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关键词： Microcomputed tomography   Physicochemical analysis   Molded pellet biochar   Pyrolysis temperature   Mechanism  

摘要： To further explain effects of pyrolysis temperature on physicochemical properties of corn stalk pellet biochar from a new perspective, various lab physicochemical analysis methods combining microcomputed tomography were used to characterize biochar in this study. The results showed that at pyrolysis temperatures from 300 degrees C to 800 degrees C, yield of biochar decreased logarithmically with increasing pyrolysis temperature (T);changes of proximate and elemental compositions all showed significant differences, but the change rules were not consistent;high temperature pyrolysis biochar had high stability, high hardness and was convenient for storage and transportation;the proportions of hydroxyl group and amino group were highest in BC800 and BC600, respectively, contributing to the adsorption and removal of pollutants;BC400 had the best combustion performance;X-ray mean attenuation coefficient (XMAC) showed the following correlations, namely, XMAC = 0.003*ln(T-285.329) + 0.011 (R-2 = 0.904) and XMAC = -0.031*(VM/100) + 0.021*(Ash/100) + 0.027 (R-2 = 0.915). Above results provide important basic data support for development of corn stalk pellet biochar.

关键词： Lingzhi (Ganoderma lucidum)   drying   microwave extraction   pulsed electric field   polysaccharide   triterpene  

摘要： Lingzhi (Ganoderma lucidum) is a high-potential mushroom which is used as a dietary supplement or a source of nutrients and antioxidant agents. The aims were to investigate the effect of drying conditions (hot air and vacuum dry) and to compare the extraction methods of microwave-assisted extraction (MAE) and pulsed electric field extraction (PEF) for obtaining triterpenes, flavonoid and polysaccharides. The favourable drying condition was 80 degrees C for 1 h and 37 min, which achieved 1.17 +/- 0.05 mg quercetin/g of flavonoids and 11.49 +/- 0.87 mg ursolic acid/g of triterpenes. The MAE condition was 800 W, 1 min 30 s extraction time and 65.35% ethanol, achieving polysaccharides of 13.08 mg glucose/g and triterpenes of 9.15 mg ursolic acid/g. Additionally, MAE was significantly more efficient than reflux and PEF methods. The application of microwave radiation is beneficial in saving time and solvent and also provides high extraction efficiency for dried Lingzhi.

关键词： conformation   packing energy balance   crystal morphology   inter-molecular packing   lattice energy   molecular conformational deformation energy   particle surface energy   Ritonavir   solvent selection   surface chemistry  

摘要： Purpose Application of multi-scale modelling workflows to characterise polymorphism in ritonavir with regard to its stability, bioavailability and processing. Methods Molecular conformation, polarizability and stability are examined using quantum mechanics (QM). Intermolecular synthons, hydrogen bonding, crystal morphology and surface chemistry are modelled using empirical force fields. Results The form I conformation is more stable and polarized with more efficient intermolecular packing, lower void space and higher density, however its shielded hydroxyl is only a hydrogen bond donor. In contrast, the hydroxyl in the more open but less stable and polarized form II conformation is both a donor and acceptor resulting in stronger hydrogen bonding and a more stable crystal structure but one that is less dense. Both forms have strong 1D networks of hydrogen bonds and the differences in packing energies are partially offset in form II by its conformational deformation energy difference with respect to form I. The lattice energies converge at shorter distances for form I, consistent with its preferential crystallization at high supersaturation. Both forms exhibit a needle/lath-like crystal habit with slower growing hydrophobic side and faster growing hydrophilic capping habit faces with aspect ratios increasing from polar-protic, polar-aprotic and non-polar solvents, respectively. Surface energies are higher for form II than form I and increase with solvent polarity. The higher deformation, lattice and surface energies of form II are consistent with its lower solubility and hence bioavailability. Conclusion Inter-relationship between molecular, solid-state and surface structures of the polymorphic forms of ritonavir are quantified in relation to their physical-chemical properties.

关键词： Nanoemulsions   Physicochemical properties   Quillaja saponin   Salad dressing   Whey protein isolate  

摘要： The impact of curcumin-loaded nanodroplets on the properties of commercial salad dressings was examined. Nanoemulsions were formulated using a plant-based oil (medium chain triglycerides, MCT) and either a plantbased (Quillaja saponaria, QS) or animal-based (whey protein isolate, WPI) emulsifier. Curcumin-loaded nanoemulsions produced by microfluidization contained small anionic oil droplets: d32 = 0.28 and 0.11 mu m and zeta = -45 and -42 mV for QS and WPI, respectively (pH 7). The dressing contained larger oil droplets (d32 = 7.8 mu m) with a lower negative charge (zeta = -23 mV). The zeta-potential of the dressing was positive under acid and negative under neutral conditions, suggesting the oil droplets were coated by proteins. At pH 3.4, adding QSnanoemulsions to the dressing reduced the positive charge, but adding WPI-nanoemulsions increased it. The presence of the nanoemulsions decreased the mean particle diameter of the dressing. Incorporation of nanoemulsions (0-30 g/100 g) reduced the viscosity of the dressings, probably because of the reduction in fat content and ability of small oil droplets to get between larger ones. Finally, incorporation of curcumin-loaded nanoemulsions gave the dressings a strong orange/yellow color (negative a*, positive b*) due to selective light absorption by curcumin.

关键词： Optical and Electronic Materials   Characterization and Evaluation of Materials  

摘要： In this work, Fe3O4@ZnFe2O4 core/shell nanoparticles were obtained by depositing ZnO by the wet chemistry method on the surface of Fe3O4 nanoparticles seeds obtained by the chemical bath deposition method. Fe3O4 and Fe3O4@ZnFe2O4 were characterized by Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Spectrometry, Transmission Electron Microscopy, X-ray Diffraction, Ultraviolet-Visible Spectroscopy, Diffuse Reflectance, and Fourier Transformed Infrared Spectroscopy (FTIR). The Fe3O4@ZnFe2O4 nanoparticles formed an urchin-like spheres morphology (corresponding to Fe3O4) with a homogeneous shell of ZnFe2O4. XRD analysis showed a magnetite crystal structure for Fe3O4 and a franklinite (ZnFe2O4) crystal structure for the shell. Fe3O4@ZnFe2O4 showed higher crystallinity when applying a heat treatment, showing a crystal size of 9.12 nm with heat treatment and 9.43 nm without heat treatment. The diffuse reflectance results suggested an indirect band gap of 1.85 eV for Fe3O4 and two indirect band gaps of 1.85 eV and 2.54 eV for Fe3O4@ZnFe2O4. The FTIR results showed the effect of heat treatment on Fe3O4@ZnFe2O4 core/shell nanoparticles. A simple method was used for the synthesis of Fe3O4@ZnFe2O4.

关键词： Sonication  

摘要： The present study investigated the effect of sonication alone and sonication with subsequent pasteurization on physicochemical and antioxidant properties of juice extracted from the ripe or overripe wax apple. Samples were sonicated for varying times (0-10 min) at a fixed frequency (28 kHz) and temperature (20 degrees C) and then, pasteurized at 90 degrees C for 2 min. Irrespective of the maturity, sonication improved the color characteristics (lightness, chroma, and hue) of wax apple juices (p > .05). Other quality parameters (titratable acidity, total soluble solids, cloud value and electrical conductivity) exhibited similar changes for all the juice samples tested. Sonicated samples retained higher antioxidant activity (5%-30%), especially in the ripe juice, whereas pasteurization significantly reduced (5%-20%) the antioxidant activity, as well as the total phenolic content. Moreover, sonication significantly reduced the enzyme activities, including polyphenol oxidase, polygalacturonase, pectin methylesterase, and peroxidase by 2%-10% when compared with pasteurization. Overall, sonication, either individually or in conjunction with pasteurization or thermal processing, was beneficial for maintaining the quality by inactivating enzymes, and retaining nutrients, whereas pasteurization degraded these juices. Novelty impact statement Ripe and overripe wax apple fruit juice was treated by pasteurization and sonication. Sonicated ripe wax apple juice was found to improve various phytochemical contents and antioxidant activities. Pasteurized and as well as sonicated ripe and overripe wax apple juice were effectively controlled the activities of quality degrading enzymes such as polyphenol oxidase, polygalacturonase, pectin methylesterase, and peroxidase

关键词： Maltodextrin   Plant extract   Phenolic compounds   Ultrasound   Whey protein concentrate   Probiotic yogurt  

摘要： In this study, the effect of free and microencapsulated extract of pennyroyal on the viability of Bifidobacterium bifidum and physicochemical and sensory properties of probiotic yogurt were evaluated. For this purpose, pennyroyal extract (PE) was extracted using ultrasound method. The amount of phenolic compounds of PE was 75.64 +/- 1.25 mg/g gallic acid and the PE was microencapsulated with maltodextrin-whey protein concentrate. According to the results, the particle size was 100.14 nm, zeta potential was 17.44 mV and microencapsulation efficiency was 60.06%. Then, the antioxidant properties of the PE and nano-PE were determined. The results showed that the both of them had high antioxidant properties and the antioxidant activity of nano-PE was significantly higher than the PE (P < 0.05). In order to evaluate the effect of PE on the properties of probiotic yogurt 5 treatments including control, PE and nano-PE with a concentration of 750 and 1000 ppm, production and physicochemical, antioxidant properties, and viability of probiotic bacteria were evaluated during a 15-day storage period. The results showed that adding the PE to yogurt decreased pH, syneresis, and increased acidity, viscosity, and antioxidant properties of yogurt (P < 0.05). At the end of the storage period, the treatments containing the PE had higher viability of probiotic bacteria than the control treatment (P < 0.05). In most cases, better results were observed in the treatments containing nano-PE and also these treatments had a higher sensory score than the treatments containing the PE (P < 0.05). Overall, the results of this study show that microencapsulated of PE can be used to improve antioxidant capacity, probiotic bacterial viability and the quality of yogurt.

关键词： Nizimuddinia zanardini   Alginate   High voltage electrode discharge   Rheology   Emulsion   Antioxidant  

摘要： Alginic acids and alginates have important applications in food, medicine, pharmaceutical industry, dentistry and textile. The sodium alginate from Nizimuddinia zanardini (an Iranian brown seaweed) was extracted with high voltage electrical discharge to investigate the influence of this extraction method on its structural and physico-chemical characteristics. The extracted alginate had a M/G ratio of 1.22, a molecular weight of 119 kDa, a polydispersity index of 2.7 and an intrinsic viscosity of 170.8 mL/g. The rheological properties of an alginate solution (2% w/v) indicated a Newtonian fluid type of behavior. The influence of pH on the flow behavior of this solution was investigated. The solution had a Newtonian behavior at pH 7.0, an intermediary behavior between Newtonian and non-Newtonian shear thinning at pH 6.0 and 5.0 and a clearly shear thinning behavior at lower pH values (4.5 and 3.0). Its antioxidant activity was tested by diphenyl picrylhydrazyl radical scavenging and hydroxyl radical-scavenging activity showing its potential for food preservation. High voltage electrical discharge improved the antioxidant properties explained by the co-extraction of phenolic compounds. The stability of emulsion increased with concentration of alginate and was reported at 94.7% +/- 0.1 at 2% (w/v) concentration. The stability of emulsions was not affected by temperatures up to 55 degrees C and was resistant to pH changes.

关键词： Mango (Mangifera indica) wine   Mango varieties   Yeast strains   Physicochemical analysis   Functional attributes   Cost-effective  

摘要： Mango (Mangifera IndicaL.) is a major tropical fruit rich in sugar, organic acids and flavonoids, making it suitable fruit for wine making. In the present study, five varieties of mango (Baganpalli,Langra,Dashehari,Alphonso,and Totapuri) were utilized for wine production using two different yeast strains namely,Saccharomyces cerevisiaeMTCC 178 and isolated yeast. The physiochemical analysis of wine produced from chosen mango varieties showed that North Indian local mango variety (Dashehari) gave better results in terms of organoleptic and functional attributes. TheSaccharomyces cerevisiaeMTCC 178 treatedDashehariwine possessed 6.1 +/- 0.26% TSS, 2.1 +/- 0.08% reducing sugar, 0.657% titratable acidity, 0.11 +/- 0.00% volatile acidity, 12% ethanol (v/v) and pH 3.7 +/- 0.10 comparable toBaganpallimango wine. HPLC analysis ofSaccharomyces cerevisiaeMTCC 178 inoculatedDasheharimango wine revealed the presence of primarily;gallic acid (RT-4.4 min), Galloyl-A-type, procyanidin (RT-5.2 min), 2,2,6-Trimethyl-6-vinyltetrahydropyran (RT-8.91 min), beta-Pinene (RT-11.47 min) and Caffeoyl-quinic acid (RT-12.15 min) showing potential antioxidant, anti-cancerous, anti-inflammatory and antimicrobial properties. The local mango varieties wine showed significant (p < 0.05) physicochemical properties, antioxidant potential and ethanol content comparable toBaganpalliwine and was cost effective.

关键词： liquid MPC   heating   pH   functional properties   acid gelation  

摘要： Milk protein concentrates (MPC) are typically dried high-protein powders with functional and nutritional properties that can be tailored through modification of processing conditions, including temperature, pH, filtration, and drying. However, the effects of process -ing conditions on the structure-function properties of liquid MPC (fluid ultrafiltered milk), specifically, are understudied. In this report, the pH of liquid MPC [13% protein (70% protein DM basis), pH 6.7] was adjusted to 6.5 or 6.9, and samples at pH 6.5, 6.7, and 6.9 were subjected to heat treatment at either 85 degrees C for 5 min or 125 degrees C for 15 s. Sodium dodecyl sulfate PAGE was used to determine the distribution of caseins and denatured whey proteins in the soluble and micellar phases, and HPLC was used to quantify native whey proteins as a measure of denaturation, based on the processing conditions. Both heat treatments resulted in substantial whey protein denaturation at each pH, with beta-lactoglobulin denatured more extensively than alpha-lactalbumin. Changes in liquid MPC physicochemi-cal properties were monitored at d 1, 5, and 8 during storage at 4 degrees C. Viscosity increased after heat treatment and also over time, regardless of pH and heating condi-tions, suggesting the role of whey protein denaturation and aggregation, and their interactions with casein micelles. The MPC samples processed at pH 6.9 had a significantly higher viscosity than those heated at pH 6.5 or 6.7, for both temperature and time conditions;and samples processed at 85 degrees C for 5 min had higher viscosity than those heated at 125 degrees C for 15 s. Particle size analysis indicated the presence of larger particles after 5 and 8 d of MPC storage after heating at pH 6.9. Acid-induced gelation of the liquid MPC led to sig-nificantly higher gel firmness after processing at 85 degrees C for 5 min, compared with 125 degrees C for 15 s. Also, gels made from MPC adjusted to pH 6.5 had higher storage moduli, wi