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1.
坛紫莱多糖的分离纯化和结构分析(Ⅱ)   总被引:2,自引:0,他引:2  
对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白,冻干后得粗多糖,得率为8%。在粗多糖溶中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2,PP2经DEAE-纤维素、葡聚糖凝胶G200进一步纯化。经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品。通过红外光谱、气相色谱对PP2进行组成分析,再用化学方法测定其总糖,3,6-内醚-L-半乳糖及硫酸基的含量,分别为86.33%、5.425%和12.2%。最后通过高碘酸氧化,Smith降解等方法测定PP2的化学结构,结果表明,PP2由半乳糖、3,6-内醚-L-半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成,具有α,β型糖苷键,连接方式有(1→3)、(1→4)、(1→2)3种。PP1分子量通过凝胶过滤法初步测得为16.2万左右。  相似文献   

2.
莪术多糖的分离纯化   总被引:2,自引:0,他引:2  
研究莪术多糖分离纯化的最佳条件,优化莪术多糖的提取纯化工艺,为进一步探讨莪术多糖的生物活性奠定基础.莪术经热水提取,酒精沉淀,脱色,脱蛋白得粗多糖.粗多糖用50%、75%乙醇分级沉淀得2个级分CZ1、CZ2,进行DEAE-纤维素柱层析.调节DEAE-纤维素的pH值,比较洗脱曲线的不同.CZ1经DEAE-纤维素柱层析得到1个组分,CZ2在酸性、中性条件下层析得2个组分,在碱性条件下得1个组分,随pH升高,回收率降低,纯度增高.各纯化得到的多糖组分经纸层析、琼脂糖凝胶电泳鉴定为单一成分.实验证明,pH是影响层析的一个重要因素,因此莪术多糖的最佳纯化pH值为7.0.  相似文献   

3.
坛紫菜多糖的分离纯化和结构分析(Ⅱ)   总被引:1,自引:0,他引:1  
对广东产坛紫菜沸水提取多糖采用Sevag法脱蛋白 ,冻干后得粗多糖 ,得率为 8%.在粗多糖溶液中加入CTAB以沉淀除去酸性多糖PP1,超滤以纯化中性多糖PP2 ,PP2经DEAE 纤维素、葡聚糖凝胶G2 0 0进一步纯化 .经纸层析、凝胶过滤及紫外光谱分析鉴定为纯品 .通过红外光谱、气相色谱对PP2进行组成分析 ,再用化学方法测定其总糖 ,3,6 内醚 L 半乳糖及硫酸基的含量 ,分别为 86 .33%、5.4 2 5%和 12 .2 %.最后通过高碘酸氧化 ,Smith降解等方法测定PP2的化学结构 ,结果表明 ,PP2由半乳糖、3,6 内醚 L 半乳糖、甘露糖、葡萄糖、木糖和阿拉伯糖组成 ,具有α ,β型糖苷键 ,连接方式有 (1→ 3)、(1→ 4 )、(1→ 2 ) 3种 .PP1分子量通过凝胶过滤法初步测得为 16 .2万左右 .  相似文献   

4.
以蛹虫草菌丝体粗多糖为材料进行分离纯化及性质的研究.提取液浓缩用3倍体积乙醇沉淀,等电点Sevag法除蛋白,10%H2O2脱色,得到的粗多糖经DEAE-DE52纤维素柱层析,用0~0.2mol/L的NaCl洗脱,可以得到未完全分离的多糖.将此多糖经Sephadex-G200柱层析,用蒸馏水洗脱.将多糖用Sepharose CL-6B柱层析进行纯度鉴定,经验证是单一多糖.对多糖进行纸层析,证明组分是D-葡萄糖和D-半乳糖.用高效液相色谱法测定多糖分子质量为3.76×104ku.以昆明种小鼠对多糖进行生物活性研究,多糖对小鼠S180肉瘤抑制率达到71.92%.  相似文献   

5.
蕨麻水溶性多糖的提取及其单糖组分的分析   总被引:3,自引:0,他引:3  
本文采用热水提取、乙醇沉淀、a-淀粉酶法脱淀粉、链酶蛋白酶和Sevag法联合除蛋白,得到蕨麻多糖.对提取的蕨麻多糖进行了总糖含量及糖醛酸含量的测定.粗多糖(P1)总糖含量为41.8%,糖醛酸含量为11.1%.脱淀粉脱蛋白多糖(P2)总糖含量为39.4%,糖醛酸含量为35.9%.经纸层析和高效液相色谱分析,表明该多糖主要由阿拉伯糖、鼠李糖、葡萄糖、半乳糖、半乳糖醛酸组成,说明蕨麻多糖为酸性杂多糖.  相似文献   

6.
灰树花子实体多糖和菌丝体多糖的比较分析   总被引:8,自引:0,他引:8  
从灰树花 (Grifolafrondosa)子实体和菌丝体中提取分离得到子实体多糖F -D和菌丝体多糖M -D ,得率分别是 0 .5 9%、0 .31% ;F -D的糖、蛋白质含量为 6 4 .8%、15 .6 % ,M -D糖、蛋白质含量是 6 5 .9%、7.37% ;气相色谱分析单糖组成 ,F -D由岩藻糖、阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖组成 ,各单糖的摩尔比为 0 .9:0 .5 :1.3:5 .0 :2 .9:10 0 .0 ;M -D由鼠李糖、岩藻糖、阿拉伯糖、木糖、甘露糖、半乳糖、葡萄糖组成 ,各单糖的摩尔比为 5 .9:8.5 :3.2 :2 3.2 :6 .5 :11.7:10 0 .0 ;红外光谱图显示F -D和M -D约在 890cm- 1处有吸收 ,1H -NMR谱显示两者在 5mg/L以上均无吸收 ,13C -NMR谱显示两者在 10 5× 10 - 6 、86× 10 - 6 、和 71× 10 - 6 处均有吸收 ,提示F -D和M -D多糖中均存在 β(1→ 3)和 (1→ 6 )糖苷键。  相似文献   

7.
对条斑紫菜蛋白酶解获得的血管紧张素转换酶抑制肽(ACEI)进行纯化和结构鉴定,并研究了条斑紫菜ACEI肽体外贮存稳定性和对原发性高血压大鼠的降血压作用.结果表明:通过2步反相高效液相制备色谱纯化得到2种单一组分ACEI肽,经液质联用质谱分析肽序列分别为Cys-Ser-Asn-Arg和Pro-Cys-His-Trp,二者对血管紧张素转换酶半数抑制浓度分别为24.71和5.38 μmol·L-1;条斑紫菜ACEI肽不耐高温,在中性或酸性条件下较稳定;用分子质量小于3 ku条斑紫菜ACEI肽组分对原发性高血压大鼠灌胃后有显著降血压效果,且降血压幅度随灌胃剂量增大而提高.  相似文献   

8.
文章采用醇沉分级法来获取和纯化枳椇多糖,并研究各组分的理化性质及免疫调节活性。从枳椇肉质果柄中提取粗多糖,用蒸馏水洗脱过DEAE纤维素柱后进行分级醇沉,获得了醇沉组分HDP1-1、HDP1-2和HDP1-3,研究了其化学成分、单糖组成、分子量分布、红外吸收特征峰及其对巨噬细胞的免疫调节活性。结果表明,总糖质量分数分别为(97.26±0.17)%、(92.90±1.02)%和(95.48±2.45)%;HDP1-1是分子量为2 187kDa的均一性多糖,由半乳糖组成;HDP1-2和HDP1-3主要由葡萄糖、鼠李糖和半乳糖组成,其中HDP1-3还含有少量木糖;红外光谱分析表明各醇沉组分均具有多糖的特征吸收峰。免疫调节活性实验表明,HDP1-3在巨噬细胞增殖、NO产量和中性红吞噬实验中,比其他2个组分对巨噬细胞的刺激作用更强。  相似文献   

9.
牛舌菌(Fistulinahepatica)子实体经热水抽提,乙醇沉淀,蛋白酶法和Sevag法去蛋白后得粗多糖FHP.FHP经DEAE-纤维素和SephadexG-200柱进一步纯化得到牛舌菌多糖纯品FHP-2P.经测定该多糖为均一组分,相对分子质量为7.6×104.红外扫描呈现出典型的多糖吸收峰,并含有β-型糖苷连接键;紫外扫描无核酸和蛋白质的特征吸收峰.纸层析和气相色谱分析结果表明FHP-2P的单糖组成为D-葡萄糖、D-甘露糖、D-半乳糖和D-木糖,其摩尔比为13.9∶2.85∶3.25∶0.48.  相似文献   

10.
白沙蒿籽多糖的分离纯化及结构研究   总被引:1,自引:0,他引:1  
以白沙蒿籽为原料,经水提醇沉,酶法和Seveg法脱蛋白,乙醇分级沉淀,得到两种酸性多糖ASP1和ASP2.将ASP1和ASP2分别完全酸水解、高碘酸氧化、Smith降解后经高效液相色谱分析表明ASP1主要成分是木糖,含有少量葡萄糖和阿拉伯糖,数均分子量2.84×105,ASP2由葡萄糖、半乳糖、阿拉伯糖和甘露糖组成,摩尔比为2.1:1.3:1.0:1.4,数均分子量3.50×104,ASP1中糖苷键以1→3连接为主,ASP2中糖苷键以1→4连接为主,红外光谱及核磁共振光谱表明ASP1,ASP2中均含有糖醛酸为酸性多糖,且均含有α和β两种构型.  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
<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   

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