从喜树叶中提取喜树碱工艺研究

为优化从喜树叶中提取喜树碱工艺条件,以10kg喜树叶为原料得到的提取物中所含喜树碱的质量为指标,采用四因素三水平正交设计法,筛选影响喜树碱提取工艺的因素,探索最优的提取工艺条件。实验证明,合理的提取方法为：pH值为1.9的酸水法浸提3次,上离子交换柱,用pH为3．5的81％的乙醇溶液洗脱,从l0kg喜树叶中得到2.740提取物,其中喜树碱的含量为98．52％。     

胶束介导联合超声—微波辅助法提取喜树叶中喜树碱及羟基喜树碱

为了寻找一种新的方法从喜树叶中提取喜树碱和羟基喜树碱,充分利用喜树资源,以喜树叶粉末作为提取原料,采用超声—微波辅助提取技术提取喜树叶中活性成分喜树碱和羟基喜树碱。采用响应面优化方法设计,分别考察微波时间、料液比、微波功率、表面活性剂的浓度4个因素对总提取率的影响,优化得到最佳提取工艺条件。研究结果表明：当微波时间为10.5 min、料液比为1∶60、微波功率为850 W、表面活性剂浓度为 8.5 g·L^-1时总提取率达到最佳。最佳工艺下总提取率为0.056 4%。     

喜树碱和10-羟基喜树碱受喜树生长发育调控的不同特点

为了揭示喜树碱(camptothecin, CPT)和10-羟基喜树碱(10-hydroxycamptothecin, HCPT)在喜树(Camptotheca acuminata Decaisne)体内代谢的生理调控机制及这两种类似物之间的关系和作用,运用高效液相色谱技术对种子形成、成熟、萌发和幼苗生长过程中喜树碱和10-羟基喜树碱的代谢动态进行了全面的研究.结果表明,喜树碱相对稳定地存在于成熟和幼嫩的组织中;10-羟基喜树碱特异性地积累在乳熟期的种子、种芽的子叶、幼嫩的真叶等幼嫩组织中,随着组织的进一步发育和成熟,其含量快速减少,成熟组织中积累极少,并且这两种生物碱的代谢在时间和数量上都呈现出相互消长的特点,由此推断,这两种生物碱不同程度地受生长发育调控的特点可能与喜树的化学防御策略密切相关,并且,它们之间可以相互转化以充分利用有限的氮素资源.     

喜树碱和10—羟基喜树碱受喜树生长发育调控的不同特点

为了揭示喜树碱（camptothecin,CPT)和10-羟基喜树碱（10-hydroxycamptothecin,HCPT)在喜树（Camptotheca acuminata Decaisne)体内代谢的生理调控机制及这两种类似物之间的关系和作用。运用高效液相色谱技术对种子形成,成熟,萌发和幼苗生长过程中喜树三和10-羟基喜树碱的代谢动态进行了全面的研究。结果表明,喜树碱相对稳定地存在于成熟的幼嫩的组织中;10-羟基喜树碱特异性地积累在乳熟期的种子,种芽的子叶,幼嫩的真叶等幼嫩组织中,随着组织的进一步发育和成熟,其含量快速减少,成熟组织中积累极少,并且这两种生物碱的代谢在时间和数量上都呈现出相互消长的特点,由此推断,这两种生物碱不同程度地受生长发育调控的特点可能与喜树的化学防御策略密切相关。并且,它们之间可以相互转化以充分利用有限的氮素资源。     

羟基喜树碱纳米颗粒超声反溶剂法制备工艺及表征

为提高羟基喜树碱的水溶性及其制剂在体内稳定性,运用超声反溶剂法对羟基喜树碱进行初级颗粒制备。本文根据羟基喜树碱在不同有机溶剂中的溶解度与其在去离子水中的溶解度的不同进行对比,对各项指标进行检测。筛选出制备羟基喜树碱初级颗粒的最佳条件为:HCPT-DMSO浓度为5 mg·mL-1、H2O∶DMSO=1∶1、H2O滴速为4 mL·min-1,超声时间为10 min。对羟基喜树碱初级纳米颗粒进行检测,SEM扫描结果显示其形貌规则,粒径为746 nm,与羟基喜树碱原粉颗粒相比,粒径明显减小并在其水溶液中分布更为均匀。     

碱法提取喜树碱工艺的研究

通过正交试验设计,探讨了以稀NaOH溶液为溶剂从喜树果实中提取喜树碱的工艺条件。确定的最佳工艺条件为:NaOH溶液浓度为0.3%,NaOH溶液用量16ml/g原料·次,提取时间为3~4h,提取温度为室温。     

喜树碱的碱水法提取新工艺

本文根据喜树碱在一定条件下开环和闭环的可逆性,设计了喜树碱的水法提取工艺。     

喜树产10-羟基喜树碱内生真菌的分离鉴定

采用组织块法从喜树(Camptotheca acuminata Decne.)果实中分离筛选得到13株纯化的内生菌株.经过摇瓶发酵培养后,采用TLC法与HPLC法对其菌丝体提取物进行分析,发现有1株菌株能够产生10-羟基喜树碱(10-hydroxycamptothecin,HCPT),其10-羟基喜树碱产量为677 μg/L,并将该菌株命名为XK001.对菌株XK001菌落、菌丝体和孢子的有无进行观察研究,表明菌株XK001暂属于无孢菌群(Mycelia sterlia).     

喜树幼苗中喜树碱和10-羟基喜树碱对热激的响应特点和意义

植物在长期的生态环境适应过程中,产生了包括生物碱在内的大量次生代谢物。本文以我国特有树种——喜树(Camptotheca acuminata Decaisne)为材料,研究其不同器官中喜树碱(camptothecin,CPT)和10-羟基喜树碱(10-hydroxycamptothecin,HCPT)在不同热激温度和时间情况下的含量变化。CPT和HCPT变化呈现出较好的相互消长关系,并且分别在38℃和40℃达到各自的峰值,比以丙二醛和叶绿素为指标的致死温度低了2-4℃：HCPT在热激过程中的变化较CPT活跃;极易受到攻击和伤害的嫩叶中的生物碱含量变化最大。由此推断,CPT和HCPT遵循“幼嫩和生殖器官优先保护”的原则,从而有效地缓解了高温胁迫,并且HCPT和CPT代表了不同的防御策略。     

羟基喜树碱抑制人眼Tenon囊成纤维细胞增殖的实验研究

目的：研究羟基喜树碱（HCPT）对体外培养的人眼Tenon囊成纤维细胞（Human Tenon＇s capsule fibroblasts,HTFs）增殖、移行的影响。方法：取正常供体新鲜的Tenon囊组织,采用组织块培养法,进行成纤维细胞的体外培养,并用光镜、免疫荧光法观察鉴定;MTT法、划痕法检测不同浓度的HCPT（0、0．031、0．062、0．125、0．25、0．5、1、2、4mg／1）对HTFs增殖、移行的影响,并与MMC对比。结果：HTFs体外生长良好,经光镜和免疫荧光法观察鉴定为成纤维细胞;与空白对照组比较,HCPT（0．031-4mg／1）、MMC（0．0031-0．4mg／1）均能有效抑制HTFs的增殖,且呈一定的剂量、时间依赖性,HCPT作用24h、48h、72h的IC50分别为2．24mg／1、O．76mg／1、0．39mg／1,MMC作用24h、48h、72h的IC50分别为0．34mg／1、0．24mg／1、0．07mg／1;与空白对照组比较,HCPT（0．031-4mg／1）、MMC（O．0031-0．4mg／1）均能抑制HTFs迁移,呈剂量依赖性,而与时间无显著相关。结论：HCPT、MMC均能有效抑制HTFs的增殖和移行,其效应MMC约为HCPT的10倍。     

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.     

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.     

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.     

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。     

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.     

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.