宣木瓜中黄酮的提取分离及含量的测定

从宣木瓜中提取总黄酮,并测定其含量.考察了回流提取、超声提取、微波提取等样品处理方法,用比色法测定宣木瓜中总黄酮含量.微波提取方法最好,芦丁在10～60μg/mL范围内具有良好的线性关系,r=0.9996;相对标准偏差为2%～3%,回收率在95%～98%之间.宣木瓜在7月下旬黄酮的含量最高,为5.93g/kg.     

中药香薷不同部位总黄酮及3种主要黄酮成分含量分析

中药材中活性成分的含量是中药品质优劣的关键指标。本文建立了香薷中总黄酮和3种主要黄酮的分析方法,探索不同部位黄酮含量的差异,为香薷黄酮类成分的开发利用奠定基础。结果表明优化后的分光光度法对香薷总黄酮测定具有专一性、稳定性。高效液相色谱测定木犀草素、芹菜素和黄芩素-7-甲醚的方法在测定范围内表现出良好的线性关系（r＞0.999）;方法的回收率在98.77%~102.13%之间,RSD均小于5%;不同部位总黄酮的含量由高到低依次为：苞＞尖＞茎＞根,且江西产香薷总黄酮的含量高于浙江产的香薷。这提示在工业生产上提取香薷黄酮类物质时尽量选择道地药材,同时可考虑弃去根部及茎的下端,以便提高浸提效率,增加经济效益。本试验建立的香薷中总黄酮和游离黄酮的测定方法准确、稳定,明确了香薷中总黄酮主要富集在花苞及附近,为进一步提高香薷资源的开发利用提供了理论依据和科学指导。     

赶黄草总黄酮树脂精制工艺与检测方法

本研究以总黄酮吸附量和解析率为检测指标,结合动态洗脱考察结果,考察11种树脂对赶黄草总黄酮的富集精制能力。优化树脂类型,选定了对总黄酮进行富集纯化较好的树脂HPD450;采用单因素及正交实验,确定最佳工艺条件:上样量10 mL,以6 mL/min的流速8 BV水、6 BV 80%甲醇溶液洗脱,pH值为6~7。以此方法得到90%以上的赶黄草总黄酮,实验结果良好,总黄酮精制工艺成效显著。用HPLC法精确测定赶黄草中槲皮苷、PGHG和ThA三个指标性黄酮成分,最佳色谱条件为:C18色谱柱,检测波长280 nm,进样量5μL,流动相:乙腈-0.05%磷酸溶液(0~25 min:12%~45%乙腈;25~40 min:45%~70%乙腈)梯度洗脱;精确测定赶黄草全草中3种黄酮成分的含量。采用分光光度法检测,指导优化总黄酮精制工艺,并以HPLC法精确测定三种黄酮代表成分。比较两种方法测定结果相一致,互为补充;故在工业生产时,可以分光光度法指导生产,以HPLC法精确定量测定。     

西兰花叶保健茶萝卜硫素测定方法研究与含量分析

用高效液相色谱法（HPLC）测定西兰花叶保健茶中的萝卜硫素含量,并通过测定发现,西兰花叶保健茶中含萝卜硫素20.848 mg/kg,达到了直接进行90 ℃干燥处理的西兰花中萝卜硫素含量的25%。     

苦荞麦种质资源总黄酮和蛋白质含量的测定与评价

对近几年收集的苦荞麦种质资源进行了总黄酮和蛋白质含量的测定及评价。总黄酮和蛋白质含量测定分别采用三氯化铝比色法和微量凯氏定氮法。结果表明:①总黄酮含量平均2.46%,变异范围1.97%~3.03%;蛋白质含量平均14.3%,变异范围10.9%~20.3%。②不同原产地的材料总黄酮和蛋白质含量存在显著差异,总黄酮含量以来自山西的材料最高,其次依次是湖南、宁夏、贵州、云南材料,最低是四川材料;蛋白质含量的排列次序依次为宁夏、湖南、山西、贵州、云南和四川材料。③相关分析表明总黄酮和蛋白质含量呈极显著正相关,相关系数为0.588。研究认为苦荞麦种质资源的总黄酮和蛋白质含量存在较为丰富的遗传变异并在鉴定评价基础上筛选出一批品质优异的苦荞麦资源。     

心草中总黄酮含量的测定及其提取工艺研究

目的:测定心草中的总黄酮含量并确定其提取条件。方法:采用分光光度法测定、乙醇浸提法提取心草中的总黄酮。结果:浸提的最佳条件是:A3B1C3D2,即用20倍50%乙醇在70℃下进行6h,总黄酮含量为15.675%。平均加样回收率为97.67%。结论:心草中的总黄酮含量较高,此方法简便、快速、重现性好,可作为检测心草中黄酮含量的一种手段。     

阔叶十大功劳叶与花总黄酮提取及含量测定

目的:研究阔叶十大功劳叶与花总黄酮的提取方法和含量测定。方法:比较以索氏提取法、超声波提取法和微波辅助提取法3种方法提取阔叶十大功劳叶与花中总黄酮,用亚硝酸钠-硝酸铝-氢氧化钠比色法测定总黄酮含量。结果:3种提取方法中,微波法提取效率最高,结果重现性好,并测得叶与花中总黄酮含量分别为2.182%和8.155%。结论:阔叶十大功劳总黄酮含量较高,总黄酮在花中的含量明显高于叶。     

广西不同产地番石榴叶总黄酮含量测定

目的对广西不同产地番石榴叶中总黄酮含量进行测定。方法应用紫外分光光度法,以芦丁为对照品,于357nm下测定吸光度,计算番石榴叶中总黄酮的含量。结果在1.7~14.3范围内总黄酮含量与吸光度A值线性关系良好,平均回收率=99.28%,RSD=3.69%,R2=0.9993。结论该方法简便可靠、快速、重现性好,适用于番石榴叶总黄酮含量测定。采收地区不同,番石榴叶中总黄酮的含量也不同。     

四种绿绒蒿属植物中总黄酮含量测定

本文采用比色法测定了4种绿绒蒿属植物中总黄酮的含量,该方法线性关系良好(r2=0.9990),平均回收率为101.56%,精密度和重复性试验RSD分别为2.94%和1.22%,表明本试验的重复性较好。结果显示总黄酮含量以五脉绿绒蒿中最高,全缘和红花绿绒蒿次之,总状绿绒蒿中最低,4种药材总黄酮含量的变化与其用途差异基本吻合,与藏医用药品次习惯较为相符。本实验结果可以为绿绒蒿属药用植物资源的深入研究和开发利用提供一定的理论依据。     

6种晋产野生葛根中葛根素、大豆苷和总黄酮含量比较

采用高效液相色谱法对山西省5地6处野生葛根中主要有效成分葛根素、大豆苷及总黄酮含量进行了分析,并对HPLC法的测定条件(流动相和洗脱程序)进行了优化。结果表明,6种晋产野生葛根中主要有效成分含量差异显著,葛根素的含量为1.46%~4.48%,大豆苷的含量为0.11%~0.62%,总黄酮的含量为11.19%~26.14%。葛根素、总黄酮含量与纬度高低呈正相关。晋南绛县么里镇小北山与夏县泗交镇太宽河自然保护区的野生葛根中葛根素含量低于《中国药典》规定的2.4%,而晋北灵丘县的野生葛根中葛根素含量则高达4.48%。     

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.     

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.     

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。     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

Modulation of allostery of pyruvate kinase by shifting of an ensemble of microstates

Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)₈ barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)₈ structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive E^T and active E^R. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive E^T and active E^R represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.