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关键词： Edible films   Physicochemical properties   Antioxidant and antibacterial activity  

摘要： Active edible films based on okara soluble dietary fiber (SDF), pectin, sodium carboxymethyl cellulose (CMC-Na) and thyme essential oil (TEO) were successfully prepared. We aimed to exploit biodegradable edible films and realize the full utilization ofwaste resources. The effects of different amounts of pectin on the properties and structural characterization of the composite film with or without TEO were studied using a solution casting evaporation method. In general, the addition of TEO can improve the properties of the composite membrane. Pectin was homogeneously distributedwithin the films and exhibited good interaction with the polymer matrix. The addition of pectin led to significantly higher mechanical and optical properties of the composite film, compared with SDF/CMC-Na composite film. The tensile strength reached 21.419 +/- 2.22MPa, and the minimum transparency reduced to 88.9%+/- 0.42%, with increasing pectin. Notably, the water resistance and oil resistance were enhanced. The composite films also possessed satisfactory antioxidant activity, with a DPPH-free radical scavenging rate of 46.33%+/- 0.72%, while antibacterial activity against E. coli and S. aureus bacteria was not obvious. Antioxidant and antibacterial SDF/pectin/CMC-Na composite films with enhanced mechanical, optical and barrier properties are excellent candidates for active edible packaging. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Excess molar volumes   Aniline   Butanols   Toluene   m-xylene  

摘要： A polemic is given regarding the volumetric data reported in the recent paper by Palaniappan and Nithiyantham. The authors' measured excess molar volumes are found to differ significantly from previously published literature values for four of the six systems studied. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Corn starch   Rice starch   Starch granule-associated proteins   Protease treatment   Physicochemical properties  

摘要： The objective of this study was to investigate the impact of removing starch granule-associated proteins (SGAPs), especially starch granule-associated surface and channel proteins, on the overall characteristics of corn and rice starches. Protease treatment predominantly removed SGAPs on surfaces and in channels of the starches without significant damage, as evidenced by confocal laser scanning microscopy coupled with protein-specific and non-reactive fluorescent dye staining. Compared to untreated starches, protease-treated (PT) starches showed higher solubility and lower swelling power. However, there were no changes in their gelatinization and melting temperatures, despite their higher relative crystallinity. The stability of swollen starch granules during shearing was reduced following SGAP removal, reducing their peak, final and setback viscosities of the paste. Taken together these results indicate that SGAP removal predominantly affects the rheological properties of starch. Furthermore, the lower setback in PT-starch pastes suggests short-term retrogradation may be retarded by protease treatment of starch.

关键词： ZnO/biochar   Photocatalysis   Sulfamethoxazole   Methyl orange   Composite  

摘要： Three different composites were produced, based on zinc oxide and biochar (ZnO/biochar), varying the type of biomass (Salvinia molesta: SM;exhausted husk of black wattle: EH;and sugarcane bagasse: SB), with pyrolysis under mild conditions at 350 and 450 degrees C. Evaluation was made of the capacities of the composites for photocatalytic degradation of sulfamethoxazole antibiotic (SMX) andmethyl orange dye (MO). The properties of the prepared compositeswere influenced by the biomass source, with larger crystallite size (SB), lower band gap energy (SM), higher specific surface area (SB), and larger pore size (SM) resulting in higher photocatalytic efficiency. Good degradation results were obtained using these innovative photocatalysts prepared at low temperatures, when compared to ZnO/biocharmaterials reported in previous studies. The best degradation capacities were obtained for the composites produced at 450 degrees C from SB and SM, with 99.3 and 97% degradation of SMX after 45 min, and 90.8 and 88.3% degradation of MO after 120 min, respectively. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Sodium caseinate   Pectin   Composite film   Rheology   Mechanical properties   Physical stability  

摘要： Present work focused on the role of high methoxyl pectin (HMP) in rheology and physical stability of sodium caseinate (CAS) film-forming solution as well as mechanical and structural characteristics of its edible film. CAS-HMP films were fabricated at different blend ratio. Incorporation of HMP into CAS solution decreased pH value of the solution, acting as a natural acidifier. Turbidity and particle size distribution measurements indicated that some level of protein-polysaccharide interactions developed in 50CAS:50HMP and 25CAS:75HMP. Analysis of steady-state shear viscosity of film solutions showed a transition from Newtonian to shear-thinning flow behaviour by addition of HMP. Dynamic viscoelasticity evaluations revealed that the elasticity of solutions decreased by increasing HMP ratio. Physical stability of solutions was assessed over time using a Turbiscanner. All solutions showed distinct mechanisms of destabilization. 50CAS:50HMP and 25CAS:75HMP samples appeared to be the most stable solutions. Increasing CAS:HMP ratio from 100:0 to 25:75 increased the water solubility and elongation at break of edible films from 27.16 to 63.70% and 2.36 to 16.53%, respectively. SEM analysis exhibited a homogenous microstructure in 50CAS:50HMP and 25CAS:75HMP. DSC thermograms displayed lower glass transition temperatures in HMP-incorporated films. Presence of the interactions among biopolymers in biocomposites was confirmed by FTIR spectra. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Fish skin   Collagen peptides   Maillard reaction products   Antioxidant activity   Emulsifying property   Foaming property  

摘要： To improve the utilization of cod skin collagen peptides (CSCP), we heated them with xylose at 80 degrees C, 100 degrees C, and 120 degrees C for up to 150 min to prepare xylose-CSCP Maillard reaction products (MRPs), and then investigated their physicochemical and functional properties. The results showed that Arg, Lys, Phe, and Asp were the major amino acids involved in the Maillard reaction. After being heated at 120 degrees C for 150 min, the ABTS scavenging activity and reducing power of xylose-CSCP MRPs were 99.59% and 0.887 absorbance units, respectively. Xylose-CSCP MRPs had better emulsifying properties and foaming properties than CSCP. Furthermore, 26 volatile compounds, including 2,5-dimethyl-pyrazine and 2-ethyl-3,5-dimethylpyrazine, were identified from xylose-CSCP MRPs by gas chromatography-ion mobility spectrometry. Newly formed heterocyclic compounds might be responsible for the flavor and antioxidant capacity of xylose-CSCP MRPs. These results suggest the potential for xylose-CSCP MRPs to serve as functional food ingredients.

关键词： 2-N-propanoyl anthranilic acid   Charge transfer complex   Spectroscopic study   X ray diffraction analysis   Theoretical calculations  

摘要： The 2-aminobenzimidazole (ABZ)-2-N-propanoyl benzoic acid 1 which is an intermediate of synthesis of various heterocyclic compounds was synthesized. The structure of 1 was confirmed by FT-IR, NMR (1D and 2D) spectra and XRD. The molecular structure of compound 1 was characterized by single-crystal X-ray structure determination and theoretical calculations based on DFT, HF and MP2 methods. The NBO analysis was used mainly in order to study the influence of electronic delocalization on the mechanism. Experimental, DFT, HF and MP2/6-31G(d) optimized bond lengths, bond angles and hydrogen bonding for the structure are studied also. The structure analysis shows that the 3D-supramolecular architecture of 1 is stabilized by means six-(S6) intramolecular and eight-(R-2(2)(8)) membered intermolecular hydrogen bonds, together with extensive C-H center dot center dot center dot O and C-H center dot center dot center dot pi interactions between the carboxylate anion and the 2-aminobenzimidazolium cation. Furthermore, parameters derived from density functional theory in a local sense, in particular the softness and Fukui function were used to interpret and predict the mechanism of the reaction. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Metal complexes   4-nitroimidazole   Hydrazones   Spectral characterization  

摘要： Complexes [sb(L1 Cl-2] (1), [ Sb(L-2)Cl-2] (2), [Ag(HL)NO3] (3-5, HL = HL1-H2L3), [Cu(HL1)Cl-2] (6), [Cu(L2)Cl] (7) and [Cu(HL3)(2)]center dot 2HCl (8) with 2-acetylpyridine-4-nitroimidazolehydrazone, H2Ac4NO(2)Im (HL1), 2-benzoylpyridine-4-nitroimidazolehydrazone, H2Bz4NO(2)Im (HL2) and 2-formyl-8-hydroxyquinoline-4nitroimidazolehydrazone, H2Q4NO(2)Im (H(2)L3) were obtained and characterized by means of numerous spectroscopic techniques. EPR studies of complexes (6-8) were performed and the crystal structures of (1) and [Cu(HL3)(2)]center dot 2DMF (8a) were determined. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Forward osmosis   Degradation   Brine   Membrane fouling   XDLVO  

摘要： This study investigated the chemical stability of various forward osmosis (FO) after static exposure to multi effect distillation (MED) brine. The water flux, forward salt flux (FSF), and specific reverse salt flux (SRSF) were evaluated to evaluate the membrane performance degradation. The changes in the physicochemical properties of FO membranes were elucidated via characterization techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), goniometer, and zeta potential analyzer. Moreover, the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) approach was used to predict the changes in the membrane fouling propensity. The results showed that the cellulose triacetate (CTA) membrane suffered deacetylation and chain cleavage due to hydrolysis, whereas the thin-film composite (TFC) membrane experienced degrafting due to oxidation. The selectivity reductions of both membranes were observed according to the increase in FSF and SRSF. Furthermore, the decreasing attractive XDLVO interaction energies of the degraded CTA membrane indicated the improvement of anti-fouling properties. In contrast, the anti-fouling properties of the TFC membrane were severely reduced since the attractive XDLVO interaction energies increased.

关键词： Pleurotus ostreatus   Selenium-enriched polysaccharide   Antitumor activity   Organic selenium  

摘要： Selenium-enriched polysaccharides have been gaining great attention for their antitumor activity in recent years. In this study, a novel seleniumpolysaccharide fraction (Se-POP-3) produced by Pleurotus ostreatuswas characterized and its antitumor activity explored at cellular level. Results showed that Se-POP-3 has 25.9 mu g/g of selenium, an average molecular weight of 16,106 Da, and is mainly composed of mannose, glucose and galactose with a molar ratio of 1.7:49.6:2.4. Spectra analysis revealed Se-POP- 3 as a pyranopolysaccharide linked by alpha-glycoside bonds in the main chain, and selenium may occur in the form of C-O-Se and Se=O. A single sphere of Se-POP-3 has 50-60 nm in aqueous solution, even though it can agglomerate to form larger spherical structures. In vitro experiments with cancer and normal cell lines showed that Se-POP-3 can induce apoptosis and inhibit migration of cancer cells. Potential anticancer mechanism is that Se-POP-3 can disrupt the Bax/Bcl-2 protein ratio and inhibit the epithelial-to-mesenchymal transition (EMT) in cancer cells. Se-POP-3 showed no significant effect on the growth of normal cell lines. Se-POP-3 showed great potential as a broad-spectrum antitumor agent and dietary supplement. (c) 2020 Published by Elsevier B.V.