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传统中药植物羌活的种子因具有休眠限制了其人工驯化和栽培种植。为了解析羌活种子休眠解除过程的代谢物变化,筛选休眠解除关键化合物,对羌活种子进行冷暖层积预处理150 d,并对预处理的种子进行低温层积处理110 d,以及ABA抑制剂氯定酮(FL)和GA3(GA)处理,用UPLC-MS/MS对处理过程的羌活种子进行代谢物分析。结果表明:羌活种子整个处理过程分为3个阶段,0—60 d、90—(150+30) d、(150+60)—(150+110) d。其中,预处理+低温层积处理(150+60) d和(150+110) d 的羌活种子已具备萌发能力。t[1] 主成分所代表的化合物是预处理0、15、60、90、120 d的胚发育处理过程发生主要变化的化合物。t[2] 主成分所代表的化合物主要在生理休眠解除过程发生变化。差异分析发现,列当醇乙酸酯是一种独脚金内酯化合物,在种子休眠解除过程发生显著积累。其中,FL处理后列当醇乙酸酯的生物合成水平升高12.1倍,而低温层积处理后其合成水平升高28.5倍。因此,推测列当醇乙酸酯含量变化对羌活种子休眠解除非常关键。研究结果可为羌活种子休眠解除机理研究提供理论基础,对中药羌活的产业发展具有重要的实践意义。 相似文献
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Soil profiles with different vegetation, developed on igneous rock-derived areas in Northern Kyushu have been sampled at 13 locations and analyzed for total Hg with a flameless atomic absorption spectrometer. The associated parent rock was also analyzed. The Hg levels of each rock sample were too low, not exceeding 10 ppb, to exert a significant effect within the profiles on the total Hg content. The Hg content was generally higher in the soil than in the underlying rock, irrespective of the depth of the horizon. Surface enrichment of Hg was observed at most of the sample sites, some paddy fields in particular, resulting in steep concentration gradient down the profiles. The total Hg in all the surface horizons ranged from 459 to 64 ppb with a mean of 197 ppb. Obviously, mercurial application in recent years was a principal factor above all with regard to the establishment of the elevated Hg levels in the upper soil horizon under cultivation. Man-made loading of this element, probably through rain, was indicated even in the soils under natural vegetation, after taking into account a possible residual Hg concentration in the soil formation process. A close relationship in the profile distribution pattern between total Hg and organic matter contents was observed. This fact, in conjunction with the results of pyrolysis studies, did suggest that a large proportion of the total Hg in these soils could be firmly held by chemical forces, very likely as highly insoluble organic complexes. 相似文献
105.
Jahangir Abedi-Koupai Jaleh Varshosaz Mahsa Mesforoosh Amir Hossein Khoshgoftarmanesh 《Journal of plant nutrition》2013,36(8):1130-1138
There have as yet been no detailed studies of micronutrient release from polymer coated fertilizers (PCFs). In this research, slow release microcapsules containing iron fertilizer was made and its release pattern evaluated. Three polymers ethyl cellulose (EC), glycerol mono stearate (GMS) and Compritol 888 ATO, were mixed with avicel and lactose and the microcaopsules were made by extrusion/spheronization method. The dissolution test carried out to determine the Fe release rate versus time. The results showed that, microcaopsules containing Compritol 888 ATO, released iron ions slower than that of EC and GMS. The release rate reached 85% after 7 days. In order to reduce the release rate, these microcaopsules were coated with ethylene vinyl acetate (EVA) polymer by dip coating method. It is concluded that the combination of matrix type formulation and the coating with EVA polymer caused a significant decrease in the release rate of iron. 相似文献
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通过乙酸纤维素薄膜电泳,分离了8种鱼类的血清蛋白质成份并测定了其各组成份的相对含量。着重比较了γ球蛋白含量的差异性。 相似文献
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为了研究镉对大鼠肝细胞系(BRL 3A细胞)DNA及线粒体损伤的作用,本研究选用0、10、20、40 μmol/L的醋酸镉分别作用于BRL 3A细胞12h,利用四氮唑蓝比色分析法(MTT法)测定细胞存活率,显微镜观察各组细胞形态,通过彗星试验法检测细胞DNA的损伤,用透射电镜观察细胞线粒体超微结构,并检测细胞Caspase 3,9的活力.结果显示,随镉浓度的增大(10~40 μmol/L),BRL 3A细胞存活率降低,拖尾率、尾长、尾部DNA含量、细胞Caspase 3,9的活力和线粒体变形肿胀以及空泡现象均呈增加趋势;表明镉可致BRL 3A细胞DNA及线粒体损伤,并呈剂量依赖关系. 相似文献
109.
[目的]建立宽叶缬草根挥发油中乙酸龙脑酯的气相色谱测定法。[方法]以萘为内标物,以浓度5%苯基甲基聚硅氧烷为固定相的弹性石英毛细管柱(30 m×0.25 mm,0.25μm)为色谱柱;检测器为FID检测器;检测器温度为250℃;气化室温度为200℃;柱温为150℃;载气为氮气;尾吹30 ml/min;进样量2μl。[结果]在色谱条件下,乙酸龙脑酯与内标物萘及其他挥发性成分的分离效果良好,乙酸龙脑酯浓度在0.393~3.146 mg/ml范围内与峰面积的线性关系良好(R=0.999 3),平均加样回收率为97.48%,RSD为1.1%(n=9)。[结论]该方法灵敏、准确、重现性好,可用于宽叶缬草根挥发油的质量控制。 相似文献
110.
The effects of host-plant volatiles (HPVs) on male oriental fruit moth, Grapholita molesta (Busck) (Lepidoptera: Tortricidae), and response to sex pheromone trap were studied in a pear orchard. Two HPVs compounds, (Z)-3-hexenyl acetate and 1-undecanol, combined with sex pheromone of G. molesta in traps were tested. The results showed that most of the male moths were captured in the traps baited with the sex pheromone combined with these two HPVs compounds than by the pheromone alone. Also, more males were captured by the trap containing pheromone plus (Z)-3-hexenyl acetate than by the one containing 1-undecanol. It appeared that these HPVs act as sex pheromone synergists to enhance the attraction of male G. molestato pheromone traps, since males were not captured in the traps baited only with (Z)-3-hexenyl acetate and/or 1-undecanol. 相似文献