共查询到20条相似文献,搜索用时 78 毫秒
1.
Foliar appendages of eight species ofSalvia L. have been studied. Eleven types of non glandular and five types of glandular appendages have been observed. They have been classified under three major categories: (1) glandular capitate; (2) non glandular filiform and (3) non glandular capitate. Five new types of trichomes have been reported fromLamiaceae for the first time. On the basis of trichome types different species ofSalvia can be identified. A tentative key has been presented. 相似文献
2.
Comparative scanning electron microscope (SEM) study of miracidia of four human schistosome species 总被引:1,自引:0,他引:1
D T Eklu-Natey J Wüest Z Swiderski H P Striebel H Huggel 《International journal for parasitology》1985,15(1):33-42
The miracidia of four human blood flukes, Schistosoma haematobium, S. intercalatum, S. mansoni and S. japonicum, have been studied by means of the scanning electron microscope (SEM). Differences have been observed in their respective dimensions, in the configuration of their terebratoria (apical papillae), in the shape of the epidermal plates, and in the distribution of the sensory receptors. The most evident differences have been noticed on the terebratoria where two main patterns of organization of the anastomosing membrane foldings have been described: (1) a ‘rosette’ pattern observed in S. haematobium and S. intercalatum and (2) a ‘honeycomb’ pattern in S. mansoni and S. japonicum. The structure and the taxonomic importance of these morphological features are analysed. 相似文献
3.
In the present work, novel heterotrophic nitrifying and aerobic denitrifying bacteria have been isolated from greenwater system of coastal aquaculture. Based on the 16S rRNA gene, FAME analysis and biochemical test, the isolates have been identified as Pseudomonas aeruginosa and Achromobacter sp. These have been named as P. aeruginosa strain DBT1BNH3 and Achromobacter sp. strain DBTN3. Denitrifying functional genes such as nitrite reductase (nirS), nitric oxide reductase (qnorB) and nitrous oxide reductase (nosZ) genes have been identified. These strains found to have a 27 kb plasmid coding for nirS and nosZ. The possibility of horizontal transfer of plasmid among Pseudomonadaceae and Alcaligenaceae families in coastal aquaculture has been explored. Further, we have studied combined nitrification and oxygen tolerant denitrification potential in the same isolates. 相似文献
4.
Three indole alkaloids have been isolated from Alstonia macrophylla Wall. Two of these have been identified as affinisine (I) and picrinine (II). The third, a new base designated picralstonine, has been shown to possess structure (III). 相似文献
5.
Two new 4-quinazolone alkaloids have been isolated from seed husks of Zanthoxylum arborescens. Based on their spectroscopic properties they have been assigned structures, 1-methyl-3-(2′-phenylethyl)-1H,3H-quinazoline-2,4-dione and 1-methyl-3-[2′-(4″-methoxyphenyl)ethyl]-1H,3H-quinazoline-2,4-dione. These structural assignments have been confirmed by synthesis. Skimmianine has been obtained from leaf extracts of Z. dimoncillo and Z. caribaeum while skimmianine and scopeletin have been isolated from leaf extracts of Z. fagara. 相似文献
6.
Andrés Garcia-Granados Antonio Martínez M.Esther Onorato Oswaldo Socorro 《Phytochemistry》1984,23(3):607-610
Several new 14-hydroxybeyerene acetates have been isolated from the aerial parts of Sideritis pusilla subsp. flavovirens. In addition, an ent-kaur-15-ene (siderol) and a new ent-7α, 18-dihydroxybeyer-15-ene (flavovirol) have been obtained from the same source. The structures of these new acetates have been established by chemical and spectroscopic means and the structure of flavovirol has been confirmed by 13C NMR. 相似文献
7.
8.
Graham K. Moore George A.F. Roberts 《International journal of biological macromolecules》1982,4(4):246-249
Fully subtituted di-O-acetyl-N-acetylchitosan (chitin diacetate) has been prepared by a route in which the hydroxyl groups are acetylated prior to N-acetylation. This overcomes the previously reported intramolecular steric hindrance to esterification caused by the N-acetamido group. The resultant products were of high viscosity but had a limited solubility range. Di-O-acrylcarbamate derivatives of N-acetylchitosan (chitin) have been produced by a similar route, whilst di-O-arylcarbamate-N-arylureidochitosans have been prepared directly from chitosan. These products also have limited solubility ranges and have inherent viscosities similar to that of di-O-acetylchitosan prepared from the same batch of chitosan. 相似文献
9.
《Phytochemistry》1987,26(2):543-545
(19R)-Epimisiline and (19S)-epimisiline, two new Aspidosperma alkaloids, have been isolated from the leaves of Petchia ceylanica. The structures have been deduced on the basis of chemical and spectroscopic data. 相似文献
10.
Sarah R. Hemingway Peter J. Houghton J.David Phillipson Edward J. Shellard 《Phytochemistry》1975,14(2):557-563
Speciofoline has been assigned the epiallo B configuration on the basis of isomerization studies, NMR and CD spectra, and three new speciofoline isomers, mitrafoline (allo A), isomitrafoline (allo B) and isospeciofoline (epiallo A) have been isolated from Mitragyna speciosa Korth. Two new C-20 vinyl alkaloids, rotundifoleine and isorotundifoleine, have been separated as minor products from crystalline samples of rotundifoline and isorotundifoline respectively, previously isolated from M. parvifolia (Roxb.) Korth. A transient product observed during the isomerization of isorotundifoline has been identified as the pseudo B isomer, 3-epi-isorotundifoline. 相似文献
11.
A comparative analysis involving 21 mandibular metric characteristics of Martes zibellina (n = 114), M. martes (117), M. foina (110), and M. melampus (6) has been performed using a graphical method (scatter diagrams) and stepwise discriminant analysis. The best metric characteristics allowing for discrimination between the lower jaws of these species have been identified and used to plot scatter diagrams. The discriminant analysis has been conducted for three groups of characteristics, namely, those of the whole mandible, ramus ascendens, and corpus mandibulae. As a result, optimal statistical models based on the diagnostic characteristics have been constructed and tested. The corresponding classification functions for species identification of whole mandibles and their fragments have been calculated. These results can be used for species identification of the mandibles of M. zibellina, M. martes, M. foina, and M. melampus. 相似文献
12.
From the Japanese quassia tree, Picrasma quassioides (Simaroubaceae), new bitter principles (simaroubolides), picrasin A, B, C, D, E, F and G have been isolated whose stereostructures have been elucidated on the basis of chemical and physical evidence. The relative bitterness of the picrasins and the related simaroubolides has been measured. 相似文献
13.
《Phytochemistry》1986,25(6):1443-1447
Two novel alkaloids 3β,4α,13α-trihydroxylupanine and 3β,4α-dihydroxy 13α-O-(2'-pyrrolylcarbonyl)-lupanine (calpaurine) have been isolated from the leaves of Ethiopian Calpurnia aurea subsp. aurea. In addition, lupinine and epilupinine (both new for the genus), calpurmenine and calpurmenine pyrrolecarboxylic acid ester (previously found in subsp. sylvatica but not in subsp. aruea) have been isolated together with 13-hydroxylupanine, its tiglate and pyrrolecarboxylic acid esters (calpumine), virgiline and virgiline pyrrolecarboxylic acid ester, alkaloids which have been reported previously from subsp. aruea. 相似文献
14.
Fifteen acetylenic compounds have been isolated and characterized from the flower heads of Chrysanthemum leucanthemum L. Five of these acetylenes have not previously been published as naturally occurring compounds. These are: 1,7(c)-hexadecadien-10,12,14-triyne; 1,8(c)-heptadecadien-11,13,15-triyne; 4(c)-tridecen-7,9,11-triyn-l-ol; 1,8(t)-hexadecadien-10,12,14-triyn-(6·7)-oxirane; and [3(t),5(t)-tridecadien-7,9,11-triyn-l-yl]-3-methyl-2-butenoate. The first three compounds are interesting since they are important intermediates in previously postulated biogenetic pathways. Ten acetylenes have been identified from the roots of the same plant, all of these having different structures from those of the flower heads. One of the acetylenes, [3(t), 5(t)-tridecadien-7,9,11-triyn-l-yl]-3-methylbutyrate, from the roots has never been reported as a naturally occurring compound. 相似文献
15.
Rawson DJ Brugier D Harrison A Hough J Newman J Otterburn J Maw GN Price J Thompson LR Turnpenny P Warren AN 《Bioorganic & medicinal chemistry letters》2011,21(12):3771-3773
A potent series of substituted (2S,4S)-benzylproline α2δ ligands have been designed from the readily available starting material (2S,4R)-hydroxy-l-proline. The ligands have improved pharmacokinetic profile over the (4S)-phenoxyproline derivatives described previously and have potential for development as oral agents for the treatment of neuropathic pain. Compound 16 has been progressed to clinical development. 相似文献
16.
Crocodylian remains are collected in 39 fossil-bearing localities but only in seven localities specimens with reliable taxonomic attributions, at least to genus level have been collected. Three species have been reported from the early Lutetian Purga di Bolca site: Pristichampsus cf. Pristichampsus rollinati, Asiatosuchus sp., Hassiacosuchus sp. (=Allognathosuchus sp.). The three crocodilians discovered at Purga di Bolca have been reported also from Geiseltal and Messel (Middle Eocene, Germany). Bolca at that time was part of a Tethysian archipelago and no mammals have been found there till now. Crocodilians and turtles clearly arrived from the European mainland across a marine water barrier. Among the other fossiliferous localities of Veneto, very interesting is the Monte Zuello site, of late Middle Eocene age, yielding a longirostrine crocodilian, Megadontosuchus arduini, a tomistomine species. Tomistomines are known in contemporaneous sediments of both Europe and Africa, but the European forms Dollosuchus and Kentisuchus seem the closest taxa. Remains of Oligocene age have been collected in Veneto and Liguria, but the fossils discovered in the second region are teeth or fragmented bones. The fossil crocodilians of Monteviale (Veneto), of Early Oligocene age, have been assigned to two species but they have been recently all identified as Diplocynodon ratelii, known from several European sites of Late Eocene, Oligocene and Miocene age. This species arrived in the Monteviale area from the European mainland across a narrow sea. Several crocodilian fossils of Miocene age are very fragmentary or represented by isolated teeth. In the Middle and Late Miocene of Sardinia, a well-established species, Tomistoma calaritanum is present. Remains of Tomistoma of the same age have been reported in some localities in Tuscany, Apulia, Sicily and Malta. In the Mediterranean area, the genus is known from European and African sites (of older age). The colonisation of Europe by this genus is the result of a dispersion from Africa (or less probably from Asia). During Late Miocene Sardinia and Tuscany belong to the same palaeobioprovince characterized by the Oreopithecus-Maremmia fauna. In Tuscany, a crocodilian identified as Crocodylus bambolii is present in the late Miocene site of Monte Bamboli. If the generic attribution of this form is correct, its ancestors must have arrived from Africa. Another fossil assemblage of Late Miocene age characterizes the Apulia-Abruzzi palaeobioprovince (Hoplitomeryx-Microtia fauna) and testifies complete isolation between the two palaeobioprovinces. In this last area, remains of Crocodylus sp. have been collected in coastal sandstones at Scontrone (Abruzzi) and in several fissure fillings of Gargano of slightly younger age. The ancestors of this species arrived from Africa while no African elements are present among the mammalian fauna. The dispersion of the genus Crocodylus in the Italian palaeoislands may have taken place once, with allopatric differentiation of the two populations (Tuscany-Sardinia and Apulia-Abruzzi) or twice with independent colonisation of each area. 相似文献
17.
Cutillo F D'Abrosca B DellaGreca M Di Marino C Golino A Previtera L Zarrelli A 《Phytochemistry》2003,64(8):1381-1387
Seven cinnamic acid amides have been isolated from Chenopodium album. The structures have been attributed by means of their spectral data. One of them, N-trans-4-O-methylferuloyl 4′-O-methyldopamine, is described for the first time. Their effects on germination and growth of dicotyledons Lactuca sativa L. (lettuce) and Lycopersicon esculentum L. (tomato) and of monocotyledon Allium cepa L. (onion) as standard target species have been studied in the range concentration 10−4-10−7 M. 相似文献
18.
Assembly of bacteriophage T4 tail fibers. IV. Subunit composition of tail fibers and fiber precursors 总被引:8,自引:0,他引:8
R C Dickson 《Journal of molecular biology》1973,79(4):633-647
Using a novel purification procedure, the protein composition of the tail fibers of bacteriophage T4 has been determined. Fibers contain four proteins whose molecular weights, as estimated by sodium dodecyl sulfate/acrylamide gel electrophoresis, are 150,000, 125,000, 40,000 and 24,000. The two largest proteins have been previously identified as the products of genes 34 (P34) and 37 (P37), respectively (King and Laemmli, 1971; Ward and Dickson, 1971). The two smaller proteins have now been identified as the products of genes 35 (P35) and 36 (P36), respectively. The products of the two other known phage genes required for fiber assembly, 38 and 57, have been identified as non-structural phage proteins with molecular weights of 26,000 and 10,000, respectively. 相似文献
19.
《Journal of Molecular Catalysis .B, Enzymatic》2010,62(3-4):279-283
Cancer chemopreventive agent (S)-5-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione and its counterpart (R)-acetate have been obtained through a lipase-catalyzed transesterification process in organic solvent. Candida antarctica lipase B and Pseudomonas cepacia lipase have demonstrated their potential as excellent biocatalysts for the production of enantiomerically pure compounds under mild reaction conditions. At the same time different commercially available alcohol dehydrogenases have been tested in the bioreduction of the corresponding naphthoquinone in an aqueous system. Biologically active (S)-alcohol has been isolated in enantiopure form with different conversion values depending on the biocatalyst employed and the reaction conditions. 相似文献