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关键词： Meat processing   Meat systems   Meat ingredients   Tropical flour   Extrusion  

摘要： The objective was to determine structural and physicochemical properties of beef emulsion modeling systems prepared with native breadfruit flour and four different extruded breadfruit flours. Extrusion conditions for the flours were summarized as two different specific mechanical energies (74 or 145 kJ/kg) and four unique melt temperatures (83 degrees C, 100 degrees C, 105 degrees C, or 126 degrees C). Meat emulsions formulated at 3% replacement of beef with native or extruded breadfruit flours were compared with control (no additional flour) formulations. Replacement of beef with breadfruit flour (either native or extruded) did not significantly change cooking loss or instrumental redness values of cooked meat emulsions. Interestingly, replacement of beef with the fully gelatinized extruded breadfruit flours altered viscosity during heating as indicated by lower values for storage modulus (44.75% to 62.53% decrease compared with control) and lower values for loss modulus (25.90% to 52.54% decrease compared with control). This resulted in meat emulsions with a significant reduction in textural hardness (28.78% to 37.62% decrease compared with control).

关键词： Dendritic structures   Porosity   Basic strength   Basic sites   CO2 affinity  

摘要： This work investigates the effectiveness of FS loaded with CaO, MgO, and CeO2 for CO2 adsorption. Different techniques such as XRD, ATR-FTIR, Raman, CO2-TPD, in situ FTIR, FESEM, and TEM were employed. Upon the metal oxides loading, the alteration of textural properties, increases in the weak and moderate basic strength and quantity of basic active sites as well as disappearance of the dendritic structures in CaO/FS were observed. The in situ FTIR studies confirmed the formation of different carbonates species upon the interaction with CO2. The greatest CO2 physisorption capacity was demonstrated by CaO-FS (0.76 mmol/g), while the highest CO 2 chemisorption uptake was shown by MgO-FS (9.77 mmol/g). The CO2 physisorption activity depends mainly on the porosity and basic strength of the adsorbents. On the contrary, the CO2 chemisorption performance is determined by the basic strength and basic sites as well as CO2 affinity of the adsorbents.

关键词： Dilute magnetic semiconductor   Rietveld refinement   Magnetism   Photoluminescence  

摘要： This paper investigates the physicochemical properties of rare earth metal Dysprosium (Dy) doped SnO2 dilute magnetic semiconducting nanoparticles. Sol-gel method was adopted to synthesize Sn(1-x)DyxO2 (x = 0, 0.05 and 0.10) compositional series. Structural analysis revealed that all the compositions exhibit pure rutile type tetragonal crystal structure with space group P4(2)/mnm as manifested by Rietveld refinement without any secondary phases and impurities. FTIR spectra of all the compositions showed a band at 592 cm(-1) belonging to Sn-O symmetric vibration. Pure and Dy3+ modified SnO2 nanoparticles exhibited pseudo-spherical morphology with an average particle size of 16 nm, 19 nm, and 22.8 nm for x = 0, 0.05, and 0.10, respectively as calculated from the statistical bar graph distribution of particles. The particle size increased with increasing Dy3+ concentration. The enhancement in cell volume with increasing Dy3+ concentration as calculated from Rietveld refinement studies also complimented TEM results. HRTEM fringe pattern and ring pattern of SAED plot endorsed the formation of tetragonal structure of Sm(1-x)DyxO2(x = 0, 0.05 and 0.10) nanoparticles. Photoluminescence spectra of all the compositions displayed a strong emission peak of similar to 407 nm, which may be ascribed due to oxygen vacancies in the samples. MH hysteresis loop of pure SnO2 showed weak ferromagnetism at low fields and diamagnetic nature at the higher field but Dy3+ doped SnO2 nanoparticles displayed paramagnetism at x = 0.05 and ferromagnetism at x = 0.10, which might be due to increase in oxygen vacancies upon increasing aliovalent Dy3+ in the host SnO2.

关键词： Passion fruit   Foam mat drying   Phenolic acids   Vitamins   Antioxidant  

摘要： The aim of the present study was to develop purple passion fruit powder using the foam mat dried process. The possible effect of whipping time, methylcellulose concentration, and drying temperature on physicochemical and phytochemical properties of foam mat dried passion fruit was evaluated and compared with fruit pulp. The drying process was optimized using central composite design and optimum conditions were whipping time 2.78 min, methylcellulose 2.58%, temperature 44.05 degrees C. At the optimum condition vitamin C, total phenolic compound and hygroscopicity were 34.67 mg/100 g, 258.12 mg GAE/100 g, and 21.12%, respectively. The artificial neural network was applied to predict experimental outcomes. The phytochemical properties in terms of (+/-)-alpha tocopherol, D-alpha-tocotrienol, beta-carotene, and phenolic acid were determined using RP-HPLC. The foam mate dried powder contained a higher amount of beta-carotene (13.26 mg/100 g), total phenolic compound (258.12 mg/100 g) and phenolic acids than fruit pulp whereas fruit pulp was contented higher amount of (+/-)-alpha tocopherol (171.1 mg/100 g) and D-alpha-tocotrienol (27.19 mg/100 g). The study manifested foam mate drying as an effective way to develop passion fruit powder.

关键词： G protein-coupled receptor 116 (GPR116)   Triple-negative breast cancer (TNBC)   Molecular docking   Pharmacokinetic properties  

摘要： G protein-coupled receptor 116 (GPR116), an orphan adhesion receptor, found an important role in cell adhesion and migration in eukaryotes. Abnormal expression of GPCR identified in various cancers turns focus of research community towards GPCR to identify the targeting drug against GPCR. Though GPR116 role was studied in progression of metastasis in triple-negative breast cancer (TNBC), unfortunately, still no drugs targeting GPR116 were identified. TNBC is a hormone-negative aggressive breast cancer found even in young women. Since TNBC has no target receptor for therapy, it would be desirable to target GPR116. Currently, chemotherapy is the only promising option for TNBC;however, these drugs cause chemoresistance. Hence this current study concentrated on finding drugable natural phytochemical ligands targeting GPR116 using in silico approach. Best docked ligand with target and active binding site amino acids were identified in molecular docking study. Pharmacokinetic properties (ADME) were assessed by Qikprop. Result showed that pharmacokinetics properties of natural phytochemicals were as good as existing chemotherapeutic cancer drugs. This study indicates that phytochemicals could be a promising target for GPR116. This in silico analysis facilitates further research to design the drug targeting GPR116 for treatment of TNBC. [GRAPHICS] .

关键词： chlorhexidine   endodontic sealer   antibacterial activity   planktonic bacteria   biofilm   physicochemical properties   surface characterization  

摘要： Objectives. Assess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation. Methods. The antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S. mutans, *** and *** in vitro. The setting time, wettability, microhardness and surface roughness were also assessed. The sealers were studied in no contact, 1-minute (short-term) and continuous contact (long-term) with CHX. Chemical characterization of sealers was performed by scanning electron microscopy, X-ray diffraction analysis and Fourier-transform infrared spectroscopy after CHX or saline used as the last irrigant in an ex vivo tooth model and in endo training blocks. Results. CHX increased the antibacterial activity of all the sealers investigated against planktonic bacteria and biofilms with PCS exerting the highest antimicrobial activity with and without the presence of CHX. The setting of AH Plus and BioRoot RCS was retarded, while for PCS accelerated in the presence of CHX. AH Plus and PCS were more hydrophilic after contact with CHX, whilst BioRoot RCS was hydrophobic in a time-dependent manner. The microhardness of sealers was compromised and the surface roughness increased after CHX exposure for AH Plus and BioRoot RCS, and decreased for PCS. CHX did not affect the sealers' chemistry, but PCS that exhibited two extra phases. Significance. CHX improved the antibacterial efficacy of endodontic sealers but further evidence is needed to confirm its suitability as a final irrigant prior to root canal obturation. (C) 2020 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

关键词： Glass transition  

摘要： The physicochemical, thermal, and dynamic flow properties of ice cream powder were evaluated at different moisture contents. Particle size distribution increased and span decreased considerably as moisture increased. The adsorption isotherms were sigmoid-shaped and could be classified as Type II. Similarly, powder densities increased, while the angle of repose decreased. With increasing moisture content from 3% to 9%, the reduction in glass transition (T-g) from 50.29 degrees C to 32.28 degrees C and sticky point temperature (SPT) from 37.8 degrees C to 14.3 degrees C suggested that caking could occur easily. The basic flow energy and shear tests proved that ice cream powder would flow easily at 3% moisture content than at 9%. Compressibility and wall friction tests also corroborated the fact that ice cream powder was very cohesive at 9% moisture, manifesting difficulties in flow. It became evident that control of interactions of constituents with ambient relative humidity requires the management of storage conditions. Based on SPT, moisture sorption behavior, and dynamic flow properties, the recommended storage conditions for ice cream powder would be 25 degrees C and less than 40% RH (should not exceed 60% RH during storage). Practical applications Powders are inherently complex as many factors influence their behavior during handling and storage. Moisture is the most important of them as it shapes the particle to particle interactions through the formation of strong capillary bridges and overall cohesiveness of the powder. Powders are thus dynamic systems, whose behavior drastically changes with minor modifications in moisture. In this study, the influence of moisture on physicochemical, thermal, and flow properties of ice cream powder was evaluated. The pragmatic approach for characterizing ice cream powder and its flow properties could be useful in understanding its behavior during handling, packaging, and storage. Also, the determination of moisture sorption b

关键词： Malaxation   Olive oil quality   Health claim   Electronic tongue   Chemometrics  

摘要： Olive oil is consumed worldwide due to its appreciated sensory attributes and health benefits, which are related with its fatty acid profile and richness in phenolic compounds that support a health claim concerning olive oil protective effects on blood lipids. However, to ensure that oils possess a rich phenolic content, the extraction conditions can be optimised. Therefore, the effects of malaxation temperature (22, 28 and 34 degrees C) on the physicochemical and sensory characteristics of cv. Cobrancosa olive oils were evaluated. The oils extracted at 22 degrees C had an overall better physicochemical quality (higher total phenols content, greater oxidative stability, lower free acidity and oxidation markers) and more intense positive sensory sensations (higher bitterness and pungency). Additionally, this study showed that a potentiometric electronic tongue could be used to discriminate oils taking into account the effect of malaxation temperature on the overall physicochemical and sensory scores (all samples correctly classified for leave-one-out cross-validation) with a predictive classification similar to that achieved by trained panellists. This finding strengthens the hypothesis that this device could be used as a complementary/alternative taste tool for assessing the impact of the extraction conditions on the oils' physicochemical and sensory characteristics.

关键词： Opuntia species   Prickly pear fruits   Sensory profile   Nutritional value   Protein profile   Potential functional properties  

摘要： Mexico presents the highest richness of Opuntia Mill. species. These species are an important economic factor for the country, and source of nutrients, bioactive compounds, pigments, and nutraceuticals which can be of interest for the food and pharmaceutical industry. However, there are some wild Opuntia species in the Chihuahua desert, that have not been analyzed to establish their properties and potential use. The aim of study was to evaluate the sensory, physicochemical and protein profile in wild prickly pear fruits (O. macrocentra Engelm. (OM), O. phaeacantha Engelm. (OP), and O. engelmannii Salm-Dyck ex Engelmann. (OE)) from Samalayuca, Chihuahua and compare them with two commercial prickly pear fruits (O. ficus-indica (L.) Mill. (green-OFG, red-OFR). The sensory profile of wild species was characterized by highest color, odor, and sour taste compared to the commercial fruits. Pulp, peel, and seeds from wild prickly pear fruits showed lower pH, and higher titratable total acidity, total phenolic compounds, total flavonoids, antioxidant capacity, protein, lipids, ash, carbohydrates (only peel), and crude fiber content than commercial Opuntia species. Furthermore, O. engelmannii showed a tendency to present the highest betacyanins, betaxanthins, and betalains contents. A total of 181, 122, 113, 183 and 140 different proteins were identified in OM, OP, OE, OFG, OFR species, respectively. All species showed the highest enrichment in three main pathways such as amino acids biosynthesis, glycolysis (dark)/gluconeogenesis (light), and the citric acid cycle. The wild prickly pear fruits of this study showed important nutritional, protein, and antioxidant properties with biological interest, and can be a potential source of functional ingredients and nutraceuticals.

关键词： Biodegradable packaging   irradiation   mushrooms   physicochemical properties   polysaccharides  

摘要： The effects of ultraviolet (UV)-C irradiation on the physicochemical properties of oyster mushroom polysaccharide (OMP) films were investigated. The prepared OMP films were subjected to UV-C treatment (5.4 kJ m(-2)). UV-C irradiation increased the tensile strength and decreased the water vapour permeability of the OMP films. In addition, the incorporation of 1.0%Cudrania tricuspidataleaf extract (CTLE) enhanced the antioxidant activity as well as antimicrobial activity of OMP films;however, UV-C treatment did not affect the activities of films containing CTLE. Furthermore, UV-C-irradiated films had higher contact angles than non-irradiated films, indicating increased surface hydrophobicity. Microstructural imaging revealed that UV-C treatment caused the surface of treated films to be smoother than that of untreated films owing to surface degradation. These results indicated that UV-C irradiation can be used for OMP films to improve film properties that are associated with application of films as food packaging material.