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1.
Chiisanoside is the main component of Acanthopanax sessiliflorus leaves. Simultaneous administration of chiisanoside resulted in a decrease in the plasma TG level and increase of undigested TG in the intestinal lumen after oil gavage to mice. This suggests that chiisanoside has the potential to prevent obesity as a lipase inhibitor which suppresses fat absorption in vivo.  相似文献   
2.
刺五加传粉生物学研究   总被引:13,自引:0,他引:13  
本文报道刺五加Eleutherococcus seticosus(Rupr.et Maxim.)Maxim的花朵酬物、访花者类别、访花 者在花序上的访花行为、访花频率及传粉效果。主要结果如下:(1)每朵雄花可提供的报偿是58 000~ 81 000粒花粉,5.5~8.0 µl/d×2~4d花蜜。每朵雌花仅可提供4.0~8.0µl/d× 2~3 d花蜜,不能提 供花粉。每朵两性花可提供19 000~54 000粒花粉和7.0~10.0 µl/d× 2~6 d花蜜。(2)花粉提供者 (雄花和两性花)提供报偿的日期是开花后1~3天,花粉接受者(雌花和两性花在柱头外翻变白时)是 开花后5~7或7~9天,这进一步证实了剌五加雄蕊先熟。另外,花粉提供者提供花蜜的时间在一天中 是8:30至15:30,其高峰是9:00~15:00;花粉接受者提供花蜜的时间在一天中是10:30至16:30,其高 峰是11:00~16:00。这种时间差异可能是刺五加影响传粉者流向(从花粉提供者到花粉接受者)的关键 因素。(3)在刺五加花朵上记录到的访花昆虫有50余种,分别隶属于膜翅目、鳞翅目、鞘翅目、双翅目和 半翅目。在不同天气、不同生境、不同性别的植株记录到的访花频率及高峰时间不同:花粉提供者的 访花高峰早于花粉接受者的;雄株上的访花频率高于雌株的;两性株接受花粉时的访花频率高于提供花 粉时的;而天气越晴朗,刺五加地块(patch)越大,则访花频率越高;每日接受光照越早,访花高峰越早。 (4)从传粉效果看,刺五加种子的形成完全依赖于传粉昆虫的活动。其中,蜂类,如熊蜂、花蜂、切叶蜂、胡蜂和蜜蜂等是最有效的传粉者,其它昆虫如粉蝶、食蚜蝇、寄蝇和鳃角金龟等对传粉也有帮助。  相似文献   
3.
短柄五加大,小孢子发生和雌,雄配子体发育的研究   总被引:6,自引:2,他引:4  
王仲礼  田国伟 《植物研究》1998,18(2):177-183
短柄五加花药5枚,每个花药四个花粉囊。小孢子母细胞减数分裂时,胞质分裂为同时型,产生正四面体形的四分体。花药壁由表皮、药室内壁、中层和绒毡层四层细胞组成,其发育类型为双子叶型。腺质绒毡层,其细胞为二核。三细胞型花粉。子房5室,每室两个胚珠,上胚珠败育,下胚珠可育。下胚珠倒生,具单珠被,厚珠心。大孢子母细胞减数分裂形成线性排列的四个大孢子,雌配子体发育属蓼型。开花当天,花粉散开,雌配子体尚未成熟,处  相似文献   
4.
High frequency somatic embryogenesis of Eleutheorcoccus chiisanensis was achieved through suspension culture of embryogenic cells in hormone-free Murashige and Skoog liquid medium supplemented with 30 g sucrose l−1. Cotyledonary somatic embryos were germinated and converted into plantlets using 20 μM gibberellic acid which were then grown in a 10 l airlift bioreactor. HPLC analysis revealed the accumulation of eleutheroside B, E and E1 in the embryos and plantlets. Thus mass production of embryos and plantlets of E. chiisanensis can be achieved in liquid cultures and the biomass produced may become an alternative source of eleutherosides.  相似文献   
5.
Ling You X  Seon Yi J  Eui Choi Y 《Protoplasma》2006,227(2-4):105-112
Summary. Eleutherococcus senticosus zygotic embryos were pretreated with 1.0 M mannitol or sucrose for 3–24 h. This pretreatment resulted in a high frequency of somatic-embryo formation on hormone-free medium. All the somatic embryos developed directly and independently from single epidermal cells on the surface of zygotic embryos after plasmolyzing pretreatment. Scanning electron microscopic observation revealed that the epidermal cells of hypocotyls rapidly became irregular and showed a random orientation before somatic-embryo development commenced. At the same time, the epidermal cells in the untreated control remained regular. Callose concentration determined by fluorometric analysis increased sharply in E. senticosus zygotic embryos after plasmolyzing pretreatment but remained low in the untreated control. Aniline blue fluorescent staining of callose showed that the plasmolyzing pretreatment of zygotic embryos resulted in heavy accumulation of callose between the plasma membrane and cell walls. On the basis of these results, we suggest that plasmolyzing pretreatment of zygotic embryos induces the accumulation of callose, and the interruption of cell-to-cell communication imposed by this might stimulate the reprogramming of epidermal cells into embryogenically competent cells and finally induce somatic-embryo development from single cells. Correspondence and reprints: Division of Forest Resources, College of Forest Sciences, Kangwon National University, Chunchon 200-701, Republic of Korea.  相似文献   
6.
Ammonium to nitrate ratios of 0:30, 5:25, 10:20, 15:15, 20:10, 25:5, and 30:0 mM were tested to determine the optimal NH(4)(+) :NO(3)(-) ratio for improving biomass and bioactive compound production in Eleutherococcus koreanum Nakai adventitious roots using 3-L bulb-type bubble bioreactors. A high ammonium nitrogen ratio had a negative effect on root growth, and the highest fresh and dry weights were obtained when NH(4)(+):NO(3)(-) ratios were 5:25 and 10:20 (mM) after 5 weeks of culture. Although the total production of eleutherosides B and E was slightly higher at the 10:20 ratio than at the 5:25 ratio (NH(4)(+):NO(3)(-)), we proposed that the optimal NH(4)(+):NO(3)(-) ratio was 5:25 mM. This ratio achieved both the highest total production of five target bioactive compounds (eleutherosides B and E, chlorogenic acid, total phenolics, and flavonoids) and the highest root biomass. Furthermore, increasing NH(4)(+):NO(3)(-) ratios to 10:20 decreased pH in the medium, interrupted the absorption of essential minerals from the culture medium, and resulted in low biomass and increased relative oxidative stress levels, which were evaluated by determining 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Therefore, nitrate rather than ammonium nitrogen was more essential not for only biomass production but also for bioactive compound production in E. koreanum adventitious root cultures. The optimal nitrogen source ratio produced 5.63 g L(-1) of biomass and 24.41 mg of the five total bioactive compounds per gram of biomass (dry weight basis). The development of such in vitro culture technology will benefit the pilot-scale production of E. koreanum-based bioactive compounds for commercialization.  相似文献   
7.
短柄五加开花及传粉生物学研究   总被引:15,自引:0,他引:15  
本文对短柄五加(Eleutherococcusbrachypus)的花期物候、开花式样、访花昆虫种类、访花行为及访花频率进行了观察,对花粉活力、柱头可授性、花粉胚珠比以及传粉效果和繁育系统做了检测。初步结果表明,短柄五加以根茎进行无性繁殖,1个居群为1个无性系。虽自交亲和,但昆虫的访花活动可显著提高座果率。昆虫传粉主要在无性系内异花间进行,属于广义的自花传粉。传粉者为多种不同的昆虫,包括马蜂和胡蜂在内的蜂类、蝇类和甲虫。其花期物候、花粉活力、柱头可授期和蜜汁分泌期等特征使其能够适应环境,从而获得较高的座果率。平均座果率为65%,饱满种子率为45.5%。自然条件下未发现实生苗,广义的自花传粉导致的种子质量低下可能是其原因,也是限制短柄五加分布范围的重要因素。  相似文献   
8.
Eleutherococcus brachypus Harms. is a protandrous plant because the female gametophyte delays its maturation until the fifth day after anthesis and pollen shelling. On the fifth day after anthesis, about 57.69% of the embryo sacs matured and the rest degenerated or failed to develop. Fertilization began in the embryo sac on the fifth day. On the tenth day fertilization took place in 53.37 % of the total of embryo sacs. The stigma became receptible after 3 to 4 days of anthesis. It took 2 to 3 days from the germination of pollen grains on stigma to the fusion of male and female nuclei. The process of fertilization in E. brachypus is not different from most other angiosperms. It belonged to the type of premitotic syngamy. The observations and statistical analysis were made on the number feature of male and female nucleoli in the zygote. The result indicated that it took three days or so from the appearance of male nucleolus in the zygote to its fusion with the female nucleotus. Refering to the number of free nuclei of the endosperm, the fusion of male and female nucleoli in most of the zygotes occurred in the stage of 32 to 128 nuclei of the endosperm. Most zygotes con-tained a big nucleolus resulting from the fusion of male and female nucleolus and proceeding to mitosis. A few without fusion could also proceed to the mitotic stage. Features of multiple sperms entering the embryo sac or entering the egg cell and the degeneration of mature embryo sacs were observed as well. The sign of the termination of fertilization in angiosperms was discussed.  相似文献   
9.
Seeds of Eleutherococcus brachypus Harms were flat-kidney-shaped and their seed coats were only composed of one layer of cells. Embryos with abundant protein in their cells were just at the heart-shaped stage and were capped by sacs formed from degenerating endosperm cells when seeds shed from their maternal plants. A large amount of stored protein grains and lipids existed in endosperm cells but no polysaccharide grains were present either in endosperm cells or in embryo cells. Viable seeds were only 9.27% of the total. The plump seeds germinated in the cultivated field after 18~19 months and their germinating rate was 1.67%. Besides, the content of protein decreased gradually and a few polysaccharide grains were stored in embryo cells during the process. The afterripening process of seeds stratified at different temperatures ended after 6 months and the cytochemistry features of the seeds were that the content of protein decreased gradually and numerous polysaccharide grains had been stored in embryo cells at the late heart-shaped embryo stage and retained till the mature embryo stage. The structure, afterripening and cytochemistry of seeds were compared between Eleutherococcus brachypus and Eleutherococcus senticosus. The poor quality of the seeds, longer time of afterripening in a natural state and much lower germination rate of E. brachypus are considered to be important reasons for the endangerment of this species. Somemeasures are suggested for its conservation based on the above facts.  相似文献   
10.
The development status of gynoecia in Eleutherococcus senticosus flowers is different from that in ordinary plants. Female gametophytes of E. senticosus have not become mature until the 6th day after anthesis. On the 6th day, 82.25% of embryo sacs in female plants, and 67.25% of those in hermaphroditic plants become mature, while the rest are sterile, immature or degenerated with no fertilized embryo sacs observed. At the same time, all embryo sacs degenerated and flowers withered in male plants. On the 7th day, a few embryo sacs in female and hermaphroditic plants start being fertilized. Accompanying the differentiation of embryo sacs, styles of female and hermaphroditic flowers start to expand and their nectaries become mature gradually. After the 4th or 6th day of anthesis, stigmatic papillae become conspicious and stigmata become white and open. In the meantime, the stigmata become receptive and the nectaries get active or reactive. By the 9th or 10th day, 40~65 % of embryo sacs in female plants and 25~41% of those in hermaphroditic plants have been fertilized. The whole process of fertilization in E. senticosus was observed. About 2 or 3 days after pollination, the two sperm nuclei start to fuse with the egg and the secondary nucleus. The fertilization of E. senticosus belongs to the premitotic type of syngamy. The essential process of the fusion of male and female nuclei during syngamy may be generalized as follows: (1) the contacting of male nucleus with the female one; (2) the fusion of nuclear membranes between the male and female nuclei; (3) the despiralization of male spireme and the appearance of male nucleolus inside the fertilized female nucleus; (4) the dispersion of male chromatin and the mergence with the female chromatin, which is the sign of completion of the fusion of the two nuclei. In addition, degeneration types of mature embryo sacs were observed. And typical polyspermy and a series of cases in which extra sperms enter the em-bryo sac are recorded.  相似文献   
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