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21.
利用mRNA差异显示技术(differential display)从草木樨状黄芪耐甲硫氨酸变异系中分离到一差异cDNA片段,命名为tm03(360bp)。mRNA杂交结果显示,该片段只在变异苗中表达,初步确定其与甲硫氨酸代谢相关。测序后在Genebank搜寻,未发现有同源序列。进一步分析表明,该cDNA克隆可编码完整的蛋白。在该基因片段两端分别合成含HindⅡ和BamH Ⅰ酶切位点的引物,用PCR扩增后亚克隆到pRSET A表达载体,转化宿主菌JMl09(DE3),经IPTG诱导表达了N′端含6个组氨酸的蛋白质,分子量约为14kD,为进一步研究该蛋白的结构和生物学功能奠定基础。  相似文献   
22.
牡丹花水提液对氧自由基的清除作用   总被引:9,自引:0,他引:9  
牡丹花水提液加入O 2和·OH的产生及检测系统中,能显著降低介导的氮兰四唑(NBT)的光化学还原和·OH作用下的水杨酸羟基化作用.这提示牡丹花水提液具有显著的清除氧自由基的活性,红色牡丹花水提液清除氧自由基的效能高于浅色花.  相似文献   
23.
白芍中丹皮酚、芍药苷和苯甲酸的反相薄层色谱分析   总被引:14,自引:0,他引:14  
建立了对白芍中丹皮酚、芍药苷和苯甲酸同时进行反相薄层色谱分析的新方法。以RP-C18F254S高效反相薄层板,选择了合适的溶剂体系:四氢呋喃/水46/54(0.1%的四丁基溴化铵),展距仅4.5cm,薄层扫描分析三者。结果准确,重现性好。  相似文献   
24.
芍药属牡丹组基于形态学证据的系统发育关系分析   总被引:5,自引:4,他引:1  
对芍药属牡丹组Paeonia L.sect.Moutan DC.(全部野生种)40个居群进行了基于形态学证据的系统学分析,试图建立组内种间的系统发育关系。利用PAUP (4.0)计算机程序分别构建了建立在25个形态学性状基础上的所有研究类群的距离树(UPGMA、NJ)和最大简约树(MP)。所得树的拓扑结构基本一致,差异只发生在距离树和简约树之间,在由形态和细胞学关系都很近的5个种(牡丹P.suffruticosa、矮牡丹P.jishanensis、卵叶牡丹P.qiui、紫斑牡丹P.rockii和凤丹P.o  相似文献   
25.
对柴达木盆地的西伯利亚白刺和唐古特白刺不同部位中氨基酸含量作了分析比较 ,并进行了营养评价。白刺中富含蛋白质 ,含有 18种氨基酸 ,其中有人体必需的 8种氨基酸 ,白刺果汁中的必需氨基酸含量远高于沙棘果汁。两种白刺的蛋白质和各氨基酸在各部位中含量分布相似 ,但因种的差异 ,第一限制性氨基酸稍有差别。  相似文献   
26.
Pn, Pg; Pn, Pg > Cy ; Pn, Cy and Pn, Cy > Pg groups. Each group consequently specified significant features among CIELAB color notation and petal pigmentation, being adequate to characterize tree peony flowers as similar between Zhongyuan and Daikon Island cultivars, thus the cultivars of the two areas are suggested to be related to one another. Received 25 April 2000/ Accepted in revised form 21 December 2000  相似文献   
27.
The purpose of this study was to analyze the phenolic profiles of seeds from fifteen Paeonia ostii cultivated populations in China and identify their relationship with antioxidant activities and associated environmental factors. Thirteen individual phenolic compounds were quantitatively determined by HPLC, and (+)‐catechin was the most abundant phenolic compound in the seeds. Correlation analysis showed that phenolics were the most effective antioxidant compound class by evaluating DPPH, ABTS, and hydroxyl radical scavenging activities as well as ferric reducing antioxidant power. Latitude and annual rainfall had significant effects on the contents of many phenolic compounds, and elevation was only significantly correlated with gallic acid content. Within fifteen P. ostii cultivated populations, the seeds of Tongling population exhibited the highest phenolic contents and strongest antioxidant activities. These results suggest that Tongling population has a relatively high utilization value and a potential for sources of natural antioxidants.  相似文献   
28.
The taxonomical history of the woody group(peonies) in the genus Paeonia is reviewed in the present paper. The group is endemic to China, but Paeonia suffruticosa is commonly cultivated throughout the north temperate region and has long been known as “the King of Flowers” in China. However, the taxonomy of the group had been neglected before the 1990' s. Since 1990, a number of new species and subspecies have been published. With the support from the National Geographic Society, the senior author of the present paper and his coworkers have made expeditions to all parts of the distribution area of the group, visited all the type localities and sampled a total of 64 populations. Based on the character analysis and examination of the type specimens or photos, each taxon is reviewed with its name checked nomenclaturally, and finally the taxonomy of the whole group is revised. As a result, eight species, three of which each contains two subspecies, are recognized. They are Paeonia suffruticosa Andrews subsp. suffruticosa and subsp. yinpingmudan D. Y. Hong, K. Y. Pan et Z. W. Xie, P. jishanensis T. Hong et W. Z. Zhao, P. qiui Y. L. Pei et D. Y. Hong, P. ostii T. Hong et J. X. Zhang, P. rockii (S. G. Haw et L. A. Lauener )T. Hong et J. J. Li subsp. rockii and subsp. taibaishanica D. Y. Hong, P. decomposita Hand.-Mazz. Subsp. decomposita and subsp. rotundiloba D. Y. Hong, P. delavayi Franeh. and P. ludlowii (Stern et Taylor)D. Y. Hong. P. baokangensis Z. L. Dai et T. Hong and P. yananensis T. Hong et M. R. Li are considered as hybrids between P. rockii and P. qiui and between P. rockii and P. jishanensis respectively. In addition, the reduction of a number of names recently published to synonyms is explained.  相似文献   
29.
30.
Paeonia suffruticosa Andrews subsp. spontanea (Rehder) S. G. Haw et L. A. Lauener ( =P. spontanea = P. jishanensis) has been considered as the wild form of widely cultivated P. suffruticosa. However, the subspecies differs from the cultivated one in shape, division and indumentum of leaves and reproductive biology. As a result of extensive field work, a form with two individuals in Yinping Shan, Caohu, Anhui, and Songxian, Henan, are found to be extremely similar to P. suffruticosa, but apparently different from P. jishanensis. The form is considered to be the wild one of P. suffruticosa and described as new: P. suffruticosa subsp, yinpingmudan Hong, K. Y. Pan et Z. W. Xie.  相似文献   
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