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1.
高产谷氨酸菌S9114的选育及生产实绩   总被引:2,自引:0,他引:2  
以天津短杆菌(Brev.tianjin)T6-13出发,经紫外线、亚硝基胍用原生质体等诱变处理,选育出S9114菌株,具有耐高糖、耐高谷氨酸,不利用谷氨酸和产酸率高的特性。摇瓶产酸最高达96.9g/L,比原出发菌提高50%。经工艺条件优化,在20m3发酵罐最高产酸92.3g/L(转化率56.5%)。在60m3发酵罐连续10批平均产酸82.1g/L,转化率48.74%、在1500升发酵罐进行高生物素添加青霉素流加糖的工艺实验,最高产酸达98.7g/L,转化率52.2%,周期26小时。  相似文献   

2.
以短小芽孢杆菌为出发菌株 ,经过硫酸二乙酯和原生质体紫外诱变 ,定向选育出一株稳定的核糖生产菌 TJ3,该菌株具有莽草酸营养缺陷、耐高糖、以核糖为唯一碳源不生长等遗传标记。在发酵条件试验中 ,采用均匀设计理论 ,利用微机对试验数据进行统计处理 ,确定出以葡萄糖为原料直接发酵生产核糖的优化配比。在最适培养条件下 ,摇瓶发酵平均产核糖 30 .12 mg/m L  相似文献   

3.
谷氨酸生产菌的选育   总被引:6,自引:0,他引:6  
研究代谢调节突变株的选育方法.以北京棒杆菌Q-72为出发菌株,经紫外线诱变,筛选能在以琥珀酸为唯一碳源的培养基上生长良好的菌株,强化CO2固定反应.突变株UH62的产酸率和转化率分别比出发菌株提高1.45%和9.1%.  相似文献   

4.
以钝齿棒杆菌T6-13为出发菌,采用甘氨酶-青霉素G-溶菌酶处理其细胞,酸处理10小时制备的原生质体用激光辐照5分钟,挑取再生后菌落进行筛选,选育出二株高产菌5-20和5-21,最高产酸率分别为9.79%和9.65%,最高转化率分别为69.95%和68.96%,比出发菌提高44.83%和42.70%;5-20菌株在3万升大罐中试生产9罐,平均产酸6.79%,平均转化率为52.06%.  相似文献   

5.
本文采用自然界直接分离法从不同来源土壤中筛选谷氨酸产生菌,经产酸测定、噬菌体抗性检查,筛选出25株抗噬菌体产谷氨酸菌株,其中有2株产酸率在3.0%以上。  相似文献   

6.
经化学诱变,通过改变谷氨酸棒杆菌B1代谢途径,筛选出以甘油、丙酮酸和高丝氨酸为碳源的营养缺陷型,该突变菌株B10的产酸率和转化率分别比出发菌株高18.097%和15.56%.  相似文献   

7.
谷氨酸生产菌的诱变育种   总被引:1,自引:0,他引:1  
经化学诱变,通过改变谷氨酸棒杆菌B1的代谢途径,筛选出以琥珀酰CoA和乙醛酸为碳源的营养缺陷型,该突变菌株B4的产酸率和转化率分别比出发菌株高11.1%和8.7%.  相似文献   

8.
甘油是国防和民用工业的一种重要原料,日前市场供需矛盾突出。耐高渗酵母发酵法制取甘油是解决这一供求矛盾的有希望的途径,而高产菌株选育是该途径的基础。我组1987年从广西自然环境中筛选获得一株产甘油的菌种GW-11。本文是通过对该菌株的培养基组成及培养条件的试验。以获得最佳发酵条件,并对其甘油生产性状进行考察。结果表明:优化发酵条件与原试验条件相比,该菌发酵甘油产率由原8%提高到14.0%,对糖转化率由原来的40%,提高到46.7%,GW—11是一株具有潜在工业生产价值的耐高渗的甘油发酵生产菌。  相似文献   

9.
微生物发酵果渣蛋白饲料研究I.菌种选育及理化性质测定   总被引:2,自引:0,他引:2  
经土壤分离、纯化、筛选到2株耐高酸、高渗透压、高含水量生长环境、菌体蛋白含量40%以上的菌株,经鉴定为产朊假丝酵母(1号)、黑曲霉(2号)。通过混合发酵果渣结果表明,果渣中果胶、高酸高糖被转化,蛋白质含量大大提高。该菌株适合应用于大生产。  相似文献   

10.
经土壤分离、纯化、筛选到2株耐高酸、高渗透压、高含水量生长环境、菌体蛋白含量40%以上的菌株,经鉴定为产朊假丝酵母(1号)、黑曲霉(2号)。通过混合发酵果渣结果表明,果渣中果胶、高酸高糖被转化,蛋白质含量大大提高。该菌株适合应用于大生产。  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.
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  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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