Identification and characterization of proanthocyanidins of 16 members of the Rhododendron genus (Ericaceae) by tandem LC–MS

The proanthocyanidins of the leaves of 16 taxa of the Rhododendron genus (Ericaceae) [Rhododendron ‘Catawbiense Grandiflorum’, Rhododendron ‘Cunningham's White’, Rhododendron smirnowii Trautv., Rhododendron calophytum Franch., Rhododendron dichroanthum ssp. scyphocalyx (Balf. f. & Forrest ) Cowan, Rhododendron micranthum Turcz., Rhododendron praevernum Hutch., Rhododendron ungernii Trautv., Rhododendron kaempferi Planch., Rhododendron degronianum ssp. heptamerum var. hondoense ( Nakai ) H. Hara, Rhododendron fortunei Lindl., Rhododendron ponticum L., Rhododendron galactinum Balf. f. ex Tagg., Rhododendron oreotrephes W. W. Sm., Rhododendron brachycarpum ssp. brachycarpum D. Don ex G. Don, and Rhododendron insigne Hemsl. & E. H. Wilson ] were investigated qualitatively by liquid chromatography–mass spectrometry in series. Twenty‐nine dimeric proanthocyanidins based on (epi)catechin and (epi)gallocatechin were detected and characterized on the basis of their unique fragmentation pattern in the negative ion mode tandem mass spectrometry spectra. All of them were extracted for the first time from these sources, and ten of them were not reported previously in nature. The position of the galloyl residue was assigned on the basis of the retro‐Diels–Alder fragmentation and the dehydrated retro‐Diels–Alder fragmentation; it resulted from the loss of gallic acid as a neutral loss in the negative ion mode. Furthermore, four caffeoylquinic acids, six p‐coumaroylquinic acids, epigallocatechin, gallocatechin, catechin, epicatechin, epigallocatechin gallate, catechin gallate, epicatechin gallate, gallocatechin gallate, two quercetin‐O‐hexosides, quercetin‐O‐galloyl‐hexoside, quercetin‐O‐pentoside, quercetin‐O‐rhamnoside, quercetin‐O‐pentoside‐O‐hexoside, quercetin‐O‐rhamnoside‐O‐hexoside, quercetin‐O‐feruloyl‐hexoside, quercetin‐O‐(p‐hydroxy)benzoyl‐hexoside, taxifolin‐O‐pentoside, myricetin‐O‐rhamnoside, two myricetin‐O‐pentosides, three myricetin‐O‐hexosides, and two myricetin‐O‐galloyl‐hexosides were detected and shown to possess characteristic tandem mass spectrometry spectra and were tentatively assigned on the basis of their retention time. Copyright © 2012 John Wiley & Sons, Ltd.     

长白山野杜鹃花精油化学成分的研究

文中采用GC/MS法,研究了具有显著祛除青春痘效果的长白山野杜鹃花精油的化学成分.鉴定出47种化合物,测定了各化合物的相对含量,其中主要成分为对伞花烃(23.47%)、异土荆芥油素(18.88%)、桧烯(9.88%)和α 松油烯(7.61%).在杜鹃花精油中首次检出的土荆芥油素和异土荆芥油素则可能是其药效的主要成分.     

走胆草高效液相指纹图谱的研究

目的:建立抗肝炎药走胆草药材的HPLC指纹图谱.方法:反相高效液相色谱法,流动相为甲醇-水(含0.1%磷酸),梯度洗脱,流速为1.0ml·min-1,检测波长为270nm,柱温为30℃.结果:精密度、重复性、稳定性试验中共有峰的峰面积小于5%、保留时间的RSD值均小于3%;不同产地的走胆草的相似度大于0.90.结论:该方法简便、可靠,可作为走胆草药材的质量标准.     

Chemical fingerprint analysis of Fritillaria delavayi Franch. by high-performance liquid chromatography

Bulbus of Fritillaria delavayi Franch. is the most commonly used antitussive and apophlegmatic in China and commonly prepared by water decoction. In this study, a novel and reliable method of high-performance liquid chromatography (HPLC) was developed both for quantitative analysis of 10 bioactive compounds (uracil, cytidine, inosine, uridine, guanosine, thymidine, adenosine, hypoxanthine, adenine and 2-deoxyadenosine) and chemical fingerprint analysis of F. delavayi Franch. In quantitative analysis, 10 compounds showed good regressions (R(2) > 0.9982) within test ranges and the recovery of the method was in the range of 96.33-104.51%. In the fingerprint analysis, 11 characteristic peaks were selected to evaluate the similarities of F. delavayi Franch. samples, and the HPLC chromatograms of 16 samples from different regions of China showed similar patterns. The results from the experiment demonstrated that the combinations of the quantitative and chromatographic fingerprint analysis offer an efficient way to evaluate the quality consistency of F. delavayi Franch.     

云锦杜鹃气孔行为对水分的响应

以盆栽5年生云锦杜鹃苗木为材料，分对照、轻度、中度、重度4组，研究了土壤水分胁迫下气孔导度的变化，结果表明：随着水分胁迫的加重，净光合速率、蒸腾速率和气孔导度降低，云锦杜鹃气孔导度日变化曲线由双峰型逐渐转变为峰值很小的单峰型，水分胁迫的影响差异显著；经逐步多元回归得到了气孔导度日变化的回归方程．     

6种杜鹃花属(Rhododendron)植物叶片结构的研究

利用光学显微镜和扫描电子显微镜观察了6种杜鹃属植物的叶片结构,结果表明,它们具有共同形态结构特征：典型的异面叶,上表皮由2～3层细胞组成,内大外小或内、外等大,有较厚的角质膜,无气孔器分布;下表皮均由1层细胞组成,排列紧密;栅栏组织由2层以上长柱形细胞组成,排列紧密;海绵组织细胞较短,排列较疏松,细胞间隙较大;均有表皮附属物。但是在各种间也存在结构差异,如叶片的厚度,气孔大小、气孔形态、气孔指数以及分布类型,表皮附属物的类型以及中脉维管束的类型等的结构特征,这些结构特征差异既是抗寒抗旱性的表现形式,也在分类学上为种问鉴别提供了可靠依据。     

杜鹃属植物的引种适应性研究

庐山植物园自1982年始开展杜鹃属植物引种驯化研究，共引种杜鹃花近300种(品种)。笔归纳了该园20余年来在杜鹃花引种栽培中所取得的经验，并通过对杜鹃在栽种地生长发育的观察，分析探讨了杜鹃属植物在庐山地区的适应性。结果表明：(1)原产中国日本森林植物亚区的杜鹃生长好干中国喜马拉雅森林植物亚区，尤其是长江中下游中高山地区引种的杜鹃生长极佳；(2)引自亚热带湿润季风气候带的杜鹃生长好于南亚热带半湿润气候带(滇南及滇西南)；(3)广生态幅的物种适应性好于狭生态幅的；(4)向温暖湿润气候演化的温带和亚热带林下类群的杜鹃生长良好，而向旱、寒生环境演化的高山类群或热带附生类群的有鳞杜鹃在庐山适应性差；(5)总体来看适应性强弱表现依次为：落叶杜鹃亚属，马银花亚属，常绿杜鹃亚属，羊踯躅亚属，有鳞杜鹃亚属；(6)原产日本、北美地区的杜鹃在庐山生长适应性良好，久经栽培的种引种易于成功。     

Determination of Anthocyanins and Flavonols in Paeonia delavayi by High-Performance Liquid Chromatography with Diode Array and Mass Spectrometric Detection

The colors of the leaves in Paeonia delavayi may be pure green, green-red, or dark red according to their habitat. The goal of this study was to compare the type and the total concentrations of anthocyanins and flavonols in red and green P. delavayi. The constituents and concentration of anthocyanins and flavonols were identified and determined by high-performance liquid chromatography with diode array detection and mass spectrometry. Cyanidin-3, 5-di-O-glucoside, cyanidin-3-O-glucoside, and peonidin-3-O-glucoside were first determined in red P. delavayi. There were no anthocyanins in green P. delavayi. Seven flavonols were identified in both red and green P. delavayi with differences in their concentrations. The concentrations of total anthocyanins and flavonoids were determined at 525 and 360?nm using the external standard method. The total anthocyanins in red P. delavayi were 152.24?mg/100?g in leaves and 78.92?mg/100?g in stems. The total flavonoids were 805.4?mg/100?g in leaves and 438.3?mg/100?g in stems, which were much higher than in green P. delavayi for both leaves and stems. This study reports composition and concentration differences in red and green P. delavayi based on ecological habitat.     

云南杜鹃属植物多样性的空间分布格局

目的：杜鹃属（Rhododendron）植物具有极高的欣赏价值,同时,也具有一定的经济价值。因此,对该属植物多样性空间分布格局的研究具有重要的现实和理论意义。方法：利用文献资料,采用相关分析的方法,探讨了不同地理梯度上云南杜鹃属植物多样性的分布格局。结果：在海拔梯度上,随海拔的升高,该属植物多样性呈先增加后下降的偏峰分布格局,符合“中间膨胀效应”理论;在度梯度上,物种丰富度随度的升高呈单调递增格局,这可能与该属植物的区系起源和生态特性有关;在经度梯度上,从东到西,物种丰富度呈单调递增趋势。结论：研究区域内杜鹃属植物的分布主要集中在高纬度、中高海拔（2500～4000m）左右的滇北地区。     

Evolution of stomatal and trichome density of the Quercus delavayi complex since the late Miocene

A fossil oak species,Quercus tenuipilosa Q.Hu et Z.K.Zhou,is reported from the upper Pliocene Ciying Formation in Kunming,Yunnan Province,southwestern China.The establishment of this species is based on detailed morphologic and cuticular investigations.The fossil leaves are elliptic,with serrate margins on the apical half.The primary venation is pinnate,and the major secondary venation is craspedodromous.The tertiary veins are opposite or alternate-opposite percurrent with two branches.The stomata are anomocytic,occurring only on the abaxial epidermis.The trichome bases are unicellular or multicellular.The new fossil species shows the closest affinity with theextant Q.delavayi and the late Miocene Q.praedelavayi Y.W.Xing et Z.K.Zhou from the Xiaolongtan Formation of the Yunnan Province.All three species share similar leaf morphology,but differ with respect to trichome base and stomatal densities.Q.tenuipilosa.Q.praedelavayi,and Q.delavayi can be considered to constitute the Q.delavayi complex.Since the late Miocene,a gradual reduction in trichome base density has occurred in this complex.This trend is the opposite of that of precipitation,indicating that increased trichome density is not an adaptation to dry environments.The stomatal density(SD)of the Q.delavayi complex was the highest during the late Miocene,declined in the late Pliocene,and then increased during the present epoch.These values show an inverse relationship with atmospheric CO_2 concentrations,suggesting that the SD of the Q.delavayi complex may be a useful proxy for reconstruction of paleo-CO_2 concentrations.