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51.
52.
Abstract

Spices and aromatic herbs can be contaminated with mycotoxins, since of their preharvest, postharvest, and storage conditions. In this study, 112 samples of different spices and aromatic herbs were evaluated for their mycotoxins content by HPLC-MS/MS in order to highlight their possible risk linked with human use. The results showed that mycotoxins were occasionally detected only in samples of coriander, laurel, mint, rosemary, and verbena. In both geographical origins a different contamination was detected. Among the investigated mycotoxins, AFB2, AFG1, AFG2, T2 and HT2 were detected, whereas none of the samples contained AFB1 and FB1. The co-occurrence of two toxins were observed for some samples of rosemary and verbena. This study indicates that it is essential minimize the toxins in agriculture, industry, and food-product manufacturing for the consumer health protection.  相似文献   
53.
In the present study, the phytochemical composition and bioactivities of A. maroccanus (AM) and A. radiatus (AR), two ecotypes collected in the Demnate road and Essaouira regions, respectively, were studied to highlight a pharmacological interest and to enable possible pharmaceutical development. To this end, methanolic and ethyl acetate extracts were prepared for each ecotype by fractionation; next, their phytochemical composition was evaluated by spectrophotometric and chromatographic analysis. Moreover, in line with the available evidence for Anacyclus spp. and their traditional use, a screening of bioactivities, including antioxidant, hypoglycemic, antiglycative, chelating, and antibacterial activities, was performed. The extracts were characterized by high amounts of polyphenols, tannins, and flavonoids, especially in the methanolic extracts; these samples were also enriched in carotenoids despite a lower chlorophyll content. Chlorogenic acid and rutin were the major identified compounds. The extracts also showed interesting hypoglycemic, antiglycative, and antibacterial properties, although with differences in efficacy and potency. Present results provide more scientific basis to the ethnopharmacological uses of Anacyclus spp. and suggest a further interest in AM and AR ecotypes as natural sources of bioactive compounds and/or phytocomplexes for possible pharmaceutical and nutraceutical developments.  相似文献   
54.
The synthesis from 3-thiochromanone of indole and quinoline derivatives is reported. The structures of the compounds obtained, which are analogs of carcinogenic nitrogen polycycles, were determined by means of mass spectrometry and high resolution NMR spectrometry. In the latter case, Nuclear Overhauser Enhancements (NOE) allow the unequivocal determination of structures. Furthermore, direct (or“through space”) 1H-1H couplings are reported and related to the NOE.  相似文献   
55.
Three novel bis-urea fluorescent low-molecular-weight gelators (LMWGs) based on the tetraethyl diphenylmethane spacer—namely, L1, L2, and L3, bearing indole, dansyl, and quinoline units as fluorogenic fragments, respectively, are able to form gel in different solvents. L2 and L3 gel in apolar solvents such as chlorobenzene and nitrobenzene. Gelator L1 is able to gel in the polar solvent mixture DMSO/H2O (H2O 15% v/v). This allowed the study of gel formation in the presence of anions as a third component. An interesting anion-dependent gel formation was observed with fluoride and benzoate inhibiting the gelation process and H2PO4, thus causing a delay of 24 h in the gel formation. The interaction of L1 with the anions in solution was clarified by 1H-NMR titrations and the differences in the cooperativity of the two types of NH H-bond donor groups (one indole NH and two urea NHs) on L1 when binding BzO or H2PO4 were taken into account to explain the inhibition of the gelation in the presence of BzO. DFT calculations corroborate this hypothesis and, more importantly, demonstrate considering a trimeric model of the L1 gel that BzO favours its disruption into monomers inhibiting the gel formation.  相似文献   
56.
Despite considerable advances in recent years, challenges in delivery and storage of biological drugs persist and may delay or prohibit their clinical application. Though nanoparticle-based approaches for small molecule drug encapsulation are mature, encapsulation of proteins remains problematic due to destabilization of the protein. Reverse micelles composed of decylmonoacyl glycerol (10MAG) and lauryldimethylamino-N-oxide (LDAO) in low-viscosity alkanes have been shown to preserve the structure and stability of a wide range of biological macromolecules. Here, we present a first step on developing this system as a future platform for storage and delivery of biological drugs by replacing the non-biocompatible alkane solvent with solvents currently used in small molecule delivery systems. Using a novel screening approach, we performed a comprehensive evaluation of the 10MAG/LDAO system using two preparation methods across seven biocompatible solvents with analysis of toxicity and encapsulation efficiency for each solvent. By using an inexpensive hydrophilic small molecule to test a wide range of conditions, we identify optimal solvent properties for further development. We validate the predictions from this screen with preliminary protein encapsulation tests. The insight provided lays the foundation for further development of this system toward long-term room-temperature storage of biologics or toward water-in-oil-in-water biologic delivery systems.  相似文献   
57.
We introduce suitable exponential operators and use the multi-dimensional polynomials considered by Hermite and subsequently studied by P. Appell and J. Kampé de Fériet, H. W. Gould and A. T. Hopper, and G. Dattoli et al. in order to obtain explicit solutions of classical boundary-value problems with periodic data. Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 51, Differential Equations and Their Applications, 2008.  相似文献   
58.
Two species of edible clams Venerupis aurea laeta and Cerastoderma edule glaucum from Ganzirri Lake (Sicily, Italy) were investigated to determine OCP and PCB residues by GC-MS. Thirty-five samples were examined for two years in order to perform: a) their actual contamination; b) the daily dietary exposure of seafood consumers to the pollutants in question. In all the clams analysed in this study, PCB and OCP (4,4′-DDE) residues are always below the limits fixed by law. It seems that there is some seasonality of concentrations observed. In fact the more high concentrations of residues are detected in the hot months, for both species and years. Given the consumption of clams and the values obtained in this study for the two species analysed, it is possible estimate that the average daily dietary intake of NDL-PCB and of 4,4′-DDE for adults is really low.  相似文献   
59.
A 80???J, 6?fs, CEP-stable high-contrast injector is demonstrated. The device relies on standard pulse post-compression in hollow-core fiber followed by a temporal filter based on cross-polarized wave generation. Pulses with a Gaussian spectrum over 350?nm, centered at 750?nm, are generated. Temporal measurements show that the contrast of the few-cycle pulses is enhanced on a femtosecond and picosecond time scale. The carrier-envelope phase stability is preserved (0.3?rad RMS). These performances make the system an ideal seed laser for high-power, high-contrast OPCPA systems.  相似文献   
60.
Planar organic electrochemical transistors (OECTs) using PEDOT:PSS as the channel material and nanostructured carbon (nsC) as the gate electrode material and poly(sodium 4‐styrenesulfonate (PSSNa) gel as the electrolyte were fabricated on flexible polyethylene terephthalate (Mylar®) substrates. The nsC was deposited at room‐temperature by supersonic cluster beam deposition (SCBD). Interestingly, the OECT acts as a hybrid supercapacitor (to give a device that we indicate as transcap). The energy storage ability of transcaps has been studied with two cell configurations: one featuring PEDOT:PSS as the positive electrode and nsC as the negative electrode and another configuration with reversed electrode polarity. Potentiostatic charge/discharge studies show that both supercapacitors show good performance in terms of voltage retention, in particular, when PEDOT:PSS is used as the positive electrode. Galvanostatic charge–discharge characteristics show typical symmetric triangular shape, indicating a nearly ideal capacitive behavior with a high columbic efficiency (close to 100%). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 96–103  相似文献   
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