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鹿药属植物叶表皮特征及其系统学意义 总被引:7,自引:1,他引:6
采用光学显微镜和扫描电镜对鹿药属12种植物的叶表皮进行了观察,首次报道了12种鹿药属(Sm ilaci-na)植物叶表皮的微形态特征。结果表明:气孔器普遍存在于叶的下表皮,少数种的上表皮也有分布,均为不规则形。叶表皮细胞形状为多边形或不规则形,垂周壁式样可区分为近平直、浅波状和波状。在扫描电镜下,叶表皮气孔器外拱盖内缘为近平滑、浅波状或波状;角质膜条纹状,有的条纹隆起,有的条纹上附有颗粒和晶簇。气孔器的分布、气孔器外拱盖内缘形态以及角质膜等特征对该属部分种的区分具有一定的参考价值。 相似文献
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Atropurosides A-G (1-7), seven new steroidal saponins, which possess new polyhydroxylated aglycones, were isolated from the rhizomes of Smilacina atropurpurea (Convallariaceae), together with a known saponin, dioscin (8). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. Antifungal testing of the eight compounds indicated that atropurosides B (2) and F (6) were fungicidal against Candida albicans, Candida glabrata, Cryptococcus neoformans, and Aspergillus fumigatus with minimum fungicidal concentrations (MFCs) < or = 20 microg/ml, while dioscin (8) was selectively active against C. albicans and C. glabrata (MFC < or = 5.0 microg/ml). Furthermore, the antifungal saponins 2, 6, and 8 were evaluated for their in vitro cytotoxicities in a panel of human cancer cell lines (SK-MEL, KB, BT-549, SK-OV-3, and HepG2) and non-cancerous Vero cells. All showed moderate cytotoxicities. It appears that the antifungal activity of these steroidal saponins correlates with their cytotoxicity against mammalian cells. 相似文献
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Light harvesting and utilization by chloroplasts located near the adaxial vs the abaxial surface of sun and shade leaves were examined by fluorometry in two herbaceous perennials that differed in their anatomy and leaf inclination. Leaves of Thermopsis montana had well-developed palisade and spongy mesophyll whereas the photosynthetic tissue of Smilacina stellata consisted of spongy mesophyll only. Leaf orientation depended upon the irradiance during leaf development. When grown under low-light levels, leaves of S. stellata and T. montana were nearly horizontal, whereas under high-light levels, S. stellata leaves and T. montana leaves were inclined 600 and 300, respectively. Leaf inclination increased the amount of light that was intercepted by the lower leaf surfaces and affected the photosynthetic properties of the chloroplasts located near the abaxial leaf surface. The slowest rates of quinone pool reduction and reoxidation were found in chloroplasts located near the adaxial leaf surface of T. montana plants grown under high light, indicating large quinone pools in these chloroplasts. Chloroplasts near the abaxial surface of low-light leaves had lower light utilization capacities as shown by photochemical quenching measurements. The amount of photosystem II (PSII) down regulation, measured from each leaf surface, was also found to be influenced by irradiance and leaf inclination. The greatest difference between down regulation monitored from the adaxial vs abaxial surfaces was found in plants with horizontal leaves. Different energy dissipation mechanisms may be employed by the two species. Values for down regulation in S. stellata were 2–3 times higher than those in T. montana, while the portion of the PSII population which was found to be QB nonreducing was 4–6 times lower in high light S. stellata leaves than in T. montana. All values of Stern-Volmer type nonphotochemical quenching (NPQ) from S. stellata leaves were similar when quenching analysis was performed at actinic irradiances that were higher than the irradiance to which the leaf surface was exposed during growth. In contrast, with T. montana, NPQ values from the abaxial leaf surface were up to 45% higher than those from the adaxial leaf surface regardless of growth conditions. The observed differences in chloroplast properties between species and between the adaxial and abaxial leaf surfaces may depend upon a complex interaction among light, leaf anatomy and leaf inclination. 相似文献
4.
Fifteen species in six genera of the family Liliaceae were karyomorphologically studied. They share the complex chromocenter type of the resting nuclei and the interstitial type of the prophase chromosomes in somatic cells except that Clintonia udensis Trautv. et Mey is of the densely diffuse type and gradient type respectively. Their karyotype formulas are listed as follows: Clintonia udensis Trautv. et Mey, 2n= 14=8m+4sm+2st (2SAT), belongs to 2A type; Smilacina henryi (Baker) Wang et Tang, 2n=36=12m+16sm+6st+2t (2SAT), 2C type; Smilacina fusca Wall., 2n = 36= 14m (2SAT)
+ 12sm+ 10st(2SAT), 2B type; Smilacinata tsienensis (Franch.) Wang et Tang, 2n= 36=22m +2sm+ 2st(2SAT), 2C type; Smilacina atropurpurea ( Franch.) Wang et Tang, 2n=36=18m+6sm(2SAT) +12st, 2C type: Polygonatum kingianum Coll, et Hesml., 2n=30= 12m(2SAT) +6sm+ lst+2t, 2C type; Polygonatum cirrhifolium (Wall.) Royal, 2n=30= 10m+4sm+ 12st+4t, 3C type; Polygonatum curvistylum Hua, 2n=78=24m (2SAT)+ 14sm (6SAT)+40st, 3C type; Polygonatum cathcartii Baker, 2n = 32 = 12m + 6sm + 10st+ 2t + 2Bs, 2C type; Lilium henricii Franch., 2n = 24 = 2m(2SAT) + 2sm + 10st+ 10t, 3A type; Lilium bakerianum Coll. et Hesml. var. rubrum Stearn, 2n=24=4m ( 2SAT) +10st+ 10t (2SAT), 3A type; Nomocharis bilouensis Liang, 2n= 24= 2m (2SAT) +2sm+ 12st+ 8t, 3A type; Nomocharis pardanthina Franch., 2n= 24=4m (2SAT)+12st (2SAT)+ 8t, 3A type; Nomocharis sauluensis Balf. f., 2n=24=4m(2SAT) +10st (2SAT) + 10t, 3B type; Notholirion campanulatum Cotton et Stearn 2n = 24 = 2m (2SAT) + 2sm + 14st(2SAT ) + 6t, 3A type. 相似文献
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6.
Penetration of UV-B radiation in foliage: evidence that the epidermis behaves as a non-uniform filter 总被引:9,自引:4,他引:5
In some plants, particularly herbaceous species, a considerable proportion of incident ultraviolet-B radiation (UV-B, 280-320 nm) penetrates into the leaf mesophyll where it is potentially damaging to nucleic acids and the photosyn-thetic machinery. We used optical techniques to look at the spatial variation in UV-B penetration through the epidermis of foliage of two herbaceous species (Chenopodium album and Smilacina stellata)and a conifer (Picea pun-gens). Measurements of UV-B penetration in intact foliage with a fibre-optic microprobe revealed that 300 nm radiation reached 161±36μm (mean±SD) into leaves of C. album, 154±40μm in S. stellata and 17±2μm in P. pungens, with epidermal transmittance being 39±14%, 55±19% and 0%, respectively. A thin polymer film was developed which fluoresced blue when irradiated by UV-B. Fresh epidermal leaf peels were placed over the film and irradiated with UV-B, and microscopic examination of the film from below allowed us to determine the spatial pattern of UV-B penetration through the epidermis. In herbaceous species, film fluorescence below cell walls, but not epidermal and guard cell protoplasts indicated that UV-B transmittance was much greater through anticlinal cell wall regions than protoplasts. Ultraviolet-B transmittance through large areas of epidermal cells could be induced by plasmolysis. Epidermal transmittance was also relatively high through stomal pores (and what appear to be nuclei in Smilacina), but relatively low through stomatal guard cells. Results from the fluorescing film technique were substantiated by direct measurements of UV-B transmittance through epidermal peels with a fibre-optic microprobe run paradermally along the bottom or inner side of irradiated peels. In Smilacina, we estimate that UV-B epidermal transmittance was up to 90% through anticlinal cell wall regions, but <10% through protoplast areas. In contrast to herbaceous species, we did not detect any UV-B transmittance through the epidermis of P. pungens with either the fluorescing film or the fibre-optic microprobe technique. The epidermis appears to be a much more spatially uniform UV-B filter in conifers than in these herbaceous species. 相似文献
7.
云南高黎贡山管花鹿药茎叶营养成分分析 总被引:5,自引:0,他引:5
测定了云南高黎贡山管花鹿药茎叶的营养成分 ,并与常见蔬菜及一些粮谷类食物进行了比较 ,结果显示 :管花鹿药茎叶含多种营养成分 ,干品蛋白质含量高达 4 4 92 %、氨基酸含量为 2 6 4 %、含有多种人体必需的常微量元素 ,矿质元素含量呈十分典型的高钾低钠特点 :钾含量高达 395 0mg/kg ,而钠含量仅为 0 14mg/kg ,Fe、Mn、Zn等元素含量也较高 ,具有较高的营养价值和良好的营养保健作用 相似文献
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Four new steroidal saponins, smilacinoside A (1), B (2), C (3), and D (4), together with three known saponins, funkioside D (5), aspidistrin (6) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-beta-d-glucopyranosyl-(1-->2)-beta-d-glucopyranosyl-(1-->4)-beta-d-galactopyranoside (7) were isolated from the dried tender aerial parts of Smilacina atropurpurea (Franch.) Wang et Tang. The structures of new compounds were elucidated as diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->2)-O-beta-d-galactopyranoside (1), diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->3)-[6-O-palmitoxyl]-O-beta-d-galactopyranoside (2), 26-O-beta-d-glucopyranosyl-(25R)-furost-5-en-3beta,22xi,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)}-beta-d-galactopyranoside (3) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-galactopyranoside (4) on the basis of chemical methods and detailed spectroscopic analysis, including 1D and 2D NMR techniques and single-crystal X-ray diffraction, respectively. Six of these compounds and MeOH extract were tested for their in vitro cytotoxicity toward K562 human tumor cells by an improved MTT method. Smilacinoside A, funkioside D and aspidistrin exhibited significant in vitro cytotoxicity against K562 with IC(50) values of 1.09, 2.93 and 0.47microg/mL, respectively. 相似文献
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In the present paper the karyotypes of Smilacina tatsienensis (Franch.) Wang
et Tang and Ophiopogon japonicus (L. f.) Ker.- Gawl. in Sichuan were analysed. The karyotypes of the two species are reported for the first time. The results are shown as follows.
Smilacina tatsienensis (Franch.) Wang et Tang is a dipoiid. Its karyotype formula is
2n=2x=36=16m+10sm+10st(4SAT) (Plate 1: Fig. 1, 3). The karyotype is bimodal with ten
large and eight small chromosome pairs and the length ratio of the tenth pair to the eleventh
being 1.33. The length ratio of the largest chromosome and the smallest one is 4.33. Ophiopogon japonicus (L.f.) Ker.-Gawl. is a mixoploid, with diploid, triploid and tetraploid cells in a single plant. The karyotype formula of the diploid is 2n=2x=36=18m (4SAT)+18sm(Plate 1: Fig. 2, 4). The species is of a bimodal karyotype with eight large and ten small chromosome pairs and the length ratio to the eighth pair and the ninth being 1.10.There are nine metacentric pairs (two pairs of sat-chromosomes) and nine submetacentric pairs. 相似文献
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