adsorption of cu（Ⅱ） from aqueous solution onto humic acid （HA） which was isolated from cattle manure （cHA）, peat （PHA）, and leaf litter （LHA） as a function of contact time, pH, ion strength, and initial concentration was studied using the batch method. X-ray absorption spectroscopy （XAS） was used to examine the coordination environment of the cu（ll） adsorbed by HA at a molecular level. Moreover, the chemical compositions of the isolated HA were characterized by elemental analysis and solid-state 13c nuclear magnetic resonance spectroscopy （nmr）. The kinetic data showed that the adsorption equilibrium can be achieved within 8 h. The adsorption kinetics followed the pseudo-second-order equation. The adsorption isotherms could be well fitted by the Langmuir model, and the maximum adsorption capacities of cu（ll） on cHA, PHA, and LHA were 229.4,210.4, and 197.7 mg g-1, respectively. The adsorption of cu（Ⅱ） on HA increased with the increase in pH from 2 to 7, and maintained a high level at pH〉7. The adsorption of cu（Ⅱ） was also strongly influenced by the low ionic strength of 0.01 to 0.2 mol L-1 NaNO3, but was weakly influenced by high ionic strength of 0.4 to 1 mol L-1 NaNO3. The cu（Ⅱ） adsorption on HA may be mainly attributed to ion exchange and surface complexation. XAS results revealed that the binding site and oxidation state of cu adsorbed on HA surface did not change at the initial cu（Ⅱ） concentrations of 15 to 40 mg L 1. For all the cu（Ⅱ） adsorption samples, each cu atom was surrounded by 40/N atoms at a bond distance of 1.95 A in the first coordination shell. The presence of the higher cu coordination shells proved that cu（Ⅱ） was adsorbed via an inner-sphere covalent bond onto the HA surface. Among the three HA samples, the adsorption capacity and affinity of cHA for cu（Ⅱ） was the greatest, followed by that of PHA and LHA. All the three HA samples exhibited similar types of elemental and functional groups, but different contents of elemental and functional gr

关键词： humic acid cu(Ⅱ) adsorption organic material 13c nmr XAS

Theoretical Study of 13c chemical Shifts Structures of Some ortho-Substituted 3-Anilino-2-nitrobenzo[b]thiophenes and 2-Anilino-3-nitrobenzo[b]thiophenes and comparison with Experimental

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chinese Journal of chemistry 2011年第2期29卷 237-242页

作者： Mahdi Rezaei Sameti Department of Physical chemistry Faculty of Science Malayer University Malayer 65157 Iran

13c nmr chemical shifts have been calculated for structures of some substituted 3-anilino-2-nitrobenzo- [b]thiophenes （2o） and 2-anilino-3-nitrobenzo[b]thiophenes （3o） derivatives containing OH, NH2, OMe, Me, Et, H, F, cl and Br. The molecular structures were fully optimized using B3LYP/6-31G（d,p）. The calculation of the 13c shielding tensors employed the GAUSSIAN 03 implementation of the gauge-including atomic orbital （GIAO） and continuous set of gauge transformations （cSGT） by using 6-311 ＋＋G（d,p） basis set at density functional levels of theories （DFT）. The isotropic and the anisotropy parameters of chemical shielding for all compounds are calculated. The predicted 13c chemical shifts are derived from equation δ=σ0＋σ where δ is the chemical shift, σ is the absolute shielding, and σ0 is the absolute shielding of the standard TMS. Excellent linear relationships have been observed between experimental and calculated 13c nmr chemical shifts for all derivatives.

关键词： DPT 13c nmr chemical shifts GIAO/cSGT

Biodegradable films of chitosan and tea polyphenols catalyzed by laccase and their physical and antioxidant activities

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Food Bioscience 2022年第2期46卷 158-163页

作者： Tong chen Yufei Shen Di Wu Rong Wu Jie Sheng Xiao Feng Xiaozhi Tang college of Food Science and Engineering Collaborative Innovation Center for Modern Grain Circulation and SafetyKey Laboratory of Grains and Oils Quality Control and ProcessingNanjing University of Finance and EconomicsNanjing210023China Hefei National Laboratory for Physical Sciences at the Microscale and Department of chemistry University of Science and Technology of China96 Jinzhai RoadHefeiAnhui230026China

The effects of laccase crosslinking chitosan(cS)and tea polyphenols(TP)on the structure,physical and antioxidant properties of cS-based biodegradable films were investigated in this *** crosslinking significantly increased the particle size and zeta-potential of cS+TP particles.A simple blending of cS and TP decreased the elongation at break significantly,while the elongation at break of biodegradable films significantly increased after laccase ***,TP addition increased the tensile strength(TS)of cS based films,while laccase crosslinking promoted the increase,making it more suitable for *** addition of TP significantly changed the cS-based films from white and transparent to light *** spectra showed that no c=N bond was observed in cS+TP particles,which could result from the inhibition of Schiff base reaction due to the big steric hindrance of *** shift of amide I peak to lower wavelength in laccase catalyzed films indicated the conversion of some primary amines into secondary amines caused by Michael addition *** was proposed that laccase oxidized polyphenol to o-quinones,which reacted with nucleophilic groups of chitosan,leading to the increase of secondary ***,the antioxidant capacity of cS+TP films crosslinked by laccase increased significantly compared with cS and cS+TP blended *** summary,laccase catalysis could be applied to manufacture biodegradable films with improved mechanical property and antioxidant activity.

关键词： Laccase crosslinking Physical properties FTIR Antioxidant properties 13c nmr