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1.
Two new spirostane‐steroidal saponins, bletilnoside A ( 1 ) and bletilnoside B ( 2 ), together with five known compounds, 3 – 7 , were isolated from the roots of Bletilla striata (Thunb .) Reichb . F. The structures of the new compounds were determined based on their 1D‐ and 2D‐NMR spectral data. The isolated compounds 1 – 7 were tested for cytotoxicity against four human tumor cells (A549, SK‐OV‐3, SK‐MEL‐2, and HCT15) in vitro using a sulforhodamin B bioassay, and compounds 1, 2 , and 5 showed significant cytotoxicities against all tested tumor cell lines with IC50 values ranging from 3.98±0.16 to 12.10±0.40 μM .  相似文献   
2.
阿拉善马先蒿(Pedicularis alaschania maxim)系玄参科马先蒿属植物,民间可代替夏枯草入药,主治淋巴结核、淋巴腺炎、高血压和甲状腺肿大等疾病。其化学成分研究尚未见报道。我们从马先蒿中分离得到2个单萜环烯醚甙P1和P2。P2经质谱(FAB MS)、核磁共振谱(~1H和~(13)C NMR)和红外光谱等数据与文献对照确定为桃叶珊瑚甙(aucubin)。P1为一新化合物。本文报道它们的分离与鉴定。  相似文献   
3.
马先蒿属植物苯丙素甙成分研究(Ⅰ)   总被引:1,自引:0,他引:1  
近年来,由苯丙素和糖组成的苯丙素甙由于具有药理活性而受到人们的重视[1~4].本文报道从穗花马先蒿(Pedicularis spicata)中分得的2个新苯丙素甙,马先蒿甙G(1)和H(2).  相似文献   
4.
微波消解/ICP-MS法测定不同地点三种马先蒿16种元素   总被引:1,自引:0,他引:1  
利用微波消解/ICP-MS法对三种马先蒿中16种元素进行了含量测定,该方法的加样回收率在95%~102%之间,相对标准偏差在1.24%~2.18%之间,具有较高的准确度和精确度。结果表明不同种马先蒿各元素的含量均有所不同,而且不同种马先蒿中各元素与海拔有不同的线性关系。实验结果为马先蒿的药效性和药理、毒理提供理论依据。  相似文献   
5.
A new iridoid glycoside 1 and a new iridoid 2 were isolated from the whole plant ofPedicularis kansuensis f. albiflora. Their structures were elucidated by spectroscopic methods.  相似文献   
6.
Three novel bibenzyl derivatives, blestritins A–C ( 1 – 3 ), along with 18 known constituents, were isolated from the tubers of Bletilla striata (Orchidaceae), a traditional Chinese medicine used for the treatment of tuberculosis and haemorrhage of the stomach and lungs. Their structures were identified on the basis of spectroscopic analyses.  相似文献   
7.
Lung cancer continues to be the world’s leading cause of cancer death and the treatment of non-small cell lung cancer (NSCLC) has attracted much attention. The tubers of Bletilla striata are regarded as “an excellent medicine for lung diseases” and as the first choice to treat several lung diseases. In this study, seventeen phenanthrene derivatives, including two new compounds (1 and 2), were isolated from the tubers of B. striata. Most compounds showed cytotoxicity against A549 cells. An EdU proliferation assay, a cell cycle assay, a wound healing assay, a transwell migration assay, a flow cytometry assay, and a western blot assay were performed to further investigate the effect of compound 1 on A549 cells. The results showed that compound 1 inhibited cell proliferation and migration and promoted cell apoptosis in A549 cells. The mechanisms might correlate with the regulation of the Akt, MEK/ERK, and Bcl-2/Bax signaling pathways. These results suggested that the phenanthrenes of B. striata might be important and effective substances in the treatment of NSCLC.  相似文献   
8.
As a representative medicinal plant in the Orchidaceae, Bletilla striata plays a variety of pharmacological roles in the clinic. However, the emergence of counterfeit species is affecting the basic medicinal materials source identification process, for which Bletilla ochracea and Oreorchis foliosa of the Orchidaceae are two representative species. For this study, 13 representative B. striata samples, three B. ochracea samples and three O. foliosa samples were selected for the systematic determination of polysaccharide yields and monosaccharide composition, and further detection of secondary metabolites by HPLC–MS. The results revealed that there was a significant difference in the yields of polysaccharides between B. striata and B. ochracea (p = 0.006). Although the polysaccharides of both species were composed of glucose and mannose, the molar ratio of the two monosaccharides was different, suggesting that the structures of the polysaccharides were different. The metabolomics results showed that there were no differences in the types of metabolites between B. striata and B. ochracea; however, there were differences in the contents of these metabolites. Although there was no significant difference in the polysaccharide yields of B. striata and O. foliosa (p = 0.074) and the monosaccharide composition was the same (glucose and mannose), many different metabolites were screened out between them: six compounds such as C36H34O11 existed only in B. striata, while substance C39H54O22 was unique to O. foliosa. Therefore, based on the analysis of the polysaccharide content and monosaccharide composition, combined with phase metabolomics research, a preliminary distinction between B. striata, B. ochracea and O. foliosa was achieved.  相似文献   
9.
报道了白芨沸水浸取液的三维荧光光谱和紫外吸收光谱。在三维荧光光谱图中出现3个荧光峰,分别位于λex/λem=227/299 nm,271/299 nm和258/ 389 nm。其中前2个荧光峰具有相同的发射波长,是由同一种荧光组分产生的,后1个荧光峰是由另外一种荧光组分产生的。三维荧光光谱具有特征性,可以用于白芨的定性鉴别。两种荧光组分的发射波长相距90 nm,可以不经分离而分别测量。在稀溶液条件下,两种组分的荧光强度与浓度之间都存在良好的线性关系,据此可以对两种组分进行定量分析。在pH 1.5~12.5范围内改变溶液的pH值时,两种组分的荧光强度有明显改变,表明两种组分的分子结构中存在可以离解的质子。  相似文献   
10.
Bletilla striata (Thunb.) Reichb. f. (Orchidaceae), also known as Bai‐ji, is a traditional Chinese herb that is widely used in Asia to treat hematemesis, hemoptysis, traumatic bleeding and other similar disorders. Most studies have focused on the pharmacological activities of polysaccharide extracts from B. striata. Our previous studies found that the nonpolysaccharide fraction from B. striata extract also has a hemostatic effect; however, the active constituents responsible for this pharmacological action are unclear. Thus, the metabolic profiles of the nonpolysaccharide fraction were investigated in Sprague–Dawley rats and intestinal bacteria models using ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. Mass data were acquired by the MSE method. Eight components including five prototypes and three metabolites were identified in rat biofluids after oral administration of the nonpolysaccharide fraction. The parent compounds underwent various metabolic processes, including hydrolysis, deglucosylation, glycosylation and sulfate conjugation. The results not only reveal the possible metabolic pathway, but also indicate the potential pharmacological components. Further mechanistic studies using nonpolysaccharide compounds of the B. striata extract are required to obtain potential candidate compounds.  相似文献   
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