江西虫草发酵液脱色及其多糖提取分离的优化工艺*

通过单因素和正交试验法,优化了江西虫草发酵液脱色的工艺条件。即在提取多糖前,调节发酵液pH值至5,活性炭用量为3g／100mL,在25℃恒温条件下吸附5min后,发酵液脱色率可达到89．6％,发酵液多糖的耗损率仅为10．7％。在此基础上,采用正交试验法,对发酵液多糖提取工艺进行了优化。利用优化后的工艺,即经脱色和去蛋白后发酵液滤液浓缩至其总体积的1／7,加入乙醇,终浓度为80％,醇析16h,发酵液多糖的得率可达到0．38g／L。     

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。     

红曲多糖液态发酵工艺条件的优化

实验研究红曲多糖的液态发酵条件,得出优化后红曲菌ZKOA发酵工艺条件：蔗糖40g/L,酵母粉4．5g／L,KH2PO4·3H2O3．5∥L．MgSO40．4g／L,植物油2mL／L,接种量8％,种龄30h,发酵液起始pH5．0,发酵时间90h,在此条件下,摇瓶和中试发酵罐中的粗多糖质量浓度分别为7．6g／L和7．34g/L。     

羊肚菌胞外多糖提取工艺研究

[目的]探究从羊肚菌发酵液中提取胞外多糖的最佳工艺。[方法]实验原料为羊肚菌发酵液,采用单因素实验的方法探究在不同醇沉浓度、醇沉温度、醇沉时间、醇沉p H的条件下,运用正交实验分析从羊肚菌发酵液中提取多糖的最佳工艺条件;根据实验结果,提取7 d中羊肚菌胞外多糖,分别绘制多糖变化曲线和菌丝体生物量曲线。[结果]通过对羊肚菌胞外多糖提取的研究得到最佳工艺条件为:醇沉浓度95%,醇沉温度-25℃,醇沉时间24 h,醇沉p H 7。[结论]利用优化后的实验条件得出,羊肚菌胞外多糖含量最高为0. 874 g/L,在一定程度上为羊肚菌胞外多糖的研究提供了依据,具有十分重要的意义。     

粗柄羊肚菌菌丝体多糖及胞外多糖的提取工艺

为了研究粗柄羊肚菌菌丝体多糖及胞外多糖的最佳提取工艺条件,采用超声波提取菌丝体多糖、菌丝体发酵液浓缩提取胞外多糖的方法。通过单因素试验和L9(34)正交试验设计,探讨二者的最佳提取工艺条件。研究结果表明菌丝体多糖的最佳提取工艺条件:料液比1∶20(g∶m L),超声波处理温度70℃,超声时间20 min,超声提取次数2次;胞外多糖的最佳提取工艺条件:浓缩倍数1∶5,浓缩温度50℃,醇沉浓度95%,p H为6。该项工艺研究得到菌丝体粗多糖平均含量56.761 2 mg/g,胞外多糖平均含量1.275 4 mg/m L,多糖产量稳定,且此试验方法稳定可行。     

响应面法优化微波辅助提取发酵虫草菌丝体多糖工艺

为优化发酵虫草菌粉多糖的微波辅助提取工艺,在单因素实验基础上,以液固比、微波功率以及提取时间为自变量,多糖提取率为响应值,采用中心组合设计的方法,研究各自变量及其交互作用对多糖提取率的影响。利用SAS软件和响应面分析相结合的方法对发酵虫草菌粉多糖的微波辅助提取工艺进行优化,确定了微波辅助提取多糖的最佳条件：液固比值12．2,微波功率650．5W,提取时间11．8min,在此条件下,多糖提取率达到6．41％。采用此法提取的虫草菌丝体多糖,当质量浓度为1mg／mL时,对二苯代苦味肼基自由基（DPPH）清除率达到76％。     

响应面法优化超声提取绿茶茶多酚工艺

利用响应面法对超声提取绿茶荼多酚的工艺条件进行优化,在单因素试验的基础上,根据中心组合设计原理采用三因素三水平的响应面分析法,依据回归分析确定最优提取工艺条件。结果表明,其最佳工艺条件为：液料比为40．2mL／g,超声功率为476W,提取时间为15．1min,采用该工艺条件,茶多酚的提取得率达到10．312％,通过响应面法得到一个能较好预测试验结果的模型方程。     

丙酮提取金顶侧耳发酵液多糖的优化设计

以液体深层发酵法培养金顶侧耳,发酵液以丙酮为提取剂在不同的浓度﹑时间﹑温度条件下提取多糖,利用正交设计试验分析,得到了一种优化方案。试验结果表明:发酵液多糖提取最优方案是提取温度为70℃、丙酮浓度为75%、提取时间为1.5h。     

海南红树林淡紫拟青霉胞外多糖提取条件的优化

为了探讨影响红树林淡紫拟青霉胞外多糖提取的因素,确定最佳提取方案,设置不同的发酵液浓缩倍数、三氯乙酸用量等因素,设计单因素实验测定多糖提取最佳条件。然后设计正交试验,检测多糖在不同条件下的提取率,以获得最佳提取工艺。结果发现,发酵液浓缩3~5倍时多糖提取率最高,10%的三氯乙酸对蛋白质脱除效果最好;正交试验表明影响多糖提取的因素依次为乙醇用量、沉淀时间和温度,最优方案为3倍95%乙醇、4 ℃沉淀24 h。该条件下,多糖提取率可达57.835%±1.206%。研究结果为红树林淡紫拟青霉胞外多糖的提取研究提供了参考。     

山茱萸多糖大孔树脂脱色技术的优化

以脱色率、多糖保留率和细胞抑制率3个指标,从D301、D303、D315、D900树脂筛选出脱色效果较好的树脂;采用MTT法检测,脱色后的山茱萸粗多糖抗HL-60细胞活性提高;对D303树脂,通过单因素和正交试验对其进行优化,确定最优工艺条件是时间7 h、温度50℃、样品浓度15 mg/m L,脱色率和多糖保留率分别为79.71%、81.12%。大孔树脂脱色工艺的研究,为山茱萸药物的研发提供了一定实验基础。     

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.     

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.     

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.