转基因鱼腥藻培养中培养液吸光度与生物量的关系

对转基因鱼腥藻Anabaena sp.PCC7120,培养液的吸光特性进行了研究,在可见光范围内,有5个吸收峰,波长分别为345nm,410nm,440nm,635nm,685nm,其中440nm是最大吸收波长,一定稀释度范围内,在各波长下,培养液中藻干重与吸光度均成正比,但不同培养基其干重－吸光度标准曲线不同,实验得到不同培养基的标准曲线,证明可以用比浊法测定转基因鱼腥灌培养过程的生物量。     

一种使用酶标仪快速测定细菌素效价的方法

目的建立快速测定细菌素效价的方法。方法以Nisin为参照物,利用酶标仪测定指示菌吸光度值。结果确定了在指示菌接种量为10%和细菌素作用时间为8 h 2个测定参数条件下,样品效价检测值的相对标准偏差在5%以下。结论所建方法快速、准确,适合检测菌所产细菌素的研究。     

NADH依赖型酶活性检测方法的建立

目的:建立一种NADH依赖型酶活性检测的方法。方法:将FDH、LeuDH串联克隆到表达载体pET-22b(+)中,转化至E.coli,并向培养液中分别添加去离子水、甲酸胺、三甲基丙酮酸,反应一段时间后,检测NADH的吸光度。同时通过测定氨气的产生判断FDH活性;通过薄层层析检测判断LeuDH活性;比较NADH吸光度测定结果与常规方法结果是否一致。结果:通过测定氨气的产生,证明FDH具有活性;此时NADH吸光度上升亦说明FDH具有活性;两种方法结论一致。薄层层析检测,生成叔亮氨酸,证明LeuDH具有活性;此时NADH吸光度下降亦说明LeuDH具有活性;两种方法结论一致。结论:通过检测菌体内部NADH吸光度的变化检测NADH依赖型酶活性的方法可行。     

落叶松林土壤溶液吸光度与土壤碳、氮含量的相关性

通过4个土壤深度100个样品14个波长(250、254、260、265、272、280、285、300、340、350、365、400、436和465 nm)土壤溶液吸光度值和土壤碳(可溶性碳DOC、全碳SOC)、土壤氮(可溶性氮DON、全氮SON)的测定,旨在探讨土壤溶液吸光度指示土壤碳氮指标的可行性及土壤深度对其可能影响。结论如下:(1)表层土壤和深层土壤吸光度值均随波长增加而指数下降,但表层土壤吸光度值较高,下降速度较快,较低波长更有利于区分表层和深层土壤溶液吸光度差异;和深层土壤相比,表层0～20 cm土壤SOC、DON和SON与不同波长吸光度有更好的相关性,但DOC与不同波长吸光度的相关性表层和深层差异较小;(2)250～300 nm的8个吸光度值具有高度相关性,它们在分析土壤溶液吸光度变化时具有等效性;基于所有数据的拟合分析发现,低波长(如254 nm)吸光度与土壤SOC、DON和SON相关性最高(R2=0.53～0.59),而更高波长(340 nm及以上)相关性明显降低。但DOC与254、340、365和400 nm吸光度相关性相差不大(R2=0.25～0.33)。这些发现说明,土壤溶液吸光度值,特别是低波长(250～300 nm)可以表征落叶松林土壤碳、氮相关指标的变化,但是需要考虑不同碳氮指标以及不同土层之间的差异。     

光合细菌培养条件优化的研究

摘要：目的 对光合细菌的培养条件进行优化,优选出更合适的培养基及光合细菌的初始接入量。方法 采用正交试验设计研究培养基中乙酸钠、硫酸铵和酵母膏3个因子对光合细菌生长的影响,以及考察5%、10%、15%和20%不同接菌量的影响,通过测定波长660 nm下菌液的紫外吸光度从而体现光合细菌的生长状况。结果 乙酸钠4.0 g、硫酸铵0.5 g、酵母膏2.0 g为培养基的优化配方,10%的接菌量为最佳。其中乙酸钠对光合细菌生长影响最大。结论 本研究为快速培养高活性的光合细菌奠定了理论基础。     

野生软枣猕猴桃总黄酮含量的测定

利用分光光度法,测定了软枣猕猴桃中总黄酮的含量,建立了芦丁浓度-吸光度关系的回归方程.     

微生物法测定食品中泛酸的含量

利用植物乳杆菌（ATCC8014）对泛酸的含量在一定条件下成线性关系,通过吸光度测定细菌繁殖浓度,可间接测定食物样品中泛酸的含量,并检测其回收率。结果表明标准曲线在10—100ng范围内线性关系良好,批内相对标准差（RSD）为2．1％-4．3％,批间测定RSD为2．7％-4．1％,回收率为88．4％～100．5％,达到了较好的分析效果。     

制备复合生长因子的缓释微球并考察其对细胞的影响

目的:制备复合碱性成纤维细胞生长因子的可降解缓释微球,考察其生物活性保存情况,以及其对上皮细胞的作用。方法:采用改良的乳化冷凝法交联制备明胶缓释微球,将其加入上皮细胞的培养液中,用细胞计数法、四甲基偶氮唑盐微量反应比色法(MTT法)测定细胞增殖情况。结果:缓释微球平均粒径12.36±3.56μm;培养1 d后各组细胞计数、吸光度(D)值差异均无显著性意义;5d后,缓释微球组细胞计数、吸光度(D)值明显高于对照组;7 d后,缓释微球组值仍高于其它组,但差异无显著性意义。结论:复合生长因子的缓释微球制备工艺简便,成球性好;能较长时间持续释放活性生长因子,明显促进细胞增殖。     

测定菌体浓度的简便方法

为了简便地测定测定JIS L 1902标准所规定的菌液浓度,以单位体积菌落数与吸光度(ABS值)的相关性,制成标准曲线,利用标准曲线快速准确地判断菌液浓度。     

黑斑蛙过氧化物酶活性测定条件的研究

本文报道了测定黑斑蛙过氧化物酶活力的两套方法.应用细胞组织化学的方法,对黑斑蛙的肝组织过氧化物酶的原位染色,以显示过氧化物酶在细胞中的分布.此外,还探讨了一种新的过氧化物酶活性检测方法,以联苯胺为底物,利用分光光度法测定反应液的吸光度,以吸光度的变化速率来表征过氧化物酶的活力.通过试验确定了该方法适宜的工作条件,包括酶浓度、温度、pH值等,得到酶活性变化的相关数据.     

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.     

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.     

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.     

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.     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.     

Specificity of action of piperidylcholine derivatives as substrates of cholinesterases of various origin

The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.