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1.
南海红树林内生真菌No.B4代谢产物研究   总被引:1,自引:1,他引:0  
首次对南海红树林内生真菌No.B4的代谢产物进行研究,从该菌的培养液中分离得到6个环二肽化合物,利用波谱技术确定其结构分别为环(亮氨酸-丙氨酸)(1)、环(亮氨酸-甘氨酸)(2)、环(脯氨酸-丙氨酸)(3)、环(苯丙氨酸-丙氨酸)(4)、环(苯丙氨酸-甘氨酸)(5)和环(苯丙氨酸-苯丙氨酸)(6).  相似文献   

2.
柳珊瑚共生细菌Bacillus subtilis发酵液化学成分研究   总被引:3,自引:0,他引:3       下载免费PDF全文
采用多种常规柱色谱和高效液相色谱分离技术,运用理化和波谱分析方法,对柳珊瑚共生细菌Bacillus subtilis的化学成分进行分离鉴定,并对分离得到的化合物进行抑菌活性测试和抗污损生物幼虫附着活性测试.结果分离得到7个环二肽类化合物,依次为环(S-脯氨酸-甘氨酸),环(S-脯氨酸-R-亮氨酸),环(4-羟基-脯氨酸...  相似文献   

3.
海洋细菌Bacillus Marinus化学成分分离和结构鉴定   总被引:1,自引:0,他引:1  
研究Z3-1号海洋细菌bacillus marinus发酵液的化学成分.利用硅胶、Sephadex LH-20柱色谱及重结晶等方法进行分离纯化,根据理化性质和^1H-NMR,^13C-NMR等波谱数据进行结构鉴定.得到8个化合物,分别鉴定为环(甘氨酸-脯氨酸)二肽、环(丙氨酸-脯氨酸)二肽、环(亮氨酸-脯氨酸)二肽、对羟基氧代吡啶、尿嘧啶、胸腺嘧啶、β-谷甾醇和尿素.以上化合物均为首次从该种细菌发酵液中分离得到.  相似文献   

4.
研究中华剑角蝗肠道内生真菌Penicillium oxalicum的次级代谢产物.通过溶剂提取法和多种色谱方法分离单体化合物,并利用现代波谱技术和理化性质进行结构鉴定.分离并鉴定了9个化合物,分别为1,10-dihydroxy-8-methyl-dibenz[b,e]oxepin-6,11-dione(1),大黄酚(2),柳胺酚(3),邻乙酰氨基苯甲酸(4),3,5-bis-(4-hydroxyphenyl)-pyridine(5),对羟基苯乙酰胺(6),烟酸(7),环(丙氨酸-异亮氨酸)(8),环(丙氨酸-亮氨酸)(9).所有化合物均为首次从该属菌种中分离得到.  相似文献   

5.
为研究杜鹃兰假鳞茎中的化学成分,利用正相硅胶柱色谱、葡聚糖凝胶Sephadex LH-20、反相制备液相色谱对其进行了分离纯化,并通过1H NMR和13C NMR波谱技术进行了结构鉴定.结果表明:从乙酸乙酯层中分离获得了5个化合物,分别鉴定为1-(4-羟苄基)-2,7-二羟基-4-甲氧基菲(I),3',5-二羟基-2-(p-羟苄基)-3-甲氧基联苄(II),2,7-二羟基-4-甲氧基-9,10-二氢菲(III),2,7-二羟基-1-(p-羟基苄基)-4-甲氧基-9,10-二氢菲(IV),4-羟基-2-甲氧基苯-1-O-β-D-吡喃葡萄糖(V),化合物IV~V为首次从该植物中分离获得.  相似文献   

6.
研究青龙衣的化学成分及抗肿瘤活性.利用硅胶柱色谱和开放ODS柱色谱等分离技术从青龙衣的95%乙醇提取物中分离得到了11个化合物,通过理化性质、波谱数据分析等方法,鉴定了全部化合物结构.采用MTT法,选取人胃癌细胞株(SGC7901),人肝癌细胞株(Hep G2),人肺腺癌细胞株(A549),乳腺癌细胞株(MCF7),结肠癌细胞株(Lo Vo)对化合物体外抗肿瘤作用进行筛选.从青龙衣中分离鉴定了11个化合物,分别为正二十九烷醇(nonacosanol)(1),[1-(4'-甲氧基苯基)-7-(3'-甲氧基,2'-羟基苯基)-3',4'-环氧-3-庚酮[3',4'-epoxy-1-(4'-methoxylphenyl)-7-(3'-methoxyl-2'-hydroxyphenyl)-heptane-3-one](2),正三十一烷醇(hentriacontanal)(3),1-(4'-羟基苯基)-7-(3'-甲氧基-4'-羟基苯基)-庚烷-3-醇[1-(4'-hydorxyphenyl)-7-(3'-methoxy-4'-hydorxyphenyl)-hepta-3-ol](4),4,6-二羟基-3,4-二氢-1-萘酮(4,6-dihydroxy-3,4-dihydro-naphthalenone)(5),胡桃醌(5-hydroxy-1,4-naphthoquinone)(6),β-谷甾醇(beta-sitosterol)(7),齐墩果酸(oleanolic acid)(8),香草酸(vanillic acid)(9),槲皮素(quercetin)(10),香草醛(vanillin)(11).化合物5、10对肿瘤细胞均有很强的生长抑制作用,IC50≤35μmol/L.化合物8对肿瘤细胞有较强的生长抑制作用,IC50≤58μmol/L.化合物2、3、6和7对个别肿瘤细胞有作用,其他化合物对肿瘤细胞没有生长抑制作用.11个化合物均为已知化合物,其中化合物1,3,10,11为属内首分,化合物5、8和10均具有较显著的抗肿瘤活性.  相似文献   

7.
采用硅胶柱色谱、Sephadex LH-20柱色谱、RP-18柱色谱方法对水青树(TetracentronsinenseOliv.)茎干进行了成分分离纯化,并利用UV、NMR、MS等波谱光谱方法对化学成分进行结构鉴定.共从水青树乙酸乙酯与正丁醇萃取部分中分离并鉴定了15个化合物,分别为2-羟基-5-(2-羟乙基)苯β-D-葡萄糖甙(1),2,6-二甲氧基-4-羟基苯1-O-β-D-吡喃葡萄糖甙(2),3,5-二甲氧基-4-羟基苯1-O-β-D-吡喃葡萄糖甙(3),丁香酸β-D-葡萄糖酯(4),丁香酸4-β-D-葡萄糖甙(5),甲氧基四氢醌-4-β-D-葡萄糖甙(6),甲氧基四氢醌-1-β-D-葡萄糖甙(7),对-羟基肉桂酸(8),β-乙酰鼠李糖甙(9),α-乙酰鼠李糖甙(10),(+)-儿茶素(11),羽扇醇(12),3β,20-羽扇二醇(13),白桦子酸(14),齐墩果酸(15).除化合物11-13和15外,其余化合物均为首次从该植物中分离得到.  相似文献   

8.
土家族药独蒜兰的化学成分研究   总被引:1,自引:0,他引:1  
采用正相硅胶柱色谱、葡聚糖凝胶Sephadex LH-20、反相制备液相色谱等手段进行分离纯化,并通过1H-NMR、13C-NMR等波谱技术进行结构鉴定,结果从乙酸乙酯层中分离得到了6个化合物,分别鉴定为bulbocol(1),coelonin(2),β-胡萝卜苷(3),间羟基苯甲酸(4),5-羟甲基糠醛(5),3-羟基苯丙酸(6),其中化合物3、4、5、6为首次从该植物中分离得到.  相似文献   

9.
为研究牛奶子(Elaeagnus umbellata Thunb)的药效物质基础,利用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、MCI柱色谱及半制备高效液相色谱对其枝叶化学成分进行分离纯化,结合理化性质和波谱数据对所得化合物进行结构鉴定.从牛奶子枝叶中分离得到16个化合物,分别鉴定为:4-羟基-4-(3-氧代-1-丁烯基)-3,5,5-三甲基环己-2-烯-1-酮(1),(3S,5R,6S,7E)-5,6-环氧-3-羟基-7-大柱香波龙烯-9-酮(2),(6R,7E,9R)-9-羟基-4,7-大柱香波龙二烯-3-酮(3),黑麦草内酯(4),2α,3α,23-三羟基-12-烯-28-熊果酸(5),2α,3α,23-三羟基-3,23-异亚丙基二氧基乌苏-12-烯-28-酸(6),2α-羟基熊果酸(7),熊果酸(8),白桦脂酸(9),3-羟基-1-(3-羟基-4-甲氧基苯)-1-丙酮(10),pinoresinol(11),丁香脂素(12),lariciresinol(13),紫云英苷(14),β-谷甾醇(15),胡萝卜苷(16).除化合物14和15外,其余化合物皆为首次从该植物中分...  相似文献   

10.
通过多种色谱分离方法对角果木根部真菌Fusarium sp.JG13代谢产物的化学成分进行研究,从其发酵液中分离得到五个化合物.利用波谱分析等手段分别鉴定为胸腺嘧啶(1),L-焦谷氨酸甲酯(2),邻苯三酚(3),5,7-二羟基-6,8-二甲氧基-2-甲基色原酮(4),腺苷(5).所有化合物均为首次从角果木真菌发酵产物中分离得到.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

19.
20.
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has  相似文献   

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