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1.
Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.  相似文献   

2.
Eight linear furocoumarins and three coumarins were isolated and identified from Thamnosma texana. They were xanthotoxin, imperatorin, bergapten, alloimperatorin methyl ether epoxide, heraclenin, isopimpinellin, psoralen, oxypeucedanin, and the coumarins herniarin, osthol and thamnosmin. The linear furocoumarins appear to be agents that account for the known photosensitizing properties of Thamnosma texana, and consequently its colloquial name, ‘blisterweed.’ This is the first report on the occurrence of imperatorin, heraclenin, oxypeucedanin, herniarin or osthol in any Thamnosma species.  相似文献   

3.
The present paper documents the morphology and systematic positions of three new oligotrich ciliates, P arallelostrombidium obesum sp. nov. , P arallelostrombidium ellipticum sp. nov. , and S trombidium tropicum sp. nov. , which were sampled from habitats with different salinities in southern China. P arallelostrombidium obesum sp. nov. is characterized by a fat body and the posterior portions of the girdle and ventral kineties extending transversely on the dorsal side. P arallelostrombidium ellipticum sp. nov. is recognizable by the anterior ends of the girdle and ventral kineties being close to each other and the posterior ends of the girdle and ventral kineties intersecting on the dorsal side. S trombidium tropicum sp. nov. is distinguished by a ventrally opened girdle kinety that is slightly spiralled with the right end shifted posteriad. Small subunit rRNA gene trees show that P . obesum sp. nov. and P . ellipticum sp. nov. fall into a mixed group composed of Parallelostrombidium and some Novistrombidium species, and that S . tropicum sp. nov. branches at the base of the clade containing non‐Strombidium species. The relationships of Parallelostrombidium species and that of Strombidium species are both not resolved considering their low support values in our phylogenetic analysis. © 2015 The Linnean Society of London  相似文献   

4.
The type specimens ofCyrtoceras ellipticum Lossen 1860 and proposedly conspecific material from Baltic erratic boulders of late Llanvirn (Lasnamägian) age are closely similar toPhthanoncoceras oelandense Evans & King 1990 from the latest Arenig (early Kundan) of Sweden.Cyrtoceras priscum Eichwald 1861, co-occurring withC. ellipticum, is generically distinct in its short living chamber and much more advanced siphuncular structure; it probably representsOonoceras lineage. The type ofOrthoceras damesi Krause 1877 from the Baltic Beyrichienkalk erratic boulders, which is smooth, except for faint growth lines, appears to represent a later ontogenetic stage in development of a kionoceratid with prominent longitudinal riblets and annulations at early stages. It is probably a derivative of the main longiconic lineage ofSpyroceras, in which prominent conch ornamentation disappeared in adult specimens.  相似文献   

5.
Oxidative stress caused by neutrophils is an important pathogenic factor in trauma/hemorrhagic (T/H)-induced acute lung injury (ALI). Osthol, a natural coumarin found in traditional medicinal plants, has therapeutic potential in various diseases. However, the pharmacological effects of osthol in human neutrophils and its molecular mechanism of action remain elusive. In this study, our data showed that osthol potently inhibited the production of superoxide anion (O2•−) and reactive oxidants derived therefrom as well as expression of CD11b in N-formylmethionylleucylphenylalanine (FMLP)-activated human neutrophils. However, osthol inhibited neutrophil degranulation only slightly and it failed to inhibit the activity of subcellular NADPH oxidase. FMLP-induced phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) was inhibited by osthol. Notably, osthol increased the cAMP concentration and protein kinase A (PKA) activity in activated neutrophils. PKA inhibitors reversed the inhibitory effects of osthol, suggesting that these are mediated through cAMP/PKA-dependent inhibition of ERK and Akt activation. Furthermore, the activity of cAMP-specific phosphodiesterase (PDE) 4, but not PDE3 or PDE7, was significantly reduced by osthol. In addition, osthol reduced myeloperoxidase activity and pulmonary edema in rats subjected to T/H shock. In conclusion, our data suggest that osthol has effective anti-inflammatory activity in human neutrophils through the suppression of PDE4 and protects significantly against T/H shock-induced ALI in rats. Osthol may have potential for future clinical application as a novel adjunct therapy to treat lung inflammation caused by adverse circulatory conditions.  相似文献   

6.
Fossil wood collections at the Natural History Museum, London, were searched for the type material of two important species, described as early as 1831 by Witham, on the basis of material at least partly furnished by Nicol and collected in the Liassic of Whitby (Yorkshire, UK). The names given to these two species by Witham are the basionyms for more than ten other species names, while these species names also provide syntypes for several generic names. Despite this, the original material has been only rarely and partly revised, leading to much confusion.We managed to locate some of the original material. Several topotypes were also studied. On the basis of this review we propose here a neotypification for Peuce huttoniana Witham, a lectotypification for Cupressinoxylon barberi Seward and a lectotypification for Tiloxylon Hartig. We evidence several taxonomical and nomenclatural synonymies, assign Peuce lindleyana Witham to Protocedroxylon and P. huttoniana to Xenoxylon Gothan, and introduce the new combination Xenoxylon huttonianum (Witham) nov. comb. as the correct name for Xenoxylon ellipticum Gottwald & Holleis ex Schultze-Motel.A topotype of Araucariopitys americana Hollick & Jeffrey was also reviewed, which, together with previous results, leads us to suggest that Araucariopitys Hollick & Jeffrey, Protocedroxylon Gothan and Planoxylon Stopes should not be considered as taxonomical synonyms. This point is crucial to the interpretation of the fossil record of Early Abietinae.  相似文献   

7.
《Palaeoworld》2021,30(3):538-550
Charophyte assemblages from the Cretaceous/Paleogene (K/Pg) boundary transition in the JZK-2 borehole of the Jiaolai Basin (eastern China) were studied. The charophyte flora includes Tolypella grambastii, Peckichara praecursoria, Microchara cristata, Microchara prolixa, Chara changzhouensis, Lamprothamnium ellipticum, Nodosochara (Turbochara) specialis, Lychnothamnus aff. vectensis, and Lychnothamnus lanpingensis n. comb. The discovery of the ostracod species Porpocypris sphaeroidalis Guan in the upper section of the JZK-2 borehole strongly indicates the arrival of the Paleocene. Three floras of the latest Cretaceous to the early Paleocene were compared among the Jiaolai, Pingyi, and Songliao basins. The Pingyi Basin is special because it is the only carbonate palaeolake that occurred throughout the K/Pg transition in China. It is characterized by the appearance of the Cretaceous brackish water element, Feistiella anluensis (Wang), and is dominated by the Paleocene species, Peckichara varians Grambast. The Songliao and Jiaolai floras grow in clastic lakes; the Jiaolai Basin is thought to correspond to an altitude lake, which was formed in the coastal mountains with high palaeoelevation (≥ 2.0 km), while the Songliao Basin is presumed to have been formed in a low elevation site according to previous studies. This difference in altitude explains why the Songliao Basin is more species-rich than the Jiaolai Basin.  相似文献   

8.
Warren Steck 《Phytochemistry》1973,12(9):2283-2286
Roots of Lomatium macrocarpum (Hook. & Arn.) C. & R. yielded osthol (7-methoxy-8-[3-methyl-2-butenyl]-coumarin) and a chromone, 2-methyl-5-hydroxy-6-[3-methyl-2-butenyl]-7-methoxychromone, identified spectroscopically and by synthesis. The aerial parts of the plant also contained this chromone along with sibiricin (5,7-dimethoxy-8-[3-methyl-2,3-epoxybutyl]-coumarin) and a new coumarin named macrocarpin. By spectroscopy and chemical degradation macrocarpin was shown to be 7-methoxy-8-(3-methyl-4-[2-methyl-cis-2-butenoyloxy]-cis-2-butenyl)coumarin. These products were not found in four other Lomatium species examined.  相似文献   

9.
An acylphloroglucinol, elliptophenone A, and two xanthones, elliptoxanthone A and elliptoxanthone B, were isolated from the aerial portions of Hypericum ellipticum together with three known xanthones, 1,3,7-trihydroxy-8-(3-methyl-2-butenyl)-9H-xanthen-9-one, 1,6-dihydroxy-4-methoxy-9H-xanthen-9-one, and 1,4,5-trihydroxy-9H-xanthen-9-one. Their structures were determined by spectroscopic analyses. The acylphloroglucinol and xanthones were evaluated for cytotoxicity using three human colon cancer cell lines cell lines (HT-29, HCT-116 and Caco-2) and a normal human colon cell line (CCD-18Co).  相似文献   

10.
The Oceanian plant genus Spiraeanthemum (Cunoniaceae) has a centre of diversity in New Caledonia, where it is represented by seven species. Its diversification was investigated using two low‐copy nuclear genes, ncpGS and GapC, and phylogenetic analyses were based on maximum parsimony, maximum likelihood and recombination networks. We detected several cases of gene recombination in both datasets, and these have obscured the history within the genus. For S. ellipticum and S. pubescens, accessions from southern populations on ultramafic soils were genetically distinct from accessions from northern populations on non‐ultramafic soils. Given that no obvious morphological characters distinguish northern and southern populations in either taxon, both may be considered as examples of cryptic species. Incongruence between gene trees and species' delimitation may be explained by the parallel evolution of similar morphology, differential lineage sorting leading to differential fixation of alleles or different introgression patterns in the north and south leading to allele displacement. In New Caledonia, some species with broad ecological preferences may thus be artificial concepts. This suggests that they should be treated more critically in monographs and that the species' richness of the New Caledonian flora may be underestimated. Problems associated with the typification of S. ellipticum and evidence of hybridization events in the history of Spiraeanthemum are also discussed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161 , 137–152.  相似文献   

11.
From the ethyl acetate extract of the fresh roots of Angelica officinalis var. himaliaca, besides sitosterol, pregnenolone, peucenin-7-methyl ether, osthol and 18 furanocoumarins have been characterized by spectroscopic methods, including 13C NMR, and some chemical transformations.  相似文献   

12.
Non-cultivated N2-fixing indigenous legumes can be harnessed to enhance soil fertility replenishment of smallholder farms. Understanding N release patterns of biomass generated by such legumes is key in managing N availability to crops. Nitrogen and C mineralization patterns of indigenous legume species, mainly ofTephrosia andCrotalaria genera, and of soils sampled at termination of 1- and 2-year indigenous legume fallows (indifallows)were investigated in leaching tube incubations under laboratory conditions. With the exception ofTephrosia longipes Meisn (2.4%) andCrotalaria cylindrostachys Welw.ex Baker (1.8%), all indigenous legumes had >2.5% N. Total polyphenols and lignin were <4% and 15%, respectively, for all species.Crotalaria pallida (L.) andEriosema ellipticum Welw.ex Baker mineralized >50% of the added N in the first 30 days of incubation. Similar to mixed plant biomass from natural weed fallow,C. Cylindrostachys immobilized N during the 155-day incubation period. Indifallow fallow biomass reached peak N mineralization 55 days after most legumes had leveled off. Carbon release by legume species closely followedN release patterns,with mostCrotalaria species releasing >500 mg CO2-C kg?1 soil. Soils sampled at termination of fallows reached peak N mineralization in the first 21 days of incubation, with indifallows mineralizing significantly (P<0.05) more N than natural fallows. Application of mineral P fertilizer to indifallows and natural fallows increased C and N mineralization relative to control treatments. It was concluded that (i) indigenous legumes generate biomass of high quality within a single growing season, (ii) the slow N release of biomass generated under indifallow systems suggests that such fallows can potentially be manipulated to enhance N availability to crops, and (iii) N and C mineralization of organic materials in sandy soils is likely controlled by availability of P to the soil microbial pool.  相似文献   

13.
The ethanolic extract of the fresh roots of Heracleum canescens has afforded, besides sitosterol, osthol, methyl 3,4,5-trimethoxybenzoate and 11 furanocoumarins.  相似文献   

14.
A morphometric analysis of 18 attributes of 110 plants of theConospermum taxifolium complex suggests that it consists of three polythetically distinct taxa, corresponding to the traditional concepts ofC. taxifolium Smith s. str.,C. ericifolium Smith andC. ellipticum Smith. Discrimination is possible on the basis of leaf but not flower attributes. Analysis of allozymic variation indicates that the taxa are also genotypically differentiated.C. ericifolium andC. ellipticum are geographically isolated from each other but not fromC. taxifolium, andC. taxifolium is usually ecologically segregated from the other two taxa. Where this ecological segregation breaks down, morphological intermediates sometimes occur as the result of hybridization.  相似文献   

15.
Chemical investigation of an Assamese collection of Micromelum minutum gave four known coumarins (osthol, micromelin, murralongin and murrangatin) and five new coumarins, dihydromicromelin A and B, acetyldihydromicromelin A, the threo diastereomer of murrangatin, the 7,12-ether of 5,7-dihydroxy-3,6,8,4′-tetramethoxyfiavone and murrangatin.  相似文献   

16.
The size variability of the coccolith species Biscutum constans and Watznaueria barnesiae has been studied in 50 samples of the Late Albian “Niveau Breistroffer” black shales (Col de Palluel section, SE France). For each species, length and width of the total coccolith and the central unit have been measured in 60 specimens per sample. In addition, ellipticity and central unit length/total coccolith length ratio have been calculated. This study aims to improve our understanding of the taxonomic concepts of B. constans and W. barnesiae, and to test whether the size changes correspond to palaeoceanographic changes interpreted from other proxies. Two morphotypes (varieties) were differentiated for each of the two taxa studied. B. constans includes morphotypes with a narrow (B. constans var. constans) and a wide central unit (B. constans var. ellipticum). Between these two morphotypes no significant size differentiation has been observed. They seem to represent end members of a size continuum, relating to both the total coccolith- and central unit size distribution. The two morphotypes of W. barnesiae differ only in the absence (W. barnesiae var. barnesiae) and the presence of a narrow central opening (W. barnesiae var. fossacincta). No significant size differences have been observed between these two morphotypes, and both show similar distributions of the measured characteristics. We recommend that the studied morphotypes of both B. constans and W. barnesiae should not be assigned to different morphospecies. Throughout the studied black shale succession the measured parameters show mostly statistically insignificant, short-term fluctuations, but significant long-term trends have been observed for B. constans. These show a trend to smaller forms with a narrower central unit in the upper part of the succession. This change coincides with a cooling trend, as indicated by a nannofossil based temperature index. Therefore the two morphotypes of B. constans are interpreted to represent ecophenotypic varieties rather than two different morphospecies. No clear relationship has been recognized between the size of W. barnesiae and the palaeoenvironmental conditions.  相似文献   

17.
Dry forests are among the most diverse, yet threatened, communities in Hawai’i. Dry forests throughout the archipelago suffer from a lack of natural regeneration of trees. Two factors that may limit tree recruitment include poor seed dispersal and seed predation by rodents. Poor or limited dispersal of fleshy-fruited species results in seeds and fruits falling directly under parents. Dispersed and non-dispersed seeds may differ in their vulnerability to predation. We tested effects of seed location (under/away from parent trees) and pulp (presence/absence) on predation of four native species that suffer from limited dispersal and one readily-dispersed alien species in Kanaio Natural Area Reserve, Maui. Three natives (Diospyros sandwicensis, Pleomele auwahiensis, Santalum ellipticum), had significantly more seeds removed under parent trees than in exposed sites away from trees. For the one alien (Bocconia frutescens) and two native trees (D. sandwicensis, P. auwahiensis) that were evaluated, significantly more intact fruits were removed than were cleaned seeds. Presence of teeth marks and gnawed seed husk fragments indicate introduced rodents are destroying many of the seeds they remove. These results suggest that seed predation is disproportionately concentrated among poorly-dispersed seeds and may contribute to recruitment failure.  相似文献   

18.
Germination, establishment and growth of seedlings of tree speciesPalaquium ellipticum (primary),Actinodaphne malabarica (late secondary) andMacaranga peltata (early secondary) were studied in a humid tropical forest at Nelliampathy, in the Western Ghats of Kerala. While the primary species completed its germination within a brief period of 1.5 months, at the other extreme, early secondary species showed slow germination extending for about 5 months, the late secondary species falling in between. Although, all the species studied showed higher establishment and growth under gaps, the early secondary species were more responsive compared to the primary species. Primary species showed better establishment in undisturbed sites and natural gaps than under selection felled gaps; the reverse was true for late and early secondary species. Survival of seedlings increased with gap size, but sharply declined with gap age. Shoot/root ratio was consistently higher in the early secondary species than in the primary species.  相似文献   

19.
《Phytochemistry》1987,26(3):873-875
Two new quinolone alkaloids, reevesianine-A and -B, along with five known furoquinoline alkaloids, 7-isopentenyloxy-γ-fagarine, skimmianine, haplopine, evodine, evoxine, and nine known coumarins, 7-isopentenyloxy-8-isopentenylcoumarin, auraptene, osthol, isomeranzin, pranferin, R-(−)-columbianetin, umbelliferone, meranzin hydrate and skimmin, were isolated from the root and stem bark of Skimmia reevesiana collected in Taiwan. The structures of reevesianine-A and -B were established by chemical and spectroscopic methods.  相似文献   

20.
Osthol is an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson (Apiaceae), and has obvious therapeutic effect on fatty liver, but its mechanisms are not yet understood completely. One potential link between adipose tissue and fatty liver may be circulating fatty acids. In the present study, the effect of osthol on fatty acid synthesis and release in cultured 3T3-L1 adipocytes was observed. Following treatment of adipocytes with osthol, the intracellular levels of free fatty acids (FFA) and triacylglycerols as well as cultured supernatant level of FFA were decreased, and some lipogenic gene and protein expressions were also decreased, while the peroxisome proliferator-activated receptor (PPAR) α/γ mRNA expressions were increased. Osthol-reduced lipogenic gene expressions were decreased or abrogated after pretreatment with specific inhibitor(s) of PPARα and/or PPARγ.  相似文献   

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