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关键词： quasi-ternary systems   single crystals   physicochemical analysis   solid solutions   chemical transport reactions  

摘要： For the first time, the GeSb2Te4-PbSb(2)Te(4)section of the GeTe-Sb2Te3-PbTe quasi-ternary system is investigated by complex methods of physicochemical analysis (differential thermal, microstructural, and X-ray phase analysis with microhardness measurement and density determination) and the phase diagram is constructed. It is established that the section is a partially quasi-binary section of the GeTe-Sb2Te3-PbTe quasi-ternary system. The GeSb2Te4-based region of the solid solution (15 mol % PbSb2Te4) is revealed. The congruently melting compound GePbSb(4)Te(8)is formed with the ratio of the initial components 1:1. Single crystals of the GePbSb(4)Te(8)quaternary compound are formed by the method of chemical transport reactions. The unit-cell parameters of the GePbSb(4)Te(8)compound, which crystallizes in the orthorhombic crystal system, are determined:a= 5.06 angstrom,b= 9.94 angstrom, anc= 11.62 angstrom. It is established by investigation of the temperature dependences of certain electrical parameters of the GePbSb(4)Te(8)compound and (GeSb2Te4)(x)(PbSb2Te4)(1 -)(x)solid solution that the alloys havep-type conductivity.

关键词： piperine   HP β   CD   food-grade natural compound   antioxidant   molecular docking  

摘要： The purpose of the present study was to improve the aqueous solubility, dissolution, and antioxidant activity of the water-insoluble drug piperine (PIP). The study was performed by preparing PIP binary inclusion complex (PIP BIC) and piperine ternary inclusion complex (PIP TIC) by different methods. The effect of a hydrophilic auxiliary substance (TPGS) was assessed with addition to PIP and hydroxypropyl beta cyclodextrin (HP beta CD) complex. The phase solubility study was performed to evaluate the complexation efficiency and stability constant. The aqueous solubility, dissolution, physicochemical assessment, antioxidant activity, antimicrobial activity, and molecular docking were further evaluated to check the effect of the complexation of PIP. The stability constant (Ks) value was found to be 238 and 461 M-1 for the binary and ternary inclusion complex. The dissolution study results showed a marked enhancement of release in comparison to pure drug. XRD and SEM studies revealed the presence of more agglomerated and amorphous structures of PIP, which confirmed the formation of complexes. The results of DPPH radical scavenging and antimicrobial activity showed a significant (p < 0.05) enhancement in scavenging activity for PIP TIC (microwave irradiation (MI)). The docking studies have revealed that the binding affinity of TPGS at the PIP-HP beta CD complex was -5.2 kcal/mol.

关键词： almond   microstructure   symbiotic   whey protein   yogurt alternative  

摘要： A plain symbiotic almond yogurt-like product was formulated and developed using a plant-based starter YF-L02 (Streptococcus thermophilus,Lactobacillus *** withLactobacillus acidophilus,Lactobacillus paracasei, andBifidobacterium animalis) and inulin;0.6% polymerized whey protein (PWP), 0.3% pectin, and 0.05% xanthan gum were optimized for the formula of the almond yogurt alternative. Two groups with/without calcium citrate and vitamin D(2)were prepared and analyzed for chemical composition, changes in pH, viscosity, and probiotic survivability during storage at 4 degrees C for 10 weeks. The results showed that (1) over 10 weeks storage, the differences in the pH, viscosity, and probiotic survivability between the control and the fortified samples were not significant (P> 0.05);(2) the pH of both yogurt samples decreased 0.2 units while their viscosity slightly increased during storage;(3) the populations ofL. paracaseiandB. animalisremained above 10(6)cfu/g during the storage, whereas the population ofL. acidophilusdecreased dramatically during the first 4 weeks, especially the control group;(4) the microstructure was examined by scanning electron microscopy, revealing a compact and denser gel structure formed by 0.6% PWP with the presence of 0.3% pectin and 0.05% xanthan gum. In conclusion, PWP might be a proper gelation agent for the formulation of symbiotic almond yogurt alternative. Practical Application In this study, polymerized whey protein was used as a gelation agent to formulate symbiotic almond yogurt alternatives with comparable physical texture and probiotic survivability to dairy yogurt during storage. This technology may be used for the development of plant-based fermented foods.

关键词： Red swamp crayfish   Bacterial communities   Physicochemical properties   Ultrasound cleaning   Ozone water cleaning  

摘要： The objective of this research was to investigate the impact of ultrasound cleaning (U) combined with ozone water cleaning (O-3) on the bacterial communities and physicochemical properties of red swamp crayfish. After single-factor experiments, 600 W and 45 min for U and 13.28 mg/L and 20 min for O(3)were selected as optimal parameters. The combination of ultrasound followed by ozone water cleaning (U/O-3) showed the better total viable count (TVC) reduction effect in crayfish than ozone water cleaning followed by ultrasound cleaning (O-3/U) and simultaneous ozone water and ultrasound cleaning (U+O-3). As expected, U/O(3)significantly reduced the relative abundance ofPseudoalteromonadaceae,Fusobacteriaceae, andPlesiomonas_shigelloides, and increased the cleanness of crayfish. Compared with the control (samples cleaned with water), the samples subjected to U/O(3)treatment led to the myofibril separations of tail meat and an increase (P< 0.05) in the pH, myofibril fragments index (MFI), and thiobarbituric acid-reactive substance (TBARS) content. However, no significant influence (P> 0.05) was found on the physical and sensory qualities, including the expressible moisture, cooking loss, springiness, overall appearance, odor, taste, and integrity of tail meat. Therefore, U/O(3)could be a potential cleaning method for crayfish in the food industry.

关键词： Egg white gel   Metal ions   Gelation   Characteristics   Digestibility  

摘要： Preserved egg is an alkaline egg product and traditionally relied on the addition of certain heavy metal ions to ensure its quality. To solve the possible safety problem of the heavy metal ions (Cu2+) in preserved egg and improve the pickling process, the effects of alternative ions (K+, Ca2+, Zn2+ and Fe3+) at various levels (0%-0.133%) on the gelation behavior and digestion characteristics of egg white (EW) proteins under strong alkali treatment were investigated. Results showed that multivalent ions promoted the particle size of alkali-induced EW aggregates. As the concentration of K+ increased, the soluble protein content, water-holding capacity, hardness and springiness of alkali-induced egg white gels (EWGs) were superior to those of Ca2+, Zn2+ and Fe3+. EWGs had larger turbidity and rougher microstructures when Ca2+ or Fe3+ was added. The primary intermolecular forces involved in the formation of EWG were ionic bonds and disulfide bonds. Fourier transform infrared spectroscopy (FTIR) analysis showed that strong alkali and metal ions induced the secondary-level structure to interconvert. Adding metal ions increased the gel digestibility. Electrophoresis results showed no significant difference among various bands of the soluble part of EWGs. Principal component analysis showed that four principal components were extracted, explaining 88% of total variance. It was concluded that low concentration of multivalent ions improved the performance of gels. K+ had a significant enhancement on gel properties, while Ca2+, Zn2+ and Fe3+ were more conducive to the formation of polymers, thereby affecting the properties of alkali-induced EWGs by forming or destroying intermolecular forces.

关键词： authentication   crude phytochemical contents   Diospyros montana   histology   scanning electron microscopy  

摘要： Adulteration is the root cause of producing not only a chemically and pharmacologically inferior but also in some instances hazardous or poisonous drug. Despite availability of several techniques, microscopy and physicochemical analyses are the most practical approaches for crude drug authentication. Hence, the present study aimed to evaluate morphological, microscopic, and physicochemical properties of root, bark, leaf, and fruit ofDiospyros montanaMorphological properties were determined by sensory organs, whereas microscopic features of cross-sections and powders were determined by light and scanning electron microscopy. The proximate and fluorescence analyses were performed using the standard guidelines. The physical examination of fresh, shade-dried, and powdered material showed no significant change in color. The identifying cellular structures included cuboidal cork, pitted tracheids, scalariform, reticulate and spiral xylary vessels, and rosettes, raphide, and cuboidal calcium oxalate crystals. The stomatal number, stomatal index, vein-islet and vein-termination number, and palisade ratio in the leaf were found to be 293.91 +/- 32.68 mm(-2), 64.18 +/- 3.42%, 22.00 +/- 3.81 mm(-2)and 38.40 +/- 5.81 mm(-2), and 3.85 +/- 0.60, respectively. Total ash, acid insoluble ash, water soluble ash and sulfated ash of leaf (9.00 +/- 0.50%, 1.67 +/- 0.23%, 2.00 +/- 0.22% and 14.50 +/- 0.99%, respectively), foaming index of bark and root (111.11 +/- 2.11), and swelling index of fruit (19.00 +/- 3.45) were higher than the other parts. The powder of different parts showed characteristic colors in the daylight and UV light upon treatment with various regents. The plant was found to be rich in saponins, fibers, and flavonoids. The results of the present study may serve as identifiers of different parts ofDiospyros montana.

关键词： +Strand RNA virus   Protein expression   Consensus proteins   Antibody binding   Protein modeling and design   Circular dichroism   Mass spectroscopy  

摘要： There is a pressing need for new vaccines against alphaviruses, which can cause fatal encephalitis (Venezuelan equine encephalitis virus (VEEV) and others) and severe arthralgia (e.g. Chikungunya virus, CHIKV). These positive-strand RNA viruses are diverse and evolve rapidly, meaning that the sequence of any vaccine should cover multiple strains that may be quite different from any previous isolate. Here, consensus proteins were produced to represent the common physicochemical properties (PCPs) of the epitope rich, B domain of the E2 envelope protein. PCP-consensus proteins were based on multiple strains of VEEV (VEEVcon) and CHIKV (CHIKVcon) or the conserved PCPs of 24 different alphaviruses (AllAV(con)). The AllAV(con) was altered to include binding sites for neutralizing antibodies of both VEEV and CHIKV strains (Mosaik(con)). All four designed proteins were produced solubly in E. coli and purified. They formed the beta-strand core expected from experimental structures of this region of the wild type E2 proteins as indicated by circular dichroism (CD) spectra. Furthermore, the CHIKVcon protein bound to a structure dependent, CHIKV neutralizing monoclonal antibody. The AllAV(con) and Mosaik(con) proteins bound to polyclonal antibodies generated during natural infection with either VEEV or CHIKV, indicating they contained epitopes of both serotypes. The Mosaik(con) antigen induced antibodies in rabbit sera that recognized both the VEEVcon and CHIKV(con )spike proteins. These PCP-consensus antigens are promising starting points for novel, broad-spectrum alphavirus vaccines.

关键词： sweet potato pectin   high hydrostatic pressure   pectinase   physicochemical properties  

摘要： BACKGROUND Sweet potato (Ipomoea batatasL.) is the sixth most important food crop in the world, and China is the largest producer. Large amounts of sweet potato residues are generated during starch extraction, leading to environmental pollution and resource waste. However, these residues can be used as a viable source for pectin extraction. As a natural biopolymer with high molecular weight and complex structure, the usefulness of pectin has been limited, and it needs to be modified in order to improve its physicochemical properties, thus expanding its applications in the food industry. Therefore, the reported study was conducted to modify sweet potato pectin (SPP) using high hydrostatic pressure (HHP) and/or pectinase treatment, and to determine the effects of such treatment on structural, physicochemical and emulsifying properties. RESULTS The results demonstrated that the molecular weight of SPP decreased following HHP and pectinase treatment, which was evidenced using scanning electron microscopy and atomic force microscopy. The degree of esterification was also decreased, confirmed by decreased intensity of the peak at 1739 cm(-1)in the Fourier transform infrared spectrum and decreased peaks at 3.6 and 3.8 ppm in the(1)H NMR spectrum. Moreover, the content of monosaccharides and uronic acids increased and emulsifying properties improved after HHP and pectinase treatment. CONCLUSIONS HHP-assisted pectinase treatment could be used as novel technique for the modification of pectin to give better emulsifying properties with great potential for application in the food industry. (c) 2020 Society of Chemical Industry

关键词： ICH   medication cassette reservoir   stability-indicating method   UPLC DAD   ziconotide  

摘要： Objective To determine the physicochemical stability of ziconotide solutions for intrathecal administration in the Medication Cassette Reservoir (MCR). Materials and Methods A stability indicating UPLC-DAD method was developed and validated according to the ICH guidelines. Two mixtures of ziconotide (0.40 mu g/mL and 0.60 mu g/mL) stored in MCR stored at 25 +/- 2 degrees C were evaluated for 14 days and compared to the initial observed concentrations. Results The physicochemical stability of the two solutions was demonstrated for two days thanks to relative concentrations, pH measurement, visual inspections, and turbidity assays. A degradation product was observed and increased during the study. Conclusion This study showed a very low physicochemical stability of diluted ziconotide stored at 25 +/- 2 degrees C in the MCR. The intrathecal administration of ziconotide does not seem appropriate with this device for outpatients.

关键词： Chicken meat   Bioactive peptides   Peptide stability   Gastrointestinal digestion   UPLC-MS/MS  

摘要： Chicken breast muscle hydrolysates (CBMHs) could promisingly activate alcohol dehydrogenase (ADH) and ameliorate alcohol-induced liver injury. The aim of this work was to investigate the stability of CBMHs against physicochemical treatments and gastrointestinal digestion simulation. Results indicated that CBMHs showed good stability towards heating (25-121 degrees C), pH treatment (pH 2-12) and remained stable in the presence of NaCl (0.01-2 M) and low concentration of metal ions (0.1 mM Zn2+, Ca2+, Fe2+, and Fe2+). Results from in vitro digestion implied a retained activity of CBMHs after gastric tract, but marked decrease (33.42%) after intestinal tract. UPLC-ESI-Q-ToF-MS/MS analysis together with in silico assessments then revealed that the degradation of hydrophobic peptides (i.e., VAPEEHPTLL, YPGIADRM, ADGPLKGIL, and KDLFDPVIQ) during simulated intestinal digestion may be account for the decreased activity. Conformational changes of ADH upon hydrophobic interaction with synthetic peptides were further confirmed by fluorescence quenching study, possibly responsible for the enhanced ADH activity. Hence, CBMHs noticeably showed good stability against physicochemical treatments and digestion simulation, while attempt establishing the structure-activity relationship of peptides is also fundamental before applying CBMHs as functional ingredient.