Highly Efficient Deamidation of Wheat Gluten by Glucose-Citric Acid-Based Natural Deep Eutectic Solvent: A Potential Effective Reaction Media

An efficient technique using citric acid and glucose based natural deep eutectic solvent (G-C-NADES) was developed to obtain ultrahigh deamidated wheat gluten (UDWG) (deamidation degree (DD) > 90%). FTIR and ¹H NMR indicated intensive hydrogen bonds (HBs) in G-C-NADES supermolecules. Quantum chemical calculations and molecular dynamic simulations demonstrated that 10 wt % diluted G-C-NADES still had a myriad of HBs. Physicochemical results showed UDWG had DD up to 92.45% after G-C-NADES deamidation, that is, 22% higher than citric-acid-DWG with a weak degree of hydrolysis (1.75%). Conformational characterization demonstrated the obvious conversion from α-helix to β-sheet via FTIR, the least amount of disulfide bonds by Raman spectra, and more exposure of tryptophan residues by fluorescence measurement for UDWG. It is proven that enhanced accessible conformation of WG reached with HBs of G-C-NADESs could contribute to the improvement on nucleophilic attack of deamidation, declaring that G-C-NADES might be a potential solvent for obtaining an ultrahigh deamidation for WG to successfully guarantee the safety of wheat gluten based cereal food regarding to lowering its allergy.

Growth, electrical and optical studies, and terahertz wave generation of organic NLO crystals: DSTMS

The raw material of 4-N,N-dimethylamino-4′-N′-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS) is synthesized by a condensation method under the catalysis of piperidine.

Spectroscopic, Quantum Chemical, Physical and Antioxidant Studies on 2-Amino 4-Picolinium 4-Nitrobenzoate – An Organic Crystal for Nonlinear Optical and Biological Applications

The title compound, 2-amino 4-picolinium 4-nitrobenzoate (2A4PNB), has been identified as a nonlinear optical material and its good quality single crystals were grown from methanol solution. It crystallizes in monoclinic system with the non-centro symmetric space group Pc. Its structure and chemical compositions were confirmed by the X-ray diffraction and microanalysis studies, respectively. FTIR, UV-Visible-NIR, NMR and photoluminescence (PL) spectra have been recorded and extensive spectroscopic investigations have been carried out. The grown crystals have been subjected to micro hardness and photoconductivity studies to explore its physico chemical properties. The free radical scavenging activity of the complex has been determined against DPPH and H2O2 radicals. In addition, the quantum chemical studies were performed on the isolated 2A4PNB molecule using DFT calculations at the B3LYP/6-311++G (d,p) basis set.

Investigation on the growth, structural, HOMO–LUMO and optical studies of 1-ethyl-2-[2-(4-hydroxy-phenyl)-vinyl]-pyridinium iodide (HSPI) – a new stilbazolium derivative for third-order NLO applications

The organic third-order non-linear optical crystal HSPI, a new derivative of the stilbazolium family, was successfully synthesized and the optical quality single crystal was grown by a slow evaporation technique for the first time.