The ingestion of contaminated water and food is known to cause food illness. Moreover, on assessing the patients suffering from foodborne disease has revealed the role of microbes in such diseases. Concerning which different methods have been developed for protecting food from microbes, the treatment of food with chemicals has been reported to exhibit an unwanted organoleptic effect while also affecting the nutritional value of food. Owing to these challenges, the demand for natural food preservatives has substantially increased. Therefore, the interest of researchers and food industries has shifted towards fruit polyphenols as potent inhibitors of foodborne bacteria. Recently, numerous fruit polyphenols have been acclaimed for their ability to avert toxin production and biofilm formation. Furthermore, various studies have recommended using fruit polyphenols solely or in combination with chemical disinfectants and food preservatives. Currently, different nanoparticles have been synthesized using fruit polyphenols to curb the growth of pathogenic microbes. Hence, this review intends to summarize the current knowledge about fruit polyphenols as antibacterial agents against foodborne pathogens. Additionally, the application of different fruit extracts in synthesizing functionalized nanoparticles has also been discussed. 相似文献
A comparative study of thermoresponsive poly(N-isopropylacrylamide)(PNIPAAm)-chitosan (CS)-based magnetic nanohydrogels (MNHGs) encapsulating functionalized Fe3O4 nanoparticles (NPs) in terms of the parameters governing their suitability for real hyperthermia is reported. Iron oxide
NPs functionalized with (a) citric acid (CA-Fe3O4), (b) ethylenediamine (Amine-Fe3O4) and (c) dimercaptosuccininc (DMSA-Fe3O4) have been synthesized and their encapsulation into MNHGs was obtained through physical encapsulation method. The structural
characterizations of synthesized materials include X-ray diffraction, FT-IR, TGA, ICP-AES and X-ray photoelectron spectroscopy
(XPS). Encapsulation of the functionalized NPs into MNHGs were observed in TEM micrographs, while SEM and AFM micrographs
confirmed their spherical morphology (~250–300 nm). Lower critical solution temperature (LCST) variation was measured by UV–visible
spectrophotometer and differential scanning calorimetry (DSC). MNHGs exhibited sufficient magnetization and heating ability
for hyperthermia. Typically, hydrogels containing CA-Fe3O4 (50 mg/ml) raised the temperature of the medium to 43 °C, a suitable dose for in vivo application in tumor-bearing mice. 相似文献
A fast and simple method for simultaneous detection and quantification of the medicinally important E- and Z-guggulsterone from raw oleogum-resin of Commiphora wightii by UPLC was developed. Both E- and Z-guggulsterone were extracted from naturally occurring resin samples using ethyl acetate and methanol. Chromatographic separation of the analytes and their respective standards were performed on an Acquity UPLC BEH C18 column followed by UV as well as a triple quadrupole detector in positive ionization mode. A linear gradient elution profile followed; mobile phase consisted of acetonitrile and 2 mM ammonium acetate in water. The method was validated over a range of 6.25 to 100 ng mL−1 for both the guggulsterones. The calibration curves were linear with correlation coefficients of 0.9998 for E-guggulsterone and 0.9999 for Z-guggulsterone. The LOD and LOQ were 1.65 and 5.02 ng mL−1 for E-guggulsterone and 2.57 and 7.79 ng mL−1 for Z-guggulsterone respectively. The average recovery of E-guggulsterone (104.63%) and Z-guggulsterone (104.33%) achieved from spiked samples were consistent and reproducible. The intra- and inter-day assay precision of the analytes over the entire concentration range was less than 2%. The developed method required only 6 min to complete a run including 1 min to equilibrate the system and hence suitable for high throughput applications. Efficiency, reliability and accuracy of the developed method were evaluated by analyzing resin sample from different C. wightii populations. The result of this study offers improvement in terms of speed and sensitivity as compared to previously reported methods.
The effect of initial microstructural deformation, alignment, and morphology on the response of wormlike micelle solutions
in transient uniaxial extensional flows is investigated using a pre-shear device attached to a filament stretching rheometer.
In filament stretching experiments, increasing the strength and the duration of the pre-shear just before stretch is found
to delay the onset of strain hardening. In these experiments, the wormlike micelle solution filaments fail through a rupture
near the axial midplane. The value of the elastic tensile stress at rupture is found to decrease with increasing pre-shear
rate and duration. The most dramatic effects are observed at shear rates for which shear banding has been independently observed.
The reduction in the strain hardening suggests that pre-shear before filament stretching might break down the wormlike micelles
reducing their size before stretch. Strain hardening is also observed in capillary breakup rheometry experiments; however,
the pre-sheared wormlike micelle solutions strain harden faster, achieve larger steady-state extensional viscosities and an
increase in the extensional relaxation time with increasing shear rate and duration. The difference between the response of
the wormlike micelles in filament stretching and capillary breakup experiments demonstrates the sensitivity of these self-assembling
micelle networks to pre-conditioning. 相似文献
An RP-LC method was developed and validated for comparing the pharmacokinetics profile of Vasa Swaras (leaf juice of Adhatoda vasica Nees., Fam. Acanthaceae) with that of the pure vasicine and vasicinone (chief marker compounds of A. vasica) upon oral administration of Vasa Swaras in rats, and also in different animal groups. Significant difference with p < 0.05 was found in the oral bioavailability of vasicine and vasicinone when administered as Vasa Swaras and as single vasicine and/or vasicinone. Vasicine and vasicinone were found to be more bioavailable from Vasa Swaras than pure vasicine and/or vasicinone. 相似文献
Porous silica matrices of different pore sizes with confined ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate) [BMIM] [PF6] were prepared by sol‐gel technique using a tetraethyl orthosilicate (TEOS) precursor with an aim to study the changes in physico‐chemical properties of ionic liquid on confinement. It is found that on confinement 1) melting point decreases, 2) fluorescence spectra shows a red shift and 3) the vibrational bands are affected particularly those of imadazolium ring, which interacts more with the walls of the silica matrix. Preliminary theoretical calculations suggest that SiO2 matrix interact more with the heterocyclic group of [BMIM] cation than the tail alkyl chain end group resulting in significant changes in the aromatic vibrations.相似文献
A sensitive and high throughput ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS-MS) method has been developed for the determination of pramipexole, a dopamine agonist, in human plasma. Sample preparation involved liquid-liquid extraction of pramipexole and ranitidine as the internal standard (IS) in ethyl acetate from 100 μL human plasma. The chromatographic separation is achieved on a Waters Acquity UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm) analytical column using an isocratic mobile phase, consisting of 10 mM ammonium formate (pH 7.50)-acetonitrile (15:85, v/v), at a flow-rate of 0.5 mL/min. The precursor → product ion transition for pramipexole (m/z 212.1 → 153.0) and IS (m/z 315.0 → 176.1) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) and positive ion mode. The method was validated over a wide dynamic concentration range of 20-4020 pg/mL. Matrix effect is assessed by post-column infusion experiment and the process efficiency were 91.9% and 85.7% for pramipexole and IS, respectively. The method is rugged and rapid with a total run time of 1.5 min and is applied to a bioequivalence study of 0.25 mg PPX tablet formulation in 30 healthy Indian male subjects under fasting condition. 相似文献