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关键词： Alginate   IFPG   gel beads   Jujube extract   novel functional beverage   pea protein concentrated   whey protein isolated  

摘要： Functional beverage with suspended gel beads made with Jujube extract (as phenolic compounds source), whey protein isolated and chickpea protein concentrated was investigated in this study. There were three types of beads including sodium alginate/insoluble fraction of Persian gum (IFPG), sodium alginate/IFPG/whey protein isolated and sodium alginate/IFPG/pea protein concentrated. The evaluation included pH, acidity, Brix, turbidity, viscosity and sensory properties. The acidity and pH of beverages had a reverse relation as the increase in pH can be due to partial release of the extract. The outcomes showed that the highest viscosity was related to beverages containing chickpea and alginate/IFPG beads. There was a vice versa relation between the spindle round and viscosity. Moreover, the most turbidity was shown in alginate/IFPG/PPC beads' beverage on 14(th) day (232 NTU). Finally, the resulting beverages also showed good sensory properties.

关键词： aged bean starch   amylase   carioca bean cultivars   resistant starch  

摘要： The objective of this study is to characterize Carioca bean starch extract from selected cultivars and harvests in different crop years. The starch is analyzed for amylose content, granule morphology, thermal transition (gelatinization and dissociation of retrograded starch), pasting properties, and in vitro digestibility. Carioca bean starch presents high levels of amylose, ranging from 40.06% to 42.60%. The thermal transition study demonstrates high gelatinization temperatures, from 70.8 to 76.6 degrees C and intense retrogradation. In vitro digestibility of the granular starch evidenced a high content of resistant starch. It is demonstrated for the first time that different cultivars from Brazilian Carioca beans as well as cultivation in distinct crop years are associated with slight differences in the physicochemical characteristics of their starches.

关键词： Colloidal system   Interfacial tension   Plant protein   Non-dairy emulsifier  

摘要： Replacement of dairy proteins by plant proteins is a current trend to produce stable colloidal systems critical to the food and beverage industry. In this study, we compared commercial samples of lentil protein concentrate (LPC) and whey protein concentrate (WPC) to stabilize ultrasound-produced sunflower oil-in-water emulsions. The effects of high-intensity ultrasound (HIUS) (0, 300, 600, 900, and 1200 W) on the LPC-stabilized emulsion properties were evaluated and compared to the emulsion stabilized by WPC, with the aim to assess the challenges and drawbacks of using LPC. Steric stabilization mechanism predominated over electrostatic mechanism. The interfacial tension results showed the ability of LPC to adsorb into the oil-water interface. HIUS processing reduced surface charge density of protein-adsorbed oil droplets, decreasing its contribution to kinetic stabilization. The mean droplet diameter of fresh emulsions showed a significant reduction from 5.44 mu m at 0 W nominal power to 2.07 mu m at 600 W. However, HIUS process intensification by increasing nominal power up to 1200 W increased mean droplet diameter due to starch and dietary fiber aggregation. Although LPC and WPC had distinctive technological properties due to their composition, our results demonstrated that LPC is a promising plant protein to stabilize colloidal systems.

关键词： inorganic nanoparticles   nanomaterials   nanomedicine   physicochemical properties  

摘要： The current review is a guideline for a physicist/chemist/biologist/physician in the introduction of metallic nanocluster (NC) applications and selection of a suitable one from a medical perspective. Metallic nanoclusters have gained attention during recent years owing to their advantages of superior optical characteristics, long lifetime, and biocompatibility for nanomedicine applications, including biolabeling, biosensing, catalysis, bioimaging, drug/gene delivery, and therapeutic agent in comparison to the semiconductor quantum dot analogs. Here their basic physicochemical properties are being introduced, and they are linked to biomedical opportunities. Introducing the needed concepts of noble metal-based nanomaterials is being tried here, along with giving a correct comprehension of the reason for its use in a particular part of biomedical over the last 20 years. Moreover, in each part, a perspective is presented that can guide a researcher on how they can develop or modify new scaffolds for biomedical engineering.

关键词： Ketones  

摘要： This study aimed to investigate the effect of using European cranberrybush (EC;Viburnum opulus L.) juice at three different concentrations (4%, 8%, 12%) on the quality attributes and shelf life (28 days, 4 degrees C) of the yogurts. The addition of EC juice to yogurts promoted a significant increase in all bioactive components of the yogurts. Thirty-seven volatiles were identified as acids, aldehydes, ketones, terpenes, esters, and alcohols. According to texture results, yogurts acted less firmly and consistently based on rising in EC juice concentration. In addition, the scanning electron microscopy results showed that with the addition of EC juice yogurt has a less compact network structure and bigger pores. The principal component analysis revealed that yogurts were distributed at least three quadrants of the score plot at each storage day and also in the preference map the samples were located in different percentages. Novelty impact statement This was the first study proving that European cranberrybush (V. opulus L.) is a promising alternative for increasing the bioactive properties of yogurt. The addition of European cranberrybush juice in yogurt also changed the volatile compound profile of the yogurt, in this regard thirty-seven volatiles were identified with ketones and acids predominating. The European cranberrybush juice addition to the yogurt led to different sensory characteristics, the control yogurt and EJ4 sample were located in the preference map where 80%-100% of the consumers would be satisfied.

关键词： antibacterial   chitosan   layer-by-layer technique   pectin   silver nanocomposites  

摘要： Implant-related infection is one of the serious problems in regenerative medicine. Promising approach to overcome the problems caused by bacterial growth on the medical implants is their modification by bioactive coatings. A versatile technique for designing multilayer films with tailored characteristics at the nanometer scale is layer-by-layer assembly. In this study, multilayer films based on biopolymers (pectin and chitosan) and their nanocomposites with silver nanoparticles have been prepared and evaluated. The buildup of multilayers was monitored using the quartz crystal microbalance with dissipation technique. The morphology of the obtained films was investigated by atomic force microscopy. We have demonstrated that pectin-Ag-containing films were characterized by the linear growth and smooth defect-free surface. When pectin-Ag was substituted for the pectin in the multilayer systems, the properties of the formed coatings were significantly changed: the film rigidity and surface roughness increased, as well as the film growth acquired the parabolic character. All prepared multilayer films have shown antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The significant decrease in the number of the adhered E. coli on the multilayer surface has been determined;moreover, many of the cells were misshapen with cytoplasm leaking. The prepared multilayer films showed a mild activity against S. aureus predominantly due to the antiadhesive effect. Our results indicate that antibacterial activity of biopolymer multilayers is determined by the film composition and physicochemical characteristics and can be associated with their antiadhesive and bactericidal behaviors.

关键词： Sensory analysis  

摘要： The current study examined the quality of twenty wheat varieties for bread making using physicochemical, rheological, and sensory analysis. The effects of various physicochemical parameters, hectoliter ratio (69.1%-76.1%), thousand kilo weight (34.4%-48.2%), and falling number (233-1,160s), showed significant variations among tested varieties. The flour of wheat varieties showed an increasing trend in wet gluten (15.4%-38.3%), dry gluten (7.1%-12.4%), sedimentation (17.66-32.66 mL), moisture (13.3%-16.5%), ash (0.73%-0.90%), protein (11.1%-15.8%), and fat (1%-2.36%). Water absorption (54.1%-63.2%), dough stability (1.3-16.1 min), and dough development time (1.1-12.9 min) were found to be significant rheological parameters for bread quality. Out of twenty;nine best-tested varieties were chosen for bread making and assessed by hedonic scale score including volume (5.72-8.94), crust color (5.86-8.94), crumb color (6.1-8.6), aroma (7.5-8.5), taste (6.92-8.14), and texture (5.88-8.92) respectively. Moreover, principal component analysis having eigenvalues;extracted from the original data, PC1 to PC3 accounting for 75.35% of the variability has also been reported. Novelty impact statement The study concludes that physicochemical, rheological, and other technological attributes of Pakistani wheat varieties are substantially best for bakers in selecting suitable varieties for their intended uses.

关键词： Essential oils  

摘要： The purpose of this study was to prepare an active, nontoxic, and biodegradable film using gelatin and chitosan including rosemary ethanol extract (EE) and essential oil (EO) to improve its physicochemical and antibacterial properties. Films with the highest mechanical properties were acquired using a polymer composition of 4 g gelatin, 3.75 g glycerol, and 1 g chitosan. This composition provided the highest elongation at break (50.10%) and tensile strength (20.61 MPa). The chemical composition of enriched films with rosemary EO was rich in 1,8-cineole, camphor, camphene, and alpha-pinene. The enriched films with rosemary EE were mainly characterized by the predominance of rosmarinic acid and carnosic acid. Mechanical results showed that the incorporation of rosemary EE and EO caused a significant increase in tensile strength, whereas a significant decrease was observed in elongation at break. With the increase of EE and EO concentrations, the water vapor permeability of films decreased while water resistance increased. Moreover, water contact angle analysis showed that the incorporation of rosemary EE and EO made this enriched film more hydrophobic. Fourier transform-infrared (FT-IR) spectroscopy confirmed the formation of intermolecular hydrogen bonds between component functional groups, enhancing the thermal stability and mechanical properties of the enriched films with rosemary EE and EO. Optical results showed that the incorporation of rosemary EE and EO provoked variations in color, light transmission, and transparency of films. The changes of the surface of these films were confirmed by film microstructure analyses with scanning electron microscope (SEM). The antibacterial activity of enriched films with EO and EE was determined against Escherichia coli, Pseudomonas aeruginosa, Campylobacter jejuni, and Salmonella enterica. In fact, the enriched films with EO and EE showed potential coatings for controlling the most common food-borne bacterial growth during t

关键词： Biological properties   endodontic sealer   EndoSequence BC sealer   HiFlow   physical prop-erties   warm vertical compaction  

摘要： Introduction: Understanding the physicochemical and biological properties of endodontic sealers is important for endodontic treatment planning. This study evaluated the properties of EndoSequence BC Sealer HiFlow (BCH;Brasseler USA, Savannah, GA), EndoSequence BC Sealer (BC, Brasseler USA), and AH Plus (AHP;Dentsply DeTrey, Konstanz, Germany). The effect of temperature on the setting time and flow of these sealers was also evaluated. Methods: The setting time, flow, radiopacity, pH, solubility, and calcium release were investigated following ISO guidelines. The morphology and chemical composition of the sealers were evaluated by scanning electron microscopy and energy-dispersive spectros-copy. The antibacterial activity of sealers was tested against 2 strains of Enterococcus fae-calis. Sealer cytotoxicity and the effects on messenger RNA expression of proinflammatory and mineralization genes were also investigated. Data analysis was performed using analysis of variance, Tukey, Kruskal-Wallis, and Dunn multiple comparison tests. P < .05 was considered statistically significant. Results: The setting time and flow rate of all sealers were affected by heat (P < .05). The setting times and solubility of BCH and BC were significantly higher than AHP (P < .0001). The radiopacity of AHP was higher than BCH and BC (P < .0001). All sealers were alkaline and had antibacterial effects. Cell viability was higher for BCH and BC than AHP (P < .0001). No significant differences in messenger RNA expression of proinflammatory and mineralization genes were observed. Conclusions: Overall, BCH and BC had similar physicochemical and biological properties. The observed high solubility of BCH and BC as well as the high cytotoxicity of AHP might negatively impact the clinical performance of these materials. The application of heat affected the setting time and flow of all sealers. (J Endod 2022;48:123-131.) SIGNIFICANCE BC Sealer HiFlow and BC Sealer had similar properties, and their biolog

关键词： Tropical peatland   Peat swamp forest   Peatland degradation   Aboveground carbon stocks   Peat soil  

摘要： Peatlands are unique wetland ecosystems that provide various ecosystem services such as carbon storage and biogeochemical cycling, however being threatened by anthropogenic activities. The present study was conducted to explore the impact of land use conversion on carbon stocks and peat properties in a tropical peatland in the Leyte Sab-a Basin Peatland (LSBP) in Northeastern Leyte, Philippines. The carbon stocks (aboveground and belowground) and physico-chemical properties of peat soil were compared among peat swamp forest, grassland and peatland with cultivation. Land use conversion resulted in the significant reduction of the total aboveground carbon stock. The peat swamp forest had the highest carbon stocks (38.56 +/- 4.58 Mg ha(-1)), and when converted to grassland and peatland with cultivation, it has resulted to carbon loss of as much as 86.59 and 90.45%, respectively. The belowground root carbon stock was highest in the peat swamp forest (5.05 +/- 0.64 Mg ha(-1)), also while highest peat carbon stock (1 m depth) was observed in the cultivation areas (45.28 +/- 2.25 - 61.27 +/- 3.07 Mg ha(-1)). However, peat swamp forests with very deep peat deposits potentially store a significant amount of carbon than in peatland with cultivation that was characterized by shallower compressed peats. In addition, land use conversion altered the physico-chemical properties of peat such as water content, organic matter, and porosity, and bulk density which all indicated peatland degradation. Finally, the overall result of this study highlights the importance to develop and implement management and conservation plans for LSBP.