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51.
龚玉莲 《现代生物医学进展》2005,5(2):29-32
综述了何首乌的快速繁殖、愈伤组织的诱导和培养、毛状根的诱导和培养以及活性成分的产生,并展望了何首乌生物技术的前景。 相似文献
52.
扁蓄总黄酮含量的测定 总被引:8,自引:0,他引:8
以35%乙醇为提取溶剂,聚酰胺吸附提纯,芦丁为标准品,用分光光度法于510nm处测定了扁蓄各部位的总黄酮含量。结果表明:扁蓄全草总黄酮含量为4.349%,根为7.115%,茎为5.454%,叶为3.544%。 相似文献
53.
气象因子和矿质元素对虎杖根茎白藜芦醇含量的影响 总被引:8,自引:0,他引:8
对全年各月虎杖材料中白藜芦醇含量,及其Ca、Cu、Fe、K、Mg、Na、Zn 8种矿质元素积累进行检测,结合气象因子动态变化,采用主成分分析法,研究了不同季节虎杖白藜芦醇含量动态变化与其矿质元素、气象因子动态变化的关系.结果表明,Cu与Fe,Mg与K、Zn,Ca与月日照时数,K与Zn相关系数分别为0.812、0.871、0.793、0.602、0.729,呈极显著正相关;Cu、Mn与月平均气温,Fe与K相关系数分别为-0.738、-0.712、-0.766,呈极显著负相关;Cu与白藜芦醇含量呈显著负相关.找出了影响虎杖白藜芦醇含量动态变化的5个主成分,其中“酶促反应促进性矿质营养因子”,“高温、强照射气象因子”的贡献率分别为35.539%、33.358%,合计为68.897%,二者对不同季节虎杖白藜芦醇的变异贡献率最大.同时进行白藜芦醇含量的动态变化与主成分的多元相关、回归分析,建立了回归方程。 相似文献
54.
储藏方式和时间对三峡水库消落区一年生植物种子萌发的影响 总被引:1,自引:0,他引:1
为了明确不同储藏方式和储藏时间对三峡水库消落区4种1年生植物稗(Echinochloa crusgalli)、苍耳(Xanthium sibiricum)、合萌(Aeschynomene indica)和水蓼(Polygonum hydropiper)种子萌发能力的影响,筛选出有利于其萌发的最佳储藏方式及时间,采取5种储藏方式(室温、冷藏、冷冻、干沙、湿沙)、8个储藏时间段(30、60、90、120、150、180、210、240d)对种子进行储藏实验。在光照培养箱昼25℃/夜20℃和周期性光照(昼12h/夜12h,光强100μmol·m-·2s-1)条件下进行种子萌发,每次萌发持续时间为30d。结果显示:(1)稗、苍耳和水蓼的种子在湿沙储藏条件下萌发起始时间缩短,种子萌发率、萌发指数高于其它储藏方式;湿沙储藏条件下,稗的种子储藏90-180d萌发率达到80%以上,苍耳的种子储藏180d萌发率达(64±2)%,水蓼的种子储藏30-240d萌发率均超过90%。(2)冷冻储藏能有效地解除合萌种子休眠,显著提高其种子萌发率和发芽指数;冷冻储藏90-180d合萌的种子萌发率均超过80%,之间没有显著差异。(3)果皮是限制苍耳种子萌发的主要因素之一,而去除果皮对合萌种子萌发没有显著影响。研究结果建议:采用种子来进行消落区植被恢复和重建时,稗、苍耳和水蓼的最佳储藏方式是湿沙储藏,合萌的最佳储藏方式是冷冻储藏。结合三峡水库水位调度原则,在适宜的储藏方式下,本实验中储藏120-180d的种子能够应用于消落区实地播种中。 相似文献
55.
56.
Marc J.M. Hagendoorn Threes A.M. Geelen Teris A. van Beek Diaan C.L. Jamar Frans A.A. Tetteroo Linus H.W. van der Plas 《Physiologia plantarum》1994,92(4):595-600
Shoots of Polygonum hydropiper L. (waterpepper), especially in the leaves and flower-heads, contain significant amounts of the sesquiterpenoid polygodial, a compound with a potential use as a natural pesticide. The polygodial content of the tepals is particularly high: up to 8.5% of the dry weight. Roots and seeds do not contain detectable amounts of polygodial. Polygodial containing organs e.g. leaves and tepals, were found to contain cavities. Fourier transform infra-red (FTIR) microspectroscopy demonstrated that polygodial or its congeners are found in these cavities but not in other tissues or cells. Comparable cavities containing polygodial-like compounds were absent in the closely related species Polygonum persicaria L.
Callus cultures and cell suspensions as well as root- and shoot cultures were initiated from mature P. hydropiper plants. Polygodial could be detected only in shoot cultures. Our results indicate that functioning plastids may be essential for polygodial production and cavities for its accumulation. 相似文献
Callus cultures and cell suspensions as well as root- and shoot cultures were initiated from mature P. hydropiper plants. Polygodial could be detected only in shoot cultures. Our results indicate that functioning plastids may be essential for polygodial production and cavities for its accumulation. 相似文献
57.
58.
Hyeji Shin Yeeun Park Young Ho Jeon Xi-Tao Yan 《Bioscience, biotechnology, and biochemistry》2018,82(1):15-21
Our primary focus in this research was to identify and characterize its bioactive compounds for potential therapeutic use. Twenty-seven metabolites of Polygonum orientale were identified using LC-QTOF tandem mass spectrometry. Interestingly, P. orientale extracts included several highly oxygenated flavonoids were isolated from P. orientale by column chromatography. 13C NMR data of highly oxygenated flavonoids (1–7) are reported here for the first time. In addition, nitric oxide, 1,1-diphenyl-2-picrylhydrazyl, and water-soluble tetrazolium salt assays were carried out on the isolated compounds to investigate their anti-inflammatory, anti-oxidant, and neuroprotective activities, respectively. Compounds 1, 2, 3, 5, 7, and 8 significantly attenuated lipopolysaccharide-stimulated NO production in BV2 cells without affecting cell viability. Compounds 9–12 exhibited significant antioxidant activity, while compounds 8, 9, and 12 exhibited protective effects against glutamate-induced neurotoxicity in HT22 cells. Our results indicate that P. orientale is a promising source of natural agents for the potential treatment of inflammation and neurodegenerative diseases. 相似文献
59.
60.
Takehiro Masuzawa 《Journal of plant research》1987,100(1):103-108
Measurements of photosynthetic activity ofPolygonum weyrichii var.alpinum were carried out in a field at the timberline of Mt. Fuji and in the laboratory in summers of 1982 and 1983. In order to
measure photosynthesis at remote alpine locations, measurement systems were divided into several units small enough for carrying
by one person. In addition, special care was taken in collecting and transporting plant materials for photosynthetic measurement
in the laboratory. Good agreement was found for the light-photosynthesis curves between the field and laboratory measurements. 相似文献