共查询到20条相似文献,搜索用时 62 毫秒
1.
2.
3.
综合使用硅胶柱色谱、HP20大孔树脂柱色谱、ODS反相柱色谱及Sephadex LH-20凝胶柱色谱等色谱技术对木荷(Schima superba)茎皮进行分离纯化,并根据化合物理化性质以及应用MS、NMR技术对分离得到的化合物进行结构鉴定。从木荷中分离得到9个化合物,分别鉴定为三十烷酸(1)、棕榈酸(2)、Dodecanoic acid(3)、松脂素(4)、槲皮素(5)、山柰酚(6)、Americanin A(7)、槲皮素-3-O-β-D-葡萄糖苷(8)及槲皮素-3-O-α-L-鼠李糖苷(9)。化合物1~4 为首次从木荷中分离得到,化合物5、7、9 为首次从木荷属植物中分离得到。 相似文献
4.
对来源于冬虫夏草中分离得到的内生菌Penicillium crustosum的次级代谢产物和抑菌活性进行研究.采用硅胶柱色谱、MCI柱色谱和半制备HPLC等色谱技术对其进行分离纯化,通过NMR结合质谱进行化学成分鉴定.分离并鉴定16个化合物,分别为:Ac-L-Leu-L-Pro-OCH3(1)、(E)-3-benzyl... 相似文献
5.
研究菊状千里光的化学成分,为进一步探讨其药理作用提供理论依据.菊状千里光乙醇提取物经大孔树脂初步分离后,采用凝胶色谱、硅胶色谱、MCI等方法分离纯化化合物,通过化合物的理化性质与波谱数据分析鉴定其结构.使用MTT法测定分离得到的两个生物碱对正常肝细胞L-02的毒性,并通过琼脂平板打孔法对菊状千里光中得到的部分化合物进行... 相似文献
6.
本文对糙叶五加果实正丁醇萃取物的抗炎活性成分进行研究.采用硅胶柱色谱、C18柱色谱、LH-20型羟丙基葡聚糖凝胶(Sephadex LH-20)柱色谱、半制备液相及重结晶等方法进行分离纯化,利用波谱分析结合理化性质鉴定化合物的结构.从糙叶五加果实正丁醇萃取部位中分离鉴定出17个化合物,分别为槲皮素-3-O-β-D-吡喃... 相似文献
7.
通过对菌株r DNA-ITS序列和系统发育多样性进行分析,鉴定该菌株为赛氏曲霉;对赛氏曲霉用大米培养基进行固体发酵培养,对其发酵产物采用有机溶剂萃取、硅胶柱色谱层析、反相ODS柱色谱层析、薄层色谱层析、Sephadex LH-20凝胶柱色谱层析和制备型高效液相色谱等分离纯化手段进行分离,得到7个单体化合物。对分离得到单体化合物采用质谱、核磁共振氢谱、核磁共振碳谱、二维核磁共振等现代波谱技术对其进行结构鉴定;对单体化合物的MIC值进行测定,其中化合物L-1对耐甲氧西林金黄色葡萄球(MRSA)、耐甲氧西林表皮葡萄球菌(MRSE)有一定的抑菌活性,对大肠杆菌有明显的抑菌活性。 相似文献
8.
本文报道了对山楝Aphanamixis polystachya枝叶的化学成分进行研究.采用硅胶柱色谱、Sephadex LH-20、RP-C18、HPLC等色谱分离手段,从其95%乙醇提取物中分离得到9个化合物,通过波谱方法进行鉴定为polystachyadione A(1)、polystachyadione B (2... 相似文献
9.
新疆蓝刺头化学成分研究 总被引:1,自引:0,他引:1
以新疆蓝刺头(Echinops ritro L.)全草为研究材料,通过硅胶柱色谱,Sephadex LH-20柱色谱,重结晶等技术对新疆蓝刺头化学成分进行分离纯化,通过理化性质分析及1H-NMR,13C-NMR等技术对化合物结构进行鉴定.结果表明,共分离出5个化合物,分别是三萜类化合物蒲公英甾醇乙酰酯(化合物1)、蒲公英甾醇(化合物2)、黄酮苷类化合物金丝桃苷(化合物3)、胡萝卜苷(化合物4)与β-豆甾醇葡萄糖苷(化合物5).其中化合物1,2,5首次从该种植物中分离,化合物3为首次从该属植物中分离. 相似文献
10.
为研究大叶土蜜树(Bridelia retusa)茎的化学成分及其抗神经炎活性,采用色谱技术从大叶土蜜树茎部分95%乙醇提取物中分离得到11个化合物。通过核磁共振波谱、质谱以及与文献数据比较,化合物结构鉴定为没食子酸(1)、木栓酮(2)、阿魏酸二十七烷脂(3)、芥子醛(4)、丁香醛(5)、丁香脂素(6)、补骨脂素(7)、补骨脂酚(8)、二十五烷酸(9)、亚油酸(10)和1-Linoleoylglycerol(11)。其中化合物3~11为首次从土蜜树属中分离得到。对化合物1~11的抗神经炎活性进行评价,发现化合物4、5、10和11对LPS诱导BV-2细胞NO生成具有显著抑制作用,其IC50分别为12. 57、8. 41、5. 86、5. 86μM。 相似文献
11.
The phylogenetic relationships of the late Eocene anthropoids Catopithecus browni and Proteopithecus sylviae are currently a matter of debate, with opinion divided as to whether these taxa are stem or crown anthropoids. The phylogenetic position of Catopithecus is of particular interest, for, unlike the highly generalized genus Proteopithecus, this taxon shares apomorphic dental and postcranial features with more derived undoubted catarrhines that appear in the same region 1-2 Ma later. If these apomorphies are homologous and Catopithecus is a stem catarrhine, the unique combination of plesiomorphic and apomorphic features preserved in this anthropoid would have important implications for our understanding of the crown anthropoid morphotype and the pattern of morphological character transformations that occurred during the early phases of stem catarrhine evolution.Well-preserved astragali referrable to Proteopithecus, Catopithecus, and the undoubted early Oligocene stem catarrhine Aegyptopithecus have provided additional morphological evidence that allows us to further evaluate competing hypotheses of interrelationships among Eocene-Oligocene Afro-Arabian anthropoids. Qualitative observations and multivariate morphometric analyses reveal that the astragalar morphology of Proteopithecus is very similar to that of early Oligocene parapithecids and living and extinct small-bodied platyrrhines, and strengthens the hypothesis that the morphological pattern shared by these taxa is primitive within crown Anthropoidea. In contrast, Catopithecus departs markedly from the predicted crown anthropoid astragalar morphotype and shares a number of apomorphic features (e.g., deep cotylar fossa, laterally projecting fibular facet, trochlear asymmetry, mediolaterally wide astragalar head) with Aegyptopithecus and Miocene-Recent catarrhines. The evidence from the astragalus complements other independent data from the dentition, humerus and femur of Catopithecus that support this taxon's stem catarrhine status, and we continue to maintain that oligopithecines are stem catarrhines that constitute the sister group of a clade containing propliopithecines and Miocene-Recent catarrhines. 相似文献
12.
该文采用光学显微镜,首次对九种瘤足蕨属植物的叶柄和羽片横切面进行了解剖学比较研究。结果表明:九种瘤足蕨属植物在叶柄中部横切面的表皮、基本组织和中柱以及营养叶羽片的表皮、叶肉和主脉等结构特征是相似的,如叶柄中部横切面的表皮不被毛或是鳞片,表皮细胞形状呈类圆形,具有厚壁组织,中柱为周韧型维管束;营养叶羽片横切面的气孔只分布于下表皮,表皮细胞形状呈扁平状,主脉的结构类型属于周韧型维管束。在系统的演化中,瘤足蕨与桫椤科植物有一定的亲缘关系,两者既有相似的特征但也表现出一定的差异,支持瘤足蕨属是一个自然分类的观点。九种瘤足蕨属植物叶柄中部横切面形状有梯形、椭圆形和三角形,叶柄中部横切面维管束的形状成"U"字形、"V"字形或"品"字形;维管束数目1个或3个;维管束结构中的木质部成"八"字形、"U"字形或"一"字形;羽片主脉下侧形成了以三角形、弧形或梯形的突起;叶柄中的木质部形态有两种,即典型的海马形状以及非典型的海马形状,其中典型的海马形状的特点为叶柄的木质部两侧都呈现弯曲成钩的形态,非典型的海马形状特点为2个木质部束的两侧都未出现弯曲成钩的形态或者是其中的一个木质部一端无弯曲成钩的形态,这些形态解剖特征稳定且具类群特异性,为瘤足蕨属植物的分类和系统学研究提供了新的依据。同时,依据其叶柄和羽片横切面解剖叶柄学特征列出了瘤足蕨属植物分种检索表。 相似文献
13.
14.
Ragnhild Aakre Jakobsen Miguel A. Gutierrez Heidrun I. Wergeland 《Fish & shellfish immunology》1999,9(8):413
Atlantic salmon (Salmo salar L.) immunised with A-layer positive or A-layer negative strains ofAeromonas salmonicida did not produce antibodies reactive with proteinase K-digested LPS in the low molecular weight area corresponding to the core-region of LPS. The salmon produced antibody titres as high as those produced by rabbit when assayed against whole bacteria or LPS in ELISA. The salmon antibodies against the A-layer positive strain of A. salmonicida lysed rabbit erythrocytes sensitised with LPS from the A-layer positive strain of A. salmonicida. This was in contrast to the non-haemolytic activity of the salmon antibodies against the A-layer negative strain, indicating differences in epitopes between the two strains. 相似文献
15.
A revised stratigraphy for the early hominid site of Sterkfontein (Gauteng Province, South Africa) reveals a complex distribution of infills in the main excavation area between 2.8 and 1.4 m.y.a, as well as deposits dating to the mid to late Pleistocene. New research now shows that the Member 4 australopithecine breccia (2.8-2.6 Ma) extends further west than was previously thought, while a late phase of Member 4 is recognized in a southern area. The artefact-bearing breccias were defined sedimentologically as Member 5, but one supposed part of these younger breccias, the StW 53 infill, lacks in situ stone tools, although it does appear to post-date 2.6 Ma when artefacts first appear in the archaeological record. The StW 53 hominid, previously referred to Homo habilis, is here argued to be Australopithecus. The first artefact-bearing breccia of Member 5 is the Oldowan Infill, estimated at 2-1.7 Ma. It occupies a restricted distribution in Member 5 east and contains an expedient, flake-based tool industry associated with a few fossils of Paranthropos robustus. An enlarged cave opening subsequently admitted one or more Early Acheulean infills associated in Member 5 west with Homo ergaster. The artefacts attest to a larger site accumulation between ca. 1.7 and 1.4 Ma, with more intensive use of quartzite over quartz and a subtle but important shift to large flakes and heavier-duty tools. The available information on palaeoenvironments is summarized, showing an overall change from tropical to sub-tropical gallery forest, forest fringe and woodland conditions in Member 4 to more open woodland and grassland habitats in the later units, but with suggestions of a wet localized topography in the Paranthropus -bearing Oldowan Infill. 相似文献
16.
该研究采用TLC方法,对不同产地大罗伞树进行定性鉴别,并采用HPLC方法对大罗伞树不同产地和不同部位的岩白菜素进行了含量测定。其中,色谱柱为Sino Chrom ODS-BP C18(250 mm×4.6,5μm),流动相为甲醇-水(23∶77),流速为1.0 m L·min~(-1),检测波长为275 nm。结果表明:10批不同产地大罗伞树药材的TLC均可检出岩白菜素斑点;10批不同产地大罗伞树药材中岩白菜素平均含量为1.67%,但产地间含量差异较大,最高含量可达2.58%,最低含量0.95%;大罗伞树不同部位中岩白菜素含量有所差异,地下部分(根及根茎)含量较高,平均值为4.05%,地上部分(茎枝和叶)含量较低,平均值为1.21%。所建立的大罗伞树药材TLC鉴别和岩白菜素含量测定方法操作简便、专属性强、重现性好、结果准确。该研究结果能准确鉴别大罗伞树药材真伪,并测定药材中岩白菜素的含量,为大罗伞树药材质量标准的建立提供了依据,对于控制壮药大罗伞树药材质量具有重要意义。 相似文献
17.
不同钙离子浓度对喜钙和嫌钙型金花茶光合及生理指标的影响 总被引:1,自引:0,他引:1
为探讨喜钙型金花茶对高钙环境的生理适应机制以及嫌钙型金花茶的避钙机理,该文采用砂培法,分别以两种喜钙型金花茶[直脉金花茶(Camellia multipetala)、柠檬金花茶(C.limonia)]和两种嫌钙型金花茶[金花茶(C.nitidissima)、东兴金花茶(C.tunghinensis)]的幼苗为材料,用不同浓度(设为5、25、50、100 mmol·L-1)的钙离子(Ca2+)营养液进行培养,研究其对两种不同类型金花茶的光合及生理指标的影响。结果表明:两种嫌钙型金花茶的净光合速率(P n)、气孔导度(G s)、实际光化学效率(ΦPSⅡ)、电子传递效率(ETR)、叶绿素a(Chl a)、叶绿素b(Chl b)、叶绿素总量[(Chl(a+b)]均随Ca2+浓度的升高而降低,表明高钙环境降低了嫌钙型金花茶的光合能力;喜钙型金花茶的这些指标在不同Ca2+浓度下无显著变化,高钙环境未影响其光合作用的正常进行。嫌钙型金花茶叶片丙二醛含量和PSⅡ最大光化学效率(F v/F m)在高钙环境下未有显著变化,表明其光合膜系统还未受到伤害。随着Ca2+浓度的升高,嫌钙型金花茶叶片脯氨酸含量显著增加,而可溶性糖含量变化却不大;喜钙型金花茶在不同Ca2+浓度下脯氨酸和可溶性糖含量的变化均不明显,但其可溶性糖含量却明显高于嫌钙型金花茶。喜钙型金花茶对外界钙离子浓度的变化不敏感,其适应高钙的生理机制可能与叶片较高的可溶性糖含量有关;而嫌钙型金花茶对高钙环境的适应性较差,这可能是其不能在钙质土上生长的主要原因。 相似文献
18.
该文描述了自四川西部发现的毛茛科二新种,包括四川乌头属一新种,即泸定乌头(Aconitum ludingense W.T.Wang),此新种隶属于乌头属乌头亚属,以及四川唐松草属一新种,即狭药唐松草(Thalictrum stenantherum W.T.Wang),给出了此新种与其近缘种六脉萼唐松草之间的形态区别. 相似文献
19.
R. J. Whittington B. L. Munday M. Akhlaghi G. L. Reddacliff J. Carson 《Fish & shellfish immunology》1994,4(7)
ELISA methods were used to evaluate the humoral immune responses of rainbow trout (Oncorhynchus mykiss) to ovalbumin and Vibrio anguillarum. Antibody responses to ovalbumin administered intraperitoneally (i.p.) were inconsistent even when Freund's complete adjuvant (FCA) was used and the induction phase (4-6 weeks) of the response was longer compared with the response to V. anguillarum (<4 weeks). Significant elevation in antibody level was noted 3 weeks after bath vaccination with V. anguillarum but levels decreased thereafter. Humoral responses of greatest magnitude occurred where V. anguillarum was given in an emulsion with Freund's complete adjuvant (FCA). However, i.p. administration of FCA alone 3 weeks prior to i.p. immunisation with non-adjuvanted V. anguillarum resulted at 5 weeks in similar elevations in antibody to those in fish given V. anguillarum and FCA concurrently, suggesting that the effects of FCA were not limited to creation of an antigen depot. Proliferation of peritoneal inflammatory cell populations which included macrophages and plasma cells was detected histologically within 3 weeks of administration of FCA, but changes were not detected in the spleen or haematopoietic kidney. 相似文献
20.
为探究独脚金内酯和生长素对黄芪根系生长发育的影响,该研究以膜荚黄芪和蒙古黄芪幼苗为材料,在种子萌发袋中添加不同浓度GR24和IAA(2μmol·L^(-1) GR24、5μmol·L^(-1) IAA和2μmol·L^(-1) GR24+5μmol·L^(-1) IAA),7 d后检测黄芪幼苗主根长和侧根数,并测定内源激素含量、生长素和独脚金内酯相关基因表达量的变化。结果表明:(1)GR24处理显著促进黄芪主根生长。(2)IAA处理下主根生长受到抑制,侧根数明显增加。(3)GR24+IAA处理下主根的生长同样受到抑制,膜荚黄芪侧根数较IAA处理下减少,说明GR24有抑制IAA对侧根发育的诱导作用,但不能缓解IAA对黄芪主根生长的抑制。(4)3种处理下黄芪幼苗根系内源激素含量、生长素和独脚金内酯相关基因表达量发生了显著变化,说明GR24和IAA对黄芪幼苗主根长和侧根数的影响可能与生长素和独脚金内酯相关基因表达及内源激素水平的变化有关。该研究结果初步阐明了黄芪幼苗根系生长发育与GR24和IAA之间的关系,为黄芪规范化育苗和幼苗质量控制提供理论依据,对进一步探索独脚金内酯和生长素调控黄芪根系生长发育的分子机制具有一定的意义。 相似文献