92 resultados para Maxim gun.
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在干旱气候背景下的毛乌素沙地,干旱、风沙是十分突出的环境胁迫因子。植物的生存与繁衍受到这些因子的强烈作用。在这里生存繁衍的许多克隆植物,在长期的生态适应与进化中,形成了有效的生态适应机制来克服沙地环境的不利影响。本研究选择在毛乌素沙地广泛分布的根茎型克隆植物羊柴(Hedysarum laeve Maxim.)和拂子茅(Calamagrostis epigejos (L.) Roth.)为实验对象,运用实验生态学的方法与途径,来探讨它们对环境因子的适应机制。 羊柴为毛乌素沙地的主要固沙植物与优良豆科牧草,在该地区广泛用于飞播和直播种植。对毛乌素沙地区域生态环境建设与畜牧业经济发展起到了重大作用。在毛乌素沙地,水分短缺是植物生长和繁殖的重要限制因子。同时,受地形、生物、基质等因素的影响,毛乌素沙地的水分往往呈异质性的空间分布。羊柴克隆的相连分株极有可能处于异质性水分供应的不同生境位点上。因而,相连的羊柴分株能否对异质性水分供应发生反应,以及反应的耗一益状况,是羊柴克隆对干旱与水分异质性生态适应的基本问题。为此,采用人工设置异质性水分供应的方法,研究了一对相连的羊柴成年克隆分株对水分异质性的反应及反应的耗一益状况。结果显示:分株的水分供应状况,对相连的另一分株的生长有着显著的影响。当生长于低水分供应土壤中的分株与生长于高水分供应土壤中的分株相连接时,此分株的地上植株、根系、新生根茎的产生都有显著的提高,生物量分配与同质高土壤水分供应的分株无显著差异;而同时,与此分株相连的、处于高水分供应土壤中的分株在生长上却无明显的减弱,并且将明显多的生物量分配到地下根系。这表明:分株间发生着明显的水分共享,相连的克隆分株通过水分共享对异质性水分供应发生反应:并且水分共享使处于低水分供应土壤中的羊柴分株显著获益而并不显著地牺牲另一处于高水分供应土壤中的羊柴分株的生长。水分共享可能是羊柴克隆对沙地水分异质性的生态适应机制之一。 风积沙埋在毛乌素沙地生态系统中频繁发生,直接影响着种子发芽后,幼苗的存活与成功定居。因而,对传播到沙地中的植物种具有选择作用。羊柴在近数十年来被大量地用于沙地飞播,以防风固沙重建沙地植被。羊柴在种子萌发后,幼苗很有可能遭受沙埋。为了探讨羊柴幼苗对沙埋的反应,对一周龄、二周龄的羊柴幼苗进行了为期6周的人工沙埋实验,实验结果显示:沙埋对羊柴幼苗的存活、生长影响极为显著,重度沙埋(沙埋深度达到或超过幼苗的高度)可使大量或全部羊柴幼苗死亡;一定深度的沙埋(沙埋深度不超过幼苗株高)羊柴幼苗不仅可以全部存活,而且其整株生物量、叶片生物量、根系生物量以及相对生长率都相应地高于非沙埋的对照(即:不沙埋),而且新生叶片的产生要显著地多于不沙埋的对照。与非沙埋的对照相比,一定深度的沙埋并不显著地改变羊柴幼苗的生物量分配格局,其株高也不发生明显的变化。根据本实验的结果,在飞播羊柴时最好先在流沙和半流沙上设置一些人工固沙、阻沙的设施,以避免羊柴幼苗遭受重度沙埋,降低其定居和形成种群的风险,促进其形成种群,提高飞播成效。 在本研究的实施地一毛乌素沙地,环境胁迫与扰动经常发生,异质性的生境条件有着广泛的分布。严酷的生存环境与异质性,为植物采取多样的生态适应策略提供了前提条件。克隆植物的相连分株间是否发生资源共享以及资源共享的时空格局具有种类特异性。拂子茅为根茎型多年生禾草。其根茎细长,在分株建立后并不随分株的年龄的增加与体形的增大而发生明显的加粗生长。为了探讨拂子茅在异质性水分环境中的表型差异,对拂子茅由母株、子株组成的分株对给予了高水、低水两种不同的异质性水分处理。实验结果表明:水分供应状况直径影响着拂子茅的分株生长表型。在高水条件下,拂子茅的分株能产生多的根茎、新生 后代分株,并将生物量主要用于地上部分生长,从而积累多的地上生物量;在低水条件下,拂子茅分株产生较少的根茎与新生后代分株,并且分配到根系的生物量明显增大。在具有一定对比度的异质性水分环境中,拂子茅分株并不因与其相连的分株所处的水分供应状况而在根茎生长、新生后代分株的产生和生物量分配等特征上,与同质环境中的具有相同水分供应状况的分株表现出有明显的差异。这些结果揭示:拂子茅仅以分株的形式对异质性水分在表型上发生反应;相连的克隆分株在向顶向和向基向这两个基本方向上,不能对另一分株的水分供应状况在生长表型上发生反应,它们在水分关系上可能是相互相对独立的。分株的相对独立有利于在气候干旱、扰动强烈的沙地环境中实现风险分摊,提高基株的存活机率。 可以推断:处于同一环境中的不同克隆植物种在长期的进化中,也可以选择截然不同的生态策略来适应环境。
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浑善达克沙地是我国北方干旱半干旱区的主要沙地和严重荒漠化地区之一。同时也是我国内陆沙尘的主要源区之一。研究当地植物对沙地环境的适应方式有助于当地的荒漠化治理,加快生态环境恢复。本文应用(温室和野外)实验生态学方法研究了沙地植物对水分、沙埋和养分异质性环境的生态适应对策。 浑善达克沙地属于半干旱区域。在一次降雨过后,适合植物生长的湿沙层逐渐下降,或者说不适合植物生长的干沙层逐渐加厚。为了能够有效地从沙层中获得水分,植物的根系的伸长的速度必须大于湿沙层下降的速度。因此,当地分布的植物的根系则应该具有相应的形态、生长和生物量投资方面的可塑性。羊柴(Hedysarum laeve Maxim. (Leguminosae) )是当地的主要半灌木和固沙植物。我们研究了羊柴幼苗对不同土壤含水量和不同模拟降雨量的反应格局,以及移动沙丘生长季节的土壤含水量变动规律。发现,大于3%土壤含水量适合羊柴幼苗生长。最适土壤含水量为12%-20% 。在生长季节早期,羊柴幼苗比较容易在沙丘上定居。如果没有充分的后续降雨的话,萌发后的幼苗在沙丘顶部、落沙坡中部和后部定居比较困难。降雨量越大,根系越深、总根长越大、根系直径越大、侧根越多、根冠比越低。 在干旱半干旱区域的沙地,种子萌发的时间和地点对于植物的定居和存活具有关键作用。通过温室实验,研究了小叶锦鸡儿和羊柴的种子萌发和出苗对不同深度的沙埋的反应,及其与种子大小的关联。结果表明,小叶锦鸡儿和羊柴的种子萌发和出苗对浑善达克沙地的自然生境表现出相似的生态适应。这两个种的种子萌发的适宜温度为10-15ºC, 这是当地春季的平均温度。由于这两个种的种子萌发是光敏感的,所以它们的种子萌发受土壤含水量和光照强度二者之间的平衡调节。2 cm 的较浅沙埋最有利于种子萌发和出苗。种子埋得越深,种子的萌发率和出苗率越低,更多的种子受胁迫休眠保存在土壤中作为种子库。不同大小的种子的不同萌发能力也是一种重要的生态适应,这可以调节种子在合适的时间和合适的沙埋深度萌发和出苗。 冰草(Agropyron cristatum (L.) Gaertn)是浑善达克沙地植物群落中占优势的多年生根茎草本植物之一。种子在合适的地点和时间萌发以及幼苗在合适的地点和时间生长,对于冰草在沙地环境条件下生存和分布具有重要意义。本文研究了浑善达克沙地4-10月份土壤含水量变动情况和冰草种子萌发、出苗和幼苗生长对土壤含水量的响应。结果表明,4月下旬至5月上中旬的土壤含水量对冰草种子萌发、出苗和定居极为关键。控制条件下,冰草种子萌发的最适土壤含水量是12%-20%,出苗以及幼苗生长的最适土壤含水量是12%-16%。当土壤含水量低于3%,冰草种子不能萌发,土壤含水量低于6%时,幼苗不能出土和定居。当土壤含水量达到16%时,冰草幼苗生物量有所下降。在6%-8%的土壤含水量条件下,植株将更多的生物量投资于根的生长。 本文对浑善达克沙地低湿滩地、滩地-风沙沉积过渡区到风沙沉积区的赖草(Leymus secalinus (Georgi) Tzvel.)分株数、地上生物量、土壤水分和养分异质性进行了研究。结果表明,从低湿滩地、滩地-风沙沉积过渡区到风沙沉积区,随着土壤养分的降低,赖草分株数和地上生物量反而增加。赖草的分株数在三种生境中都存在空间自相关。并且,从低湿滩地、过渡区到风沙沉积区空间自相关的变程逐渐增加。地上生物量同样存在空间自相关,但变程以过渡区最大,风沙沉积区最低。土壤水分仅仅在风沙沉积区存在空间自相关。在三种生境条件下,土壤全氮和有机质的空间分布格局相似,都在低湿滩地和过渡区存在空间自相关且变程相似。在风沙沉积区不存在空间自相关。赖草的空间分布格局在低湿滩地为偏离随机适度聚集的分布格局,在过渡区近似于聚居分布,而在风沙沉积区为均匀分布格局。 豆科锦鸡儿属(Caragana )植物因其可以生物固氮而在草原生态系统当中具有特殊的地位。定量分析小叶锦鸡儿(Caragana microphylla )灌丛在浑善达克沙地不同生境条件下的分布格局,有助于理解植被与土壤养分循环之间的关系和合理制定退化沙地的恢复对策。本文采用地统计学中的半方差分析和分形分析两种方法研究了浑善达克沙地小叶锦鸡儿灌丛的空间分布格局,分析了不同生境中小叶锦鸡儿灌丛的植被、土壤水分和养分间的相关性。结果表明(1)小叶锦鸡儿灌丛在三种生境条件下(滩地、固定沙丘和半固定沙丘)的盖度、土壤有机质和全氮的空间分布符合球状模型,空间自相关显著;(2)土壤pH值在滩地和固定沙丘的空间分布符合球状模型且空间自相关显著,但在半固定沙丘空间自相关不显著;(3)土壤水分在三种生境中的空间分布都符合线性模型,空间自相关显著。(4)植被的变异尺度(变程)小于各个土壤要素的变异尺度。植被(小叶锦鸡儿灌丛)的分布和形成过程决定了土壤养分的分布和形成过程。当地的豆科植物在养分“沃岛”现象的形成中起了重要作用,合理的利用和布局当地的豆科植物,可以更加有效地补充草地生态系统的养分,从而有利于加快当地生态系统的恢复进程。
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毛乌素沙地与浑善达克沙地为我国著名的沙地。本文以毛乌素沙地荒漠化防治中常用的飞播植被恢复技术为突破口,研究飞播采用的主要植物种种子萌发与幼苗出土对沙埋与水分的响应,以改善植被飞播恢复技术。近年来浑善达克沙地快速发展的荒漠化进程引起了人们的极大关注,本文应用统计方法对浑善达克沙地荒漠化成因进行了系统研究。 羊柴(Hedysarum leave Maxim.)、柠条(Caragana korshinskii Kom.)、籽蒿(Artimisia sphaerocephala Krasch)与油蒿(Artimisia ordosica Krasch.)为鄂尔多斯高原广泛分布的植物种,也是该地区飞播选用的主要植物种。通过温室实验,对四种植物萌发特性及出苗与水分和沙埋深度的关系进行研究,阐明了种子萌发的最适水分条件和沙埋深度。四种植物种子萌发与出苗最适宜的供水量都接近于当地生长季的平均降水量 (50mm/month);最适宜的沙埋深度为0.5cm-1cm, 羊柴、柠条、籽蒿和油蒿的沙埋深度分别为:0.5、1.0、0.5和0.5cm。过多的水分和过深的沙埋显著降低种子萌发与出苗,反映了四种植物对沙区环境的生态适应。基于实验结果及当地气候特点,建议将鄂尔多斯地区的飞播时间由6月初提前至5月中下旬,以提高飞播植物的出苗率。 近年来浑善达克沙地荒漠化的发展呈现加剧的趋势。通过对位于浑善达克沙地中心区正蓝旗的自然和社会因子变化趋势的研究寻求该区荒漠化发生发展的原因,应用数理统计方法对正蓝旗一些重要的气候及经济因子在近40年的变化过程进行了系统分析,发现过度放牧及人口的急剧增加是导致正蓝旗乃至浑善达克地区荒漠化加剧的主要原因。同时,温室效应造成的全球增温也是重要的诱因之一。基于上述分析,对浑善达克沙地的荒漠化防治工作提出了一些具体的建议和措施。
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利用RNAi改良大豆油脂品质 大豆[Glycine max (L.) Merr.]起源于中国,栽培历史悠久,是重要的粮食作物, 同时也是植物油和蛋白的重要来源。随着经济的发展和生活水平的提高,人们不但对大豆的需求量大大增加,同时对大豆的品质也提出了更高的要求。近年来,我国大豆进口量逐年攀升,已远远超过本国生产量。国外转抗除草剂转基因大豆大面积种植大大降低了生产成本,直接影响了我国大豆生产。因此,提高产量和改良品质是当前中国大豆生产所面临的重要课题。基因工程是大豆品种改良更为有效和快速的方法,但是由于历史原因我国的大豆转基因育种与发达国家尚存在一定差距,对我国的大豆生产贡献十分有限。因此,建立高效的大豆转化体系,加强大豆基因工程研究和育种是解决大豆面临困境的关键。 本研究的目的是以我国主要栽培大豆品种(黑农、合丰和东农等)为材料,利用GUS(β-glucuronidase)报告基因和RNAi技术,建立高效的大豆基因转化体系和基因功能研究体系。为大豆产量和品质基因工程改良提供技术手段和理论基础。结果如下: 以大豆下胚轴为外植体,对分生组织产生不定芽的频率进行了研究。培养基中添加高浓度BAP(6-benzylaminopurine)可以诱导外植体分生组织增殖产生不定芽的发生率;在培养基中添加银离子可以明显地促进大豆单个外植体多芽的产生,使得诱导不定芽总数目显著增加;不同基因型大豆再生不定芽能力有着较大区别,黑农44,黑农37,合丰35,合丰39等品种再生能力强;相对于大豆子叶节等再生系统,大豆下胚轴体系具有高效高频的再生特点(总的再生频率高于80%),且重复性好,容易操作。 以大豆下胚轴为外植体,用含有GUS报告基因的根癌农杆菌对其进行遗传转化,并重点对农杆菌菌液浓度、农杆菌侵染时间、乙酰丁香酮(AS)和抗氧化剂浓度等因素对农杆菌大豆转化效率的影响进行了研究。组织化学染色结果显示GUS基因在外植体顶端表达强烈,表达位置主要位于初生芽基部周围的分生组织。 农杆菌浸染时间以 4h 为最佳,此时的GUS瞬时表达频率可达73.0%;培养基中添加浓度为200μmol/L的乙酰丁香酮,可以显著增加GUS瞬时表达频率。抗氧化剂可以显著降低共培养阶段外植体的褐化和坏死率,进而显著提高农杆菌转化效率。用根癌农杆菌转化大豆下胚轴的方法得到了表达GUS基因转基因大豆株系。 利用大豆油酸去饱和酶基因(FAD2-1;Genbank, L43920)在第315-852碱基之间的基因片断构建了反向重复的RNAi表达载体,以农杆菌介导大豆下胚轴转化方法进行转化,并且获得转基因植株。经过PCR,Southern杂交和转基因后代的脂肪酸分析,表明沉默结构已经成功整合到大豆基因组中,并成功抑制了内源基因的表达。与栽培大豆品种相比较,转基因大豆种子的脂肪酸组成发生显著变化,油酸含量由栽培大豆的18.1%增加到71.5%¬-81.9%;亚油酸含量从栽培大豆的46.4%降到了约3.4%。 栽培大豆种子中油酸去饱和比率(ODP, oleic desaturation proportion)为0.76 到 0.84,转基因大豆种子的油酸去饱和比率降为0.06-0.26,表明Δ12-去饱和酶活性降低了74%-94%。上述结果表明,我们构建的RNAi反向重复序列沉默结构高效地抑制了大豆种子FAD2-1基因。 在本研究中,我们通过外源GUS基因的表达和内源FAD2基因的抑制,成功地建立了以大豆下胚轴为外植体的高效农杆菌介导大豆转化体系,并获得了相应的转基因株系。本研究对我国大豆品种基因工程改良以及进一步大豆功能基因组研究有重要参考价值。 四合木茎积累三脂酰甘油特征 四合木(Tetraena mongotica Maxim)是蒺藜科(Zygophyllaceac)四合木属唯一的种,是地球上最具代表性的古老残遗濒危珍稀植物。由于四合木极易燃烧,当地居民称其为“油柴”。 通过对四合木内可能存在的“油”成分进行了分析,我们发现其茎组织含有大量的三脂酰甘油(Triacylglycerols),含量达到46 mg/g DM。在韧皮部中更高,达到90 mg/g DM。我们通过半薄切片对四合木中三脂酰甘油在不同组织的分布和存在形式进行了研究,发现三脂酰甘油主要以油体形式存在于木质部和韧皮部的薄壁组织中。在韧皮部中,几乎所有的薄壁细胞都含有大量的油体。 三脂酰甘油在植物的生长发育中起着非常重要的作用。作为植物生长发育所需的碳源和能量,三脂酰甘油一般储存在植物的种子和果实中。虽然也有关于其在茎和叶中发现的报道,但是含量很少。四合木茎组织含有大量的三脂酰甘油,这种现象可能与四合木茎中存在茎特异油脂合成酶系统有关。因此,克隆相关基因并在作物中表达,将对能源植物的开发具有重要意义。
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Trichosanthin (TCS) is a ribosome-inactivating protein from root tubers of Trichosanthes kirilowii Maxim. In this paper, the effects of TCS on the viability of human peripheral blood immunocytess, on the proliferation of lymphocytes, and its cytotoxicity to twelve cell lines of lymphoma or leukemia had been observed. TCS at high concentration (>12.5 mu g/ml) affected the viability of human B lymphocytes, but not that of human peripheral blood mononuclear cells (PBMCs), T lymphocytes and granulocytes. Human peripheral blood-derived monocytes/macrophages were highly sensitive to TCS (ID50 at 1.70 mu g/ml). TCS suppressed lymphocyte proliferation stimulated by Concanavalin A (Con A) or lipopolysaccharide (LPS). Human T cell lines and macrophage cell lines were more sensitive (ID50 < 0.9 mu g/ml) to TCS than B cell lines and myeloid lines. These results suggest that selective cytotoxicity of TCS to human macrophages/monocytes may be implicated in anti-HIV activity, and that selectively killing some leukemia-lymphoma cells by TCS merit further evaluation in treatment of some lymphoma and leukemia.
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We report on the comparative studies of epitaxial SiC films grown on silicon-on-insulator (SOI) and Si bulk substrates. The silicon-over-layer (SOL) on the SOI has been thinned down to different thicknesses, with the thinnest about 10 nm. It has been found that the full-width-at-half-maxim in the X-ray diffraction spectrum from the SiC films decreases as the SOL thickness decreases, indicating improved quality of the SiC film. A similar trend has also been found in the Raman spectrum. One of the potential explanations for the observation is strain accommodation by the ultra-thin SOI substrate. (c) 2005 Elsevier B.V. All rights reserved.
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We present some results on the effect of initial buffer layer on the crystalline quality of Cubic GaN epitaxial layers grown on GaAs(100) substrates by metalorganic chemical vapor deposition. Photoluminescence and Hall measurements were performed to characterize the electrical and optical properties of cubic GaN. The crystalline quality subsequently grown high-temperature (HT) cubic GaN layers strongly depended on thermal effects during the temperature ramping process after low temperature (LT) growth of the buffer layers. Atomic force microscope (AFM) and reflection high-energy electron diffraction (RHEED) were employed to investigate this temperature ramping process. Furthermore, the role of thermal treatment during the temperature ramping process was identified. Using the optimum buffer layer, the full width at half maxim (FWHM) at room temperature photoluminescence 5.6 nm was achieved. To our knowledge, this is the best FWHM value for cubic GaN to date. The background carrier concentration was as low as 3 x 10(13) cm(-3). (C) 2000 Published by Elsevier Science S.A. All rights reserved.
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The mode frequencies and quality factors are calculated for the equilateral triangle semiconductor microlasers with sinusoidal and random Gaussian sidewalls. The results show that the modes can still have high Q-factors.
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The semiconductor microlasers with an equilateral triangle resonator which can be fabricated by dry etching technique from the laser wafer of the edge emitting laser, are analyzed by FDTD technique and rate equations. The results show that ETR microlaser is suitable to realize single mode operation. By connecting an output waveguide to one of the vertices of the ETR, we still can get the confined modes with high quality factors. The EM microlasers are potential light sources for photonic integrated circuits.
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We present some results on the effect of initial buffer layer on the crystalline quality of Cubic GaN epitaxial layers grown on GaAs(100) substrates by metalorganic chemical vapor deposition. Photoluminescence and Hall measurements were performed to characterize the electrical and optical properties of cubic GaN. The crystalline quality subsequently grown high-temperature (HT) cubic GaN layers strongly depended on thermal effects during the temperature ramping process after low temperature (LT) growth of the buffer layers. Atomic force microscope (AFM) and reflection high-energy electron diffraction (RHEED) were employed to investigate this temperature ramping process. Furthermore, the role of thermal treatment during the temperature ramping process was identified. Using the optimum buffer layer, the full width at half maxim (FWHM) at room temperature photoluminescence 5.6 nm was achieved. To our knowledge, this is the best FWHM value for cubic GaN to date. The background carrier concentration was as low as 3 x 10(13) cm(-3). (C) 2000 Published by Elsevier Science S.A. All rights reserved.
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本学位论文报道了作为传统藏药材广泛使用的西藏产雪莲花化学成分的研究。论文由五章组成,第一章是三种西藏产雪莲花的化学成分的系统分离纯化和结构鉴定;第二章为西藏产雪莲花化学成分的液-质及串联质谱联用分析;第三章提出了以HPLC和TLC为检测方法的雪莲花药材质量标准草案;第四章给出了对西藏产雪莲花挥发油化学成分的气-质联用分析结果;第五章概述了雪莲花的化学成分及药理研究进展。 第一章包括三个部分。第一部分报道了绵头雪莲花(Saussurea laniceps Hand.-Mazz.)全草乙醇提取物化学成分的分离鉴定。采用正相硅胶柱层析及凝胶柱层析等分离方法,从西藏产绵头雪莲花的乙醇提取物中共分离鉴定出15个化合物。其中11个化合物为首次从该植物中分离得到,当中2个化合物系在凤毛菊属植物中首次发现。第二部分报道了水母雪莲花(Saussurea medusa Maxim.)全草乙醇提取物的化学成分。采用正、反相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出15个化合物,其中1个为新化合物,另有4个化合物为首次从该植物中分离得到。新化合物结构通过质谱和一维及二维核磁共振等波谱解析方法及碱水解反应确定为巴豆酰基-高车前苷(M-7)。第三部分报道了三指雪莲花 (Saussurea tridactyla Sch.-Bip. ex Hook. f.)全草乙醇提取物的化学成分。采用正相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出7个化合物,其中1个化合物为首次从该植物中分离得到。 第二章也包括三个部分。首先是采用液-质联用(HPLC-DAD-ESI-MSn)分析方法,对7个西藏不同产地的三指雪莲花化学成分进行了分析,通过与标准品的 UV和MS数据比较,共鉴定出14个峰,并对其中8个共有成分进行了定量测定。其次是关于八种西藏产雪莲花化学成分的液-质联用(HPLC-DAD-ESI-MSn)分析,通过与标准品的UV和MS数据比较,共鉴定出15个峰,并对其中8个共有成分进行了定量检测。最后通过对八种西藏产雪莲花主要化学成分的多级串联质谱(ESI-MSn)分析,快速、灵敏地鉴定出10个黄酮和3个香豆素化学成分。 第三章同样包括三个部分。首先是以绵头雪莲花中主要香豆素成分东莨菪素和伞形花内酯为对照品,通过TLC定性检测和HPLC含量测定,草拟出较严谨的药材质量标准。其次是将绵头雪莲花、三指雪莲花和雪兔子作为一个药材看待,草拟了以东莨菪素和伞形花内酯的TLC检测为指标的药材质量标准。最后是针对水母雪莲花,以主要黄酮成分芹菜素-7-O-b-D-葡萄糖苷为对照品作TLC检测,并草拟出该药材的质量标准草案。 第四章报道了西藏产雪莲花挥发油的化学成分分析。采用传统水蒸气蒸馏法分别从八种雪莲花全草中提取挥发油,利用气相色谱-质谱联用技术分别从水母雪莲花、绵头雪莲花、槲叶雪莲花、云状雪兔子、拉萨雪兔子、小果雪兔子、雪兔子和三指雪莲花中分别鉴定出83、83、56、34、21、20、24和20个化学成分,分别占其挥发油总量的70.7%、76.0%、82.2%、55.4%、49.7%、70.4 %、76.2%和 76.7%。 第五章为综述,总结和概括了雪莲花的化学和药理研究进展。 The dissertation reports the investigation of the chemical constituents of the genus Saussurea. Quite a lot of species in this genus are traditional Tibetan medicinal plants, and hence have been widely used in traditional Tibetan medicine. This dissertation consisted of five chapters. The first chapter is on the chemical constituents of three Saussurea plants. The second section is about the analysis of chemical constituents of Saussurea plants using HPLC-MS and ESI-MS/MS. In the third chapter, we proposed quality-control standards for the Genus Saussurea based on TLC (thin layer chromatography) and HPLC. The fourth chapter is about chemical compositions of the essential oil from the whole plant of Saussurea plants. The last chapter reviews the research progress of the Genus Saussurea. The first chapter consists of three parts. The first part is about chemical constituents of ethanol extracts from whole plant of Saussurea laniceps Hand.-Mazz. Fifteen compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. Among them, eleven compounds were isolated from this plant for the first time, and two compounds were isolated from Genus Saussurea for the first time. The second part is about chemical constituents of ethanol extracts from whole plant of Saussurea medusa Maxim. Fifteen compounds were isolated by column chromatography on normal phase, reversed phase silica gel and Sephadex LH-20. Five of them were isolated from this plant for the first time, and there is one new flavonoid glucoside which was identified as 6″-O-crotonoyl-homoplantaginin (M-7) based on the evidence of one- and two-dimensional nuclear magnetic resonance, mass spectrometry analysis, and alkaline hydrolysis reaction. The last part is about chemical constituents of ethanol extracts from whole plant of Saussurea tridactyla Sch.-Bip. ex Hook. f.. Seven compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. There is one compound which was isolated from this plant for the first time. The second chapter consists of three parts. In the first part, we analyzed the chemical constituents of S. tridactyla collected from seven different places in Tibet using HPLC-DAD-ESI-MSn. Fourteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds, among which eight common peaks were quantified. In the second part, we analyzed the chemical constituents of eight Saussurea species using HPLC-DAD-ESI-MSn method. Fifteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds and eight main peaks of them were quantified. In the last part, we analyzed the chemical compounds of the above eight Saussurea plants directly by ESI-MS/MS. Thirteen major compounds, including 10 flavonoids and 3 coumarins were easily rapidly identified. The third chapter consists of three parts. In the first part, we proposed a comparative high quality-control standard for S. laniceps, based on quality detection by TLC and quantity analysis by HPLC using two major compounds (umbelliferone and scopoletin) as standard compounds. In the second part, in viewing S. laniceps, S. tridactyla and S. gossypiphora as the members of one family of medicinal herbs, we suggested a quality-control standard based on the TLC detection of the two major compounds (umbelliferone and scopoletin). In the last part, we proposed a quality-control standard for S. medusa based on the TLC detection of its major component (apigenin 7-O-glucoside). The four chapter analyzed the chemical constituents of essential oil of eight Saussurea species. The essential oils were extracted from the whole plants of these samples with water stream distillation. By GC-MS analysis, we identified eighty-three compounds from S. medusa, eighty-three from S. laniceps, fifty-six from S. quercifolia, thirty-four from S. aster, twenty-one from S. kingii, twenty from S. simpsoniana, twenty-four from S. gossypiphora, and twenty from S. tridactyla respetively, which accounted for 70.7%, 76.0%, 82.2%, 55.4%, 49.7%, 70.4 %, 76.2% and 76.7% of the total essential oil, respectively. The last chapter reviews the research progress of the Genus Saussurea.
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本学位论文由两部分共3章组成。第一部分分别报道2种藏药唐古特瑞香和大果大戟化学成分的研究成果,从2种药用植物共分离鉴定了60个不同的化合物,其中12个为新结构,特别有意义的是发现了2个具有同一新骨架的二萜化合物。第二部分概述了大戟科植物多环二萜的研究进展。 第一部分包括第1和2章。在这2章中分别报道了唐古特瑞香(Daphne tangutica Maxim)和大果大戟(Euphorbia wallichii Hook. f. Fl)化学成分的分离纯化与结构鉴定。实验采用正、反相硅胶柱层析、薄层制备及HPLC等分离方法,从唐古特瑞香的根皮中共分离出32个化合物,通过红外、质谱及核磁共振等波谱方法鉴定了其中的31个,结构类型分别属于瑞香二萜类、木脂素类、香豆素类、苯丙素类及甾体类,其中有三个新的瑞香二萜型化合物,经波谱分析将它们的结构分别鉴定为1,2a-二氢-20-棕榈酰瑞香毒素、1,2a-二氢-5b-羟基-6a,7a-环氧-树脂大戟醇-14-苯甲酸酯及1,2b-二氢-5b-羟基-6a,7a-环氧-树脂大戟醇-14-苯甲酸酯,另外还有13个已知化合物为首次从该植物中分离得到。从大果大戟的根部共分离出33个化合物,鉴定了其中的30个,其主要成分为种类丰富的二萜,包括巨大戟烷型、续随子烷型、对映-阿替生烷型、对映-贝壳杉烷型、对映-松香烷型、ent-trachylobane型、对映-异海松烷型及一新骨架五环二萜ent-wallichane型,另外还有香豆素、甾体、三萜和一些简单的小分子化合物。其中新化合物有9个,经波谱分析将它们的结构分别鉴定为5-O-(2E,4E,6E)-癸三烯酰基-3,20-O-二乙酰基巨大戟醇、5-O-(2E,4Z)-癸二烯酰基-3-O-乙酰基-20-去氧巨大戟醇、3-O-(2E,4Z)-癸二烯酰基-5b,6b-氧-交京大戟醇、7-苯甲酰氧基-3,5,15-三乙酰基-续随子醇、ent-trachylobane-3-one-17-oic-acid、3α-羟基-对映-阿替斯-16-烯-14-酮、3α,6-二羟基-对映-异海松-7-烯-2,15-二酮、wallichanol A 和 wallichanol B,其中,wallichanol A 和 wallichanol B属于一新骨架类型的五环二萜。除此以外,另有13个已知化合物为首次从该植物中分离得到。 第2部分即第3章,首次概述了大戟属植物中多环二萜的化学和药理研究进展。 This dissertation is composed by two parts. The first part reports the phytochemical investigation of two Tibetan medicine plants, Daphne tangutica Maxim and Euphorbia wallichii Hook. f. Fl. Sixty different compounds including ten new compounds and two novel diterpenoids possessing a new carbon skeleton were isolated and identified. The second part is a review about the progress of studies on the polycyclic diterpeniods of the plant family of Euphorbia. The first part consists two chapters, which expatiate on the isolation and identification of chemical constituents from D. tangutica and E. wallichii. Thirty-one compounds were isolated from the root barks of D. tangutica by methods of column chromatography (silica gel, including reversed phase), preparative TLC and HPLC, and their structure were identified as nine daphnane diterpenes, six lignans, nine cumarin derivatives, five phenylpropanoid derivatives, a steroids and a benzoate on the basis of spectroscopic methods including IR, MS and NMR. Among them, three are new diterpenes with skeleton of daphnane and the structure were determined as 1,a-dihydro-20-palimoyl-daphnetoxin, 1,2a-dihydro-5b- hydroxy-6a,7a-epoxy-resiniferonol-14-benzoate and 1,2b-dihydro-5b-hydroxy- 6a,7a-epoxy-resiniferonol-14-benzoate. In addition, thirteen known ones were isolated from this plant for the first time. Isolation of the roots of E. wallichii yielded thirty compounds, twenty-four of them were elucidated as diterpenoids, which belong to different skeleton types of ingenol, lathyrane, ent-atisane, ent-kaurane, ent-abietane, ent-trachylobane, ent-isopimarane and a new pentacyclic skeleton ent-wallichane respectively. The remains including a cumarine, a triterpenoid, a steroid and three compounds with small molecule. Nine new compounds were characterized as 5-O-deca-2E,4E,6E- trienoyl-3,20-O-diacetylingenol, 5-O-deca-2E,4Z-dienoyl-3-O-acetyl-20- deoxyingenol, 3-O-deca-2E,4Z-dienoyl-jolkinol-5b,6b-oxide, 7-benzoyl-3,5,15- triacetyl-7-hydroxylathyrol, ent-trachylobane-3-one-17-oic-acid, 3α-hydroxy-ent- atis-16-en-14-one, 3α,6-dihydroxy-ent-isopimarane-7-en-2,15-dione, wallichanol A and wallichanol B, respectively, by means of comprehensive spectroscopic analysis. Among them, wallichanol A and wallichanol B were two notable novel pentacyclic diterpenoids processing a new rearranged carbon skeleton. And more, thirteen ones were firstly reported from this plant. The third chapter summarizes the research development on chemistry and pharmacology of polycyclic diterpenes from the plant family of Euphorbia for the first time.
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本学位论文由4章组成。第一章是论文的主体,报道了中药射干的化学成分研究。第二章是中药射干代用品川射干的化学成分研究,并附带报道了西番莲化学成分的研究结果。第三章是射干、川射干及西番莲提取物化学成分串联质谱分析的报道。第四章为综述,概述了射干及鸢尾属植物的化学成分和药理研究进展。 在第一和二章中分别报道了射干(Belamcanda chinensis (L.) DC.)、川射干 (Iris tectorum Maxim.)及西番莲(Passiflora incarnate L.)化学成分的分离纯化与结构鉴定。采用正、反相硅胶柱层析、凝胶柱层析、薄层制备及HPLC等各种分离方法,从三种药用植物中共分离出68个不同的化合物,其中61个的结构得 得以鉴定,另外4个化合物的结构正在鉴定中,3个由于量少且有点杂质未作进一步的鉴定。 中药射干(Rhizoma Belamcandae)为射干植物的干燥根茎,从中共分离出53个化合物,通过红外、质谱及核磁共振等波谱方法鉴定了包括12个新化合物在内的48个,结构类型分别属于iridal型三萜及其新颖的二聚体、异黄酮、黄酮及黄酮醇、香豆素、甾体、芳香酸和脂肪酸及其甘油酯等。新化合物中有两个异黄酮类化合物,其结构分别鉴定为5,7,8,4′-四羟基-6-甲氧基异黄酮和5,6-二羟基-4′-甲氧基异黄酮-7-O-β-D-吡喃葡萄糖苷;八个新的iridal型三萜化合物分别鉴定为鸢尾烯(L)、16-甲氧基鸢尾烯、16-去羟基鸢尾烯、2-(E)-16-去羟基鸢尾烯、16-去羟基鸢尾烯B、3-乙酰基-16-去羟基鸢尾烯、iristectoroneL和iristectoroneM;两个结构骨架新颖的双三萜,分别命名为射干素A和射干素B,其分离纯化的困难以及结构的新颖和复杂突显出该论文的科学意义。除这些新化合物外,还有9个已知化合物为首次从中药射干中分离得到。此外,从中药射干的代用品川射干中分离得到7个已知化合物,主要是黄酮类成分及iridal型三萜化合物,其中1个三萜化合物为从射干中分离鉴定的新成分。另外还从西番莲中分离出8个化合物,鉴定了其中的6个,主要为黄酮碳苷。 第三章是关于射干、川射干及西番莲提取物化学成分的ESI-MS-MS分析,在初步探讨了从这些植物中分离鉴定出的一些异黄酮及黄酮碳苷的质谱裂解规律基础上,通过质谱和串联质谱分析,定性和半定量地检测了射干和川射干中主要的异黄酮成分以及西番莲中的黄酮碳苷成分,为这些药材品质的快速鉴定提供了一种简便方法。 第四章概述了射干及鸢尾属药用植物的化学和药理研究进展,特别是对其中异黄酮及三萜类成分的研究进展进行了深入系统的综述。 This dissertation is composed by four chapters. The first and second chapter reports the phytochemical investigation of three medicine plants, Belamcanda chinensis (L.)DC., Iris tectorum Maxim. and Passiflora incarnate L. Sixty eight different compounds were isolated and sixty one of them were identified. The third chapter described rapid ESI-MS-MS analysis of B. chinensis, I. tectorum, and P. incarnate. The forth part is a review about the progress of studies on the chemical constituents from Belamcanda chinensis and Iris species. Fifty-three compounds were isolated from Rhizoma Belamcandae, the rhizomes of B. chinensis by the methods of column chromatography (normal and reversed phase silica gel, Sephadex LH-20), preparative TLC and HPLC. On the basis of spectroscopic methods including IR, ESI-MS, 1-D and 2-D NMR, forty eight of them were identified as seventeen flavonoids, seventeen tritepenoids, one cumarin, five steroids and some benzene derivative etc. Among them, the structures of twelve new compounds were elucidated as 6-methoxy-5,7,8,4′-tetrahydryoxyisoflavoe, 4′-methoxy-5,6-dihydroxyisoflavone-7-O-β-D-glucopyranoside, iristectorene L, 16-methoxyisoiridogermanal, 16-dehydroxyisoiridogermanal, 2-(E)-16-dehydroxy isoiridogermanal, 16-dehydroxyiristectorene B, 3-acetyl-16-dehydroxyisoiridoger- manal, iristectorone L, iristectorone M, belamcandene A and belamcandene B. Last two new compounds are dimer of triterpenoids with a novel carbon skeleton. Beside the new compounds, nine known ones were isolated from this plant for the first time. Isolation of I. tectorum yielded seven compounds. On the basis of spectroscopic methods including ESI-MS, NMR and the comparison with authentic samples, three of them were determined as isoflavone, two of them were triterpenoids, and other two were β-sitosterol and apocynin. All of them are known compounds except one of iridal type triterpenoid, 16-dehydroxyiristectorene B, which also obtained from B. chinensis as a new compound. Isolation of P. incarnate yielded eight compounds. Six of them were determined on the basis of spectroscopic methods including ESI-MS, NMR and the comparison with authentic samples. Four of them are flavone-C-gluconside, and two are steroids. The third chapter describes the tandem mass spectrometry (ESI-MS-MS) analysis of the isoflavonoids from B. chinensis and I. tectorum, as well as C-glycosyl-flavonoide from P. incarnate, in order to explore the rapid methodology of validating the quality of the herbs. In addition, the fractionation rules of some iosflavonoids and C-glycosyl-flavonoids were discussed. The fourth chapter summarizes the research development on chemistry and pharmacology of medicine plants of B.chinensis and Iris species.
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本学位论文首先报道了为解决低极性化合物的电喷雾质谱(ESI-MS)分析难题而建立的一种衍生化分析方法;然后从色谱-质谱联用分析、分离纯化和结构鉴定等方面分别报道了几种中藏药材的活性成分研究。论文由下述六章组成: 第一章报道了盐酸羟胺衍生化方法在电喷雾质谱 (ESI-MS) 分析中的应用。该方法利用盐酸羟胺和羰基成肟的快速反应,建立了针对三萜酮等含酮或醛羰基低极性化合物的ESI-MS 信号增强技术。此方法不仅可应用于增强羰基化合物的ESI-MS 质谱信号,还可检测化合物中羰基的个数以及辨别涉及羰基官能团的同分异构体。此外,通过简单的氧化反应,还可将该方法拓展到三萜醇、甾醇等含羟基的低极性化合物,增强它们的ESI-MS 信号。对比已报道的相关ESI-MS 增强质谱信号的衍生化方法,此方法有经济、实用、快速和简便的显著特点。 第二章是关于野生羌活及其栽培品种化学成分的色谱-质谱联用分析。对不同产地野生羌活生长过程中活性成分的动态变化、野生羌活不同形态部位和人工栽培羌活中的活性成分含量进行了HPLC 定量分析。结果表明主要活性成分羌活醇和异欧前胡素都随生长期存在规律性变化,羌活不同形态部位中的活性成分含量也有明显不同。这些实验结果有些较好地印证了传统中医的用药理论,有些也对羌活的传统使用方法提出了新的建议。 第三章介绍了几种传统中藏药材的色谱-质谱联用及串联质谱分析。通过GC-MS 方法,从藏药材长花党参挥发油中共分离鉴定出45 个化合物;利用HPLC方法测定了该藏药材中的主要化学成分——木犀草素的含量(0.7%);利用串联质谱技术,对西番莲和射干中的主要成分进行了快速鉴定,从西番莲中鉴定了4个黄酮碳苷;从不同产地的射干和川射干中鉴定了8 个主要异黄酮成分,其中包括一个未见报道的化合物。 第四章的内容为藏药材石莲叶点地梅的活性成分研究。从植物石莲叶点地梅(Androsace integra (Maxim.) Hand.-Mazz.) 乙醇提取物的正丁醇萃取部分共分离和鉴定了6 个化合物,利用MS 和NMR 等现代波谱学技术阐明了它们的结构:其中包括4 个三萜类化合物:分别是androsacin (1)、 ardisiacrispin A (2) 、saxifragifolin A (3) 和20(29)-lupen-3-one (4);一个神经酰胺:4-羟基-Δ8,9(Z)-鞘氨醇-2'-羟基正二十四碳酸酰胺(5);一个甾体类化合物:胡萝卜苷(6)。化合物1为新的13,28-epoxy-oleanane 型三萜皂苷,在其结构表征的过程中,采用LC-MS 进行糖分析,获得了值得推广的好结果。通过活性筛选发现化合物1~3 对HepG2肝癌细胞表现出不同程度的抑制活性,其中化合物2 活性最好,其IG50 为1.65μg/mL。 第五章是关于一些传统中藏药材的农药活性筛选。利用Syngenta 公司的活性筛选平台对68 种传统中藏药材醇提物进行了抗菌和除草的生物源农药活性筛选。结果表明所筛选的68 种植物提取物中,共有14 种样品表现出明显的除草/杀虫活性,其中水母雪莲花、松萝和茯神木等植物提取物还具有多种生物活性。活性成分还有待进一步追踪分离、纯化和结构鉴定。 第六章为文献综述,概述了羌活药材的研究进展。对羌活属及药用羌活植物从分类学、本草学、品质评价、人工栽培、化学成分及药理作用等方面进行了文献归纳和总结。 In this dissertation, an electrospray ionization mass spectrometry (ESI-MS) signal enhancement method, as well as the work of bioactive components study, HPLC-MS/MS application, bioassay screening, chromatograph separation and structure identification of the metabolites in several medicinal herbs have been reported. First chapter expounded a rapid, simple ESI-MS sensitivity enhancement method for detecting carbonyl groups in natural products has been developed by using hydroxylamine hydrochloride (NH2OH·HCl) as a derivatization reagent. We use the oxime formed during the derivatization reactions and its Beckmann rearrangement intermediates as a means of detecting the carbonyl groups originally present in these triterpenoids. In comparison with other derivatization methods in the literature, this method is simple, specific and can be used to detect carbonyl groups in triterpenoids which have low polarity and are poorly or non-ionizable. Moreover, it can also be used to detect hydroxyl groups by using the Dess-Martin periodinane (DMP) to convert primary and secondary hydroxyls into carbonyl groups. Chapter 2 reported an HPLC-MS method for analyzing the main bioactive compounds in both wild and cultured Notopterygium incisum. The results indicated that the main bioactive compounds varied through different seasons regularly, and in different commercial parts of this herb the content of these compounds also differed from each other. The quantitative analysis results showed that in the traditional commercial parts, the content of main chemical constitutes in Silkworm Notopterygium, Bamboo Notopterygium and Irregular-nodal Notopterygium are higher than that in Striped Notopterygium. This result is tally with the traditionally concept that the quality of Notopterygium, Bamboo Notopterygium and Irregular-nodal Notopterygium are better than that of Striped Notopterygium, which means that the quality of rhizomes is better than main roots. The chemical constituents of cultured N. incisum is reported for the first time in this dissertation and the analysis results showed some growth curves of chemical constituents in this plant, but still left some questions unanswered. Chapter 3 discussed the GC/LC-MS analysis of the traditional Chinese medicines Codonopsis thalictrifolis, Passiflora incarnate, Belamcanda chinensis and Passiflora incarnate. The main constituent, luteolin was isolated and identified from the traditional Tibet medicine of C. thalictrifolis. The quantitative analysis by HPLC has revealed that the content of luteolin in this herb is 0.7%. GC-MS was employed to analyzed chemical constituents of the essential oil from the flower of C. thalictrifolis. More than 60 peaks were detected and 45 of them were identified by comparing their spectra with that of the standards in the database and literatures. ESI-MS/MS was used to analyze the n-butanol extract of Passiflora incarnate. Based on the information of pseudo molecular ions and fragment ions of the glycosides, four major flavone-C-glycosides have been detected and identified as 7-methoxyluteolin-6-C-β-D-glucopyranoside, vitexin, swertisin and orientin. The isoflavone compounds in theextracts of three samples of B. chinensis collected in Gansu, Sichuan and Hunan, and the extract of Iris tectorum collected in Sichuan were analyzed by using TOF-HRMS and IT-MS. From the extracts of these herbs, a new isoflavone, identified as 5’,5,6,7-tetrahydroxy-3’4’-dimethoxyl isoflavon, and 7 known ones have been identified by analyzing the fragmentation patterns and their molecular formulas given by HRMS and the tandem mass spectrometry acquired by IT-MS. Chapter 4 elucidated the isolation and identification of a new triterpene saponin, androsacin (1), along with five known compounds (2-6) were isolated from the whole plants of Androsace integra (Maxim.) Hand.-Mazz., an herb used in traditional Chinese and Tibetan medicine. The chemical structure of the new compound was established as 3β-O-{β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-[O-β-D-glucopyranosyl-(1→2)]-α-L-arabinopyranosyl}-16α-hydroxy-13β,28-epoxy-olean-30-al by analyzing its MS, 1D- and 2D-NMR spectra. Compound 2 was cytotoxic toward HepG2 cancer cell with the GI50 value of 1.65 μg/mL. Chapter 5 described the biogenic pesticide activity screening of 68 traditional Chinese and Tibetan medicine extractions. The intention of this study is to explore bioactive natural compounds from these traditional medicinal herbs for biogenic insecticides use. Based on Syngenta’s bioassay, 14 extractions of these traditional medicines showed pesticide activities, and some of them had multi-activities on antibacterial and insecticidal. Chapter 6 is a review on the chemical and bioactivity research progress of Notopterygium incisum and N. forbesii.