枸杞多糖提取工艺的研究

采用热水浸提法从枸杞干果中提取枸杞多糖,经正交实验确定浸提时间、温度、料水比最优值分别为：5h、100℃、1：40;微波预处理超过25min时,多糖得率达15．91％;醇沉时当醇沉时间为4h、乙醇加入量为4倍时有利于枸杞多糖提取。     

怀地黄多糖双酶法提取工艺研究

本文对怀地黄多糖（polysaccharide of Rehmannia glutinosa f.hueichingensis（Chan et Schih）Hsiao,简称为RGP）双酶法提取工艺（Extracting technology by dienzyme,简称DEET）的条件进行了研究和探讨。双酶提取法即在第一次浸提时分别加入纤维素酶和中性蛋白酶两种生物酶进行多糖的辅助提取。本实验选取提取温度、纤维素酶加量、提取液pH、固液比四个因素,以多糖含量作为指标,通过L9（3^4）正交实验确定此工艺的最佳工艺参数。结果表明：RGP双酶法提取的最佳工艺参数为：浸提温度65℃、浸提液pH5．5、纤维素酶加量7．5％、固液比为1：30;浸提液浓缩比为4：1、沉降剂乙醇添加量5倍于浸提液体积;脱蛋白采用浸提过程中中性蛋白酶脱蛋白法与浸提后Sevag脱蛋白法联合应用方法（简称“S＋N”法）,提取得到的RGP含量及得率可分别为60．26％和8．97％。较传统的水浸醇沉提取工艺RGP含量及得率分别提高了1．5倍和1．4倍。     

基于改进熵权法结合TOPSIS模型和BPNN建模优化甘草多糖醇沉工艺

基于改进熵权法结合TOPSIS模型和BPNN建模寻求甘草多糖最佳醇沉工艺。在单因素试验基础上采用正交设计,以浓缩比、乙醇体积分数、醇沉时间为影响因素,甘草总糖、单糖、多糖含量及提取量为评价指标,利用改进熵权法确定评价指标权重,分别采用TOPSIS法和综合评分法处理正交结果,结果显示,TOPSIS法所得数据误差更小,最佳醇沉工艺为浓缩比为2.5 mL/g,乙醇体积分数为70%,醇沉时间为20 h。选取正交设计所得综合评分利用BPNN建模进行仿真寻优,得到最佳醇沉工艺为水提液浓缩至2.0 mL/g,调节乙醇体积分数为67%,醇沉24 h。所得最优工艺验证结果表明,BPNN建模所得综合评分误差更小,工艺更加稳定。该方法优选的最佳醇沉工艺稳定可行,可为甘草多糖进一步开发利用提供客观依据和新思路。     

水提醇沉法提取半枝莲粗多糖中总糖含量的最佳工艺研究

目的：探求传统水提醇沉方法下提取半枝莲粗多糖中总糖最适高效提取方案。方法：通过传统方法以水提取有效成分,以醇除杂精制的方法,改变提取时间、温度、料液比等影响因素,对所获得的半枝莲粗多糖含量进行考查,并通过统计分析方法对工艺进行优化研究。结论：应用水提醇沉法提取半枝莲粗多糖中总糖含量的最佳工艺条件为：浸提温度100℃、料液比1∶3、浸提时间1h。     

响应面分析法优化当归粗多糖提取工艺

选取岷县当归药材为原料,采用水提醇沉法进行多糖提取,以当归粗多糖得率为指标,探讨加水量、回流提取时间、水提液的浓缩比、醇沉后所达含醇比例对当归多糖得率的影响。在单因素分析的基础上,采用响应面分析法(RSM)确定了当归粗多糖最佳提取条件为:加水量837.6 mL/100 g,浓缩后溶液体积为228.12 mL,最终含乙醇浓度为65.80%,回流提取时间2 h,在此条件下预测当归粗多糖得率理论的最佳值为10.44%,实际验证值为10.40%,两者相符,说明RSM法分析的可靠性。     

酶法脱蛋白提取大枣多糖工艺的研究

讨论了从提取环磷酸腺苷后的枣汁中提取枣多糖的最佳工艺条件,包括枣汁浓缩4倍,加无水乙醇调枣汁中乙醇体积分数为60%,醇沉5 h;木瓜蛋白酶脱蛋白效果最佳,木瓜蛋白酶液与枣汁的体积比为0.4∶ 1,温度60℃、pH5.0,酶解90 min,蛋白脱除率可达91.8%;AB-8树脂脱色,脱色率为73.64%,多糖得率为94.4%.红外光谱显示,提取的多糖与常规方法提取的多糖成分相同.     

药用植物三七和金银花多糖提取工艺优化与比较

以野生植物三七、金银花为材料,采用热水浸提、乙醇沉淀、Sevag法除蛋白制备多糖,探讨最佳提取工艺。结果表明,浸提温度和醇沉浓度对金银花多糖提取结果影响较大,其最佳工艺为100℃浸提3 h,氯仿萃取2次,70%乙醇沉淀;影响三七多糖提取的因素顺序为醇沉浓度提取时间提取次数料水比,最佳提取工艺组合为1∶20的料水比提3 h,提取3次,醇沉浓度为80%。根据正交试验结果,金银花粗多糖最高提取率为3.05%,三七粗多糖最高提取率为15.96%,云南文山三七与河南巩义产金银花相比含有较多的多糖。     

乙醇浸提法提取大枣芦丁及其抗氧化性的研究

以大枣为原料,采用乙醇浸提法提取芦丁,以芦丁得率为评价指标,通过正交试验优化影响大枣芦丁得率的若干因素:液料比、乙醇浓度、浸提时间、浸提温度,确定其最佳工艺条件为液料比20∶1(mL∶g)、乙醇浓度60%、浸提时间3.0 h、浸提温度70℃,此条件下大枣芦丁得率为2.16%;大枣芦丁粗提物中芦丁含量为8.57%。对芦丁进行体外抗氧化能力测定结果表明,大枣芦丁具有一定的清除DPPH自由基的能力,5μg/mL的大枣芦丁对DPPH自由基的清除率可达到58.80%,25μg/mL的芦丁对OH自由基的清除率达49.80%,本研究对芦丁资源的进一步开发利用提供参考。     

裂蹄木层孔菌多糖的提取工艺及抗氧化活性研究

以多糖提取率为检测指标,采用水提醇沉法提取裂蹄木层孔菌多糖。正交实验考察提取温度、提取时间和料液比对多糖提取率的影响。结果显示,提取温度和料液比对多糖提取率有显著性影响,提取时间对多糖提取率无显著性影响。最佳提取工艺为提取温度80℃、提取时间2 h、料液比1∶40(g/m L)。在此条件下,多糖平均提取率为3.20%。选用终体积分数70%的乙醇沉淀多糖12 h时,多糖得率最高。体外抗氧化活性实验结果显示,裂蹄木层孔菌多糖的总抗氧化能力、清除羟自由基和超氧阴离子自由基的能力在实验范围内随着多糖质量浓度的增加而增强。裂蹄木层孔菌多糖是一种具有抗氧化功能的药用真菌多糖。     

牛樟芝固态发酵菌丝体三萜及多糖提取工艺优化研究

为研究牛樟芝固态发酵菌丝体中三萜和多糖的最佳提取工艺，选取浸提时间、料液比和提取温度3个因素，分别设置3个水平，以三萜和多糖得率为指标，并采用正交试验法进行分析。结果表明，三萜的最佳提取工艺条件为：浸提时间3 h、料液比1∶30 (g·mL-1)、温度70 ℃，在此条件下，得率为3.43%；多糖的最佳提取工艺为：浸提时间2 h、料液比1∶20 (g·mL-1)、温度95 ℃，在此条件下得率为4.71%。研究结果为牛樟芝固态发酵菌丝体中三萜和多糖的提取工艺提供了参考。     

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.