Phenolic compounds from the leaves and stem bark of Pseudospondias microcarpa (A. Rich.) Engl. (Anacardiaceae)

Phytochemical study of the leaves and the stem bark of Pseudospondias microcarpa (A. Rich.) Engl. afforded eight phenolic compounds: scopoletin (1), ferulic acid (2), isovitexin (3), rhoifolin (4), quercetin 3-O-α-L-rhamnopyranoside (5), justicialoside A (6), granduloside A (7) and pithecellobiumol B (8). The structures of the isolated compounds were elucidated by spectroscopic means including 1D and 2D NMR and MS, and by comparison with previously reported data. This is the first report on the isolation of these compounds from the genus Pseudospondias. The chemotaxonomic significance of the isolated compounds within the family Anacardiaceae is discussed.     

Enantiomeric separation of racemic 1-benzyl-N-methyltetrahydroisoquinolines on chiral columns and chiral purity determinations of the O-methylated metabolites in plant cell cultures by HPLC-CD on-line coupling in combination with HPLC-MS

Effective enantiomeric separations of 1-benzyl-N-methyltetrahydroisoquinolines were achieved using commercially available Chiralcel OD-H and OJ-H columns. Online LC-CD analysis allowed for the establishment of a correlation between the absolute configuration of the separated enantiomers and their characteristic CD transitions. LC-MS combined with LC-CD analysis permitted chiral purity determinations of O-methylated metabolites of nine phenolic 1-benzyl-N-methyltetrahydroisoquinolines in cell cultures of Corydalis, Macleaya, and Nandina species.     

中国科学家完成博落回全基因组测序并解析苄基异奎宁类生物碱途径

博落回(Macleaya cordata)是罂粟属的一种传统中药, 因其富含具有抗菌功能的血根碱(SAN)和白屈菜红碱(CHE), 可以作为牲畜抗菌生长促进剂的安全来源植物。中国科学家以博落回为材料, 利用从头测序手段测定了首个罂粟属植物全基因组序列。研究人员通过组织特异性代谢谱及表达谱分析鉴定了博落回中16个参与血根碱和白屈菜红碱合成的候选基因, 并结合同源克隆及饲喂实验对其中的14个基因进行了体外功能验证。上述研究为进一步探索博落回中血根碱等苄基异奎宁类生物碱(BIAs)合成、调控及后续合成奠定了基础, 也为解析罂粟属其它植物的代谢途径提供了有力工具。     

Differential diversifications of South American and Eastern Asian disjunct genera Bocconia and Macleaya (Papaveraceae)

Bocconia (10 species) and Macleaya (2 species) are two disjunct genera between South America and eastern Asia (EAS) in the Papaveraceae offering an opportunity to compare its biogeographic history with that of the well‐known disjunction between EAS and eastern North American (ENA). Our phylogenetic analyses of the chloroplast matK and rbcL gene sequences of Ranunculales including two species of Macleaya and six species of Bocconia supported the monophyly of Bocconia, Macleaya, and Chelidonioideae to which Bocconia and Macleaya belong. Nucleotide sequences of matK, rbcL, and nrDNA ITS supported the sister relationship of Bocconia and Macleaya. Biogeographic analyses of Chelidonioideae using S‐DIVA (statistical dispersal vicariance analysis) and DEC (dispersal extinction cladogenesis) methods inferred Eurasia as the most likely ancestral area of Bocconia and Macleaya and suggested no extinction events in either Bocconia or Macleaya. This agrees with the “Out‐of‐Asia” pattern of the EAS‐ENA disjunction. Molecular dating of Ranunculales with fossil‐based calibrations showed that Bocconia and Macleaya diverged in the late Eocene and early Oligocene, which is much earlier than most EAS‐ENA disjunct taxa. The disjunction may have formed via long distance dispersal or boreotropical connections via the North Atlantic and Bering land bridges. Both Bocconia and Macleaya diversified in the late mid‐Miocene, but Bocconia has apparently experienced a greater diversification probably aided by the evolution of the bird dispersal syndrome in fruit and seed after migration to South America. The greater diversification of Bocconia is also evidenced by the diverse leaf morphology and growth habit in response to colonization in various local habitats in South America.     

两种亚热带榕属乔木植冠损伤后的位置依赖性枝发生

三峡库区需要大量植株用于三峡工程所涉及的诸多建设(如铁路、公路、建筑)之后的植被恢复和绿化.由于具有优美树冠和耐瘠薄土壤的能力,榕(Ficus microcarpa L.)和黄桷树(Fvirens Ait.var.sublanceolata(Miq.)Cornor) 在三峡库区作为绿化和行道树木大量栽植.在三峡库区,这两种树种苗木的培育主要通过切枝扦插的方式进行.大量切枝损伤植株植冠并且使叶组织数量减少,对植株生长有很大影响.植株生长与植株的枝发生格局有很大关系,为明确植冠损伤对植株生长的可能影响,对榕和黄桷树植冠损伤后的枝发生进行了研究.实验发现,切枝造成的植冠损伤对榕和黄桷树植株侧枝上的枝发生没有影响,不同损伤强度之间和不同损伤发生时间之间都不存在明显的差异.但是,植冠损伤后,榕和黄桷树植株主茎上的枝发生是位置依赖性的.植冠损伤不影响榕和黄桷树植株损伤处理后新生主茎段和具侧枝主茎段上的枝发生,却促进了损伤处理后裸露主茎段上的枝发生,并且裸露主茎段上枝发生的数量和密度随植冠损伤强度的升高而增大.此外,实验结果表明,秋季植冠损伤植株裸露主茎段上的枝发生要高于春季植冠损伤植株裸露主茎段上的枝发生;在榕和黄桷树的枝发生中,仅有裸露主茎段上增强的枝发生会促进植冠损伤植株对叶组织的生物量投资并有利于受损植株的恢复和生长.     

不同采收期紫玉盘中抗癌活性的初步研究

对不同采收期紫玉盘植物提取物,采用SRB法观察其对人口腔上皮癌细胞株(KB)生长的影响进行抗癌活性检测,结果发现抗癌活性物质随采收期的不同其活性具有显著差异,10月份采收的紫玉盘植物提取物体外抗癌活性最强。     

星盾炱属一新种

星盾炱属新种紫玉盘星盾炱Asterina uvariae-microcarpae寄生在番荔枝科植物紫玉盘Uvaria microcarpa (Annonaceae)的叶上。新种有拉丁文和英文描述,附了显微结构图。模式标本保存在广东省微生物研究所标本室(HMIGD)。     

不同水分条件对人参榕生长和生理的影响

以3年生人参榕(Ficus microcarpa)为试材,采用盆栽调控水分的方法,研究5种不同的水分处理(基质最大含水量的90%～100%,70%～80%,50%～60%,30% ～ 40%和10%～20%)对人参榕生长和生理的影响,为栽培生产提供理论依据.结果表明:随着浇水量的减少,人参榕的株高、冠幅、块根增量均显著下降(P＜0.05);人参榕叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)活性显著增高(P＜0.05),细胞膜相对透性显著增强,脯氨酸和丙二醛(MDA)含量也显著增加;叶片净光合速率(Pn)和蒸腾速率(Tr)呈随浇水量的减少而显著降低;但叶片水分利用效率(WUE)呈显著增加趋势;各处理的叶片初始荧光(F0)和最大光量子效率(Fv/Fm)差异不显著.在各处理中,70%～80%的最大基质含水量的处理,其人参榕叶片的细胞膜相对透性最低,保护酶活性最弱,脯氨酸和丙二醛含量最低,净光合速率高,从而导致了人参榕具有生长最快、株高、冠幅和最大块根直径增量最大的特点.可见,70%～80%的最大基质含水量为是人参榕种植效果最好的水分管理模式.