补料工艺对两株法夫酵母菌株产虾青素的影响

【目的】考察不同补料工艺对法夫酵母菌株生长和虾青素合成的影响。【方法】对法夫酵母JMU-VDL668和JMU-MVP14菌株在7 L罐中进行分批及分批补料培养; 同时, 测定发酵过程中生物量、虾青素和葡萄糖含量的变化。【结果】采用恒DO补料, 法夫酵母JMU-VDL668菌株获得的生物量最大(64.6 g/L), 是分批培养的2.2倍; 采用恒pH补料发酵, 虾青素的产量最高(20.6 mg/L), 是分批培养的1.5倍。与JMU-VDL668菌株不同, 虾青素高产菌株JMU-MVP14菌株采用恒pH补料, 获得生物量最大(48.5 g/L), 但虾青素产量大大降低(仅17.5 mg/L); 采用脉冲补料, 虾青素产量最高, 达到414.1 mg/L, 与分批发酵相比提高了200.2%; 采用恒DO补料, 生物量(38.5 g/L)和虾青素产量(403.2?mg/L)增加显著, 与分批发酵相比分别提高了133.1%和192.3%。【结论】不同补料工艺对法夫酵母菌株生产虾青素影响很大。其中, 采用恒pH补料工艺, 法夫酵母JMU-VDL668菌株可以获得最高的虾青素产量, 而采用脉冲补料工艺, 最适于法夫酵母JMU-MVP14菌株发酵生产虾青素。     

法夫酵母高密度培养及虾青素的高产研究*

本文对法夫酵母Phaffia rhodozyma的不同流加培养模式进行了研究。实验结果表明,采用指数流加,虾青素产率和细胞干重具有较大值,分别达到14.52mg/l和32.56g/l;其次是恒pO2流加和恒速流加培养,虾青素产率分别达到8.89mg/l和6.70mg/l; 恒pH流加方式更有利于法夫酵母细胞的生长(14.62g/l DCW)。但是,不同流加培养模式所得的μmax和qasta具有较大的差距。恒pH、恒pO2流加培养及间歇培养有较大值,分别为0.0613 h-1、0.056 h-1、0.053 h-1;指数流加的μmax较小。间歇培养中虾青素生成比率最大,qasta=0.048×10-3h-1。     

一株法夫酵母虾青素高产菌株的生产性能

为了评价虾青素高产菌株-法夫酵母JMU-MVP14的生产性能及建立虾青素高产发酵技术,通过测定糖、生物量、虾青素产量、总类胡萝卜素产量等发酵参数,用摇瓶试验对比了法夫酵母JMU-MVP14和出发菌株的差异,用7 L罐试验对比了pH值调控方式及补料培养基成分对发酵的影响,用1 m3罐试验评估了法夫酵母JMU-MVP14高密度发酵虾青素的产量水平。摇瓶发酵结果表明,法夫酵母JMU-MVP14虾青素及总类胡萝卜素的细胞产率分别达到6.01 mg/g及10.38 mg/g;7 L罐分批发酵试验结果表明,自动流加调     

补料分批法高密度培养凝结芽孢杆菌

研究在摇瓶条件下通过补加含有不同浓度的葡萄糖与酵母膏的料液及不同流加方式对凝结芽孢杆菌(Bacillus coagulans)TQ33菌体量和芽孢生成量的影响,确定了补料液中的葡萄糖与酵母膏比例为61(w/w),采用将葡萄糖浓度控制在3.0g/L～6.0g/L的流加方式进行高密度培养凝结芽孢杆菌.在5L自动发酵罐中进行补料分批培养,最终菌体浓度达到4.5×109cfu/mL,芽孢浓度为1.2×109cfu/mL,分别是分批培养的5.9倍和3.8倍.     

基于动力学模型的法夫酵母发酵生产虾青素的补料策略优化

对法夫酵母的不同补料发酵方式进行了研究.基于底物抑制模型,提出了一种优化的两阶段补料策略,用于法夫酵母产虾青素的高密度发酵.在发酵的延迟期和对数生长期早期,糖浓度控制在25 g/L左右,在此条件下,生物量可以达到最大,且时间缩短.在对数生长期后期及稳定期,糖浓度控制在5 g/L,虾青素的合成时间可以有效延长.与传统的补料方式相比,采用此补料策略取得了较好的发酵效果.发酵终点细胞干重达到23.8g/L,虾青素产量达到29.05 mg/L,分别比分批发酵提高了52.8%和109%.     

pH及流加葡萄糖对酵母分批发酵生产谷胱甘肽的影响

在5 L的发酵罐中研究了pH及流加葡萄糖对酵母分批发酵生产谷胱甘肽(GSH)的影响。实验考察了不同浓度的流加葡萄糖和不同的恒pH值的分批发酵对于酵母生产GSH产量的变化。实验结果表明,当pH值控制为5.0,流加葡萄糖流速为5g.L-1.h-1,连续流加30 h,可使GSH产量最高,与之前未流加葡萄糖和控制pH相比,其产量提高了6倍。     

红酵母类胡萝卜素形成的生理学研究

从数株红酵母中选出 1株产类胡萝卜素能力较强的红酵母RY 98(生物量、类胡萝卜素含量和产量分别为19.9g/L ,334 .8μg/ g和 6 .7mg/L) ;研究了该菌株产类胡萝卜素的最适营养与环境条件 ,获得了最佳的发酵生理学条件 :葡萄糖 40 g/L ,(NH4 ) 2 SO4 10 g/L ,酵母膏 3g/L ,蕃茄汁 2mL/L ,花生油 0 .5mL/L ,接种量 30mL/L ,初始pH 6 .0和通气量 (培养基装量 ) 4 0mL/ 2 5 0mL。在此初步优化的培养条件下 ,红酵母RY 98经 72h摇瓶发酵其生物量、类胡萝卜素含量和产量分别可达 2 6 .8g/L ,386 .9μg/ g和 10 .4mg/L ,依次比初筛中提高了 34 .7% ,15 .6 %和 5 5 .2 %。     

红酵母NZ-01发酵条件的优化

以红酵母菌株NZ-01为试验菌株,研究其发酵工艺与中试生产。采用摇瓶发酵优化的方式,研究培养基组分与发酵工艺条件对该菌发酵的影响,并进行中试放大生产。结果显示,该菌最适生长培养基组分为葡萄糖10g/L,蔗糖10g/L,酵母膏10g/L,牛肉膏2.5g/L;色素合成最适培养基组分为葡萄糖15g/L,蔗糖10g/L,酵母膏2.5g/L,牛肉膏5g/L。最适生长起始pH值为6.0,最适接种量为8%,生长周期为44h;最适色素合成起始pH值为7.0,最适色素合成接种量为8%,色素合成周期为48h。发酵优化后的色素产量3.88μg/mL较优化前1.71μg/mL提高了127%。中试产量达3.05μg/mL。红酵母菌NZ-01优化后的发酵条件可以应用于中试生产虾青素,有规模化生产应用潜力。     

红酵母类胡萝卜素高产菌株的筛选及其发酵生理学条件研究

从数株红酵母中选出了1株产类胡萝卜素能力较强的红酵母RY－98（生物量,类胡萝卜素含量和产量分别为19．9g/L,334.8ug/g和6．7mg/L);研究了该菌株产类胡萝卜素的最适营养与环境条件,获得了最佳的发酵生理学条件;葡萄糖40g/L,(NH4)2SO4 10g/L,酵母膏3g/L,蕃茄汁2mL/L,花生油0.5mL/L,接种量30mLL初始pH6.0和通气量（培养基装置040ml/250mL:,在此初步优化的培养条件下,红酵母RY－98经72小时摇瓶发酵其生物量,类胡萝卜素含量和产量分别可达26．8g/L,386.9ug/g和10．4mg/L,依次比初筛中提高了34．7％,15．6％,和55．2％。     

重组巴斯德毕赤酵母高密度发酵表达植酸酶

对巴斯德毕赤酵母的高密度发酵条件进行了试验,并根据摇瓶发酵的优化结果进行了补料方式的研究。在摇瓶发酵时,最佳种龄为16h,接种量为3％,甲醇的诱导浓度为15g／L,生长阶段最适pH为5．0,诱导阶段最适pH为5．5。在间歇补料、恒速补料、变速补料三种补料方式中以变速流加最优。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

Time of detection of recessive genes: effects of system of mating and number of examined individuals

Summary Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, Siete Cerros 66 and Penjamo 62, as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of Penjamo 62 in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.