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1.
运用柱层析等分离纯化方法,从蕨菜乙醇提取物的乙酸乙酯萃取部位中分离得到4个黄酮类化合物:3,4,6,2’,4’-五羟基高黄烷醇(1)、槲皮素3-O-β-D-葡萄糖苷(2)、芦丁(3)、槲皮素3-O-β-D-葡萄糖苷(4),其中化合物1为新化合物,也是从蕨类植物中分离出的第一个高黄烷酮,化合物2为首次从该植物中分离得到。采用MTT法对获得的黄酮类化合物的细胞毒活性测定结果表明化合物1具有明显的细胞毒活性。  相似文献   

2.
本实验研究了茶蜂花粉的抗氧化活性和功效成分。茶蜂花粉85%乙醇回流提取,经过石油醚、乙酸乙酯、正丁醇依次萃取,得到石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物以及萃余物4个部分,用D-半乳糖诱导衰老小鼠模型检测茶蜂花粉不同组分的抗氧化活性,采用多种色谱方法分离具有抗氧化活性的成分,利用核磁共振方法鉴定各单体的化学结构。结果表明:茶蜂花粉乙醇提取物、乙酸乙酯萃取物具有明显的抗氧化作用,乙酸乙酯萃取物经MCI柱层析,得到30%、50%、70%三个乙醇洗脱组分,其中30%乙醇洗脱组分具有显著抗氧化活性,从该洗脱部分得到三个单体化合物,经鉴定为:槲皮素、山奈素-3-O-芸香糖苷、山奈酚-3-O-(2″,3″,4″-O-三对羟基桂皮酰基)-β-D-吡喃葡萄糖苷,推测茶蜂花粉具有抗氧化活性的成分主要为黄酮类化合物。  相似文献   

3.
探讨了干柱层析法分离益智渣及益智乙醇提取物的抗氧化成分。实验中采用乙酸乙酯/环己烷(3∶7)、氯仿/甲醇(9∶1)为展开剂依次二次干柱层析分离出抗氧化物质。结果表明,益智渣及益智乙醇提取物均有较强的抗氧化性,益智渣的H2O2清除能力强于益智乙醇提取物。  相似文献   

4.
将瓜果腐霉进行液体发酵,其菌丝用等体积乙酸乙酯和甲醇进行依次萃取,甲醇萃取液旋转蒸发去溶剂后进行硅胶柱层析,以乙酸乙酯和石油醚(V/V=3:1和V/V=2:1)的混合液进行梯度洗脱,每50 mL收集为一个馏分,共收集到40个馏分。生物测定结果表明,以乙酸乙酯和石油醚(V/V=2:1)洗脱得到的馏分21 24对供试杂草马唐表现出了较强的活性,其对马唐的生长抑制作用均为4级。合并馏分21 24,以乙酸乙酯和石油醚(V/V=2:1)的混合液为展开剂进行等度洗脱,每50 mL收集为一个馏分,共收集到20个馏分。生物测定结果表明,馏分3对马唐有较强的抑制活性。HPLC分析发现,该馏分主要含有3个组分,其保留时间分别为12.7、14.0和30.5 min。  相似文献   

5.
杠柳枝皮的化学成分研究(英文)   总被引:1,自引:0,他引:1  
将杠柳枝皮粉末的乙醇提取物悬浮于水后,依次用石油醚、乙酸乙酯和正丁醇萃取.对乙酸乙酯萃取物采用各种柱层析进行多次分离后得到4个化合物,经波谱分析,鉴定它们的结构分别为β-香树素乙酸酯(1)、β-香树素(2)、periplogenin(3)和perilocoside N(4),其中化合物1和2是首次从该植物中分离得到.  相似文献   

6.
扶芳藤种油中的拒食活性化合物的X—射线晶体结构分析   总被引:5,自引:0,他引:5  
干燥的带假种皮的扶芳藤种子粉碎后,用石油醚提取,回收石油醚得到种油,将种油用80%乙醇萃取,回收乙醇母液,得到的提出物,上硅胶柱层析,再用石油醚:乙酸乙酯梯度洗脱,收集洗脱液,得到一针状结晶,通过测定其物理常数、红外、质谱及X—射线晶体结构分析,确定其为1α、2α、6β、9α、15—五乙酰基—8α—苯甲酰基—六元二氢沉香呋喃酯。生物活性试验(面积法)结果表明:在1000ppm浓度时,它对害虫黄守瓜的拒食率为58.4%。  相似文献   

7.
本试验以对禾本科杂草具有除草活性的瓜果腐霉菌株PAM1为试验材料,研究了X-5、AB-8,H-103和S-8等4种大孔吸附树脂对其除草活性物质的吸附性能,结果表明X-5树脂能够较好地吸附该除草活性物质.选用50%乙醇、95%乙醇、乙酸乙酯和丙酮4种溶剂为供试洗脱溶剂,采用2种洗脱方案,对其最佳洗脱溶剂进行了选择,生长抑制作用和种子萌发试验结果表明,以方案1洗脱为最佳.  相似文献   

8.
本文通过选用特定的吸附柱层析活性炭纯化油茶皂苷。以总皂苷的得率及纯度为考察指标,确定活性炭吸附柱层析富集油茶总皂苷的性能、洗脱参数及再生使用情况。结果表明,水洗之后再以90%乙醇洗脱较好;香草醛.浓硫酸为检测方法检测下,总皂苷解吸得率为62.9%,总洗脱率为92.4%,纯度为50.1%以上;该类柱层析活性炭在分离纯化及脱色方面作用较显著,工艺简便、成本低,适合工业化生产。  相似文献   

9.
目的:建立阿扎霉素B的分离与纯化工艺。方法:将阿扎霉素B的发酵液进行加热处理后,采用乙醇-乙酸乙酯的浸提系统,进行结晶、重结晶和柱层析制备。结果:发酵液经600℃热处理30min后,于室温条件下放置1d,阿扎霉素B的损失率仅为3.9%,阿扎霉素B经柱层析后,纯度达到98.1%,得率达到91.2%。结论:阿扎霉素B发酵液加热处理有利于过滤和离心,可延长发酵液在室温条件下的放置时间,提高阿扎霉素B的稳定性,乙醇-乙酸乙酯的浸提系统有利于提高阿扎霉素B的得率。  相似文献   

10.
本文报道了一种从土木香药材中提取以及纯化倍半萜内酯的方法。乙醇回流提取的方法采用正交试验设计方法[L9(34)],考察了4个因素对产率与内酯浓度的影响,最终确定了乙醇回流提取的最佳方法:药材加10倍量的95%乙醇,加热回流提取1次,2 h。而硅胶柱层析的最佳纯化方法为:以100~200目的硅胶,1∶3的上样量,径高比为1∶2。其洗脱剂成分为石油醚∶丙酮(100∶3,v/v),洗脱流速为35 m L/min。采用该方法,异土木香内酯与土木香内酯的提取率大于70%,其纯度大于90%。  相似文献   

11.
以80%乙醇浸提经乙醚脱脂预处理的干蕨菜粉,减压回收乙醇得浓缩液.浓缩液以8%硫酸沸水浴水解3 h后,加入20%NaOH中和至弱酸性,过滤,滤渣以三氯甲烷索氏提取获总蕨菜黄酮苷元.TLC法检测总黄酮苷元的组成,HPLC法测定其主要苷元的含量.结果表明,通过酸水解获得总蕨菜黄酮苷元,其主要成分为山奈酚,含量约占蕨菜干重的1.9%.  相似文献   

12.
Bioinsecticidal effects of methanol extracts from seven plant species on Tribolium castaneum were investigated. Centaurium erythraea, Peganum harmala, Ajuga iva, Aristolochia baetica, Pteridium aquilinum and Raphanus raphanistrum extracts inhibit growth of larvae. C. erythraea was the most toxic with 63% mortality 10 days after treatment, followed by P. harmala with 58%. C. erythraea and P. aquilinum reduce the emergence rate respectively of 66% and 19%. The duration of larval period was shortened by Launaea arborescens, P. aquilinum and A. iva extracts, whereas R. raphanistrum and P. harmala extracts extend the larval period when compared to the control. Extracts of C. erythraea, P. harmala, A. iva and A. baetica inhibited F1 progeny production. Larvae possess three alpha-amylase isoforms as determined by SDS-PAGE. Larvae fed on treated diet had lower alpha-amylase activity than larvae feed on untreated diet. C. erythraea and P. harmala are the most potent extracts. These plant extracts could be useful to reduce seed damage caused by this pest species.  相似文献   

13.
目的:观察麦冬不同提取物对过氧化氢诱导的人脐静脉内皮细胞(HUVEC)间黏附分子-1(ICAM-1)和VEGF、Bcl-2表达的影响。方法:体外培养HUVEC,用过氧化氢(H2O2)制造HUVEC损伤模型。以四甲基偶氮唑蓝(MTT)比色法检测细胞存活数量,用流式细胞仪检测HUVEC表面ICAM-1的表达量;免疫细胞化学方法检测HUVEC的VEGF、Bcl-2的分布情况。结果:模型组较正常对照组细胞增殖活性明显降低(P〈0.01)。与模型组相比,经麦冬水提物、正丁醇提取物处理组细胞增殖活性明显增加(P〈0.05,P〈0.01)。流式细胞仪检测显示正丁醇提取物可降低过氧化氢增加的ICAM-1基因的表达。Bcl-2的表达,模型组明显低于正常对照组,而正丁醇组表达明显高于模型组(P〈0.01)。VEGF的表达,模型组明显高于正常对照组,麦冬水提物、正丁醇提取物处理组高于模型纽(P〈0.05,P〈0.01)。结论:麦冬提取物具有抗凋亡、促增殖、降低细胞间黏附分子-1表达的作用,尤以正丁醇提取物效果更为显著。  相似文献   

14.
目的探讨纳米银离子对细菌生物被膜(biofilm,BF)的空间结构的影响。方法采用摇床法,以纳米银离子含量不同的乙烯-醋酸乙烯酯(Ethylene-Vinyl acetate,EVA)塑料为细菌粘附载体,模拟体内铜绿假单胞菌(P.aeruginosa,PA)BF形成的微环境,建立体外BF模型;将培养3 d的空白标本分别在扫描电子显微镜(scanning electron microscopy,SEM)下及用FITC-ConA染色后荧光显微镜下观察不含纳米银EVA中BF的形成情况;将生长0.5、1、2、3、5 d的BF模型行SYTO9/PI染色,激光共聚焦扫描电镜(confocal laser scanning microscopy,CLSM)下摄取不同层面的图像,然后应用激光共聚焦显微镜TCS SP2自身具有的分析软件及ISA分析软件获得PAO1菌株BF的相关空间结构参数定量化数据。结果 (1)运用SEM及荧光显微镜的方法,在以不含纳米银EVA塑料为细菌粘附载体上培养3 d的标本中均观察到流线状的BF形成。(2)激光共聚焦显微镜TCS SP2自身具有的分析软件定量化分析显示,随着时间的延长,各含纳米银离子材料组PAO1菌株BF的平均厚度都呈先升高后降低的趋势,3天组都达最高值;纳米银离子的含量对BF厚度的影响差异无统计学意义(F=2.11,P>0.1),作用时间对BF厚度的影响差异有统计学意义(F=985.81,P0.05)。随着培养时间的延长,各含纳米银离子材料组PAO1菌株BF的AP值、ADD值无明显的变化趋势,同一时间组的含有纳米银离子材料组PAO1菌株BF的AP值都高于空白对照组的AP值;同一时间组的含有纳米银离子材料组PAO1菌株BF的ADD值都低于空白对照组的ADD值。各含纳米银离子材料组PAO1菌株BF的TE值随着时间的延长,都呈先升高后降低的趋势,2天组都为最高值;同一时间组的TE值随着含纳米银离子的增加都呈降低趋势。结论运用摇床法成功建立了体外PAO1菌株BF模型;纳米银离子对PAO1菌株BF空间结构有显著的影响。  相似文献   

15.
Bracken ferns (genus Pteridium) represent an ancient species complex with a natural worldwide distribution. Pteridium has historically been treated as comprising a single species, but recent treatments have recognized several related species. Phenotypic plasticity, geographically structured morphological variation, and geographically biased sampling have all contributed to taxonomic confusion in the genus. We sampled bracken specimens worldwide and used variable regions of the chloroplast genome to investigate phylogeography and reticulate evolution within the genus. Our results distinguish two major clades within Pteridium, a primarily northern hemisphere Laurasian/African clade, which includes all taxa currently assigned to P. aquilinum, and a primarily southern hemisphere Austral/South American clade, which includes P. esculentum and P. arachnoideum. All European accessions of P. aquilinum subsp. aquilinum appear in a monophyletic group and are nested within a clade containing the African P. aquilinum taxa (P. aquilinum subsp. capense and P. aquilinum subsp. centrali-africanum). Our results allow us to hypothesize the maternal progenitors of two allotetraploid bracken species, P. caudatum and P. semihastatum. We also discuss the biogeography of bracken in the context of the chloroplast phylogeny. Our study is one of the first to take a worldwide perspective in addressing variation in a broadly distributed species complex.  相似文献   

16.
Two morphotypes of bracken fern in the genus Pteridium Gled. ex Scop. occur in sub-Saharan Africa. The more common and widespread of these is assigned in contemporary systematic treatments to the European subspecies, P. aquilinum (L.) Kuhn ssp. aquilinum . We show that this African form is separable morphometrically and genomically from the European subspecies, and reinstate its earlier name P. aquilinum ssp. capense (Thunb.) C.Chr. The second African bracken, with a more localized tropical distribution mainly in the drainage basins of the Congo and Zambezi River systems, is confirmed as P. aquilinum ssp. centrali-africanum Hieron. ex R.E. Fr. We reject suggestions that this taxon be treated as a full species. Phenetic cluster analysis based on use of Arbitrarily Primed Polymerase Chain Reaction (A-P PCR) and Inter Simple Sequence Repeat (ISSR) fingerprinting of the nuclear genome provides evidence that the two African brackens are more closely related to each other than to other taxa, and sister to a grouping of the European sspp. aquilinum and pinetorum . The two African subspecies share solely with ssp. aquilinum a distinctive chloroplast haplotype carrying a 5-base direct repeat in the rps 4 –trn S region, confirming the close phyletic relationship between sspp. aquilinum , capense and centrali-africanum .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 311–321.  相似文献   

17.
SHEFFIELD, E., WOLF, P. G., HAUFLER, C. H., RANKER, T. A. & JERMY, A. C, 1989. Are-evaluation of plants referred to as Pteridiutn herediae (Colmeiro) Love & Kjellqvist. Based on perceived differences in morphology, chromosome number and habitat, specimens of Pteridiutn from southern Spain have been segregated by previous authors as a species distinct from Pteridium aquilinum , and called Pteridium herediae. However, type specimens of this taxon cannot be found. New collections of Pteridium from similar habitats in the area were examined and analysed in the present study and the results compared with those from British plants (P. aquilinum). The Spanish plants were not found to differ significantly from P. aquilinum morphologically, and all yielded chromosome counts (sporophytes, 104; gametophytes, 52) considered typical for the genus. Genotype frequency data obtained from isozyme electrophoresis of Spanish and British Pteridium yielded a genetic identity of 0.86; well within intraspecific distances found in other ferns.
These data indicate that there are currently no grounds for accepting that a form of Pteridium , distinguishable from P. aquilinum on the basis of differences in morphology, chromosome number, habitat or biochemistry, exists on the limestone soils of the Sierra de Cazorla region of southern Spain.  相似文献   

18.
目的:探讨长期异相睡眠剥夺对大鼠能量代谢及血清甲状腺素水平的影响。方法:采用小平台水环境法建立长期异相睡眠剥夺大鼠模型;检测其能量代谢变化;放射免疫法检测血清中甲状腺素水平。结果:睡眠剥夺后大鼠摄食量由(75.06±25.37)g/(d.kg)增加到(122.30±20.43)g/(d.kg),体重由(360.89±43.01)g减轻到(295.97±37.95)g,体温由(37.62±1.12)℃先升高到(39.00±0.87)℃后又降低至(37.72±0.84)℃,基础代谢率由(1.69±0.36)mlO2/(g.h)增加到(2.40±0.09)mlO2/(g.h)与对照组相比差异显著(P〈0.05);血清中游离三碘甲状腺原氨酸(FT3)水平由(3.38±0.88)pmol/L降低到(2.38±0.83)pmol/L,游离甲状腺素(FT4)由(14.62±3.62)pmol/L降低到(8.26±2.80)pmol/L与对照组相比差异显著(P〈0.05)。结论:长期异相睡眠剥夺可以显著影响大鼠的能量代谢和血清甲状腺素水平。  相似文献   

19.
顾万  邹穗怡 《蛇志》2014,(2):151-152,155
目的研究奥沙利铂对人子宫内膜癌细胞HEC-1A侵袭转移的影响。方法体外稳定培养HEC-1A细胞株系,用不同浓度奥沙利铂(40、80、160μg/ml)给药72h后,采用Transwell法测定奥沙利铂对HEC-1A侵袭能力的影响,重组基底膜试验测定奥沙利铂对HEC-1A粘附能力的影响,划痕试验检测奥沙利铂对HEC-1A迁移能力的影响。结果与未处理对照组比较,奥沙利铂(40、80、160μg/ml)明显抑制HEC-1A侵袭性,提高侵袭抑制率(P0.01),显著降低肿瘤细胞的迁移能力(P0.01),降低HEC-1A粘附程度(P0.01)。结论奥沙利铂有效抑制子宫内膜癌细胞继发性侵袭及转移,从而发挥抗癌作用。  相似文献   

20.
观察2型糖尿病大鼠不同时期肺组织谷氨酰胺果糖转移酶1(Gfat1)的表达情况.方法 SD大鼠随机分为正常对照组和模型组,对照组18只,模型组28只.模型组高脂饲料喂养2个月后,腹腔注射链脲佐菌素(STZ 15mg/kg)复制糖尿病模型,统计体重变化及空腹血糖值.RT-PCR方法检测造模成功后2周、4周和6周肺组织Gfat1 mRNA表达.结果 模型组大鼠体重增长较快,造模开始第28天,第42天,第56天和第70天高脂模型组与对照组体重差异有显著性(P<0.05).注射STZ的高脂模型组空腹血糖值较高(FBG≥10.0),和对照组比较,FBG差异有极显著性(P<0.01).糖尿病大鼠造模成功后2周,模型组肺组织Gfat1的表达低于对照组,与对照组比较差异无显著性(P>0.05),4周模型组Gfat1的表达高于对照组,模型组与对照组比较差异有显著性(P<0.05).6周模型组Gfat1的表达高于对照组,但模型组与对照组比较差异无显著性(P>0.05).结论 大鼠饲喂高脂饲料结合腹腔注射STZ可成功建立2型糖尿病大鼠模型;在不同时期2型糖尿病大鼠肺组织中,Gfat1表达水平发生改变.  相似文献   

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