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关键词： Powders  

摘要： "Cempedak" is an aromatic fruit, which can be converted into powder with a longer shelf life. The effects of different drying methods (spray-drying, freeze-drying, convection oven-drying, and vacuum-drying) on "cempedak" powders produced were evaluated in their physicochemical properties (moisture content, water activity, wettability, flowability, water solubility index, hygroscopicity, and degree of caking). In addition, the color and antioxidant content (carotenoid and DPPH scavenging activity) of "cempedak" powder were determined as well. The process yield of convection oven-dried "cempedak" powders is higher (62.98%) as compared to spray-dried powder (25.08%). On the contrary, the total color change for freeze-dried powder is lesser (12.31) compared to other drying methods. The scavenging activity of freeze-dried powder had the greatest antioxidant effect, which is 52.12% at 50 mu g/ml, while the carotenoid content of freeze-dried powder is 15.83 mg/g. Freeze-drying can produce higher quality "cempedak" powder as compared to spray-drying, convection oven-drying, and vacuum-drying. Practical applications "Cempedak" is an aromatic fruit that is rich in vitamin A. However, due to the short harvesting season, it can be converted into powder for better stability and longer product shelf life. With the different drying methods available, the powder produced defers in its physicochemical properties. This research compares the "cempedak" powders produced with spray-dryer, freeze-dryer, convection oven, and vacuum oven. With the understanding of the different quality of powders obtained, the food industry will be benefited as to which production method to choose for their powder with the desirable specification. The powder can be used as a functional ingredient.

关键词： Dispersion ability   Food development   Nanocellulose technology   Okara   Specific surface area   Viscosity  

摘要： Okara, the residue of the production of tofu and soybean milk, is rich in dietary fibers (DFs) and phytochemical components such as soy isoflavones (SIs) and soyasaponins (SSs). Despite its nutritive value, okara is scarcely used as a food source as the DFs in okara are mostly insoluble and have adverse effects on food texture. Thus, it is necessary to improve the physicochemical properties of okara. This review presents a detailed investigation on okara food development focusing on nanocellulose (NC) technologies that have progressed in recent years, mainly the Supermasscolloider and Star Burst systems. These NC technologies have increased the dispersion ability, viscosity, and specific surface area of cellulose and okara. Increased viscosity and specific surface area of atomized okara effectively suppressed alpha-amylase activity, and the increased specific surface area and dispersion ability of okara increased the production of short-chain fatty acids by human dominant gut bacteria. In addition, the consumption of cellulose nanofibrils in conjunction with exercise inhibited the obesity induced by high-fat diets by modulating the gut micmbiota balance in mice. Mice experiments indicated that dietary supplementation with SIs and SSs may also have beneficial effects in preventing allergic contact dermatitis, and that the gut microbiota is critical for their therapeutic value. Therefore, frontline technologies for NC will facilitate novel ways to develop healthy foods to prevent obesity and immune-related diseases using okara.

关键词： Biomaterials   Controlled release   Cytotoxicity   Hydrotalcite   NSAID   Structural reconstruction  

摘要： Injured bone tissues can be healed with bone grafts, but this procedure may cause intense pain to the patient. A slow and localized delivery of nonsteroidal anti-inflammatory drugs (NSAIDs) could help to reduce the pain without affecting bone regeneration. The objective of the present study was to use [Mg-Al]-layered double hydroxide (LDH) as a matrix for controlled release of sodium naproxen (NAP). This system could be applied in biomaterial formulations (such as bone grafts) to achieve a local delivery of naproxen. [Mg-Al]-LDH successfully incorporated up to 80% (w/w) of naproxen by the structural reconstruction route, with the [Mg-Al]-LDH interlayer space increasing by 0.55 nm, corresponding to the drug molecule size. The evaluation of the naproxen release kinetics showed that 40% of the drug was delivered over 48 h in aqueous medium (pH 7.4 +/- 0.1), indicating the potential of [Mg-Al]-LDH/NAP for local release of naproxen at adequate concentrations. Kinetic modeling showed that the naproxen release process was closely related to the Higuchi model, which considers the drug release as a diffusional process based on Fick's law. The chemical stability of NAP after the release tests was verified by H-1 NMR. The [Mg-Al]-LDH/NAP also exhibited low cytotoxicity toward fibroblast cells (L929 cell line), without modifications in their morphology and adhesion capacity. These results describe a suitable approach for preparing efficient systems for local delivery of nonsteroidal anti-inflammatory drugs for biomedical applications.

关键词： Ti6Al4V scaffolds   ZrO2 scaffolds   PEEK scaffolds   SaOs-2 cells   Bone tissue engineering  

摘要： Bone is a dynamic tissue with an amazing but yet limited capacity of self-healing. Bone is the second most transplanted tissue in the world and there is a huge need for bone grafts and substitutes which lead to a decrease in bone banks donors. In this study, we developed three-dimensional scaffolds based on Ti6Al4V, ZrO2 and PEEK targeting bone tissue engineering applications. Experimental mechanical compressive tests and finite element analyses were carried out to study the mechanical performance of the scaffolds. Overall, the scaffolds presented different hydrophilicity properties and a reduced elastic modulus when compared with the corresponding solid materials which can in some extension minimize the phenomenon of stress shielding. The ability as a scaffold material for bone tissue regeneration applications was evaluated in vitro by seeding human osteosarcoma (SaOS-2) cells onto the scaffolds. Then, the successful culture of SaOS-2 cells on developed scaffolds was monitored by assessment of cell's viability, proliferation and alkaline phosphatase (ALP) activity up to 14 days of culturing. The in vitro results revealed that Ti6Al4V, ZrO2 and PEEK scaffolds were cytocompatible allowing the successful culture of an osteoblastic cell line, suggesting their potential application in bone tissue engineering. Statement of Significance. The work presented is timely and relevant since it gathers both the mechanical and cellular study of nondegradable cellular structures with the potential to be used as bone scaffolds. This work allow to investigate three possible bone scaffolds solutions which exhibit a significantly reduced elastic modulus when compared with conventional solid materials. While it is generally accepted that the Ti6Al4V, ZrO2 and PEEK are candidates for such applications a further study of their features and their comparison is extremely important for a better understanding of their potential.

关键词： arglabin   arabinogalactan   mechanochemical treatment   mechanical composites   NMR spectroscopy   X-ray diffraction analysis  

摘要： In recent decades, researchers have increasingly turned to natural compounds and preparations created from them. Biologically active terpenoids, in particular, natural sesquiterpene lactones, are of great interest. One of the rich sources of these compounds is a plant of the genus Artemisia, whose representative is wormwood Artemisia glabella Kar et Kir., growing in Central Kazakhstan. In the study of the chemical composition of wormwood, a new biologically active compound, sesquiterpenic lactone arglabin, with antitumor and radiosensitizing properties has been isolated. The antitumor drug "Arglabin" is used in oncological clinics of the Republic of Kazakhstan, Russian Federation, Uzbekistan, the Republics of Georgia, Belarus, Kyrgyzstan and Tajikistan in the complex therapy of tumors of the breast, lung, liver, etc. The purpose of this work is to study the physicochemical properties of mechanically treated arglabin and its mixture with a larch water-soluble polysaccharide arabinogalactan, obtained by mechanochemical means. According to IR, UV and C-13 NMR spectroscopy, long-term mechanochemical treatment does not lead to a change in the chemical composition of arglabin molecules. All the spectra obtained are identical to the spectra of the initial (not mechanically treated) arglabin. Using X-ray analysis, it was shown that in the mechanocomposites of arglabin with arabinogalactan there is no disordering of the crystal structure of arglabin and its molecular dispersion in the polysaccharide matrix does not occur.

关键词： Biodegradable PDMMLAs   Stent coating   Biocompatibility   Biological response   HUVECs   Monocytes adhesion  

摘要： To reduce the risk of intra-stent restenosis and improve hemocompatibility of biomaterials, the therapeutic re-endothelialization is required. Indeed, the behavior of endothelial cells is affected by several factors such as wettability and surface energy of biomaterial in contact with cells and blood. The aim of this study was to evaluate the physicochemical and biological properties of new polymers derived from poly((R,S)-3,3-dimethylmalic acid) (PDMMLA) that will be used as cardiovascular stents coating. In fact, a comprehensive study of the roughness and topography and the thermal and rheological properties of these materials were investigated. Furthermore, this was correlated with the biological response of human vascular endothelial cells (HUVECs) and monocytes (MM6) to these biomaterials. Our results revealed very interesting surface properties of PDMMLAs, excellent thermal and thermo-mechanical properties and a suitable biological response. All these properties can be adjusted by simple chemical modification of the side chain of the studied polymers.

关键词： Steam blanching   Antioxidant   Ultra high performances liquid chromatography   Caffeic acid   Catechin  

摘要： Kenaf (Hibiscus cannabinus) leaves are produced as the by product when kenaf stems were harvested. The kenaf leaves was examed for the applicable possibility as herbal tea due to their rich phenolic content. In this study, the effect of steam blanching and high temperature drying on physicochemical properties, antioxidant activity and consumer acceptability of the kenaf tea leaves were studied. Results showed that steam blanching prior oven-drying improved the extractability of phenolic compounds, leading to the increase in total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, and ferric reducing antioxidant power. Drying at 120 degrees C was able to preserve more phenolic compounds, at the same time developing better taste, mouthfeel, and overall acceptability of kenaf leaves tea. Caffeic acid, tannic acid, catechin, and chlorogenic acid in kenaf tea leaves infusion were analyzed by ultra high performances liquid chromatography. In conclusion, steam blanching prior to 120 degrees C oven-drying was the best process method for the production of kenaf leaves into acceptable tea type.

关键词： Rice starch   Whey protein isolate   Dry heating   Morphology   Structure   Oil-binding ability  

摘要： The effect of dry heating treatment with whey protein isolate (WPI) on the morphological and physicochemical properties of rice starch (RS) was investigated. Scanning electron microscopy results demonstrated that WPI-mediated aggregation of RS granules was more pronounced as the dry heating time increased, which was further confirmed by analysis of the particle size distribution. Differential scanning calorimetry results showed that dry heating treatment in the presence of WPI significantly decreased the gelatinization temperature of RS but without affecting the gelatinization enthalpy change. X-ray diffraction and Fourier transform infrared spectroscopy analysis demonstrated that the long and short range orders of RS were partially damaged following dry heating treatment and the incorporation of WPI. In addition, a significant increase in the oil-binding ability was observed in the dry heated starch samples, which was more pronounced under the combination of dry heating with WPI. These phenomena could be attributed to the interaction of RS with WPI, the aggregation and denaturation of WPI, and the disruption of hydrogen bonds within starch during the treatment process.

关键词： computer simulation   thermodynamics   kinetics   acid drainage   hydrocarbons   natural waters   contamination   ore deposits  

摘要： The paper briefly describes some of the problems solved at the Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, to illustrate the possibilities and limitations of the promoted physicochemical computer simulation method. The computer simulation results on the formation of hydrocarbons in the Earth's crust, acid drainage estimates, and other results of the method, obtained by researchers of the Institute of Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry, Russian Academy of Sciences, and colleagues of Tomsk Scientific Polytechnic University, are reported in separate papers.

关键词： hemiparasitic weed   infestation   rainfed rice   rice vampire weed   soil texture   sub‐   Saharan Africa  

摘要： Rainfed lowland rice fields in northern Togo are increasingly infested by the facultative hemiparasitic weed Rhamphicarpa fistulosa that is widely reported throughout sub-Saharan Africa to be one of the most damaging weeds in rice fields. In this geographical area, some studies have shown that soil characteristics may influence the presence and/or the level of infestation of some parasitic weeds, but none have been conducted on R. fistulosa. Based on surveys conducted in northern Togo over two years in 66 lowland rice fields, we characterised the level of infestation of R. fistulosa as well as physico-chemical characteristics of soils. We highlighted that fields with medium-to-high levels of infestation of R. fistulosa (more than 5 plants per m(2)) were mainly characterised by a coarser soil texture, a higher potassium content and a higher pH, while fields without R. fistulosa were characterised by a lower proportion of silt content. In contrast, the level of infestation of R. fistulosa appeared only marginally influenced by soil organic carbon and nitrogen in our study. Considering these results, options to modify the main physico-chemical characteristics of soils that influence the level of infestation of R. fistulosa are likely difficult to implement. In order to continue rice production in these lowland fields, we suggest several measures to better manage R. fistulosa seedbank and development.