Search results for "compounds"
showing 10 items of 3372 documents
Halloysite nanotubes loaded with peppermint essential oil as filler for functional biopolymer film
2016
Abstract The purpose of this paper is to show how a functional bionanocomposite film with both antioxidant and antimicrobial activities was successfully prepared by the filling of a pectin matrix with modified Halloysite nanotubes (HNT) containing the essential peppermint oil (PO). Firstly, HNT surfaces were functionalized with cucurbit[6]uril (CB[6]) molecules with the aim to enhance the affinity of the nanofiller towards PO, which was estimated by means of HPLC experiments. The HNT/CB[6] hybrid was characterized by several methods (thermogravimetry, FT-IR spectroscopy and scanning electron microscopy) highlighting the influence of the supramolecular interactions on the composition, therma…
Effects of thrombin and of the phospholipase C inhibitor, D609, on the vascularity of the chick chorioallantoic membrane.
2000
Abstract Microvascular corrosion casting was used to assess the effects of thrombin and D609, a phospholipase C inhibitor, on the vascularity of the chick embryo chorioallantoic membrane (CAM). Discs containing vehicle, thrombin or D609 were placed on the CAM of fertilized white Leghorn eggs on Day 9 of gestation and vascularity was assessed on Day 11. Thrombin caused significant increases in the numbers (43%), diameters (5%) and lengths (17%), of both pre- and postcapillaries (first-order vessels by centripetal ordering). Conversely, D609 caused a decrease in the numbers (27%), lengths (12%) and diameters (8%) of first-order vessels. D609 decreased the total vascular volume of first- to th…
Improving sensitivity in simultaneous determination of copper carboxylates by nonaqueous capillary electrophoresis
2005
Abstract A new method of nonaqueous capillary electrophoresis (NACE) with UV spectrophotometric detection was developed and optimized for the simultaneous determination of seven carboxylates (trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CDTA), diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediamine-N,N′,N′-triacetic acid (HEDTA), nitrilotriacetic acid (NTA), 1,3-diaminopropane-N,N,N′,N′-tetraacetic acid (PDTA) and triethylenetetraaminehexaacetic acid (TTHA)) as copper complexes. The method development was carried out by using a fused silica capillary. Background electrolyte (BGE) was optimized and the best separation a…
Vanadium pentoxide nanoparticles mimic vanadium haloperoxidases and thwart biofilm formation
2012
Marine biofouling—the colonization of small marine microorganisms on surfaces that are directly exposed to seawater, such as ships' hulls—is an expensive problem that is currently without an environmentally compatible solution1. Biofouling leads to increased hydrodynamic drag, which, in turn, causes increased fuel consumption and greenhouse gas emissions. Tributyltin-free antifouling coatings and paints1, 2, 3, 4 based on metal complexes or biocides have been shown to efficiently prevent marine biofouling. However, these materials can damage5 the environment through metal leaching (for example, of copper and zinc)6 and bacteria resistance7. Here, we show that vanadium pentoxide nanowires ac…
Panniculitis due to potassium bromide.
1998
Potassium bromide again is well known to be surprisingly effective in patients with severe myoclonic epilepsy in infants (SME). Rare side effects on the skin reappeared, such as the febrile nodular panniculitis (Weber-Christian syndrome). In 1993 we described the first three cases of necrotizing panniculitis and introduced the term 'halogen panniculitis'. It is a systemic disease with crops of subcutaneous nodules, fever, elevated sedimentation rate, hepatosplenomegalia, and abdominal pain. Later severe necrosis of the skin and adipose tissue may happen with deep ulcerations. History and course of five cases, described in this paper, suggest either an allergy or toxic reason. Histologic pic…
Evaluating equilibrium and non-equilibrium transport of bromide and isoproturon in disturbed and undisturbed soil columns.
2007
19 pages; International audience; In this study, displacement experiments of isoproturon were conducted in disturbed and undisturbed columns of a silty clay loam soil under similar rainfall intensities. Solute transport occurred under saturated conditions in the undisturbed soil and under unsaturated conditions in the sieved soil because of a greater bulk density of the compacted undisturbed soil compared to the sieved soil. The objective of this work was to determine transport characteristics of isoproturon relative to bromide tracer. Triplicate column experiments were performed with sieved (structure partially destroyed to simulate conventional tillage) and undisturbed (structure preserve…
Ageing of Dissolved Halogenated Humic Substances and the Microbiological Influence on this Process
2000
The distribution of halogens in various fractions of humic substances (HS), separated by their molecular weight, was found to be different for the different halogens. This was demonstrated for chlorine, bromine, and iodine in sewage and brown water samples by applying inductively coupled plasma mass spectrometry coupled with size-exclusion chromatography. Quantification of the different fractions of iodinated humic substances was obtained by quadrupole mass spectrometry in connection with the isotope dilution technique using an 129I-enriched spike solution. Quantitative analysis was not possible for the corresponding chlorine and bromine species because of spectrometric interferences in the…
XAFS Studies of High-Valent Porphyrinato Manganèse Complexes with Ozone
1997
We produce strong evidence of the interaction of ozone with a series of Manganese (III) porphyrinato complexes to form a well defined reactive intermediate. In the latter species, the Manganese atom which is formally in a tetravalent (IV) state, is (at least) hexacoordinated with the metal unambiguously lying in the basal plane of the four pyrrolic nitrogens of the porphyrin macrocycle. Substitution of Bromine or Chlorine axial ligands by ozonids is most likely to happen. This conclusion is also supported by XANES and EXAFS spectra recorded at the Chlorine K-edge which suggest that ozone may even form with chlorine a complex anion.
The role of plant volatiles in prediction of floral resource suitability: chemical ecology to enhance conservation biological control.
2015
Plants emit substantial amounts of volatile organic compounds (VOCs) which represent a decisive communication channel, governing essential decisions insect have to make, such as choice of food. Understanding these interactions is critically important in Habitat Management and in a broader view in Conservation Biological Control. Suitable flower species must enhance the survival and fecundity of natural enemies but in addition they also need to be highly attractive and thus frequently visited. To date few examples exist that have considered both criteria. In this study we tested the effects of the flowering plants alyssum (Lobularia maritima), buckwheat (Fagopyrum esculentum), French marigol…
Insect-associated bacteria assemble the antifungal butenolide gladiofungin by non-canonical polyketide chain termination
2020
Abstract Genome mining of one of the protective symbionts (Burkholderia gladioli) of the invasive beetle Lagria villosa revealed a cryptic gene cluster that codes for the biosynthesis of a novel antifungal polyketide with a glutarimide pharmacophore. Targeted gene inactivation, metabolic profiling, and bioassays led to the discovery of the gladiofungins as previously‐overlooked components of the antimicrobial armory of the beetle symbiont, which are highly active against the entomopathogenic fungus Purpureocillium lilacinum. By mutational analyses, isotope labeling, and computational analyses of the modular polyketide synthase, we found that the rare butenolide moiety of gladiofungins deriv…