The effect of frugivory on postdispersal seed removal and germination in the pantropical forest tree Antiaris toxicaria Leschenault

The quality of seed treatment by frugivores has an effect on seed removal after dispersal, seed germination and tree recruitment. We provide information on postdispersal seed removal, germination and subsequent recruitment in tropical forest tree species Antiaris toxicaria in Ghana. We tested whether postdispersal seed removal and germination rates were differentially affected by the following seed treatments: seeds that were spat out by monkeys with all fruit pulp removed and spitting seeds with fruit pulp partially removed as observed in some birds and bats. We used seeds of intact ripened fruits as control. Frugivore seed treatment and distance from bole affected seed removal patterns, whereas intact seeds were significantly removed from all seed stations. The germination success was greater for seeds that were spat out by monkeys and poor for seeds with fruit pulp partially removed and intact fruits. More recruits were recorded at the edge of the adult A. toxicaria canopy radius. There was weak relationship (r² = 0.042) between the number of recruits and distance away from the adult tree. Results suggest that the subsequent recruitment in tropical forest tree species may be enhanced by some frugivore fruit‐handling behaviour where fruit pulp is removed from the seeds without destroying the seeds.     

见血封喉乳汁中具有细胞毒活性的强心苷

从见血封喉(Antiaris toxicaria (Pers.) Lesch.)乳汁分离得到4个强心苷类化合物,经波谱数据分析,分别鉴定为：毒毛旋花子爪哇糖苷(1)、铃兰毒苷(2)、毒毛旋花子阿洛糖苷(3)和glucostrophanthidin (4)。化合物4为首次从见血封喉中分离得到。细胞毒活性测定结果表明,化合物1~4对慢性髓原白血病细胞(K562)、人胃癌细胞(SGC-7901)和人肝癌细胞(SMMC-7721)的增殖均显示了较强的生长抑制活性。     

从见血封喉的分布看广东省热带与亚热带的界线划分

广东省的热带与亚热带的分界线按不同的划分标准,大致已有4条分界线。见血封喉(Antiaris toxicaria)是一个典型的热带种类,它在广东的分布北限,一直被认为是广东热带的最北界限。根据最近在广东发现的见血封喉4个新分布点,通过分析见血封喉的生态学特性和地理分布特征,同时参考热带界线划分的标准与原则,讨论并尝试重新界定广东省的热带与亚热带分界线。     

见血封喉树叶化学成分研究

从见血封喉(Antiaris toxicaria(Pers.)Lesch.)树叶中分离得到了6个化合物,经波谱数据分析,分别鉴定其结构为:(3S,5R,6S,7E,9R)-3,6-dihydroxy-5,6-dihydro-β-ionol(1)、(5R)-4,5-二氢布卢门醇A(2)、槲皮素-3-O-β-D-葡萄糖苷(3)、异鼠李素-3-O-β-D-芸香糖苷(4)、山柰甲黄素-3-O-β-D-葡萄糖苷(5)和环氧松柏醇(6),以上化合物均为首次从该种植物中分离得到.     

见血封喉种子中的强心苷类化合物及其细胞毒活性

从海南产见血封喉(Antiaris toxicaria (Pers.) Lesch.)种子的乙醇提取物中分离得到7个强心苷类化合物,通过波谱分析(NMR, MS, IR等),鉴定其结构分别为：杠柳苷元(1)、见血封喉阿洛糖苷(2)、见血封喉去氧阿洛糖苷(3)、毒毛旋花子苷元(4)、毒毛旋花子阿洛糖苷(5)、毒毛旋花子爪哇糖苷(6)和去葡萄糖桂竹香毒苷(7)。化合物7为首次从见血封喉种子中分离得到。细胞毒活性测试结果表明,化合物1~7均对慢性髓原白血病细胞(K562)、人胃癌细胞(SGC-7901)和人肝癌细胞(SMMC-7721)的增殖有较强的生长抑制活性。     

Possible Involvement of Reactive Oxygen Species Scavenging Enzymes in Desiccation Sensitivity of Antiaris toxicaria Seeds and Axes

The relationships among desiccation sensitivities of Antiaris toxicaria seeds and axes, changes in activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and dehydroascorbate reductase, (TBA)-reactive substance were studied. Desiccation tolerance of seeds and axes decreased with dehydration. Desiccation tolerance of axes was higher than that of seeds, and that of epicotyls was higher than radicles. Activities of SOD, CAT and DHAR of seeds increased during the initial phase of dehydration, and then decreased with further dehydration, whereas activities of APX and GR decreased with dehydration. These five enzyme activities of axes, however, increased during the initial phase of dehydration, and then decreased with further dehydration. The rate of superoxide radical production, and the contents of H2O2 and TBA-reactive products of seeds and axes gradually increased with dehydration. These results show that the A. toxicaria seed is a typical recalcitrant seed. Loss of desiccation tolerance in seeds and axes was correlated with activities of seeds and axes.     

三种药用植物内生菌的分离及其抗肿瘤活性菌株的筛选

对204株分离自长春花、海南粗榧和见血封喉的内生菌进行了抗肿瘤活性筛选。结果显示,有19株内生菌的发酵液至少对一种指示瘤株具有细胞毒活性,其中4株菌的发酵液对S180的抑制率较强,均在70%以上。研究表明菌株PA09006和PA09009发酵液中的抗肿瘤活性物质,具有一定的酸碱耐受性,并且对温度和紫外线具有一定的稳定性。     

见血封喉乳汁脂溶性成分及其抗氧化活性研究

首次采用气相色谱.质谱联用技术(GC-MS)对见血封喉(Antiaris toxicaria(Pers.)Lesch.)乳汁的脂溶性成分进行了分析,共鉴定了27个化学成分,占其总量的91.7%.用清除DPPH自由基能力的方法测定了见血封喉乳汁脂溶性部位的抗氧化活性,结果显示出一定的抗氧化活性,SC50值为500μg ml-1.     

箭毒木种子蛋白质样品制备及双向电泳改良方法

建立箭毒木（Antiaris toxicaria）种子总蛋白的提取方法,以及可以对其蛋白质组进行分析的双向电泳条件。通过各种条件的优化与组合,建立了以TCA-丙酮为基础的Tris—HCl提取法提取总蛋白,第1向电泳为固相pH梯度等电聚焦,第2向电泳为垂直平板SDS-PAGE的双向电泳体系。通过对样品制备、样品溶解、等电聚焦电泳、SDS-聚丙烯酰胺凝胶电泳以及染色方法等关键步骤进行分析,获得了满意的双向电泳图谱。在探索适合箭毒木种子蛋白质组学研究双向电泳方法中,比较了三氯乙酸-丙酮沉淀法、和Tris—HCl法,以及对双向电泳过程中的关键步骤的改良,认为Tris—HCl法为最适方法,所得图谱背景清晰,蛋白质信息量最大,为箭毒木属植物的差异蛋白质组学的后续研究打下了坚实的基础。