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关键词： guar gum   Hibiscus cannabinus   hydrocolloids   kenaf seed   locust bean gum  

摘要： Kenaf seed gum (KSG) is a novel potential hydrocolloid extracted from kenaf seed. The physicochemical and functional characteristics of KSG were compared with guar gum (GG) and locust bean gum (LBG). The Fourier transform infrared (FTIR) analysis of KSG revealed representative peaks of polysaccharides in the regions of 3272, 2923, 1744, 1623, 1448 and 1082 cm(-1). The X-ray diffraction (XRD) patterns displayed an amorphous structure of KSG, similar to other commercial gums. Based on the morphological evaluation, the gums exhibit a smooth surface microstructure. Furthermore, the KSG has comparable functional characteristics as GG and LBG in terms of water solubility, oil-holding capacity, emulsion capacity and foaming capacity. This study provides basic information for exploring KSG as non-conventional seed gum with the potential for further utilisation in the food and non-food industries.

关键词： Cold-pressed oil   fatty acid   functional properties   starch   structure   tigernut tuber  

摘要： Tigernut tuber is a peculiar source of oil because it has high amounts of starch. To collect tigernut oil and obtain high-quality starch from pressed cake, a comprehensive validation of the cold-pressing method was conducted. At 40-60 MPa, from one pressing, 67.18-73.97% of total oil content can be obtained;with three pressings, 77.38-82.34% of total oil can be obtained. Starch yields from solvent extraction of cold-pressed press-cake are significantly higher (P < 0.05) compared with native tigernut flour. For oils from different pressings, the fatty acid and total tocopherol contents had no obvious difference. Structural and functional analysis of the starch showed that cold-press pretreatment had little effect on the particle size and molecular chains of the starch, while the syneresis and storage modulus (G ') of starch gel increased slightly. Overall, cold-pressing is a potential processing method for effectively developing tigernut oil and starch as industrial resources.

关键词： bioactive calcium phosphate coatings   hydroxyapatite   crystallinity   phase composition   detonation spraying  

摘要： Detonation spraying is thought to be a promising approach to producing calcium phosphate bioceramic coatings on various implants owing to the possibility of ensuring conditions that minimize undesirable thermal effects. In this work, this method has been used to produce coatings (up to approximate to 100 mu m in thickness) based on nonstoichiometric hydroxyapatite (HA) with a Ca/P atomic ratio in the range Ca/P approximate to 1.45-1.50 on the surface of titanium substrates. Detailed characterization of the coatings by X-ray diffraction, Raman spectroscopy, and optical and electron microscopy has shown that, under the conditions of this study, the parent HA underwent a number of changes during the spraying process, which led to the formation of tricalcium phosphates (TCPs) (alpha-TCP and beta-TCP) along with HA and amorphous phosphates. As a result, the Ca/P stoichiometric ratio increased (to Ca/P approximate to 1.65-1.67). Osseointegration effectiveness was evaluated in vivo by comparing biological reactions with control specimens (uncoated surgical screws) and coated screws using laboratory animals (Wistar rats). Histological and tomographic examination of ante- and postmortem materials showed that the coatings stimulated chondrogenic osteogenesis in the implant/bone contact region. These effects did not show up until 60 +/- 5 days after implantation.

关键词： Hierarchical porous materials   Micro-meso-macroporous materials   HF etching   F-doped silicon oxycarbide   Supercapacitor  

摘要： Novel hierarchical micro-meso-macroporous fluorine-doped silicon oxycarbide derived materials have been obtained by HF etching of silicon oxycarbides pyrolyzed at different temperatures. The influence of etching time (1 or 24 h) and pyrolysis temperature (from 1100 to 1400 degrees C) on the selective removal of the silica nano-domains present in the silicon oxycarbide and the appearance of oxygen and fluorine functionalities have been determined and evaluated in terms of their electrochemical response. The insertion of fluorine in the silicon oxycarbide matrix (Si-O(F) bonds) and free carbon phase (C-F semi-ionic and C-F covalent bonds) was corroborated. The materials pyrolyzed at 1300-1400 degrees C and etched during 24 h show values of specific capacitance as high as 225-165 Fg(-1) (0.1-30 Ag-1) using a symmetrical configuration and H2SO4 1 M as electrolyte. These materials displayed energy density values of 28-19 Whkg(-1) (0.1-45 kWkg(-1)). The hierarchical microstructure in conjunction with the oxygen and fluorine functionalities are essential in order to explain their good electrochemical response. In particular, those materials present the highest amount of meso (3-10 nm) and larger meso-macropores and the highest content of fluorine in their composition. Then, fluorine-doped silicon oxycarbide derived materials can be potentially used as electrodes for supercapacitors in the field of energy storage applications.

关键词： ionic liquids   fatty acid anion   tetrabutylphosphonium cation   molecular volume   biological activities  

摘要： Ionic liquids (ILs) have remarkable properties and applications in many areas of science. Phosphonium ILs have become important because of their unique chemical and thermal stabilities. The present work is focused on the synthesis, characterisation, physicochemical properties, and microbial toxicity assessment of phosphonium ILs bearing seven different fatty acid anions. The structures of the synthesised ILs were confirmed by 1H and 13C nuclear magnetic resonance (NMR) and FTIR spectroscopy. Physicochemical properties such as density and viscosity of pure ILs were measured at temperatures ranging from 298.15 to 313.15 K. The experimental density decreased, whereas the viscosity increased with an increasing number of carbon atoms in the anion. The derived properties were also found to be anion dependent. The thermal decomposition temperature was investigated by TGA. Subsequently, the toxicity profile of the ILs was determined for selected Gram positive and Gram negative bacteria and some species of fungi in terms of minimum inhibitory concentrations (MIC). The results show that the antimicrobial activities of the ILs are strongly related to the structures of the ILs, where an increase in toxicity was observed with increasing alkyl group chain length of the fatty acid anion.

关键词： DBD plasma   Soy protein isolate   Modification   Protein structure  

摘要： The present study was designed and implemented to modify soy protein isolate (SPI) using dielectric barrier discharge (DBD) plasma and investigate the effects of this treatment on the protein's structural and physicochemical properties. For this purpose, SPI powder was treated with DBD plasma for 0, 5, 10, 15 min at 16, 18, 20 kV. Then, solubility, water holding capacity (WHC), emulsifying activity and emulsion stability, foaming capacity and foam stability, total and reactive sulfhydryl, free carbonyl, FTIR, electrophoretic patterns, as well as protein structures were evaluated. Results indicated that emulsifying properties, solubility, WHC, and foaming activity of SPI were enhanced, and the highest values were obtained after plasma treatment at 18 kV for 15 min. Free and reactive sulfhydryl and free carbonyl contents increased under prolonged exposure to DBD plasma at the applied voltage of 18 kV (p < 0.05). FTIR and circular dichroism (CD) results indicated partial denaturation and unfolding of the alpha-helix structure of SPI followed by the formation of protein aggregates resulting from 15 min plasma exposure;microscopic images also confirmed these results. The above changes indicate successful modification of the physicochemical and functional properties of SPI treated with DBD plasma.

关键词： Calcitonin gene-related peptide   PK/PD   Preformulation   Human effective dose   Migraine   Allometry   Bioanalytical   LC/MS   Pharmacokinetics   Pain   CGRP   Peptide  

摘要： The neuropeptide calcitonin gene-related peptide (CGRP) is known to play a central role in the underlying pathophysiology of migraine. In comparison to the effective triptan class of antimigraine treatments, the CGRP antagonists possess a comparable efficacy but a superior cardiovascular safety profile in patients. This paper describes the development of selective and potent peptidic CGRP antagonist, FE 205030, that has a fast onset of action and an optimal half-life (subcutaneous T-max similar to 60 min, and t(1/2) similar to 4.4 h in 80 kg pigs, respectively), which is key to prevention of the progression of debilitating migraine symptoms. The in vivo efficacy of this agent has been established a translational pharmacodynamic model (inhibition of capsaicin-induced increase in skin blood flow) in cynomolgus monkeys and shows maximal inhibitory activity at circulating concentrations of 30-100 nM. Antagonist activity of FE 205030 was characterized on CGRP-induced vasodilation in isolated human mesenteric resistance arteries in an ex vivo isometric myograph study, and FE 205030 effectively blocked CGRP-induced vasodilation with a pA(2) of 9.3 +/- 0.1, mean +/- standard error. Multispecies allometric scaling and modeling of subcutaneous (SC) effective concentrations indicates that a dose of 10 -30 mg/day is sufficient to achieve a drug exposure/target coverage of 8h, which is useful to prevent migraine recurrence in patients. The molecule also possesses appropriate physicochemical properties that allows for a convenient dosing form factor of 1 ml injection volume with a sufficient solubility and acceptable short-term stability, optimal for treatment of acute migraine episodes in patients. Hence, FE 205030 may provide an important fast-acting injectable option for patients suffering from frequent acute migraine episodes, complementary to preventative monoclonal antibodies and oral small molecule CGRP-R antagonist therapies. (C) 2021 American Pharmacists Association. Pub

关键词： Milling (machining)  

摘要： An investigation of the changes in the properties of starch due to mechanical and thermal effects was taken. The milling temperature and time were strictly controlled, and the particle size, relative crystallinity, damaged starch content, pasting characteristics, and thermal properties of the ground sample from different feed sizes were determined. The results showed that the feed particle size had a significant influence on the particle size distribution, peak viscosity, and final viscosity of the milled product at the initial milling stage. Minimum feed particle size (3.75 similar to 623 mu m) flour has the largest peak viscosity (2,881.5 +/- 58.7 cP & 2,895.0 +/- 38.2 cP) after milling 15 min. The sieving results showed that better breakage effect for coarser particle size after same milling time, particularly under normal temperature. The data of relative crystallinity indicating that keeping a lower temperature range (<25 degrees C) during the milling process may be beneficial to the protection of the starch crystallization. In addition, the difference of thermal properties of the milled products may be caused by the different degrees of starch exposure in endosperm granules and the change of surface protein properties during milling. Novelty impact statement The feed particle size has a significant effect on the peak and final viscosities of the short-time ball milling flour. Cryo-milling can protect the relative crystallinity of wheat granules. The degree of starch granule exposure affects the impact of mechanical force during milling.

关键词： Materials Science   general   Characterization and Evaluation of Materials   Polymer Sciences   Solid Mechanics   Crystallography and Scattering Methods   Classical Mechanics  

摘要： Star-shaped glycopolymers due to the attractive combination of the physicochemical, morphological, self-assembly properties along with biological activity have gained increased attention as innovative agents in novel cancer therapies. Unfortunately, the production of these highly desirable biomaterials remains a challenge in modern macromolecular chemistry. The main reason for that is the low polymerizability of ionic glycomonomers originated from their steric congestion and the occurrence of ionic interactions that generally negatively influence the polymerization progress and hinder controllable reaction pathway. In this work, the new ionic sugar monomer was (co)polymerized for the first time via Activator Generated by Electron Transfer Atom Transfer Radical Polymerization (AGET ATRP) using a three-arm resveratrol-based core to obtain star-like (co)polymers. The obtained products were examined in terms of their physicochemical properties and morphology. Aside from the synthesis of these new glycopolymers, also a thorough description of their thermal properties, ability to self-assembly, the formation of stable superstructures was studied in detail. It was found that examined (co)polymers did not show any heterogeneities and phase separation, while their variation of glass transition temperature (T-g) was strictly related to the change in the number of glycomonomer. Also, the stability and shapes of formed superstructures strictly depend on their composition and topology. Finally, we have shown that synthesized carbohydrate-based polymers revealed high antiproliferative activity against several cancer cell lines (i.e., breast, colon, glioma, and lung cancer). The cytotoxic activity was particularly observed for star-shaped polymers that were systematically enhanced with the growing concentration of amine moieties and molecular weight. The results presented herein suggest that synthesized star-shaped glyco(co)polymers are promising as drug or gene carriers in antica

关键词： Solubility  

摘要： Cassava starch is a raw material and supporting ingredient of the food industry in Indonesia. However, its direct use as the main ingredient in different bakery products remains limited due to its non-expansion ability during baking. The purpose of this study was to examine the effect of chemical modification, drying technique, and drying temperature on the expansion and physicochemical attributes of cassava starch. This study used a combination of techniques, including lactic acid hydrolysis, esterification, and ethanol addition. Subsequently, the obtained product was filtered and dried using a rotary ultraviolet (UV) dryer or an oven (at 40, 45, 55, 65, or 73 degrees C) according to a variable design. Baking expansion, swelling power, and solubility were determined. The combination of lactic acid hydrolysis and UV drying yielded the best result: swelling power (16.4 g/g), solubility (20.4%), and baking expansion (4.2 g/ml). Practical applications Cassava starch is an important ingredient used in baking. Hydrolysis of this starch by UV breaks down its granules, enhancing its expansion properties involved in baking. The modification of cassava starch through hydrolysis, esterification, and ethanol addition had positive effects on starch's physicochemical properties, including swelling, solubility, and baking expansion. Acid hydrolysis-assisted UV irradiation of starch causes the breakdown of the amylopectin chain, thereby forming an amorphous structure. This study presents the modified cassava starch as an alternative raw material in the bakery industry or other food industries. Modified cassava starch has good baking expansion properties, and it preserves the nutrients;these properties enable it to compete with the commonly used materials.