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1.
Extracellular ferricyanide reduction, NADH and ferrocyanide oxidation were investigated by spectrophotometrical method on photosynthetic freshwater plants ( Elodea canadensis Rich., Vallisneria spiralis L., Nitella flexilis L.) and heterotrophic tissues (roots of Triticum vulgare L., Hordeum vulgare L., Zea mays L., Pisum sativum L., Avena sativa L., Allium sativa L., Allium cepa L.). All species had ferricyanide reductase activity. The roots of land plants also carried out extracellular oxidation of NADH and ferrocyanide in contrast to leaves of the freshwater plants. External NADH stimulated ferricyanide reductase activity, but only with those objects that had external NADH oxidase activity. In all species ferricyanide decreased the membrane potential (MP), decreased the membrane resistance measured at a fixed current and inhibited K+ influx measured by flame photometry. The factors affecting ferricyanide reductase activity also influenced the inhibitory effect of ferricyanide on the MP and K+ transport. These results demonstrate a connection between transport, electrogenic and redox functions of the plasmalemma.  相似文献   

2.
The volatile constituents of the essential oils of 23 taxa belonging to the Apioideae subfamily were studied in detail. The investigated taxa were Pimpinella serbica (Vis.) Bentham & Hooker, Libanotis montana Cr., Cnidium silaifolium (Jacq.) Simk. ssp. orientale (Boiss.) Tutin, Bupleurum praealtum L., B. sibthorpianum S. S. var. diversifolium (Roch.) Hay, Aegopodium podagraria L., Torilis anthriscus (L.) Gmel., Orlaya grandiflora (L.) Hoffm., Laserpitium siler L., Laser trilobum (L.) Brokh., Chaerophyllum aureum L., C. hirsutum L., C. temulum L., Pastinaca sativa L., P. hirsuta Pancic., Tordylium maximum L., Physospermum cornubiense (L.) DC., Peucedanum alsaticum L., P. oreoselinum (L.) Moench, P. cervaria (L.) Cuss., P. austriacum (Jacq.) Koch, P. longifolium W. et K., and P. officinale L. All of these species grow wild in the central part of the Balkan Peninsula. The essential oils were found to be complex mixtures of various compounds, more than 100 constituents being in each taxon, with contributions of main products never exceeding 25% of the total content. Sesquiterpene hydrocarbons were found to be the main group of constituents of all taxa, except for Peucedanum species, where monoterpene hydrocarbons were identified as the main components. The chemotaxonomic value of the essential-oil composition is discussed according to results of principal-component analysis (PCA). The essential-oil composition mainly reflects current taxonomic relationships between the investigated taxa.  相似文献   

3.
Lepidopilum grevilleanum Mitt., long considered a synonym ofL. affine C. Müll., is a distinct and rare species of western Ecuador.Lepidopilum affine is widespread, presently known from the western and northern Amazon basin, Atlantic region of northern South America, and the Pacific coastal region of Central America. Several new synonyms are proposed forLepidopilum affine: L. allionii Broth.,L. ambiguum Broth.,L. antisanense Bartr.,L. mittenii C. Müll.,L. obtusulum C. Müll., andL. subobtusulum Broth.Lepidopilum pulcherrimum Steere is a synonym ofL. grevilleanum.  相似文献   

4.
不同花卉抗氧化能力及其多酚、黄酮含量比较   总被引:15,自引:0,他引:15  
对多种花卉花瓣水提液的抗氧化能力及其多酚、黄酮相对含量进行了测定,结果表明:蔷薇属植物Rosa L.和大花紫薇(Lagerstioemia indica L.)花瓣水提液的抗氧化活性最强,铁海棠(Euphorbia anttquorum L.)、杜鹃花(Rhododendron mucronatum G.Don)和桂花(Osmanthus fragrans Lour.)次之.各种花瓣水提液抗氧化活性与多酚含量密切相关.讨论了玫瑰、杜鹃花、桂花和大花紫薇在天然抗氧化剂、抗氧化功能食品和医药保健相关领域的广阔开发前景.  相似文献   

5.
6.
Six new species of the genus Lasiosyne Tan et al., 2007, the type genus of the family Lasiosynidae Kirejtshuk et al., 2010, are described from Jurassic and Lower Cretaceous deposits of Mongolia and East Siberia: L. shartegiensis sp. nov., L. insculpta sp. nov., L. longitarsa sp. nov., L. cataphracta sp. nov., L. punctata sp. nov., and L. decora sp. nov. A modified diagnosis of the genus is proposed.  相似文献   

7.
Male Sterility and Anther Wall Structure in Copper-deficient Plants   总被引:5,自引:0,他引:5  
DELL  B. 《Annals of botany》1981,48(5):599-608
Anther development and pollen sterility were followed in plantsof wheat, oat, barley, sweetcorn, sunflower, petunia and subterraneumclover grown at a range of copper supplies. Copper-deficientplants had increased pollen sterility. Lignified wall thickenings were reduced or absent in the endotheciaof anthers from Cu-deficient plants. Reduced seed set may resultboth from reduced pollen fertility or failure of the stomiato rupture due to decreased lignification of anther walls. Triticum aestivum L., wheat, Hordeum vulgare L., barley, Avena sativa L., oat, Zea mays L., corn, sweetcorn, maize, Helianthus annuus L., sunflower, Petunia hybrida L., Trifolium subterraneum L., subterranean clover, male sterility, anther development, copper deficiency  相似文献   

8.
Chromosome numbers of 21 taxa in Lobelia L. and Cyphia Berg, are reported, the majority being new records. 2n = 18 in Cyphia is a new generic report. The new species Lobelia paludigena Thulin (Zaire), L. kundelungensis Thulin (Zaire), L. cheranganiensis Thulin (Kenya) and L. corniculata Thulin (Swaziland and Natal) are described. The distributions of these species, as well as of L. thermalis Thunb., are mapped. L. kalobaënsis E. Wimm. ex Thulin is validated. The new combinations L. trullifolia Hemsl. ssp. delicatula (Compton) Thulin and L. flaccida (Presl) A. DC. ssp. gnmvikii (T. C. E. Fries) Thulin are made. Typifications are provided for the following names: L. stuhlmannii Schweinf. ex Stuhlm., L. gregoriana Bak. f., L. fervens Thunb., L. anceps L. f. and L. depressa L. f.  相似文献   

9.
During our investigation on microfungi in North Rhine Westphalia in the years 2002 and 2003 we were able to collect and identify some new and rare species of microfungi as parasites and saprophytes on wild and ornamental plants. Some of these like Erysiphe elevata (BURILL.) U. BRAUN & S. TAKAMATSU COMB. NOV. [=Microsphaera elevata BURILL.] on Catalpa bignonioides WALT., Erysiphe syringae-japonicae (U. BRAUN) U. BRAUN & S. TAKAMATSU [= Microsphaera syringae-japonicae U. BRAUN, M. aceris BUNKINA. KOMAROVSKIE CHTENIYA, Erysiphe acerina U. BRAUN & S. TAKAMATSU] on Acer campestre L. and Acer barinerve L., Mycosphaerella iridis (DESM.) SCHROET., Ectostroma iridis FR. and Volutella melaloma BERK. & BR on Iris pseudacorus L., Puccinia doronicella P. SYD. & SYD. on Doronicum columnae TEN., Ascochyta lamiorum SACC. S.L. I=A. phlomidis BUB. & WROB.) on Phlomis tuberosa L., Colletotrichum gloeosporides (PENZ.) SACC. on Passiflora coerulea L., Oidium hortensiae JOERST on Hydrangea macrophylla (THUNB.) SER., Puccinia horiana P. HENN. on Chrysanthemum vulgare (L.) BERNH., Lophodermium pinastri (SCHRAD.) CHEV., Leptostroma pinorum SACC., Sclerophoma pythiophila (CDA) HOHN., Lichenoconium boreale (KARST.) PETRAK. & SYD., Anthostomella formosa KIRSCHST. and Sphaeropsis sapinae (FR.) DYKO & SUTTON on Pinus nigra L. are new for Germany. All samples are located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.  相似文献   

10.
Various angiosperms differed in their monovinyl and divinyl protochlorophyllide biosynthetic capabilities during the dark and light phases of photoperiodic growth. Some plant species such as Cucumis sativus L., Brassica juncea (L.) Coss., Brassica kaber (DC.) Wheeler, and Portulaca oleracea L. accumulated mainly divinyl protochlorophyllide at night. Monocotyledonous species such as Avena sativa L., Hordeum vulgare L., Triticum secale L., Zea mays L., and some dicotyledonous species such as Phaseolus vulgaris L., Glycine max (L.) Merr., Chenopodium album L., and Lycopersicon esculentum L. accumulated mainly monovinyl protochlorophyllide at night.

Under low light intensities meant to simulate the first 60 to 80 minutes following daybreak divinyl protochlorophyllide appeared to contribute much more to chlorophyll formation than monovinyl protochlorophyllide in species such as Cucumis sativus L. Under the same light conditions, species which accumulated mainly monovinyl protochlorophyllide at night appeared to form chlorophyll preferably via monovinyl protochlorophyllide.

These results were interpreted in terms of: (a) a differential contribution of monovinyl and divinyl protochlorophyllide to chlorophyll formation at daybreak in various plant species; and (b) a differential regulation of the monovinyl and divinyl protochlorophyllide biosynthetic routes by light and darkness.

  相似文献   

11.
In order to investigate the taxonomic value of a number of characters in the elucidation of relationships within the collective genus Polygonum L., and segregate genera Atraphaxis L., Calligonum L., Pteropyrum Jaub. & Spach., Oxygonum Burch., Fagopyrum Mill., Harpagocarpus Hutch. & Dandy and Polygonella Michx., 83 species of the tribe Polygoneae emend. Jaretzky were studied. The following floral characters were examined: stamen number, insertion and external morphology; structure and morphology of the floral nectaries; vasculature and surface morphology of the tepals.
Problems in floral morphology in Polygonaceae are discussed, together with relationships within the Family. The tribal division proposed by Haraldson (1978) is supported, but a new and different delimitation of genera is proposed. The present data support a division of Polygonum L. sensu lato and its related taxa into two tribes: Polygoneae (containing Polygonum L. sensu stricto, Fallopia Adans., Oxygonum Burch., Pteropyrum Jaub. & Sparh., Atraphaxis L. and Calligonum L.), and Persicarieae (containing Fagopyrum Mill., Harpagocarpus Hutch. & Dandy, Persicaria Mill. and Koenigia L.). The genus Reynoutria Houtt. is included as a section of Fallopia Adans.; Bislorta Mill., Aconogonon Reichenb. and Tovara Adans. are included within Persicaria Mill.
A number of new combinations are proposed in Persicaria and Fallopia .  相似文献   

12.
对丽盲蝽属 (丽盲蝽亚属 )Lygocoris (subg .Lygocoris)的中国种类作了修订。文中共包括 19个种 ,其中有 12新种 ,1个中国新纪录种 ,并包括 1项新等级的认定。即暗胝丽盲蝽L .(L .)calligersp .nov .(正模 :四川峨眉山九老洞 ) ,程氏丽盲蝽L .(L .)chengisp .nov .(正模 :四川峨眉山大乘寺 ) ,晕斑丽盲蝽L .(L .)diffusomaculatussp .nov .(正模 :甘肃榆中兴隆山 ) ,淡色丽盲蝽L .(L .)dilutussp .nov .(正模 :甘肃夏河县合作 ) ,锈褐丽盲蝽L .(L .) ferrugineussp .nov .(正模 :云南哀牢山 ) ,褐盾丽盲蝽L .(L .) fuscoscutel latus (Reuter ,190 6 )stat .nov .[由L .(L .)striicornisvar.fuscoscutellatus升为种级阶元 ],广西丽盲蝽L .(L .) guangxiensissp .nov .(正模 :广西龙胜 ) ,东亚丽盲蝽L .(L .)idoneus(Linnavuori,196 3) (中国新纪录种 ) ,完脊丽盲蝽L .(L .)integricarinatussp .nov .(甘肃榆中麻家寺 ) ,林氏丽盲蝽L .(L .)linnavuoriisp .nov .(云南哀牢山簸箕坝 ) ,长翅丽盲蝽L .(L .)longipennis (Reuter ,190 6 ) ,斑盾丽盲蝽L .(L .)maculis cutellatussp .nov .(四川理县刷经寺 ) ,原丽盲蝽L .(L .) pabulinus (Linnaeus ,176 1) ,红盾丽盲蝽L .(L .)rufiscutellatussp .nov .(甘  相似文献   

13.
The multidomain bacterial surface protein L (PpL) is a virulence factor expressed by only 10% of Peptostreptococcus magnus strains, and its expression is correlated with bacterial vaginosis. The molecular basis for its ability to recognize 60% of mammalian immunoglobulin light chain variable regions (V(L)) has been described recently by x-ray crystallography, which suggested the presence of two V(L) binding sites on each protein L domain (Graille, M., Stura, E. A., Housden, N. G., Beckingham, J. A., Bottomley, S. P., Beale, D., Taussig, M. J., Sutton, B. J., Gore, M. G., and Charbonnier, J. (2001) Structure 9, 679-687). Here, we report the crystal structure at 2.1 A resolution of a protein L mutant complexed to an Fab' fragment with only 50% of the V(L) residues interacting with PpL site 1 conserved. Comparison of the site 1 interface from both structures shows how protein L is able to accommodate these sequence differences and therefore bind to a large repertoire of Ig. The x-ray structure and NMR results confirm the existence of two V(L) binding sites on a single protein L domain. These sites exhibit a remarkable structural mimicry of growth factors binding to their receptors. This could explain the protein L superantigenic activity on human B lymphocytes.  相似文献   

14.
Essential oils extracted from different plants (Anthemis nobilis L., Artemisia dracunculus L., Cannabis sativa L., Cupressus sempervirens L., Cymbopogon citratus (DC.) Stapf., Curcuma longa L., Foeniculum vulgare L., Hypericum perforatum L., Hyssopus officinalis L., Mentha spicata L., Monarda didyma L., Ocimum basilicum L., Ocotea quixos Kosterm., Origanum vulgare L., Pinus nigra J.F. Arnold, Pinus silvestris L., Piper crassinervium Kunth., Rosmarinus officinalis L., Salvia officinalis L., Salvia sclarea L., Santolina chamaecyparissus L., Thymus vulgaris L., Zingiber officinaie L.) were screened in guinea pig and rat plasma in order to assess antiplatelet activity and inhibition of clot retraction. The oils were chemically analysed and a relationship between components and ability to affect hemostasis was evidenced. O. quixos, F. vulgaris, and A. dracunculus showed the highest antiplatelet activity against ADP, Arachidonic Acid and the Thromboxane A2 agonist U46619 (IC50, 4-132 microg ml(-1)), and a good ability to destabilize clot retraction (IC50, 19-180 microg ml(-1)). For these oils a significant correlation between antiplatelet potency and phenylpropanoids content (54-86%) was evidenced thus suggesting a key role for this moiety in the prevention of clot formation. These findings provide the rationale to take in account the antiplatelet activity in the pharmacological screening of natural products containing phenylpropanoids.  相似文献   

15.
The morphology of seeds and achenes of the British members ofthe Plantaginaceae has been examined. Keys to the identificationof seeds in the genera Plantago and Littorella are presented.Quantitative data on size and weight, as well as informationabout shape, colour and surface features of the seeds are givenfor: Plantago major L., P. media L., P. lanceolata L., P. martimaL., P. coronopus L., P. indica L., P. sempervirens Crantz, andLittorella uniflora (L.) Aschers. A representative sample ofeach seed is illustrated.  相似文献   

16.
A new species, Phaeomarasmius borealis , is described and a number of new combinations and names are proposed: Boletus luridiformis var. junquilleus comb, nov., Fayodia anthracobia comb, nov., Flagelloscypha mairei comb, nov., Hemimycena gypsella comb, nov., H. subimmaculata comb, nov., Hypholoma eximium comb. nov., Lentinus schaefferi comb, nov., Lyophyllum gangraenosum comb, nov., L. fusisporum comb, nov., L. confusum comb, nov., Micromphale acicola nom. nov., M. rufocarneum comb, nov., Pseudoomphalina absinthiata comb, nov., Psilocybe magnivelaris comb, nov., and Sericeomyces sericifer comb. nov.  相似文献   

17.
Plants traditionally used to dye carpets and woven matting in the eastern Mediterranean region were investigated. The survey was carried out in Kadirli, Feke, Aladağ, the surrounding villages of Adana, and in Osmaniye (Turkey). According to the survey results, 37 species of plants belonging to 29 families were used in natural dye production. The total dye contents of collected plants ranged from 1.5% to 10.0%. Mordants and dyes obtained from some of these plants were used to treat wool yarn and the yarn's dyed properties were tested. Some of the plants were also examined in terms of cultivation and fifteen were transferred to a Dye Plants Collection Garden. They were Alnus glutinosa (L.) Gaertn. ssp. antitaurica Yalt., Arctium minus ssp. pubens (Bab.) Arènes, Chrysanthemum segetum L., Cistus creticus L., Cotinus coggygria Scop., Datisca cannabina L., Galium verum ssp. glabrescens Ehrend., Isatis tinctoria ssp. tomentella (Boiss. & Balansa) P.H.Davis, Melissa officinalis ssp. inodora Bornm., Mentha longifolia (L.) Huds. ssp. longifolia , Reseda lutea var. lutea L., Rhamnus oleoides ssp. graecus (Boiss. & Reut.) Holmboe, Rhus coriaria L., Rubia tinctorum L., and Rumex patientia L.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 71–77.  相似文献   

18.
19.
Human lipocortin I is a 38.5-kDa phospholipase A2 inhibitor that has been produced in Escherichia coli in large quantities by recombinant DNA technology (Wallner, B.P., Mattaliano, R.J., Hession, C., Cate, R. L., Tizard, R., Sinclair, L.K., Foeller, C., Chow, E.P., Browning, J.L., Ramachandran, K.L., and Pepinsky, R.B. (1986) Nature 320, 77-80). To localize the region within the protein responsible for its inhibitory activity, we generated a series of fragments of the recombinant product by limited proteolysis with elastase and characterized their structure by sequencing and peptide mapping. Five active fragments have been analyzed in detail. The smallest is an 18-kDa fragment derived from the amino-terminal half of lipocortin. Three of the larger fragments contain this region. The fifth fragment is missing 83 amino acids from the amino terminus. A region common to all the active fragments (amino acid residues 97-178) is 70% homologous with the corresponding region from a second member of the lipocortin family which recently was cloned (Huang, K-S., Wallner, B.P., Mattaliano, R.J., Tizard, R., Burne, C., Frey, A., Hession, C., McGray, P., Sinclair, L.K., Chow, E.P., Browning, J.L., Ramachandran, K.L., Tang, J., Smart, J.E., and Pepinsky, R.B. (1986) Cell 46, 191-199) and thus presumably is important for activity. In addition to inhibitory fragments, we have isolated a 3-kDa proteolytic fragment from the amino terminus of lipocortin I that contains the known phosphorylation site for protein-tyrosine kinases. Because of sequence homology of the 3-kDa fragment with biologically active synthetic peptides from pp60v-src and middle T antigen, its release by proteases may represent an important part of the activity of lipocortin.  相似文献   

20.
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