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2002年诺贝尔化学奖授予了在质谱和核磁共振领域有杰出贡献的三位科学家。Jonh B. Fenn和Koichi Tanaka发展了质谱鉴定生物大分子质量的方法,Kurt Wuethrich建立了核磁共振测定蛋白质分子溶液三维结构的方法。他们的研究成果是质谱和核磁共振方法发展的里程碑,极大地推动了这两种研究方法的进一步发展。如今,质谱和核磁共振已发展成为认识生物大分子的强劲的研究手段。 相似文献
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金顶侧耳化学成分的研究 总被引：2，自引：1，他引：2
对榆黄蘑的化学成分进行了研究,从子实体中分离和鉴定出D-甘露醇、麦角甾醇、1-癸醇、5-氧代-L-脯氨酸甲酯、5,10-二乙氧基-2,3,7,8-四氢化-1H,6H-联吡咯-[1,2-a;1 ,2 -d]吡嗪、邻苯二甲酸二丁酯和环戊-1,2-二酮等物质。并采用高效薄层析和高效液相色谱两种方法证明了洛伐他汀在金顶侧耳中的存在。 相似文献
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目的:获得快速检测发酵液中10 - DAB含量的方法.方法:以产10 - DAB内生真菌的发酵液为材料,比较TLC的三种展开系统:丙酮-石油醚、正己烷-氯仿-乙酸乙酯-甲醇-三乙胺和环己烷-乙酸乙酯,及成分的不同比例关系对10 - DAB展开效果的影响,再以HPLC进行检测验证.结果:先浓缩发酵液,再以丙酮:石油醚=4:1作为展开剂,乙醇:浓硫酸=9:1为显色剂,最小检测限为0.3μg.结论:该检测方法快速准确,为培育和改良产10 - DAB菌种以及发酵生产10 -DAB奠定基础. 相似文献
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在微生物资源的开发研究过程中,利用TLC方法,配合TLC数据库的检索,对嗜碱放线菌菌株YIMGQ14的次生代谢产物进行了研究。并从中分离纯化出两个具有生物活性的专利化合物“Umycin C”和“Umycin B”。结果证明：相对于常规的生物活性筛选,TLC法在微生物次生代谢产物研究中具有快速、简便、经济的特点,适合于小量常规筛选的目的。通过进一步对相关的TLC数据库进行构建和补充,将能极大地改善该方法的使用效率。 相似文献
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目的:在研究泽普油田产区菌株多态性的基础上,对石油降解功能菌株进行探讨。方法:通过稀释平板涂布法分离微生物;采用TLC和HPLC方法对分离菌株进行多糖成分鉴定,并进行16S rRNA和18S rRNA序列分析;采用溶血圈实验、排油圈法、石油黏度测定等方法,测定石油降解菌株降解能力。结果:分离菌株中有5株细菌和4株真菌,且菌株多糖的TLC分析结果与形态学鉴定结果基本相同;5株分离细菌中,2株细菌隶属于Bacillus属,3株细菌隶属于Enterobacter。另外4株真菌被鉴定为隶属于Penicillium属;分离菌株B2能降解石油。结论:泽普油田石油产区微生物的群落中存在一定丰度的细菌和真菌,含有B2的原油发酵液黏度为0.67±0.20 mPa.s.和原油在0.05水平上有显著性差异。推断B2对石油具有一定的降解能力。 相似文献
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柴胡类药材的柴胡皂甙分析 总被引：5，自引：0，他引：5
柴胡类药材的柴胡皂甙分析李光慧罗燕燕王瑛袁昌齐王年鹤（北京临床药学研究所,北京１０００３５）（江苏省中国科学院植物研究所,南京２１００１４）ＡｎａｌｙｓｉｓｏｆｓａｉｋｏｓａｐｏｎｉｎｓｉｎｍｅｄｉｃｉｎａｌＢｕｐｌｅｕｒｕｍｓｐｐ．ＬｉＧｕａｎｇ... 相似文献
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黄仁槐 《生物化学与生物物理进展》2002,29(6):973-976
2002年诺贝尔化学奖授予了质谱和核磁共振领域的三位科学家以表彰他们对生物大分子鉴定及结构分析方法做出的贡献．其中两位科学家J．B．Fenn和K．Tanaka分别发展了生物大分子质谱分析的软解吸电离方法;另一科学家K．Wüthrich则将核磁共振技术成功地应用于生物大分子如蛋白质的溶液三维结构测定．他们的研究成果已使质谱和核磁共振技术成为生物大分子强有力的研究手段,极大地促进了生物大分子的研究进程,必将对整个生命科学研究产生深远的影响． 相似文献
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利用紫色杆菌(Chromobacterium violaceum CV026)报告系统从粉纹夜蛾(Trichoplusia ni)中肠中分离出两株可以产群体感应信号分子的菌株Tni-9和Se-9。通过16S rDNA序列分析结果可知,分离菌株均与蒙氏肠球菌(Enterococcus mundtiiATCC 43186)有高度同源性,在系统发育树内位于同一分支。选取菌株Se-9进行生理生化特性鉴定,进一步证实该菌株为蒙氏肠球菌。将菌株Se-9进行薄层层析分析,发现该菌株可以产生两种群体感应信号分子C6-HSL和3OC6-HSL。 相似文献
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蛹虫草子实体中海藻糖含量的测定 总被引：1，自引：1，他引：0
为分析食用菌中海藻糖的含量,以蛹虫草子实体为材料,比较了提取溶剂、提取方式及提取时间等条件对海藻糖提取效果的影响,确定海藻糖分析的前处理方法为：1g子实体粉中加入100mL 90%乙醇热回流提取1h。采用高效液相色谱法测定海藻糖,优化后的色谱条件为：SUGAR SP0810柱（300mm×8mm）,超纯水洗脱,流速0.5mL/min,柱温70℃,示差折光检测器检测,进样量10μL。方法学考察结果表明,该方法准确度高,稳定性、精密度、重现性好,对海藻糖标准品的检测特异性良好,适用于蛹虫草子实体中海藻糖含量的 相似文献
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To evaluate bile acid (BA) metabolism in detail, we established a method for analyzing BA composition in various tissues and intestinal contents using ultra performance liquid chromatography/electrospray ionization mass spectrometry (UPLC/ESI-MS). Twenty-two individual BAs were determined simultaneously from extracts. We applied this method to define the differences in BA metabolism between two rat strains, WKAH and DA. The amount of total bile acids (TBAs) in the liver was significantly higher in WKAH than in DA rats. In contrast, TBA concentration in jejunal content, cecal content, colorectal content, and feces was higher in DA rats than in WKAH rats. Nearly all BAs in the liver were in the taurine- or glycine-conjugated form in DA rats, and the proportion of conjugated liver BAs was up to 75% in WKAH rats. Similar trends were observed for the conjugation rates in bile. The most abundant secondary BA in cecal content, colorectal content, and feces was hyodeoxycholic acid in WKAH rats and omega-muricholic acid in DA rats. Analyzing detailed BA profiles, including conjugation status, in a single run is possible using UPLC/ESI-MS. This method will be useful for investigating the roles of BA metabolism under physiological and pathological conditions. 相似文献
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Declan Williams Peihong Zhu Peter Bowden Catherine Stacey Mike McDonell Paul Kowalski Jane Marie Kowalski Ken Evans Eleftherios P. Diamandis K. W. Michael Siu John Marshall 《Clinical proteomics》2006,2(1-2):67-89
There is a great desire to relate the patterns of endogenous peptides in blood to human disease and drug response. The best practices for the preparation of blood fluids for analysis are not clear and also relatively few of the peptides in blood have been identified by tandem mass spectrometry. We compared a number of sample preparation methods to extract endogenous peptides including C18 reversed phase, precipitation, and ultrafiltration. We examined the results of these sample preparation methods by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and liquid chromatography-tandem mass spectrometry (MS/MS) using MALDI-TOF/TOF and electrospray ionization-ion trap. Peptides from solid-phase extraction with C18 in the range of hundreds of femtomoles per spot were detected from the equivalent of 1 μL of serum by MALDI-TOF. We observed endogenous serum peptides from fibrinogen α- and β-chain, complement C3, α-2-HS-glycoprotein, albumin, serine (or cysteine) proteinase inhibitor, factor VIII, plasminogen, immunoglobulin, and other abundant blood proteins. However, we also recorded significant MS/MS spectra from tumor necrosis factor-α-, major histocompatibility complex-, and angiotensin-related peptides, as well as peptides from collagens and other low-abundance proteins. Amino acid substitutions were detected and a phosphorylated peptide was also observed. This is the first time the endogenous peptides of fetal serum have been examined by MS and where peptides from low-abundance proteins, phosphopeptides, and amino acid substitutions were detected. 相似文献
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Kessiri Kongmanas Hongbin Xu Arman Yaghoubian Laura Franchini Luigi Panza Fiamma Ronchetti Kym Faull Nongnuj Tanphaichitr 《Journal of lipid research》2010,51(12):3548-3558
Seminolipid, also known as sulfogalactosylglycerolipid (SGG), plays important roles in male reproduction. Therefore, an accurate and sensitive method for SGG quantification in testes and sperm is needed. Here we compare SGG quantitation by the traditional colorimetric Azure A assay with LC-ESI-MS/MS using multiple reaction monitoring (MRM). Inclusion of deuterated SGG as the internal standard endowed accuracy to the MRM method. The results showed reasonable agreement between the two procedures for purified samples, but for crude lipid extracts, the colorimetric assay significantly overestimated the SGG content. Using ESI-MS/MS MRM, C16:0-alkyl/C16:0-acyl SGG of Cgt+/− mice was quantified to be 406.06 ± 23.63 μg/g testis and 0.13 ± 0.02 μg/million sperm, corresponding to 78% and 87% of the wild-type values, respectively. CGT (ceramide galactosyltransferase) is a critical enzyme in the SGG biosynthesis pathway. Cgt−/− males depleted of SGG are infertile due to spermatogenesis arrest. However, Cgt+/− males sire offspring. The higher than 50% expression level of SGG in Cgt+/− animals, compared with the wild-type expression, might be partly due to compensatory translation of the active CGT enzyme. The results also indicated that 78% of SGG levels in Cgt+/− mice were sufficient for normal spermatogenesis. 相似文献
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目的:建立高效液相色谱-串联质谱(HPLC-ESI-MS/MS)检测基因组DNA甲基化水平的方法。方法:以5-mdC和dG为标准品,采用全自动高效液相色谱系统进行分离,串联电喷雾质谱检测,选择多反应监测模式(MRM)测定标准品,绘制标准工作曲线。结果:在MRM模式下选取5-mdC(m/z 241.9→126.3)和dG(m/z 268.1→152.3)分别作为定量检测的母子离子对,各化合物能实现良好的基线分离;5-mdC和dG碰撞能均为15 eV,去簇电压分别为40和45 V,最低定量限分别为1.65和2.47 fmol;标准品的响应值比为90%~110%;5-mdC含量的天内相对标准偏差和天间相对标准偏差均小于8%。结论:HPLC-ESI-MS/MS是能应用于检测基因组DNA甲基化的一种高通量、高准确率、高分辨率、高灵敏度且重复性好的方法。 相似文献
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The Chinese Pharmacopoeia indicates the use of field thistle (Cirsium setosum) and Japanese field thistle (C. japonicum) in the treatment of bleeding and inflammation. In the absence of an analytical method for the differentiation and analysis of these two species, TLC and HPLC-MS methods have been developed for this purpose. Both species could be readily distinguished by their flavonoid pattern as revealed by TLC on silica gel layers eluted with ethyl acetate:formic acid:acetic acid:water. The quantitative determination of four flavonoids, namely hispidulin-7-neohesperidoside, linarin, pectolinarin and luteolin, was possible using HPLC. Their optimum separation was achieved on a C12 column eluted with water and 0.025% trifluoroacetic acid in acetonitrile. HPLC-MS experiments were performed to confirm peak identity. In samples of C. japonicum, pectolinarin was the major flavonoid (0.32-2.00%), followed by linarin, hispidulin-7-neohesperidoside and luteolin; the total flavonoid content varied from 0.81 to 3.67%. In C. setosum only one flavonoid (linarin; 1.36-2.83%) was assignable. The HPLC method was validated for linearity, limit of detection (< or = 1.7 ng on-column), peak purity, repeatability (< or = 2.3%) and accuracy (recovery rates of spiked samples were between 99.2 and 101.6%). 相似文献
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Mammea coumarins are isoprenylated 4-alkyl or 4-phenylcoumarins. Their distribution is limited to 3 Clusiaceae/Calophyllaceae genera. We recently reported on their presence in Mammea neurophylla bark extracts, where they exhibited anti-AGE properties associated with a prevention of the endothelial dysfunction. About 120 mammea coumarins were already described so, in order to focus further phytochemical analysis on original or bio-active compounds, we developed a methodology to facilitate the detection and identification of compounds of interest. Our aim was to develop a LC-DAD–ESI-MSn method for rapid, sensitive and simple analysis of the mammea coumarins in calophyllaceous/clusiaceous species. For that, full LC-DAD–MSn data were acquired from 11 4-phenylcoumarins previously isolated in our laboratory. Bark, leaves and fruits of M. neurophylla were then extracted with DCM using an ASE apparatus. Extracts were finally analyzed through LC-DAD–HRMSn and UV and MS profiles were compared to our database as well as literature data. Detected new compounds were isolated and their structures elucidated through 1H, 13C and 2D NMR analysis. Finally, 24 known mammea coumarins were dereplicated from bark, leaf and fruit DCM extracts of M. neurophylla and the structure of 4 unreported compounds could be predicted. In particular, the structures of mammea A/AA 9-hydroxyCycloF and mammea A/AB 9-hydroxyCycloF were confirmed after purification and extensive NMR analyses. By comparison of UV and mass fragmentation data from a small library of reference compounds, LC-DAD–HRMSn analysis of mammea coumarins in crude extracts allows the structure prediction of novel or bio-active compounds. This useful guiding-tool could be easily applied to other Clusiaceae/Calophyllaceae phytochemical analysis. 相似文献
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Leachate of oat hulls ( Avena sativa L. cv. Sang) inhibits root elongation and causes swollen roots and abundant root hair formation. The active substance was isolated by column chromatography and thin layer chromatography (TLC) systems. High performance liquid chromatography (HPLC) revealed 3 peaks, one of which corresponded to the substance responsible. The latter was identified as tryptophan by means of its UV spectrum, amino acid analysis, nuclear magnetic resonance spectrometry (NMR) and mass spectrometry (MS). 相似文献
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Mazzella N Molinet J Syakti AD Dodi A Doumenq P Artaud J Bertrand JC 《Journal of lipid research》2004,45(7):1355-1363
This work set out to optimize the detection and separation of several phospholipid molecular species on a reversed-phase column with the use of an electrospray ionization/mass spectrometry-compatible counter-ion. An application of this technique concerned a qualitative and quantitative analysis of bacterial membrane phospholipids extracted from Corynebacterium species strain 8. The phospholipid classes of strain 8 were identified as phosphatidylglycerol, phosphatidylinositol, diphosphatidylglycerol, and a peculiar lipid compound, acyl phosphatidylglycerol. Most of the molecular species structures were elucidated, and regarding phosphatidylglycerol, the fatty acid positions were clearly determined with the calculation of the sn-2/sn-1 intensity ratio of the fatty acyl chain fragments. 相似文献
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Mashego MR Wu L Van Dam JC Ras C Vinke JL Van Winden WA Van Gulik WM Heijnen JJ 《Biotechnology and bioengineering》2004,85(6):620-628
First, we report the application of stable isotope dilution theory in metabolome characterization of aerobic glucose limited chemostat culture of S. cerevisiae CEN.PK 113-7D using liquid chromatography-electrospray ionization MS/MS (LC-ESI-MS/MS). A glucose-limited chemostat culture of S. cerevisiae was grown to steady state at a specific growth rate (mu)=0.05 h(-1) in a medium containing only naturally labeled (99% U-12C, 1% U-13C) carbon source. Upon reaching steady state, defined as 5 volume changes, the culture medium was switched to chemically identical medium except that the carbon source was replaced with 100% uniformly (U) 13C labeled stable carbon isotope, fed for 4 h, with sampling every hour. We observed that within a period of 1 h approximately 80% of the measured glycolytic metabolites were U-13C-labeled. Surprisingly, during the next 3 h no significant increase of the U-13C-labeled metabolites occurred. Second, we demonstrate for the first time the LC-ESI-MS/MS-based quantification of intracellular metabolite concentrations using U-13C-labeled metabolite extracts from chemostat cultivated S. cerevisiae cells, harvested after 4 h of feeding with 100% U-13C-labeled medium, as internal standard. This method is hereby termed \"Mass Isotopomer Ratio Analysis of U-13C Labeled Extracts\" (MIRACLE). With this method each metabolite concentration is quantified relative to the concentration of its U-13C-labeled equivalent, thereby eliminating drawbacks of LC-ESI-MS/MS analysis such as nonlinear response and matrix effects and thus leads to a significant reduction of experimental error and work load (i.e., no spiking and standard additions). By coextracting a known amount of U-13C labeled cells with the unlabeled samples, metabolite losses occurring during the sample extraction procedure are corrected for. 相似文献