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131.
Comparison of Polyphenol Profile and Antimutagenic and Antioxidant Activities in Two Species Used as Source of Solidaginis herba – Goldenrod
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Dorota Woźniak Sylwester Ślusarczyk Krzysztof Domaradzki Andrzej Dryś Adam Matkowski 《化学与生物多样性》2018,15(4)
European Pharmacopoeia accepts two equivalent species Solidago canadensis L. and S. gigantea Aiton as goldenrod (Solidaginis herba). We compared phytochemical profile of both species from invasive populations in Poland. Further, we compared in vitro antimutagenic and antioxidant activities of solvent extracts from aerial (AP) and underground parts (UP). In S. gigantea, flavonoid profile was dominated by quercetin glycosides, with quercitrin as the major compound. In S. canadensis, quercetin and kaempferol rutinosides were two major constituents. Caffeoylquinic acids (CQAs) were less diverse with 5‐CQA as a main compound. In UP, over 20 putative diterpenoids were detected, mostly unidentified. Several CQAs were present in higher amounts than in AP. Antioxidant and antimutagenic activities were different between species and organs, with the strongest inhibition of lipid peroxidation by Et2O and AcOEt fractions from AP of both species (IC50 13.33 – 16.89 μg/mL) and BuOH fraction from S. gigantea UP (IC50 = 13.32 μg/mL). Chemical mutagenesis was completely inhibited by non‐polar fractions, but oxidative mutagenesis was inhibited up to 35% only by S. canadensis. No clear relationship was found between chemical profiles and antimutagenic activity. In conclusion, both species have diverse activity and their phytochemical profiles should be considered in quality evaluation. UP of these weeds can also provide potential chemopreventive substances for further studies. 相似文献
132.
Mapping of quantitative trait loci for tuber starch and leaf sucrose contents in diploid potato 总被引:1,自引:0,他引:1
133.
134.
The effect of choline, acetylcholine, carbamylcholine and of the acetylcholinesterase inhibitors, eserine and neostigmine,
on the germination of seeds exhibiting different photosenitivities was studied in two light variants. Both in the darkness
and in continuous white light the substances in question had no effect or only slightly modified germination of photoblastically
neutral seeds. On the other hand, the above substances, particularly aeetylcholine and carbamylcholine, stimulated germination
of photoblastically positive seeds, and inhibited germination of photoblastically negative seeds in continuous white light. 相似文献
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136.
JAMES A. ROBERTSON ADAM ŚLIPIŃSKI KEVIN HIATT KELLY B. MILLER MICHAEL F. WHITING JOSEPH V. MCHUGH 《Systematic Entomology》2013,38(1):209-232
Eight genes (nuclear: 18S, 28S, H3, CAD; mitochondrial: 12S, 16S, COI, COII) and morphology were used to infer the evolutionary history of Corylophidae, some of the smallest free‐living insects. The study included 36 corylophid exemplars, representing approximately 60% of the known generic diversity of the family and 16 cucujoid outgroup taxa. Multiple partitioning strategies, molecular datasets, combined datasets and different taxon sampling regimes using maximum likelihood and mixed‐model Bayesian inference were utilized to analyse these data. Most results were highly concordant across analyses. There was strong agreement across (i) partitioning strategies, (ii) maximum likelihood and Bayesian inference analyses of the molecular data, and (iii) Bayesian inference of the molecular data alone and Bayesian inference of the combined morphological and molecular data when all terminal taxa were included. When a strict taxon sampling protocol was employed so that only single generic exemplars were included, deep relationships were affected in the resulting phylogenetic hypotheses. Under such narrow sampling strategies, deep phylogenetic relationships were also sensitive to the choice of generic exemplars. Although it is often challenging to obtain single representatives for many taxa in higher‐level phylogenetic analyses, these results indicate the importance of using denser taxon sampling approaches even at the specific level for genera included in such studies. Molecular data alone support Anamorphinae (Endomychidae) strongly as the sister group of Corylophidae. In combined data analyses, Coccinellidae is recovered as the sister group to Corylophidae. In all analyses, Corylophidae and the subfamily Corylophinae are recovered as monophyletic. The monophyly of Periptyctinae was untested, as only a single species was included. All included corylophine tribes were recovered as monophyletic with the exception of Aenigmaticini; Aenigmaticum Matthews forms the sister group to Orthoperus Stephens and Stanus?lipiński et al. is recovered as the sister group of Sericoderus Stephens. Stanus tasmanicus?lipiński et al. is transferred to a new genus, Pseudostanus Robertson, ?lipiński & McHugh gen.n. incertae sedis. We propose a new tribe, Stanini Robertson, ?lipiński & McHugh trib.n. for Stanus bowesteadi?lipiński et al. and a new concept of Aenigmaticini sensu.n. to include only the nominate genus. Anatomical transitions associated with corylophid miniaturization are highlighted. Key phenotypic modifications and elevated rates of substitution in nuclear rRNA genes are evident in a subgroup of Corylophinae that includes the most diminutive species. Other taxonomic and evolutionary implications are discussed in light of the results. 相似文献
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138.
Flowers of Calendula officinalis were incubated with mevalonic acid doubly labelled with 14C in position 2 and 3H in positions 2R, 2S, 4R or 5R,S and the [3H/14C] ratios determined in squalene β-sitosterol, stigmasterol, Δ7-sterols and stigmastan-3 β-ol. The results indicated that in the biosynthesis of these sterols: formation of the Δ7 double bond is associated with elimination of hydrogen from the 7β position, formation of the Δ5 double bond with elimination of hydrogens from the 5 and 6α positions, and formation of the Δ22 double bond with elimination of the 22-pro-S and 23 hydrogens. Demethylation in position 4 is associated with elimination of hydrogen from the 3α position whereas demethylation in position 14 occurs without hydrogen loss from position 15. Alkylation in position 24 is associated with hydrogen elimination from this position. 相似文献
139.
Magdalena Kroc Grzegorz Koczyk Wojciech Święcicki Andrzej Kilian Matthew N. Nelson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(5):1237-1249
Key message
This is the first clear evidence of duplication and/or triplication of large chromosomal regions in a genome of a Genistoid legume, the most basal clade of Papilionoid legumes.Abstract
Lupinus angustifolius L. (narrow-leafed lupin) is the most widely cultivated species of Genistoid legume, grown for its high-protein grain. As a member of this most basal clade of Papilionoid legumes, L. angustifolius serves as a useful model for exploring legume genome evolution. Here, we report an improved reference genetic map of L. angustifolius comprising 1207 loci, including 299 newly developed Diversity Arrays Technology markers and 54 new gene-based PCR markers. A comparison between the L. angustifolius and Medicago truncatula genomes was performed using 394 sequence-tagged site markers acting as bridging points between the two genomes. The improved L. angustifolius genetic map, the updated M. truncatula genome assembly and the increased number of bridging points between the genomes together substantially enhanced the resolution of synteny and chromosomal colinearity between these genomes compared to previous reports. While a high degree of syntenic fragmentation was observed that was consistent with the large evolutionary distance between the L. angustifolius and M. truncatula genomes, there were striking examples of conserved colinearity of loci between these genomes. Compelling evidence was found of large-scale duplication and/or triplication in the L. angustifolius genome, consistent with one or more ancestral polyploidy events. 相似文献140.
Katarzyna Wiśniewska Anna Piórkowska Joanna Kasprzyk Marek Bronk Krystyna Świeć 《Folia microbiologica》2014,59(6):465-471
Staphylococcus aureus is a leading cause of bloodstream infections (BSI) and diseases that may be caused by hematogenous spread. The staphylococcal adhesin, for which the association with the infections emerging as a complication of septicemia has been well documented, is a bone sialoprotein-binding protein (Bbp). The aim of the study was to assess the prevalence of a bbp gene in S. aureus bloodstream isolates associated with BSI and to investigate to what degree the distribution of this gene is linked to the clonality of the population. Spa typing, used in order to explore the genetic population structure of the isolates, yielded 29 types. Six spa clusters and seven singletons were identified. The most frequent was spa clonal complex CC021 associated with MLST CC30 (38 %). The bbp gene was found in 47 % of isolates. Almost all isolates (95 %) clustered in spa clonal complex CC021 were positive for this gene. All isolates carrying the bbp gene were sensitive to methicillin, and if clustered in the spa CC021, belonged to agr group III. Our study shows that Bbp is not strictly associated with BSI. However, one may conclude that for clonally related S. aureus strains most commonly causing BSI, the risk of Bbp-mediated complications of septicemia is expected to be higher than for other strains. 相似文献