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An anthocyanin-producing suspension culture of Daucus carota (L.) cv. Flakkese was used as model system to study secondary metabolite production in cell culture at the individual cell level. An approach was set up in which growth and production of anthocyanins were investigated using a combination of biochemical analysis, image (colour) analysis and in vivo imaging. This novel approach was used to segment the culture in different subpopulations and dissect the productive process in the cell culture grown under two different conditions, known to differ mainly for oxygen supply and mixing intensity (volume of 50 ml or 20 ml in 250 ml flasks). The 20 ml batch cultures gave a higher content and yield of anthocyanins, which depended on a complex balance between events that positively or negatively affected anthocyanin production. A model is proposed in which the different ability of cells to respond to environmental stimuli and stress depends on the different amount of anthocyanins accumulated within cells. 相似文献
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Anthocyanin Accumulation Mediated by Blue Light and Cytokinin in Arabidopsis Seedlings 总被引:1,自引:0,他引:1
Da-Qing Chen Zhi-Yang Li Rui-Chi Pan Xiao-Jing Wang 《植物学报(英文版)》2006,48(4):420-425
It has been reported that pigmentation In plants Is stimulated by light and cytoklnln (CTK); however, the signaling pathways and the relationship between light and CTK Involved In the regulation of anthocyanln accumulation remain to be elucidated. We Investigated (i) the role of blue light (BL) and CTK In anthocyanln accumulation ; and (ii) the relationship between BL and CTK In wild type (WT) and by4 mutants of Arabidopsis thaiiana. Two-d-old seedlings grown on medium with or without klnetln (KT) or zeatln (ZT) In darkness were Irradiated using BL at different fluence rates for 3 d before the anthocyanln content was determined using a spectrophotometrlc method. Anthocyanln accumulation was strongly Induced by BL In WT seedlings but not In hy4 seedlings, which demonstrated that CRY1 Is the main photoreceptor for BL. Both KT and ZT enhanced the response of the WT seedlings to BL In a dose-dependent manner, whereas they were not sufficient to promote anthocyanln eccumulatlon In darkness. In addition, data from experiments using the hy4 mutant showed that the CTK effect of BL was also CRYl-dependent. The results from experiments with three different treatment programs showed that the relationship between BL and KT In anthocyanln accumulation of Arabidopsis seedlings seems neither muItlpllcatlve nor additive coactlon, but rather Interaction. BL Is necessary for anthocyanln accumulation, and KT might be Involved In the BL signaling pathway. 相似文献
45.
环境因子调控植物花青素苷合成及呈色的机理 总被引:1,自引:0,他引:1
花青素苷(anthocyanin)是决定被子植物花、果实和种皮等颜色的重要色素之一。花青素苷的合成与积累过程往往与植物发育过程密切相关,由内外因子共同控制。环境因子通过诱导植物体内花青素苷合成途径相关基因的表达来调控花青素苷的呈色反应。该文追踪了国内外相关研究,认为光是影响花青素苷呈色的主要环境因子之一,光质和光强均能在一定程度上影响花青素苷的合成,其中光质起着更为关键的作用;低温能诱导花青素苷的积累,高温则会加速花青素苷的降解;不同的糖类物质均能影响花青素苷的合成,大部分结构基因和调节基因的表达均受糖调控。关于花发育与花青素苷呈色的关系、观赏植物花色对环境因子的响应以及花青素苷抵御逆境的机理尚待深入研究。因此,综合考察花发育与植物花青素苷合成及其呈色之间的关系,特别是光周期对花发育的影响导致花青素苷合成及呈色的机理是花色研究的一个重要课题。利用环境因子调控花色将会极大地提高花卉的观赏价值。 相似文献
46.
菊花不同花色品种中花青素苷代谢分析 总被引:2,自引:0,他引:2
应用高效液相色谱和多级质谱联用技术(HPLC-ESI-MSn),分析菊花(Chrysanthemum×morifolium)白色、粉色、红色、紫色、红紫色和墨色6个色系共计82个品种中花青素苷合成过程的中间产物和最终产物,发现从白色、粉色、红色、紫色、红紫色到墨色花青素苷含量快速增加,分别为4.68、111.60、366.89、543.56、1220.36和2674.95μg·g-1,不同色系间花青素苷的含量差异显著(P〈0.01),花青素苷含量越高花色越深;墨色菊花品种中总类黄酮含量显著高于其它花色品种(P〈0.01),其它不同色系间总类黄酮含量差异不显著(P〉0.05);随着菊花花色变深,从柚皮素分支到圣草酚的代谢流,以及从圣草酚分支到矢车菊素苷的代谢流比例增加。花青素苷成分分析发现:菊花中只含有矢车菊素苷类化合物。根据花青素苷代谢成分分析结果绘制了菊花中花青素苷代谢路径图,即在菊花类黄酮代谢途径中只存在矢车菊素苷代谢分支途径;菊花不同色系在柚皮素和圣草酚2个关键代谢分支点上向不同方向代谢流的分配比例不同,造成花青素苷产物含量不同,导致不同花色。以上研究结果为菊花花色改良的分子育种提供了理论依据。 相似文献
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Structure of anthocyanin from the blue petals of Phacelia campanularia and its blue flower color development 总被引:1,自引:0,他引:1
The dicaffeoyl anthocyanin, phacelianin, was isolated from blue petals of Phacelia campanularia. Its structure was determined to be 3-O-(6-O-(4'-O-(6-O-(4'-O-beta-d-glucopyranosyl-(E)-caffeoyl)-beta-d-glucopyranosyl)-(E)-caffeoyl)-beta-d-glucopyranosyl)-5-O-(6-O-malonyl-beta-d-glucopyranosyl)delphinidin. The CD of the blue petals of the phacelia showed a strong negative Cotton effect and that of the suspension of the colored protoplasts was the same, indicating that the chromophores of phacelianin may stack intermolecularly in an anti-clockwise stacking manner in the blue-colored vacuoles. In a weakly acidic aqueous solution, phacelianin displayed the same blue color and negative Cotton effect in CD as those of the petals. However, blue-black colored precipitates gradually formed without metal ions. A very small amount of Al(3+) or Fe(3+) may be required to stabilize the blue solution. Phacelianin may take both an inter- and intramolecular stacking form and shows the blue petal color by molecular association and the co-existence of a small amount of metal ions. We also isolated a major anthocyanin from the blue petals of Evolvulus pilosus and revised the structure identical to phacelianin. 相似文献
49.
Ferric ions involved in the flower color development of the Himalayan blue poppy, Meconopsis grandis 总被引:1,自引:0,他引:1
The Himalayan blue poppy, Meconopsis grandis, has sky blue-colored petals, although the anthocyanidin nucleus of the petal pigment is cyanidin. The blue color development in this blue poppy involving ferric ions was therefore studied. We analyzed the vacuolar pH, and the organic and inorganic components of the colored cells. A direct measurement by a proton-selective microelectrode revealed that the vacuolar pH value was 4.8. The concentrations of the total anthocyanins in the colored cells were around 5mM, and ca. three times more concentrated flavonols were detected. Fe was detected by atomic analysis of the colored cells, and the ratio of Fe to anthocyanins was ca. 0.8 eq. By mixing the anthocyanin, flavonol and metal ion components in a buffered aq. solution at pH 5.0, we were able to reproduce the same blue color; the visible absorption spectrum and CD were identical to those in the petals, with Fe(3+), Mg(2+) and flavonol being essential for the blue color. The blue pigment in Meconopsis should be a new type of metal complex pigment that is different from a stoichiometric supramolecular pigment such as commelinin or protocyanin. 相似文献
50.
The bHLH transcription factor MdbHLH3 promotes anthocyanin accumulation and fruit colouration in response to low temperature in apples 总被引:1,自引:0,他引:1