Interaction of hydrocolloids (xanthan gum, locust bean gum, guar gum, and high-methoxyl pectin) with macrocomponents of dough (water, starch, and protein) was evaluated by different techniques. (1)H spin-spin NMR relaxation assays were applied to study the mobility of the gluten-hydrocolloid-water matrix, and the amount of freezable water was determined by differential scanning calorimetry (DSC). Starch gelatinization parameters (T, enthalpy) were also analyzed by DSC. The influence of additives on the protein matrix was studied by Fourier transform (FT) Raman assays; analysis of the extracted gliadins and glutenins was performed by electrophoresis (SDS-PAGE). A significantly higher molecular mobility was found in matrices containing xanthan gum, whereas pectin led to the lowest molecular mobility. Freezable water showed a trend of increasing in the presence of hydrocolloids, particularly under conditions of water restriction. Starch gelatinization final temperature was decreased when hydrocolloids were added in the presence of enough water. In general, FT-Raman and SDS-PAGE indicated that hydrocolloid addition promoted a more disordered and labile network, particularly in the case of pectin addition. On the other hand, results obtained for dough with guar gum would indicate a good compatibility between this hydrocolloid and the gluten network.
Vanadium compounds are known for a variety of pharmacological properties. Many of them display antitumoral and osteogenic effects in several cell lines. Free radicals induce the development of tumoral processes. Natural polyphenols such as flavonoids have antioxidant properties since they scavenge different free radicals. For these reasons it is interesting to investigate the effects of a new complex generated between the vanadyl(IV) cation and the flavonoid hesperidin. The complex has been synthesized and characterized by physicochemical methods. Spectroscopic analysis revealed a 1:1 stoichiometry of ligand:VO and coordination by deprotonated cis-hydroxyl groups to the disaccharide moiety of the ligand. The complex improves the superoxide dismutase (SOD)-like activity of the ligand, but the scavenging of other radicals tested does not change upon complexation. When tested on two tumoral cell lines in culture (one of them derived from a rat osteosarcoma UMR106 and the other from human colon adenocarcinoma Caco-2), the complex enhanced the antiproliferative effects of the free ligand, and this effect correlated with the morphological alterations toward apoptosis. Also, on the osteoblastic cell line the complex stimulated cell proliferation and collagen type I production at low concentrations. At higher doses the complex behaved as a cytotoxic compound for the osteoblasts.
We have carried out a structural and vibrational theoretical study for the citric acid dimer. The Density Functional Theory (DFT) method with the B3LYP/6-31G* and B3LYP/6-311++G * * methods have been used to study its structure and vibrational properties. Then, in order to get a good assignment of the IR and Raman spectra in solid phase of dimer, the best fit possible between the calculated and recorded frequencies was carry out and the force fields were scaled using the Scaled Quantum Mechanic Force Field (SQMFF) methodology. An assignment of the observed spectral features is proposed. A band of medium intensity at 1242 cmtogether with a group of weak bands, previously not assigned to the monomer, was in this case assigned to the dimer. Furthermore, the analysis of the Natural Bond Orbitals (NBOs) and the topological properties of electronic charge density by employing Bader's Atoms in Molecules theory (AIM) for the dimer were carried out to study the charge transference interactions of the compound.
The development of new vanadium derivatives with organic ligands, which improve the beneficial actions (insulin-mimetic, antitumoral) and decrease the toxic effects, is of great interest. A good candidate for the generation of a new vanadium compound is the flavonoid quercetin because of its own anticarcinogenic effect. The complex [VO(Quer)(2)EtOH]( n ) (QuerVO) has been synthesized and characterized by means of different spectroscopic techniques (UV-vis, Fourier transform IR, electron paramagnetic resonance) and its magnetic and stability properties. The inhibitory effect on bovine alkaline phosphatase (ALP) activity has been tested for the free ligand, the complex as well as for the vanadyl(IV) (comparative purposes). The biological activity of the complex on the proliferation of two osteoblast-like cells in culture, a normal one (MC3T3E1) and a tumoral one (UMR106), has been compared with that of the vanadyl(IV) cation and quercetin. The differentiation osteoblast markers ALP specific activity and collagen synthesis have been also tested. In addition, the effect of QuerVO on the activation of the extracellular regulated kinase (ERK) pathway is reported. The bone antitumoral effect of quercetin alone was established with the cell proliferation assays (it inhibits the proliferation of the tumoral cells and does not exert any effect on the normal osteoblasts). Moreover, the complex exerts osteogenic effects since it stimulates the type I collagen production and is a weak inhibitory agent upon ALP activity. Finally, QuerVO stimulated the ERK phosphorylation in a dose-response manner and this activation seems to be involved as one of the possible mechanisms for the biological effects of the complex.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.