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81.
五味子科植物花形态及其系统学意义   总被引:9,自引:2,他引:7  
用光镜和扫描电镜观察了五味子科Schisandraceae23种、6变种和1变型的91份花粉的形态。其中5 、4变种和1变型的花粉形态为首次报道。该科花粉为单花粉,异极,辐射对称,扁球形至超扁球形,其萌发沟的排列格局在被子植物中是独一无二的。若按萌发沟的数目划分,该科花粉可分为3沟型和6沟型两个类型。外壁为网状纹饰,网眼的大小和网脊的宽度与花的形态有一定相关性。研究结果不支持Praglowski对  相似文献   
82.
湖北新记录属植物永瓣藤种群现状及其保护   总被引:1,自引:0,他引:1  
永瓣藤(MonimopetalumchinenseRehd.)为湖北省种子植物区系新记录属、种,是中国二级保护植物。通山县分布的永瓣藤为次生杉、竹、阔混交林内的伴生成分,群落生活型谱以常绿高位芽植物为主,种群空间分布格局为集群型。其生态适应为明显的偏酸性和一定的耐荫性。永瓣藤种群虽规模小,但具明显的增长型特征,有发展潜力。文中对永瓣藤生物多样性保护提出了具体的建议  相似文献   
83.
目的:分离具有抗肿瘤作用与抗菌作用的内生放线菌,并对其进行分子鉴定和系统发育分析.方法:从皱叶南蛇藤中分离内生放线菌,通过滤纸片法和SRB法对其进行抗菌活性和抗肿瘤活性筛选,然后利用菌株形态特征、培养特征、生理生化特性和16S rRNA基因序列分析对活性菌株进行鉴定结果:从皱叶南蛇藤中分离到10株内生放线菌,其中内生放线菌LCB369具有较好的抗菌活性和抗肿瘤活性,该菌对5种致病菌和肝癌细胞株HepG2均有抑制作用.经分子分类学分析鉴定,该菌与Streptomyces microflavus 在同一个分支上,同源性为99%.结论:皱叶南蛇藤内生菌LCB369具有明显抗菌和抗肿瘤作用,经鉴定为链霉菌Streptomyces microflavus.  相似文献   
84.
Two new hetisine-type C20-diterpenoid alkaloids named spiraqine (1) and 6-hydroxylspiraqine (2), and four known alkaloids, namely spiredine (3), spiradine A (4), spiradine B (5), and spirasine Ⅴ/Ⅵ (6),were isolated from Spiraea japonica L. f. var. fortunei (Planchon) Rehd. The structures of the alkaloids were elucidated using nuclear magnetic resonance analysis (1H-NMR, 13C-NMR, DEPT, HMQC, and HMBC) and mass spectrometry data.  相似文献   
85.
Schizandra chinensis has been known to have five predominant tastes: salty, sweet, sour, astringent, and bitter. It has also been shown to have various effects on the cardiovascular system, gastrointestinal system, anti-inflammatory, central nervous system, endocrine system, and stress protect. However, its anti-cancer activity on colon carcinoma HCT-116 cells has not been yet been examined. Thus, in this study, we attempted to isolate a compound from Schisandra chinensis that induced apoptosis in HCT-116 cells. An active compound was found and identified to be Gomisin A. It displayed apoptotic activity through caspase-7 cleavage in colon carcinoma HCT-116 cells. In addition, we further assessed the effects of this compound using long-term survival clonogenic assay with HCT116 cells.  相似文献   
86.
Introduction – Direct analysis in real time (DART) ion source is a powerful ionising technique for the quick and easy detection of various organic molecules without any sample preparation steps, but the lack of quantitation capacity limits its extensive use in the field of phytochemical analysis. Objective – To improvise a new system which utilize DART‐MS as a hyphenated detector for quantitation. Methodology – A total extract of Schisandra chinensis fruit was analyzed on a TLC plate and three major lignan compounds were quantitated by three different methods of UV densitometry, TLC‐DART‐MS and HPLC‐UV to compare the efficiency of each method. To introduce the TLC plate into the DART ion source at a constant velocity, a syringe pump was employed. The DART‐MS total ion current chromatogram was recorded for the entire TLC plate. The concentration of each lignan compound was calculated from the calibration curve established with standard compound. Results – Gomisin A, gomisin N and schisandrin were well separated on a silica‐coated TLC plate and the specific ion current chromatograms were successfully acquired from the TLC‐DART‐MS system. The TLC‐DART‐MS system for the quantitation of natural products showed better linearity and specificity than TLC densitometry, and consumed less time and solvent than conventional HPLC method. Conclusion – A hyphenated system for the quantitation of phytochemicals from crude herbal drugs was successfully established. This system was shown to have a powerful analytical capacity for the prompt and efficient quantitation of natural products from crude drugs. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
87.
Separate benzocyclooctadiene lignans were isolated from the berries of Schisandra chinensis in milligram quantities on analytical reverse phase (RP) HPLC by an automated repeat-injection method and shown to have anti-proliferative activity against human colorectal cancer cells. Structures of the compounds were determined by a combination of NMR and mass spectrometry. Stereospecific NMR assignments for gomisin-N and deoxyschisandrin, gave more complete and accurate data than previously reported, based on 600 MHz 2D HSQC, DQF-COSY and HMBC data. Comparison of coupling constants and HMBC crosspeak intensities with calculated and X-ray crystal structures confirmed their stereochemistry and conformation. Analysis of structure–activity relationships revealed the importance of key structural determinants. The S-biphenyl configuration of gomisin N, the most active lignan, correlated with increased anti-proliferative activity, while the presence of a hydroxyl group at the C7 position reduced or abolished this activity. Increased activity was also observed when a methylenedioxy group was present between C12 and C13. The percent yield of the most active compounds relative to the starting plant materials was 0.0156% for deoxyschisandrin and 0.0173% for gomisin N. The results of these studies indicate that automated repeat-injection method of analytical HPLC may provide a superior alternative to the standard semi-preparative HPLC techniques for separation of complex mixtures.  相似文献   
88.
不同氮素形态比例对五味子幼苗生长特性的影响   总被引:2,自引:0,他引:2  
以2年生五味子苗木为试验材料,在田间条件下,施以铵态氮(NH4+-N)和硝态氮(NO3--N)不同比例,分析了叶片可溶性蛋白、叶绿素含量、根系及茎叶中全氮含量、生物量等季节的动态变化规律,探讨了不同氮素形态比例对五味子苗木生长的影响。结果表明,五味子苗木在不同生长时期对不同氮素形态的吸收和利用存在明显差异,NH4+-N和NO3--N对五味子幼苗生长有显著的联合效应。在五味子生长前期,五味子主要以吸收和同化NH4+-N为主,并以铵态氮和硝态氮比例为75∶25时地上部生物量积累较多;而在五味子生长的中后期,五味子主要以NO3--N吸收和同化为主,并以铵态氮和硝态氮比例为25∶75时地上部生物量积累较多。  相似文献   
89.
Schisandra chinensis has been regarded as a useful material in the preventive or treatment of several human diseases. The study of the Schisandra chinensis’ molecular identity has been prioritized because it has been found to regulate cellular responses. Here, we examined the effects from various extracts of Schisandra chinensis to monitor the relative intracellular calcium increase in human neutrophils. We identified an active molecule and structural configuration of a new active compound (α-iso-cubebene), based on the discovery of a cubebene backbone using NMR, MS, and CD spectral data. In terms of its functional aspect, we observed that α-iso-cubebene strongly stimulated CXCL8 production in human neutrophils. Also, α-iso-cubebene-induced CXCL8 production was almost completely inhibited by the calcium chelator, EGTA, thus highlighting the role of calcium signaling in the process. Taken together, our results demonstrate that α-iso-cubebene is a novel natural compound which stimulates intracellular calcium signaling and CXCL8 production. As a result, α-iso-cubebene should be useful for the development of an immune-modulating agent.  相似文献   
90.
Two new 7,8‐secolignans, marphenols A and B ( 1 and 2 , resp.), together with a known related derivative, 7,8‐secoholostylone B ( 3 ), were isolated from the stems of Schisandra wilsoniana. The structures of 1 and 2 were elucidated by spectroscopic methods, including extensive 1D‐ and 2D‐NMR techniques. The anti‐HIV‐1 activities of 1 – 3 were evaluated. Compound 1 inhibited HIV‐1IIIB‐induced syncytia formation with an EC50 value of 0.55 μg ml?1. It reduced p24 antigen expression in acutely HIV‐1IIIB‐infected C8166 cells and primary isolate HIV‐1TC‐2‐infected peripheral blood mononuclear cells (PBMCs), with EC50 values of 3.34 and 0.52 μg ml?1, respectively. It showed no effects on the HIV‐1IIIB replication in chronically infected H9 cells as well as fusion inhibition.  相似文献   
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