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Significant experimental effort has been explored to search and characterize high-k materials with magnetodielectric effect (MDE) of series of rare earth (RE) oxide (RE2O3) nanoparticles (NPs) embedded in SiO2 glass matrix by a sol-gel route. Properly annealed sol-gel glass (in which RE = Sm, Gd, and Er) shows colossal response of dielectric constant along with diffuse phase transition and MDE around room temperature. The radial distribution functions, reconstructed from extended x-ray absorption fine structure, show the shortening of RE3 + -O depending on the RE2O3 NP size, which is consistent with oxygen vacancy induced dielectric anomaly. The magnetoresistive MDE is very much conditioned by magnetic property of RE2O3 NP grain, the degree of deformation of the lattice and constituent host. [ABSTRACT FROM AUTHOR]

Lycium barbarum L., a traditional Chinese herb widely used in Asian countries, has been demonstrated to be protective against chronic diseases such as age-related macular degeneration. The objectives of this study were to determine the carotenoid content in L. barbarum by high-performance liquid chromatography-mass spectrometry, followed by preparation of a carotenoid nanoemulsion to evaluate the mechanism of inhibition on HT-29 colon cancer cells. The highest extraction yield of carotenoids was attained by employing a solvent system of hexane-ethanol-acetone (1:1:1, v/v/v). Nine carotenoids, including neoxanthin (4.47 μg g -1 ), all-trans-zeaxanthin and its cis-isomers (1666.3 μg g -1 ), all-trans-β-cryptoxanthin (51.69 μg g -1 ), all-trans-β-carotene and its cis-isomers (20.11 μg g -1 ), were separated within 45 min and quantified using a YMC C 30 column and a gradient mobile phase of methanol-water (9:1, v/v) (A) and methylene chloride (B). A highly stable carotenoid nanoemulsion composed of Capryol TM 90, Transcutol ® HP, Tween 80 and deionized water was prepared with a mean particle size of 15.1 nm. Characterization of zeaxanthin standard, blank nanoemulsion, carotenoid extract and carotenoid nanoemulsion by differential scanning calorimetry curves and Fourier transform infrared spectra revealed a good dispersion of zeaxanthin-dominated carotenoid extract with no significant chemical change after incorporation into nanoemulsion. The in vitro release kinetic study showed a higher release profile at pH 5.2 than at physiological pH 7.4, suggesting a rapid release of carotenoids in the acidic environment (pH 4.5-6.5) characteristic of tumors. Both the carotenoid nanoemulsion and the extract were effective at inhibiting growth of HT-29 colon cancer cells, with an IC 50 of 4.5 and 4.9 μg ml -1 , respectively. Also, both treatments could up-regulate p53 and p21 expression and down-regulate CDK2, CDK1, cyclin A and cyclin B expression and arrest the cell cycle at G 2 /M. The study may form a basis for further exploration of L. barbarum nanoemulsion in cancer treatment.

An HPLC-DAD-MS method with high accuracy and precision was developed for determination of prenylflavonoids and hop bitter acids in beer lee, a by-product from beer brewing process. Four prenylflavonoids and nine hop bitter acids can be simultaneously separated in 29 min using a Thermo HyPURITY C18 column in combination with diode array dectector and mass spectrometer with HPLC solvent gradient system of phosphoric acid aqueous solution at pH 1.6 and acetonitrile at a flow rate of 1.5 mL/min and detection wavelength at 314 nm. Beer lee is found to contain isoxanthohumol (36.2 μg/g), xanthohumol (29.6 μg/g), 8-prenylnaringenin (7.84 μg/g), 6-prenylnaringenin (19.2 μg/g), cohumulone (44.7 μg/g), humulone (123 μg/g), adhumulone (21.8 μg/g), colupulone (44.2 μg/g), lupulone (33.2 μg/g), and adlupulone (5.76 μg/g)., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The objectives of this study were to determine the distribution of functional components in peel and pulp of Luffa cylindrica and evaluate their anti-inflammatory activity on RAW 264.7 murine macrophage cells. Phenolics and flavonoids were present in abundant amounts in aqueous extract of peel, but in ethyl acetate extracts of peel, oleanolic acid, carotenoids and chlorophylls dominated. Both ethanol and ethyl acetate extracts in peel and pulp decreased production of nitric oxide in LPS-induced RAW 264.7 cells, whereas the ethanol extract mitigated secretion of prostaglandin E(2). Furthermore, all the extracts significantly inhibited IL-6 production, but remained ineffective in retarding generation of IL-1β and TNF-α. Ethyl acetate extract of peel reduced expression of inducible nitric oxide synthase, but enhanced expression of cyclooxygenase 2. Both ethyl acetate extracts of peel and pulp mitigated expression of p-IκBα, while the latter attenuated expression of p-ERK, and all the extracts failed to inhibit JNK phosphorylation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)