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1.
《Acta Botanica Sinica》1988,30(5):534-538
从窿缘桉(Eucalyptus exserta F.Muell.)树叶中分离并鉴定了榈酸,(+)-儿茶素和杨梅酮葡萄糖甙化合物,及以乙酰衍生物形式分离出二种黄烷-3-醇 的二聚体B1和B3,并进行了鉴定,通过水解,花色素,间苯三酚降解反应以及旋光,紫外光谱,高效液相色谱,红外光谱,13C核磁共振等研究,确定缩合类单宁部分是原花青定(少量原翠雀定),其终端单元由(+)-儿茶素构成,延伸单元是(-)-表儿茶素,联结方式是C4-C8联结,黄烷-3-醇的平均聚合度为4-5。  相似文献   

2.
从窿缘桉(Eucalyptus exserta F.Muell.)树叶中分离并鉴定了榈酸,(+)-儿茶素和杨梅酮葡萄糖甙化合物,及以乙酰衍生物形式分离出二种黄烷-3-醇 的二聚体B1和B3,并进行了鉴定,通过水解,花色素,间苯三酚降解反应以及旋光,紫外光谱,高效液相色谱,红外光谱,13C核磁共振等研究,确定缩合类单宁部分是原花青定(少量原翠雀定),其终端单元由(+)-儿茶素构成,延伸单元是(-)-表儿茶素,联结方式是C4-C8联结,黄烷-3-醇的平均聚合度为4-5。  相似文献   

3.
云南“生态茶”的化学成分   总被引:28,自引:7,他引:21  
从云南西双版纳产大叶茶(Camelliasinensisvar.assamica)制成的“生态茶”中分离到11个化合物和1个混晶,经光谱测定,11个化合物分别鉴定为没食子酸、(+)儿茶素、(-)表儿茶素、(-)没食子儿茶素、(-)表没食子儿茶素、(-)表儿茶素-3-0没食子酸酯、(-)表没食子儿茶素-3-O没食子酸酯、茶素、1,4,6-三役食子酰基-β-D葡萄糖1-O-没食子酰基-4,6-(-)-六羟基联苯二甲醚基-β-D-葡萄糖以及咖啡因;混晶为芦丁和山奈酚-3-芸香糖甙的混合物。这是对国产大叶茶的第一次较详细的化学研究。  相似文献   

4.
吡喃酮类衍生物对水稻的杀雄作用与活性氧代谢的关系   总被引:3,自引:0,他引:3  
在幼穗发育的雌雄蕊形成期用化学杀雄剂Ⅲ号(一种吡喃酮类衍生物)30mg/m2处理灿稻HX-3和粳稻镇稻88后,其幼穗,疑花和花药中的活性氧产生速率和丙二醛(MDA)积累高于对照,而过氧化物酶(POD),抗坏血酸过氧化物酶(ASA-POD),过氧化氢酶(CAT),超氧化物歧化酶(SOD)活性则低于对照。在处理后第5天,与对照相比,幼穗中H2O2,O2-,MDA含量明显增高,而相关的抗氧化酶活性下降,至处理后第15天,花药中H2O2,O2,MDA含量均比对照增加约1.5倍以上,同时POD,ASA-POD,SOD活性比对照下降一半以上,化学杀雄剂Ⅲ号处理水稻导致雄性不育的发生,可能与幼穗,颖花和花药中较高的活性氧积累和膜脂过氧化加剧,从而损伤幼穗及花药细胞结构有关。  相似文献   

5.
为了建立金樱根中没食子酸和儿茶素含量的测定方法,分析广西不同产地金樱根及炮制品中没食子酸和儿茶素含量的变化,该文以没食子酸和儿茶素的含量作为指标成分,采用HPLC法对广西产金樱根生品、炒炙品、酒炙品、盐炙品及醋炙品进行测定,并采用SPSS 23.0软件进行方差分析和聚类分析。结果表明:广西不同产地金樱根及炮制品中没食子酸和儿茶素含量均存在差异,所有样品中儿茶素的含量均比没食子酸高,南部地区(除贵港桂平外)的没食子酸和儿茶素含量整体上比北部地区高,在炮制品中醋炙后没食子酸和儿茶素含量最高。该研究表明HPLC测定方法简单可行,金樱根中没食子酸和儿茶素含量的变化差异主要表现为产地地域及炮制方法的不同,可为今后金樱根资源的合理利用、质量标准制定以及临床用药的研究提供一定科学依据。  相似文献   

6.
目的:以对照药材技术要求为基础,以等量同质为原则,利用现代的提取制备技术,制备成质量稳定、均匀性好的苦杏仁对照提取物。通过考察不同的薄层系统,建立薄层鉴别用对照提取物的质量标准,供中药标准中薄层鉴别使用。并对其主要药效成分进行方法学考察,确保今后制备的对照提取物的一致性。方法:采用不同薄层色谱系统对苦杏仁对照提取物可替代对照药材进行定性研究;并用高效液相色谱法测定苦杏仁对照提取物中苦杏仁苷的含量。结果:在苦杏仁对照提取物薄层色谱中,展开剂:为甲苯-甲酸乙酯-甲醇-甲酸-水(6∶2∶0.4∶0.1∶0.1 ),在与对照药材色谱相应位置上,显相同颜色的斑点。HPLC测定苦杏仁对照提取物中苦杏仁苷含量,苦杏仁苷线性范围461.7~15.39 mg/L(r=0.9995),平均回收率为101 .1%(RSD=2.15%),该方法准确、可靠、专属性强,重复性好。结论:苦杏仁对照提取可替代对照药材进行定性鉴别。  相似文献   

7.
用MspⅠ/HpaⅡ酶解电泳法和高效液相色谱(HPLC)两种方法进行比较,研究了不同年龄大鼠的肝、脑细胞基因组DNA的甲基化程度。从酶解电泳图谱可观察到,肝、脑细胞基因组DNA甲基化在青年鼠和老年鼠之间没有差异。但用具有高分辨率的高效液相色谱测量DNA中5-mC的含量时发现,老年鼠脑细胞DNA甲基化程度较大年鼠的下降62%,而肝细胞DNA甲基化程度在老年鼠与青年鼠之间并没有显著差异。这些结果提示:(1)用常规的酶解电泳法所分析的DNA甲基化结果并不能反映整个基因组DNA甲基化的水平。(2)衰老过程中,不同组织DNA甲基化的改变存在差异,引起这种差异的原因可能与组织的增殖和分化程度有关。进一步分析脑细胞原癌基因c-Ha-ras的甲基化水平,无论MspⅠ酶切图谱,还是HpaⅡ酶切图谱均可观察到分子大小为19kb、7.5kb、1.3kb、0.9kb的四条阳性带,说明该基因未发生甲基化,且与年龄无关。  相似文献   

8.
目的:建立锁阳的HPLC指纹图谱,结合化学计量学和网络药理学技术探讨锁阳的最佳质量标志物(Q-marker),为锁阳的质量控制与评价提供参考.方法:采用高效液相色谱法(HPLC)建立锁阳的指纹图谱,建立正交偏最小二乘(OPLS)模型探讨HPLC指纹图谱上的质量差异性成分;从TCMSP、TTD、BATMAN-TCM等数据...  相似文献   

9.
建立滁菊的HPLC指纹图谱,结合化学计量学手段对不同滁菊的指纹图谱进行分析研究,以期为滁菊的质量控制和产地追溯提供依据。采用HPLC法建立指纹图谱,并用中药色谱指纹图谱相似度评价系统(2012版)和系统聚类、主成分分析2种化学计量学法对指纹图谱和特征峰进行分析。分析结果发现样品有27个共有峰,12个滁菊样品具有较高的相似度,杭菊与滁菊的相似度较差,聚类分析与主成分分析结果和相似度分析结果一致。将HPLC指纹图谱与化学计量学结合可对滁菊进行鉴别和质量评价,为其质量控制和追溯提供了理论参考。  相似文献   

10.
裂褶菌纤维二糖脱氢酶(CDH)可以氧化纤维二糖并还原多种物质,催化的是一双底物双产物反应,符合乒乓反应机制,在电子供体纤维二糖存在下,CDH可以还原由豆壳过氧化物酶(SHP)氧化多种芳香化合物所生成的产物,SHP氧化1-羟基苯丙三唑(1-hydroxybezotriazole,HBT)生成的产物对SHP有失活作用,而在纤维二糖存在下,CDH可以还原该氧化产物从而阻止其对酶的失活作用,CDH可以抑制  相似文献   

11.
Black tea is a highly popular beverage, and its pigments, polymerized catechins such as theaflavins (TFs), are attracting attention due to their beneficial health effects. In this study, to test the inhibitory activities of TFs on the intestinal absorption of cholesterol, we investigated their effects on phosphatidylcholine (PC) vesicles in the absence or presence of a bile salt. (?)-Epicatechin gallate, (?)-epigallocatechin gallate, and TFs formed insoluble complexes with PC vesicles. Galloylated TFs such as TF2A, TF2B, and TF3 precipitated far more than other polyphenols. The subsequent addition of taurocholate redispersed the polyphenol-PC complexes, except that a large amount of TF2A remained insoluble. After incubation with taurocholate-PC micelles, TF2A elevated the turbidity of the micelle solution, providing red sediments. The TF2A-specific effect was dependent on the PC concentration. These results suggest that TF2A interacts with PC and aggregates in a specific manner different from catechins and other TFs.  相似文献   

12.
A New Form of Myelin Basic Protein Found in Human Brain   总被引:2,自引:0,他引:2  
Human myelin basic protein was subjected to ion-exchange chromatography at high pH to separate the differently charged components. Polyacrylamide gel electrophoretic patterns of the fractions showed that the less basic fractions 3, 4, and 5 contained significant amounts of a protein somewhat smaller than the more common 18.5-kDa form. Fraction 3 consisted of approximately equal amounts of this smaller polypeptide and component 3, the 18.5-kDa form found in other mammalian myelin basic protein preparations. The two proteins in fraction 3 were separated by fast protein liquid chromatography. Both have blocked N termini and identical C termini (-Met-Ala-Arg-Arg). When the tryptic digests of the two proteins were fractionated by HPLC, the elution profiles were similar, except that four peaks found in the chromatogram of the larger protein were missing from the chromatogram of the smaller one. In addition, an extra peak was found in the elution pattern of the latter chromatogram. Amino acid analysis of the individual tryptic peptides indicated that the smaller protein lacked residues 106-116 (-Gly-Arg-Gly-Leu-Ser-Leu-Ser-Arg-Phe-Ser-Trp-). The deleted portion corresponds exactly to the amino acid sequence encoded by exon 5 of the mouse basic protein gene. This new form of myelin basic protein has a molecular weight of 17,200, calculated from its amino acid composition.  相似文献   

13.
应用HPLC方法测定了薯蓣属根状茎组10种1亚种1变种植物23个样本,建立了萆薢类药材总皂苷元粗提物的HPLC指纹图谱.色谱柱为Zorbax Eclipse XDB-C_(18)柱(4.6×250 mm,5 μm),流动相为乙腈-水,柱温30℃,检测波长为203 nm.结果表明,用上述条件所建立的指纹图谱共标示出7个共有峰,且可较全面地反映萆薢类药材的皂苷元类成分,为萆薢类药材薯蓣属根状茎组植物鉴别及质量控制提供一种方法.  相似文献   

14.
A range of catechins and oligomeric procyanidins was purified by high performance liquid chromatography (HPLC) from grape seed, apple skin, lentil and almond flesh. Catechins, galloylated epicatechin, glycosylated catechin, procyanidin dimers, galloylated dimers, trimer, and tetramer species were all identified, purified and quantified by HPLC, LC-MS and NMR. The antioxidant properties of these compounds were assessed using two methods: (a) inhibition of ascorbate/iron-induced peroxidation of phosphatidylcholine liposomes; (b) scavenging of the radical cation of 2,2′-azinobis(3-ethyl-benzothiazoline-6-sulphonate) (ABTS) relative to the water-soluble vitamin E analogue Trolox C (expressed as Trolox C equivalent antioxidant capacity, TEAC). Antioxidant activity in the lipid phase decreased with polymerisation in contrast with antioxidant action in the aqueous phase which increased from monomer to trimer and then decreased from trimer to tetramer. Galloylation of catechin and dimeric procyanidins decreased lipid phase and increased aqueous phase antioxidant activity. Glycosylation of catechin demonstrated decreased activity in both phases.  相似文献   

15.
A range of catechins and oligomeric procyanidins was purified by high performance liquid chromatography (HPLC) from grape seed, apple skin, lentil and almond flesh. Catechins, galloylated epicatechin, glycosylated catechin, procyanidin dimers, galloylated dimers, trimer, and tetramer species were all identified, purified and quantified by HPLC, LC-MS and NMR. The antioxidant properties of these compounds were assessed using two methods: (a) inhibition of ascorbate/iron-induced peroxidation of phosphatidylcholine liposomes; (b) scavenging of the radical cation of 2,2'-azinobis(3-ethyl-benzothiazoline-6-sulphonate) (ABTS) relative to the water-soluble vitamin E analogue Trolox C (expressed as Trolox C equivalent antioxidant capacity, TEAC). Antioxidant activity in the lipid phase decreased with polymerisation in contrast with antioxidant action in the aqueous phase which increased from monomer to trimer and then decreased from trimer to tetramer. Galloylation of catechin and dimeric procyanidins decreased lipid phase and increased aqueous phase antioxidant activity. Glycosylation of catechin demonstrated decreased activity in both phases.  相似文献   

16.
Trilinoleoylglycerol (TL) was autoxidized at 37°C in the dark. Monohydroperoxides (MHP) obtained from the oxidized products were analyzed by high performance liquid chromatography (HPLC). Several peaks which appeared in the chromatogram were identified by infrared (IR), gas chromatography mass spectrometry (GC-MS) and enzymatic hydrolysis. Some positional and geometrical isomers of their hydroperoxy fatty acid components were separated using both absorption and reversed phase systems. Furthermore, 1-hydroperoxylinoleoyl-2,3-dilinoleoyl-glycerol and 1,3-dilinoleoyl-2-hydroperoxylinoleoylglycerol were partly separated by HPLC using an absorption system. MHP obtained from autoxidized corn oil, safflower oil and soybean oil were separated into some peaks by HPLC, although resolution into the individual isomers was incomplete. When oxidized oils were subjected to HPLC analysis directly, a linear relationship was observed between the peak areas of MHP and peroxide value in the range of 10 ~ 50 meq/kg.  相似文献   

17.
High-speed countercurrent chromatography (HSCCC) has been applied for the separation of theaflavins and catechins. The HSCCC run was carried out with a two-phase solvent system composed of hexane-ethyl acetate-methanol-water-acetic acid (1:5:1:5:0.25, v/v) by eluting the lower aqueous phase at 2 ml/min at 700 rpm. The results indicated that pure theaflavin, theaflavins-3-gallate, theaflavins-3'-gallate and theaflavin-3,3'-digallate could be obtained from crude theaflavins sample and black tea. The structures of the isolated compounds were positively confirmed by (1)H NMR and (13)C NMR, MS analysis, HPLC data and TLC data. Meanwhile, catechins including epigallocatechin gallate, gallocatechin gallate, epicatechin gallate and epigallocatechin were isolated from the aqueous extract of green tea by using the same solvent system. This study developed a modified method combined with enrichment theaflavins method by using HSCCC for separation of four individual theaflavins, especially for better separation of theaflavins monogallates.  相似文献   

18.
Problems inherent in corticosterone radioimmunoassay (RIA) led to consideration of alternative methods. A high-performance liquid chromatography (HPLC) procedure was evaluated that separated and quantitated dichloromethane-extracted corticosterone by reverse-phase chromatography. The results were correlated (r = 0.92) with an RIA procedure. The HPLC recovered nearly 100% of corticosterone added to rat plasma and had excellent reproducibility. In addition, chromatogram profiles of dichloromethane-soluble components obtained from rat plasma, derived from drug effect studies, could have value for characterizing response patterns. Without automated sample injection equipment, HPLC is more appropriately applied in monitoring RIA results than in processing large numbers of samples.  相似文献   

19.
A new tool, HPLC Studio, was developed for the comparison of high-performance liquid chromatography (HPLC) chromatograms from microbial extracts. The new utility makes it possible to create a virtual chromatogram by mixing up to 20 individual chromatograms. The virtual chromatogram is the first step in establishing a ranking of the microbial fermentation conditions based on either the area or diversity of HPLC peaks. The utility was used to maximize the diversity of secondary metabolites tested from a microorganism and therefore increase the chances of finding new lead compounds in a drug discovery program.  相似文献   

20.
Synthesized oligo probes were immobilized to a HPLC gel in high concentrations (30-40 O.D. per gram dry gel), packed in a column (2mm x 10cm) and incorporated into a conventional HPLC system. The system was applied to the discrimination among homologous sequences. Two probes different in sequence and length (16mer and 24mer) were investigated under isothermal and isocratic conditions. For each probe, 4 oligos of similar sequences, one perfectly matched to the probe and others containing one mismatch in the center of the chain, were synthesized. The chromatogram obtained as the results of high performance liquid affinity chromatography (HPLAC) considerably varied with the column temperature and the type of mismatches. The dependency of the deformation of elution profile upon mismatch seemed to reflect the stability of the hybrid composed of samples and immobilized probe.  相似文献   

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