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关键词： High pressure processing   Soy protein-pectin-coumarin complex   Multi-spectroscopic approaches   Physicochemical stability   DPPH radical scavenging ability  

摘要： This study was devoted to explore the synergistic effect of pressure level and pectin addition on the binding and structural properties of soy protein-coumarin (S-C) complexes through multi-spectroscopic approaches to elucidate the protective effect of the complexes on physicochemical stability of coumarin. High pressure processing (HPP) could reinforce the intermolecular hydrogen bonding and hydrophobic interaction between soy protein and coumarin (at a mass ratio of 3:1), resulting in the formation of complexes with smaller particle sizes and more compact structure, the effects were more pronounced as the pressure > 200 MPa. The incorporation of pectin provided a better protection of coumarin against UV and thermal degradation and improved remarkably the physical stability of complex particles during 30 days at 4 ?C. In comparison with free coumarin, the coumarin retention of S-P-C (400) was up to 55.3 ? 1.7 % when exposure to UV for 120 min, 61.7 ? 2.9 % under 90 ?C heating, and 96 ? 1.5 % after storage. However, the DPPH radical scavenging ability of S-C complexes decreased with HPP treatment and the addition of pectin. The present work revealed that soy protein-pectincoumarin ternary complexes developed by HPP could be an effective delivery system for bioactive compounds with applications in functional food ingredient.

关键词： xanthan   producer strain   Xanthomonas   bentonite  

摘要： A new, highly efficient xanthan-producing strain, Xanthomonas campestris M 28, was obtained. It produces up to 28 g/L of the polysaccharide on a molasses medium, which is almost two times higher than the productivity of the NRRL B 1459 strain. Whole-genome sequencing of the strain was performed with the Illumina method and nanopore sequencing. The genome of X. campestris M 28 contained one chromosome of 5102828 nucleotides with an average G + C content of 65.03%. The structure and physicochemical and rheological properties of the obtained xanthan were studied. It was found that the addition of xanthan to the bentonite dispersion led to the formation of primary clay particles (70 nm) and aggregates of similar to 190 nm without the formation of a precipitate. This indicated the interaction of macromolecules with particles and aggregates with the formation of polymer-clay bridging structures. This ensures the stability of clay dispersions and makes it possible to achieve the required rheological properties of drilling fluids based on xanthan obtained in a molasses medium, thereby reducing its cost.

关键词： diamond   silicon carbide   reaction sintering   physicochemical interactions in the carbon (diamond)-silicon system   sintering of diamond particles   Turing reaction-diffusion mechanism   microstructure   triple periodic surfaces of minimal energy  

摘要： The chemical processes occurring during the interaction of carbon (diamond) with silicon are experimentally investigated. Thermal analysis of the interaction of diamond with silicon is carried out. This made it possible to determine the mechanism of the synthesis of silicon carbide and subsequent reaction sintering of diamond particles based on Turing's reaction-diffusion process and the formation of a microstructure consisting of triple periodic surfaces of the minimal energy.

关键词： Digestive enzymes' inhibitory effects   in vitrodigestion and fermentation   mulberry leaf polysaccharides   physicochemical properties   short-chain fatty acids  

摘要： The investigation aimed at determining the impact of sequential simulated digestion on the physicochemical properties and digestive enzymes inhibitory effects of the polysaccharides fraction (MLP-2) ofMorus albaL. leaves as well as itsin vitrofermentation behaviours. After artificial salivary, gastric and intestinal digestions, the chemical components and microstructure of MLP-2 were altered with significantly (P < 0.05) decreased molecular weight. The alpha-amylase and alpha-glucosidase inhibitory activities of MLP-2 were significantly (P < 0.05) improved throughout simulated digestion. MLP-2I, the intestinal digested fraction of MLP-2, could significantly (P < 0.05) decrease the pH value of fermented culture and increase the short-chain fatty acids (SCFA) concentrations, especially acetic, propionic and butyric acids. In conclusion, MLP-2 could be gradually degraded under simulated digestion with altered physicochemical properties and enhanced alpha-amylase and alpha-glucosidase inhibitory effects, and further utilised by human gut microbiota to decrease pH value and promote SCFA production.

关键词： Spent mushroom substrate   Hydrothermal carbonization   Hydrochar   Isoconversional   Combustion kinetic   Thermodynamic analysis  

摘要： Hydrothermal carbonization (HTC) was employed for the conversion of the spent mushroom substrate (SMS) into a carbonaceous hydrochar. The effect of operating temperature (180, 200, 220, 240, and 260 ?C) on the physicochemical, structural, and combustion properties of the obtained hydrochars was analyzed. The HTC treatment caused the increase of the higher heating value (HHV) and the lower heating value (LHV) of hydrochars for 58 % and 65 % in comparison with SMS, respectively. Analysis of morphology and functional groups showed the formation of microspheres and cracks on the hydrochar surface, which are predominantly dominated by aromatic and oxygen-rich functional groups. Thermal and kinetics analysis showed that HTC treatment improves the combustion behavior of the obtained solids. Combustion kinetic parameters of SMS and hydrochars were determined by the methods of Kissenger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO). The thermodynamic parameters and pre-exponential factors reveal a complex mechanism of SMS and hydrochars decomposition process.

关键词： Yeast  

摘要： This study evaluated the effect of indigenous Lactococcus lactis on the physicochemical, microbiological, and sensory parameters of thermo-coagulated acid whey protein (TAWP) during 8 days of refrigerated storage. Even a low amount of L. lactis biomass (0.2% w/w) expressed its protective properties in TAWP: reduced the counts of yeast and mold up to 0.5 log cfu/g, slowed down proteolysis (as five times less water-soluble nitrogen was detected in samples with added lactococci), and enhanced the sensory properties (consistency, odor pleasantness, and overall acceptability) by > 10%. These results suggested that TAWP could be used as a nutritious co-product with potential functional properties and a suitable matrix for selected beneficial lactic acid bacteria. Novelty Impact Statement This study evaluated the effect of indigenous Lactococcus lactis on the physicochemical, microbiological, and sensory parameters of thermo-coagulated acid whey protein (TAWP) during 8 days of refrigerated storage. Even a low amount of L. lactis biomass (0.2% w/w) expressed its protective properties in TAWP: reduced the counts of yeast and mold up to 0.5 log cfu/g, slowed down proteolysis (as five times less water-soluble nitrogen was detected in samples with added lactococci), and enhanced the sensory properties (consistency, odor pleasantness, and overall acceptability) by > 10%. These results suggested that TAWP could be used as a nutritious co-product with potential functional properties and a suitable matrix for selected beneficial lactic acid bacteria.

关键词： Bigel   Organogel   12-hydroxystearic   Candelilla wax   Rheology   Stability  

摘要： Bigels have been studied as topical formulations for its benefits over sensory and drug delivery parameters. However, there is still few evidences about the properties of the combination of organogelators, oily phases and bioactive molecules into rheological and stability behavior. We investigated the use of classical organogelators (candelilla wax and 12-hydroxystearic acid) and oily phases (sunflower and mineral oil) in 5/95 organogel/ polymeric hydrogel ratio to compare vitamin E bigels with its corresponding emulsions. The rheological measurements, microstructure, physical and oxidative stability properties and biological behavior were evaluated. The obtained oil-in-water bigels and emulsions showed crystallization pattern at the interface with high thermal and centrifuge-stress stability. Viscoelastic weak gels were obtained with higher thixotropy and consistency of 12-hydroxystearic bigels. The diameter of the inner phase was increased by vitamin E, despite its little influence over physical and oxidative stability of bigels and emulsions. Those findings indicated that sensory attributes may be regulated by the organogel composition.

关键词： film-forming solution   thin film   composite material   sol-gel synthesis   calcium phosphate material  

摘要： To produce materials based on the P2O5-CaO-TiO2 system, we have prepared film-forming solutions of four compositions, containing 70, 75, 85, and 95 wt % titanium(IV) oxide. The suitability of the film-forming solutions for film growth has been shown to be limited to viscosity values in the range from 3.4 to 3.7 mm(2)/s. At 70 and 75 wt % titanium(IV) oxide, a CaTiO3 (perovskite) phase has been identified in the P2O5-CaO-TiO2 system. The most uniform deposition of particles, with a large number of open pores after immersion in simulated body fluid (SBF), has been observed at 70 and 75 wt % titanium(IV) oxide. These compositions are thus the best suited for practical application.

关键词： O/W lavender essential oil nano-emulsion   Gelatin   Antibacterial   Antioxidant   Cherry tomatoes  

摘要： This study presented a facile approach for fabricating oil-in-water lavender essential oil nano-emulsions (LEONs) with excellent antibacterial and antioxidant activities. Besides, LEONs with different LEO content (50, 100, 200 and 300 mu L/10 mL) were incorporated to the matrix of gelatin (GL) for preparing multifunctional GL-LEONs films, which exhibited strong antibacterial properties against Staphylococcus aureus, Escherichia coli and Listeria monocytogenes, as well as excellent antioxidant activities. Additionally, the GL-LEONs films exhibited sustained release characteristics, excellent UV light barrier performances and good heat-sealing properties. Furthermore, the GL-LEONs films were applied to the preservation of cherry tomatoes at 25 +/- 2 degrees C for 7 days. The results revealed that the deterioration of cherry tomatoes packaged with the GL-LEONs films was suppressed during storage, which mainly reflected in reducing weight loss, delaying the degradation of titratable acids and phenolic components, and inhibiting the growth of microorganisms.

关键词： Fine slag   Acid treatment   Physicochemical properties   Gasification reactivity  

摘要： Fine slag (FS), which is a by-product from coal gasification, is composed of inorganic miner-als and residual carbon. Acid treatment has high efficiency to separate the residual carbon in FS but the changes of properties of FS treated by acid remain unclear. To have a deep under-standing of effects of acid treatment on physicochemical properties and gasification activity of FS, FS was subjected to different acid treatment, and then were characterized using Nitrogen adsorption technique, Raman spectroscopy and thermo-gravimetric analyzer. The results showed that the combined treatment with hydrochloric acid and hydrofluoric acid can remove the almost all mineral matters. Acid treatments did not modify the continuous and complete pores structure of FS. While, hydrochloric acid has a major influence on carbon structure, which produces the highest carbon actives and amorphous carbon. Nitric acid has positive influence on carbon structure transformation to crystalline structure. Notably, the gasification time can be shortened by the reduction of ash content. The carbon active sites in samples governed the initial reactivity while at the late stage of gasification the amount of inorganic elements controlled the gasification rate. (c) 2021 Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.