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关键词： zinc oxides   mechanochemical activation   physicochemical properties   triethanolamine  

摘要： The mechanical activation of zinc oxide with the addition of a surfactant (triethanolamine) in mills of two types - roller-ring vibratory and planetary-centrifugal - is examined. The dependences of the specific surface area on the activation time and content of the surfactant are presented and the effect of the mechanochemical activation on the pore-radius distribution, the dispersity of zinc oxide, and the surface morphology is shown. It is shown that the physicochemical properties of activated zinc oxide make it useful for the production of technical ceramic in the form of carriers for the catalysts and adsorbents used in the desulfurization of gases.

关键词： Peat bogs   Metals   Metal mobility   Environmental pollution   North European part of Russia  

摘要： This article is devoted to the study of physicochemical parameters and the assessment of the accumulation and distribution of metals in peat deposits from the North European part of Russia (Arkhangelsk region). Peat profiles were selected both in the area with a high anthropogenic load and in a bog remote from industrial pollution. The determination of metals was carried out by using the methods X-ray fluorescence analysis and atomic absorption spectroscopy. It was determined that the studied bogs can be attributed to the low ash type, and the recorded pH and mineralisation values make it possible to attribute these deposits to the acid-oxidising facies of oligotrophic peatlands, characteristic of taiga landscapes. Assessment of metal accumulation showed a high content of titanium, chromium, lead, nickel, vanadium, cobalt, aluminium, silicon, and copper in peat, mainly caused by the burning of fossil fuels and industrial production, as well as the burning of urban and industrial waste. The peat profiles are characterised by significant fluctuations in the content of elements in different horizons. Studies have shown the need to monitor the content of metals in peatlands from the Arkhangelsk region to assess atmospheric pollution from industrial emissions, both at the moment and in the past.

关键词： margarine   palm oil   puff pastry   food storage   triacylglycerol separation  

摘要： Developing trans-free alternative fat solutions suitable for specific applications remains a challenge in edible fats and other domains. This is particularly true for palm oil-based puff pastry margarines, which suffer from post crystallization problems, leading to dramatic loss of functionality. This research is aimed at investigating the influence of triacylglycerol (TAG) compositions of palm oil-based puff pastry margarines on the physical properties of the fat crystal network, which determine the functionality of such products. Three model puff pastry margarines are produced at pilot scale under the same crystallization conditions. They share the same fatty acid composition and close solid fat content (SFC) profiles, whereas the proportions of major TAG (tripalmitoylglycerol (PPP), 1,3-di-palmitoyl-2-oleoylglycerol (POP), 1,2-di-palmitoyl-3-oleoylglycerol (PPO), 1,2-dioleoyl-3-palmitoylglycerol (POO)) are different. Polymorphism, melting profile, hardness, microscopic structures, and baking performance (puffing effect) of the model fats are examined during a period of 6 months. The following results are obtained: 1) The TAG composition significantly influences the post crystallization processes occurring in palm oil-based margarines. 2) High amounts of POP show negative influences. 3) The proportions of POP, PPO, and PPP should be carefully balanced to prevent detrimental crystal network rearrangements, leading to textural modifications (hardness increase) and significant reduction in baking performance.

关键词： Cystatin   Domain-swapping   Crystallography   Circular dichroism   Analytical ultracentrifugation  

摘要： Phytocystatins are a family of plant cysteine-protease inhibitors of great interest due to their biotechnological application in culture improvement. It was shown that their expression in plants increases resistance to herbivory by insects and improves tolerance to both biotic and abiotic stress factors. In this work, owing to the economical relevance of the source organism, a phytocystatin from hop (Humulus lupulus), Hop1, was produced by heterologous expression in E. coli Lemo21 (DE3) cultivated in auto-inducing ZYM-5052 medium and purified by immobilized metal ion affinity and size exclusion chromatography. Thermal denaturation assays by circular dichroism showed that Hopl exhibited high melting temperatures ranging from 82 degrees C to 85 degrees C and high thermal stability at a wide pH range, with Delta G(2)(5)'s higher than 12 kcal/mol. At 20 degrees C and pH 7.6, the dimeric conformation of the protein is favored according to size exclusion chromatography and analytical ultracentrifugation data, although monomers and higher order oligomers could still be detected in a lesser extent. The crystal structure of Hop1 was solved in the space groups P 2 2(1) 2(1) and C 2 2 2(1) at resolutions of 1.80 angstrom and 1.68 angstrom, respectively. In both models, Hop1 is folded as a domain-swapped dimer where the first inhibitory loop undergoes a significant structural change and interacts with their equivalent from the other monomer forming a long antiparallel beta strand, leading to loss of inhibitory activity.

关键词： Arachin   Basil seed gum   Composite gels   Gel properties   Chemical interaction forces  

摘要： In this study, the effects of basil seed gum (BSG) (0-1%, w/v) on the physicochemical and structural properties of heat-induced arachin gels were investigated. The results showed that the water holding capacity, gel strength, viscoelasticity and thermal stability were improved by increasing the BSG concentration from 0.25% to 1%. The BSG could absorb excessive water around arachin molecules and facilitate the alternation of protein tertiary structures, which were beneficial to protein unfolding, aggregation and gel formation. The result of chemical interaction forces showed that the hydrophobic interaction, electrostatic interaction and hydrogen bond between arachin and BSG were enhanced by BSG and the interactions promoted the formation of a strong three-dimensional gel structure, as well as increased the storage modulus (G'), thus leading to reinforced gel strength. Confocal laser scanning microscopy and scanning electron microscopy exhibited a compact, phase-separated and bicontinuous network of the composite gels with 0.75% and 1% BSG. These findings may pro-vide valuable information for developing novel arachin-based gel products and expanding the practical appli-cations of arachin in the food industry.

关键词： food applications   modified starches   nanoparticles   swelling factor   thermal properties  

摘要： This work aims to understand the physicochemical properties of potato starch nanoparticles (SNPs) obtained by anti-solvent precipitation. Moisture content, water activity, color, morphology, thermal behavior (differential scanning calorimetry), swelling factor, solubility in water, water sorption isotherms, rheological properties, and stability in water are analyzed and compared using native potato starch (PS) as control. The resulting SNPs after anti-solvent precipitation have a particle size between 50 and 150 nm, smaller than those observed in PS (between 10 and 100 mu m). SNPs behave as an amorphous material without gelatinization stage where the swelling factor is drastically reduced, while the solubility increased dramatically at low temperatures when compared with PS. The Guggenheim-Anderson-de Boer model from the isotherms data allows a calculation of the surface area, obtaining values of 105 and 211 m(2)g(-1)for PS and SNPs, respectively. The high surface area in SNPs is associated with an increase in the proportion of hydroxyl groups active for water adsorption throughout its structure. Both samples show Newtonian fluid behavior;however, SNPs solutions prove to be much more stable at room temperature than PS solution.

关键词： androgenetic alopecia   topical minoxidil gel 5%   topical spironolactone gel 1%  

摘要： Topical minoxidil 5% are effective in androgenetic alopecia (AGA). Spironolactone acts as an androgen antagonist by competitively blocking androgen receptors. Studying the effect of topical minoxidil 5% gel and spironolactone gel 1% in management of AGA. The study includes 60 patients diagnosed as AGA;(group I): treated with topical minoxidil gel 5%, (group II): with topical spironolactone gel 1% and group (III) treated with combined minoxidil 5% and spironolactone 1% gel. All patients were followed up monthly throughout the treatment period. Scalp biopsy was taken before and after 12 months. In group I, the clinical response was in 90% of patients with variable degrees in improvement, in group II, the clinical response was in 80% of patients, meanwhile, in group III the clinical response was in all patients (100%). Histopathological examination of skin biopsy after treatment revealed significant increase in anagen hair on the other hand, both telogen and vellus hair was significantly decreased meanwhile, the T/V ratio was significantly increased. The results of this work revealed that topical minoxidil gel 5% and topical spironolactone gel 1% were effective in treatment of AGA, while the combination of two agents was better in treatment.

关键词： Cowpea starch   legumes   modification   physicochemical properties  

摘要： Cowpea is a food legume with high protein and carbohydrate contents, which could be explored in addressing food and nutritional challenges in many parts of the world. However, some cowpea varieties are difficult to cook, resulting in high energy requirements and greater loss of nutrients. Since the bulk of carbohydrate in cowpea is starch, this component may be explored as an alternative starch source for various industrial applications, especially because cowpea starch is rich in resistant starch with several beneficial physiological effects. Hence, this review summarises the present knowledge on the isolation, composition, physicochemical properties and modification methods of cowpea starch. Future studies that are required to produce cowpea starch with novel properties were highlighted and the need to apply modified cowpea starch in food systems were also noted.

关键词： microwave‐   assisted extraction   phenolic compounds   Rosmarinus officinalis L   sensory evaluation   supplemented cheese  

摘要： Rosmarinus officinalis L. leaves can be valorized by their uses in the production of healthy foods. Rosemary powder and its lyophilized ethanolic extract at different concentrations (g/100 g) were used for the formulation of fresh cheeses: powder cheeses (B: 0.25%, C: 0.5%, D: 0.75%), extract cheeses (E: 0.25%, F: 0.5%) and control cheese (A: 0%). The ethanolic extract was obtained under the optimum conditions of microwave-assisted extraction (MAE) using response surface methodology (RSM) coupled with a Box-Behnken design (BBD);the optimum conditions were as follows: ethanol concentration 78.162%, microwave power 351.825W, ratio of solvent to raw material 101.623:1, and extraction time 122.648 s. Physicochemical parameters (pH, proteins, fat) of the formulated cheeses were not affected by this supplementation but the plant extract improved phenolics content and antioxidant capacity when compared to the control cheese. A correlation between physicochemical parameters, antioxidant activity as well as the sensory characteristics was carried out using principal component analysis (PCA). Cheeses C;D and F were most appreciated (60%-80%) by the panelists. Practical applications Rosmarinus officinalis L. is an evergreen branched and bushy shrub, easy to plant by cuttings, with a relevant commercial interest. It is rich in phenolic compounds which are well known for their potential diversified properties and applications. This work demonstrated the possibility of exploiting the optimized microwave-assisted extraction (MAE) technique to obtain, in short time, these valuable antioxidants from rosemary leaves. Among the rosemary applications in foods, are leaves (powder, ethanolic extract) that were incorporated in fresh cheese formulations to provide a distinctive taste, aroma and to act as flavor enhancer for better acceptability by the consumers. The success of these fortified-cheeses is explained by their health benefits (high phenolic contents with high antioxidant capaci

关键词： Coastal ecology   Tropical estuary   Water quality   Pollution   Conservation  

摘要： Estuaries receive the anthropogenic pollutants of their watershed area. Dhamra estuary, on the east coast of India, is such an estuary that receives a huge amount of pollutants, and it will eventually pose a threat to the ecological sensitive areas in its vicinity. Therefore, a study was carried out on physico-chemical parameters and chlorophyll-a to delineate the sources of variation during pre-monsoon and post-monsoon seasons. Surface water sampling was carried out from 12 stations in the estuarine and coastal area. Factor analysis and cluster analysis were applied to seasonal data to understand the sources of variation. From the study, it was observed that the chemical parameters are severely affected by anthropogenic influences such as sediment dredging, aquaculture effluent, and waste from industry and sewage from upstream. In the long run, this will affect the nearby nesting ground of vulnerable Olive Ridley turtles, high bio-diverse mangrove forests, and saltwater crocodile habitat.