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Thierry Acafou Yapi Jean Brice Boti Coffy Antoine Ahibo Ange Bighelli Vincent Castola Joseph Casanova Félix Tomi 《化学与生物多样性》2012,9(12):2802-2809
The chemical composition of 48 essential‐oil samples isolated from the leaves of Xylopia aethiopica harvested in six Ivoirian forests was investigated by GC‐FID and 13C‐NMR analyses. In total, 23 components accounting for 82.5–96.1% of the oil composition were identified. The composition was dominated by the monoterpene hydrocarbons β‐pinene (up to 61.1%) and α‐pinene (up to 18.6%) and the sesquiterpene hydrocarbon germacrene D (up to 28.7%). Hierarchical cluster and principal component analyses allowed the distinction of two groups on the basis of the β‐pinene and germacrene D contents. The chemical composition of the oils of Group I (38 oil samples) was clearly dominated by β‐pinene, while those of Group II (10 samples) were characterized by the association of β‐pinene and germacrene D. The leaves collected in the four inland forests produced β‐pinene‐rich oils (Group I), while the oil samples belonging to Group II were isolated from leaves harvested in forests located near the littoral. 相似文献
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Samuel A. Babarinde Yusuf A. Adeyemo 《Archives Of Phytopathology And Plant Protection》2013,46(8):810-816
The toxicity and repellency of Xylopia aethiopica seed extract was investigated in the laboratory against Tribolium castaneum Herbst. Concentration and days after treatment (DAT) caused a significant increase in T. castaneum adult mortality with an interaction effect of both on mortality when filter paper was impregnated with X. aethiopica extract. At 0.2 ml/60 cm2 extract, significant mortality was observed at three–seven DAT when compared with one DAT. At 0.4 ml/60cm2, 100% mortality was recorded at the lowest exposure period of one DAT. When 0.2 ml extract was applied to 5 g millet seeds, mortality at five–seven DAT was significantly higher than mortality observed in the control. Although repellency was dose-dependent, the percentage of T. castaneum that were repelled from treated filter paper was not significant. At 0.4 ml/60 cm2, Class II repellency (26.7%) was observed. The results suggest that X. aethiopica can only effectively control T. castaneum populations that have infested millet but do not prevent cross-infestation via repellency. 相似文献
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Identification of Phenanthrene Derivatives in Aerides rosea (Orchidaceae) Using the Combined Systems HPLC–ESI–HRMS/MS and HPLC–DAD–MS–SPE–UV–NMR 下载免费PDF全文
Veronika Cakova Aurélie Urbain Cyril Antheaume Nicole Rimlinger Patrick Wehrung Frédéric Bonté Annelise Lobstein 《Phytochemical analysis : PCA》2015,26(1):34-39
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HPLC‐UV and LC–MS Analyses of Acylquinic Acids in Geigeria alata (DC) Oliv. & Hiern. and their Contribution to Antioxidant and Antimicrobial Capacity 下载免费PDF全文
Dimitrina Zheleva‐Dimitrova Reneta Gevrenova Maya M. Zaharieva Hristo Najdenski Silviya Ruseva Valentin Lozanov Vessela Balabanova Sakina Yagi Georgi Momekov Vanio Mitev 《Phytochemical analysis : PCA》2017,28(3):176-184
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Comparison of Soxhlet,Accelerated Solvent and Supercritical Fluid Extraction Techniques for Volatile (GC–MS and GC/FID) and Phenolic Compounds (HPLC–ESI/MS/MS) from Lamiaceae Species 下载免费PDF全文
Raquel Rodríguez‐Solana José Manuel Salgado José Manuel Domínguez Sandra Cortés‐Diéguez 《Phytochemical analysis : PCA》2015,26(1):61-71
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Water Electrolysis: A Stable Graphitic,Nanocarbon‐Encapsulated,Cobalt‐Rich Core–Shell Electrocatalyst as an Oxygen Electrode in a Water Electrolyzer (Adv. Energy Mater. 14/2018) 下载免费PDF全文
Arumugam Sivanantham Pandian Ganesan Luis Estevez B. Peter McGrail Radha Kishan Motkuri Sangaraju Shanmugam 《Liver Transplantation》2018,8(14)
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A test of the central–marginal hypothesis using population genetics and ecological niche modelling in an endemic salamander (Ambystoma barbouri) 下载免费PDF全文
The central–marginal hypothesis (CMH) predicts that population size, genetic diversity and genetic connectivity are highest at the core and decrease near the edges of species' geographic distributions. We provide a test of the CMH using three replicated core‐to‐edge transects that encompass nearly the entire geographic range of the endemic streamside salamander (Ambystoma barbouri). We confirmed that the mapped core of the distribution was the most suitable habitat using ecological niche modelling (ENM) and via genetic estimates of effective population sizes. As predicted by the CMH, we found statistical support for decreased genetic diversity, effective population size and genetic connectivity from core to edge in western and northern transects, yet not along a southern transect. Based on our niche model, habitat suitability is lower towards the southern range edge, presumably leading to conflicting core‐to‐edge genetic patterns. These results suggest that multiple processes may influence a species' distribution based on the heterogeneity of habitat across a species' range and that replicated sampling may be needed to accurately test the CMH. Our work also emphasizes the importance of identifying the geographic range core with methods other than using the Euclidean centre on a map, which may help to explain discrepancies among other empirical tests of the CMH. Assessing core‐to‐edge population genetic patterns across an entire species' range accompanied with ENM can inform our general understanding of the mechanisms leading to species' geographic range limits. 相似文献
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Late Cretaceous–Early Eocene origin of yams (Dioscorea,Dioscoreaceae) in the Laurasian Palaearctic and their subsequent Oligocene–Miocene diversification 下载免费PDF全文
Juan Viruel José Gabriel Segarra‐Moragues Lauren Raz Félix Forest Paul Wilkin Isabel Sanmartín Pilar Catalán 《Journal of Biogeography》2016,43(4):750-762
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Dieter Seebach Simone Maschauer Olaf Prante Harald Hübner Peter Gmeiner Beata Kolesinska Renzo Cescato Beatrice Waser Jean Claude Reubi 《化学与生物多样性》2013,10(12):2101-2121
Neurotensin(8–13) (NTS(8–13)) analogs with C‐ and/or N‐terminal β‐amino acid residues and three DOTA derivatives thereof have been synthesized (i.e., 1 – 6 ). A virtual docking experiment showed almost perfect fit of one of the 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) derivatives, 6a , into a crystallographically identified receptor NTSR1 (Fig. 1). The affinities for the receptors of the NTS analogs and derivatives are low, when determined with cell‐membrane homogenates, while, with NTSR1‐exhibiting cancer tissues, affinities in the single‐digit nanomolar range can be observed (Table 2). Most of the β‐amino acid‐containing NTS(8–13) analogs (Table 1 and Fig. 2), including the 68Ga complexes of the DOTA‐substituted ones ( 6 ; Figs. 2 and 5), are stable for ca. 1 h in human serum and plasma, and in murine plasma. The biodistributions of two 68Ga complexes (of 6a and 6b ) in HT29 tumor‐bearing nude mice, in the absence and in the presence of a blocking compound, after 10, 30, and 60 min (Figs. 3 and 4) lead to the conclusion that the amount of specifically bound radioligand is rather low. This was confirmed by PET‐imaging experiments with the tumor‐bearing mice (Fig. 6). Comparison of the in vitro plasma stability (after 1 h) with the ex vivo blood content (after 10–15 min) of the two 68Ga complexes shows that they are rapidly cleaved in the animals (Fig. 5). 相似文献
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Cong‐Li Xu Tao Su Jian Huang Yong‐Jiang Huang Shu‐Feng Li Yi‐Shan Zhao Zhe‐Kun Zhou 《植物分类学报:英文版》2019,57(2):169-179
The uplift of the Qinghai–Tibetan Plateau dramatically changed the regional topography and climate, profoundly impacting the distribution of many plant lineages. Plant responses to environmental changes are particularly prominent in lineages that require ecological factors differentiated from those present before the uplift of the QTP. Two fossil occurrences of Christella H. Lév., Fl. Kouy–Tchéou (Thelypteridaceae), a fern genus now distributed mainly at low elevations of the pantropics with warm and moist habitats, are described based on fossilized Cenozoic leaf fronds recovered from SW China: late Paleocene Christella nervosa (J. R. Tao) C. L. Xu, T. Su & Z. K. Zhou comb. nov. found in Liuqu, southern Tibet and middle Miocene Christella sp. recovered from the Jinggu Basin in western Yunnan. The frond fossils from both sites share key morphological characteristics that diagnose these fossils as Christella. After detailed comparisons, we further clarified Christella papilio (C. Hope) Holttum, a species distributed in warm, humid habitats at altitudes no more than 1300?m, as the nearest living relative of C. nervosa. This finding suggested that southern Tibet had not reached its present elevation during the late Paleocene (ca. 56 Ma). We propose that the uplift, accompanied by severe cooling and aridification after the late Paleocene, caused the disappearance of Christella in southern Tibet, whereas paleoenvironmental conditions enabled the genus to survive in Yunnan. Our study provides the first example of distributional constraints of ferns in SW China in response to paleoenvironmental changes in the Qinghai–Tibetan Plateau and nearby areas. 相似文献
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Thompson 《Journal of evolutionary biology》1999,12(1):38-48
The developmental origin of phenotypic plasticity in morphological shape can be attributed to environment-specific changes in growth of overall body size, localized growth of a morphological structure or a combination of both. I monitored morphological development in the first four nymphal instars of grasshoppers (Melanoplus femurrubrum) raised on two different plant diets to determine the ontogenetic origins of diet-induced phenotypic plasticity and to quantify genetic variation for phenotypic plasticity. I measured diet-induced phenotypic plasticity in body size (tibia length), head size (articular width and mandible depth) and head shape (residual articular width and residual mandible depth) for grasshoppers from 37 full-sib families raised on either a hard plant diet (Lolium perenne) or a soft plant diet (Trifolium repens). By the second to third nymphal instar, grasshoppers raised on a hard plant diet had significantly smaller mean tibia length and greater mean residual articular width (distance between mandibles adjusted for body size) compared with full-sibs raised on a soft plant diet. However, there was no significant phenotypic plasticity in mean unadjusted articular width and mandible depth, and in mean residual mandible depth. At the population level, development of diet-induced phenotypic plasticity in grasshopper head shape is mediated by plastic changes in allocation to tissue growth that maintain growth of head size on hard, low-nutrient diets while reducing growth of body size. Within the population, there was substantial variation in the plasticity of growth trajectories since different full-sib families developed phenotypic plasticity of residual articular width through different combinations of head and body size growth. Genetic variation for diet-induced phenotypic plasticity of residual articular width, residual mandible depth and tibia length, as estimated by genotype–environment interaction, exhibited significant fluctuation through ontogeny (repeated measures MANOVA , family × plant × instar, P < 0.01). For example, there was significant genetic variation for phenotypic plasticity of residual articular width in the third nymphal instar, but not earlier or later in ontogeny. The observed patterns of genetic variation are discussed with reference to short-term constraints and the evolution of phenotypic plasticity. 相似文献
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V. Georgantas N. Kotsakis C.P. Raptopoulou A. Terzis L. Iordanidis M. Zervou T. Jakusch T. Kiss A. Salifoglou 《Journal of inorganic biochemistry》2009,103(11):1530-1541
Efforts to delineate the interactions of neurotoxic Al(III) with low molecular mass substrates relevant to neurodegenerative processes, led to the investigation of the pH-specific synthetic chemistry of the binary Al(III)-[N-(phosphonomethyl) iminodiacetic acid] (Al-NTAP), Al(III)-[nitrilo-tris(methylene-phosphonic acid)] (Al-NTA3P), and Al(III)-[1-hydroxy ethylidene-1,1-diphosphonic acid] (Al-HEDP) systems, in correlation with solution speciation studies. Reaction of Al(NO3)3·9H2O with NTAP at pH 7.0 and 4.0 afforded the new species (CH6N3)4[Al2(C5H6NPO7)2(OH)2]·8H2O (1) and (NH4)2[Al2(C5H6NPO7)2(H2O)2]·4H2O (2), while reaction of Al(NO3)3·9H2O with NTA3P led to K8[Al2(C3H6NP3O9)2(OH)2]·20H2O (3). Complexes 1–3 were characterized by elemental analysis, FT-IR, 13C, 31P, 1H NMR (for 1–2 solid state and solution NMR where feasible), and X-ray crystallography. The structures of 1–3 reveal the presence of uniquely defined dinuclear complexes of octahedral Al(III) bound to fully deprotonated phosphonate ligands, water and hydroxo moieties. The aqueous solution speciation studies on the aforementioned binary systems project a clear picture of the binary Al(III)–(carboxy)phosphonate interactions and species under variable pH-conditions and specific Al(III):ligand stoichiometry. The concurrent solid state and solution work (a) exemplifies essential structural and chemical attributes of soluble aqueous species, reflecting well-defined interactions of Al(III) with phosphosubstrates and (b) strengthens the potential linkage of neurotoxic Al(III) chemical reactivity toward O,N-containing (carboxy)phosphate-rich cellular targets. 相似文献