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2005年05月14日

【期刊论文】寡聚糖诱导悬浮培养红豆杉细胞生理态势的改变

李春, 元英进, 马忠海, 胡宗定

化工学报,2002,53(11):1133~1138,-0001,():

-1年11月30日

摘要

运用顺磁共振、电镜、能谱等手段研究了寡聚糖对红豆杉细胞氧化还原生。理态势的影响。结果表明,诱导前红豆杉细胞处于相对稳定的生长态势,细胞完整,细胞器发达;氧化还原电势较低,活性氧相关酶系统相对稳定, 细胞初生代谢旺盛,紫杉醇合成速率很低。诱导后红豆杉细胞向产物合成态势转移,SOD酶活性迅速提高,CAT和POD酶活被强烈抑制;细胞出现活性氧迸发,4h达最大值;细胞的氧化还原电势增高,细胞膜上离子通道被激活,H+和Ca2+ 内流,Cl-外流;液胞内出现大量含Ca2+离子的高电子致密区并呈规律性变化,培养环境碱化;细胞生长被抑制,紫杉醇合成速率升高,其产量提高了515倍,达7611mg·L-1。

真菌寡聚糖 红豆杉细胞 悬浮培养 生理态势 紫杉醇

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2005年05月14日

【期刊论文】发酵液的组成对纳滤分离谷氨酰胺的影响

李春, 刘元帅, 李书良, 王晓琳, 曹竹安

过程工程学报,2003,3(2),-0001,():

-1年11月30日

摘要

研究了谷氨酰胺发酵液中盐离子对纳滤分离提取谷氨酰铵的作用,系统地考察了操作温度和发酵液组成对纳滤分离透过特性的影响,确定了纳滤分离时发酵液最佳稀释倍数和操作温度。结果表明,二价阳离子通过改变膜面电荷密度对谷氨酸的透过特性产生很大影响,使其截留率降低了8%。发酵液中较高浓度的(NH4)2SO4使谷氨酸和谷氨酰胺的截留率和透过通量明显降低,但较高浓度的NH4Cl影响较小,这体现了纳滤膜对不同离子排斥力的差异。当发酵液稀释至谷氨酰胺浓度为1%,pH调至7时,发酵液中的其它盐离子和残糖因浓度较低而对纳滤分离影响不显著。

发酵液, 谷氨酰胺, 纳滤分离, 盐离子

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2005年05月14日

【期刊论文】Separation of l-glutamine from fermentation broth by nanofiltration

李春, Shu-liang Li, Chun Li*, Yuan-shuai Liu, Xiao-lin Wang, Zhu-an Cao

Journal of Membrane Science 222(2003)191~201,-0001,():

-1年11月30日

摘要

Separation of l-glutamine (l-Gln) from Gln fermentation broth by nanofiltration (NF) was investigated with NTR7450 NF membrane. The effects of various experimental parameters such as transmembrane pressure, pH and concentration of broth on the rejection of l-Gln and l-glutamate (l-Glu) showed that NTR7450 was able to effectively separate l-Gln and l-Glu when the appropriate conditions were chosen. Moreover, the rejection of l-Gln and l-Glu in a single amino acid solution was also studied with the variation of pH, concentration, and physicochemical parameters. It was demonstrated that deviations in the rejection of fermentation broth from a single l-Gln or l-Glu solution were mainly caused by the complex ionic composition of the real fermentation broth.

Nanofiltration, Amino acid, l-Glutamine, Physicochemical environment, Fermentation broth

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2005年05月14日

【期刊论文】A structured kinetic model for suspension cultures of Taxus chinensis var. mairei induced by an oligosaccharide from Fusarium oxysporum

李春, Chun Li, Ying-Jin Yuan*, Jin-Chuan Wu & Zong-Ding Hu

Biotechnology Letters 25: 1335~1343, 2003.,-0001,():

-1年11月30日

摘要

A structured kinetic model was established to describe the process of Taxol formation in suspension cultures of Taxus chinesis var. mairei induced by an oligosaccharide from Fusarium oxysporum. In this model, the role of intracellular starch as a storage carbon source had to be taken into account. Substrate uptake, culture growth, cell respiration, and secondary metabolites, predicted by the model, agreed with those obtained experimentally. The effective factors of oligosaccharide elicitation, ηe,j, defined as the ratio of the parameter values in the system with oligosaccharide to those in control, reflected the effects of the oligosaccharide on cell growth and Taxol production.

oligosaccharide,, plant cell culture,, structured kinetic model,, Taxol,, Taxus chinesis var., mairei

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2005年05月14日

【期刊论文】A double oxidative burst for taxol production in suspension cultures of Taxus chinensis var. mairei induced by oligosaccharide from Fusarium oxysprum

李春, Ying-Jin Yuan*, Chun Li, Zong-Ding Hu, Jin-Chuan Wu

Enzyme and Microbial Technology 30(2002)774~778,-0001,():

-1年11月30日

摘要

The effects of oligosaccharide from Fusarium oxysprum on secondary metabolisms in suspension cultures of Taxus chinensis var. mairei were investigated by detecting the oxidative burst (OB) signals using an Electron Paramagnetic Resonance (ESR) spectrometer. The oxidative burst signals induced by oligosaccharide gradually increased to a maximum at 4h. Phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO) activities were respectively 2 and 4 times higher than those of control, and large amount of phenolics were accumulated in culture medium. Two times of obvious increase in taxol production was observed, which was in accordance with the two times of elicitation of oxidative burst signals. The dependence of taxol production on the intensity of OB signals obeyed a modified Logistic curve. It was inferred that the syntheses of the side chain and nucleus of taxol were enhanced at low and high intensities of OB signals, respectively.

Oligosaccharide, Fungus, Oxidative burst, Taxus chinensis var., mairei, Taxol, Suspension culture

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    石河子大学,新疆

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