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1.
Fabiana Quaglia Giuseppe Fusco Giuseppe De Rosa Francesca Ungaro Agnese Miro Maria Immacolata La Rotonda 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):669-674
The aim of this work was to produce lycopene-containing powders from tomato products by a solvent-free method making use of
β-cyclodextrin (βCD). Powders were prepared by spray-drying a tomato concentrate (TC), one of the most bioavailable form of
lycopene, after mechanical treatment with βCD in different weight ratios. The obtained product was centrifuged to eliminate
partly food matrix and characterized for the amount of lycopene hydrodispersed/hydrosolubilized in the aqueous fraction. The
chemical antioxidant activity of sera was evaluated too. Powders obtained by spray-drying sera exhibited good flow properties,
a lycopene content between 0.4 and 1.09 mg/g and excellent water dispersability. The process developed, which makes use of
βCD for the treatment of tomato products, turns to be of great interest to obtain a bulk material for nutraceuticals displaying
superior biovailability of lycopene. 相似文献
2.
Francesco Ghetti Giuliano Colombetti Francesco Lenci Enzo Campani Erseo Polacco Maurizio Quaglia 《Photochemistry and photobiology》1985,42(1):29-33
Abstract— The spectroscopic characterization of the photoreceptor pigment is one of the main questions in the study of the photosensory transduction chains in photomotile microorganisms. One of the possible techniques that can be used is in vivo microspectrofluorometry. By means of a tunable dye-laser microspectrofiuorometer developed by us, we have investigated some of the spectroscopic properties of the photoreceptor pigment of the green flagellate Euglena gracilis. The in vivo fluorescence excitation spectrum has been determined and the fluorescence quantum yield has been measured. The results show that flavins are indeed present in the paraflagellar body of E. gracilis and that their fluorescence quantum yield is much lower than that of a free flavin. An estimate of the order of magnitude of the rate constants for primary molecular reactions is tentatively given. 相似文献
3.
Quaglia M Carazzone C Sabella S Colombo R Giorgetti S Bellotti V De Lorenzi E 《Electrophoresis》2005,26(21):4055-4063
Beta2-microglobulin (beta2-m) is a small amyloidogenic protein normally present on the surface of most nucleated cells and responsible for dialysis-related amyloidosis, which represents a severe complication of long-term hemodialysis. A therapeutic approach for this amyloidosis could be based on the stabilization of beta2-m through the binding to a small molecule, and consequent inhibition of protein misfolding and amyloid fibril formation. A few compounds have been described to weakly bind beta2-m, including the drug suramin. The lack of a binding site for nonpolypeptidic ligands on the beta2-m structure makes it difficult for both the identification of functional groups responsible for the binding and the search of hits to be optimized. The characterization of the binding properties of suramin for beta2-m by using three different techniques (surface plasmon resonance, affinity CE (ACE), ultrafiltration) is here described and the results obtained are compared. The common features of the chemical structures of the compounds known to bind the protein led us to select 200 sulfonated/suramin-like molecules from a wider chemical library on the basis of similarity rules, so as to possibly single out some interesting hits and to gain more information on the functional groups involved in the binding. The development of screening methods to test the compounds by using ultrafiltration and ACE is described. 相似文献
4.
M.?B.?BarbaroEmail author R.?Cenni A.?Molinari M.?R.?Quaglia 《The European Physical Journal A - Hadrons and Nuclei》2004,22(3):377-390
We address the problem of two pairs of fermions living on an arbitrary number of single-particle levels of a potential well (mean field) and interacting through a pairing force in the framework of the Richardson equations. The associated solutions are classified in terms of a number vl, which reduces to the seniority v in the limit of a large pairing strength G and yields the number of pairs not developing a collective behaviour, their energy remaining finite in the G limit. We express analytically, through the moments of the single-particle levels distribution, the collective mode energy and the two critical values Gcr+ and Gcr- of the coupling which can exist on a single-particle level with no pair degeneracy. Notably Gcr+ and Gcr-, when the number of single particle levels goes to infinity, merge into the critical coupling of a one-pair system Gcr (when it exists), which is not envisioned by the Richardson theory. In correspondence of Gcr, the system undergoes a transition from a mean-field- to a pairing-dominated regime. We finally explore the behaviour of the excitation energies, wave functions and pair transfer amplitudes versus G finding out that the former, for G > Gcr-, come close to the BCS predictions, whereas the latter display a divergence at Gcr, signaling the onset of a long-range off-diagonal order in the system. 相似文献
5.
6.
G. Del Fiore J. M. Peters L. Quaglia F. Boudjelida M. C. Pardon J. L. Piette R. Cantineau Ch. De Landsheere P. Rigo 《Journal of Radioanalytical and Nuclear Chemistry》1986,104(5):301-315
An automated continuous flow process has been developed for the synthesis of11C-ethanol and11C-butanol. These alcohols were synthesized via the same route. The reaction of11CO2 with methylmagnesium bromide or with n-propylmagnesium chloride, followed by a lithium aluminum hydride reduction and hydrolysis produced respectively11C-ethanol and11C-butanol. Preparation can be completed in 25 min. In each case the radiochemical purity, as determined by high pressure liquid chromatography /HPLC/ was greater than 98%. Biological quality control shows that the products are suitable for human use. The process has been completely automated to limit radiation exposure to personnel, reduce preparation time, and increase reproducibility. 相似文献
7.
W.D. Apel J. Ausländer H. Müller G. Sigurdsson H.M. Staudenmaier U. Stier E. Bertolucci I. Mannelli G. Perazzini M. Quaglia P. Rehak A. Scribano F. Sergiampietri M.L. Vincelli 《Physics letters. [Part B]》1975,55(1):111-116
Results are given for the production differential cross sections and the ω decay angular distribution in terms of the ω spin density matrix elements. 相似文献
8.
W.D. Apel K.H. Augenstein E. Bertolucci S.V. Donskov A.V. Inyakin V.A. Kachanov R.N. Krasnokutsky M. Kruger G. Leder A.A. Lednev I. Mannelli Yu.V. Mikhailov H. Müller G.M. Pierazzini Yu.D. Prokoshkin M. Quaglia H. Schneider A. Scribano M.L. Vincelli 《Physics letters. [Part B]》1978,72(4):500-502
The invariant mass spectrum of neutral final states produced in π?p charge-exchange scattering at 40 GeV/c has been studied, searching for heavy particles decaying in 2γ. A peak is observed around 2.85 GeV/c2. The cross section of the reaction π?p→X(2.85)+n, times the branching ratio of the X→2γ decay, is measured to be . 相似文献
9.
Francesco Barbato Maria Immacolata La Rotonda Agnese Miro Patrizia Morrica Fabiana Quaglia 《Journal of inclusion phenomena and macrocyclic chemistry》2000,38(1-4):423-433
This study was carried out with the aim ofinvestigating the interactions between-cyclodextrin and carbaryl, a carbamatepesticide, and their effect on some physico-chemicalproperties of carbaryl, such as aqueous solubility andlipophilicity. The interactions between carbaryl and-cyclodextrin were thoroughly investigated bothin solution and in the solid state. The effect of-cyclodextrin on the aqueous solubility ofcarbaryl was evaluated by the phase solubility method.The amount of carbaryl dissolved increased linearlywith the addition of -cyclodextrin according toan AL type plot and without precipitation of thecomplex. The apparent stability constant of thecomplex was 289 ± 21 M-1, assuming a 1 : 1stoichiometry; this value was confirmed by a methodbased on circular dichroism measurements.Equimolar carbaryl/-cyclodextrin solid systemswere prepared by physical-mixing and freeze-drying,and fully characterised by Differential ScanningCalorimetry, X-ray powder diffractometry and FourierTransform Infra-Red analysis. The results of the solidstate study demonstrated that the freeze-drying methodyields a system with a high degree of amorphisationand yields an inclusion complex.The dissolution profile of the pesticide was affectedby the physico-chemical properties of each solidsystem, the freeze-dried form dissolving more rapidly. However, the physical association of-cyclodextrin and carbaryl enhanced the aqueoussolubility of the insecticide as well. 相似文献
10.
A simple and rapid assay is described for the determination of temafloxacin, 1-(2,4-difluorophenyl)-6-fluoro-7-(3-methylpiperazin-1-yl) 1,4- dihydro-4-oxoquinolin-3-carboxylic acid hydrochloride, in pharmaceutical formulations and in serum, based on the fluorescence emission of the drug. The assay of pharmaceuticals involves the measurement of fluorescence at 460 nm of the sample diluted in 0.1 H2SO4 with an excitation wavelenght of 276 nm and the assay of serum involves the use of the synchronous spectrofluorimetric method. An appropriate selection of the difference between the wavelengts of both monochromators (ΔΛ) allowed the direct and rapid determination of temafloxacin in serum samples without previous extraction. The procedure, which has been shown to be accurate, precise and sensitive requires only 0.25–0.4 ml of serum depending on the drug concentration. 相似文献