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1.
紫芝茵丝体多糖含有多个多糖组分,其分子量分布范围很宽,用不同乙醇浓度先分级沉淀多糖,再用Sephaclex G-100葡萄糖凝胶柱分离纯化不同分子量的多糖组分.结果表明:50%乙醇浓度沉淀多糖含有单一多糖组分,60%乙醇浓度沉淀多糖主要含有三个多糖组分,70%乙醇浓度沉淀多糖主要含有二个多糖组分,85%乙醇浓度沉淀多糖含有一个多糖组分.  相似文献   

2.
红毛五加多糖的分离纯化和表观分子质量测定   总被引:2,自引:0,他引:2  
红毛五加经热水浸提,用Sevag法脱蛋白,经DEAE—cellulose 32离子交换层析和Sephacryl S-200HR凝胶层析纯化得到3个主要多糖组分:AHP-Ⅰ、AHP-Ⅱ、AHP-Ⅲ,经HPLC和Sephacryl S-300HR凝胶层析鉴定,3种多糖均为均一组分,HPLC测定AHP-Ⅰ、AHP-Ⅱ、AHP-Ⅲ的表观分子质量分别为:7.0kD、59.5kD和12.9kD,Sephacryl S-300HR凝胶层析进行验证,得到相似结果.  相似文献   

3.
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   

4.
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   

5.
云芝胞内多糖CVP-Ⅱ的分离与初步鉴定   总被引:2,自引:0,他引:2  
从液体发酵的云芝菌丝体中提取获得菌丝体胞内多糖,,经DEAE-Sepharose CL-6B洗脱分离出一种主要组分CVP-Ⅱ,该组分经凝胶层析显现单一峰,初步鉴定CVP-Ⅱ为较纯组分,对CVP-Ⅱ进行紫外分析,结果发现该组分呈现蛋白结合多糖的特征,从红外分析来看,明显呈现出多糖的官能团吸收.  相似文献   

6.
从海带根中提取纯化褐藻硫酸多糖   总被引:1,自引:0,他引:1  
海带根粉碎后,经过酶解,去除褐藻酸,得到酶解液;通过DE-41、DE-80离子交换柱层析,得到海带硫酸多糖(FGS)F1-F8的8种不同组分;再用Sepharose 2B凝胶柱层析纯化,获得层析纯F1-F8的FGS.我们初步测定了8种FGS的分子量、单糖组分及其摩尔比.FGS为一类含有鼠李糖、岩藻糖、木糖、甘露糖、半乳糖以及硫酸根的杂多糖.  相似文献   

7.
酶法提取百合多糖及其体外抗氧化活性   总被引:41,自引:2,他引:41  
研究了热水法及复合酶法提取百合多糖(LBP)的最佳条件, 对两种方法得到的多 糖的生物活性进行了比较分析. 发现复合酶法能显著提高百合多糖的提取率, 可达31.03% , 是热水法的2.85倍. 复合酶法提取的多糖在体外抗氧化活性如对O2 ·及·OH的抑制作用、 对H2O2诱导的人血红细胞氧化溶血 的抑制作用及人红细胞膜脂质过氧化的抑制作用均显著高于热水法提取的多糖. 经Sephadex G-75柱层析对粗多糖进行分离, 得到3种组分, 其中活性组分LBP-3主要存在于酶法提取 的多糖中, 测得该活性组分的分子量为13 400.  相似文献   

8.
本文对纤维素酶法从野木瓜中提取水溶性粗多糖的工艺进行系统的研究,通过正交试验确定了最佳酶法提取条件:提取温度50℃,pH值4.0,提取时间2.5h, 酶用量3%。粗多糖经蛋白酶与Sevage法相结合脱蛋白、大孔树脂脱色及水浴透析,得到野木瓜水溶性精多糖CCP, 再经DEAE-纤维素阴离子交换层析柱,得一种洗脱组分CCP1。纸层析和Sepharose Cl-6B色谱柱分析表明CCP1为多糖纯品;用苯酚-硫酸比色法测定该多糖的糖含量为97.3%;紫外光谱分析未见蛋白质(280nm)与核酸(260nm)的特征吸收峰;红外光谱分析具有典型多糖吸收峰。结果表明,CCP1是初次从该植物中提取分离出来新的均一多糖组分。  相似文献   

9.
杜氏藻中多糖的化学研究(Ⅰ)   总被引:1,自引:0,他引:1  
用0.2%稀碱溶液萃取杜氏藻提取出β-胡萝卜素后的残渣,经浓缩后用乙醇沉淀,得粗多糖,以Sevage法除去蛋白质,再经DEAT-纤维素及葡聚糖凝胶G-100柱层析,得杜氏藻多糖(简称PDS).多糖经薄层层析、纸层析、气相色谱及经甲基化后的色谱/质谱分析,获知有5种糖,即半乳糖、木糖、鼠李糖、葡萄糖、甘露糖,并测得各种糖的可能连接.  相似文献   

10.
程丽娜 《甘肃科技》2012,28(11):132-134
主要采用水提醇沉法提取红芪多糖,将该粗多糖中酸性多糖进行含量测定,以及用DEAE - Sepharose Fast Flow阴离子交换柱和732阴离子交换层析柱进行红芪酸性多糖的分离工艺研究,将不同层析方法得到的酸性多糖再经Sepharose 6B Fast Flow凝胶层析纯度分析.实验结果表明,DEAE- Sepharose Fast Flow阴离子交换柱和732阴离子交换层析柱可用于红芪酸性多糖的分离.  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.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<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   

20.
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