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11.
Veronika Valkov Hana úranov Nenad L. Vukovic Milena Vukic Maciej Kluz Miroslava Ka
niov 《Molecules (Basel, Switzerland)》2022,27(10)
The possibilities of the practical utilization of essential oils (EOs) from various plant species in the food industry have attracted the attention of the scientific community. Following our previous studies, the antifungal activities of three further commercial EOs, Melaleuca armillaris subsp. armillaris (rosalina; REO), Melaleuca quinquenervia (niaouli; NEO), and Abies alba (fir; FEO), were evaluated in the present research in respect to their chemical profiles, over four different concentrations, 62.5 μL/L, 125 μL/L, 250 μL/L, and 500 μL/L. The findings revealed that the major compounds of REO, NEO, and FEO were linalool (47.5%), 1,8-cineole (40.8%), and α-pinene (25.2%), respectively. In vitro antifungal determinations showed that the inhibition zones of a Penicillium spp. mycelial growth ranged from no inhibitory effectiveness (00.00 ± 00.00 mm) to 16.00 ± 1.00 mm, indicating a very strong antifungal activity which was detected against P. citrinum after the highest REO concentration exposure. Furthermore, the in situ antifungal efficacy of all EOs investigated was shown to be dose-dependent. In this sense, we have found that the highest concentration (500 µL/L) of REO, NEO, and FEO significantly reduced (p < 0.05) the growth of all Penicillium strains inoculated on the bread, carrot, and potato models. These results indicate that the investigated EOs may be promising innovative agents in order to extend the shelf life of different types of food products, such as bread, carrot and potato. 相似文献
12.
Shinji Ejiri Sinya Aoki Tetsuo Hatsuda Kazuyuki Kanaya Yoshiyuki Nakagawa Hiroshi Ohno Hana Saito Takashi Umeda 《Central European Journal of Physics》2012,10(6):1322-1325
We study the QCD phase structure at high temperature and density adopting a histogram method. Because the quark determinant is complex at finite density, the Monte-Carlo method cannot be applied directly. We use a reweighting method and try to solve the problems which arise in the reweighting method, i.e. the sign problem and the overlap problem. We discuss the chemical potential dependence of the probability distribution function in the heavy quark mass region and examine the applicability of the approach in the light quark region. 相似文献
13.
Elin Julianti Hana Oh Hyi-Seung Lee Dong-Chan Oh Ki-Bong Oh Jongheon Shin 《Tetrahedron letters》2012,53(23):2885-2886
Acremolin (1), a novel modified base, was isolated from the culture broth of the marine fungus Acremonium strictum. Based on combined spectroscopic analyses, the structure of this compound was that of a methyl guanine base containing an isoprene unit. In addition, the presence of a 1H-azirine moiety is unprecedented among natural products. This compound exhibited weak cytotoxicity against an A549 cell line. 相似文献
14.
There is evidence indicating that the cellular locus of PDT action by amphiphilic sensitizers are the cellular membranes. The photosensitization process causes oxidative damage to membrane components that can result in the cell's death. However, it was not yet established whether lipid oxidation can cause free passage of molecules through the membrane and, as a result, be the primary cause of the cell's death. In this work, we studied the effect of liposomes' lipid composition on the kinetics of the leakage of three fluorescent dyes, calcein, carboxyfluorescein and DTAF, which were trapped in the intraliposomal aqueous phase, after photosensitization with the photosensitizer deuteroporphyrin. We found that as the degree of fatty acid unsaturation increased, the photosensitized passage of these molecules through the lipid bilayer increased. We also found that the rate of leakage of these molecules was affected by their size and bulkiness as well as by their net electric charge. In liposomes that are composed of a lipid mixture similar to that of natural membranes, the observed passage of molecules through the membrane is slow. Thus, the photodynamic damage to lipids does not appear to be severe enough to be an immediate, primary cause of cell death in biological photosensitization. 相似文献
15.
Hana Macková Daniel Horák Eduard Petrovský Jana Kovářová 《Colloid and polymer science》2013,291(1):205-213
To prepare functionalized magnetic polymer particles that are thermally responsive, inverse emulsion copolymerization of N-isopropylacrylamide, N,N′-methylenebisacrylamide and glycidyl acrylate (GA) was investigated in paraffin oil in the presence of γ-Fe2O3 nanoparticles dispersed in a water/glycerol mixture. The resulting polymer particles were characterized regarding the morphology, size, polydispersity, iron content, and the temperature-dependent phase transition using optical microscopy, transmission electron microscopy, scanning electron microscopy, atomic absorption spectroscopy, and differential scanning calorimetry. Magnetic properties were examined using hysteresis loop measurements and by analyzing the magnetic susceptibility with respect to temperature. We have also investigated the influence of the concentration of γ-Fe2O3 and GA in monomers on properties of the particles (morphology, size, and presence of oxirane groups). The particles possessed a hollow structure as a result of phase separation between water/glycerol hydrophilic solvents in the polymerization feed and the forming polymer. Depending on the concentration of γ-Fe2O3 in the monomer phase, the magnetic hollow particles contained 5–24 wt% iron. In water, the particles gradually collapsed when the temperature was raised to 40 °C because the elevated temperature weakened hydration and the PNIPAAm chains gradually became more hydrophobic. 相似文献
16.
6-Allyloxypurines readily undergo palladium-catalysed Claisen rearrangement under mild conditions affording N 1-substituted hypoxanthines. In contrast with the previously reported protocol, the Claisen rearrangement can be performed using Pd(PPh3)4 or Pd(dba)2/dppf in dry THF at 60°C. The reaction can accommodate variously substituted allyl fragments to position N 1 of the hypoxanthine skeleton with high yields. Retention of the double bond configuration during rearrangement was observed. 相似文献
17.
18.
Hana M.A. Abumelha 《Journal of heterocyclic chemistry》2020,57(3):1011-1022
A series of novel nicotinonitrile derivatives were synthesized by hybridization with thiazole, pyrazole, and pyridine ring systems using 4-aminobenzohydrazide as link-bridge. The synthetic strategy of nicotinonitrile-thiazole analogues involves cyclization of the precursor N-phenyl thiosemicarbazide derivative 4 with chloroacetic acid and phenacyl bromide. The reaction of hydrazide 3 with acetylacetone and/or ethyl acetoacetate was applied as a synthetic route for accessing 2-((4-(pyrazole-1-carbonyl)phenyl)amino)-nicotinonitrile derivatives 9–10 . The 2-((4-(4-thiazolylidene-pyrazole-1-carbonyl)-phenyl)amino)nicotinonitriles 14–15 were obtained via a nucleophilic addition of pyrazolone 10 to phenyl isothiocyanate followed by cyclization with chloroacetone, phenacyl chloride, and/or ethyl bromoacetate. The 6-amino-4-aryl-3,5-dicyano-2-oxo-1-(4-substitutedbenzamido)-pyridines 19 were synthesized by Knoevenagel condensation N′-(2-cyanoacetyl)-benzohydrazide derivative 16 with substituted benzaldehydes followed by heating with malononitrile. All synthesized products were evaluated for their antioxidant potentialities using of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical cation delcolorization assay. The nicotinonitrile-thiazole hybrid 6b was found the most promising antioxidant agent with inhibition activity 86.27%. 相似文献
19.
Hualong Song Simon J. Allison Viktor Brabec Hannah E. Bridgewater Jana Kasparkova Hana Kostrhunova Vojtech Novohradsky Roger M. Phillips Jitka Pracharova Nicola J. Rogers Samantha L. Shepherd Peter Scott 《Angewandte Chemie (International ed. in English)》2020,59(34):14677-14685
Monosaccharides are added to the hydrophilic face of a self‐assembled asymmetric FeII metallohelix, using CuAAC chemistry. The sixteen resulting architectures are water‐stable and optically pure, and exhibit improved antiproliferative selectivity against colon cancer cells (HCT116 p53+/+) with respect to the non‐cancerous ARPE‐19 cell line. While the most selective compound is a glucose‐appended enantiomer, its cellular entry is not mainly glucose transporter‐mediated. Glucose conjugation nevertheless increases nuclear delivery ca 2.5‐fold, and a non‐destructive interaction with DNA is indicated. Addition of the glucose units affects the binding orientation of the metallohelix to naked DNA, but does not substantially alter the overall affinity. In a mouse model, the glucose conjugated compound was far better tolerated, and tumour growth delays for the parent compound (2.6 d) were improved to 4.3 d; performance as good as cisplatin but with the advantage of no weight loss in the subjects. 相似文献
20.
We show that any solution of the scalar conservation law (u+k*u)t+σ(u)x=0 starting from spatially periodic initial datum stabilizes to its integral mean as time goes to infinity. No convexity or ‘genuinely non-linear’ like conditions are assumed concerning σ. © 1997 by B. C. Teubner stuttgart–John Wiley & Sons Ltd. 相似文献