灵芝真菌发酵胞外多糖反馈抑制的初步研究

探讨了灵芝胞外多糖自身反馈抑制作用。在摇瓶中考察了灵芝真菌发酵菌丝体生长、胞外多糖(EPS)和胞内多糖(IPS)合成的动态过程。在培养168h时，生物量达到最大值3．18g／L(干重)，培养216h时，胞外多糖达到最高浓度1．24g／L，EPS和生物量的变化趋势大致呈正相关。在摇瓶培养基中添加同源胞外多糖，以浓度梯度实验法考察培养基中的同源胞外多糖浓度对灵芝真菌发酵胞外多糖产量的影响，结果表明：培养基中添加的同源胞外多糖浓度高于0．59g/L时，EPS的产生受到明显抑制，其趋势是随着培养基中同源灵芝胞外多糖浓度的增加，反馈抑制作用逐渐增强，当培养基中添加的同源胞外多糖浓度高于2．34g/L时，菌丝的生长和胞外多糖的产生完全受到抑制。     

天麻醇提物对灰树花胞外多糖单糖组成和生物活性的影响

天麻醇提物参与灰树花液体发酵体系,检测所得胞外多糖的单糖组成变化,研究天麻醇提物对灰树花胞外多糖生物活性的影响。利用高效液相色谱对4种胞外多糖样品进行单糖组成分析,采用小鼠巨噬细胞(RAW264.7)活化模型、人肝癌细胞(HepG 2)模型对灰树花胞外多糖生物活性进行检测。实验结果表明灰树花粗多糖样品主要由葡萄糖、甘露糖及少量的半乳糖等单糖构成;经纯化的胞外精多糖由甘露糖、鼠李糖、葡萄糖、半乳糖、阿拉伯糖、岩藻糖等单糖构成,单糖物质的量比依次为13.8∶3.9∶5∶3.7:1∶1.7,而添加天麻醇提物的胞外精多糖单糖组分物质的量比为12.7∶3.2∶5.6∶3.5∶1∶1.6。通过灰树花胞外多糖对小鼠巨噬细胞活化实验的结果可知,添加天麻醇提物的胞外精多糖对巨噬细胞有明显的活化作用,胞外精多糖、添加天麻醇提物制备的胞外粗多糖对巨噬细胞有一定的活化作用,胞外粗多糖对巨噬细胞无明确的活化作用。通过体外实验检测,4种多糖样品对人肝癌细胞HepG 2无抑制作用。添加天麻醇提物对灰树花胞外多糖单糖组分含量产生明显变化,但并未使灰树花多糖产生新单糖;添加天麻醇提物能提高灰树花胞外多糖对巨噬细胞的活化作用。     

不同环境因子对爪哇伪枝藻分泌胞外多糖的影响

以一种从荒漠土壤中分离的典型丝状蓝藻——爪哇伪枝藻为材料,在实验室条件下研究了温度、盐度、pH和培养时间对爪哇伪枝藻胞外多糖分泌的影响.结果表明:随培养温度升高,伪枝藻胞外多糖分泌量逐渐升高,在35℃时达到最大值;在一定盐度范围内,胞外多糖分泌随盐度的增大而增大;pH在7.5时,胞外多糖产量显著高于酸性和碱性条件下的胞外多糖产量;随着培养时间延长,伪枝藻胞外多糖分泌逐渐增大.     

Lachnum YM328多糖发酵条件优化及抗氧化性

文章在碳源、氮源、金属离子和发酵时间4个单因素试验的基础上,利用正交试验法对Lachnum YM328胞外多糖发酵条件进行了研究,得出最优发酵条件为:ρ(葡萄糖)=20 g/L,ρ(酵母膏)=5 g/L,ρ(硫酸锰)=0.075 g/L,25 ℃下培养10 d;该条件下YM328胞外多糖产量为1.895 mg/mL,相对于优化前提高了36.27%;通过测定其胞外多糖(EPS)对·OH、NO-2的清除作用来研究YM328胞外多糖的抗氧化性;结果表明,YM328胞外多糖对·OH、NO-2均具有明显的清除作用,抗氧化性随着多糖质量浓度的增加呈增强趋势.     

富硒金针菇发酵液中胞外多糖的提取与分析

通过对富硒金针菇发酵液中胞外多糖的提取与分析,结果表明,加低浓度的硒可提高金针菇发酵液中粗胞外多糖的提取量和纯胞外多糖含量。     

拟康氏木霉产胞外多糖的分离纯化及组成初步研究

以拟康氏木霉（Trichoderma pseudokoningii SDTP1）产胞外多糖粗品为材料,经木瓜蛋白酶-Sevag法除蛋白、凝胶柱层析分离纯化,得到一种水溶性的拟康氏木霉产胞外多糖纯品（TPP-0）,并研究了其单糖组成.采用紫外光谱和红外光谱法对拟康氏木霉产胞外多糖进行了定性分析.结果表明,拟康氏木霉产胞外多糖具有多糖特征性的紫外和红外吸收峰 高效凝胶渗透色谱法测定结果表明,拟康氏木霉产胞外多糖的峰值分子量为1.8×104 采用气相色谱法测定拟康氏木霉产胞外多糖中单糖的种类和构成比例,结果表明,拟康氏木霉产胞外多糖主要由鼠李糖、葡萄糖、半乳糖等3种单糖组成,含有葡萄糖醛酸,并计算出3种单糖的摩尔组成比例.     

金针菇液体深层发酵多糖的提取与测定

金针菇液体深层发酵醪中,母液和菌丝体内分别含有胞外多糖、胞内多糖,在母液中加入一定体积９５ ％ 乙醇,得到胞外粗多糖;菌丝体烘干后,粉碎过筛,水浴提取胞内粗多糖。采用蒽酮比色法测定粗多糖中纯多糖的含量。     

海洋浮游硅藻胞外多糖研究进展

海洋浮游硅藻胞外多糖是其在生长过程中向外界环境所分泌的胞外产物中的一种,在海洋生态系统和海洋生物制药业中发挥着重要作用.本文对海洋浮游硅藻胞外多糖生物量的影响因素,胞外多糖的提取、分离和纯化方法,胞外多糖的成分分析与结构修饰及其药理学活性研究等进行了综述,并展望其在海洋生物制药方面的应用前景.     

天然水生物膜胞外多糖和胞外蛋白吸附镉的特性

研究了长春市南湖天然水环境中生物膜优势菌种胞外多糖和胞外蛋白对镉的吸附特征及其影响因素.结果表明,胞外多糖和胞外蛋白对镉的吸附过程符合Langmuir和Freundlich热力学等温方程,胞外多糖和胞外蛋白对镉的动力学吸附特征符合Langmuir-Hinshelwood方程的一级反应模式.而铅的存在会影响对镉的吸附.     

新型深海中温菌Wangia profunda（SM-A87）胞外多糖对对硝基苯胺的吸附研究

采用深海中温菌Wangia profunda（SM-A87）的胞外多糖对对硝基苯胺进行吸附试验。分别用热分析仪、FTIR和Zeta电位仪对胞外多糖进行表征分析,并研究了吸附时间、胞外多糖用量、pH和温度等方面对其吸附规律的影响。结果表明：胞外多糖可有效去除水中的对硝基苯胺。20℃时,0．1g／L的SM-A87胞外多糖吸附处理50mL初始浓度为15mg／L的对硝基苯胺水样120min后,对硝基苯胺的最大吸附率可达91％;Langmuir、Freundlich、Redlich-Peterson等温方程和准二级动力学方程均能较好地描述SM—A87胞外多糖吸附对硝基苯胺的热力学及动力学过程,由Langmuir方程得到SM—A87胞外多糖对对硝基苯胺的最大吸附量为769．2mg／g（30℃）。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<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