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Mariangela Marrelli Filomena Conforti Carmen Formisano Nelly Apostolides Arnold Francesco Menichini 《Natural product research》2016,30(6):735-739
The essential oils from Origanum dictamnus, Origanum libanoticum and Origanum microphyllum were analysed by GC-MS, finding carvacrol, p-cymene, linalool, γ-terpinene and terpinen-4-ol as major components. The antioxidant activity by the DPPH and FRAP tests and the antiproliferative activity against two human cancer cell lines, LoVo and HepG2, were investigated, showing that the essential oil of O. dictamnus was statistically the most inhibitory on both the cell lines, while all the oils exerted a weak antioxidant activity. Furthermore, the samples were tested against 10 Gram-negative and Gram-positive bacteria; all the oils were active on Gram-positive bacteria but O. dictamnus essential oil was the most effective (MIC = 25–50 μg/mL), showing also a good activity against the Gram-negative Escherichia coli (MIC = 50 μg/mL). Data suggest that these essential oils and particularly O. dictamnus oil could be used as valuable new flavours with functional properties for food or nutraceutical products. 相似文献
94.
A variety of techniques exist that provide chemical information in the form of a spatially resolved image: electron microprobe
analysis, nuclear microprobe analysis, synchrotron radiation microprobe analysis, secondary ion mass spectrometry, and confocal
fluorescence microscopy. Linear (LINAC) and circular (synchrotrons) particle accelerators have been constructed worldwide
to provide to the scientific community unprecedented analytical performances. Now, these facilities match at least one of
the three analytical features required for the biological field: (1) a sufficient spatial resolution for single cell (< 1 μm)
or tissue (<1 mm) analyses, (2) a temporal resolution to follow molecular dynamics, and (3) a sensitivity in the micromolar
to nanomolar range, thus allowing true investigations on biological dynamics. Third-generation synchrotrons now offer the
opportunity of bioanalytical measurements at nanometer resolutions with incredible sensitivity. Linear accelerators are more
specialized in their physical features but may exceed synchrotron performances. All these techniques have become irreplaceable
tools for developing knowledge in biology. This review highlights the pros and cons of the most popular techniques that have
been implemented on accelerator-based sources to address analytical issues on biological specimens.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
95.
Singh AK Pedro LG Gomes FP Yano HM Auricchio MT Kedor-Hackmann ER Santoro MI 《Journal of AOAC International》2008,91(3):572-579
Sibutramine hydrochloride monohydrate, chemically 1-(4-chlorophenyl)-N,N-dimethyl-alpha-(2-methylpropyl) hydrochloride monohydrate (SB.HCI.H20), was approved by the U.S. Food and Drug Administration for the treatment of obesity. The objective of this study was to develop, validate, and compare methods using UV-derivative spectrophotometry (UVDS) and reversed-phase high-performance liquid chromatography (HPLC) for the determination of SB.HCI.H20 in pharmaceutical drug products. The UVDS and HPLC methods were found to be rapid, precise, and accurate. Statistically, there was no significant difference between the proposed UVDS and HPLC methods. The enantiomeric separation of SB was obtained on an alpha-1-acid glycoprotein column. The R- and S-sibutramine were eluted in < 5 min with baseline separation of the chromatographic peaks (alpha = 1.9 and resolution = 1.9). 相似文献
96.
Michael Keane 《Inventiones Mathematicae》1972,16(4):309-324
LetT be ann-to-1 covering transformation of the compact metric spaceX (e.g. (X, T) then-shift). For suitable functionsg onX an inverse
g ofT is defined:
g is a Markov kernel. Ifg is strictly positive and satisfies a Lipschitz condition, then there exists a unique
g measure, strongly mixing underT. Conversely, we associate to anyT-invariant probability measure a suitableg, and ifg is nice, then strong mixing is present. Examples include all Bernoulli and Markov measures on then-shift. The strong mixing criterion is useful, and applications to harmonic analysis, ergodic theory, and symbolic dynamics are given. For example: if
is any infinite subgroup of the group of roots of unity, there exist uncountably many (explicitly constructible) continuous Morse sequences whose corresponding dynamical systems are pairwise non-isomorphic and all have as eigenvalue group exactly the given group
.C.N.R.S. Équipe Associée 250.Research supported in part by NSF grant GP-16392 while the author was visiting at Yale University. 相似文献
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Simone Perna Manuela Biserni Filippo Borsani Martina Berardi Daniele Spadaccini Mariangela Rondanelli 《Natural product research》2020,34(17):2500-2504
AbstractThe aim of the study is to evaluate the effectiveness of of 4 and 8?week supplementation with highly standardized formula with Fraxinus ornus L., plus Ananas comosus L., concentrated juice, Betula pendula R., Equisetum arvense L., Urtica dioica L. and Pilosella officinarum L. Vail dry extract, on the state of hydration and bloating sensation in subjects with high and moderate extra cellular water (ECW). 19 women (mean age 35?yr and Body Mass Index 22.82?kg\m2) with Extra Cellular Water over 45%completed the study and their data were analysed at baseline, at 30 and 60?days. Bio-impedance, SF36 and anthropometric parameters were assessed. The ECW decreased of ?1.97% (at 30?days) and ?2.30% (60?days) (p?<?0.01). Also fat mass decreased of ?1.58% (at 30?days) and ?2.21% (60?days) (p?=?0.057). An improvement of free fat mass was assessed (p?<?0.05) but not on bloating sensation questionnaire at 60?days (p?=?0.422). 相似文献
100.
Coppola C Paciello A Mangiapia G Licen S Boccalon M De Napoli L Paduano L Tecilla P Montesarchio D 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(46):13757-13772
A novel fluorescently labelled synthetic ionophore, based on a cyclic phosphate-linked disaccharide (CyPLOS) backbone and decorated with four tetraethylene glycol tails carrying dansyl units, has been synthesised in 12 steps in 26% overall yield. The key intermediate in the synthetic strategy is a novel glucoside building block, serving through its 2- and 3-hydroxy groups as the anchor point for flexible tetraethylene glycol tentacles with reactive azido moieties at their ends. To test the versatility of this glucoside scaffold, it was preliminarily functionalised with a set of diverse probes--as fluorescent, redox-active or hydrophobic tags--either by reduction of the azides followed by condensation with activated carboxylic acid derivatives, or by a direct coupling with a terminal alkyne in a Cu(I)-promoted 1,3-dipolar cycloaddition. Tagging of the monomeric building block with dansyl residues allowed us to prepare a fluorescent, amphiphilic macrocycle, which was investigated for its propensity to self-aggregate in CDCl(3)--studied by means of concentration-dependent (31)P NMR spectroscopy experiments--and in aqueous solution, in which combined dynamic light scattering (DLS) and small-angle neutron scattering (SANS) measurements provided a detailed physico-chemical analysis of the self-assembled systems, mainly organised in the form of large vesicles. Its ion-transport properties through phospholipid bilayers, determined by HPTS fluorescence assays, showed this compound to be more active than the previously synthesised CyPLOS congeners. Solvent-dependent fluorescence changes for the labelled ionophore in liposome suspension established that the dansyl moieties are dispersed in environments with polarity intermediate between those of CH(2)Cl(2) and propan-2-ol, suggesting that the CyPLOS tentacles infiltrate the mid-polar region of the membranes. 相似文献