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1.
菜青虫不同虫态及虫龄的多酚氧化酶性质比较   总被引:20,自引:2,他引:18  
初步比较了菜青虫Pieris rapae (L.)不同虫态及虫龄的多酚氧化酶(polyphenol oxidase)的性质。结果表明,不同虫态及虫龄的多酚氧化酶活力有很大的不同,其中以5龄幼虫酶活力最高,蛹酶活力最低。酶活力大小依次为: 5龄幼虫> 预蛹>4龄幼虫>3龄幼虫>蛹。以邻苯二酚为底物,研究了pH对多酚氧化酶活力的影响,结果表明酶催化底物氧化均有一个最适pH区域,不同虫态及虫龄的多酚氧化酶最适pH基本相同,其值为7.0±0.2 。不同虫态及虫龄的多酚氧化酶催化底物氧化的最适温度有很大的差异。3龄、4龄、5龄幼虫、预蛹和蛹的多酚氧化酶活力的最适温度分别为36.0±0.5℃、38.5±1.0℃、43.0±1.0℃、45.5±1.0℃和50.0±1.5℃,说明蛹期的多酚氧化酶活力的最适温度较高。进一步比较催化底物氧化反应的活化能,测得3龄、4龄、5龄幼虫、预蛹和蛹的多酚氧化酶活化能分别为:4 3.10±0.28、36.50±0.27、25.79±0.32、30.10±0.21和58.88±0.39 kJ/mol 。通过测定不同虫态及虫龄的多酚氧化酶催化邻苯二酚和L-多巴氧化反应的动力学特征参数,比较了不同虫期的酶对底物的亲和力。  相似文献   

2.
采用GA3诱导菠萝多酚氧化酶活性升高的机理   总被引:1,自引:0,他引:1  
在多酚氧化酶(PPO)提取过程中,直接加入GA3溶液,不能使PPO活性增加。采后GA3诱导菠萝PPO活性升高的同时,显著提高了酸性酸酯酶的活性,这是果实组织的Pi浓度明显升高的主要原因。随着果实的后熟,磷脂磷D活性不断下降,GA3处理显著延缓了该酶的下降速度。虽然采用ABA处理使果实PPO活性有小幅度增加,但ABA处理能使GA3对PPO活性的诱导明显加强。  相似文献   

3.
金针菇的多酚氧化酶(PPO)、过氧化物酶(POD)和过氧化氢酶(CAT)活性在全株中呈现区域化分布。菌盖的酶活性最低,菌柄上部酶活性稍高,菌柄中部较高,菌柄下部活必同。用硫脲、亚硫酸盐、CaCl2、高CO2、低O2、低温等方法处理金针菇,对以上三种酶的活性均有抑制作用。高O2、H2O2和温度的提高无益一种酶生。高N2(减压后充N2)不能抑制三种酶活性。  相似文献   

4.
对从中国红豆杉的茎来源的愈伤组织经筛选而得的sinenxans高产细胞系Ts19的过氧化物酶(POD)、酯酶(EST)、细胞色素氧化酶(COD)、淀粉酶(AML)、多酚氧化酶(PPO)及超氧化物歧化酶(SOD)的同工酶,可溶性蛋白的含量及电泳谱带、超氧化物歧化酶、多酚氧化酶和苯丙氨酸解氨酶(PAL)的活性作了比较研究。并与培养过程中sinenxans含量的动态变化相比较,探索了这几种同工酶的酶谱和  相似文献   

5.
采后GA_3诱导菠萝多酚氧化酶活性升高的机理   总被引:2,自引:0,他引:2  
在多酚氧化酶(PPO)提取过程中,直接加入GA3溶液,不能使PPO活性增加。采后GA3诱导菠萝(Ananascomosus(L.)Mer.)PPO活性升高的同时,显著提高了酸性磷酸酯酶的活性,这是果实组织的Pi浓度明显升高的主要原因。随着果实的后熟,磷脂酶D活性不断下降,GA3处理显著延缓了该酶的下降速度。虽然采后ABA处理使果实PPO活性有小幅度增加,但ABA处理能使GA3对PPO活性的诱导明显加强。  相似文献   

6.
对碧冬茄和烟草的野生型以及RBP2转化植transformant)叶片中过氧化物酶(POD)的特笥做了分析,结果表明FBP2在花中的可以调节叶片特异POD的表达,并影响其活性。此外,FBP2在花中的表达还影响叶片内源植物生长物质的水平以及多酚氧化酶(PPO)和过氧化氢酶(CAT)的活性。结果表明:花同源异型基因不仅调控花器官的发育,而且参与营养器官代谢的调节,使之适应于生殖器官的生长发育。  相似文献   

7.
二氧化硫污染对植物体酶活性的影响   总被引:4,自引:0,他引:4  
李维典  颜培辉 《生态科学》1996,15(1):117-119
通过用6种浓度的SO2气体对6种植物进行熏气处理,然后测定植物叶片内的过氧化物酶,抗坏血酸氧化酶及多酚氧化酶的活性,为环境监测提供理论依据。通过试验,发现SO2气体对植物叶内不同酶的活性的影响有别。6种植物受不同浓度的SO2污染,叶内的过氧化物酶活性随SO2浓度增加而增加,促进叶片的衰老;而对其他的2种酶,则6种植物表现不同  相似文献   

8.
在生物学观察测定基础上,引入生化测定方法探讨不同光照条件下卡洲满江红3001 、小叶满江红4018 、杂交萍9046 和回交萍MH31 四个红萍品系体内多酚氧化酶(PPO) 活性变化趋势。结果表明,光照影响各满江红品系的生长速率与抗霉腐病能力,随着光照强度减弱,各品系的生长速率和抗霉腐病能力都下降。在低光下,供试的满江红品系生物量与体内PPO 活性的相关性显著(r= 0 .9560) 。低光下满江红各品系生长速率、抗霉腐病能力和体内PPO 活性的从高到低依次为卡洲满江红3001 、杂交萍9046 、小叶满江红4018 和回交萍MH31 。从生理、生化角度讨论了满江红耐荫性与体内多酚氧化酶活性的关系。  相似文献   

9.
云南松树干接种纵坑切梢小蠹伴生真菌后,其韧皮部反应区的苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)和超氧化物歧化酶(SOD)均显著提高,丙二醛(MDA)含量吸显增加。在水分状况差的条件下,PAL、PPO和SOD活性变化幅度大于水分状况好的,MDA含量上则相反。这与水分善较好的地点真菌侵染力测度试得到的反应区长度和真菌生长长度较长于水分善较差的地点结果一致。  相似文献   

10.
对从中国红豆杉的茎来源的愈伤组织经筛选而得的sinenxans高产细胞系Ts19的过氧化物酶(POD)、酯酶(EST)、细胞色素氧化酶(COD)、淀粉酶(AML)、多酚氧化酶(PPO)及超氧化物歧化酶(SOD)的同工酶,可溶性蛋白的含量及电泳谱带、超氧化物歧化酶、多酚氧化酶和苯丙氨酸解氨酶(PAL)的活性作了比较研究。并与培养过程中sinenxans含量的动态变化相比较,探索了这几种同工酶的酶谱和两种酶活性与sinenxans的生物合成的关系。旨在为建立紫杉醇生物合成的中间代谢模型奠定基础。  相似文献   

11.
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.  相似文献   

12.
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 Pfr.  相似文献   

13.
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.  相似文献   

14.
15.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
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.  相似文献   

16.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
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。  相似文献   

17.
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.  相似文献   

18.
19.
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.  相似文献   

20.
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.  相似文献   

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