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21.
根据对单叶黄荆(Vitex simplicifolia)模式标本的研究,结合在其模式产地的野外调查,发现单叶黄荆与黄荆(V.negundo)并无本质区别,不宜作为独立的种,但其叶片为单叶而且比较稳定,将其降级并组合为黄荆的变种。  相似文献   
22.
野生荆条籽中挥发油成分的研究   总被引:1,自引:0,他引:1  
用水蒸气蒸馏法从荆条中提取挥发油,用气相色谱-质谱联用技术对挥发油成分进行分离和结构鉴定。从荆条籽的挥发油中鉴定出了51个组分,用气相色谱面积归一法确定了各个组分的相对百分含量,其挥发油的主要组成是β-榄香烯(27.98%),芳樟醇(12.39%),贝壳杉烯(12.00%),δ-榄香烯(10.54%),乙酯异冰片脂(8.98%)等。  相似文献   
23.
为研究牡荆叶指纹图谱与抗氧化活性的谱-效关系,该研究首先建立了18批牡荆叶的高效液相色谱-电化学检测法(HPLC-ECD)指纹图谱,对不同来源牡荆叶药材进行聚类分析,鉴定主要酚类化合物且测定其含量,分析牡荆叶的总酚和总黄酮含量,并采用DPPH自由基清除法、ABTS自由基清除法、氧自由基吸收能力法及铁离子还原能力法考察其体外抗氧化活性,通过皮尔逊相关分析、灰度关联分析及偏最小二乘回归分析法研究牡荆叶的谱-效关系。结果表明:(1)牡荆叶的指纹图谱标定21个共有峰,共指认出10个峰,其含量顺序为绿原酸>异荭草苷>木犀草苷>异牡荆素>异绿原酸A>异绿原酸C>原儿茶酸>荭草苷>异绿原酸B>新绿原酸;不同产地样品间相似性较高,相似度结果为0.816~0.983。(2)系统聚类分析显示,样品含量对分类有一定影响,不同来源样品被分为3类,其中南北方样品存在一定差异。(3)牡荆叶中总酚和总黄酮的含量分别为15.82~61.83 mg·g-1和27.85~157.65 mg·g-1,样品均具不同程度的抗氧化活...  相似文献   
24.
In young individuals of the obligate myrmecophytic liana Vitex thyrsiflora, several species of ants and other arthropods compete for resources offered by the plant. In mature individuals, the only inhabitant is the ant species Tetraponera tessmanni, which is completely restricted to Vitex lianas as its sole host. Established colonies of this ant provide effective defense against herbivores. The association between V. thyrsiflora and T. tessmanni is unusual in two respects. First, the climbing life form is rare among myrmecophytes. Secondly, it is surprising that a pseudomyrmecine should be the obligate associate of a liana. Pseudomyrmecine plant‐ants often prune vegetation contacting their host plant. This behavior functions in part to protect against invasion of the host by ecologically dominant ants. In contrast, T. tessmanni does not prune and is associated with a plant whose success, and thus that of its resident ant colony, depends on contacts with many other plants. Several traits of V. thyrsiflora and T. tessmanni combine to make the colonization of host plants by potential competitors very difficult. These include behavioral and morphological filters restricting entrance into the plant and exploitation of the resources it can supply; plant anatomical organization that enables T. tessmanni workers to carry out all activities, except leaf patrolling, within a single, branched private nesting space within which all food resources offered by the plant are produced; and polygyny, permitting the colony to monopolize a large, rapidly growing and long‐lived territory.  相似文献   
25.
鄱阳湖沙地沙漠化过程中单叶蔓荆群落结构和功能特征   总被引:2,自引:0,他引:2  
在鄱阳湖沙地不同沙化程度区开展单叶蔓荆群落组成及其物种多样性变化调查.结果表明:随着沙漠化程度的增加,多年生草本和灌木逐渐减少,物种多样性减少,至重度沙化时,沙地植被明显退化,群落结构趋于简单和不均匀;在不同程度沙化区和植被恢复演替过程中,物种组成结构具有递进性和渐变性;在沙山治理过程中,可进行单叶蔓荆和禾本科植物配植...  相似文献   
26.
研究了培养基、植物生长调节素以及接种量对Vitex glabrata R.Br.悬浮培养细胞的生长情况以及对20-羟基蜕皮激素形成的作用。当细胞在添加有2.0mg/L BAP (6-苯甲酸嘌呤)和1.0mg/L 2,4-D的Gamborg's B5培养基中培养时细胞生长和20-羟基蜕皮激素的形成达到了最高水平。当接种量为20%PCV(积压细胞体积)时观察到了20-羟基蜕皮激素的最高产量,大约是1.1mg/(L·d)。实验数据也表明当接种量增加到20%PCV时,产量提高了7倍。  相似文献   
27.
山牡荆的化学成分研究   总被引:1,自引:0,他引:1  
研究山牡荆根茎的化学成分。山牡荆根茎经80%丙酮提取,采用硅胶和凝胶进行分离纯化,通过波谱分析进行结构鉴定。从山牡荆中分离得到5个化合物,分别鉴定为:β-谷甾醇(1)、牡荆葡基黄酮(2)、20-羟基蜕皮素-20,22-单丙酮化合物(3)、3,5-O-双咖啡酰基奎宁酸(4)和胡萝卜甾醇(5),这5个化合物均为首次从该植物中分离得到。  相似文献   
28.
本变种小叶边缘具缘毛,聚伞花序单生叶腋,有时成对簇,通常3-4次二歧分枝,花序梗短于少为长于或等长于叶柄,花冠管较短,长6-7mm,内面近中部具一环白色长毛,核果较小.长6-7mm,直径5-6mm。  相似文献   
29.
This study describes in vitro shoot induction and plant regeneration from a mature apical meristem and nodal explants of the endangered medicinal shrub Vitex agnus-castus. Multiple shoots were induced directly from the axis of nodal and apical meristem explants on Murashige and Skoog (MS) medium containing 3% sucrose and different concentrations (1.0, 1.5, 2.0, and 2.5 mg/l) of 6-benzyl aminopurine (BAP) in combination with Kinetin (Kin) and α-naphthalene acetic acid (NAA), both at 0.1 mg/l. BAP and Kinetin were used as supplements to MS basal medium, either individually or in combination with auxins. The optimal concentration of BAP for inducing bud break was found to be 2.0 mg/l when Kinetin was at 0.1 mg/l. Regeneration frequency was highest for both apical meristem and nodal explants (94.5% and 90.3%, respectively) when explants were cultured on MS medium supplemented with BAP (2.0 mg/l) and Kin (0.1 mg/l). A maximum of 7.7 ± 0.4 and 6.7 ± 0.2 shoots were obtained per explant for apical meristem and nodal explants, respectively. Regenerated shoots, transferred to MS medium supplemented with either 1.0 or 1.5 mg/l BAP combined with 0.1 mg/l GA3, showed maximum elongation of 6.7 ± 0.4 and 6.0 ± 1.3 cm in apical meristem and nodal explants, respectively. In vitro regenerated shoots transferred to half-strength MS medium supplemented with 0.1 mg/l IBA induced 90.4% of the shoots to form roots after 30–35 d of culture. Up to 80% of the regenerated shoots were successfully established in soil in the greenhouse.  相似文献   
30.
Iridoids and ecdysteroids are found in some genera of the family Verbenaceae. In such cases, they are used as chemotaxonomic markers for the difficult task of taxonomic identification by using morphological characteristics of plants belonging to this family. The present work describes the distribution of ecdysteroids in plants from the genus Vitex from a review of previous work on seventeen Vitex species. In addition, (13)C-NMR data of the main ecdysteroids found in this genus are described. This study attempted to summarize previous research on ecdysteroids distribution in Vitex species with the addition of (13)C-NMR analysis to further refine the characterization of these compounds in the Verbenaceae family.  相似文献   
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