Curcumin (diferuloyl methane) is the physiologically and pharmacologically active component of turmeric (Curcuma longa L.). Solubility and stability of curcumin are the limiting factors for realizing its therapeutic potential. β-Lactoglobulin (βLG), the major whey protein, can solubilize and bind many small hydrophobic molecules. The stability of curcumin bound to βLG in solution is enhanced 6.7 times, in comparison to curcumin alone (in aqueous solution). The complex formation of curcumin with βLG has been investigated employing spectroscopic techniques. βLG interacts with curcumin at pH 7.0 with an association constant of 1.04 ± 0.1 × 10(5) M(-1) to form a 1:1 complex at 25 °C. Entropy and free energy changes for the interaction derived from the van't Hoff plot are 18.7 cal mol(-1) K(-1) and -6.8 kcal mol(-1) at 25 °C, respectively; the interaction is hydrophobic in nature. The interaction of βLG with curcumin does not affect either the conformation or the state of association of βLG. Competitive ligand binding measurements, binding studies with denatured βLG, effect of pH on the curcumin-βLG interaction, Förster energy transfer measurements, and molecular docking studies suggest that curcumin binds to the central calyx of βLG. These binding studies have prompted the preparation and encapsulation of curcumin in βLG nanoparticles. Nanoparticles of βLG prepared by desolvation are found to encapsulate curcumin with >96% efficiency. The solubility of curcumin in βLG nanoparticle is significantly enhanced to ∼625 μM in comparison with its aqueous solubility (30 nM). Nanoparticles of βLG, by virtue of their ability to enhance solubility and stability of curcumin, may fit the choice as a carrier molecule.

The metabolic sensor Per-Arnt-Sim (Pas) domain-containing serine/threonine kinase (PASK) is expressed predominantly in the cytoplasm of different cell types, although a small percentage is also expressed in the nucleus. Herein, we show that the nuclear PASK associates with the mammalian H3K4 MLL2 methyltransferase complex and enhances H3K4 di- and tri-methylation. We also show that PASK is a histone kinase that phosphorylates H3 at T3, T6, S10 and T11. Taken together, these results suggest that PASK regulates two different H3 tail modifications involving H3K4 methylation and H3 phosphorylation. Using muscle satellite cell differentiation and functional analysis after loss or gain of Pask expression using the CRISPR/Cas9 system, we provide evidence that some of the regulatory functions of PASK during development and differentiation may occur through the regulation of these histone modifications.

This study was undertaken to quantitate a single virus suspension in culture medium without any pre-processing. The electrical capacitance per virus particle was used to identify the kind of virus present by measuring the suspension (virus plus medium) capacitance, de-embedding the medium contribution, and dividing by the virus count. The proposed technique is based on finding the single virus effective dielectric constant which is directly related to the virus composition. This value was used to identify the virus type accordingly. Two types of viruses thus tested were further quantified by a biochemical technique to validate the results. Furthermore, non-organic nanoparticles with known concentration and capacitance per particle were identified using the proposed method. The selectivity of the method was demonstrated by performing electrical measurements on a third virus, revealing that the proposed technique is specific and sensitive enough to permit detection of a few hundred virus particles per milliliter within a few minutes.

Biocompatible carbon quantum dots (CQDs) have recently attracted increased interest in biomedical imaging owing to their advantageous photoluminescence properties. Numerous precursors of fluorescent CQDs and various fabrication procedures are also reported in the literature. However; the use of concentrated mineral acids and other corrosive chemicals during the fabrication process curtails their biocompatibility and severely limits the utilization of the products in cell bio-imaging. In this study; a facile; fast; and cost-effective synthetic route is employed to fabricate CQDs from a natural organic resource; namely bread; where the use of any toxic chemicals is eliminated. Thus; the novel chemical-free technique facilitated the production of luminescent CQDs that were endowed with low cytotoxicity and; therefore; suitable candidates for bioimaging sensors. The above mentioned amorphous CQDs also exhibited fluorescence over 360–420 nm excitation wavelengths; and with a broad emission range of 360–600 nm. We have also shown that the CQDs were well internalized by muscle myoblasts (C2C12) and differentiated myotubes; the cell lines which have not been reported before.