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关键词： Cilnidipine   PLGA   Polymeric nanoparticles   Plackett-Burman design   Rotatable central composite design   Pharmacokinetic study  

摘要： Cilnidipine (CND) is known to have low oral bioavailability due to its poor aqueous solubility, low dissolution rate, and high gut wall metabolism. In the present study, CND-loaded PLGA nanoparticles (CND-PLGA-NPs) were prepared with two different grades of PLGA (50:50 and 75:25) by design of experiment. Critical factors affecting particle size and entrapment efficiency (EE%) were assessed by mixed design approach, comprising of Plackett-Burman design followed by rotatable central composite design. Particle size, PDI, zeta potential, and EE% of optimized formulations of CND-PLGA(50:50)-NPs and CND-PLGA(75:25)-NPs were 211.6 +/- 1.8 nm, 0.21 +/- 0.05, - 15.1 +/- 1.6 mV, and 85.9 +/- 1.5% and 243.5 +/- 2.4 nm, 0.23 +/- 0.06, -19.6 +/- 1.3 mV, and 92.0 +/- 1.2% respectively. No significant changes were observed in physical stability of NPs when stored at 25 degrees C/60% RH over a period of 3 months. Pharmacokinetic studies revealed that F-abs of CND-PLGA(50:50)-NPs (1.15) and CND-PLGA(75:25)-NPs (2.23) were significantly higher than the free CND (0.26). The C-max and AUC(0-infinity) of CND-PLGA(50:50)-NPs (787.42 +/- 27.38 ng/mL and 9339.37 +/- 252.38 ng/ml x h) and CND-PLGA(75:25)-NPs (803.49 +/- 19.63 ng/mL and 18,153.34 +/- 543.05 ng/ml x h) were significantly higher (p < 0.0001) compared with free CND (367.69 +/- 47.22 ng/mL and 2107.95 +/- 136.40 ng/ml x h). MRTOral of CND-PLGA(50:50)-NPs (33.36 +/- 0.48 h) and CND-PLGA(75:25)-NPs (48.37 +/- 0.61 h) were significantly higher (p < 0.0001) compared with free CND (4.69 +/- 0.58 h). CND-PLGA-NPs can provide higher and sustained plasma drug levels of CND and be effective in antihypertensive therapy.

关键词： Daucus carotaL   turkey meat   food design   color parameters   fatty acids   chemometrics  

摘要： BACKGROUND This study evaluated the modification of physicochemical characteristics and fatty acid composition of fresh turkey sausages manufactured including carrot (Daucus carotaL.) as a vegetable source (i.e., 10%, 20% and 30%, w/w). RESULTS The results were compared with sausages used as controls (i.e., containing 100% turkey meat, w/w). Overall, significant differences were detected for all of the evaluated attributes. The inclusion of 20% and 30% carrot (w/w) in the sausages resulted in a reduction of the lipid content (by 5.42 and 5.26 g/100 g, respectively) and reduced energy value (-7.6%). The color parameters were strongly affected by the inclusion of carrot, recording a significant increase in both redness and yellowness. A reduction of Na content (-47.4% on average) was also observed when experimental carrot sausages were compared with control sausages. Interestingly, a significant reduction in then-6/n-3 fatty acids ratio was also detected. A multivariate orthogonal projection to latent structures discriminant analysis (OPLS-DA) applied to the parameters studied here suggested that the inclusion of carrot provided completely different nutritional and physicochemical profiles, with color parameters possessing the highest discrimination potential. CONCLUSION Including carrot in turkey sausages could represent a valuable tool to design healthier meat products. (c) 2020 Society of Chemical Industry

关键词： Bamboo fiber   Steam explosion   Alkali treatment   Physicochemical   Thermal  

摘要： Bamboo is an abundant natural resource in Asia and one of the high potential fibers used to reinforce polymer composites. This article presents a comparative study on the physicochemical and thermal properties of bamboo fiber (BF) from Gigantochloa scortechinii for untreated BF, steam explosion (SE) treatment BF, and steam explosion followed by alkali (SE-alkali) treatment BF. The physicochemical and thermal properties of BF were determined using energy dispersive X-ray (EDX) spectroscopy and thermogravimetric analysis (TGA), while scanning electron microscopy (SEM) was used to examine the surfaces morphologies. A Fourier transform infrared (FTIR) spectroscopy was utilized to detect the presence of functional groups. TGA results showed that SE BF was significantly more thermally stable than the untreated BF and SE-alkali treatment BF. Major changes in chemical composition and surface morphology of the bamboo fibers indicated that hemicellulose and lignin were removed by SE-alkali treatment. In conclusion, the BF surface is physically and chemically modified by the SE-alkali treatment.

关键词： Cyclodextrins  

摘要： This study was carried out to investigate the effects of popping on properties of makhana (Euryale ferox) seed. The popping was done by initial roasting 270-280 degrees C, tempering (48 hr), final roasting 260-270 degrees C. Popping changed the matrix of makhana from loose crystalline to highly porous structure with increased (p < .05) water (376.24%) and oil absorption capacities (317.16%). A significant (p < .05) increase in the protein and dietary fiber content, whereas a decrease (p < .05) in the amylose, amylopectin content was found. The mineral profile of makhana was not affected during popping, however, a reduction (p < .05) in the iron content was noticed. Phytic acid and tannins were not detected in the popped makhana. The bran obtained during popping showed higher (p < .05) DPPH radical scavenging activity (76.3%). The bran showed higher dietary fiber (83.3%), phenolic (49.0 mg/g), and flavonoid (192.2 mg/100 g) contents. Practical application Popping of makhana enhanced protein content and dietary fiber content. Carbohydrate, starch, amylose, and amylopectin also decreased during popping. The majority of beneficial phytochemicals were concentrated in the bran which was a by-product of popping process. Therefore, the bran may be considered for its application in food products, whereas the raw kernel may be used for incorporation in food products to enhance mineral and amino acid profile.

关键词： Gasification reaction   Carbon conversion   Gasification endothermicity   Char combustion  

摘要： The synthetic effect of H2O on the combustion characteristics of coal char is complicated due to its thermal (high volumetric heat capacity), chemical, and dilution (thereby low oxygen concentration) effects. To assess the impact of these factors on the carbon consumption process, we conduct a quantitative study on the net effect of H2O gasification through experimental and kinetic research. The experiment research is performed at 1773 K in a high-temperature drop tube furnace. The thermal effects of H2O are stripped off the net effect by introducing Ar into the bulk gas to neutralize its high heat capacity. We assess the chemical effects of gasification (gasification endothermicity, and its additional carbon consumption) for a 100 mu m coal char particle reacting in environments of varying O-2, H2O, and Ar using a self-developed char burning kinetics model. The relative contributions of H2O gasification and oxidation to carbon consumption are also discussed. Results indicate that the reduced carbon consumption through the negative effect of gasification (e.g., thermal effects and the gasification endothermicity) exceeds the additional carbon consumption from gasification reaction in the early combustion stages (< 0.3 s), but it is surpassed by the latter with char consumption. Increasing both the concentrations of H2O and O-2 favor the gasification endothermicity. The reduced carbon conversion ratio caused by the endothermicity effect increases as high to around 0.4 then drops down with char consumption. Besides, in the 15 vol.% O-2 case, an increase in H2O concentration from 5 vol.% to 30 vol.% improves the gasification contribution from 22.9% to 46.6% in the middle stage of combustion. It also widens the particle temperature gap by endothermicity effect to over 60 K, but the gap narrows in the burnout stage. Similar results were found in the air-fired case. The relative contribution from H2O gasification reaction is less influential upon the rise of oxygen concen

关键词： Arthrospira platensis   Encapsulation   Food-ink   Functional food   3D printing  

摘要： In the last few decades, consumers' growing attention to the close relationship between health and nutrition is emerging as a new trend, mostly regarding the incorporation of natural ingredients into food. Among those ingredients, microalgae are considered as innovative and promising compounds, rich in valuable nutrients and bioactive molecules. In the present work, 3D printed cookies were fortified with the microalga Arthrospira platensis aiming at developing a new functional food with antioxidant properties. A. platensis antioxidants were recovered using ultrasound-assisted extraction in hydroalcoholic solutions. Ethanol/water and biomass/solvent ratios were optimised through a Design of Experiments (DOE) approach, using the antioxidant activity (ORAC and ABTS) and total phenolic content (TPC) as response variables. The highest ORAC, ABTS and TPC values were observed in the extract obtained with 0% ethanol and 2.0% biomass;thus, this extract was chosen to be incorporated into a printable cookie dough. Three different incorporation approaches were followed: (1) dried biomass, (2) freeze-dried antioxidant extract and (3) antioxidant extract encapsulated into alginate microbeads to enhance the stability to heat, light, and oxygen during baking and further storage. All dough formulations presented shape fidelity with the 3D model. The cookies had a(w) values low enough to be microbiologically stable, and the texture remained constant after 30 days of storage. Moreover, the extract encapsulation promoted an improvement in the ORAC value and colour stability when compared to all other formulations, revealing the potential of A. platensis for the development of a functional 3D food-ink.

关键词： Hyperthermal stress   Acidotic stress   Ruminal fermentation   16S rRNA bacteria   Archaea  

摘要： The drop of ruminal pH and heat are common physicochemical stressors challenging ruminal microbiota, nutrient digestion and cattle performance. We characterized the ruminal microbiota and digestive activity in response to different pH (6.0 and 6.6) and temperature (39.5 and 42 degrees C), as well as established the effective dose of alkaloid supplementation (0, 0.088 and 0.175% of feedstock DM) to modulate ruminal fermentation under these conditions. The acidotic condition decreased microbial diversity and abundances of minor bacterial families whereas most of the highly abundant families like Lactobacillaceae, Prevotellaceae, and Bifidobacteriaceae thrived under the stress. Abundances of all three methanogenic archaea taxa detected increased with heat, as did methane production. However, while Methanomassiliicoccaceae benefited from the low pH, Methanomicrobiaceae diminished and methane production decreased. The low dose of alkaloid addition shifted the fermentation to more propionate and less acetate and the high dose decreased methane and ammonia concentration under the low pH. In conclusion, physicochemical stressors shape the microbial community and function. Mixed alkaloid supplementation facilitates the activity of rumen microbial community under acidotic stress. (C) 2020 The Authors. Published by Elsevier Ltd.

关键词： Copper complexes   Pyrazole-type ligand   Thermal properties  

摘要： Four new coordination compounds of Cu(II) were synthesized with ethyl-5-amino-1-methyl-1H-pyrazole-4-carboxylate (L) and different co-ligands. In the reaction of warm methanolic solutions of CuX2 center dot nH(2)O (X = Cl, n = 2;X = Br, n = 0;X = NO3, n = 3) and the ligand in mole ratio 1:2, bis(ligand) complexes Cu(L)(2)Cl-2 (1), Cu(L)(2)Br-2 (2) and Cu(L)(2)(NO3)(2) (3) were obtained. Unlike this, reaction of CuCl2 with the ligand in the presence of LiOAc yielded to the formation of dimeric complex of the formula [Cu(L)(OAc)(2)](2) (4), with four acetate ions as bridging ligands. In all these complexes, ligand L is coordinated in a monodentate manner through N2 nitrogen atom. The coordination environment in the dimeric complex is octahedral, while in the monomeric complexes the central atom is tetra-coordinated. The molar conductivity data in DMF show that the acetate ions in the dimeric complex are coordinated even in solution. In the monomeric compounds, the molar conductivity data increase in the order 1 < 2 < 3. Since the applicability of the coordination compounds depends on their thermal properties, the thermal decomposition of the complexes was followed by simultaneous TG-DSC measurements. The thermal stability of the monomeric compounds in flowing argon increases in the reverse order as the molar conductivity data. The course of the decomposition is different in the case of the nitrato-compound (3). The decomposition of 3 is followed by a strong exothermic heat effect due to the presence of nitrate ion which is a strong oxidation agent. The decomposition of the other complexes is endothermic, taking place in more or less overlapped reactions. The decomposition of the compounds is completed to 600 degrees C.

关键词： Chitosan   Silver vanadate   Composites   Photodegradation   UV irradiation   Photooxidation  

摘要： Chitosan-AgVO3 nanocomposites were synthesized via ordinary solution casting route at ambient room temperature. During UV prolonged irradiation, the structural and chemical changes were investigated using UV-Vis spectroscopy, Fourier transform infrared (FTIR) and X-ray diffraction analysis (XRD). Spectroscopic exploration of FTIR and UV-Vis indicated the photodegradation processes of prepared thin films. UV-Vis analysis confirmed the generation of new chromophoric groups after prolonged UV irradiation of synthesized lamellar nanocomposites polymer system probably assigned to photooxidation processes. The level of changes of such physicochemical characteristics may be considered to be dependent on the reactive functional groups on the chitosan surface, concentrations of inorganic lamellar dopant (AgVO3 nanorods), irradiation conditions and the time of UV irradiation. Primarily, this study provides the influential modification of chitosan with AgVO3 nanorods.

关键词： Protein aggregation   Yolk globules   Gelation   LF-NMR   Oil exudation  

摘要： To characterize the process of salting in quail eggs, the effects of different curing times on the physical and chemical properties, texture, and microstructure of the eggs were evaluated using conventional analytical methods. Three different types of protons were found in quail eggs qualitatively analyzed by low-field nuclear magnetic resonance (LF-NMR) and imaging (MRI). With an increase in salting time, the moisture content of the yolks showed a decreasing trend, from 452 to 278 g/kg. The salt content of the egg white increased from 7.2 to 26.9 g/L and from 0.8 to 11.9 g/L in egg yolk. Immersion in NaCl changed the structure of the egg yolk protein and destroyed its thermal stability, as well as increasing oil exudation after heating and the number of granular aggregates in the microstructure of the egg yolk. Scanning electron microscopy (SEM) showed that Na thorn induced the aggregation of egg white protein, which destroyed the three-dimensional network structure of the egg white gel, and gradually caused the aggregation of egg yolk protein. Ultimately, this lead to the solidification of the yolk, which changed the shape of the spherical egg yolk particles, resulting in a gritty texture.