沙冬青种子总黄酮测定方法及纯化工艺研究

旨在建立沙冬青种子总黄酮测定方法及沙冬青种子总黄酮纯化工艺。选用常用4种黄酮显色方法,通过紫外波长扫描分别确定槲皮素为对照品及沙冬青种子总黄酮的最佳吸收波长,建立标准曲线,并对各测定方法进行方法学验证,利用新建立的条件方法对沙冬青种子总黄酮进行含量测定;实验选择AB-8、D101、S-8型大孔树脂通过静态吸附及解析试验,筛选出AB-8型大孔树脂进行动态试验,建立大孔树脂纯化工艺条件,进一步通过乙酸乙酯进行萃取,提高其总黄酮纯度。结果显示,以槲皮素为对照品,采用Al Cl3-CH4O显色法,在检测波长为335 nm条件下可对沙冬青种子总黄酮含量进行有效测定;AB-8型大孔树脂在上样液浓度为6 mg/m L、上样液p H5.5、上样液体积5 BV、上样液流速3.5 BV/h条件下吸附,以70%乙醇、洗脱液流速1.5 BV/h、洗脱液体积6 BV条件下洗脱,沙冬青种子总黄酮含量由纯化前5.69%提高到41.07%;用AB-8树脂纯化后的总黄酮配置成一定浓度溶液后用乙酸乙酯萃取,总黄酮含量达到76.15%。     

甜叶菊渣中总黄酮的纯化工艺研究

以甜叶菊渣为原料,采用大孔树脂吸附和溶剂萃取法相结合的方法,得到90％以上纯度的总黄酮.通过对大孔树脂及溶剂萃取法的各影响因素进行研究,确定纯化甜叶菊渣中总黄酮的最佳工艺条件:AB-8型大孔树脂吸附流速为2 mL/min、上样液质量浓度1.5 mg/mL、上样液pH值为3.5、上样量4 BV,解吸液为50％乙醇溶液、解吸量5 BV、解吸流速为1.5 mL/min.优化后的甜叶菊总黄酮平均纯度为50.11％.后经乙酸乙酯在常温条件下萃取5次,得到甜叶菊渣中总黄酮纯度为91.8％.结果表明:通过AB-8型大孔吸附树脂和乙酸乙酯萃取相结合的方法,可以很好地纯化甜叶菊总黄酮.     

拟草果总黄酮制备纯化及抗炎活性研究

该文在前期研究的基础上,以拟草果的甲醇粗提液为原料,研究了拟草果总黄酮成分的纯化方法以及考察拟草果总黄酮的抗炎活性。结果表明:采用静态吸附-洗脱试验筛选HP-20为纯化拟草果总黄酮的最佳大孔吸附树脂; 以吸附率、解吸率等参数为指标,考察上样液和洗脱液的质量浓度、体积、流速等因素对纯化工艺的影响,确定最佳工艺条件:上样液质量浓度为0.5 mg·mL^-1、上样体积流量为4 mL·min^-1、上样体积为15 BV、洗脱剂乙醇浓度为70%、洗脱流速为2 mL·min^-1、洗脱剂用量为10 BV,在此条件下纯化的总黄酮保留率为65.48%; 通过检测获得的拟草果总黄酮对脂多糖刺激的小胶质BV2细胞中白介素(IL)-6水平的影响发现,其可显著下调炎症因子IL-6的表达,具有一定的抗炎活性。     

陕北红枣中多糖的酶加水法提取工艺研究

以多糖含量和得率为指标,采用正交试验法对陕北红枣中多糖的提取与分离工艺进行优选。酶加水提取的最佳工艺为：①温度70℃、酶添加量3．0％、时间2h;②温度70℃、酶添加量2．0％、时间4h。分离的最佳工艺为：分级沉淀多糖时采用浓缩液：无水乙醇（v／v）1：3效果最好;当采用活性炭脱色时,活性炭用量为7g／L时,既达到了脱色的目的,多糖的损失率又较小。     

HZ-841吸附树脂精制银杏叶总黄酮

本文研究了用HZ-841吸附树脂精制银杏叶总黄酮的工艺。用10 BV 70％的乙醇分三次提取脱脂银杏叶粉中的银杏叶总黄酮,其收得率为4．8％,纯度为21．7％;用30BV纯净水、微波解冻提取30min,银杏叶总黄酮的收得率及纯度分别是2．63％和13．4％。HZ-841树脂对银杏叶总黄酮的动态吸附容量在pH=7．0时为0．265g／mL,树脂,动态吸附平衡时间为10min。酸度对HZ-841树脂吸附银杏叶总黄酮有显著影响,当pH=5．0时,其静态吸附量可达到0．322g／mL。吸附了银杏叶总黄酮的HZ-841树脂可用乙醇洗脱,当洗脱液pH=9．0、乙醇浓度为90％、洗脱流速3BV／h时,5BV洗脱液的收得率为1．8％。用无水乙醇洗脱的银杏叶总黄酮经过真空浓缩、干燥,获得的浅黄色粉末中银杏叶总黄酮含量为37．3％,产品收得率为2．41％。     

大孔吸附树脂AB-8和十八烷基硅胶色谱分离纯化蛹虫草发酵液中虫草素工艺研究

主要研究了从蛹虫草发酵液中提取虫草素的工艺,确定了大孔吸附树脂AB-8及十八烷基键合硅胶反相层析柱对蛹虫草发酵液中虫草素的分离条件;吸附最佳工艺条件为上样液p H6,上样浓度0.4mg/m L,上样量5BV,吸附流速1.0BV/h;解吸最佳工艺条件包括解吸液20%乙醇,解吸体积15BV,解吸流速4BV/h。得到的解吸液进一步以十八烷基键合硅胶分离,条件为上样液p H6,梯度洗脱,流动相为p H6的水和p H6的乙醇。洗脱液通过结晶和重结晶得到精制虫草素。三步得到的虫草素纯度分别达到40%、90%和99%以上。     

葛根总黄酮提取工艺的研究

目的:筛选提取葛根总黄酮的最佳工艺条件。方法:采用单因素和正交试验对提取葛根总黄酮的工艺条件进行优化;利用紫外可见分光光度计测量葛根总黄酮的含量;利用高效液相色谱仪测量葛根素的含量;分别以葛根素和葛根总黄酮的含量为指标进行最优工艺的评价。结果:最佳工艺条件是以9倍量的30%乙醇提取3次,每次1h。结论:该提取工艺简单,成本低,适合于生产应用。     

大孔树脂分离纯化辣椒叶总黄酮的工艺研究

目的:筛选适合分离纯化辣椒叶总黄酮的一种大孔树脂,同时用响应面法进行优化得到最佳纯化工艺。方法:采用热回流法提取辣椒叶总黄酮,以吸附率和解吸率为考察指标,考察6种不同型号的大孔树脂(HPD100、HPD450、HPD600、HPD826、D101、AB-8)对辣椒叶总黄酮的吸附能力与解吸能力,确定最佳树脂。通过动态吸附解吸实验考察此树脂对辣椒叶总黄酮的最佳分离纯化工艺。结果:通过对辣椒叶总黄酮吸附分离性能的分析显示HPD600为最佳树脂,最优工艺为:上样浓度为10 mg/mL,上样量为10 mL,洗脱体积为4 BV,洗脱液流速为4 mL/min,洗脱液pH为7,依次用水、10%、30%乙醇冲洗树脂柱,50%乙醇为洗脱液。纯化后的黄酮纯度435.4 mg/g。结论:该方法简便,操作简单,对辣椒叶总黄酮的纯化效果较好。     

藜蒿总黄酮提取工艺研究

本文采用单因素实验和正交实验设计,对藜蒿总黄酮的乙醇提取工艺和水提工艺分别进行了系统考察。结果发现,以总黄酮得率作为考察指标,藜蒿总黄酮的乙醇最佳提取工艺条件为：70℃用20倍量45％乙醇提取2次,每次1．75h。藜蒿总黄酮的最佳水提工艺条件为：95℃用25倍量的水提取2次,每次1．5h。醇提法0．412％的得率比水提法得率0．372％略高。     

绿豆皮中黄酮类化合物提取工艺

研究了绿豆总黄酮的提取工艺。通过对固液比、乙醇体积分数、提取温度与提取时间的单因素实验确定水平点,设计4因素3水平实验,选用L9（3^4）正交表,优选绿豆总黄酮的最佳提取工艺为固液比1：50,φ（乙醇）为40％,提取温度70℃,提取时间120min。在此基础上得到绿豆皮中总黄酮的提取量为27．57mg／g,且5次平行的相对标准偏差为0．75％,总黄酮的平均回收率达97．5％。     

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.     

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.     

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.     

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.