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关键词： Active film   Fish sarcoplasmic protein   Chitosan   Ginger essential oil   Nanoemulsion   Antioxidant activity  

摘要： The appeal for environment friendly films with bioactive components to replace synthetic plastic packaging has been increasing in recent years. In this study, ginger essential oil (GEO) nanoemulsion at different levels (0.5%, 1.0%, 1.5%, 2.0%, and 3.0%) were incorporated into fish sarcoplasmic protein (FSP) and chitosan (CH) blend films to evaluate the physical, mechanical, antioxidant, and thermal properties. The water distribution state of films was also determined by NMR transverse relaxation (T2) measurements. The tensile strength (TS) of samples was significantly reduced with increasing GEO nanoemulsion contents (p < 0.05), while the value of elongation at break (EAB) was the highest when the film with 1.0% GEO nanoemulsion. The addition of GEO nanoemulsion enhanced the water barrier properties and affected the water distributions of films, but had negative effects on thermal degradation of films. Scanning electric microscope (SEM) demonstrated the different microstructure at varied levels of GEO nanoemulsion and Fourier transform infrared (FTIR) spectroscopy gave the detailed information about the interactions at molecular level. These results revealed that FSP blended with CH was excellent film-forming material and mixing defined amount of GEO nanoemulsion into film-forming solution enhanced the physical and antioxidant properties of films.

关键词： Superheated steam   Soft wheat   Physicochemical properties   Cracker quality  

摘要： In order to study the effects of superheated steam (SS) treatment of wheat on the physicochemical properties of wheat flour and cracker quality, soft wheat was treated with SS and the pasting properties and solvent retention capacity (SRC) of wheat flour and cracker quality were determined. The results showed that both the physicochemical properties of wheat flour and cracker quality were significantly affected by SS treatment of wheat. Pasting properties of wheat flour were affected by SS treatment of wheat significantly, which indicated the increase of gelatinized starch and damaged starch. At the steam temperatures from 140 to 215 degrees C, 50% sucrose SRC (SuSRC), 5% sodium carbonate SRC (SCSRC), and water SRC (WSRC) increased with the extending of treatment time. Meanwhile, 5% lactic acid SRC (LASRC) and gluten performance index (GPI) initially increased and then decreased. Besides, the spread ratio, hardness and fracturability of crackers were improved. According to the results above, we concluded that SS treatment of wheat had significant effects on the physicochemical properties of wheat flour and could improve cracker quality in a relatively short time (shorter than 3 min). The most suitable condition for improving cracker quality was SS treatment of wheat at 165 degrees C for 3 min.

关键词： Size-exclusion chromatography   LC-MS/MS   Preclinical   Snakebite   Envenomation  

摘要： The quality of antivenom is governed by its safety and efficacy profiles. These quality characteristics are much influenced by the purity of antivenom content. Rigorous assessment and meticulous monitoring of antivenom purity at the preclinical setting is hence crucial. This study aimed to explore an integrative proteomic method to assess the physicochemical purity of four commercially available antivenoms in the region. The antivenoms were subjected to Superdex 200 HR 10/30 size-exclusion fast-protein liquid chromatography (SE-FPLC). The proteins in each fraction were trypsin-digested and analyzed by nano-ESI-liquid chromatography-tandem mass spectrometry (LC-MS/MS). SE-FPLC resolved the antivenom proteins into three major protein components of very high ( 200 kDa), high (100-120 kDa) and medium (<60 kDa) molecular weights. The major components (80-95% of total proteins) in the antivenoms were proteins of 100-120 kDa consisting of mainly the light and partially digested heavy immunoglobulin chains, consistent with F(ab')2 as the active principle of the anti venoms. However, LC-MS/MS also detected substantial quantity of large proteins (e.g. alpha-2-macroglobulins), immunoglobulin aggregates and impurities e.g. albumins in some products. The method is practical and able to unveil the quantitative and qualitative aspects of antivenom protein compositions. It is therefore a potentially useful preclinical assessment tool of antivenom purity.

关键词： Thermal spray coating   metals   particulates   particle size  

摘要： Thermal spray coating is a process that applies a molten metal product under pressure onto a surface. Although thermal spray processes have been used for decades, exposure to aerosols formed during thermal spray coating is an emerging risk. Reports indicate that high concentrations of aerosols composed of toxic metals (e.g. chromium) are generated in the workplace. A knowledge gap exists related to the physicochemical properties of thermal spray coating aerosols as well as any potential associated health effects. The objective of this manuscript was to review thermal spray coating and previous studies that have examined the aerosols produced from this process. A thermal spray coating generator and exposure system is also described that has recently been developed to further evaluate the physical and chemical properties of aerosols formed during thermal spray coating as well as to assess the possible health effects of this process in an effort to mitigate potential occupational health hazards related to the industry.

关键词： Polygalacturonase   Pectinmethylesterase   Dynamic viscosity   Turbidity   Carotenoids  

摘要： The effect of static and multi-pulsed high pressure processing (HPP) on the activity of hydrolyzing enzymes and the rheological properties of cloudy carrot juice during refrigerated storage (4 degrees C for 12 weeks) were investigated. The changes in the carotenoid profile, total polyphenolic content (TPC), antioxidant potential, and color were also studied. After HPP treatment, the activity of polygalacturonase (PG) and pectinmethylesterase (PME) decreased significantly. During the storage, the activity of PG increased by a maximum of 40% for 450 MPa, whereas PME activity decreased by a maximum of 76% for 300 MPa x 3 and 600 MPa. The apparent dynamic viscosity and turbidity changed after HPP treatment and storage. Seven carotenoids were identified in the untreated juice and their concentration increased significantly as increased pressure during the treatment. The carotenoids underwent significant degradation during the storage, which also correlated with changes in the a* and b* color parameters. The storage time also had a significant impact on the TPC and antioxidant capacity determined with DPPH and ABTS tests.

关键词： eudialyte   eudialyte concentrate   Fourier-transform infrared spectroscopy   scanning electron microscopy   surface morphology and physicochemical properties   microhardness   adsorption   flotation   high-power nanosecond electromagnetic pulses   dielectric barrier discharge  

摘要： The mechanism of change in the surface morphology, physicochemical properties, adsorbability and floatability of eudialyte concentrate as a result of exposure to high-power nanosecond pulses and dielectric barrier discharge in air under the atmospheric pressure is analyzed. The research methods were the Fourier-transform infrared spectroscopy, analytical electron microscopy, atomic force microscopy, confocal laser scanning microscopy, microhardness testing, flow potential determination and other techniques. The rational parameters of energy deposition and reagent regimes toward enhanced efficiency of complex eudialyte-bearing ore flotation are found.

关键词： Citrus   Satsuma mandarin   Quality   Variety   Regions   Principal component analysis  

摘要： Two Satsuma mandarin varieties (Miyagawa and Owari) from three typical cultivation regions in China (Zhejiang, Hubei, and Hunan province) were selected, and their physicochemical, nutritional, and enzymatic properties were comparatively studied. The results showed that Satsuma mandarin exhibited differences in quality parameters from both variety and region. From the principal component analysis (PCA), the samples were clearly distinguished. The L*, a*, b*, juice yield, titratable acidity (TA), total soluble solids (TSS), amino acid (AA), and carotenoid content of samples were more influenced by regions. The data obtained in this study will facilitate the characteristic evaluation of Satsuma mandarin and provide beneficial guidance for fruit processing.

关键词： Phthalocyanine   Silicon   Sonophotodynamic therapy   Prostate cancer cell line  

摘要： In this study, novel silicon phthalocyanines complexes have been synthesized, characterized and compared their antitumor efficiency of photodynamic, sonodynamic, sonophotodynamic on prostate cancer cells. Sonophotodynamic therapy (SPDT), a combination of photodynamic therapy (PDT) and sonodynamic therapy (SDT), is a new and promising method for the treatment of cancer cells. Although it is known that SPDT therapy has improved potential therapeutic result, the development of this method by working with different sensitizers has been lacking in the literature. To the best of our knowledge, this paper is the first study in the literature to calculate the photochemical properties of synthesized molecules and compare the results of photodynamic, sonodynamic and sonophotodynamic therapies on prostate cancer cells. In this study, new water soluble sensitizers with the different properties of linker hetematom (O or S) were synthesized, characterized and analyzed their photophysicochemical properties. Then, the effects of sonodynamic, photodynamic and sonophotodynamic on these sensitizers were examined in vitro on prostate cancer using PC3 cells. For this purpose, the cells were incubated with various concentrations of chemicals and subjected to ultrasound and/or light irradiation. According to MTT results, the sensitizers were showed quite efficiency for sonodynamic, photodynamic and sonophotodynamic therapies and decreased cell viability when compared with control group. Also apoptosis measurement data shows that the sensitizers (1a, 1b) would produce much better effects by combination sonodynamic and photodynamic therapies, especially the measurement of apoptotic cells in complex 2a reached 95% after SPDT therapy. As a result, it is seen that SPDT is a combination which has enhanced the therapeutic outcome.

关键词： Meats  

摘要： The objective of this research was to investigate the inclusion of pre-emulsified linseed oil as animal fat replacement on physicochemical properties and microstructure of sheep sausage. Control (0%) and formulations with 10, 20, 30, and 40% pre-emulsified linseed oil were elaborated. Chemical composition was affected by the partial replacement of animal fat by linseed oil, since the sausages prepared with 40% linseed oil showed the highest protein and ash content. In addition, these sausages presented the highest a* and b* values, WHC, and emulsion stability. As the levels of linseed oil increased, there was also an increase in shear force and lipid oxidation of cooked sausages. On the contrary, as the oil concentrations increased, the morphology has become more compact, indicating a good interaction of the oil emulsion with the other components. Thus, it is suggested the development of sheep meat sausages with 40% linseed oil to replace animal fat. Practical applications Consumers are becoming more and more aware of the link between diet and health. In this regard, reformulated meat products constitute an excellent opportunity for the meat industry, to improve the quality and image of meat and put in the market a product with health beneficial properties. Therefore, the use of pre-emulsified linseed oil as animal fat replacer is a viable strategy, which allows to increase the competitiveness of the sector and meet the demands of consumers. With this in mind, the present study clearly and coherently explains the application of this oil in a highly consumed product (sausage) as well as its benefits.

关键词： Surface treatment   Contact angle   Wettability   Surfactants  

摘要： Bacterial proliferation in the form of biofilm fixed on a substrate is the result of a set of physical, chemical and biological processes. Microbial adhesion to a substrate is often considered to be the result of physicochemical interactions between the substrate and the microbial cells. These interactions include electrostatic interactions, Van der Waals interactions and acid-base interactions (electron donor electron acceptor). The exact role of these physicochemical properties is still poorly documented. The purpose of this work is to provide some clarifications on this subject. The phenomenon of adhesion is often studied on clean surfaces, whereas in reality, it is always conditioned depending on its environment (medical, food or cosmetic). This is why in the present work we treated two different surfaces: glass and polyethylene, with diverse surfactants: nonionic, anionic and cationic. The choice of surfactants was motivated by its wide application in different fields. The physicochemical properties of the two substrata (treated and untreated) were defined using contact angle measurements. Moreover, the adhesive behavior of Staphylococcus aureus, as a bacterial model, on the studied substratum was assessed. The obtained results indicate that the physicochemical parameters of the two supports have changed in a specific way to each surfactant. The non-ionic surfactant turned both the surfaces more hydrophilic. However, the anionic and cationic surfactants have reversed the physicochemical characteristics of the surfaces. The correlation coefficients of the physicochemical properties and the adhesive behavior show that there is an association between the wettability of the two surfaces and the rate of the adherent cells.