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41.
菠萝香藤的倍半萜成分   总被引:6,自引:0,他引:6  
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42.
Summary The effect of age, pH of the culture medium, pre-treatment of tissues, enzymes sources and enzymatic adaptability of phycophages fed with a monospecific diet were analyzed on the protoplast yields of the red seaweed Solieria filiformis (Kützing) Gabrielson. New apices from fast growing plants showed the highest protoplast yields. The protoplast yield decreased when the pH of the culture medium increased from 6.0 to 9.0. Crude extracts from the abalone Haliotis coccinea canariensis Nordsieck, fed with Solieria filiformis thalli for three months in combination with cellulysin, released the highest number of viable cells and protoplasts. Yields ranged from 1.0 to 8.5 x 106 protoplasts per gram of fresh weight.Abbreviations AAP abalone acetone powder - Bis-Tris Bis(2hydroxyethyl)imino-tris(hydroxymethyl)methane - CMC carboxymethyl cellulose - EDTA ethylenediaminetetraacetic acid - EGTA ethylene glycol-bis(ß-aminoethyl ether) NNNN-tetraacetic acid - FDA fluorescein diacetate - FW fresh weight - Hepes N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid - Tris Tris(hydroxymethyl)aminomethane  相似文献   
43.
Cladistic analyses were conducted using morphological and ITS sequence data to examine phylogenetic relationships within the Schisandraceae. The most parsimonious trees obtained from the morphological data consistently show a dichotomy, with clades corresponding with the two currently accepted genera, Kadsura and Schisandra . In the ITS trees S. propinqua consistently groups with the Kadsura clade, and the position of S. glabra is uncertain. The trees resulting from the analysis of combined data are polytomous, due to the variable positions of K. scandens, K. coccinea and S. propinqua . The monophyletic status of Kadsura subgen. Kadsura sect. Kadsura and Schisandra subgen. Pleiostema are strongly supported, although the monophyly of other supraspecific taxa is unclear. Further studies are required before an unambiguous phylogeny is achieved for the family.  相似文献   
44.
BACKGROUND AND AIMS: It had previously been assumed that Maxillaria spp. produce no nectar. However, nectar has recently been observed in Maxillaria coccinea (Jacq.) L.O. Williams ex Hodge amongst other species. Furthermore, it is speculated that M. coccinea may be pollinated by hummingbirds. The aim of this paper is to investigate these claims further. METHODS: Light microscopy, histochemistry, scanning and transmission electron microscopy. KEY RESULTS: This is the first detailed account of nectar secretion in Maxillaria Ruiz & Pav. A 'faucet and sink' arrangement occurs in M. coccinea. Here, the nectary is represented by a small protuberance upon the ventral surface of the column and nectar collects in a semi-saccate reservoir formed by the fusion of the labellum and the base of the column-foot. The nectary comprises a single-layered epidermis and three or four layers of small subepidermal cells. Beneath these occur several layers of larger parenchyma cells. Epidermal cells lack ectodesmata and have a thin, permeable, reticulate cuticle with associated swellings that coincide with the middle lamella between adjoining epidermal cells. Nectar is thought to pass both along the apoplast and symplast and eventually through the stretched and distended cuticle. The secretory cells are collenchymatous, nucleated and have numerous pits with plasmodesmata, mitochondria, rough ER and plastids with many plastoglobuli but few lamellae. Subsecretory cells have fewer plastids than secretory cells. Nectary cells also contain large intravacuolar protein bodies. The floral morphology of M. coccinea is considered in relation to ornithophily and its nectary compared with a similar protuberance found in the entomophilous species M. parviflora (Poepp. & Endl.) Garay. CONCLUSIONS: Flowers of M. coccinea produce copious amounts of nectar and, despite the absence of field data, their morphology and the exact configuration of their parts argue strongly in favour of ornithophily.  相似文献   
45.
中泰南五味子( Kadsura ananosma Kerr )为五味子科( Schisandraceae)南五味子属( Kadsura Kaempf. ex Juss.)攀缘植物[1]14,其根、藤茎、果实是珍贵的傣药,具有收敛固涩、益气生津、补肾宁心的作用。对中泰南五味子化学成分的研究结果表明:中泰南五味子体内含有较多的木脂素类和三萜类成分,其中20多个成分为其特有成分,这些成分具有抗氧化、抗HIV病毒等药理活性[2-5]。中泰南五味子果实具有果大、肉多、酸甜可口等特点,还可作为野生水果食用,但目前对中泰南五味子果实的相关研究尚未见报道;相关志书[1]15,[6]234对其果实的基本描述也不完整,甚至空缺。为此,作者对野生中泰南五味子果实的形态特征进行观察,并对其营养成分进行分析,以期完善中泰南五味子果实的基础研究数据,为其深入开发和利用提供依据。  相似文献   
46.
The chloroplast mat-K region and rpL16 intron region were sequenced for 14 species of Schisandraceae, representing both genera Kadsura Kaempf. ex Juss. and Schisandra Michx, to discuss the phylogeny of this family. Analyses were performed both in separate and combined sequence data sets (including the rbc-L sequence), with Illicium angustispealum A. C. Smith as the out-group. The results showed that the Schisandraceae are monophyletic. In all the analyses, Schisandra propinqua var. chinensis Oliva and Schisandra plena A. C. Smith were nested within Kadsura, which implies that the genera Kadsura and Schisandra are closely related. They might have originated from a common ancestor, but then evolved via different routes. The result inferred from the combined data showed a greater resolution within Schisandra than those from the two separate data sets. High bootstrap values supported the monophyly of most subgenera according to Law's system (1996). A combination of morphological, anatomical, and chemical analyses indicates that S. chinensis and S. rubriflora may be the primitive taxa in Schisandra.  相似文献   
47.
矮生龙船花(IxoracoccineaL.)的带节茎段在MS 2,4D2.0mg/L培养基上产生大量的愈伤组织;在MS 6BA1.0mg/L NAA0.2mg/L培养基上芽的增殖系数达413,并产生少量的愈伤组织;在MS NAA0.2~2.0mg/L培养基上只产生芽而无愈伤组织形成。愈伤组织在MS 6BA0.5mg/L NAA0.5mg/L培养基上产生大量的不定芽,丛生芽在MS 6BA0.5mg/L NAA0.5mg/L培养基上生长较快并产生较多分枝,将分枝节下或切成段后在MS 6BA0.5mg/L NAA0.5mg/L培养基上能迅速生长并产生新的分枝。试管内小苗在1/2MS NAA0.5mg/L培养基上的生根壮苗效果较好。矮生龙船花试管苗成活率为935%。  相似文献   
48.
1. Saproxylic beetles (Coleoptera) have particular requirements for dead wood. Little is known about their larval development, especially within intermediate and late stages of dead wood decay. 2. We studied the natural foraging behaviour of three saproxylic beetles with morphologically similar (i.e. convergent) larvae and similar habitat requirements –Cucujus cinnaberinus Scopoli (Cucujidae), Pyrochroa coccinea L., and Schizotus pectinicornis L. (Pyrochroidae) – examining dietary components using visual gut content analysis. 3. There were few significant differences in diet among the study species, but there were significant differences for the different dietary components in individual species. Guts of all three species included more plant and fungal material than animal. We also observed that with increasing body size larvae foraged significantly less on fungal material. We observed significant differences among species and selection with respect to body size during the overwintering period. Larvae swallowed more animal and less fungal material with increasing body size. 4. The study species seem to be opportunistic foragers, varying their foraging capability according to seasonality and age. They probably generally foraged woody material infested by filamentous fungi (i.e. xylomycetophagy), swallowing other material that is in their way while foraging, including animal parts and small arthropods. 5. We found that morphologically similar larvae do not differ much in their foraging behaviour even when sharing the same habitat. Larval size seems to be a useful predictor for foraging behaviour of saproxylic beetles within the same guild. The study species are probably occasional predators with less ability to forage on other animals than previously suggested.  相似文献   
49.
为提高黑老虎(Kadsura coccinea)资源的综合利用率,采用广泛靶向代谢组学技术鉴定并分析了根、茎、叶代谢组分差异及高度富集成分。结果表明,在根、茎和叶中分别鉴定出642、650和619个代谢物,以酚酸、脂质、类黄酮和有机酸为主;叶与根、茎与根的共有成分分别为566和650个,显著差异成分有442和393个,主要为酚酸、类黄酮和脂质,差异代谢物在苯丙烷生物合成、黄酮与黄酮醇生物合成通路中显著富集。代谢物总丰度和次生代谢物丰度均表现为叶>根>茎,叶中酚酸、类黄酮和脂质及茎中酚酸积累量显著高于根,而氨基酸及其衍生物、萜类、木脂素、香豆素、生物碱的丰度在根中显著上调。因此,黑老虎根、茎、叶有大量共有成分,叶和茎中酚酸、叶中类黄酮和脂质高度富集,含有新绿原酸、绿原酸、槲皮素等多个丰度较高且具有重要生物活性化合物,具有较高利用价值。  相似文献   
50.
 The structure of floral nectaries of Crataegus coccinea and C. crus-galli was examined using light and scanning electron microscopy. The radial length of the floral nectary, measured from longitudinal sections of flowers, was 30% larger in C. crus-galli than in C. coccinea. For both Crataegus species the glandular tissue thickness was similar – approx. 400 μm. Also, the number of stomata per mm2 of nectary surface in C. crus-galli was much higher (by 43%) than for C. coccinea. Stomata were situated in deep hollows. For both taxa the period of nectar secretion was 4 days. The mean quantity of total sugar in nectar per 10 flowers of C. crus-galli and C. coccinea was 3.87 mg and 0.33 mg, respectively. Received August 28, 2002; accepted December 17, 2002 Published online: June 2, 2003  相似文献   
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