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关键词： ZnONS   5-FU   DFT   Band gap   Total energy   Fermi level  

摘要： Zinc oxide nanosheet (ZnONS) is a favorable route to utilize for carrier various drug molecules in the human body. To realize suitable and optimized adsorption of the four anticancer drug molecules (6-MP, GB, 5-FU and CP) on the ZnONS surface, we substituted various concentrations of Zn atoms with Ga impurities on the ZnONS surface. Then, we studied different electronic properties of the nGa-doped ZnONS and numerous drug molecules adsorbed with nGa-doped ZnONS in the vertical and horizontal directions via a DFT calculation. There are exacted interesting results. The behavior of ZnONS is converted from semiconducting to semimetal. That means the huge quantity of charges are carried in the system. Besides, n Ga-doped ZnONS become more stable and lower reactive due to the total energy is increased. The exchange-correlation and electrostatic energies are improved, excepted kinetic energy has opposite behavior. Due to we observed the structure becomes more stable with different concentrations of Ga impurities;we studied the above electronic properties of the drug molecules adsorbed with n Ga-doped ZnONS in the vertical and horizontal directions. We found out the electronic properties is not only depended on the type of the drug molecules, but also depended on the direction of the drug molecule. So, the electronic properties are very sensitive to the drug molecules in the horizontal more than in the vertical direction due to the shape of the electronic band structure is exchanged and the overlapping of the conduction and valence bands are more increased in the horizontal than in the vertical directions. Then, we can employ n Ga-doped ZnONS as a carrier of drug molecules.

关键词： Physicochemical properties  

摘要： In this study, steam explosion (SE) was used to process Qingke (highland hull-less barley). Under the optimum conditions of steam pressure (P) of 2.34 MPa, processing time (T) of 37.0 s and initial water content (W) of 10.0%, the optimum values of expansion ratio (ER), unpopped kernel ratio (UKR), total polyphenol content (TPC), total flavone content (TFC), and antioxidant index (ABTS) were 3.24, 0.192, 3.81 mg GA/g DW, 3.24 mg rutin/g DW and 14.0 mg ASC/g DW, respectively. Optimization of physicochemical properties showed that SE resulted in excellent expansion properties of Qingke while preserving its active components and antioxidants. By comparing the analysis results of scanning electron microscopy (SEM), hydration, vitamin E, beta-glucan, pentosan, and dietary fiber of the SE treated Qingke with the raw and traditional roasting treated Qingke, SE has been demonstrated to be a better processing technology for Qingke and could well maintain the nutrients of Qingke. Practical applications Qingke is a special type of barley without hull that mainly grows in highlands. The processing conditions for Qingke with steam explosion have been successfully optimized and the shape and nutritional value of Qingke can be well preserved. The comparison between traditional roasted and steam explosion treated Qingke showed that steam explosion technology can better puff up and retain the nutrients of Qingke. This work provides an efficient processing method for comprehensive utilization of Qingke.

关键词： Multienzyme modification   Maize starch   Branch density   Transglycosylation   V-type complex  

摘要： A proposed strategy to increase the number of alpha-1,6 glycosidic bonds and the branch density of maize starch to some extent to promote the formation of a V-type complex by using an enzymatic method was studied. The molecular weight values were decreased after the starch underwent maltogenic amylase (MA)/glucan branching enzyme (GBE)/pullulanase (PU) treatment. The MA and MA -> GBE modifications decrease the average chain length and increase the branch density of the starch. X-ray diffraction showed that the diffraction intensity of the inclusion complex became stronger after the starch was modified by dual- and triple-enzymes. The MA (30 min)-PU-starch-lauric acid (LA) complex had the highest melting enthalpy values among all of the analysed samples. FTIR indicated that there was more ordered crystalline structure formed in MA (30 min) and MA -> GBE modified samples. The swelling power values of enzyme-treated starch-LA complex occurred in the following order: MA (60 min)/PU > MA/GBE/PU > PU > MA (30 min)/PU. In vitro digestibility results indicated that the enzyme resistance of the starch-LA complex was enhanced by applying the MA -> PU and MA -> GBE -> PU modification to the starch.

关键词： Oil body   Xanthan gum   Stability   Microstructure   Particle size  

摘要： Stable oil body holds great implications in food industry. Due to the instability of safflower oil body, we optimized various parameters of oil body such as pH, ionic strength and stabilizer. Safflower oil bodies were relatively stable at pH 8 and 10 mM monatomic saline ions. In order to further stabilize oil body, xanthan gum was screened from 10 stabilizers and the concentration was determined to 0.3 g/100 g. Further testing efficiency of xanthan gum in holding oil bodies stability under various thermal and ultrasonic treatments demonstrated that xanthan gum-coated oil bodies were thermally stable even at 90 degrees C. Moreover, they retained size and did not aggregate. However, the ultrasonic intensity above 200 w over 30 mM ruptured oil bodies leading to their coalescence. We demonstrated that xanthan gum stabilized safflower oil bodies which could expand their exploitation.

关键词： Glycosylation   maltodextrin   physicochemical properties   soya bean protein isolate   structure  

摘要： The effect of mixture and conjugation with maltodextrin (MD) in aqueous solution on the structural and physicochemical properties of soya bean protein isolate (SPI) was investigated. Although the mixing of MD would not change the distribution of secondary structure and tertiary conformation of SPI, the protein aggregation was promoted through hydrophobic interaction, which resulted in the decrease in solubility and the improvement of gel strength and water holding capacity (WHC) of SPI/MD mixture. However, glycosylation decreased alpha-helix and increased beta-structure. The bathochromic shift of the fluorescence emission maximum wavelength for SPI/MD conjugates was promoted, resulting in less compact tertiary conformation. These structural modifications might be the reason for the changes in the physicochemical properties of conjugates. After glycosylation, the surface hydrophobicity and solubility were increased, the average particle size was decreased, and the gelation properties were weakened including gel strength and WHC.

关键词： Thymol   beta-Cyclodextrin   Hierarchical porous structure   Drug release   Antibacterial activity  

摘要： As an effective natural antibacterial component, the low water solubility of thymol (THY) has stemmed its potential in biomedical application. Here, beta-cyclodextrin (beta-CD) and THY were self-assembled to form water-soluble inclusion complex (IC). The successful formation of IC was confirmed via H-1 NMR. As an antibacterial agent, the resultant IC was then incorporated into cellulose acetate (CA) fibrous matrix with hierarchical structure (nanopores on porous fibrous webs) via electrospinning (CA/THY/beta-CD), and the pure THY was also encapsulated into CA for comparison (CA/THY). In vitro dissolution tests demonstrated that CA/THY/beta-CD fibrous membrane exhibited sustained drug release, which abided by non-Fickian diffusion. Besides, the CA/THY/beta-CD fibrous membrane exhibited more effective and long-lasting antibacterial activity against S. aureus. Furthermore, the combination of hierarchical porous structure with sustained drug release endowed the CA/THY/beta-CD fibrous membrane with good cytocompatibility. Taken together, the CA/THY/beta-CD fibrous membrane could be an attractive candidate for wound dressing material.

关键词： Durability study   Salt soluble protein   Water holding capacity   Texture profile analysis (TPA)   Greenland   Shelf-life  

摘要： The annual global catch of Atlantic cod (Gadus morhua L.) is above 1,000,000 tons, and a large proportion is preserved and sold as frozen products. In Greenland, a new innovative fishing method centred on capture-based aquaculture has been developed. To compare the new fishing and processing method with the conventional method, the texture, colour, water holding capacity, salt soluble proteins and sensory properties of fillets were evaluated during 12 months of frozen storage. High quality life (HQL) and practical storage life (PSL) were determined for each fishing and processing method based on sensory evaluation, and by using water holding capacity and the salt soluble protein fraction as indices of quality. Capture-based aquaculture fishing and related processing increased frozen storage durability regarding texture attributes, blood content and sensory properties compared to the conventional method. Lowering the storage temperature to -40 degrees C increase the HQL to > 12 months compared to a HQL of 4-6 months at -20 degrees C.

关键词： Nitroglycerin   Metformin   Mebendazole   Hamsters   BHK-21/C13   Fibrosarcoma  

摘要： We investigated the effect of nitroglycerin with metformin on fibrosarcoma in hamsters. Syrian golden hamsters of both sexes, weighing approximately 60 g, were randomly allocated to control and experimental groups, with 8 animals per group. In all groups, 2x10(6) BHK-21/C13 cells in 1 ml were injected subcutaneously into the animals' backs. Peroral treatment carried out with nitroglycerin 25 mg/kg daily, or with metformin 500 mg/kg daily, or with a combination of nitroglycerin 25 mg/kg and metformin 500 mg/kg daily. Later validation experiments were conducted with double doses of the single therapy and additional rescue doses of mebendazole 460 mg/kg daily, via a gastric probe after tumor inoculation. After 2 weeks, when the tumors were approximately 2-3 cm in the control group, all animals were sacrificed. Blood samples were collected for hematological and biochemical analyses, the tumors were excised and weighed, and their diameters and volumes were measured. The tumor samples were pathohistologically and immunohistochemically assessed for proliferation marker protein Ki-67, proliferating cell nuclear antigen PCNA, hematopoietic progenitor cell antigen CD34, cluster of differentiation 31 (CD31), cytochrome c oxidase subunit 4 (COX4), mitochondria marker Cytochrome C, glucose transporter 1 (GLUT1) and inducible nitric oxide synthase (iNOS), and the main organs were toxicologically tested. The Ki-67 and PCNA positivity and the cytoplasmic marker (CD34, CD31, COX4, Cytochrome C, GLUT1, iNOS) immunoexpression in the tumor samples were quantified. The combination of nitroglycerin and metformin significantly inhibited fibrosarcoma growth in hamsters without toxicity, compared to monotherapy or control. The results were validated and confirmed in the subsequently accomplished experiment with doubled doses of the single drug therapy and in the rescue experiment with addition of mebendazole. The single treatments did not show significant antisarcoma effect, regardless of t

关键词： Silver nanoparticles  

摘要： The effect of carboxymethyl cellulose and guar gum-based silver nanoparticles coatings was investigated on the postharvest storage stability of the loquat (Eriobotrya japonicaLindl.) during 1 month storage at two different temperatures (4 and 8 degrees C). The results revealed that coated fruit (Fomesa and silver nanoparticles coating) have lower weight loss, total soluble solids (TSSs), total sugars, reducing sugars, and nonreducing sugars as compared with control samples at both temperatures. Moreover, the coated samples have a higher concentration of ascorbic acid, total phenolic contents (TPCs), antioxidants, and titratable acidity. Additionally, silver nanoparticle-based coating reduced the weight loss, TSSs, total sugars, reducing sugars, and nonreducing sugars;and increased ascorbic acid, TPCs, antioxidants, and titratable acidity as compared with Fomesa coating during 1 month storage. Moreover, loquat fruit stored at 4 degrees C have higher quality during storage as compared with loquat samples stored at 8 degrees C. Overall results indicated that silver nanoparticle-based coating can be used commercially to increase physicochemical and nutraceutical properties of loquat during storage. Practical applications Silver nanoparticles are increasingly used for the preservation of food commodities due to their wider application, cost effectiveness, and higher reactivity. Previously, no study was carried out to investigate the effect of silver nanoparticle-based coating on the physicochemical properties of loquat. The results of this study suggest that silver nanoparticles-based coatings have potential to increase the shelf life and postharvest quality of loquat fruit. The findings of this research will be helpful to reduce the postharvest losses of loquat fruit.

关键词： Ordered mesoporous carbon   Pd nanoparticles   Oxygenated carbon functionalities   Furfural hydrogenation  

摘要： Two series of nanostructured carbon replicas were synthesized through a hard-templating method using ordered SBA-15 or disordered mesoporous spherical silica gel as the templates and furfuryl alcohol or sucrose as the carbon source. They were explored to synthesize the Pd catalysts (ca. 1.5 wt% Pd loading) by the colloid-based microemulsion procedure which allowed preparing the catalysts of monodispersed Pd particles of similar size (4-5 nm). The palladium phase in the catalysts (e.g. the Pd particles distribution and extent of agglomeration) varied depending on the textural and surface characteristics of the carbon replicas. In the furfural hydrogenation studied as a probe reaction (2-propanol, 35 degrees C, 6 bar H-2), furfuryl alcohol and tetrahydrofurfuryl alcohol were the major products formed. The catalytic reactivity has been related to the properties of the Pd phase including the surface Pd concentration and the extent of the Pd particles aggregation accompanied by the nearest palladium environment expressed by the surface O/Pd atomic ratio. At high O/Pd ratio the reaction slowed down because of a facilitated furfuryl alcohol adsorption resulting most probably in a blockage of the active sites. The SiO(2 )sucrose system provided the catalyst which was characterized by relatively low O/Pd ratio with well-dispersed Pd particles and the highest and stable activity for the furfural hydrogenation. The SBA-series catalysts, with lower O/Pd and more aggregated Pd particles, exhibited lower activity but somewhat higher tendency to the tetrahydrofurfuryl alcohol formation.