Switchable Pickering Emulsions Stabilized by Awakened TiO2 Nanoparticle Emulsifiers Using UV/Dark Actuation.

PubMed

Zhang, Qing; Bai, Rui-Xue; Guo, Ting; Meng, Tao

2015-08-26

In this work, switchable Pickering emulsions that utilize UV/dark manipulation employ a type of smart TiO2 nanoparticle as emulsifiers. The emulsifiers can be awakened when needed via UV-induced degradation of grafted silanes on TiO2 nanoparticles. By tuning the surface wettability of TiO2 nanoparticles in situ via UV/dark actuation, emulsions stabilized by the nanoparticles can be reversibly switched between the water-in-oil (W/O) type and oil-in-water (O/W) type for several cycles. Due to the convertible wettability, the smart nanoparticle emulsifiers can be settled in either the oil phase or the water phase as desired during phase separation, making it convenient for recycling. The present work provides a facile and noninvasive method to freely manipulate the formation, breakage, and switching of the emulsion; this method has promising potential as a powerful technique for use in energy-efficient and environmentally friendly industries.

Waste oxide recycling during oxygen steelmaking

NASA Astrophysics Data System (ADS)

Molloseau, Catherine Lynn

The US steel industry generates over three million tons of waste oxides which contain significant amounts of metallic iron and iron oxide. Stringent restrictions imposed on all by-products as well as limited landfill space make disposal of these materials expensive. Currently, companies such as Ispat Inland Steel and National Steel recover the iron units from these waste oxides by recycling them in the form of briquettes into the blast furnace and the Basic Oxygen Furnace (BOF). However, when using the waste oxide briquettes (WOBs) in the BOF, high degrees of slopping have been experienced. Slopping is also a general problem even when WOBs are not used. The goal of this research was to determine the mechanisms influencing the slopping behavior of the slag during oxygen steelmaking with and without WOB additions. In particular, the rate of reduction of FeO in the slag by carbon from iron droplets was studied using the slag and metal compositions representative of the first 50% of the blow (slopping was reported at as early as 30% into the blow). The effect of temperature on the rate of reduction of FeO by carbon in the metal was also studied. From this study, it was found that the behavior of the metal droplets while they reacted with FeO in the slag changed significantly with FeO content. Below 10wt%FeO, the droplet remained intact while reacting with the slag, however, above this FeO concentration, the droplet was observed by x-ray fluoroscopy to become emulsified within the slag. The large increase in surface area of the metal droplet due to emulsification caused the rate of reaction to be one to two orders of magnitude faster than for droplets that did not become emulsified. It was suggested that when the droplet is emulsified, the surface area and reaction kinetics are greatly increased, and the rate becomes controlled by mass transfer of FeO as Fe2+ and O2- ions in the slag to the emulsified droplet. It was also found that a critical temperature exists for a given FeO content at which point the rate of decarburization or CO evolution increases dramatically. Finally, additions of Fe2O 3 to the slag and sulfur to the metal caused relatively significant changes to the rate of reaction possibly by affecting the emulsification behavior of the droplet. The results from this study as well as those from a study which characterized the foaming properties of BOF slags were applied to the oxygen steelmaking process and slopping behavior during the early stages of the blow. From this, new strategies which reduce the possibility of slopping were developed. These included altering the timing of the WOB additions, using fluxed WOBs, and/or altering the blowing practice.

Synthesis and characterization of oleic acid surface modified magnetic iron oxide nanoparticles by using biocompatible w/o microemulsion for heavy metal removal

NASA Astrophysics Data System (ADS)

Rose, Laili Che; Suhaimi, Hamdan; Mamat, Mazidah; Lik, Thang Zhe

2017-09-01

Oleic acid modified magnetic iron oxide nanoparticles (OA-MIONs) was prepared for removal of Cu2+ ion from aqueous solution. OA-MIONs was prepared by W/O microemulsion template which composed of mixed non-ionic surfactants and 1-hexanol as emulsifier. The effect of weight ratio of the constituent of microemulsion template on the physical and chemical properties of OA-MIONs was studied by characterization using Fourier transform infrared (FT-IR), scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) analysis. FT-IR spectra showed that all templates shared similar chemical structure with slight difference in the peak intensity. Scanning electron micrograph illustrated that the OA-MIONs synthesized via template with the lowest weight ratio of emulsifier to heptane had a more regular spherical shape and was well-distributed. XRD had confirmed that the identity of synthesized OA-MIONs was Fe3O4. Based on the characterization result, the template with lowest weight ratio of emulsifier to heptane was chosen for the heavy metal adsorption study. The adsorption capacity OA-MIONs as a function of pH, contact time and adsorbent dosage were studied. The adsorption process reached equilibrium for 90 minutes and successfully adsorbed 43% of Cu2+ ion from aqueous solution. The adsorption behavior was well described by Langmuir isotherm. The maximum adsorption capacity was determined and found to be 555.56 mg/g. The value of Langmuir equilibrium parameter, RL was found between 0 and 1, suggested that a favorable monolayer adsorption process had taken out.

Effect of nonionic compound emulsifiers Tween80 and Span80 on the properties of microencapsulated phase change materials.

PubMed

Zhan, Shiping; Zhou, Zhiyi; Wang, Weijing; Zhao, Qicheng; Hou, Weimin

2014-01-01

In this article, the nonionic compound emulsifiers Tween80 and Span80 were used to prepare microcapsules containing phase change materials (microPCMs) with melamine-formaldehyde (MF) shells by in situ polymerization method. The effects of compound emulsifiers Tween80 and Span80 on the structure, morphologies and properties of microPCMs containing paraffin were studied. SEM morphological investigation suggests that a complex of Tween80 and Span80 as emulsifiers are optimal for the fabrication of microPCMs in this study compared to Tween60 or OP-10. The diameter distributions of microPCMs synthesized with different amounts of compound emulsifiers are uniform, whereas compound emulsifiers' amount affect the mean diameter of microPCMs decreasing from 5.34 to 3.05 µm. These microPCMs with the core/shell weight ratio 3/1 have smoother surface and a higher core content of 68.7% than other core/shell ratio. Anti-osmosis measurements indicate that microPCMs have good compactness and stable performance compared to those synthesized by one type of emulsifier.

Antioxidant Properties of Astaxanthin in Oil-in-Water Emulsions with Differently-Charged Emulsifiers Under Chlorophyll Photosensitization.

PubMed

Yi, BoRa; Kim, Mi-Ja; Lee, JaeHwan

2018-03-01

The antioxidative or prooxidative properties of astaxanthin at the concentrations of 0, 10, and 100 μM were determined in oil-in-water (O/W) emulsions containing neutral, anionic, and cationic emulsifiers, which was Tween 20, sodium dodecyl sulfate, cetyltrimethylammonium bromide (CTAB), respectively, under chlorophyll photosensitization. The oxidative parameters and headspace volatiles were analyzed in O/W emulsions. In the 24 h period of visible light irradiation, 100 μM of astaxanthin acted as an antioxidant in O/W emulsions containing neutral and anionic emulsifiers. However, astaxanthin in O/W emulsions with a cationic emulsifier was neither an antioxidant nor a prooxidant. The profiles of volatile compounds showed that astaxanthin served as a singlet oxygen quencher in O/W emulsions containing neutral and anionic emulsifiers. However, in O/W emulsion with a cationic emulsifier, astaxanthin was neither a singlet oxygen quencher nor a free radical scavenger because prooxidant properties of CTAB overwhelmed the antioxidant effects of astaxanthin. Therefore, the antioxidant properties of astaxanthin were influenced by the emulsifier charges in O/W emulsions. Astaxanthin is a lipid-soluble pigment and has antioxidant, anticancer, and anti-inflammatory properties and beneficial effects on cardiovascular diseases. Many lipid-based foods are displayed on the shelves in the markets under fluorescent light. The addition of astaxanthin can extend the shelf life of O/W emulsion type foods such as beverage and dressing products under visible light irradiation. Also, oxidative stability in emulsion type foods containing astaxanthin rich natural ingredients can be predicted. © 2018 Institute of Food Technologists®.

Use of Nanoscale Emulsified Zero-valent Iron to Treat a Chlorinated Solvent Source Zone at Site 45, Marine Corp Recruit Depot, Parris Island, South Carolina

EPA Science Inventory

This document summarizes the research activities currently underway at the Solid Waste Management Unit 45 (Site 45), Marine Corps Recruit Depot, Parris Island, South Carolina. A pilot field test was initiated in 2005 at this site to evaluate the effectiveness of nanoscale emulsif...

Competitive displacement of sodium caseinate by low-molecular-weight emulsifiers and the effects on emulsion texture and rheology.

PubMed

Munk, M B; Larsen, F H; van den Berg, F W J; Knudsen, J C; Andersen, M L

2014-07-29

Low-molecular-weight (LMW) emulsifiers are used to promote controlled destabilization in many dairy-type emulsions in order to obtain stable foams in whippable products. The relation between fat globule aggregation induced by three LMW emulsifiers, lactic acid ester of monoglyceride (LACTEM), saturated monoglyceride (GMS), and unsaturated monoglyceride (GMU) and their effect on interfacial protein displacement was investigated. It was found that protein displacement by LMW emulsifiers was not necessary for fat globule aggregation in emulsions, and conversely fat globule aggregation was not necessarily accompanied by protein displacement. The three LMW emulsifiers had very different effects on emulsions. LACTEM induced shear instability of emulsions, which was accompanied by protein displacement. High stability was characteristic for emulsions with GMS where protein was displaced from the interface. Emulsions containing GMU were semisolid, but only low concentrations of protein were detected in the separated serum phase. The effects of LACTEM, GMS, and GMU may be explained by three different mechanisms involving formation of interfacial α-gel, pickering stabilization and increased exposure of bound casein to the water phase. The latter may facilitate partial coalescence. Stabilizing hydrocolloids did not have any effect on the LMW emulsifiers' ability to induce protein displacement.

Treatment of emulsified oils by electrocoagulation: pulsed voltage applications.

PubMed

Genc, Ayten; Bakirci, Busra

2015-01-01

The effect of pulsed voltage application on energy consumption during electrocoagulation was investigated. Three voltage profiles having the same arithmetic average with respect to time were applied to the electrodes. The specific energy consumption for these profiles were evaluated and analyzed together with oil removal efficiencies. The effects of applied voltages, electrode materials, electrode configurations, and pH on oil removal efficiency were determined. Electrocoagulation experiments were performed by using synthetic and real wastewater samples. The pulsed voltages saved energy during the electrocoagulation process. In continuous operation, energy saving was as high as 48%. Aluminum electrodes used for the treatment of emulsified oils resulted in higher oil removal efficiencies in comparison with stainless steel and iron electrodes. When the electrodes gap was less than 1 cm, higher oil removal efficiencies were obtained. The highest oil removal efficiencies were 95% and 35% for the batch and continuous operating modes, respectively.

Fat reduction in comminuted meat products-effects of beef fat, regular and pre-emulsified canola oil.

PubMed

Youssef, M K; Barbut, S

2011-04-01

The effects of fat reduction (25.0%, 17.5%, and 10.0%) and substituting beef fat with canola oil or pre-emulsified canola oil (using soy protein isolate, sodium caseinate or whey protein isolate) on cooking loss, texture and color of comminuted meat products were investigated. Reducing fat from 25 to 10% increased cooking loss and decreased hardness. Canola oil or pre-emulsified treatments showed a positive effect on improving yield and restoring textural parameters. Using sodium caseinate to pre-emulsify the oil resulted in the highest hardness value. Cohesiveness was affected by fat type and level. The color of reduced fat meat batters was darker for all, except the beef fat treatments. Using canola oil or pre-emulsified oil resulted in a significant reduction in redness. The results show that pre-emulsification can offset some of the changes in reduced fat meat products when more water is used to substitute for the fat and that pre-emulsification can also help to produce a more stable meat matrix. © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

Impact of Lipid Components and Emulsifiers on Plant Sterols Bioaccessibility from Milk-Based Fruit Beverages.

PubMed

Alvarez-Sala, Andrea; Garcia-Llatas, Guadalupe; Cilla, Antonio; Barberá, Reyes; Sánchez-Siles, Luis Manuel; Lagarda, María Jesús

2016-07-20

Sterol bioaccessibility (BA) of three plant sterol (PS)-enriched milk-based fruit beverages (MFb) with different fat contents (1.1-2.4%), lipid sources (animal or vegetable), and without or with emulsifiers (whey proteins enriched with milk fat globule membrane (MFGM) or soy lecithin) was evaluated after simulated gastrointestinal digestion. The BA of total PS followed the order 31.4% (MFbM containing milk fat and whey proteins enriched with MFGM) = 28.2% (MFbO containing extra virgin olive oil and soy lecithin) > 8.7% (MFb without fat addition). Total and individual PS content in the bioaccessible fractions followed the order MFbM > MFbO > MFb. Consequently, formulation with MFGM is proposed in beverages of this kind to ensure optimum bioavailability of PS. Our results suggest that the BA of PS is influenced by the type and quantity of fat and the emulsifier type involved.

Application of a long-lasting colloidal substrate with pH and hydrogen sulfide control capabilities to remediate TCE-contaminated groundwater.

PubMed

Sheu, Y T; Chen, S C; Chien, C C; Chen, C C; Kao, C M

2015-03-02

A long-lasting emulsified colloidal substrate (LECS) was developed for continuous carbon and nanoscale zero-valent iron (nZVI) release to remediate trichloroethylene (TCE)-contaminated groundwater under reductive dechlorinating conditions. The developed LECS contained nZVI, vegetable oil, surfactants (Simple Green™ and lecithin), molasses, lactate, and minerals. An emulsification study was performed to evaluate the globule droplet size and stability of LECS. The results show that a stable oil-in-water emulsion with uniformly small droplets (0.7 μm) was produced, which could continuously release the primary substrates. The emulsified solution could serve as the dispensing agent, and nZVI particles (with diameter 100-200 nm) were distributed in the emulsion evenly without aggregation. Microcosm results showed that the LECS caused a rapid increase in the total organic carbon concentration (up to 488 mg/L), and reductive dechlorination of TCE was significantly enhanced. Up to 99% of TCE (with initial concentration of 7.4 mg/L) was removed after 130 days of operation. Acidification was prevented by the production of hydroxide ion by the oxidation of nZVI. The formation of iron sulfide reduced the odor from produced hydrogen sulfide. Microbial analyses reveal that dechlorinating bacteria existed in soils, which might contribute to TCE dechlorination. Copyright © 2014 Elsevier B.V. All rights reserved.

Field demonstration of DNAPL dehalogenation using emulsified zero-valent iron

NASA Technical Reports Server (NTRS)

Quinn, Jacqueline; Geiger, Cherie; Clausen, Chris; Brooks, Kathleen; Coon, Christina; O'Hara, Suzanne; Krug, Thomas; Major, David; Yoon, Woong-Sang; Gavaskar, Arun;

Field Demonstration of DNAPL Dehalogenation Using Emulsified Zero-Valent Iron

NASA Technical Reports Server (NTRS)

Quinn, Jacqueline; Geiger, Cherie; Clausen, Chris; Brooks, Kathleen; Coon, Christina; O'Hara, Suzanne; Krug, Thomas; Major, David; Yoon, Sam; Gavaskar, Arun;

An alkyl polyglucoside-mixed emulsifier as stabilizer of emulsion systems: the influence of colloidal structure on emulsions skin hydration potential.

PubMed

Savic, Snezana; Lukic, Milica; Jaksic, Ivana; Reichl, Stephan; Tamburic, Slobodanka; Müller-Goymann, Christel

2011-06-01

To be considered as a suitable vehicle for drugs/cosmetic actives, an emulsion system should have a number of desirable properties mainly dependent on surfactant used for its stabilization. In the current study, C(12-14) alkyl polyglucoside (APG)-mixed emulsifier of natural origin has been investigated in a series of binary (emulsifier concentration 10-25% (w/w)) and ternary systems with fixed emulsifier content (15% (w/w)) with or without glycerol. To elucidate the systems' colloidal structure the following physicochemical techniques were employed: polarization and transmission electron microscopy, X-ray diffraction (WAXD and SAXD), thermal analysis (DSC and TGA), complex rheological, pH, and conductivity measurements. Additionally, the emulsion vehicles' skin hydration potential was tested in vivo, on human skin under occlusion. In a series of binary systems with fixed emulsifier/water ratios ranging from 10/90 to 25/75 the predominance of a lamellar mesophase was found, changing its character from a liquid crystalline to a gel crystalline type. The same was observed in gel emulsions containing equal amounts of emulsifier and oil (15% (w/w)), but varying in glycerol content (0-25%). Different emulsion samples exhibited different water distribution modes in the structure, reflecting their rheological behavior and also their skin hydration capacity. Copyright © 2011 Elsevier Inc. All rights reserved.

Phosphate Reduction in Emulsified Meat Products: Impact of Phosphate Type and Dosage on Quality Characteristics.

PubMed

Glorieux, Seline; Goemaere, Olivier; Steen, Liselot; Fraeye, Ilse

2017-09-01

Phosphate reduction is of important industrial relevance in the manufacturing of emulsified meat products because it may give rise to a healthier product. The effect of seven different phosphate types was tested on the physicochemical and quality characteristics to select the most promising phosphate type for further cooked sausage manufacturing. Next, phosphate mass fraction was gradually reduced. Tetrasodium di- or pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) increased pH, reduced structural properties, resulted in the highest emulsion stability, lowest cooking loss and had little effect on hardness. Based on the viscoelastic properties, a minimum mass fraction of 0.06% TSPP was sufficient to obtain an acceptable quality product. Rheology proved to be a very useful tool to evaluate the quality of meat products, as it gives insight in the structure of the meat product and especially the functional properties of meat proteins. Based on the obtained results, it can be concluded that the current amount of phosphate added to emulsified meat products can be significantly reduced with minimal loss of product quality.

Phosphate Reduction in Emulsified Meat Products: Impact of Phosphate Type and Dosage on Quality Characteristics

PubMed Central

2017-01-01

Summary Phosphate reduction is of important industrial relevance in the manufacturing of emulsified meat products because it may give rise to a healthier product. The effect of seven different phosphate types was tested on the physicochemical and quality characteristics to select the most promising phosphate type for further cooked sausage manufacturing. Next, phosphate mass fraction was gradually reduced. Tetrasodium di- or pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) increased pH, reduced structural properties, resulted in the highest emulsion stability, lowest cooking loss and had little effect on hardness. Based on the viscoelastic properties, a minimum mass fraction of 0.06% TSPP was sufficient to obtain an acceptable quality product. Rheology proved to be a very useful tool to evaluate the quality of meat products, as it gives insight in the structure of the meat product and especially the functional properties of meat proteins. Based on the obtained results, it can be concluded that the current amount of phosphate added to emulsified meat products can be significantly reduced with minimal loss of product quality. PMID:29089852

Effect of soybean lecithin on iron-catalyzed or chlorophyll-photosensitized oxidation of canola oil emulsion.

PubMed

Choe, Jeesu; Oh, Boyoung; Choe, Eunok

2014-11-01

The effect of soybean lecithin addition on the iron-catalyzed or chlorophyll-photosensitized oxidation of emulsions consisting of purified canola oil and water (1:1, w/w) was studied based on headspace oxygen consumption using gas chromatography and hydroperoxide production using the ferric thiocyanate method. Addition levels of iron sulfate, chlorophyll, and soybean lecithin were 5, 4, and 350 mg/kg, respectively. Phospholipids (PLs) during oxidation of the emulsions were monitored by high performance liquid chromatography. Addition of soybean lecithin to the emulsions significantly reduced and decelerated iron-catalyzed oil oxidation by lowering headspace oxygen consumption and hydroperoxide production. However, soybean lecithin had no significant antioxidant effect on chlorophyll-photosensitized oxidation of the emulsions. PLs in soybean lecithin added to the emulsions were degraded during both oxidation processes, although there was little change in PL composition. Among PLs in soybean lecithin, phosphatidylethanolamine and phosphatidylinositol were degraded the fastest in the iron-catalyzed and the chlorophyll-photosensitized oxidation, respectively. The results suggest that addition of soybean lecithin as an emulsifier can also improve the oxidative stability of oil in an emulsion. © 2014 Institute of Food Technologists®

Influence of non-ionic emulsifier type on the stability of cinnamaldehyde nanoemulsions: A comparison of polysorbate 80 and hydrophobically modified inulin.

PubMed

Sedaghat Doost, Ali; Dewettinck, Koen; Devlieghere, Frank; Van der Meeren, Paul

2018-08-30

Cinnamaldehyde nanoemulsions were formulated to enable its application in an aqueous environment. The pure cinnamaldehyde nanoemulsions, stabilized by polysorbate 80 (at concentrations >0.5%), had both a higher stability and smaller droplet size, whereas the emulsions containing hydrophobically modified inulin (HMI) formed a colloidal dispersion with larger particle size. Incorporation of sunflower oil (SO) allowed postponement of Ostwald ripening for a sufficiently long period of time (at least 60 days). Cryo-SEM and droplet size analyses of the nanoemulsions emulsified by HMI revealed no significant changes during storage. Under these conditions, HMI as an emulsifier exhibited a powerful resistance to high salt contents (up to 2 M) and high thermal processing temperatures (90 °C). The surfactant type and SO content had no marked influence on the antimicrobial activity of the nanoemulsions. This study provides precious information for a commercial formulation of nanoemulsions with durable physical stability under severe stress conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Influence of lipid type on gastrointestinal fate of oil-in-water emulsions: In vitro digestion study.

PubMed

Zhang, Ruojie; Zhang, Zipei; Zhang, Hui; Decker, Eric Andrew; McClements, David Julian

2015-09-01

The potential gastrointestinal fate of oil-in-water emulsions containing lipid phases from different sources was examined: vegetable oils (corn, olive, sunflower, and canola oil); marine oils (fish and krill oil); flavor oils (orange and lemon oil); and, medium chain triglycerides (MCT). The lowest rates and extents of lipid digestion were observed for emulsified flavor oil, followed by emulsified krill oil. There was no appreciable difference between the final amounts of free fatty acids released for emulsified digestible oils. Differences in the digestibility of emulsions prepared using different oils were attributed to differences in their compositions, e.g., fatty acid chain length and unsaturation. The particle size distribution, particle charge, microstructure, and macroscopic appearance of the emulsions during passage through the simulated GIT depended on oil type. The results of this study may facilitate the design of functional foods that control the digestion and absorption of triglycerides, as well as the bioaccessibility of hydrophobic bioactives. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preparation, characterization, and in vitro gastrointestinal digestibility of oil-in-water emulsion-agar gels.

PubMed

Wang, Zheng; Neves, Marcos A; Kobayashi, Isao; Uemura, Kunihiko; Nakajima, Mitsutoshi

2013-01-01

Soybean oil-in-water (O/W) emulsion-agar gel samples were prepared and their digestibility evaluated by using an in vitro gastrointestinal digestion model. Emulsion-agar sols were obtained by mixing the prepared O/W emulsions with a 1.5 wt % agar solution at 60 °C, and their subsequent cooling at 5 °C for 1 h formed emulsion-agar gels. Their gel strength values increased with increasing degree of polymerization of the emulsifiers, and the relative gel strength increased in the case of droplets with an average diameter smaller than 700 nm. Flocculation and coalescence of the released emulsion droplets depended strongly on the emulsifier type; however, the emulsifier type hardly affected the ζ-potential of emulsion droplets released from the emulsion-agar gels during in vitro digestion. The total FFA content released from each emulsion towards the end of the digestion period was nearly twice that released from the emulsion-agar gel, indicating that gelation of the O/W emulsion may have delayed lipid hydrolysis.

Microencapsulation of essential oil for insect repellent in food packaging system.

PubMed

Chung, Seong Kyun; Seo, Ji Yeon; Lim, Jung Hoon; Park, Hyung Hwan; Yea, Myeong Jai; Park, Hyun Jin

2013-05-01

Microcapsules containing thyme oil were prepared by in situ polymerization, using melamine-formaldehyde prepolymer as a wall material and 3 different emulsifiers (pluronic F-127, tween 80, and sodium lauryl sulfate [SLS]). The general characteristics and release behavior of microcapsules, and their repellent effect against insects were investigated. The morphology of microcapsules using SLS was spherical shape with smooth surface. Microcapsules began to degrade at 150 °C. The particle size ranged from 1 to 10 μm and the loading efficiency of thyme oil was clearly affected by the emulsifier type. The highest loading efficiency appeared in microcapsules using SLS, which have good thermal resistance and smooth surface. The release rate of thyme oil from microcapsules was not only dependent on the storage temperature but also emulsifier type and microcapsules showed the sustained release properties for a long time. Diets, which were mixed with encapsulated thyme oil, expressed high insect repellent efficacy over 90% for 4 wk. © 2013 Institute of Food Technologists®

Influence of membrane material on the production of colloidal emulsions by premix membrane emulsification.

PubMed

Gehrmann, Sandra; Bunjes, Heike

2018-05-01

Premix membrane emulsification is a possibility to produce colloidal emulsions as carrier systems for poorly water soluble drugs. During the extrusion of a coarse pre-emulsion through a porous membrane, the emulsion droplets are disrupted into smaller droplets. The influence of the membrane material on the emulsification success was investigated in dependence on the emulsifier. Premixed medium chain triglyceride (MCT) emulsions stabilized with five different emulsifiers were extruded through seven different hydrophilic polymeric membrane materials with pore sizes of 200nm. The resulting emulsions differed strongly in particle size and particle size distribution with a range of median particle sizes between 0.08μm and 11μm. The particle size of the emulsions did not depend mainly on the structure or thickness of the membrane but on the combination of emulsifier and membrane material. Contact angle measurements indicated that the wetting of the membrane with the continuous phase of the emulsion was decisive for achieving emulsions with colloidal particle sizes. The type of dispersed phase was of minor importance as basically the same results were obtained with peanut oil instead of MCT. To prove the assumption that only sufficiently hydrophilic membrane materials led to emulsions with colloidal particle sizes, two membrane materials were hydrophilized by plasma treatment. After hydrophilization, the emulsifying process led to emulsions with smaller particle sizes. The use of an alumina membrane (Anodisc®) improved the process even more. With this type of membrane, emulsions with a median particle size below 250nm and a narrow particle size distribution could be obtained with all investigated emulsifiers. Copyright © 2016 Elsevier B.V. All rights reserved.

Designing excipient emulsions to increase nutraceutical bioavailability: emulsifier type influences curcumin stability and bioaccessibility by altering gastrointestinal fate.

PubMed

Zou, Liqiang; Liu, Wei; Liu, Chengmei; Xiao, Hang; McClements, David Julian

2015-08-01

The influence of emulsifier type on the ability of excipient emulsions to improve the solubility, stability, and bioaccessibility of powdered curcumin was examined. Oil-in-water emulsions prepared using three different emulsifiers (whey protein isolate, caseinate, or Tween 80) were mixed with curcumin powder and then incubated at either 30 °C (to simulate applications of salad dressings) or 100 °C (to simulate applications of cooking sauces). The transfer of curcumin into the excipient emulsions was appreciably higher for excipient emulsions held at 100 °C than those held at 30 °C, and was appreciably higher for surfactant-stabilized emulsions than protein-stabilized emulsions. For example, the amounts of curcumin transferred into emulsions held at 30 and 100 °C were 66 and 280 μg mL(-1) for Tween 80, but only 17 and 208 μg mL(-1) for caseinate. The total curcumin concentration in the digesta and mixed micelle phases collected after excipient emulsions were exposed to a simulated gastrointestinal tract (mouth, stomach, and small intestine) depended on emulsifier type. The total amount of curcumin within the digesta was higher for protein-stabilized emulsions than surfactant-stabilized ones, which was attributed to the ability of the proteins to protect curcumin from chemical degradation. For example, the digesta contained 204 μg mL(-1) curcumin for caseinate emulsions, but only 111 μg mL(-1) for Tween 80 emulsions. This study shows the potential of designing excipient emulsions to increase the oral bioavailability of curcumin for food and pharmaceutical applications.

Evaluation of the Properties Magnesium Phosphate Cement with Emulsified Asphalt

NASA Astrophysics Data System (ADS)

Du, Jia-Chong; Shen, Ruei-Siang; Zhou, Yu-Zhun

2017-10-01

Three type mixtures of magnesium phosphate cement with emulsified asphalt for evaluation their properties. The mixtures of the samples were fabricated and allowed them 2 hours, seven and twenty eight days curing before tested by compressive strength, Marshall stability and indirect tensile strength to probe into their engineering properties. The test results show that all tests have the greatest values at the 28 days curing and too much asphalt emulsion may cause too soft as result of low stability. The compressive strength of Type-III mixture has the greatest value, no matter what curing time is. The Marshall stability test and indirect tensile strength of the Type-III mixture are qualified by the specification required for fast maintenance. The more asphalt emulsion added, the less compressive strength has.

Effect of emulsifier type and concentration, aqueous phase volume and wax ratio on physical, material and mechanical properties of water in oil lipsticks.

PubMed

Beri, A; Norton, J E; Norton, I T

2013-12-01

Water-in-oil emulsions in lipsticks could have the potential to improve moisturizing properties and deliver hydrophilic molecules to the lips. The aims of this work were (i) to investigate the effect of emulsifier type (polymer vs. monomer, and saturated vs. unsaturated chain) and concentration on droplet size and (ii) to investigate the effect of wax ratio (carnauba wax, microcrystalline wax, paraffin wax and performalene) and aqueous phase volume on material properties (Young's modulus, point of fracture, elastic modulus and viscous modulus). Emulsion formation was achieved using a high shear mixer. Results showed that the saturated nature of the emulsifier had very little effect on droplet size, neither did the use of an emulsifier with a larger head group (droplet size ~18-25 μm). Polyglycerol polyricinoleate (PGPR) resulted in emulsions with the smallest droplets (~3-5 μm), as expected from previous studies that show that it produces a thick elastic interface. The results also showed that both Young's modulus and point of fracture increase with increasing percentage of carnauba wax (following a power law dependency of 3), but decrease with increasing percentage of microcrystalline wax, suggesting that the carnauba wax is included in the overall wax network formed by the saturated components, whereas the microcrystalline wax forms irregular crystals that disrupt the overall wax crystal network. Young's modulus, elastic modulus and viscous modulus all decrease with increasing aqueous phase volume in the emulsions, although the slope of the decrease in elastic and viscous moduli is dependent on the addition of solid wax, as a result of strengthening the network. This work suggests the potential use for emulsions in lipstick applications, particularly when PGPR is used as an emulsifier, and with the addition of solid wax, as it increases network strength. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Safe, in situ methodologies for the destruction of triacetone triperoxide and other explosive peroxides

NASA Technical Reports Server (NTRS)

Geiger, Cherie L. (Inventor); Sigman, Michael (Inventor); Clausen, III, Christian (Inventor); Fidler, Rebecca (Inventor)

2011-01-01

Triacetone triperoxide (TATP) and other explosives of the peroxide family are safely degraded in situ. Nano and micron size metal particles in an elemental state include pure iron and magnesium or iron and magnesium particles that are mechanically alloyed with palladium and nickel. The metal particles are used in both the elemental state and in emulsions that are made from water, a hydrophobic solvent, such as corn oil, and a food-grade nonionic surfactant. The neat metals and emulsified zero valent metals (EZVM) safely degrade TATP with the major degradation product being acetone. The EZVM system absorbs and dissolves the TATP into the emulsion droplets where TATP degradation occurs. EZVM systems are ideal for degrading dry TATP crystals that may be present on a carpet or door entrance. Both the neat metal system and the emulsion system (EZVM) degrade TATP in an aqueous slurry.

Evaluating Trichloroethylene Degradation Using Differing Nano- and Micro-Scale Iron Particles

NASA Technical Reports Server (NTRS)

Berger, Cristina M.; Geiger, Cherie L.; Clausen, Christian A.; Billow, Alexa M.; Quinn, Jacqueline W.; Brooks, Kathleen B.

2006-01-01

Trichioroethylene, or TCE, is a central nervous system depressant and possible carcinogen, as well as a persistent groundwater pollutant. TCE exists in the aquifer either as free product in the form of a dense non-aqueous phase liquid (DNAPL) or as a dissolved-phase constituent. It is only slightly soluble in water, so dissolution of the contaminant is a long-term process and in-situ remediation is difficult. To remedy this, NASA and the University of Central Florida developed Emulsified Zero-Valent Iron, or EZVI. The emulsion droplet contains ZVI particles and water encapsulated by an oil/surfactant membrane, and effectively penetrates to degrade DNAPL-phase TCE. To maximize the efficiency of this process, several commercially available ZVIs of radically different particle sizes and morphologies both in emulsion and as neat (unemulsified) metal were evaluated for relative effectiveness at TCE degradation.

Solutions Remediate Contaminated Groundwater

NASA Technical Reports Server (NTRS)

2010-01-01

During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.

Waffle Production: Influence of Baking Plate Material on Sticking of Waffles.

PubMed

Huber, Regina; Kalss, Georg; Schoenlechner, Regine

2017-01-01

Background of this study was to understand the factors that contribute to sticking of fresh egg waffles on baking plates. The aim of this study was to investigate the sticking (adhesion) behavior of waffles on 4 different baking plate materials (ductile iron, grey iron, low alloyed steel, and steel with titanium nitrite coating) at different baking parameters (temperature and time) and application of 3 different release agents (different fat compositions). Baking plates from ductile and grey iron showed lower release properties of waffles than the 2 steel baking plates. Baking parameters had to be high enough to allow rapid product crust formation but prevent burning, which again increases sticking behavior. Release agents based on short-chain fatty acids with higher degree of saturation provided better release behavior of waffles than those based on long-chain fatty acids or on emulsifier-acid combinations. Baking plates with increased hardness, good heat storage capacity, and smooth surface seemed to be best suitable. Further research on appropriate coating material might be promising for future. © 2016 Institute of Food Technologists®.

Natural emulsifiers - Biosurfactants, phospholipids, biopolymers, and colloidal particles: Molecular and physicochemical basis of functional performance.

PubMed

McClements, David Julian; Gumus, Cansu Ekin

2016-08-01

There is increasing consumer pressure for commercial products that are more natural, sustainable, and environmentally friendly, including foods, cosmetics, detergents, and personal care products. Industry has responded by trying to identify natural alternatives to synthetic functional ingredients within these products. The focus of this review article is on the replacement of synthetic surfactants with natural emulsifiers, such as amphiphilic proteins, polysaccharides, biosurfactants, phospholipids, and bioparticles. In particular, the physicochemical basis of emulsion formation and stabilization by natural emulsifiers is discussed, and the benefits and limitations of different natural emulsifiers are compared. Surface-active polysaccharides typically have to be used at relatively high levels to produce small droplets, but the droplets formed are highly resistant to environmental changes. Conversely, surface-active proteins are typically utilized at low levels, but the droplets formed are highly sensitive to changes in pH, ionic strength, and temperature. Certain phospholipids are capable of producing small oil droplets during homogenization, but again the droplets formed are highly sensitive to changes in environmental conditions. Biosurfactants (saponins) can be utilized at low levels to form fine oil droplets that remain stable over a range of environmental conditions. Some nature-derived nanoparticles (e.g., cellulose, chitosan, and starch) are effective at stabilizing emulsions containing relatively large oil droplets. Future research is encouraged to identify, isolate, purify, and characterize new types of natural emulsifier, and to test their efficacy in food, cosmetic, detergent, personal care, and other products. Copyright © 2016 Elsevier B.V. All rights reserved.

Whey protein/polysaccharide-stabilized emulsions: Effect of polymer type and pH on release and topical delivery of salicylic acid.

PubMed

Combrinck, Johann; Otto, Anja; du Plessis, Jeanetta

2014-06-01

Emulsions are widely used as topical formulations in the pharmaceutical and cosmetic industries. They are thermodynamically unstable and require emulsifiers for stabilization. Studies have indicated that emulsifiers could affect topical delivery of actives, and this study was therefore designed to investigate the effects of different polymers, applied as emulsifiers, as well as the effects of pH on the release and topical delivery of the active. O/w emulsions were prepared by the layer-by-layer technique, with whey protein forming the first layer around the oil droplets, while either chitosan or carrageenan was subsequently adsorbed to the protein at the interface. Additionally, the emulsions were prepared at three different pH values to introduce different charges to the polymers. The active ingredient, salicylic acid, was incorporated into the oil phase of the emulsions. Physical characterization of the resulting formulations, i.e., droplet size, zeta potential, stability, and turbidity in the water phase, was performed. Release studies were conducted, after which skin absorption studies were performed on the five most stable emulsions, by using Franz type diffusion cells and utilizing human, abdominal skin membranes. It was found that an increase in emulsion droplet charge could negatively affect the release of salicylic acid from these formulations. Contrary, positively charged emulsion droplets were found to enhance dermal and transdermal delivery of salicylic acid from emulsions. It was hypothesized that electrostatic complex formation between the emulsifier and salicylic acid could affect its release, whereas electrostatic interaction between the emulsion droplets and skin could influence dermal/transdermal delivery of the active.

Influence of surfactants on gas-hydrate formation' kinetics in water-oil emulsion

NASA Astrophysics Data System (ADS)

Zemenkov, Yu D.; Shirshova, A. V.; Arinstein, E. A.; Shuvaev, A. N.

2018-05-01

The kinetics of gas hydrate formation of propane in a water-oil emulsion is experimentally studied when three types of surfactants (SAA (surface acting agent)) - anionic type emulsifiers - are added to the aqueous phase. It is shown that all three types of surfactants decelerate the growth of the gas-hydrate in the emulsion and can be considered as anti-agglutinating and kinetic low-dose inhibitors. The most effective inhibitor of hydrate formation in water-oil emulsion of SV-102 surfactant was revealed. For comparison, experimental studies of gas-hydrate formation under the same conditions for bulk water have been carried out. It is shown that in bulk water, all the surfactants investigated act as promoters (accelerators) of hydrate formation. A qualitative explanation of the action mechanisms of emulsifiers in the process of gas-hydrate formation in water-oil emulsion is given.

Effect of binary organic solvents together with emulsifier on particle size and in vitro behavior of paclitaxel-encapsulated polymeric lipid nanoparticles.

PubMed

Qin, Shuzhi; Sun, Xiangshi; Li, Feng; Yu, Kongtong; Zhou, Yulin; Liu, Na; Zhao, Chengguo; Teng, Lesheng; Li, Youxin

2017-12-21

Biodegradable nanoparticles with diameters between 100 nm and 500 nm are of great interest in the contexts of targeted delivery. The present work provides a review concerning the effect of binary organic solvents together with emulsifier on particle size as well as the influence of particle size on the in vitro drug release and uptake behavior. The polymeric lipid nanoparticles (PLNs) with different particle sizes were prepared by using binary solvent dispersion method. Various formulation parameters such as binary organic solvent composition and emulsifier types were evaluated on the basis of their effects on particle size and size distribution. PLNs had a strong dependency on the surface tension, intrinsic viscosity and volatilization rate of binary organic solvents and the hydrophilicity/hydrophobicity of emulsifiers. Acetone-methanol system together with pluronic F68 as emulsifier was proved to obtain the smallest particle size. Then the PLNs with different particle sizes were used to investigate how particle size at nanoscale affects interacted with tumor cells. As particle size got smaller, cellular uptake increased in tumor cells and PLNs with particle size of ~120 nm had the highest cellular uptake and fastest release rate. The paclitaxel (PTX)-loaded PLNs showed a size-dependent inhibition of tumor cell growth, which was commonly influenced by cellular uptake and PTX release. The PLNs would provide a useful means to further elucidate roles of particle size on delivery system of hydrophobic drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Emulsifier of Arthrobacter RAG-1: specificity of hydrocarbon substrate.

PubMed Central

Rosenberg, E; Perry, A; Gibson, D T; Gutnick, D L

1979-01-01

The purified extracellular emulsifying factor produced by Arthrobacter RAG-1 (EF-RAG) emulsified light petroleum oil, diesel oil, and a variety of crude oils and gas oils. Although kerosine and gasoline were emulsified poorly by EF-RAG, they were converted into good substrates for emulsification by addition of aromatic compounds, such as 2-methylnaphthalene. Neither aromatic nor aliphatic fractions of crude oil were emulsified by EF-RAG; however, mixtures containing both fractions were emulsified. Pure aliphatic or aromatic hydrocarbons were emulsified poorly by EF-RAG. Binary mixtures containing an aliphatic and an aromatic hydrocarbon, however, were excellent substrates for EF-RAG-induced emulsification. Of a variety of alkylcyclohexane and alkylbenzene derivatives tested, only hexyl- or heptylbenzene and octyl- or decylcyclohexane were effectively emulsified by EF-RAG. These data indicate that for EF-RAG to induce emulsification of hydrocarbons in water, the hydrocarbon substrate must contain both aliphatic and cyclic components. With binary mixtures of methylnaphthalene and hexadecane, maximum emulsion was obtained with 25% hexadecane. PMID:453821

Relative bioavailability of iron and folic acid from a new powdered supplement compared to a traditional tablet in pregnant women

PubMed Central

Hartman-Craven, Brenda; Christofides, Anna; O'Connor, Deborah L; Zlotkin, Stanley

2009-01-01

Background Deficiencies of iron and folic acid during pregnancy can lead to adverse outcomes for the fetus, thus supplements are recommended. Adherence to current tablet-based supplements is documented to be poor. Recently a powdered form of micronutrients has been developed which may decrease side-effects and thus improve adherence. However, before testing the efficacy of the supplement as an alternate choice for supplementation during pregnancy, the bioavailability of the iron needs to be determined. Our objective was to measure the relative bioavailability of iron and folic acid from a powdered supplement that can be sprinkled on semi-solid foods or beverages versus a traditional tablet supplement in pregnant women. Methods Eighteen healthy pregnant women (24 – 32 weeks gestation) were randomized to receive the supplements in a crossover design. Following ingestion of each supplement, the changes (over baseline) in serum iron and folate over 8 hours were determined. The powdered supplement contained 30 mg of iron as micronized dispersible ferric pyrophosphate with an emulsifier coating and 600 μg folic acid; the tablet contained 27 mg iron from ferrous fumarate and 1000 μg folic acid. Results Overall absorption of iron from the powdered supplement was significantly lower than the tablet (p = 0.003). There was no difference in the overall absorption of folic acid between supplements. Based on the differences in the area under the curve and doses, the relative bioavailability of iron from powdered supplement was lower than from the tablet (0.22). Conclusion The unexpected lower bioavailability of iron from the powdered supplement is contrary to previously published reports. However, since pills and capsules are known to be poorly accepted by some women during pregnancy, it is reasonable to continue to explore alternative micronutrient delivery systems and forms of iron for this purpose. Trial Registration ClinicalTrials.gov NCT00789490 PMID:19635145

Using oily wastewater emulsified fuel in boiler: energy saving and reduction of air pollutant emissions.

PubMed

Chen, Chun-Chi; Lee, Wen-Jhy

2008-01-01

The limited data for using emulsified oil have demonstrated its effectiveness in reducing flue gas pollutant emissions. The presence of a high concentration of toxic organic compounds in industrial wastewaters always presents significant problems. Therefore, this study was undertaken by using wastewater with COD of 9600 mg/L and total petroleum hydrocarbons-gasoline 440 mg/L for making an emulsified oil (wastewater content 20% with 0.1% surfactant) to evaluate the extent of reductions in both criteria pollutants and polycyclic aromatic hydrocarbons. For comparison, two other systems (heavy oil fuel and water-emulsified oil) were also conducted. The wastewater-emulsified oil fuel results in significant reductions in particulate matter (PM), NO(x), SO2, and CO as compared to heavy oil fuel and similar to those from water/oil emulsified fuel; for PM, it is better in wastewater-emulsified oil. The reductions of total PAH flue gas emissions are 38 and 30% for wastewater- and water-emulsified fuel, respectively; they are 63 and 44% for total BaP(eq), respectively. In addition to reducing flue gas pollutant emissions, the results also demonstrate that the use of wastewater-emulsified fuel in boiler operation provides several advantages: (1) safe disposal of industrial wastewater; and (2) energy savings of about 13%. Thus, wastewater/oil-emulsified fuel is highly suitable for use in boilers.

Solubility of ocular therapeutic agents in self-emulsifying oils. I. Self-emulsifying oils for ocular drug delivery: solubility of indomethacin, aciclovir and hydrocortisone.

PubMed

Czajkowska-Kośnik, Anna; Sznitowska, Małgorzata

2009-01-01

Self-emulsifying drug delivery systems (SEDDS) were prepared by dissolving Cremophor EL, Tween 20, Tween 80 and Span 80 (1% or 5%) in oils (Miglyol 812 or castor oil). Solubilities of three ophthalmic drugs, namely aciclovir, hydrocortisone and indomethacin were determined in these systems. In addition, the effect of a small amount of water (0.5% and 2%) on solubilization properties of the systems was estimated. Of the three substances, indomethacin showed the best solubility in Miglyol while aciclovir was practically insoluble in this oil. The surfactants usually increased drug solubility in the oily phase. Only Tween 20 was found to decrease the solubility of aciclovir and hydrocortisone in Miglyol. Addition of a small amount of water to the oil/surfactant system increased solubility of hydrocortisone, but not of indomethacin. The results of the current study may be utilized to design a suitable composition of SEDDS and allow continuation of research on this type of drug carriers.

SPILLCLEAN

EPA Pesticide Factsheets

Technical product bulletin: this surface washing agent for oil spill cleanups comes in either concentrate or original formula. Being a surfactant-type product, it emulsifies oil so it can then be lifted and separated from the hard surface.

An Overview of Pickering Emulsions: Solid-Particle Materials, Classification, Morphology, and Applications

PubMed Central

Yang, Yunqi; Fang, Zhiwei; Chen, Xuan; Zhang, Weiwang; Xie, Yangmei; Chen, Yinghui; Liu, Zhenguo; Yuan, Weien

2017-01-01

Pickering emulsion, a kind of emulsion stabilized only by solid particles locating at oil–water interface, has been discovered a century ago, while being extensively studied in recent decades. Substituting solid particles for traditional surfactants, Pickering emulsions are more stable against coalescence and can obtain many useful properties. Besides, they are more biocompatible when solid particles employed are relatively safe in vivo. Pickering emulsions can be applied in a wide range of fields, such as biomedicine, food, fine chemical synthesis, cosmetics, and so on, by properly tuning types and properties of solid emulsifiers. In this article, we give an overview of Pickering emulsions, focusing on some kinds of solid particles commonly serving as emulsifiers, three main types of products from Pickering emulsions, morphology of solid particles and as-prepared materials, as well as applications in different fields. PMID:28588490

Octenylsuccinate starch spherulites as a stabilizer for Pickering emulsions.

PubMed

Wang, Chan; Fu, Xiong; Tang, Chuan-He; Huang, Qiang; Zhang, Bin

2017-07-15

This study investigated structure and morphology of starch spherulites prepared from debranched waxy maize and waxy potato starches. Debranched waxy potato starch favored the formation of B-type crystals with longer branch chains (average chain length, 26.14), whereas A-type polymorphic aggregates were generated from debranched waxy maize under same recrystallization condition. Spherulites had smaller particle size distribution (D[3,2], ∼3.7μm), higher dissociation temperature (80-120°C) and crystallinity (80∼90%), compared to native waxy starches. Intact spherulites could be used as an edible particle emulsifier after modifying by octenylsuccinic anhydride (OSA). The emulsion produced using 2wt.% of octenylsuccinate (OS) starch spherulites as emulsifier was quite stable over 2months, and its Pickering emulsions displayed protective effect on stability of oil droplets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimization of chlorphenesin emulgel formulation.

PubMed

Mohamed, Magdy I

2004-10-11

This study was conducted to develop an emulgel formulation of chlorphenesin (CHL) using 2 types of gelling agents: hydroxypropylmethyl cellulose (HPMC) and Carbopol 934. The influence of the type of the gelling agent and the concentration of both the oil phase and emulsifying agent on the drug release from the prepared emulgels was investigated using a 2(3) factorial design. The prepared emulgels were evaluated for their physical appearance, rheological behavior, drug release, antifungal activity, and stability. Commercially available CHL topical powder was used for comparison. All the prepared emulgels showed acceptable physical properties concerning color, homogeneity, consistency, spreadability, and pH value. They also exhibited higher drug release and antifungal activity than the CHL powder. It was found that the emulsifying agent concentration had the most pronounced effect on the drug release from the emulgels followed by the oil phase concentration and finally the type of the gelling agent. The drug release from all the emulgels was found to follow diffusion-controlled mechanism. Rheological studies revealed that the CHL emulgels exhibited a shear-thinning behavior with thixotropy. Stability studies showed that the physical appearance, rheological properties, drug release, and antifungal activity in all the prepared emulgels remained unchanged upon storage for 3 months. As a general conclusion, it was suggested that the CHL emulgel formulation prepared with HPMC with the oil phase concentration in its low level and emulsifying agent concentration in its high level was the formula of choice since it showed the highest drug release and antifungal activity.

Understanding the effect of emulsifiers on bread aeration during breadmaking.

PubMed

Garzón, Raquel; Hernando, Isabel; Llorca, Empar; Rosell, Cristina M

2018-04-24

Much research has been done to explain the action of emulsifiers during breadmaking, but there is still plenty unknown to elucidate their functionality despite their diverse chemical structure. The aim of the present study was to provide some light on the role of emulsifiers on air incorporation into the dough and gas bubbles progress during baking and their relationship with bread features. Emulsifiers like diacetyl tartaric acid ester of monoglycerides (DATEM), sodium stearoyl lactylate (SSL), distilled monoglyceride (DMG-45 and DMG-75), lecithin and polyglycerol esters of fatty acids (PGEF) were tested in very hydrated doughs. Emulsifiers increase the maximum dough volume during proofing. Emulsifiers increase the number of bubbles incorporated during mixing, observing higher number of bubbles, particularly with PGEF. Major changes in dough occurred at 70 K when bubble size augmented, becoming more heterogeneous. DMG-75 produced the biggest bubbles. As a consequence, emulsifiers tend to increase the number of gas cells with lower size in the bread crumb, but led to greater crumb firmness, which suggested different interactions between emulsifiers and gluten, affecting protein polymerization during baking. The progress of the bubbles during baking allowed the differentiation of emulsifiers, which could explain their performance in breadmaking. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Swirling cavitation improves the emulsifying properties of commercial soy protein isolate.

PubMed

Yang, Feng; Liu, Xue; Ren, Xian'e; Huang, Yongchun; Huang, Chengdu; Zhang, Kunming

2018-04-01

Since emulsifying properties are important functional properties of soy protein, many physical, chemical, and enzymatic methods have been applied to treat soy protein to improve emulsifying properties. In this study, we investigated the effects of swirling cavitation at different pressures and for different times on emulsifying and physicochemical properties of soy protein isolate (SPI). The SPI treated with swirling cavitation showed a significant decrease in particle size and increase in solubility. Emulsions formed from treated SPI had higher emulsifying activity and emulsifying stability indexes, smaller oil droplet sizes, lower flocculation indexes, higher adsorbed proteins, lower interfacial protein concentrations, and lower creaming indexes than those formed from untreated SPI, indicating that swirling cavitation improved the emulsifying properties of the SPI. Furthermore, swirling cavitation treatment significantly enhanced the surface hydrophobicity, altered the disulfide bond and exposed sulfhydryl group contents of the SPI. The secondary structure of the SPI was also influenced by swirling cavitation, with an increase in β-sheet content and a decrease in α-helix, β-turn, and random coil contents. In addition, several significant correlations between physicochemical and emulsifying properties were revealed by Pearson correlation analysis, suggesting that the physicochemical changes observed in treated SPI, including the decreased particle size, increased solubility and surface hydrophobicity, and enhanced β-sheet formation, may explain the improved emulsifying properties of the isolate. Thus, our findings implied that swirling cavitation treatment may be an effective technique to improve the emulsifying properties of SPI. Copyright © 2017 Elsevier B.V. All rights reserved.

Emulsification of hydrocarbons by subsurface bacteria

USGS Publications Warehouse

Francy, D.S.; Thomas, J.M.; Raymond, R.L.; Ward, C.H.

1991-01-01

Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been the dominant factor which selected for and encouraged growth of emulsifiers; exposure to hydrocarbon was also important. Biostimulated microorganisms were better emulsifiers of aviation fuel (the contaminant hydrocarbon) than of heavier hydrocarbon to which they were not previously exposed. By measuring surface tension changes of culture broths, 11 out of 41 emulsifiers tested were identified as possible biosurfactant producers and two isolates produced large surface tension reductions indicating the high probability of biosurfactant production.Biosurfactants have potential for use in enhancement of in situ biorestoration by increasing the bioavailability of contaminants. Microorganisms isolated from biostimulated, contaminated and uncontaminated zones at the site of an aviation fuel spill and hydrocarbon-degrading microorganisms isolated from sites contaminated with unleaded gasoline were examined for their abilities to emulsify petroleum hydrocarbons. Emulsifying ability was quantified by a method involving agitation and visual inspection. Biostimulated-zone microbes and hydrocarbon-degrading microorganisms were the best emulsifiers as compared to contaminated and uncontaminated zone microbes. Biostimulation (nutrient and oxygen addition) may have been the dominant factor which selected for and encouraged growth of emulsifiers; exposure to hydrocarbon was also important. Biostimulated microorganisms were better emulsifiers of aviation fuel (the contaminant hydrocarbon) than of heavier hydrocarbon to which they were not previously exposed. By measuring surface tension changes of culture broths, 11 out of 41 emulsifiers tested were identified as possible biosurfactant producers and two isolates produced large surface tension reductions, indicating a high probability of biosurfactant production.

Production of a Health-Beneficial Food Emulsifier by Enzymatic Partial Hydrolysis of Phospholipids Obtained from the Head of Autumn Chum Salmon.

PubMed

Shah, A K M Azad; Nagao, Toshihiro; Kurihara, Hideyuki; Takahashi, Koretaro

2017-02-01

Phospholipids and their partial hydrolysates, namely lysophospholipids (LPLs), have been widely used in food, pharmaceutical, and cosmetic products as highly efficient emulsifiers. This study was conducted to produce docosahexaenoic acid (DHA)-esterified LPLs by enzymatic modification of phospholipids obtained from the head of autumn chum salmon (Oncorhynchus keta). The emulsifying properties of the obtained LPLs were also evaluated. Two different types of substrates of salmon head phospholipids were prepared via silica gel and cold acetone precipitation. Enzymatic partial hydrolysis was carried out using immobilized phospholipase A 1 (PLA 1 ) and Lipozyme RM IM. Results showed that the increase in DHA in the LPLs was much higher in the silica-separated phospholipids than in the acetone-precipitated phospholipids. When silica-separated phospholipids were used as the substrate, the DHA content of the LPLs increased from 23.1% to 40.6% and 42.6% after 8 h of partial hydrolysis with Lipozyme RM IM and immobilized PLA 1 , respectively. The yield of the LPLs was comparatively higher in the Lipozyme RM IM than in the immobilized PLA 1 hydrolysis reaction. The critical micelle concentration values of the LPLs and purified lysophosphatidylcholine (LPC) were 100 mg/L and 5 mg/L, respectively. The surface tension values of the LPLs and LPC were reduced to 30.0 mN/m and 30.5 mN/m, respectively. The hydrophilic-lipophilic balance of the LPLs and LPC were 6.0 and 9.4, respectively. Based on the emulsifying properties observed, we conclude that LPLs derived from the phospholipids of salmon head lipids could be used as a health-beneficial emulsifier in the food industry.

Self-emulsifying drug delivery systems (SEDDS): formulation development, characterization, and applications.

PubMed

Singh, Bhupinder; Bandopadhyay, Shantanu; Kapil, Rishi; Singh, Ramandeep; Katare, O

2009-01-01

Self-emulsifying drug delivery systems (SEDDS) possess unparalleled potential in improving oral bioavailability of poorly water-soluble drugs. Following their oral administration, these systems rapidly disperse in gastrointestinal fluids, yielding micro- or nanoemulsions containing the solubilized drug. Owing to its miniscule globule size, the micro/nanoemulsifed drug can easily be absorbed through lymphatic pathways, bypassing the hepatic first-pass effect. We present an exhaustive and updated account of numerous literature reports and patents on diverse types of self-emulsifying drug formulations, with emphasis on their formulation, characterization, and systematic optimization strategies. Recent advancements in various methodologies employed to characterize their globule size and shape, ability to encapsulate the drug, gastrointestinal and thermodynamic stability, rheological characteristics, and so forth, are discussed comprehensively to guide the formula-tor in preparing an effective and robust SEDDS formulation. Also, this exhaustive review offers an explicit discussion on vital applications of the SEDDS in bioavailability enhancement of various drugs, outlining an overview on myriad in vitro, in situ, and ex vivo techniques to assess the absorption and/ or permeation potential of drugs incorporated in the SEDDS in animal and cell line models, and the subsequent absorption pathways followed by them. In short, the current article furnishes an updated compilation of wide-ranging information on all the requisite vistas of the self-emulsifying formulations, thus paving the way for accelerated progress into the SEDDS application in pharmaceutical research.

[Study on extracting and separating curcuminoids from Curcuma longa rhizome using ultrasound strengthen by microemulsion].

PubMed

Yue, Chun-Hua; Zheng, Li-Tao; Guo, Qi-Ming; Li, Kun-Ping

2014-05-01

To establish a new method for the extraction and separation of curcuminoids from Curcuma longa rhizome by cloud-point preconcentration using microemulsions as solvent. The spectrophotometry was used to detect the solubility of curcumin in different oil phase, emulsifier and auxiliary emulsifier, and the microemulsion prescription was used for false three-phase figure optimization. The extraction process was optimized by uniform experiment design. The curcuminoids were separated from microemulsion extract by cloud-point preconcentration. Oil phase was oleic acid ethyl ester; Emulsifier was OP emulsifier; Auxiliary emulsifier was polyethylene glycol(peg) 400; The quantity of emulsifier to auxiliary emulsifier was the ratio of 5: 1; Microemulsion prescription was water-oleic acid ethyl ester-mixed emulsifier (0.45:0.1:0.45). The optimum extraction process was: time for 12.5 min, temperature of 52 degrees C, power of 360 W, frequency of 400 kHz, and the liquid-solid ratio of 40:1. The extraction rate of curcuminoids was 92.17% and 86.85% in microemulsion and oil phase, respectively. Curcuminoids is soluble in this microemulsion prescription with good extraction rate. This method is simple and suitable for curcuminoids extraction from Curcuma longa rhizome.

Influence of Emulsified Asphalt on the Mechanical Property and Microstructure of Cement-Stabilized Gravel under Freezing and Thawing Cycle Conditions.

PubMed

Wang, Yiqi; Tan, Yiqiu; Guo, Meng; Wang, Xinglong

2017-05-06

Properties of cement-stabilized gravel modified by emulsified asphalt under freezing and thawing cycle conditions were investigated by adjusting the dosage of cement. Mercury intrusion porosimetry (MIP) and Scanning electron microscopy (SEM) were introduced to analyze the influential mechanism. The results indicate that cement emulsified asphalt stabilized gravel with 5 wt % of cement performed well in both mechanics and frost-resistance. Although the addition of emulsified asphalt would lead to a partial decrease of strength, it can extend the process of strength loss and improve the freezing resistance. The main reason for this is that the permeability can be improved by the filling effects of emulsified asphalt. The frost-heave stress caused by the phase transition of water can also be remitted by emulsified asphalt, the elasticity modulus of which is much lower than the matrix. The generating speed of the micro crack can also be slowed down by emulsified asphalt.

7 CFR 58.631 - Emulsifiers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.631 Emulsifiers. Emulsifiers shall be clean and wholesome and consist of one or more of those...

7 CFR 58.631 - Emulsifiers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.631 Emulsifiers. Emulsifiers shall be clean and wholesome and consist of one or more of those...

Impact of Phospholipids and Tocopherols on the Oxidative Stability of Soybean Oil-in-Water Emulsions.

PubMed

Samdani, Gautam K; McClements, D Julian; Decker, Eric A

2018-04-18

Phospholipids have been shown to act synergistically with tocopherols and delay lipid oxidation in bulk oil. The synergistic activity between phospholipids and tocopherols is due to the ability of amino-group-containing phospholipids (e.g., phosphatidylethanolamine (PE) and phosphatidylserine (PS)) to convert oxidized tocopherol back into tocopherols. This study shows the effect of PE and PS on the antioxidant activity of different tocopherol homologues in oil-in-water emulsions. Effect of emulsifier type on the interaction between tocopherols and phospholipids was also studied. δ-Tocopherol and PE exhibited greater antioxidant activity as compared to α-tocopherol and PE. PS displayed 1.5-3 times greater synergism than PE with Tween 20 as emulsifier whereas both PE and PS had a similar antioxidant activity in the presence of α-tocopherol when bovine serum albumin was used as the emulsifier. This study is the first to show that PE and PS can act synergistically with tocopherols to inhibit lipid oxidation in oil-in-water emulsions and can present a new clean label antioxidant strategy for food emulsions.

The major proteins of the seed of the fruit of the date palm (Phoenix dactylifera L.): Characterisation and emulsifying properties.

PubMed

Akasha, Ibrahim; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R

2016-04-15

Proteins were extracted from the seeds of the fruit of the date palm. Proteomic analysis and SDS-PAGE electrophoresis of the extracted proteome suggested it is composed predominantly of the storage proteins glycinin and β-conglycinin, although over 300 proteins were detected, 91 of which were identified with confidence. In terms of protein type, the largest numbers of proteins were associated, not unexpectedly, with metabolism and energy functions, which reflected the requirements of the germinating and growing embryonic plant. The emulsifying properties of the extracted proteins were determined. Date seed protein exhibited a lower emulsifying activity than either whey protein concentrate or soy protein isolate, at each of the pH values tested. However, the stability of the emulsions produced with all three proteins was very similar at the different pH values. This combination of large emulsion droplet size and high emulsion stability properties suggested that the date proteins may adsorb as large protein oligomers. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of endogenous lipids in the emulsifying properties of cocoa

NASA Astrophysics Data System (ADS)

Gould, Joanne; Furse, Samuel; Wolf, Bettina

2016-03-01

This paper describes a study in which the emulsifying properties of cocoa material with and without its lipid fraction were explored. This study was motivated by the commercial interest in naturally-occurring particulate emulsifiers as opposed to the chemically modified emulsifying particles presently available for commercial use. The hypothesis was that endogenous lipids from cocoa were responsible for driving the formation of stable oil-in-water (o/w) emulsions. The data presented includes relative quantification of phospholipids from different commercially available cocoa material using 31P NMR spectroscopy and analyses of the emulsifying power of delipidified cocoa material. The commercially available cocoa material comprised several phospholipids, with phosphatidylcholine being the most abundant in all samples. Dispersions of delipidified cocoa material were found to drive the formation of o/w emulsions despite the absence of lipids. We therefore concluded that the emulsifying behaviour of cocoa material is not entirely reliant upon the endogenous lipids. This suggests that cocoa material may have a new and potentially widespread use in industrial food preparation and may inform manufacturing strategies for novel food grade emulsifiers.

Efficiency and protective effect of encapsulation of milk immunoglobulin G in multiple emulsion.

PubMed

Chen, C C; Tu, Y Y; Chang, H M

1999-02-01

Milk immunoglobulin G (IgG), separated with protein G affinity chromatography, and IgG in colostral whey were encapsulated by 0.5% (w/v) of Tween 80, sucrose stearate, or soy protein, which were used as secondary emulsifiers in the water in oil in water type multiple emulsion. The residual contents of separated IgG and IgG in colostral whey, ranging from 58.7 to 49.7% and from 13.2 to 21.3%, respectively, in the inner water phase (water phase surrounded by oil phase) with emulsifiers were determined by ELISA. However, the emulsion stability decreased after 24 h, and the residual IgG content in the inner water phase was lowered. Encapsulation of IgG in the multiple emulsion increased the stability of separated IgG against acid (pH 2.0) and alkali (pH 12.0) by 21-56% and 33-62%, respectively, depending on the emulsifier used. Moreover, multiple emulsion also provided a remarkable protective effect on separated IgG stability against proteases. The residual contents of separated IgG in multiple emulsion, using Tween 80 as secondary emulsifier, incubated for 2 h with pepsin (pH 2.0) and trypsin and chymotrypsin (pH 7.6) (enzyme/substrate = 1/20) were 35.4, 72.5, and 82.3%, whereas those of separated IgG in enzyme solution were only 7.2, 33. 1, and 35.2%, respectively. However, the separated IgG loss during the preparation of multiple emulsion was almost 41-50%.

Efficient breaking of water/oil emulsions by a newly isolated de-emulsifying bacterium, Ochrobactrum anthropi strain RIPI5-1.

PubMed

Mohebali, Ghasemali; Kaytash, Ashk; Etemadi, Narges

2012-10-01

Water-oil emulsions occur throughout oil production, transportation, and processing. The breaking of the water/oil emulsion improves oil quality and as a consequence chemically synthesized de-emulsifiers are commonly used in the petroleum industries. Microbial de-emulsifiers represent potential alternatives to the chemicals and may become important products for petroleum industries. The main goal of this work was isolation, identification, and characterization of an efficient de-emulsifying bacterium. Following a multi-step enrichment programme a de-emulsifying bacterium, Ochrobactrum anthropi strain RIPI5-1was isolated from the oil-polluted sandy bank of Siri Island, Iran. The presence of an oil phase in growth medium was found to be unnecessary for production of the de-emulsifier. The de-emulsifying activity of both the whole culture and the cells of this strain was examined using a model multiple water-crude oil (w/o/w) emulsion. This w/o/w emulsion was used for the first time in microbial de-emulsification research. Whole cells of strain RIPI5-1 exhibited high de-emulsifying activity during the late-exponential growth and stationary phases; de-emulsifying activity of the whole culture was highest during the early-exponential growth phase. The time course of de-emulsification by whole culture and whole cells of strain RIPI5-1 was investigated; the initial rate (DeI(1)) of breaking of the multiple water-crude oil emulsion by whole culture and whole cells was calculated as 11% and 54%, respectively. However, overall de-emulsification (DeI(8.5)) for whole culture and whole cells was calculated as 63% and 72%, respectively. A clear correlation was observed between cell surface hydrophobicity and the de-emulsifying activity of whole cells. With the water/kerosene emulsion, emulsion half-life (t(1/2)) was found to be <0.5h. The potential activity of this strain was also explained using a complex oilfield emulsion. Copyright © 2012 Elsevier B.V. All rights reserved.

Enhancement of emulsifier production by Curvularia lunata in cadmium, zinc and lead presence.

PubMed

Paraszkiewicz, Katarzyna; Frycie, Aleksandra; Słaba, Mirosława; Długoński, Jerzy

2007-10-01

The influence of cadmium, zinc and lead on fungal emulsifier synthesis and on the growth of filamentous fungus Curvularia lunata has been studied. Tolerance to heavy metals established for C. lunata was additionally compared with the sensitivity exhibited by strains of Curvularia tuberculata and Paecilomyces marquandii-fungi which do not secrete compounds of emulsifying activity. Although C. lunata, as the only one out of all studied fungi, exhibited the lowest tolerance to heavy metals when grown on a solid medium (in conditions preventing emulsifier synthesis), it manifested the highest tolerance in liquid culture - in conditions allowing exopolymer production. Cadmium, zinc and lead presented in liquid medium up to a concentration of 15 mM had no negative effect on C. lunata growth and stimulated emulsifier synthesis. In the presence of 15 mM of heavy metals, both the emulsifier and 24-h-old growing mycelium exhibited maximum sorption capacities, which were determined as 18.2 +/- 2.67, 156.1 +/- 10.32 mg g(-1) for Cd2+, 22.2 +/- 3.40, 95.2 +/- 14.21 mg g(-1) for Zn2+ and 51.1 +/- 1.85, 230.0 +/- 28.47 mg g(-1) for Pb2+ respectively. The results obtained by us in this work indicate that the emulsifier acts as a protective compound increasing the ability of C. lunata to survive in heavy metal polluted environment. Enhancement of exopolymer synthesis in the presence of Cd2+, Zn2+ and Pb2+ may also suggest, at least to some extent, a metal-specific nature of emulsifier production in C. lunata. Due to accumulation capability and tolerance to heavy metals, C. lunata mycelium surrounded by the emulsifier could be applied for toxic metal removal.

[Treatment of wrinkles of the upper lip by emulsified fat or "Nanofat": Biological and clinical study about 4 cases].

PubMed

Mesguich Batel, F; Bertrand, B; Magalon, J; François, P; Velier, M; Veran, J; Mallet, S; Jouve, E; Sabatier, F; Casanova, D

2018-02-01

Emulsified fat injection showed its interest in aesthetic facial surgery. The adipose tissue harvested is mechanically emulsified and filtered. The suspension obtained is injected into the dermis through small diameter needles (27 to 30 gauges). The objective of our study was to evaluate the biological composition of emulsified fat and its clinical effectiveness in the treatment of peri-oral wrinkles in 4 patients aged 50 to 59 years. Each patient received an intradermal injection of emulsified fat in the peri-oral wrinkles prepared from abdominal fat under local anesthesia. The cell viability, stromal vascular fraction (FVS) composition in emulsified fat and the adipocyte differentiation capacity of mesenchymal stem cells (MSC) were studied. The clinical results were evaluated by standardized photographs, 3D microphotography, confocal microscopy, and self-evaluation of patient satisfaction over a period of 4 months. The biological study of the emulsified fat found a lysis of all the adipocytes. The mean number of FVS cells was 126,330±2758 cells by cc of emulsified fat with preserved cell viability (85.1±6.84 %) and a good proportion of regeneratives cells (18.77±6.2 %). The clinical study found a tendency to decrease the volume of wrinkles on standardized photography and 3D microphotography no significative. Patients were satisfied with treatment with an average score of 7±1.15/10 to 4 months. Intradermal injection of emulsified fat seems to be an interesting treatment of face wrinkles. Our study has shown its safety, but additional studies seems necessary to confirm its clinical efficacy. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome.

PubMed

Chassaing, Benoit; Koren, Omry; Goodrich, Julia K; Poole, Angela C; Srinivasan, Shanthi; Ley, Ruth E; Gewirtz, Andrew T

2015-03-05

The intestinal tract is inhabited by a large and diverse community of microbes collectively referred to as the gut microbiota. While the gut microbiota provides important benefits to its host, especially in metabolism and immune development, disturbance of the microbiota-host relationship is associated with numerous chronic inflammatory diseases, including inflammatory bowel disease and the group of obesity-associated diseases collectively referred to as metabolic syndrome. A primary means by which the intestine is protected from its microbiota is via multi-layered mucus structures that cover the intestinal surface, thereby allowing the vast majority of gut bacteria to be kept at a safe distance from epithelial cells that line the intestine. Thus, agents that disrupt mucus-bacterial interactions might have the potential to promote diseases associated with gut inflammation. Consequently, it has been hypothesized that emulsifiers, detergent-like molecules that are a ubiquitous component of processed foods and that can increase bacterial translocation across epithelia in vitro, might be promoting the increase in inflammatory bowel disease observed since the mid-twentieth century. Here we report that, in mice, relatively low concentrations of two commonly used emulsifiers, namely carboxymethylcellulose and polysorbate-80, induced low-grade inflammation and obesity/metabolic syndrome in wild-type hosts and promoted robust colitis in mice predisposed to this disorder. Emulsifier-induced metabolic syndrome was associated with microbiota encroachment, altered species composition and increased pro-inflammatory potential. Use of germ-free mice and faecal transplants indicated that such changes in microbiota were necessary and sufficient for both low-grade inflammation and metabolic syndrome. These results support the emerging concept that perturbed host-microbiota interactions resulting in low-grade inflammation can promote adiposity and its associated metabolic effects. Moreover, they suggest that the broad use of emulsifying agents might be contributing to an increased societal incidence of obesity/metabolic syndrome and other chronic inflammatory diseases.

Arabinoxylan-lipids-based edible films and coatings. 2. Influence of sucroester nature on the emulsion structure and film properties.

PubMed

Phan The, D; Péroval, C; Debeaufort, F; Despré, D; Courthaudon, J L; Voilley, A

2002-01-16

This work is a contribution to better knowledge of the influence of the structure of films on their functional properties obtained from emulsions based on arabinoxylans, hydrogenated palm kernel oil (HPKO), and emulsifiers. The sucroesters (emulsifiers) have a great effect on the stabilization of the emulsified film structure containing arabinoxylans and hydrogenated palm kernel oil. They improve the moisture barrier properties. Several sucroesters having different esterification degrees were tested. Both lipophilic (90% of di and tri-ester) and hydrophilic (70% of mono-ester) sucrose esters can ensure the stability of the emulsion used to form the film, especially during preparation and drying. These emulsifiers confer good moisture barrier properties to emulsified films.

Emulsifying properties of succinylated arabinoxylan-protein gum produced from corn ethanol residuals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiang, Zhouyang; Runge, Troy

This study investigated the possibilities of making valuable products from corn ethanol byproducts and providing the beverage industries more variety of high quality emulsifiers other than gum arabic. An arabinoxylan-protein gum (APG) was extracted from distillers' grains (DG), a low-value corn ethanol byproduct, and modified through acylation with succinic anhydride. The effects of pH and degree of substitution (DS) on the emulsifying properties of succinylated APG, referred to as SAPG, were investigated. Emulsion particle size and stability of APG and gum arabic were comparable at pH 3.5–6.5. Succinylation could enhance the emulsifying properties of APG. Compared to gum arabic, atmore » pH < 5, SAPG emulsions had larger particle size but comparable stability, whereas at pH > 5, SAPG had much smaller particle size and better stability than gum arabic. The results suggested that SAPG, compared to gum arabic, could be a comparable emulsifier at low pH values and a better emulsifier at neutral pH values.« less

Emulsifying properties of succinylated arabinoxylan-protein gum produced from corn ethanol residuals

DOE PAGES

Xiang, Zhouyang; Runge, Troy

2015-07-21

This study investigated the possibilities of making valuable products from corn ethanol byproducts and providing the beverage industries more variety of high quality emulsifiers other than gum arabic. An arabinoxylan-protein gum (APG) was extracted from distillers' grains (DG), a low-value corn ethanol byproduct, and modified through acylation with succinic anhydride. The effects of pH and degree of substitution (DS) on the emulsifying properties of succinylated APG, referred to as SAPG, were investigated. Emulsion particle size and stability of APG and gum arabic were comparable at pH 3.5–6.5. Succinylation could enhance the emulsifying properties of APG. Compared to gum arabic, atmore » pH < 5, SAPG emulsions had larger particle size but comparable stability, whereas at pH > 5, SAPG had much smaller particle size and better stability than gum arabic. The results suggested that SAPG, compared to gum arabic, could be a comparable emulsifier at low pH values and a better emulsifier at neutral pH values.« less

Study on adsorption properties of synthetic materials on marine emulsified oil

NASA Astrophysics Data System (ADS)

Zhang, Zhaoyang; Peng, Shitao; Wang, Xiaoli; Zhou, Ran; Luo, Lei

2018-02-01

As an effective measure for marine oil spill recovery, adsorption treatment can be adopted in areas where mechanical recovery is not applicable. This experiment is mainly aimed at studying the adsorption properties of synthetic materials on emulsified oil. The emulsified oil was prepared by simulating the emulsification process of marine oil spill via a wave-current flume, and the adsorption weights of synthetic materials on emulsified oil were obtained by performing a field adsorption experiment. Polypropylene, nano-polypropylene and hydrophobic melamine sponge were tested by adsorbing a variety of emulsified oils according to the Adsorption Property Test Method (Version F-726) defined by ASTM. Their adsorption weights on emulsified oil (with initial thickness of 5 mm and water content of 20.86%) are 5.42 g/g, 23.5 g/g and 82.15g/g, respectively, which, compared with that on gear oil in the initial state, are respective decreases of 46.39%, 19.88% and 11.84%, demonstrating obvious decreases in their adsorption performances.

Effect of extruded wheat flour as a fat replacer on batter characteristics and cake quality.

PubMed

Román, Laura; Santos, Isabel; Martínez, Mario M; Gómez, Manuel

2015-12-01

The effects of three levels of fat replacement (1/3, 2/3, and 3/3) by extruded flour paste and the effects of the presence of emulsifier on layer cake batter characteristics and final cake quality were studied. Replacement of oil by extruded flour paste modified the batter density and microscopy, reducing the number of air bubbles and increasing their size, while emulsifier incorporation facilitated air entrapment in batter. Emulsifier addition also increased the elastic and viscous moduli of the batter, while oil reduction resulted in a less structured batter. Emulsifier incorporation leads to good quality cakes, minimizing the negative effect of oil reduction, maintaining the volume and reducing the hardness of cakes. Furthermore, consumer acceptability of the reduced fat cakes was improved by the addition of emulsifier. Thus, the results confirmed the positive effect of partial oil substitution (up to 2/3) by extruded flour paste on the quality of reduced fat cakes when emulsifier was incorporated.

Preparation and evaluation of Vinpocetine self-emulsifying pH gradient release pellets.

PubMed

Liu, Mengqi; Zhang, Shiming; Cui, Shuxia; Chen, Fen; Jia, Lianqun; Wang, Shu; Gai, Xiumei; Li, Pingfei; Yang, Feifei; Pan, Weisan; Yang, Xinggang

2017-11-01

The main objective of this study was to develop a pH gradient release pellet with self-emulsifying drug delivery system (SEDDS), which could not only improve the oral bioavailability of Vinpocetine (VIN), a poor soluble drug, but reduce the fluctuation of plasma concentration. First, the liquid VIN SEDDS formulation was prepared. Then the self-emulsifying pH gradient release pellets were prepared by extrusion spheronization technique, and formulation consisted by the liquid SEDDS, absorbent (colloidal silicon dioxide), penetration enhancer (sodium chloride), microcrystalline cellulose, ethyl alcohol, and three coating materials (HPMC, Eudragit L30D55, Eudragit FS30D) were eventually selected. Three kinds of coated pellets were mixed in capsules with the mass ratio of 1:1:1. The release curves of capsules were investigated in vitro under the simulated gastrointestinal conditions. In addition, the oral bioavailability and pharmacokinetics of VIN self-emulsifying pH gradient release pellets, commercial tablets and liquid VIN SEDDS were evaluated in Beagle dogs. The oral bioavailability of self-emulsifying pH gradient release pellets was about 149.8% of commercial VIN tablets, and it was about 86% of liquid VIN SEDDS, but there were no significant difference between liquid SEDDS and self-emulsifying pH gradient release pellets. In conclusion, the self-emulsifying pH gradient release pellets could significantly enhance the absorption of VIN and effectively achieve a pH gradient release. And the self-emulsifying pH gradient release pellet was a promising method to improve bioavailability of insoluble drugs.

7 CFR 58.722 - Emulsifying agents.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.722 Emulsifying agents. Emulsifying agents shall be those permitted by the Food and Drug Administration for the specific pasteurized process cheese product, and shall be free from extraneous material...

7 CFR 58.722 - Emulsifying agents.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.722 Emulsifying agents. Emulsifying agents shall be those permitted by the Food and Drug Administration for the specific pasteurized process cheese product, and shall be free from extraneous material...

Development of Pales Weevil Larvae on an Emulsified Synthetic Diet

Treesearch

H.A. Thomas

1971-01-01

The effect of adding an emulsifier to an artificial diet for pales weevil larvae was studied. The hypothesis was that fat-soluble ingredients would be better dispersed in the aqueous media, possibly leading to improved larval growth. The results suggest some Improvement occurred when the emulsifier was incorporated.

Emulsion of an in-situ surfactant in petroleum. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1983-12-01

Three emulsifiers were tested for their ability to reduce the viscosity of heavy oils. A reduction of 25% viscosity is achieved using polybutene. A reduction of 50% viscosity is achieved using a concentrated ionic detergent obtained from SANDOZ. The most promising emulsifiers is a lipopeptide. Preliminary studies show this emulsifier reduces the viscosity of heavy oils by as much as 80%. It is also able to reduce the surface tension of water by 35%. This emulsifier is also biodegradable and less toxic than synthetic surfactants. (DMC)

Effect of type of emulsifiers and antioxidants on oxidative stability, colour and fatty acid profile of low-fat beef burgers enriched with unsaturated fatty acids and phytosterols.

PubMed

Pennisi Forell, S C; Ranalli, N; Zaritzky, N E; Andrés, S C; Califano, A N

2010-10-01

Low-fat beef burgers were formulated using fresh lean meat, 9.9% oleic sunflower oil and 0.1% deodorized fish oil to obtain a product enriched in unsaturated fatty acids. The effect of two emulsifiers (whey proteins or egg white) and natural antioxidants (tocopherols and/or oregano-rosemary), as well as the influence of frozen storage on the oxidative stability, colour, and fatty acid (FA) profile was determined on the cooked products. Whey proteins protected better against oxidation than egg white, and tocopherols demonstrated an adequate antioxidant effect in formulations with egg white. For all the formulations the unsaturated/saturated FA ratio was higher than 5.8, showing a good lipid balance in the products. The consumption of 100g of the cooked product would provide 6% of the recommended daily intake of phytosterols suggested to decrease cholesterol and the risk of heart disease. Formulated low-fat burgers with pre-emulsified oils and phytosterols could be considered to be potentially functional foodstuffs. Copyright (c) 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

The Ratios of Pre-emulsified Duck Skin for Optimized Processing of Restructured Ham.

PubMed

Shim, Jae-Yun; Kim, Tae-Kyung; Kim, Young-Boong; Jeon, Ki-Hong; Ahn, Kwang-Il; Paik, Hyun-Dong; Choi, Yun-Sang

2018-02-01

The purpose of this study was to investigate the quality of duck ham formulated with duck skin through the pre-emulsification process. The experiments to investigate the quality characteristics of duck ham were carried out to measure proximate composition, cooking loss, emulsion stability, pH, color, texture profile analysis, apparent viscosity, and sensory characteristics. Duck ham was prepared with various ratios of duck skin in pre-emulsion as follows: Control (duct skin 30%), T1 (duck skin 20% + pre-emulsified duck skin 10%), T2 (duck skin 15% + pre-emulsified duck skin 15%), T3 (duck skin 10% + pre-emulsified duck skin 20%), and T4 (pre-emulsified duck skin 30%). As the ratio of duck skin to pre-emulsified skin changed, the quality of duck ham in terms of moisture content, fat content, cooking loss, emulsion stability, lightness, textural analysis, apparent viscosity, and overall acceptability changed. The moisture content of T2 was the highest ( p <0.05) and that of the control and T4 was the lowest ( p <0.05). The fat content of control was higher than all treatments ( p <0.05). T2 had the lowest values in cooking loss, total expressible fluid, fat separation, hardness, springiness, and gumminess ( p <0.05). The score of overall acceptability of all treatments with pre-emulsified skin was higher than control ( p <0.05). Therefore, the pre-emulsification process can improve the quality characteristics of duck ham and 1:1 ratio of duck skin and pre-emulsified skin was the proper ratio to improve the quality characteristics of duck ham.

Surface Enrichment by Conventional and Polymerizable Sulfated Nonylphenol Ethoxylate Emulsifiers in Water-Based Pressure-Sensitive Adhesive

Treesearch

Jilin Zhang; Yuxi Zhao; Matthew R. Dubay; Steven J. Severtson; Larry E. Gwin; Carl J. Houtman

2013-01-01

Comparisons of properties are made for pressure-sensitive adhesives (PSAs) generated via emulsion polymerization using both conventional and reactive emulsifiers. The emulsifiers are ammonium salts of sulfated nonylphenol ethoxylates with similar chemical structures and hydrophilic−lipophilic balances. The polymerizable surfactant possesses a reactive double...

21 CFR 172.834 - Ethoxylated mono- and diglycerides.

Code of Federal Regulations, 2011 CFR

2011-04-01

... emulsifier in whipped vegetable oil toppings and topping mixes Not to exceed 0.45 percent by weight of the finished whipped vegetable oil toppings. 4. As an emulsifier in icings and icing mixes Not to exceed 0.5... by weight of the finished frozen desserts. 6. As an emulsifier in edible vegetable fat-water...

Food-grade microemulsions based on nonionic emulsifiers: media to enhance lycopene solubilization.

PubMed

Spernath, Aviram; Yaghmur, Anan; Aserin, Abraham; Hoffman, Roy E; Garti, Nissim

2002-11-06

Water-dilutable food-grade microemulsions consisting of ethoxylated sorbitan esters, and in some cases blended with other emulsifiers, water, (R)-(+)-limonene, ethanol, and propylene glycol, have been prepared. These microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. Lycopene, an active natural lipophilic antioxidant from tomato, has solubilized in water-in-oil, bicontinuous, and oil-in-water types of microemulsions up to 10 times the oil [(R)-(+)-limonene] dissolution capacity. The effects of aqueous-phase dilution, nature of surfactant (hydrophilic-lypophilic balance), and mixed surfactant on solubilization capacity and solubilization efficiency were studied. Structural aspects studied by self-diffusion NMR were correlated to the solubilization capacity, and transformational structural changes were identified.

Foaming and emulsifying properties of pectin isolated from different plant materials

NASA Astrophysics Data System (ADS)

Yancheva, Nikoleta; Markova, Daniela; Murdzheva, Dilyana; Vasileva, Ivelina; Slavov, Anton

2016-03-01

The foaming and emulsifying properties of pectins obtained from waste rose petals, citrus pressings, grapefruit peels and celery were studied. It was found that the highest foaming capacity showed pectin derived from celery. The effect of pectin concentration on the foaming capacity of pectin solutions was investigated. For all the investigated pectins increasing the concentration led to increase of the foaming capacity. Emulsifying activity and emulsion stability of model emulsion systems (50 % oil phase) with 0.6 % pectic solutions were determined. The highest emulsifying activity and stability showed pectin isolated by dilute acid extraction from waste rose petals.

Influence of high dose of phytase and an emulsifier on performance, apparent metabolisable energy and nitrogen retention in broilers fed on diets containing soy oil or tallow.

PubMed

Zaefarian, F; Romero, L F; Ravindran, V

2015-01-01

The effects of high dose of microbial phytase and an emulsifier on the performance, apparent metabolisable energy (AME) and nitrogen (N) retention in broilers fed on diets containing different fat sources were examined in a 5-week trial. Two fat sources (soy oil and tallow), two inclusion levels of E. coli phytase (500 or 1000 phytase units (FTU)/kg diet) and two inclusion levels of lysolecithin emulsifier (0 or 3.5 g/kg of diet) were evaluated in a 2 × 2 × 2 factorial arrangement of treatments. Throughout the 5-week trial, soy oil supplementation improved weight gain and feed per gain compared with tallow, but had no effect on feed intake. The high dose of phytase increased the weight gain and feed intake and lowered the feed per gain during d 1-21, but had no effect on performance parameters over the whole trial period. An effect of emulsifier was observed for feed intake during d 1-21 and over the whole trial period. Addition of emulsifier increased feed intake compared with diets without emulsifier. During weeks 1, 2, 3 and 5, birds fed on soy oil-based diets had higher nitrogen-corrected AME (AMEN) compared with those fed on tallow-based diets. During weeks 2, 3 and 5, the effect of phytase was significant for AMEN, with the high dose increasing the AMEN. During week 2, AMEN was increased with emulsifier addition. During weeks 1, 2, 3 and 5, birds fed on soy oil-based diets had higher fat retention compared with those fed on tallow-based diets. The high dose of phytase improved the retention of fat during week 5 and the addition of emulsifier resulted in higher fat retention during week 1. During weeks 2, 3 and 5, an interaction between fat source × phytase × emulsifier was observed for N retention. In soy oil-based diets, emulsifier plus 1000 FTU/kg phytase increased N retention compared with other groups, while in tallow-based diets, emulsifier addition increased N retention in diets with 500 FTU/kg, but not in 1000 FTU/kg diet. Overall, the present data suggest that the dietary fat source influenced performance, AMEN and fat retention in broiler chickens. There is opportunity to improve bird performance during d 1-21, AMEN and fat retention with higher doses of microbial phytase. Addition of the emulsifier increased the AMEN during week 2 and tract retention of fat during week 1, but this effect was not translated into improvements in performance.

Effect of a single dose of emulsified versus capsular fish oils on plasma phospholipid fatty acids over 48 hours

USDA-ARS?s Scientific Manuscript database

Emulsified fish oil supplements provide an alternative to encapsulated fish oils. Oil-in-water emulsions may offer an advantage in digestion and absorption thereby increasing the bioavailability of fatty acids. We evaluated the effect of three oil-in-water emulsified fish oils (Emulsion B, Emulsion ...

21 CFR 172.836 - Polysorbate 60.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the weight of the cake icing or cake filling. (6) To impart greater opacity to sugar-type confection... finished sugar coating. (7) As an emulsifier in nonstandardized dressings whereby the maximum amount of the... cream in beverage coffee, with or without one or a combination of the following: (i) Polysorbate 65. (ii...

Saving energy and reducing emissions of both polycyclic aromatic hydrocarbons and particulate matter by adding bio-solution to emulsified diesel.

PubMed

Lin, Yuan-Chung; Lee, Wen-Jhy; Chen, Chun-Chi; Chen, Chung-Bang

2006-09-01

Development of emulsified diesel has been driven by the need to reduce emissions from diesel engines and to save energy. Emulsification technology and bio-solution (NOE-7F) were used to produce emulsified diesel in this study. The experimental results indicated that there were no significant separation layers in W13 (13 wt % water + 87 wt % PDF), W16 (16 wt % water + 84 wt % PDF), W19 (19 wt % water + 81 wt % PDF), E13 (13 wt % NOE-7F water + 87 wt % PDF), E16 (16 wt % NOE-7F water + 83 wt % PDF), and E19 (19 wt % NOE-7F water + 81 wt % PDF) after premium diesel fuel (PDF) was emulsified for more than 30 days. In addition, there was no significant increase in damage from using these six emulsified fuels after the operation of the diesel generator for more than one year. The energy saving and reduction of particulate matter (PM) and total polycyclic aromatic hydrocarbons (PAHs) for W13, W16, W19, E13, E16 and E19, respectively, were 3.90%, 30.9%, 27.6%; 3.38%, 37.0%, 34.9%; 2.17%, 22.2%, 15.4%; 5.87%, 38.6%, 49.3%; 5.88%, 57.8%, 58.0%; and 4.75%, 31.1%, 47.3%, compared with PDF. The above results revealed that the bio-solution (NOE-7F) had a catalytic effect which elevated the combustion efficiency and decreased pollutant emissions during the combustion process. Furthermore, bio-solution (NOE-7F) can stabilize the emulsified fuels and enhance energy saving. Thus, emulsified fuels are highly suitable for use as alternative fuels. Due to the increasing price of diesel, emulsified diesel containing NOE-7F has potential for commercial application.

Application of nanoscale zero valent iron (NZVI) for groundwater remediation in Europe.

PubMed

Mueller, Nicole C; Braun, Jürgen; Bruns, Johannes; Černík, Miroslav; Rissing, Peter; Rickerby, David; Nowack, Bernd

2012-02-01

Nanoscale zero valent iron (NZVI) is emerging as a new option for the treatment of contaminated soil and groundwater targeting mainly chlorinated organic contaminants (e.g., solvents, pesticides) and inorganic anions or metals. The purpose of this article is to give a short overview of the practical experience with NZVI applications in Europe and to present a comparison to the situation in the USA. Furthermore, the reasons for the difference in technology use are discussed. The results in this article are based on an extensive literature review and structured discussions in an expert workshop with experts from Europe and the USA. The evaluation of the experiences was based on a SWOT (strength, weakness, opportunity, threat) analysis. There are significant differences in the extent and type of technology used between NZVI applications in Europe and the USA. In Europe, only three full-scale remediations with NZVI have been carried out so far, while NZVI is an established treatment method in the USA. Bimetallic particles and emulsified NZVI, which are extensively used in the USA, have not yet been applied in Europe. Economic constraints and the precautionary attitude in Europe raise questions regarding whether NZVI is a cost-effective method for aquifer remediation. Challenges to the commercialization of NZVI include mainly non-technical aspects such as the possibility of a public backlash, the fact that the technology is largely unknown to consultants, governments and site owners as well as the lack of long-term experiences. Despite these concerns, the results of the current field applications with respect to contaminant reduction are promising, and no major adverse impacts on the environment have been reported so far. It is thus expected that these trials will contribute to promoting the technology in Europe.

Potential of L-fucose isolated from Brown Seaweeds as Promising Natural Emulsifier compare to Carboxymethyl Cellulose (CMC)

NASA Astrophysics Data System (ADS)

Al-Baarri, A. N.; Legowo, A. M.; Widayat; Abduh, S. B. M.; Lestari, F. P.; Desnasari, D.; Santoso, I. P. M.

2018-02-01

L-fucose has been understood as sulfated polysaccharides and it could be extracted and fractionated from brown algae. These polysaccharides contains carbohydrate, sulfate, and protein that may be used as emulsifier. This research was aimed to study the emulsification properties of L-fucose through the determination of total dissolved solids (TDS), color CIE L*a*b* and stability of oil-in-water emulsion. As much as 0.5% of high concentrated L-fucose and 0.5% of carboxymethyl cellulose (CMC) were used as emulsifier in a 10% (v/v) oil-in-water (O/W) emulsion. The emulsifier was added to O/W emulsions and then heated at 72°C. Result of stability emulsion and TDS showed that L-fucose was comparable to the CMC but remarkable changed the color of O/W emulsion. Heating process significantly reduced the stability O/W emulsion when L-fucose was applied. As conclusion, L-fucose might be used as natural emulsifier in O/W emulsion but in the low heat treatment of food processing. This study may provide valuable information for utilizing natural emulsifier from abundant resources from nature.

Effectiveness of partially hydrolyzed rice glutelin as a food emulsifier: Comparison to whey protein.

PubMed

Xu, Xingfeng; Zhong, Junzhen; Chen, Jun; Liu, Chengmei; Luo, Liping; Luo, Shunjing; Wu, Lixin; McClements, David Julian

2016-12-15

The emulsifying properties of partially hydrolyzed rice glutelin (H-RG, 2% degree of hydrolysis) were compared to those of whey isolate protein (WPI), a commonly used protein-based emulsifier. The surface load of WPI (1% emulsifier, d32=167.5nm) was 2.8 times lower than that of H-RG (3% emulsifier, d32=159.0nm). Emulsions containing WPI-coated lipid droplets had better stability to pH changes (2-8), NaCl addition (0-500mM) and thermal processing (30-90°C, 0 or 200mM NaCl). Nevertheless, H-RG emulsions were stable over a range of conditions: pH 6-8; NaCl≤200 (pH 7); temperatures≤90°C in the absence of salt (pH 7); and temperatures≤50°C in the presence of 200mM NaCl (pH 7). This study indicates that H-RG may be utilized as a natural emulsifier in the development of label-friendly emulsion-based food products, but that further work is needed to increase the range of applications. Copyright © 2016. Published by Elsevier Ltd.

Self-emulsifying excipient platform for improving technological properties of alginate-hydroxypropylcellulose pellets.

PubMed

Mannina, Paolo; Segale, Lorena; Giovannelli, Lorella; Bonda, Andrea Foglio; Pattarino, Franco

2016-02-29

In this work, alginate, alginate-pectin and alginate-hydroxypropylcellulose pellets were produced by ionotropic gelation and characterized. Ibuprofen was selected as model drug; it was suspended in the polymeric solution in crystalline form or dissolved in a self-emulsifying phase and then dispersed into the polymeric solution. The self-emulsifying excipient platform composed of Labrasol (PEG-8 caprylic/capric glycerides) and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS), able to solubilize the drug was used to improve the technological and biopharmaceutical properties of the alginate pellets. The pellets had diameters between 1317 and 2026 μm and a high drug content (>51%). DSC analysis showed the amorphous state of drug in the pellets containing the self-emulsifying phase. All the systems restricted drug release in conditions simulating the gastric environment and made the drug completely available at a pH value typical for the intestine. Only alginate-HPC systems containing the drug solubilized into the self-emulsifying phase showed the ability to partially control the release of ibuprofen at neutral pH. The self-emulsifying excipient platform is a useful tool to improve technological and biopharmaceutical properties of alginate-HPC pellets. Copyright © 2015 Elsevier B.V. All rights reserved.

Selective factors governing in vitro β-carotene bioaccessibility: negative influence of low filtration cutoffs and alterations by emulsifiers and food matrices.

PubMed

Corte-Real, Joana; Richling, Elke; Hoffmann, Lucien; Bohn, Torsten

2014-12-01

Because of their putative health benefits, the biological fate of carotenoids after digestion has been met with much interest, and ex vivo methods using carotenoid standards to study their digestion and further metabolism have been developed. In the absence of a complex food matrix, that is, when studying isolated carotenoids, protocol conditions of gastrointestinal digestion models have to be adjusted. In this investigation, we hypothesized that certain selected factors would significantly influence the bioaccessibility of β-carotene in vitro. The factors considered included (i) type of lipid matrix employed (milk, cream, or oil), (ii) presence/absence of emulsifiers (e.g. lecithin and taurocholate), (iii) addition of a gastric lipase, and (iv) final filtration (20 or 200 nm) of the digesta. Adding an emulsifier mixture (10 mg lecithin + 50 mg monoolein + 5 mg oleic acid) enhanced β-carotene bioaccessibility 3 times (P < 0.001), whereas additional taurocholate and the presence/absence of gastric lipase added before intestinal digestion had no significant effect. β-Carotene bioaccessibility was superior with oil than with milk (18.8% ± 0.7% and 6.1% ± 0.7%, respectively; P = 0.03), especially after filtration, thus suggesting incomplete micelle formation after addition of milk. Filtration through 20 nm filters reduced carotenoid concentration in the aqueous fraction (from 7.1% ± 0.2% to 5.5% ± 0.2% in samples digested with canola oil, P < 0.001), indicating that not all formed micelles compared in size with those normally formed in vivo. When studying carotenoid standards during in vitro digestion, care should be taken to separate mixed micelles by filtration, and the choice of emulsifier and matrix should be considered. Copyright © 2014 Elsevier Inc. All rights reserved.

Efficiency of emulsifier-free emulsions and emulsions containing rapeseed lecithin as delivery systems for vectorization and release of coenzyme Q10: physico-chemical properties and in vitro evaluation.

PubMed

Kaci, M; Arab-Tehrany, E; Dostert, G; Desjardins, I; Velot, E; Desobry, S

2016-11-01

To improve the encapsulation and release of coenzyme Q10 (CoQ10), emulsifier-free-emulsions were developed with a new emulsification process using high-frequency ultrasound (HFU) at 1.7MHz. Nano-emulsions containing CoQ10 were prepared with or without rapeseed lecithin as an emulsifier. The emulsions prepared with HFU were compared with an emulsion of CoQ10 containing emulsifier prepared with the same emulsification technique as well as with emulsions prepared with low-frequency ultrasound coupled with high-pressure homogenization (LFU+HPH). The physico-chemical properties of the emulsions were determined by average droplet size measurement with nano-droplet tracking analysis, droplet surface charge with ζ potential measurement, surface tension and rheological behaviour. Emulsions made by LFU+HPH with an emulsifier showed lower droplet sizes due to cavitation generated by the HFU process. Surface tension results showed that there was no significant difference between emulsions containing lecithin emulsifier regardless of the preparation process or the inclusion of CoQ10. In vitro biocompatibility tests were performed on human mesenchymal stem cells in order to show the cytotoxicity of various formulations and the efficiency of CoQ10-loaded emulsions. In vitro tests proved that the vectors were not toxic. Furthermore, CoQ10 facilitated a high rate of cell proliferation and metabolic activity especially when in an emulsifier-free formulation. Copyright © 2016 Elsevier B.V. All rights reserved.

Biotechnology of siderophores in high-impact scientific fields.

PubMed

De Serrano, Luis O

2017-09-26

Different aspects of bacterial and fungal siderophore biotechnological applications will be discussed. Areas of application presented include, but are not limited to agriculture, medicine, pharmacology, bioremediation, biodegradation and food industry. In agriculture-related applications, siderophores could be employed to enhance plant growth due to their uptake by rhizobia. Siderophores hindered the presence of plant pathogens in biocontrol strategies. Bioremediation studies on siderophores discuss mostly the mobilization of heavy metals and radionuclides; the emulsifying effects of siderophore-producing microorganisms in oil-contaminated environments are also presented. The different applications found in literature based in medicine and pharmacological approaches range from iron overload to drug delivery systems and, more recently, vaccines. Additional research should be done in siderophore production and their metabolic relevance to have a deeper understanding for future biotechnological advances.

Retention and release of oil-in-water emulsions from filled hydrogel beads composed of calcium alginate: impact of emulsifier type and pH.

PubMed

Zeeb, Benjamin; Saberi, Amir Hossein; Weiss, Jochen; McClements, David Julian

2015-03-21

Delivery systems based on filled hydrogel particles (microgels) can be fabricated from natural food-grade lipids and biopolymers. The potential for controlling release characteristics by modulating the electrostatic interactions between emulsifier-coated lipid droplets and the biopolymer matrix within hydrogel particles was investigated. A multistage procedure was used to fabricate calcium alginate beads filled with lipid droplets stabilized by non-ionic, cationic, anionic, or zwitterionic emulsifiers. Oil-in-water emulsions stabilized by Tween 60, DTAB, SDS, or whey protein were prepared by microfluidization, mixed with various alginate solutions, and then microgels were formed by simple extrusion into calcium solutions. The microgels were placed into a series of buffer solutions with different pH values (2 to 11). Lipid droplets remained encapsulated under acidic and neutral conditions, but were released under highly basic conditions (pH 11) due to hydrogel swelling when the alginate concentration was sufficiently high. Lipid droplet release increased with decreasing alginate concentration, which could be attributed to an increase in the pore size of the hydrogel matrix. These results have important implications for the design of delivery systems to entrap and control the release of lipophilic bioactive components within filled hydrogel particles.

Preparation and impact of multiple (water-in-oil-in-water) emulsions in meat systems.

PubMed

Cofrades, S; Antoniou, I; Solas, M T; Herrero, A M; Jiménez-Colmenero, F

2013-11-01

The aim of this paper was to prepare and characterise multiple emulsions and assess their utility as pork backfat replacers in meat gel/emulsion model systems. In order to improve the fat content (in quantitative and qualitative terms) pork backfat was replaced by a water-in-oil-in-water emulsion (W1/O/W2) prepared with olive oil (as lipid phase), polyglycerol ester of polyricinoleic acid (PGPR) as a lipophilic emulsifier, and sodium caseinate (SC) and whey protein concentrate (WP) as hydrophilic emulsifiers. The emulsion properties (particle size and distribution, stability, microstructure) and meat model system characteristics (composition, texture, fat and water binding properties, and colour) of the W1/O/W2, as affected by reformulation, were evaluated. Multiple emulsions showed a well-defined monomodal distribution. Freshly prepared multiple emulsions showed good thermal stability (better using SC) with no creaming. The meat systems had good water and fat binding properties irrespective of formulation. The effect on texture by replacement of pork backfat by W1/O/W2 emulsions generally depends on the type of double emulsion (associated with the hydrophilic emulsifier used in its formulation) and the fat level in the meat system. Copyright © 2013 Elsevier Ltd. All rights reserved.

Studies on the development of latent fingerprints by the method of solid-medium ninhydrin.

PubMed

Yang, Ruiqin; Lian, Jie

2014-09-01

A new series of fingerprint developing membrane were prepared using ninhydrin as the developing agent, and pressure-sensitive emulsifiers as the encapsulated chemicals. The type of emulsifier, plastic film, concentration of the developing agent, modifying ions and thickness of the membrane were studied in order to get the optimized fingerprint developing effect. The membrane can be successfully applied to both latent sweat fingerprints and blood fingerprint on many different surfaces. The sensitivity of the method toward the latent sweat fingerprint is 0.1 mg/L amino acid. The membrane can be applied to both porous and non-porous surfaces. Fingerprints that are difficult to develop on surfaces such as leather, glass and heat-sensitive paper using traditional chemical methods can be successfully developed with this membrane. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Antioxidant activity of alkyl gallates and glycosyl alkyl gallates in fish oil in water emulsions: relevance of their surface active properties and of the type of emulsifier.

PubMed

González, María J; Medina, Isabel; Maldonado, Olivia S; Lucas, Ricardo; Morales, Juan C

2015-09-15

The antioxidant activity of gallic acid and a series of alkyl gallates (C4-C18) and glycosylated alkyl gallates (C4-C18) on fish oil-in-water emulsions was studied. Three types of emulsifiers, lecithin, Tween-20 and sodium dodecyl sulphate (SDS) were tested. A nonlinear behavior of the antioxidant activity of alkyl gallates when increasing alkyl chain length was observed for emulsions prepared with lecithin. Medium-size alkyl gallates (C6-C12) were the best antioxidants. In contrast, for emulsions prepared with Tween-20, the antioxidants seem to follow the polar paradox. Glucosyl alkyl gallates were shown previously to be better surfactants than alkyl gallates. Nevertheless, they exhibited a worse antioxidant capacity than their corresponding alkyl gallates, in emulsions prepared with lecithin or Tween-20, indicating the greater relevance of having three OH groups at the polar head in comparison with having improved surfactant properties but just a di-ortho phenolic structure in the antioxidant. Copyright © 2015 Elsevier Ltd. All rights reserved.

Formation and stabilization of nanoemulsion-based vitamin E delivery systems using natural biopolymers: Whey protein isolate and gum arabic.

PubMed

Ozturk, Bengu; Argin, Sanem; Ozilgen, Mustafa; McClements, David Julian

2015-12-01

Natural biopolymers, whey protein isolate (WPI) and gum arabic (GA), were used to fabricate emulsion-based delivery systems for vitamin E-acetate. Stable delivery systems could be formed when vitamin E-acetate was mixed with sufficient orange oil prior to high pressure homogenization. WPI (d32=0.11 μm, 1% emulsifier) was better than GA (d32=0.38 μm, 10% emulsifier) at producing small droplets at low emulsifier concentrations. However, WPI-stabilized nanoemulsions were unstable to flocculation near the protein isoelectric point (pH 5.0), at high ionic strength (>100mM), and at elevated temperatures (>60 °C), whereas GA-stabilized emulsions were stable. This difference was attributed to differences in emulsifier stabilization mechanisms: WPI by electrostatic repulsion; GA by steric repulsion. These results provide useful information about the emulsifying and stabilizing capacities of natural biopolymers for forming food-grade vitamin-enriched delivery systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of high hydrostatic pressure on secondary structure and emulsifying behavior of sweet potato protein

NASA Astrophysics Data System (ADS)

Mehmood Khan, Nasir; Mu, Tai-Hua; Sun, Hong-Nan; Zhang, Miao; Chen, Jing-Wang

2015-04-01

In this study, secondary structures of sweet potato protein (SPP) after high hydrostatic pressure (HHP) treatment (200-600 MPa) were evaluated and emulsifying properties of emulsions with HHP-treated SPP solutions in different pH values (3, 6, and 9) were investigated. Circular dichroism analysis confirmed the modification of the SPP secondary structure. Surface hydrophobicity increased at pH 3 and decreased at 6 and 9. Emulsifying activity index at pH 6 increased with an increase in pressure, whereas emulsifying stability index increased at pH 6 and 9. Oil droplet sizes decreased, while volume frequency distribution of the smaller droplets increased at pH 3 and 6 with the HHP treatment. Emulsion viscosity increased at pH 6 and 9 and pseudo-plastic flow behaviors were not altered for all emulsions produced with HHP-treated SPP. These results suggested that HHP could modify the SPP structure for better emulsifying properties, which could increase the use of SPP emulsion in the food industry.

Comparison of subarachnoid anesthetic effect of emulsified volatile anesthetics in rats.

PubMed

Guo, Jiao; Zhou, Cheng; Liang, Peng; Huang, Han; Li, Fengshan; Chen, Xiangdong; Liu, Jin

2014-01-01

Spinal cord is an important target of volatile anesthetics in particular for the effect of immobility. Intrathecal injection of volatile anesthetics has been found to produce subarachnoid anesthesia. The present study was designed to compare spinal anesthetic effects of emulsified volatile anesthetics, and to investigate the correlation between their spinal effects and general effect of immobility. In this study, halothane, isoflurane, enflurane and sevoflurane were emulsified by 30% Intralipid. These emulsified volatile anesthetics were intravenously and intrathecally injected, respectively. ED50 of general anesthesia and EC50 of spinal anesthesia were determined. The durations of general and spinal anesthesia were recorded. Correlation analysis was applied to evaluate the anesthetic potency of volatile anesthetics between their spinal and general effects. ED50 of general anesthesia induced by emulsified halothane, isoflurane, enflurane and sevoflurane were 0.41 ± 0.07, 0.54 ± 0.07, 0.74 ± 0.11 and 0.78 ± 0.08 mmol/kg, respectively, with significant correlation to their inhaled MAC (R(2) = 0.8620, P = 0.047). For intrathecal injection, EC50 of spinal anesthesia induced by emulsified halothane, isoflurane, enflurane and sevoflurane were 0.35, 0.27, 0.33 and 0.26 mol/L, respectively, which could be predicted by the product of inhaled MAC and olive oil/gas partition coefficients (R(2) = 0.9627, P = 0.013). In conclusion, potency and efficacy of the four emulsified volatile anesthetics in spinal anesthesia were similar and could be predicted by the product of inhaled MAC and olive oil/gas partition coefficients (MAC × olive oil/gas partition coefficients).

Comparison of subarachnoid anesthetic effect of emulsified volatile anesthetics in rats

PubMed Central

Guo, Jiao; Zhou, Cheng; Liang, Peng; Huang, Han; Li, Fengshan; Chen, Xiangdong; Liu, Jin

2014-01-01

Spinal cord is an important target of volatile anesthetics in particular for the effect of immobility. Intrathecal injection of volatile anesthetics has been found to produce subarachnoid anesthesia. The present study was designed to compare spinal anesthetic effects of emulsified volatile anesthetics, and to investigate the correlation between their spinal effects and general effect of immobility. In this study, halothane, isoflurane, enflurane and sevoflurane were emulsified by 30% Intralipid. These emulsified volatile anesthetics were intravenously and intrathecally injected, respectively. ED50 of general anesthesia and EC50 of spinal anesthesia were determined. The durations of general and spinal anesthesia were recorded. Correlation analysis was applied to evaluate the anesthetic potency of volatile anesthetics between their spinal and general effects. ED50 of general anesthesia induced by emulsified halothane, isoflurane, enflurane and sevoflurane were 0.41 ± 0.07, 0.54 ± 0.07, 0.74 ± 0.11 and 0.78 ± 0.08 mmol/kg, respectively, with significant correlation to their inhaled MAC (R2 = 0.8620, P = 0.047). For intrathecal injection, EC50 of spinal anesthesia induced by emulsified halothane, isoflurane, enflurane and sevoflurane were 0.35, 0.27, 0.33 and 0.26 mol/L, respectively, which could be predicted by the product of inhaled MAC and olive oil/gas partition coefficients (R2 = 0.9627, P = 0.013). In conclusion, potency and efficacy of the four emulsified volatile anesthetics in spinal anesthesia were similar and could be predicted by the product of inhaled MAC and olive oil/gas partition coefficients (MAC × olive oil/gas partition coefficients). PMID:25674241

Application of D-optimal experimental design method to optimize the formulation of O/W cosmetic emulsions.

PubMed

Djuris, J; Vasiljevic, D; Jokic, S; Ibric, S

2014-02-01

This study investigates the application of D-optimal mixture experimental design in optimization of O/W cosmetic emulsions. Cetearyl glucoside was used as a natural, biodegradable non-ionic emulsifier in the relatively low concentration (1%), and the mixture of co-emulsifiers (stearic acid, cetyl alcohol, stearyl alcohol and glyceryl stearate) was used to stabilize the formulations. To determine the optimal composition of co-emulsifiers mixture, D-optimal mixture experimental design was used. Prepared emulsions were characterized with rheological measurements, centrifugation test, specific conductivity and pH value measurements. All prepared samples appeared as white and homogenous creams, except for one homogenous and viscous lotion co-stabilized by stearic acid alone. Centrifugation testing revealed some phase separation only in the case of sample co-stabilized using glyceryl stearate alone. The obtained pH values indicated that all samples expressed mild acid value acceptable for cosmetic preparations. Specific conductivity values are attributed to the multiple phases O/W emulsions with high percentages of fixed water. Results of the rheological measurements have shown that the investigated samples exhibited non-Newtonian thixotropic behaviour. To determine the influence of each of the co-emulsifiers on emulsions properties, the obtained results were evaluated by the means of statistical analysis (ANOVA test). On the basis of comparison of statistical parameters for each of the studied responses, mixture reduced quadratic model was selected over the linear model implying that interactions between co-emulsifiers play the significant role in overall influence of co-emulsifiers on emulsions properties. Glyceryl stearate was found to be the dominant co-emulsifier affecting emulsions properties. Interactions between the glyceryl stearate and other co-emulsifiers were also found to significantly influence emulsions properties. These findings are especially important as they can be used for development of the product that meets users' requirements, as represented in the study. © 2013 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Approach for energy saving and pollution reducing by fueling diesel engines with emulsified biosolution/ biodiesel/diesel blends.

PubMed

Lin, Yuan-Chung; Lee, Wen-Jhy; Chao, How-Ran; Wang, Shu-Li; Tsou, Tsui-Chun; Chang-Chien, Guo-Ping; Tsai, Perng-Jy

2008-05-15

The developments of both biodiesel and emulsified diesel are being driven by the need for reducing emissions from diesel engines and saving energy. Artificial chemical additives are also being used in diesel engines for increasing their combustion efficiencies. But the effects associated with the use of emulsified additive/biodiesel/diesel blends in diesel engines have never been assessed. In this research, the premium diesel fuel (PDF) was used as the reference fuel. A soy-biodiesel was selected as the test biodiesel. A biosolution made of 96.5 wt % natural organic enzyme-7F (NOE-7F) and 3.5 wt % water (NOE-7F water) was used as the fuel additive. By adding additional 1 vol % of surfactant into the fuel blend, a nanotechnology was used to form emulsified biosolution/soy-biodiesel/PDF blends for fueling the diesel engine. We found that the emulsified biosolution/soy-biodiesel/PDF blends did not separate after being kept motionless for 30 days. The above stability suggests that the above combinations are suitable for diesel engines as alternative fuels. Particularly, we found that the emulsified biosolution/soy-biodiesel/PDF blends did have the advantage in saving energy and reducing the emissions of both particulate matters (PM) and polycyclic aromatic hydrocarbons (PAHs) from diesel engines as compared with PDF, soy-biodiesel/PDF blends, and emulsified soy-biodiesel/ PDF blends. The results obtained from this study will provide useful approaches for reducing the petroleum reliance, pollution, and global warming. However, it should be noted that NO(x) emissions were not measured in the present study which warrants the need for future investigation.

Enteral Formula Containing Egg Yolk Lecithin Improves Diarrhea.

PubMed

Akashi, Tetsuro; Muto, Ayano; Takahashi, Yayoi; Nishiyama, Hiroshi

2017-09-01

Diarrhea often occurs during enteral nutrition. Recently, several reports showed that diarrhea improves by adding egg yolk lecithin, an emulsifier, in an enteral formula. Therefore, we evaluated if this combination could improve diarrhea outcomes. We retrospectively investigated the inhibitory effects on watery stools by replacing a polymeric fomula with that containing egg yolk lecithin. Then, we investigated the emulsion stability in vitro. Next, we examined the lipid absorption using different emulsifiers among bile duct-ligated rats and assessed whether egg yolk lecithin, medium-chain triglyceride, and dietary fiber can improve diarrhea outcomes in a rat model of short bowel syndrome. Stool consistency or frequency improved on the day after using the aforementioned combination in 13/14 patients. Average particle size of the egg yolk lecithin emulsifier did not change by adding artificial gastric juice, whereas that of soy lecithin and synthetic emulsifiers increased. Serum triglyceride concentrations were significantly higher in the egg yolk lecithin group compared with the soybean lecithin and synthetic emulsifier groups in bile duct-ligated rats. In rats with short bowels, the fecal consistency was a significant looser the dietary fiber (+) group than the egg yolk lecithin (+) groups from day 6 of test meal feedings. The fecal consistency was also a significant looser the egg yolk lecithin (-) group than the egg yolk lecithin (+) groups from day 4 of test meal feeding. The fecal consistency was no significant difference between the medium-chain triglycerides (-) and egg yolk lecithin (+) groups. Enteral formula emulsified with egg yolk lecithin promotes lipid absorption by preventing the destruction of emulsified substances by gastric acid. This enteral formula improved diarrhea and should reduce the burden on patients and healthcare workers.

Stabilizing effect of cetostearyl alcohol and glyceryl monostearate as co-emulsifiers on hydrocarbon-free O/W glyceride creams.

PubMed

Ballmann, C; Mueller, B W

2008-01-01

The structure of a stable O/W cream is characterized by a more or less pronounced mixed crystal bilayer. The addition of co-emulsifiers in order to achieve a soft formulation often leads to a mixed crystal bilayer network of high viscosity and even phase separation. In order to ovoid this components of different chemical identities are used which often are not inert or harmless if they are absorbed. For this reason it seems to be interesting to use only components from one chemical family, e.g. to use only glycerides and their derivatives because in the case of absorption they are metabolized. The disadvantages of glyceride creams are, however, their low viscosity. The aim of this investigation was to find the optimum amount of co-emulsifier as consistency excipient for the basic formulation of an O/W glyceride cream. This was achieved by using differential scanning calorimetry; thermogravimetry, oscillation rheology and various stress tests. The amount of co-emulsifier used should not be too high, as it would crystallize increasingly during storage which gives the preparation an optical inhomogenity and a lack in softness which is needed for a suitable cosmetic acceptance. A slightly higher concentration than is necessary for the mixed emulsifier system can be advantageous, as the formation of a separate crystalline lipophilic network in the preparation increases its viscosity which will lead to a higher physico-chemical stability of the formulation. These results were obtained with the co-emulsifiers glyceryl monostearate (Imwitor 900), cetylstearyl alcohol (Lanette O), and PEG-20-glycerolstearate (Tagat S2) as O/W emulsifier. As oil phase a mixture of Miglyol 812 (caprylic/capric triglyceride) and Avocado oil was used.

Surface phase behavior and microstructure of lipid/PEG-emulsifier monolayer-coated microbubbles.

PubMed

Borden, Mark A; Pu, Gang; Runner, Gabriel J; Longo, Marjorie L

2004-06-01

Langmuir trough methods and fluorescence microscopy were combined to investigate the phase behavior and microstructure of monolayer shells coating micron-scale bubbles (microbubbles) typically used in biomedical applications. The monolayer shell consisted of a homologous series of saturated acyl chain phospholipids and an emulsifier containing a single hydrophobic stearate chain and polyethylene glycol (PEG) head group. PEG-emulsifier was fully miscible with expanded phase lipids and phase separated from condensed phase lipids. Phase coexistence was observed in the form of dark condensed phase lipid domains surrounded by a sea of bright, emulsifier-rich expanded phase. A rich assortment of condensed phase area fractions and domain morphologies, including networks and other novel structures, were observed in each batch of microbubbles. Network domains were reproduced in Langmuir monolayers under conditions of heating-cooling followed by compression-expansion, as well as in microbubble shells that underwent surface flow with slight compression. Domain size decreased with increased cooling rate through the phase transition temperature, and domain branching increased with lipid acyl chain length at high cooling rates. Squeeze-out of the emulsifier at a surface pressure near 35 mN/m was indicated by a plateau in Langmuir isotherms and directly visualized with fluorescence microscopy, although collapse of the solid lipid domains occurred at much higher surface pressures. Compression of the monolayer past the PEG-emulsifier squeeze-out surface pressure resulted in a dark shell composed entirely of lipid. Under certain conditions, the PEG-emulsifier was reincorporated upon subsequent expansion. Factors that affect shell formation and evolution, as well as implications for the rational design of microbubbles in medical applications, are discussed.

Formulation Strategies to Improve the Bioavailability of Poorly Absorbed Drugs with Special Emphasis on Self-Emulsifying Systems

PubMed Central

Gupta, Shweta; Kesarla, Rajesh

2013-01-01

Poorly water-soluble drug candidates are becoming more prevalent. It has been estimated that approximately 60–70% of the drug molecules are insufficiently soluble in aqueous media and/or have very low permeability to allow for their adequate and reproducible absorption from the gastrointestinal tract (GIT) following oral administration. Formulation scientists have to adopt various strategies to enhance their absorption. Lipidic formulations are found to be a promising approach to combat the challenges. In this review article, potential advantages and drawbacks of various conventional techniques and the newer approaches specifically the self-emulsifying systems are discussed. Various components of the self-emulsifying systems and their selection criteria are critically reviewed. The attempts of various scientists to transform the liquid self-emulsifying drug delivery systems (SEDDS) to solid-SEDDS by adsorption, spray drying, lyophilization, melt granulation, extrusion, and so forth to formulate various dosage forms like self emulsifying capsules, tablets, controlled release pellets, beads, microspheres, nanoparticles, suppositories, implants, and so forth have also been included. Formulation of SEDDS is a potential strategy to deliver new drug molecules with enhanced bioavailability mostly exhibiting poor aqueous solubility. The self-emulsifying system offers various advantages over other drug delivery systems having potential to solve various problems associated with drugs of all the classes of biopharmaceutical classification system (BCS). PMID:24459591

Effect of Grape Seed Proanthocyanidin-Gelatin Colloidal Complexes on Stability and in Vitro Digestion of Fish Oil Emulsions.

PubMed

Su, Yu-Ru; Tsai, Yi-Chin; Hsu, Chun-Hua; Chao, An-Chong; Lin, Cheng-Wei; Tsai, Min-Lang; Mi, Fwu-Long

2015-11-25

The colloidal complexes composed of grape seed proanthocyanidin (GSP) and gelatin (GLT), as natural antioxidants to improve stability and inhibit lipid oxidation in menhaden fish oil emulsions, were evaluated. The interactions between GSP and GLT, and the chemical structures of GSP/GLT self-assembled colloidal complexes, were characterized by isothermal titration calorimetry (ITC), circular dichroism (CD), and Fourier transform infrared spectroscopic (FTIR) studies. Fish oil was emulsified with GLT to obtain an oil-in-water (o/w) emulsion. After formation of the emulsion, GLT was fixed by GSP to obtain the GSP/GLT colloidal complexes stabilized fish oil emulsion. Menhaden oil emulsified by GSP/GLT(0.4 wt %) colloidal complexes yielded an emulsion with smaller particles and higher emulsion stability as compared to its GLT emulsified counterpart. The GSP/GLT colloidal complexes inhibited the lipid oxidation in fish oil emulsions more effectively than free GLT because the emulsified fish oil was surrounded by the antioxidant GSP/GLT colloidal complexes. The digestion rate of the fish oil emulsified with the GSP/GLT colloidal complexes was reduced as compared to that emulsified with free GLT. The extent of free fatty acids released from the GSP/GLT complexes stabilized fish oil emulsions was 63.3% under simulated digestion condition, indicating that the fish oil emulsion was considerably hydrolyzed with lipase.

Emulsified systems based on glyceryl monostearate and potassium cetyl phosphate: scale-up and characterization of physical properties.

PubMed

Baby, André Rolim; Santoro, Diego Monegatto; Velasco, Maria Valéria Robles; Dos Reis Serra, Cristina Helena

2008-09-01

Introducing a pharmaceutical product on the market involves several stages of research. The scale-up stage comprises the integration of previous phases of development and their integration. This phase is extremely important since many process limitations which do not appear on the small scale become significant on the transposition to a large one. Since scientific literature presents only a few reports about the characterization of emulsified systems involving their scaling-up, this research work aimed at evaluating physical properties of non-ionic and anionic emulsions during their manufacturing phases: laboratory stage and scale-up. Prototype non-ionic (glyceryl monostearate) and anionic (potassium cetyl phosphate) emulsified systems had the physical properties by the determination of the droplet size (D[4,3], mum) and rheology profile. Transposition occurred from a batch of 500-50,000g. Semi-industrial manufacturing involved distinct conditions: intensity of agitation and homogenization. Comparing the non-ionic and anionic systems, it was observed that anionic emulsifiers generated systems with smaller droplet size and higher viscosity in laboratory scale. Besides that, for the concentrations tested, augmentation of the glyceryl monostearate emulsifier content provided formulations with better physical characteristics. For systems with potassium cetyl phosphate, droplet size increased with the elevation of the emulsifier concentration, suggesting inadequate stability. The scale-up provoked more significant alterations on the rheological profile and droplet size on the anionic systems than the non-ionic.

Thermal, emulsifying and rheological properties of polysaccharides sequentially extracted from Vaccinium bracteatum Thunb leaves.

PubMed

Xu, Qi-Xin; Shi, Jun-Jun; Zhang, Jian-Guo; Li, Ling; Jiang, Li; Wei, Zhao-Jun

2016-12-01

Plant polysaccharides are widely used in food industry as thickening and gelling agents and these attributes largely depend on their thermal, emulsifying and rheological properties. As known, the extraction methods always bring about the diversification of property and functions of polysaccharides. Thus, the Vaccinium bracteatum Thunb leaves polysaccharides (VBTLP) were sequentially extracted using hot buffer (HBSS), chelating agent (CHSS), dilute alkaline (DASS) and concentrated alkaline (CASS). The thermal, emulsifying and rheological properties of VBTLP were investigated in the present study. Within the range of 20-225°C, CHSS showed the highest peak temperature, whereas HBSS displayed the highest endothermic enthalpy and highest emulsifying activity, while, CASS showed the longest emulsifying stability. The VBTLP solutions exhibited non-Newtonian shear-thinning behavior within the concentrations of 0.6-2.5%. The apparent viscosity of VBTLP solution decreased under following conditions: acidic pH (4.0), alkaline pH (10.0), in the presence of Ca 2+ and at high temperature, while it increased in the presence of Na + and at freezing conditions. The modulus G' and G″ of VBTLP solutions were increased with increasing oscillation frequency, and the crossover frequency shifted to lower values when the polysaccharide content increased. The above results of thermal, emulsifying and rheological properties of VBTLPs supplied the basis for V. bracteatum leaves in potential industrial applications of foods. Copyright © 2016 Elsevier B.V. All rights reserved.

Influence of different emulsifiers on characteristics of eggless cake containing soy milk: Modeling of physical and sensory properties by mixture experimental design.

PubMed

Rahmati, Nazanin Fatemeh; Mazaheri Tehrani, Mostafa

2014-09-01

Emulsifiers of different structures and functionalities are important ingredients usually used in baking cakes with satisfactory properties. In this study, three emulsifiers including distilled glycerol mono stearate (DGMS), lecithin and sorbitan mono stearate (SMS) were used to bake seven eggless cakes containing soy milk and optimization was performed by using mixture experimental design to produce an eggless cake sample with optimized properties. Physical properties of cake batters (viscosity, specific gravity and stability), cake quality parameters (moisture loss, density, specific volume, volume index, contour, symmetry, color and texture) and sensory attributes of eggless cakes were analyzed to investigate functional potential of the emulsifiers and results were compared with those of control cake containing egg. Almost in all cases emulsifiers, compared to the control cake, changed properties of eggless cakes significantly. Regarding models of different response variables (except for some properties) and their high R(2) (99.51-100), it could be concluded that models obtained by mixture design were significantly fitted for the studied responses.

Interfacial and emulsifying properties of designed β-strand peptides.

PubMed

Dexter, Annette F

2010-12-07

The structural and surfactant properties of a series of amphipathic β-strand peptides have been studied as a function of pH. Each nine-residue peptide has a framework of hydrophobic proline and phenylalanine amino acid residues, alternating with acidic or basic amino acids to give a sequence closely related to known β-sheet formers. Surface activity, interfacial mechanical properties, electronic circular dichroism (ECD), droplet sizing and zeta potential measurements were used to gain an overview of the peptide behavior as the molecular charge varied from ±4 to 0 with pH. ECD data suggest that the peptides form polyproline-type helices in bulk aqueous solution when highly charged, but may fold to β-hairpins rather than β-sheets when uncharged. In the uncharged state, the peptides adsorb readily at a macroscopic fluid interface to form mechanically strong interfacial films, but tend to give large droplet sizes on emulsification, apparently due to flocculation at a low droplet zeta potential. In contrast, highly charged peptide states gave a low interfacial coverage, but retained good emulsifying activity as judged by droplet size. Best emulsification was generally seen for intermediate charged states of the peptides, possibly representing a compromise between droplet zeta potential and interfacial binding affinity. The emulsifying properties of β-strand peptides have not been previously reported. Understanding the interfacial properties of such peptides is important to their potential development as biosurfactants.

Effect of Formulation Variables on Preparation of Celecoxib Loaded Polylactide-Co-Glycolide Nanoparticles

PubMed Central

Cooper, Dustin L.; Harirforoosh, Sam

2014-01-01

Polymer based nanoparticle formulations have been shown to increase drug bioavailability and/or reduce drug adverse effects. Nonsteroidal anti-inflammatory drugs (e.g. celecoxib) reduce prostaglandin synthesis and cause side effects such as gastrointestinal and renal complications. The aim of this study was to formulate celecoxib entrapped poly lactide-co-glycolide based nanoparticles through a solvent evaporation process using didodecyldimethylammonium bromide or poly vinyl alcohol as stabilizer. Nanoparticles were characterized for zeta potential, particle size, entrapment efficiency, and morphology. Effects of stabilizer concentration (0.1, 0.25, 0.5, and 1% w/v), drug amount (5, 10, 15, and 20 mg), and emulsifier (lecithin) on nanoparticle characterization were examined for formula optimization. The use of 0.1, 0.25, and 0.5% w/v didodecyldimethylammonium bromide resulted in a more than 5-fold increase in zeta potential and a more than 1.5-fold increase in entrapment efficiency with a reduction in particle size over 35%, when compared to stabilizer free formulation. Nanoparticle formulations were also highly influenced by emulsifier and drug amount. Using 0.25% w/v didodecyldimethylammonium bromide NP formulations, peak zeta potential was achieved using 15 mg celecoxib with emulsifier (17.15±0.36 mV) and 20 mg celecoxib without emulsifier (25.00±0.18 mV). Peak NP size reduction and entrapment efficiency was achieved using 5 mg celecoxib formulations with (70.87±1.24 nm and 95.55±0.66%, respectively) and without (92.97±0.51 nm and 95.93±0.27%, respectively) emulsifier. In conclusion, formulations using 5 mg celecoxib with 0.25% w/v didodecyldimethylammonium bromide concentrations produced nanoparticles exhibiting enhanced size reduction and entrapment efficiency. Furthermore, emulsifier free formulations demonstrated improved zeta potential when compared to formulations containing emulsifier (p<0.01). Therefore, our results suggest the use of emulsifier free 5 mg celecoxib drug formulations containing 0.25% w/v didodecyldimethylammonium bromide for production of polymeric NPs that demonstrate enhanced zeta potential, small particle size, and high entrapment efficiency. PMID:25502102

Effects of water-emulsified fuel on a diesel engine generator's thermal efficiency and exhaust.

PubMed

Syu, Jin-Yuan; Chang, Yuan-Yi; Tseng, Chao-Heng; Yan, Yeou-Lih; Chang, Yu-Min; Chen, Chih-Chieh; Lin, Wen-Yinn

2014-08-01

Water-emulsified diesel has proven itself as a technically sufficient improvement fuel to improve diesel engine fuel combustion emissions and engine performance. However, it has seldom been used in light-duty diesel engines. Therefore, this paper focuses on an investigation into the thermal efficiency and pollution emission analysis of a light-duty diesel engine generator fueled with different water content emulsified diesel fuels (WD, including WD-0, WD-5, WD-10, and WD-15). In this study, nitric oxide, carbon monoxide, hydrocarbons, and carbon dioxide were analyzed by a vehicle emission gas analyzer and the particle size and number concentration were measured by an electrical low-pressure impactor. In addition, engine loading and fuel consumption were also measured to calculate the thermal efficiency. Measurement results suggested that water-emulsified diesel was useful to improve the thermal efficiency and the exhaust emission of a diesel engine. Obviously, the thermal efficiency was increased about 1.2 to 19.9%. In addition, water-emulsified diesel leads to a significant reduction of nitric oxide emission (less by about 18.3 to 45.4%). However the particle number concentration emission might be increased if the loading of the generator becomes lower than or equal to 1800 W. In addition, exhaust particle size distributions were shifted toward larger particles at high loading. The consequence of this research proposed that the water-emulsified diesel was useful to improve the engine performance and some of exhaust emissions, especially the NO emission reduction. Implications: The accumulated test results provide a good basis to resolve the corresponding pollutants emitted from a light-duty diesel engine generator. By measuring and analyzing transforms of exhaust pollutant from this engine generator, the effects of water-emulsified diesel fuel and loading on emission characteristics might be more clear. Understanding reduction of pollutant emissions during the use of water-emulsified diesel helps improve the effectiveness of the testing program. The analyzed consequences provide useful information to the government for setting policies to curb pollutant emissions from a light-duty diesel engine generator more effectively.

European Scientific Notes. Volume 34, Number 9,

DTIC Science & Technology

1980-09-30

ancient Great Pyramids of Giza . Modern oil/water interfaces by examining their automobiles share the right of way with behavior as emulsifying agents...Cheston 447 The First European Physical Society "Solid State" Meeting J.R. Neighbours 449 Physics, Peace, and Pyramids in Egypt-Part II R.S. Hughes...sputtering with var- ious additives or by introducing PH3 PHYSICS PEACE, AND PYRAMIDS IN EGYPT- ( n type) or BH4 (- p type) into the PART "T SiH, gas used in

Polyfibroblast: A Self-Healing and Galvanic Protection Additive

DTIC Science & Technology

2013-09-25

Specifically we looked at emulsifier (Gum Arabic vs. SiC^), polymer-forming monomer (IPDI vs. BCI ), silane molecular weight (C12 vs. C18 vs. C8-C18...le+6J tu ie+4- le+2 U le+0 ■ Coating ■ Scratch BCI IPDI Isocyanate Type ICoating |Scratch Figure 3: A) Corrosion resistance of the...surprising. The type of monomer also did not appear to matter in these measurements. Whether polymerized from IPDI or BCI , the extent of self-healing

Evaporation control research, 1959-60

USGS Publications Warehouse

,

1963-01-01

Two hundred and forty-five dispersions of long-chain alkanols were formulated by using various emulsifiers and alkanols. The dispensing and spreading ability of each of these formulations was tested. The most promising emulsifier that could be used with any of the alkanols was glyceryl monostearate (self-emulsifying). However, the concentration of the alkanol in the dispersion form varied somewhat: with the length of the carbon chain. A maximum concentration of 16 percent was obtained using the longer chain alkanols in the dispersion form without losing any of the properties of a fluid. Nine field tests were undertaken on small stock tanks. The retardant materials used in these tests were dodecanol, hexadecanol, and octadecanol. These materials were applied in either liquid or dispersion form. Four types of dispensing equipment were tested. The first type used a pressure system which sprayed a liquid onto the surface of the water. An anemometer and wind-controlled vane, operated by an electrical system, determined the length End frequency of application. The second type was similar to the first except that gravity was utilized to force the liquid onto the surface. The third type. used a drip system with rates of about 10 drops per minute. The fourth type used a gravity feed and a wind-controlled valve which allowed the dispersion material to flow onto the surface of the water when the wind was in the proper direction. In the field tests, the best reduction in evaporation was obtained using octadecanol in dispersion form and dispensed with the wind-controlled valve and gravity feed system. The maximum reduction in evaporation for a 2-week period was 27 percent. However, the economics of suppressing evaporation from stock tanks is questionable because of the short travel time across the tank by the film. There are still many problems unsolved. Some of these can be resolved in the laboratory whereas others can be resolved only in the field. Some of the more serious problems are the effect of impurities in the alkanols; the rate of cooling of the alkanol from a liquid to a solid state ; the effect of the film on the exchange of water molecules between the air and water; whether the film remains effective in suppressing evaporation for any rate of movement downwind; and the possible use of dodecanol and eicosanol as suppressants.

Production and partial characterization of bioemulsifier from a chromium-resistant actinobacteria.

PubMed

Colin, Verónica Leticia; Pereira, Claudia Elizabeth; Villegas, Liliana Beatriz; Amoroso, Maria Julia; Abate, Carlos Mauricio

2013-01-01

Surface-active compounds such as synthetic emulsifiers have been used for several decades, both for the degradation of hydrocarbons and increasing desorption of soil-bound metals. However, due to their high toxicity, low degradability, and production costs unaffordable for use in larger ecosystems, synthetic emulsifiers have been gradually replaced by those derived from natural sources such as plants or microbes. In previous studies, the bacterium Streptomyces sp. MC1 has shown the ability to reduce and/or accumulate Cr(VI), a highly promising advance in the development of methods for environmental clean-up of sites contaminated with chromium. Here, new studies on the production of emulsifier from this strain are presented. The cultivation factors that have a significant influence on emulsifier biosynthesis, as well as the interactions among them, were studied by factorial design. Based upon optimization studies, maximum bioemulsifier production was detected in the culture medium having an initial pH of 8 with phosphate 2.0 g L(-1) and Ca(+2) 1.0 g L(-1) added, with an emulsification index about 3.5 times greater compared to the basal value. Interestingly, in the presence of 5.0 g L(-1) Cr(VI), Streptomyces sp. MC1 retained about 65% of its emulsifier production ability. Partially purified emulsifier presented high thermo-stability and partial water solubility. These findings could have promising future prospects for the remediation of organic- and metal-contaminated sites. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Assessment of Red Beet as a Natural Colorant, and Evaluation of Quality Properties of Emulsified Pork Sausage Containing Red Beet Powder during Cold Storage

PubMed Central

Jin, Sang-Keun; Choi, Jung-Seok; Moon, Sung-Sil; Jeong, Jin-Yeon

2014-01-01

The purpose of this study was to assess red beet as a natural colorant in emulsified pork sausage and to investigate the effect of red beet on quality characteristics of emulsified pork sausage during 20 d of cold storage. Red beet was prepared as a powder and a substitute with sodium nitrite at 0.5% and 1.0% levels in emulsified pork sausage. Red beet significantly increased the moisture content and pH (p<0.0001) and affected color traits. Lightness of emulsified pork sausage decreased by the addition of red beet powder (p<0.01), whereas lightness with red beet treatments slightly increased during 20 d of cold storage at 4℃ (p<0.05). Redness dramatically increased with red beet powder (p<0.0001). Color by sensory evaluation also showed a significant effect from red beet addition (p<0.05), whereas the other sensory properties such as flavor, tenderness, juiciness, and overall acceptability were not affected by the addition of red beet powder (p>0.05). Texture and 2-thiobabituric acid reactive substance were also not affected by red beet addition (p>0.05). Therefore, red beet could be a good natural colorant in emulsified pork sausage but it needs additional processing, such as betalain concentration and extraction as a juice, to be used as an antioxidant in meat products. PMID:26761285

Morphological study of polymethyl methacrylate microcapsules filled with self-healing agents

NASA Astrophysics Data System (ADS)

Ahangaran, Fatemeh; Hayaty, Mehran; Navarchian, Amir H.

2017-03-01

Polymethyl methacrylate (PMMA) microcapsules filled with epoxy prepolymer, 3-aminomethyl-3,5,5-trimethylcyclohexylamine, and pentaerythritol tetrakis (3-mercaptopropionate) as healing agents have been prepared separately through internal phase separation method for self-healing purposes. PMMA with two different molecular weights (M bar1 = 36,000 g/mol and M bar2 = 550,000 g/mol) were used with two types of different emulsifiers (ionic and polymeric) to prepare microcapsules. The morphology of healing agent microcapsules was investigated using field emission scanning electron microscopy (FESEM). It was found that PMMA microcapsules separately filled with epoxy and amine had core-shell morphologies with smooth surfaces. The mercaptan/PMMA particles exhibited core-shell and acorn-shape morphologies. The surface morphology of mercaptan microcapsules changed from holed to plain in different emulsion systems. The spreading coefficient (S) of phases in the prepared emulsion systems were calculated from interfacial tension (σ) and contact angle (θ) measurements. The theoretical equilibrium morphology of PMMA microcapsules was predicted according to spreading coefficient values of phases in emulsion systems. It was also found that the surface morphology of PMMA microcapsules depended strongly on the nature of the core, molecular weight of PMMA, type and concentration of emulsifier.

Carbamazepine parenteral nanoemulsions prepared by spontaneous emulsification process.

PubMed

Kelmann, Regina G; Kuminek, Gislaine; Teixeira, Helder F; Koester, Letícia S

2007-09-05

Carbamazepine (CBZ), a widely used anticonvulsant drug, is a poorly soluble drug with no parenteral treatment available for patients. This study was aimed at developing a nanoemulsion for CBZ intravenous delivery. The spontaneous emulsification method was used to prepare different formulations containing 2mg/mL CBZ. Likewise, a 2(2) full factorial experimental design was applied to study the influence of two independent variables (type of oil and type of lipophilic emulsifier) on emulsion physicochemical characteristics. The nanoemulsions were evaluated concerning droplet size, zeta potential, viscosity, drug content and association to oily phase. The formulation, which presented the best characteristics required for intravenous administration was selected and refined with respect to the lipophilic emulsifier content (increase from 5% to 6% of soy lecithin). This formulation was characterized and kept its properties in a satisfactory range over the evaluated period (3 months), i.e. droplet size around 150 nm, drug content around 95% and zeta potential around -40 mV. The transmission electron microscopy revealed emulsion droplets almost spherical in shape with an amorphous core, whereas the in vitro release profile assessed by dialysis bags demonstrated a release kinetics square root time dependent, with 95% of ca. having been released within 11h.

Influence of vitamin E acetate and other lipids on the phase behavior of mesophases based on unsaturated monoglycerides.

PubMed

Sagalowicz, L; Guillot, S; Acquistapace, S; Schmitt, B; Maurer, M; Yaghmur, A; de Campo, L; Rouvet, M; Leser, M; Glatter, O

2013-07-02

The phase behavior of the ternary unsaturated monoglycerides (UMG)-DL-α-tocopheryl acetate-water system has been studied. The effects of lipid composition in both bulk and dispersed lyotropic liquid crystalline phases and microemulsions were investigated. In excess water, progressive addition of DL-α-tocopheryl acetate to a binary UMG mixture results in the following phase sequence: reversed bicontinuous cubic phase, reversed hexagonal (H(II)) phase, and a reversed microemulsion. The action of DL-α-tocopheryl acetate is then compared to that of other lipids such as triolein, limonene, tetradecane, and DL-α-tocopherol. The impact of solubilizing these hydrophobic molecules on the UMG-water phase behavior shows some common features. However, the solubilization of certain molecules, like DL-α-tocopherol, leads to the presence of the reversed micellar cubic phase (space group number 227 and symmetry Fd3m) while the solubilization of others does not. These differences in phase behavior are discussed in terms of physical-chemical characteristics of the added lipid molecule and its interaction with UMG and water. From an applications point of view, phase behavior as a function of the solubilized content of guest molecules (lipid additive in our case) is crucial since macroscopic properties such as molecular release depend strongly on the phase present. The effect of two hydrophilic emulsifiers, used to stabilize the aqueous dispersions of UMG, was studied and compared. Those were Pluronic F127, which is the most commonly used stabilizer for these kinds of inverted type structures, and the partially hydrolyzed emulsifier lecithin (Emultop EP), which is a well accepted food-grade emulsifier. The phase behavior of particles stabilized by the partially hydrolyzed lecithin is similar to that of bulk sample at full hydration, but this emulsifier interacts significantly with the internal structure and affects it much more than F127.

Simulation of in situ uranium bioremediation with slow-release organic amendment injection

NASA Astrophysics Data System (ADS)

Zhang, F.; Parker, J.; Ye, M.; Tang, G.; Wu, W.; Mehlhorn, T.; Gihring, T. M.; Schadt, C.; Watson, D. B.; Brooks, S. C.

2010-12-01

In situ bioremediation of a highly uranium-contaminated gravel aquifer with a slow-release electron donor (emulsified edible oil) has been investigated at the US DOE Oak Ridge Integrated Field Research Challenge (ORIFRC) site in east Tennessee. Groundwater at the study location has pH ~6.7 and contains high concentrations of U (5-6 μM), sulfate (1.0-1.2) mM and Ca (3-4 mM). Diluted emulsified oil (20% solution) was injected into three injection wells within 1.5 hrs. Geochemical analysis of site groundwater demonstrated the sequential reduction of nitrate, Mn, Fe(III) and sulfate. The oil was degraded by indigenous microorganisms with acetate as a major product. Rapid removal of U(VI) from the aqueous phase occurred concurrently with acetate production and sulfate reduction. The field test data were analyzed using a reaction network with a kinetic model for lipid hydrolysis and glycerol fermentation and equilibrium reactions representing microbial reduction of sulfate, nitrate, iron, uranium, manganese and carbon dioxide based on the thermodynamic approach of Istok et al. (2010) using the parallelized HGC5 code. Model-simulated chemical concentrations and relative abundance of functional microbial populations are compared with field measurements. Application of the thermodynamically-based modeling approach instead of the widely used multi-Monod kinetic rate law to formulate bioreduction reactions substantially reduces the number of reaction parameters that need to be calibrated thus facilitating a more comprehensive representation of microbial community dynamics. The model developed through this study is expected to aid the design of future bioremediation strategies for the site.

An investigation into the characteristics and drug release properties of multiple W/O/W emulsion systems containing low concentration of lipophilic polymeric emulsifier.

PubMed

Vasiljevic, Dragana; Parojcic, Jelena; Primorac, Marija; Vuleta, Gordana

2006-02-17

Multiple W/O/W emulsions with high content of inner phase (Phi1=Phi2=0.8) were prepared using relatively low concentrations of lipophilic polymeric primary emulsifier, PEG 30-dipolyhydroxystearate, and diclofenac diethylamine (DDA) as a model drug. The investigated formulations were characterized and their stability over the time was evaluated by dynamic and oscillatory rheological measurements, microscopic analysis and in vitro drug release study. In vitro release profiles of the selected model drug were evaluated in terms of the effective diffusion coefficients and flux of the released drug. The multiple emulsion samples exhibited good stability during the ageing time. Concentration of the lipophilic primary emulsifier markedly affected rheological behaviour as well as the droplet size and in vitro drug release kinetics of the investigated systems. The multiple emulsion systems with highest concentration (2.4%, w/w) of the primary emulsifier had the lowest droplet size and the highest apparent viscosity and highest elastic characteristics. Drug release data indicated predominately diffusional drug release mechanism with sustained and prolonged drug release accomplished with 2.4% (w/w) of lipophilic emulsifier employed.

[The application of the emulsified turpentine baths for the correction of the functional state of the cross-country skiers].

PubMed

Garnov, I O; Kuchin, A V; Loginova, T P; Varlamova, N G; Boiko, E R

2016-01-01

The baths with emulsified turpentine find the wide application in balneotherapy. They produce especially pronounced beneficial prophylactic effects in the patients presenting with microtrombosis and microvascular stasis. Moreover, these baths may be prescribed to improve microcirculation, increase the functional reserves and physical capacity in the athletes. At the same time, the current literature appears to contain no scientific publications on the application of emulsified turpentine baths for the restoration of the physical capacity of the professional ski runners. The lack of relevant information motivated the study reported in the present article. The main objective of the study involving 10 subjects was to evaluate the effectiveness of the modified emulsified turpentine baths as a method by which to restore and enhance the physical capacity of the professional cross-country skiers. The physical capacity of the athletes was evaluated from the results of the bicycle ergometer exercise test with the use of the «Oxycon Pro» system. The data obtained suggest that a course of the emulsified turpentine baths increases the activity of the cardiorespiratory system, improves the physical capacity, and enhances the functional reserves of the body in the anaerobic zone.

Transdermal solid delivery of epigallocatechin-3-gallate using self-double-emulsifying drug delivery system as vehicle: Formulation, evaluation and vesicle-skin interaction.

PubMed

Hu, Caibiao; Gu, Chengyu; Fang, Qiao; Wang, Qiang; Xia, Qiang

2016-02-01

The present study investigated a self-double-emulsifying drug delivery system loaded with epigallocatechin-3-gallate to improve epigallocatechin-3-gallate skin retention. The long chain solid lipids (cetostearyl alcohol) and macadamia oil were utilized as a carrier to deliver the bioactive ingredient. Response surface methodology was used to optimize the formulation, and the solid lipid to total lipid weight ratio, concentration of epigallocatechin-3-gallate and hydrophilic surfactant on skin retention were found to be the principal factors. The optimum formulation with high encapsulation efficiency (95.75%), self-double-emulsification performance (99.58%) and skin retention (87.24%) were derived from the fitted models and experimentally examined, demonstrating a reasonable agreement between experimental and predicted values. Epigallocatechin-3-gallate-self-double-emulsifying drug delivery system was found to be stable for 3 months. Transdermal studies could explain a higher skin diffusion of epigallocatechin-3-gallate from the self-double-emulsifying drug delivery system compared with EGCG aqueous solution. In vitro cytotoxicity showed that epigallocatechin-3-gallate-self-double-emulsifying drug delivery system did not exert hazardous effect on L929 cells up to 1:10. © The Author(s) 2015.

21 CFR 184.1351 - Gum tragacanth.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the following conditions: Maximum Usage Levels Permitted Food (as served) Percent Function Baked goods and baking mixes, § 170.3(n)(1) of this chapter 0.2 Emulsifier and emulsifier salt, § 170.3(o)(8) of...

21 CFR 184.1339 - Guar gum.

Code of Federal Regulations, 2014 CFR

2014-04-01

... the following conditions: Maximum Usage Levels Permitted Food (as served) Percent Function Baked goods and baking mixes, § 170.3(n)(1) of this chapter 0.35 Emulsifier and emulsifier salts, § 170.3(o)(8) of...

Polyamine sensitization in offshore workers handling drilling muds.

PubMed

Ormerod, A D; Wakeel, R A; Mann, T A; Main, R A; Aldridge, R D

1989-11-01

Oil-based mud, a complex mixture containing amines in emulsifiers, is used in offshore drilling operations. It is a skin irritant that occasionally gives rise to allergic contact sensitivity. In patch testing patients with allergy to drilling mud, we have identified polyamine (diethylenetriamine and triethylenetetramine) sensitivity in 5 patients. All 5 patients were also allergic to emulsifiers. These emulsifiers are cross-linked fatty acid amido-amines, in which unreacted amine groups are thought to cross-sensitize with these constituent polyamines. Cross-reactivity between ethylenediamine, diethylenetetramine and triethylenetetramine was found in 9 subjects.

Small particle size lipid emulsions, satiety and energy intake in lean men.

PubMed

Chan, Y K; Budgett, S C; MacGibbon, A K; Quek, S Y; Kindleysides, S; Poppitt, S D

2017-02-01

Lipid emulsions have been proposed to suppress hunger and food intake. Whilst there is no consensus on optimal structural properties or mechanism of action, small particle size (small-PS) stable emulsions may have greatest efficacy. Fabuless®, a commercial lipid emulsion reported in some studies to decrease energy intake (EI), is a small-PS, 'hard' fat emulsion comprising highly saturated palm oil base (PS, 82nm). To determine whether small-PS dairy lipid emulsions can enhance satiety, firstly, we investigated 2 'soft' fat dairy emulsions generated using dairy and soy emulsifying agents (PS, 114nm and 121nm) and a non-emulsified dairy control. Secondly, we investigated a small-PS palmolein based 'hard' fat emulsion (fractionated palm oil, PS, 104nm) and non-emulsified control. This was a 6 arm, randomized, cross-over study in 18 lean men, with test lipids delivered in a breakfast meal: (i) Fabuless® emulsion (F EM ); (ii) dairy emulsion with dairy emulsifier (DE DE ); (iii) dairy emulsion with soy lecithin emulsifier (DE SE ); (iv) dairy control (DC ON ); (v) palmolein emulsion with dairy emulsifier (PE DE ); (vi) palmolein control (PC ON ). Participants rated postprandial appetite sensations using visual analogue scales (VAS), and ad libitum energy intake (EI) was measured at a lunch meal 3.5h later. Dairy lipid emulsions did not significantly alter satiety ratings or change EI relative to dairy control (DE DE , 4035kJ; DE SE , 3904kJ; DC ON , 3985kJ; P>0.05) nor did palm oil based emulsion relative to non-emulsified control (PE DE, 3902 kJ; PC ON, 3973kJ; P>0.05). There was no evidence that small-PS dairy lipid emulsions or commercial Fabuless altered short-term appetite or food intake in lean adults. Copyright © 2016. Published by Elsevier Inc.

Effect of pulsed ultrasound on the physicochemical characteristics and emulsifying properties of squid (Dosidicus gigas) mantle proteins.

PubMed

Higuera-Barraza, O A; Torres-Arreola, W; Ezquerra-Brauer, J M; Cinco-Moroyoqui, F J; Rodríguez Figueroa, J C; Marquez-Ríos, E

2017-09-01

Food technologists are always looking to improve the functional properties of proteins. In this sense, in last years ultrasound has been used to improve some functional properties. For this reason, and considering that jumbo squid is an important fishery in northwest Mexico, the purpose of this research was to determine the effect of pulsed ultrasound on the physicochemical characteristics and emulsifying properties of squid (Dosidicus gigas) mantle proteins. Pulsed ultrasound (20kHz, 20, and 40% amplitude) was applied for 30, 60, and 90s to a protein extract prepared from giant squid mantle causing an increase (p<0.05) in surface hydrophobicity (S o ) from 108.4±1.4 to 239.1±2.4 after application of pulsed ultrasound at 40% of amplitude for 90s. The electrophoretic profile and the total and reactive sulfhydryl contents were not affected (p⩾0.05) by the ultrasound treatment. The emulsifying ability of the protein solution was improved (p<0.05), whereas the Emulsifier Activity Index (EAI) varied from123.67±5.52m 2 /g for the control and increased up to 217.7±3.8m 2 /g after application of the ultrasound. The Stability Emulsifier Index (EEI) was improved at 40% of amplitude by 60 and 90s. The results suggested that pulsed ultrasound used as pretreatment induced conformational changes in giant squid proteins, which improved the interfacial association between protein-oil phases, thus contributing to the improvement of their emulsifient properties. Copyright © 2017 Elsevier B.V. All rights reserved.

The Solid Phase Curing Time Effect of Asbuton with Texapon Emulsifier at the Optimum Bitumen Content

NASA Astrophysics Data System (ADS)

Sarwono, D.; Surya D, R.; Setyawan, A.; Djumari

2017-07-01

Buton asphalt (asbuton) could not be utilized optimally in Indonesia. Asbuton utilization rate was still low because the processed product of asbuton still have impracticable form in the term of use and also requiring high processing costs. This research aimed to obtain asphalt products from asbuton practical for be used through the extraction process and not requiring expensive processing cost. This research was done with experimental method in laboratory. The composition of emulsify asbuton were 5/20 grain, premium, texapon, HCl, and aquades. Solid phase was the mixture asbuton 5/20 grain and premium with 3 minutes mixing time. Liquid phase consisted texapon, HCl and aquades. The aging process was done after solid phase mixing process in order to reaction and tie of solid phase mixed become more optimal for high solubility level of asphalt production. Aging variable time were 30, 60, 90, 120, and 150 minutes. Solid and liquid phase was mixed for emulsify asbuton production, then extracted for 25 minutes. Solubility level of asphalt, water level, and asphalt characteristic was tested at extraction result of emulsify asbuton with most optimum ashphal level. The result of analysis tested data asphalt solubility level at extract asbuton resulted 94.77% on 120 minutes aging variable time. Water level test resulted water content reduction on emulsify asbuton more long time on occurring of aging solid phase. Examination of asphalt characteristic at extraction result of emulsify asbuton with optimum asphalt solubility level, obtain specimen that have rigid and strong texture in order that examination result have not sufficient ductility and penetration value.

In Situ Remediation of Polychlorinated Bephenyls Using Palladium Coated Iron or Magnesium

NASA Technical Reports Server (NTRS)

Geiger, Cherie L.

2003-01-01

The remediation of polychlorinated biphenyls (PCBs) and other chlorinated synthetic aromatic compounds are of great concern due to their toxicity and persistence in the environment. When released into the environment, PCBs are sorbed to particulate matter that can then disperse over large areas. Although the US Environmental Protection Agency (EPA) has banned the manufacture of PCBs since 1979, they are still present in the environment posing possible adverse health affects to both humans and animals. Thus, it is of utmost importance to develop a method that remediates PCB-contaminated soil, sediments, and water. The objective of our research was to develop an in-situ PCB remediation technique that is applicable for the treatment of soils and sediments. Previous research conducted at the University of Central Florida (UCF) proved the feasibility of using an emulsified system to dehalogenate a dense non-aqueous phase liquid (DNAPL) source, such as TCE, in the subsurface by means of an in-situ injection. The generation of a hydrophobic emulsion system drew the DNAPL TCE, through the oil membrane where it diffused to the iron particle and underwent degradation. TCE continued to enter, diffuse, degrade and exit the droplet maintaining a concentration gradient across the membrane, thus maintaining the driving force of the reaction.

Hydrophilic microspheres from water-in-oil emulsions by the water diffusion technique.

PubMed

Trotta, Michele; Chirio, Daniela; Cavalli, Roberta; Peira, Elena

2004-08-01

In this study, we developed and evaluated a novel method to produce insulin-loaded hydrophilic microspheres allowing high encapsulation efficiency and the preservation of peptide stability during particle processing. The preparation method used the diffusion of water by an excess of solvent starting from a water-in-solvent emulsion. The water dispersed phase containing albumin or lactose, or albumin-lactose in different weight ratios, and insulin was emulsified in water-saturated triacetin with and without emulsifiers, producing a water-in-triacetin emulsion. An excess of triacetin was added to the emulsion so that water could be extracted into the continuous phase, allowing the insulin-loaded microsphere precipitation. Insulin stability within the microspheres after processing was evaluated by reverse-phase and size-exclusion high-performance liquid chromatography. The water diffusion extraction process provided spherical microparticles of albumin or albumin-lactose. The mean diameter of the microspheres prepared with or without emulsifiers ranged from 2 to 10 microm, and the encapsulation efficiency of insulin was between 60% and 75%, respectively. The analysis of microsphere content after processing showed that insulin did not undergo any chemical modification within microspheres. The use of lactose alone led to the formation of highly viscous droplets that coalesced during the purification step. The water extraction procedures successfully produced insulin-loaded hydrophilic microspheres allowing the preservation of peptide stability. The type of excipient and the size of the disperse phase of the primary w/o emulsion were crucial determinants of microsphere characteristics.

Combined high-power ultrasound and high-pressure homogenization nanoemulsification: The effect of energy density, oil content and emulsifier type and content.

PubMed

Calligaris, Sonia; Plazzotta, Stella; Valoppi, Fabio; Anese, Monica

2018-05-01

Combinations of ultrasound (US) and high-pressure homogenization (HPH) at low-medium energy densities were studied as alternative processes to individual US and HPH to produce Tween 80 and whey protein stabilized nanoemulsions, while reducing the energy input. To this aim, preliminary trials were performed to compare emulsification efficacy of single and combined HPH and US treatments delivering low-medium energy densities. Results highlighted the efficacy of US-HPH combined process in reducing the energy required to produce nanoemulsions stabilized with both Tween 80 and whey protein isolate. Subsequently, the effect of emulsifier content (1-3% w/w), oil amount (10-20% w/w) and energy density (47-175 MJ/m 3 ) on emulsion mean particle diameter was evaluated by means of a central composite design. Particles of 140-190 nm were obtained by delivering 175 MJ/m 3 energy density at emulsions containing 3% (w/w) Tween 80 and 10% (w/w) oil. In the case of whey protein isolate stabilized emulsions, a reduced emulsifier amount (1% w/w) and intermediate energy density (120 MJ/m 3 ) allowed a minimum droplet size around 220-250 nm to be achieved. Results showed that, in both cases, at least 50% of the energy density should be delivered by HPH to obtain the minimum particle diameter. Copyright © 2018 Elsevier Ltd. All rights reserved.

Surface-modified solid lipid nanoparticles for oral delivery of docetaxel: enhanced intestinal absorption and lymphatic uptake

PubMed Central

Cho, Hyun-Jong; Park, Jin Woo; Yoon, In-Soo; Kim, Dae-Duk

2014-01-01

Docetaxel is a potent anticancer drug, but development of an oral formulation has been hindered mainly due to its poor oral bioavailability. In this study, solid lipid nanoparticles (SLNs) surface-modified by Tween 80 or D-alpha-tocopheryl poly(ethylene glycol 1000) succinate (TPGS 1000) were prepared and evaluated in terms of their feasibility as oral delivery systems for docetaxel. Tween 80-emulsified and TPGS 1000-emulsified tristearin-based lipidic nanoparticles were prepared by a solvent-diffusion method, and their particle size distribution, zeta potential, drug loading, and particle morphology were characterized. An in vitro release study showed a sustained-release profile of docetaxel from the SLNs compared with an intravenous docetaxel formulation (Taxotere®). Tween 80-emulsified SLNs showed enhanced intestinal absorption, lymphatic uptake, and relative oral bioavailability of docetaxel compared with Taxotere in rats. These results may be attributable to the absorption-enhancing effects of the tristearin nanoparticle. Moreover, compared with Tween 80-emulsified SLNs, the intestinal absorption and relative oral bioavailability of docetaxel in rats were further improved in TPGS 1000-emulsified SLNs, probably due to better inhibition of drug efflux by TPGS 1000, along with intestinal lymphatic uptake. Taken together, it is worth noting that these surface-modified SLNs may serve as efficient oral delivery systems for docetaxel. PMID:24531717

Influence of interfacial and bulk properties of cellulose ethers on lipolysis of oil-in-water emulsions.

PubMed

Torcello-Gómez, Amelia; Foster, Timothy J

2016-06-25

Cellulose ethers are usually used as secondary emulsifiers. Different types of commercial hydroxypropylmethylcellulose (HPMC) have been used here as the main emulsifier of oil-in-water emulsions to probe their impact on the lipid digestibility under simulated intestinal conditions. The droplet size distribution and ζ-potential of the emulsions subjected to in-vitro lipolysis have been compared with that of control samples (non-digested). The lipolysis has been quantified over time by means of the pH-stat method. The displacement of HPMC from the oil-water interface by bile salts has been assessed by interfacial tension technique. Results show that HPMC delays the lipid digestion of emulsions regardless of the Mw and methoxyl content. The destabilisation of emulsions under intestinal conditions as well as the resistance of HPMC to be displaced from the emulsion interface by bile salts may contribute to this feature. This provides new insights into the mechanisms whereby dietary fibre reduces fat absorption. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of different composition of ternary mixtures of emulsifying salts on the consistency of processed cheese spreads manufactured from Swiss-type cheese with different degrees of maturity.

PubMed

Salek, R N; Černíková, M; Maděrová, S; Lapčík, L; Buňka, F

2016-05-01

The scope of this work was to investigate the dependence of selected textural (texture profile analysis, TPA) and viscoelastic properties of processed cheese on the composition of ternary mixtures of emulsifying salts [disodium hydrogenphosphate, DSP; tetrasodium diphosphate, TSPP; sodium salt of polyphosphate (with mean length n ≈ 20), P20; and trisodium citrate, TSC] during a 60-d storage period (6±2°C). The processed cheese samples [40% wt/wt dry matter (DM) content, 50% wt/wt fat in DM content] were manufactured using Swiss-type cheese (as the main raw material) with 4 different maturity degrees (4, 8, 12, and 16 wk of ripening). Moreover, the pH of the samples was adjusted (the target values within the range of 5.60-5.80), corresponding to the standard pH values of spreadable processed cheese. With respect to the individual application of emulsifying salts (regardless of the maturity degree of the Swiss-type cheese applied), the samples prepared with P20 were the hardest, followed by those prepared with TSPP, TSC, and DSP. Furthermore, a specific ratio of DSP:TSPP (1:1) led to a significant increase in the hardness of the samples. On the whole, the hardness of all processed cheese samples increased with the prolonging storage period, whereas their hardness significantly dropped with the rising ripening stage of the raw material utilized. In all of the cases, the trends of hardness development remained analogous, and only the absolute values differed significantly. Moreover, the findings of TPA were in accordance with those of the rheological analysis. In particular, the specific ratio of DSP:TSPP (1:1) resulted in the highest gel strength and interaction factor values, followed by P20, TSPP, TSC, and DSP (used individually), reporting the same trend which was demonstrated by TPA. The monitored values of the gel strength and interaction factor decreased with the increasing maturity degree of the Swiss-type cheese used. The intensity of the rigidity of the samples showed an analogous relationship to the intensity of the gel strength; the higher the gel strength of the sample, the more inflexible the product is expected to be. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Iron-binding antioxidant capacity is impaired in diabetes mellitus.

PubMed

Van Campenhout, Ann; Van Campenhout, Christel; Lagrou, Albert R; Moorkens, Greta; De Block, Christophe; Manuel-y-Keenoy, Begoña

2006-05-15

Increased lipid peroxidation contributes to diabetic complications and redox-active iron is known to play an important role in catalyzing peroxidation reactions. We aimed to investigate if diabetes affects the capacity of plasma to protect against iron-driven lipid peroxidation and to identify underlying factors. Glycemic control, serum iron, proteins involved in iron homeostasis, plasma iron-binding antioxidant capacity in a liposomal model, and non-transferrin-bound iron were measured in 40 type 1 and 67 type 2 diabetic patients compared to 100 nondiabetic healthy control subjects. Iron-binding antioxidant capacity was significantly lower in the plasma of diabetic subjects (83 +/- 6 and 84 +/- 5% in type 1 and type 2 diabetes versus 88 +/- 6% in control subjects, p < 0.0005). The contribution of transferrin, ceruloplasmin, and albumin concentrations to the iron-binding antioxidant capacity was lost in diabetes (explaining only 4.2 and 6.3% of the variance in type 1 and type 2 diabetes versus 13.9% in control subjects). This observation could not be explained by differences in Tf glycation, lipid, or inflammatory status and was not associated with higher non-transferrin-bound iron levels. Iron-binding antioxidant capacity is decreased in diabetes mellitus.

Evaluation of thermal gelation behavior of different cellulose ether polymers by rheology

NASA Astrophysics Data System (ADS)

Balaghi, S.; Edelby, Y.; Senge, B.

2014-05-01

Hydroxypropylmethylcellulose (HPMC) and Methylcellulose (MC) are cellulose ethers which can be dispersed in water and used as thickeners, emulsifiers, binders, film formers, and water-retention agents due to their hydrophilic and hydrophobic characteristics. In this study, various types of HPMCs, in comparison with two types of MCs were examined. The formed gels of the different cellulose ethers showed specific and various structural formation and network properties. The degree of methylation (Meth.) and hydroxypropylation (HyPr.) affected drastically the heat-induced gelation of the examined cellulose ethers.

Covalent modification of soy protein isolate by (-)-epigallocatechin-3-gallate: effects on structural and emulsifying properties.

PubMed

Tao, Fei; Jiang, He; Chen, Wenwei; Zhang, Yongyong; Pan, Jiarong; Jiang, Jiaxin; Jia, Zhenbao

2018-05-07

Soy protein isolate (SPI) has promising applications in various food products because of its excellent functional properties and nutritional quality. The structural and emulsifying properties of covalently modified SPI by (-)-epigallocatechin-3-gallate (EGCG) were investigated. SPI was covalently modified by EGCG under alkaline conditions. SDS-PAGE analysis revealed that EGCG modification caused cross-linking of SPI proteins. Circular dichroism spectra demonstrated that the secondary structure of SPI proteins was changed by EGCG modification. In addition, the modifications resulted in the perturbation of the tertiary structure of SPI as evidenced by intrinsic fluorescence spectra and surface hydrophobicity measurements. Oil-in-water emulsions of modified SPI had smaller droplet sizes and better creaming stability compared to those from unmodified SPI. The covalent modification by EGCG improved the emulsifying property of SPI. This study provided an innovative approach for improving the emulsifying properties of proteins. This article is protected by copyright. All rights reserved.

Influence of emulsifiers on the characteristics of polyurethane structures used as drug carrier

PubMed Central

2013-01-01

Background Emulsifiers have a significant role in the emulsion polymerization by reducing the interfacial tension thus increasing the stability of colloidal dispersions of polymer nanostructures. This study evaluates the impact of four emulsifiers on the characteristics of polyurethane hollow structures used as drug delivery system. Results Polyurethane (PU) structures with high stability and sizes ranging from nano- to micro-scale were obtained by interfacial polyaddition combined with spontaneous emulsification. The pH of PU aqueous solutions (0.1% w/w) was slightly acidic, which is acceptable for products intended to be used on human skin. Agglomerated structures with irregular shapes were observed by scanning electron microscopy. The synthesized structures have melting points between 245-265°C and reveal promising results in different evaluations (TEWL, mexametry) on murine skin. Conclusions In this study hollow PU structures of reduced noxiousness were synthesized, their size and stability being influenced by emulsifiers. Such structures could be used in the pharmaceutical field as future drug delivery systems. PMID:23575277

Effect of dynamic high pressure on emulsifying and encapsulant properties of cashew tree gum.

PubMed

Porto, Bruna Castro; Cristianini, Marcelo

2018-04-15

Dynamic high pressure (DHP) has been applied in the physical modification of biopolymers as polysaccharides, proteins and gums. It is known that DHP is able to promote degradation of polysaccharides (e.g. molecular weight reduction). However, few studies have assessed the effect of DHP on the emulsifying and encapsulating properties of polysaccharides. Thus, this study aimed to investigate the effect of DHP on the emulsifying (average droplet size and particle size distribution, optical and confocal scanning laser microscopy, rheology, zeta potential and electric conductivity, creaming index, and turbidity) and encapsulating (scanning electronic microscopy, flavor retention, average droplet size, and particle size distribution) properties of cashew tree gum (CG). The application of DHP process improved the emulsifying capacity of cashew tree gum (CG) by reducing the medium droplet size (D3,2 and D4,3), increasing the turbidity and improving the emulsion stability. However, no effect of DHP was observed on the encapsulating capacity of CG. Copyright © 2018 Elsevier Ltd. All rights reserved.

Food protein-stabilized nanoemulsions as potential delivery systems for poorly water-soluble drugs: preparation, in vitro characterization, and pharmacokinetics in rats

PubMed Central

He, Wei; Tan, Yanan; Tian, Zhiqiang; Chen, Lingyun; Hu, Fuqiang; Wu, Wei

2011-01-01

Nanoemulsions stabilized by traditional emulsifiers raise toxicological concerns for long-term treatment. The present work investigates the potential of food proteins as safer stabilizers for nanoemulsions to deliver hydrophobic drugs. Nanoemulsions stabilized by food proteins (soybean protein isolate, whey protein isolate, β-lactoglobulin) were prepared by high-pressure homogenization. The toxicity of the nanoemulsions was tested in Caco-2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide viability assay. In vivo absorption in rats was also evaluated. Food protein-stabilized nanoemulsions, with small particle size and good size distribution, exhibited better stability and biocompatibility compared with nanoemulsions stabilized by traditional emulsifiers. Moreover, β-lactoglobulin had a better emulsifying capacity and biocompatibility than the other two food proteins. The pancreatic degradation of the proteins accelerated drug release. It is concluded that an oil/water nanoemulsion system with good biocompatibility can be prepared by using food proteins as emulsifiers, allowing better and more rapid absorption of lipophilic drugs. PMID:21468355

Food protein-stabilized nanoemulsions as potential delivery systems for poorly water-soluble drugs: preparation, in vitro characterization, and pharmacokinetics in rats.

PubMed

He, Wei; Tan, Yanan; Tian, Zhiqiang; Chen, Lingyun; Hu, Fuqiang; Wu, Wei

2011-01-01

Nanoemulsions stabilized by traditional emulsifiers raise toxicological concerns for long-term treatment. The present work investigates the potential of food proteins as safer stabilizers for nanoemulsions to deliver hydrophobic drugs. Nanoemulsions stabilized by food proteins (soybean protein isolate, whey protein isolate, β-lactoglobulin) were prepared by high-pressure homogenization. The toxicity of the nanoemulsions was tested in Caco-2 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide viability assay. In vivo absorption in rats was also evaluated. Food protein-stabilized nanoemulsions, with small particle size and good size distribution, exhibited better stability and biocompatibility compared with nanoemulsions stabilized by traditional emulsifiers. Moreover, β-lactoglobulin had a better emulsifying capacity and biocompatibility than the other two food proteins. The pancreatic degradation of the proteins accelerated drug release. It is concluded that an oil/water nanoemulsion system with good biocompatibility can be prepared by using food proteins as emulsifiers, allowing better and more rapid absorption of lipophilic drugs.

Pickering-type water-in-oil-in-water multiple emulsions toward multihollow nanocomposite microspheres.

PubMed

Maeda, Hayata; Okada, Masahiro; Fujii, Syuji; Nakamura, Yoshinobu; Furuzono, Tsutomu

2010-09-07

Multihollow hydroxyapatite (HAp)/poly(L-lactic acid) (PLLA) nanocomposite microspheres were readily fabricated by solvent evaporation from a "Pickering-type" water-in-(dichloromethane solution of PLLA)-in-water multiple emulsion stabilized with HAp nanoparticles. The multiple emulsion was stabilized with the aid of PLLA molecules used as a wettability modifier for HAp nanoparticles, although HAp nanoparticles did not work solely as particulate emulsifiers for Pickering-type emulsions consisting of pure dichloromethane and water. The interaction between PLLA and HAp nanoparticles at the oil-water interfaces plays a crucial role toward the preparation of stable multiple emulsion and multihollow microspheres.

Biogeochemical Modeling of In Situ U(VI) Reduction and Immobilization with Emulsified Vegetable Oil as the Electron Donor at a Field Site in Oak Ridge, Tennessee

NASA Astrophysics Data System (ADS)

Tang, G.; Parker, J.; Wu, W.; Schadt, C. W.; Watson, D. B.; Brooks, S. C.; Orifrc Team

2011-12-01

A comprehensive biogeochemical model was developed to quantitatively describe the coupled hydrologic, geochemical and microbiological processes that occurred following injection of emulsified vegetable oil (EVO) as the electron donor to immobilize U(VI) at the Oak Ridge Integrated Field Research Challenge site (ORIFRC) in Tennessee. The model couples the degradation of EVO, production and oxidation of long-chain fatty acids (LCFA), glycerol, hydrogen and acetate, reduction of nitrate, manganese, ferrous iron, sulfate and uranium, and methanoganesis with growth of multiple microbial groups. The model describes the evolution of geochemistry and microbial populations not only in the aqueous phase as typically observed, but also in the mineral phase and therefore enables us to evaluate the applicability of rates from the literature for field scale assessment, estimate the retention and degradation rates of EVO and LCFA, and assess the influence of the coupled processes on fate and transport of U(VI). Our results suggested that syntrophic bacteria or metal reducers might catalyze LCFA oxidation in the downstream locations when sulfate was consumed, and competition between methanogens and others for electron donors and slow growth of methanogen might contribute to the sustained reducing condition. Among the large amount of hydrologic, geochemical and microbiological parameter values, the initial biomass, and the interactions (e.g., inhibition) of the microbial functional groups, and the rate and extent of Mn and Fe oxide reduction appear as the major sources of uncertainty. Our model provides a platform to conduct numerical experiments to study these interactions, and could be useful for further iterative experimental and modeling investigations into the bioreductive immobiliztion of radionuclide and metal contaminants in the subsurface.

THE INFLUENCE OF CARBON BURNOUT ON SUBMICRON PARTICLE FORMATION FROM EMULSIFIED FUEL OIL COMBUSTION

EPA Science Inventory

The paper gives results of an examination of particle behavior and particle size distributions from the combustion of different fuel oils and emulsified fuels in three experimental combusators. Results indicate that improved carbon (C) burnout from fule oil combustion, either by...

In situ SERS detection of emulsifiers at lipid interfaces using label-free amphiphilic gold nanoparticles.

PubMed

Li, Yue; Driver, Michael; Winuprasith, Thunnalin; Zheng, Jinkai; McClements, David Julian; He, Lili

2014-10-21

Herein, we fabricated amphiphilic gold nanoparticles (GNPs) that can self-assemble at oil-water interfaces. We applied those GNPs for in situ SERS detection of emulsifier molecules within the interfacial region of oil in water (O/W) emulsion systems.

Peroxidase mediated conjugation of corn fibeer gum and bovine serum albumin to improve emulsifying properties

USDA-ARS?s Scientific Manuscript database

The emulsifying properties of corn fiber gum (CFG), a naturally-occurring polysaccharide protein complex, were improved by kinetically controlled formation of hetero-covalent linkages with bovine serum albumin (BSA), using horseradish peroxidase. The formation of hetero-crosslinked CFG-BSA conjugate...

Enhanced absorption of n-3 fatty acids from emulsified compared with encapsulated fish oil

USDA-ARS?s Scientific Manuscript database

The omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have important nutrition and disease management properties. Presently fish oil (FO) supplementation relies on capsular triglyceride. Flavored emulsified lipid preparations may provide an improved approach to FO del...

Emulsifying conditions and processing parameters optimisation of kenaf seed oil-in-water nanoemulsions stabilised by ternary emulsifier mixtures.

PubMed

Cheong, Ai M; Tan, Chin P; Nyam, Kar L

2018-01-01

Kenaf ( Hibiscus cannabinus L.) seed oil has been proven for its multi-pharmacological benefits; however, its poor water solubility and stability have limited its industrial applications. This study was aimed to further improve the stability of pre-developed kenaf seed oil-in-water nanoemulsions by using food-grade ternary emulsifiers. The effects of emulsifier concentration (1, 5, 10, 15% w/w), homogenisation pressure (16,000, 22,000, 28,000 psi), and homogenisation cycles (three, four, five cycles) were studied to produce high stability of kenaf seed oil-in-water nanoemulsions using high pressure homogeniser. Generally, results showed that the emulsifier concentration and homogenisation conditions had great effect ( p < 0.05) on the particle sizes, polydispersity index and hence the physical stability of nanoemulsions. Homogenisation parameters at 28,000 psi for three cycles produced the most stable homogeneous nanoemulsions that were below 130 nm, below 0.16, and above -40 mV of particle size, polydispersity index, and zeta potential, respectively. Field emission scanning electron microscopy micrograph showed that the optimised nanoemulsions had a good distribution within nano-range. The optimised nanoemulsions were proved to be physically stable for up to six weeks of storage at room temperature. The results from this study also provided valuable information in producing stable kenaf seed oil nanoemulsions for the future application in food and nutraceutical industries.

Egress route of emulsified 20 centistokes silicone oil from anterior chamber of rabbit.

PubMed

Ohira, A; Chihara, E; Soji, T

1994-07-01

Silicone oil is used in recent clinical practice, however, it may cause adverse reactions in the eyes. When the high viscosity silicone oil is contaminated with low molecular weight silicone oil, the contamination may cause ocular toxicity or elevation of the intraocular pressure. To obtain information on the distribution of this preparation, emulsified 20 centistokes silicone oil was injected into the anterior chamber of rabbit eyes. The silicone oil droplets were visualized by light and electron microscopy by using oil soluble phthalocyanine blue. This copper containing dye remains in the tissue after removal of the silicone oil by organic solvents. Two and 4 weeks after an injection, the silicone emulsion was observed as numerous small vacuoles with blue precipitate at the margin of vacuoles within elongated trabecular endothelial cells, fibroblasts along the route of uveoscleral outflow and cells of the iris. Three hours after the injection, only a few vacuoles were present in these cells. These results demonstrated that the emulsified silicone oil leaves the anterior chamber through the conventional and unconventional routes. Phagocytosis by the trabecular endothelial cells and fibroblasts along the uveoscleral route caused an accumulation of the emulsified silicone oil in these cells. With chronic exposure to emulsified silicone oil, changes in the trabecular meshwork may lead to a reduction in the outflow of aqueous humor and cause glaucoma.

The research about microscopic structure of emulsion membrane in O/W emulsion by NMR and its influence to emulsion stability.

PubMed

Xie, Yiqiao; Chen, Jisheng; Zhang, Shu; Fan, Kaiyan; Chen, Gang; Zhuang, Zerong; Zeng, Mingying; Chen, De; Lu, Longgui; Yang, Linlin; Yang, Fan

2016-03-16

This paper discussed the influence of microstructure of emulsion membrane on O/W emulsion stability. O/W emulsions were emulsified with equal dosage of egg yolk lecithin and increasing dosage of co-emulsifier (oleic acid or HS15). The average particle size and centrifugal stability constant of emulsion, as well as interfacial tension between oil and water phase were determined. The microstructure of emulsion membrane had been studied by (1)H/(13)C NMR, meanwhile the emulsion droplets were visually presented with TEM and IFM. With increasing dosage of co-emulsifier, emulsions showed two stable states, under which the signal intensity of characteristic group (orient to lipophilic core) of egg yolk lecithin disappeared in NMR of emulsions, but that (orient to aqueous phase) of co-emulsifiers only had some reduction at the second stable state. At the two stable states, the emulsion membranes were neater in TEM and emulsion droplets were rounder in IFM. Furthermore, the average particle size of emulsions at the second stable state was bigger than that at the first stable state. Egg yolk lecithin and co-emulsifier respectively arranged into monolayer and bilayer emulsion membrane at the two stable states. The microstructure of emulsion membrane was related to the stability of emulsion. Copyright © 2016 Elsevier B.V. All rights reserved.

Fabrication of Concentrated Fish Oil Emulsions Using Dual-Channel Microfluidization: Impact of Droplet Concentration on Physical Properties and Lipid Oxidation.

PubMed

Liu, Fuguo; Zhu, Zhenbao; Ma, Cuicui; Luo, Xiang; Bai, Long; Decker, Eric Andrew; Gao, Yanxiang; McClements, David Julian

2016-12-21

Chemically unstable lipophilic bioactives, such as polyunsaturated lipids, often have to be encapsulated in emulsion-based delivery systems before they can be incorporated into foods, supplements, and pharmaceuticals. The objective of this study was to develop highly concentrated emulsion-based fish oil delivery systems using natural emulsifiers. Fish oil-in-water emulsions were fabricated using a highly efficient dual-channel high-pressure microfluidizer. The impact of oil concentration on the formation, physical properties, and oxidative stability of fish oil emulsions prepared using two natural emulsifiers (quillaja saponins and rhamnolipids) and one synthetic emulsifier (Tween-80) was examined. The mean droplet size, polydispersity, and apparent viscosity of the fish oil emulsions increased with increasing oil content. However, physically stable emulsions with high fish oil levels (30 or 40 wt %) could be produced using all three emulsifiers, with rhamnolipids giving the smallest droplet size (d < 160 nm). The stability of the emulsions to lipid oxidation increased as the oil content increased. The oxidative stability of the emulsions also depended on the nature of the emulsifier coating the lipid droplets, with the oxidative stability decreasing in the following order: rhamnolipids > saponins ≈ Tween-80. These results suggest that rhamnolipids may be particularly effective at producing emulsions containing high concentrations of ω-3 polyunsaturated fatty acids-rich fish oil.

The influence of carbohydrate-based fat replacers with and without emulsifiers on the quality characteristics of lowfat cake.

PubMed

Khalil, A H

1998-01-01

Physical and sensory characteristics of cakes prepared with either the carbohydrate-based fat replacers N-Flate, Paselli MD 10 and Litesse (0, 25, 50 and 75% of fat weight) or fat replacers plus emulsifier (mono- and diglycerides; 0 and 3% of flour weight) were studied. Specific gravity of the batter was significantly (p < or = 0.05) improved by using the carbohydrate-based fat replacers, especially at the 25 and 50% replacement levels. The combination of the emulsifier with either Paselli MD 10 or Litesse also enhanced the specific gravity. Cakes prepared with fat replacers at the 25 and 50% levels had higher volumes, specific volume and standing heights than those of the control. Cakes prepared with fat replacers at the 25, 50 and 75% levels were more compressible than the control. Cakes prepared with Paselli MD 10 had the highest volumes, specific volume, standing heights and compressibilities. Incorporation of emulsifier with fat replacers improved cake volumes, standing heights and compressibilities. Cakes prepared with fat replacers exhibited higher crust and crumb color values compared to the control. Cakes prepared with 25 or 50% fat replacers had higher mean scores for flavor, softness and eating quality than the control. Incorporation of emulsifier with fat replacers did not affect the crust color, crumb color and flavor, but significantly (p < or = 0.05) improved softness and eating quality.

Physical, rheological, functional and film properties of a novel emulsifier: Frost grape polysaccharide (FGP) from Vitis riparia Michx

USDA-ARS?s Scientific Manuscript database

A novel emulsifier, Frost grape polysaccharide (FGP), isolated from natural exudate of the species Vitis riparia Michx, was physically and rheologically characterized. The determination of the physical, structural, thermodynamic, emulsification, film, and rheological properties of FGP provide essent...

21 CFR 178.3400 - Emulsifiers and/or surface-active agents.

Code of Federal Regulations, 2014 CFR

2014-04-01

... paperboard. α-[p-(1,1,3,3-Tetramethylbutyl)phenyl] omega-hydroxypoly(oxyethylene) produced by the... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Emulsifiers and/or surface-active agents. 178.3400... substances: List of substances Limitations α-Alkyl-, α-alkenyl-, and α-alkylaryl-omega-hydroxypoly...

21 CFR 172.838 - Polysorbate 65.

Code of Federal Regulations, 2011 CFR

2011-04-01

... follows: (1) As an emulsifier in ice cream, frozen custard, ice milk, fruit sherbet and nonstandardized... solid-state, edible vegetable fat-water emulsions intended for use as substitutes for milk or cream in... finished edible vegetable fat-water emulsion. (5) As an emulsifier in cake icings and cake fillings, with...

21 CFR 172.838 - Polysorbate 65.

Code of Federal Regulations, 2010 CFR

2010-04-01

... follows: (1) As an emulsifier in ice cream, frozen custard, ice milk, fruit sherbet and nonstandardized... solid-state, edible vegetable fat-water emulsions intended for use as substitutes for milk or cream in... finished edible vegetable fat-water emulsion. (5) As an emulsifier in cake icings and cake fillings, with...

77 FR 30216 - Approval and Promulgation of Air Quality Implementation Plans; Maine; Reasonably Available...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

... them into the Maine SIP: Revised Chapter 131, Cutback Asphalt and Emulsified Asphalt Regulation... recordkeeping requirements, Sulfur oxides, Volatile organic compounds. Dated: May 8, 2012. Ira W. Leighton... begins]. * * * * * * * Chapter 131 Cutback Asphalt and 09/15/2009 05/22/2012 [Insert Emulsified Asphalt...

Enhanced bioavailability of EPA from emulsified fish oil preparations versus capsular triacylglycerol

USDA-ARS?s Scientific Manuscript database

Pre-emulsified fish oil supplements, an alternative to capsular triacylglycerol, may enhance the uptake of LCn3 fatty acids it contains. A randomized, Latin-square crossover design was used to compare the effects of four fish oil supplement preparations on phospholipid (PLFA) and chylomicron fatty ...

The effect of emulsifying salts on the turbidity of a diluted milk system with varying pH and protein concentration.

PubMed

Culler, M D; Saricay, Y; Harte, F M

2017-06-01

Solutions of 10 commonly used emulsifying salts (ES) listed in the Code of Federal Regulations (21CFR133.179) for pasteurized process cheese were tested for their effect on the turbidity of a diluted milk system at different pH and protein concentrations to characterize the conditions that affect micellar structure. Emulsifying salt solutions were made by mixing the ES in a 1-in-20 dilution of water in skim milk ultrafiltrate (3 kDa molecular weight cut-off) to obtain ES concentrations from 0 to 248 mM. Skim milk was added to solutions containing nanopure water, skim milk ultrafiltrate, and a specific ES ranging in concentration from 0 to 248 mM and pH 5, 5.8, 6.8, 7.8, and 8.8. The turbidity of the samples was measured as the optical density at 400 nm immediately after mixing (time, t = 0), after 30 s (t = 30s), and after 30 min (t = 30min). Emulsifying salts were found to cause a decrease in the turbidity of the system, which was modeled using an exponential decay model, where C* represents a threshold salt concentration at which rapid dissociation occurs. At pH values 5.8 and 6.8, the ES caused the greatest decrease in turbidity of the diluted milk system. At pH 5, the ES had the least effect on the turbidity of the system. Sodium hexametaphosphate was found to have the strongest dissociative effect, with a C* value of 0.33 mM for t = 0 at pH 6.8. In contrast, the largest C* value calculated at pH 6.8 was monosodium phosphate at 278.22 mM. Increased time resulted in lower C* values. The model established for this study can be used to predict the dissociation of casein micelles in the presence of various types of ES. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Preparation and optimization of tablets containing a self-nano-emulsifying drug delivery system loaded with rosuvastatin.

PubMed

Salem, Heba F; Kharshoum, Rasha M; Halawa, Abdel Khalek A; Naguib, Demiana M

2018-06-01

Rosuvastatin (ROS) calcium is the latest synthetic drug in the statin group that has an anti-hyperlipidemic activity. It is available as tablets, and its poor aqueous solubility, slow dissolution rate and low-absorption extent result in less than 20% bioavailability and about 80% being excreted unchanged in the feces without absorption. To utilize nanotechnology to reformulate ROS as a self-nano-emulsifying drug delivery system (SNEDDS), and utilizing design optimization to fabricate the SNEDDS as a tablet. The solubility of ROS in different oils, surfactants and co-surfactants was tested. Pseudo-ternary phase diagrams were developed and various SNEDDS formulations were prepared and evaluated regarding globule size, self-emulsification, viscosity and transmittance. The optimized system was examined using transmission electron microscopy. The self-nano-emulsifying tablets were prepared using two types of nano-silica and different percentages of Avicel as a binder and Ac-Di-Sol as a disintegrant. The prepared tablets were evaluated for their physicochemical properties. Bioavailability in human volunteers was assessed. A SNEDDS system was successfully developed with a droplet size range of 15 nm and a composition of 10% Labrafac, 80% Cremophore RH40 and 10% Propylene glycol. The optimized tablet formula contained: hydrophilic nano-silica, 3% Ac-Di-Sol and 30% Avicel. The pharmacokinetic study revealed that the bioavailability was enhanced by more than 2.4-fold compared with the commercially available tablet. Tablets containing SNEDDS loaded with ROS represent a promising novel formula that has higher gastrointestinal absorption and enhanced systemic bioavailability.

Transitions between type A flake, type D flake, and coral graphite eutectic structures in cast irons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, J.S.; Verhoeven, J.D.

1996-09-01

Directional solidification experiments were used to measure the transition velocities between the type A and coral eutectic structures in high-purity cast irons and between the type A and type D eutectic structures in S and Te doped cast irons. Introduction of O into the gas atmosphere was found to have little effect on the A {R_arrow} D transition velocities in S doped alloys, but it produced a strong reduction in the A {R_arrow} coral transition velocities in high-purity irons. Transmission electron microscopy revealed interesting variations in the defect structures of the graphite in the flake irons vs the type ofmore » flake (A or D) and the type of doping element. Scanning Auger microscopy demonstrated that both S and Te segregate to the iron/graphite interface. In the S doped alloys, type A flakes are generally covered with a monolayer of S with patches of O in the form of iron oxide having a thickness on the order of 2 nm. A series of experiments, including examination of fracture surfaces at the quenched solid/liquid growth front, have shown that S segregates to the iron/graphite interfaces from the liquid at the growth front, but O forms at these interfaces during the cooldown. These results are discussed in relation to current models of eutectic growth in cast irons.« less

PfeT, a P1B4 -type ATPase, effluxes ferrous iron and protects Bacillus subtilis against iron intoxication.

PubMed

Guan, Guohua; Pinochet-Barros, Azul; Gaballa, Ahmed; Patel, Sarju J; Argüello, José M; Helmann, John D

2015-11-01

Iron is an essential element for nearly all cells and limited iron availability often restricts growth. However, excess iron can also be deleterious, particularly when cells expressing high affinity iron uptake systems transition to iron rich environments. Bacillus subtilis expresses numerous iron importers, but iron efflux has not been reported. Here, we describe the B. subtilis PfeT protein (formerly YkvW/ZosA) as a P1B4 -type ATPase in the PerR regulon that serves as an Fe(II) efflux pump and protects cells against iron intoxication. Iron and manganese homeostasis in B. subtilis are closely intertwined: a pfeT mutant is iron sensitive, and this sensitivity can be suppressed by low levels of Mn(II). Conversely, a pfeT mutant is more resistant to Mn(II) overload. In vitro, the PfeT ATPase is activated by both Fe(II) and Co(II), although only Fe(II) efflux is physiologically relevant in wild-type cells, and null mutants accumulate elevated levels of intracellular iron. Genetic studies indicate that PfeT together with the ferric uptake repressor (Fur) cooperate to prevent iron intoxication, with iron sequestration by the MrgA mini-ferritin playing a secondary role. Protection against iron toxicity may also be a key role for related P1B4 -type ATPases previously implicated in bacterial pathogenesis. © 2015 John Wiley & Sons Ltd.

Effect of emulsifier and viscosity on oil separation in ready-to-use therapeutic food

USDA-ARS?s Scientific Manuscript database

Oil separation is a common food quality problem in ready-to-use therapeutic food (RUTF), the shelf-stable, peanut-based food used to treat severe acute malnutrition in home settings. Our objective was to evaluate the effect on oil separation of three emulsifiers at different concentrations in RUTF. ...

21 CFR 178.3400 - Emulsifiers and/or surface-active agents.

Code of Federal Regulations, 2010 CFR

2010-04-01

... paperboard. α-[p-(1,1,3,3-Tetramethylbutyl)phenyl] omega-hydroxypoly(oxyethylene) produced by the... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Emulsifiers and/or surface-active agents. 178.3400...-alkylaryl-omega-hydroxypoly(oxyethylene) mixture consisting of 30 weight pct of α-(2,4,6-triisobutylphenyl...

21 CFR 178.3400 - Emulsifiers and/or surface-active agents.

Code of Federal Regulations, 2013 CFR

2013-04-01

... paperboard. α-[p-(1,1,3,3-Tetramethylbutyl)phenyl] omega-hydroxypoly(oxyethylene) produced by the... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Emulsifiers and/or surface-active agents. 178.3400...-alkylaryl-omega-hydroxypoly(oxyethylene) mixture consisting of 30 weight pct of α-(2,4,6-triisobutylphenyl...

21 CFR 178.3400 - Emulsifiers and/or surface-active agents.

Code of Federal Regulations, 2011 CFR

2011-04-01

... paperboard. α-[p-(1,1,3,3-Tetramethylbutyl)phenyl] omega-hydroxypoly(oxyethylene) produced by the... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Emulsifiers and/or surface-active agents. 178.3400...-alkylaryl-omega-hydroxypoly(oxyethylene) mixture consisting of 30 weight pct of α-(2,4,6-triisobutylphenyl...

21 CFR 178.3400 - Emulsifiers and/or surface-active agents.

Code of Federal Regulations, 2012 CFR

2012-04-01

... paperboard. α-[p-(1,1,3,3-Tetramethylbutyl)phenyl] omega-hydroxypoly(oxyethylene) produced by the... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Emulsifiers and/or surface-active agents. 178.3400...-alkylaryl-omega-hydroxypoly(oxyethylene) mixture consisting of 30 weight pct of α-(2,4,6-triisobutylphenyl...

Aqueous vinylidene fluoride polymer coating composition

NASA Technical Reports Server (NTRS)

Bartoszek, Edward J. (Inventor); Christofas, Alkis (Inventor)

1978-01-01

A water-based coating composition which may be air dried to form durable, fire resistant coatings includes dispersed vinylidene fluoride polymer particles, emulsified liquid epoxy resin and a dissolved emulsifying agent for said epoxy resin which agent is also capable of rapidly curing the epoxy resin upon removal of the water from the composition.

Application of multiwalled carbon nanotubes and its magnetite derivative for emulsified oil removal from produced water.

PubMed

Ibrahim, Taleb H; Sabri, Muhammad A; Khamis, Mustafa I

2018-05-10

Multiwalled carbon nanotubes and their magnetite derivatives were employed as adsorbents for emulsified oil removal from produced water. The experimental parameters for maximum emulsified oil removal efficiency and effective regeneration of these adsorbents were determined. The optimum parameters in terms of adsorbent dosage, contact time, salinity, pH and temperature were 3.0 g/L, 20.0 min, 0 ppm, 7.0 and 25°C for both adsorbents. Due to their low density, multiwalledcarbon nanotubes could not be successfully employed in packed bed columns. The magnetite derivative has a larger density and hence, for the removal of emulsified oil from produced water packed bed column studies were performed utilizing multiwalled carbon magnetite nanotubes. The packed bed column efficiency and behaviour were evaluated using Thomas, Clark, Yan et al. and Bohart and Adams models. The Yan model was found to best describe the column experimental data. The adsorbents were regenerated using n-hexane and reused several times for oil removal from produced water without any significant decrease in their initial adsorption capacities.

Studies on gum of Moringa oleifera for its emulsifying properties.

PubMed

Panda, Dibya Sundar

2014-04-01

Emulsion has been a form of presenting water insoluble substances for a long period of time. Now a day, it has been a way of presenting various intravenous additives and diagnostic agents in X-ray examinations. Various substances can be used as emulsifying agent, which can be operationally defined as a stabilizer of the droplets formed of the internal phase. Gum from Moringa oleifera was evaluated for its emulsifying properties. Castor oil emulsions 30 percent (o/w), containing 2 to 4% Moringa oleifera gum was prepared. Emulsions containing equivalent concentration of acacia were also prepared for comparison. All the emulsions prepared were stored at room temperature and studied for stability at various time intervals for 8 weeks. The prepared emulsions were evaluated for creaming rate, globule size and rate of coalescence. 23 factorial design was chosen to investigate the effects of centrifugation, pH, temperature changes and electrolytes on the creaming rate and globule size. The results of the investigations show that the gum of Moringa oleifera possesses better emulsifying properties as compared to gum acacia. Gum of Moringa oleifera could be used in pharmaceutical and non-pharmaceutical preparation.

Development and evaluation of granule and emulsifiable concentrate formulations containing Derris elliptica extract for crop pest control.

PubMed

Wiwattanapatapee, Ruedeekorn; Sae-Yun, Attawadee; Petcharat, Jiraporn; Ovatlarnporn, Chitchamai; Itharat, Arunporn

2009-12-09

Derris elliptica Benth. extracts containing rotenone have long been used as natural insecticides, but time-consuming preparation processes and the short shelf life of the extract limit their use in pest control. In this study, stable water-dispersible granules and emulsifiable concentrate liquids containing Derris extract (equivalent to 5% w/w of rotenone) were developed with simple techniques. Accelerated degradation kinetics of rotenone in the Derris extract, and in both formulations, indicated that its degradation followed first-order kinetics. The predicted half-life (t(1/2)) and shelf life (t(90%)) at 30 degrees C of rotenone in Derris extract were 520 and 79 days, respectively. Derris granules and emulsifiable concentrate clearly prolong the stability of rotenone 8-fold (t(90%) = 633 days) and 1.4-fold (t(90%) = 110 days), respectively. The study of rotenone degradation after application onto plants indicated that both formulations would be effective for up to 3 days after spraying. Preliminary efficacy testing indicated that the Derris emulsifiable concentrate was clearly more effective than Derris water-dispersible granules in controlling Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae).

The mannoprotein of Saccharomyces cerevisiae is an effective bioemulsifier.

PubMed Central

Cameron, D R; Cooper, D G; Neufeld, R J

1988-01-01

The mannoprotein which is a major component of the cell wall of Saccharomyces cerevisiae is an effective bioemulsifier. Mannoprotein emulsifier was extracted in a high yield from whole cells of fresh bakers' yeast by two methods, by autoclaving in neutral citrate buffer and by digestion with Zymolase (Miles Laboratories; Toronto, Ontario, Canada), a beta-1,3-glucanase. Heat-extracted emulsifier was purified by ultrafiltration and contained approximately 44% carbohydrate (mannose) and 17% protein. Treatment of the emulsifier with protease eliminated emulsification. Kerosene-in-water emulsions were stabilized over a broad range of conditions, from pH 2 to 11, with up to 5% sodium chloride or up to 50% ethanol in the aqueous phase. In the presence of a low concentration of various solutes, emulsions were stable to three cycles of freezing and thawing. An emulsifying agent was extracted from each species or strain of yeast tested, including 13 species of genera other than Saccharomyces. Spent yeast from the manufacture of beer and wine was demonstrated to be a possible source for the large-scale production of this bioemulsifier. PMID:3046488

Enhance the anti-microorganism activity of cinnamon oil by xanthan gum as emulsifying agent

NASA Astrophysics Data System (ADS)

Lieu, Dong M.; Dang, Thuy T. K.; Nguyen, Huong T.

2018-04-01

The aim of this study was to evaluate the effect of emulsifying agents (tween 20, DMSO (Dimethyl Sulfoxide) and xanthan gum) to inhibit Escherichia coli; Staphylococcus aureus; Saccharomyces cerevisiae and Aspergillus niger by cinnamon oil (Cinnamomum Cassia). Cinnamon oil was added in the emulsifying agents independently: tween 20 (0.3% v/v). DMSO (0.3% v/v) and xanthan gum (0.3% w/v) at different concentrations and evaluated their anti-microorganism activity by agar disk diffusion, mycelial growth inhibition and growth inhibition in liquid phase. The result indicated that, cinnamon oil diluted in different emulsifying agents showed the difference of the anti-microorganism activity, in which DMSO showed the lowest result. Xanthan gum and tween 20 show good stable emulsion. The anti-microorganism effect of cinnamon oil in tween 20 and xanthan gum was not significant difference. However, cinnamon oil in xanthan gum showed anti-microorganism activity better than tween 20 at low concentration in agar disk diffusion. This suggests that, cinnamon oil could be encapsulated by xanthan gum to enhance the anti-microorganism activity.

Adsorption at the biocompatible α-pinene-water interface and emulsifying properties of two eco-friendly surfactants.

PubMed

Trujillo-Cayado, Luis Alfonso; Ramírez, Pablo; Alfaro, María Carmen; Ruíz, Manuela; Muñoz, José

2014-10-01

In this contribution, we provide an accurate characterization at the α-pinene/water interface of two commercial polyoxytheylene glycerol ester surfactants which differ in the number of ethylene oxide (EO) groups, comprising a systematic analysis of interfacial pressure isotherms, dynamic curves, interfacial rheology and emulsifying properties. Polyoxyethylene glycerol esters derived from cocoa oil are non-ionic surfactants obtained from a renewable source which fulfill the environmental and toxicological requirements to be used as eco-friendly emulsifying agents. α-Pinene is a renewable biosolvent completely insoluble in water, which could find numerous applications. Interfacial rheology and equilibrium interfacial pressure data fitted a rigorous reorientation model that assumes that the surfactant molecules, when adsorbed at the interface, can acquire two orientations. The surfactant with the highest number of EO groups (Levenol C201) turned out to be more surface active at the α-pinene/water interface. In addition, the surfactant with the lowest number of EO groups (Levenol H&B) is solubilized into the adjacent oil phase. Slightly concentrated α-pinene emulsions were obtained using both surfactants. Nevertheless, more stable α-pinene emulsions with smaller droplet sizes and lower polidispersity were obtained when Levenol C201 was used as emulsifier instead of Levenol H&B. The systematic characterization presented in this work provides important new findings on the interfacial and emulsifying properties of polyoxytheylene glycerol ester surfactants, which can be applied in the rational development of new biocompatible products. Copyright © 2014 Elsevier B.V. All rights reserved.

Antimicrobial activity of thyme oil co-nanoemulsified with sodium caseinate and lecithin.

PubMed

Xue, Jia; Michael Davidson, P; Zhong, Qixin

2015-10-01

Emulsions of essential oils are investigated as potential intervention strategies to improve food safety and are preferably prepared from generally-recognized-as-safe emulsifiers. Stable thyme oil nanoemulsions can be prepared using combinations of sodium caseinate (NaCas) and soy lecithin. The objective of the present research was to study the antimicrobial activity of these nanoemulsions and understand the impacts of emulsifier concentrations. 10 g/L thyme oil was emulsified using combinations of (A) 4% w/v NaCas and 0.5% w/v lecithin or (B) 2% w/v NaCas and 0.25% w/v lecithin by high shear homogenization. Combination A resulted in a transparent emulsion with a mean droplet diameter of 82.5 nm, while it was turbid for the Combination B with an average diameter of 125.5 nm. Nanoemulsified thyme oil exhibited quicker initial reductions of bacteria than free thyme oil in tryptic soy broth (TSB) and 2% reduced fat milk at 21 °C, due to the improved dispersibility of thyme oil. In TSB with 0.3 g/L thyme oil, it took less than 4 and 8 h for two nanoemulsions and free oil, respectively, to reduce Escherichia coli O157:H7 and Listeria monocytogenes to be below the detection limit. The emulsified thyme oil also demonstrated more significant reductions of bacteria initially (4 and 8 h) in 2% reduced fat milk than free thyme oil. Especially, with 4 g/L thyme oil, the nanoemulsion prepared with Combination A reduced L. monocytogenes to be below the detection limit after 72 h, while the free thyme oil treatment was only bacteriostatic and the turbid nanoemulsion treatment with Combination B resulted in about 1 log CFU/mL reduction. However, E. coli O157:H7 treated with 3 g/L emulsified thyme oil and Salmonella Enteritidis treated with 4 g/L emulsified thyme oil recovered to a higher extent in milk than free thyme oil treatments. The increased concentration of emulsifiers in Combination A apparently reduced the antimicrobials available to alter bacteria membrane permeability as tested by the crystal violet assay at low antimicrobial concentrations and short time (1 h). The findings suggest that nanoemulsions can be potentially used to incorporate thyme oil for use as antimicrobial preservatives in foods. Copyright © 2015 Elsevier B.V. All rights reserved.

Preparation of Fe 3O 4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

NASA Astrophysics Data System (ADS)

Li, Xiaolong; Liu, Guoqiang; Yan, Wei; Chu, Paul K.; Yeung, Kelvin W. K.; Wu, Shuilin; Yi, Changfeng; Xu, Zushun

2012-04-01

Cationic magnetic polymer particles Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe3O4, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier.

Effectiveness of methoprene, an insect growth regulator, against malaria vectors in Fars, Iran: a field study.

PubMed

Darabi, H; Vatandoost, H; Abaei, M R; Gharibi, O; Pakbaz, F

2011-01-01

Methoprene, an insect growth regulator, was evaluated under field conditions against the main malaria vectors in the Islamic Republic of Iran. The effect of 5, 10 and 20 kg ha(-1) concentration ofmethoprene granule formulation and 100 and 200 mL ha(-1) concentration of EC formulation was measured to determine any changes in Anophelini larval abundance and IE ratio in both rice fields and artificial ponds. In artificial ponds, granular methoprene at a dose of 20 kg ha(-1) inhibited adult emergence by 77.1% after 1 day and 65.9% after 3 days. The emulsifiable concentrate formulation of methoprene at 200 mL ha(-1) inhibited adult emergence by 83.7% after 1 day and 32.2% after 3 days. In rice fields, inhibition of emergence was 44.3% at 20 kg ha(-1) granule and 35.8% for emulsifiable concentrate at 200 mL ha(-1) after 3 days. The results vary depending on the mosquito species, treatment methods, breeding places and type of formulation.

UPTAKE AND EFFECTS OF DISPERSED OIL DROPLETS AND EMULSIFIED OIL BY ESTUARINE CRUSTACEANS IN THE GULF OF MEXICO

EPA Science Inventory

The results from this project will provide information on the extent of uptake of dispersed petroleum from the seawater and uptake of emulsified oil from the sediment by blue crabs and grass shrimp of different life history stages. The primary focus of the study will be eff...

Comparative viscoelasticity studies: Corn fiber gum versus commercial polysaccharide emulsifiers in bulk and at air/liquid interfaces

USDA-ARS?s Scientific Manuscript database

A comparative study of both the bulk and air/liquid interfacial rheological responses was carried out by using four kinds of high molecular weight and highly branched polysaccharide emulsifiers, (a) corn fiber gum (CFG), (b) octenyl succinate anhydride-modified starch (OSA-s), (c) gum arabic (GA) an...

Emulsifying and foaming properties of ultraviolet-irradiated egg white protein and sodium caseinate.

PubMed

Kuan, Yau-Hoong; Bhat, Rajeev; Karim, Alias A

2011-04-27

The physicochemical and functional properties of ultraviolet (UV)-treated egg white protein (EW) and sodium caseinate (SC) were investigated. UV irradiation of the proteins was carried out for 30, 60, 90, and 120 min. However, the SC samples were subjected to extended UV irradiation for 4 and 6 h as no difference was found on the initial UV exposure time. Formol titration, SDS-PAGE, and FTIR analyses indicated that UV irradiation could induce cross-linking on proteins and led to improved emulsifying and foaming properties (P < 0.05). These results indicated that the UV-irradiated EW and SC could be used as novel emulsifier and foaming agents in broad food systems for stabilizing and foaming purposes.

Improving halva quality with dietary fibres of sesame seed coats and date pulp, enriched with emulsifier.

PubMed

Elleuch, Mohamed; Bedigian, Dorothea; Maazoun, Bouthaina; Besbes, Souhail; Blecker, Christophe; Attia, Hamadi

2014-02-15

Supplementation of halva with waste products of manufacturing, for example defatted sesame seed coats (testae) and date fibre concentrate, can improve its nutritional and organoleptic qualities. These constituents provide high fibre content and technological potential for retaining water and fat. Standard halva supplemented with date fibre concentrate, defatted sesame testae and emulsifier was evaluated for oil separation, texture and colour changes, sensory qualities and acceptability to a taste panel. Addition of both fibres with an emulsifier, improved emulsion stability and increased the hardness of halva significantly. The functional properties of sesame testae and date fibres promote nutrition and health, supplying polyphenol antioxidants and laxative benefits. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optimization of methylene blue removal by stable emulsified liquid membrane using Plackett–Burman and Box–Behnken designs of experiments

PubMed Central

Djenouhat, Meriem; Bendebane, Farida; Bahloul, Lynda; Samar, Mohamed E. H.

2018-01-01

The stability of an emulsified liquid membrane composed of Span80 as a surfactant, D2EHPA as an extractant and sulfuric acid as an internal phase was first studied according to different diluents and many operating parameters using the Plackett–Burman design of experiments. Then the removal of methylene blue from an aqueous solution has been carried out using this emulsified liquid membrane at its stability conditions. The effects of operating parameters were analysed from the Box–Behnken design of experiments. The optimization of the extraction has been realized applying the response surface methodology and the results showed that the dye extraction yielding 98.72% was achieved at optimized conditions. PMID:29515841

Haererehalobacter sp. JS1, a bioemulsifier producing halophilic bacterium isolated from Indian solar salt works.

PubMed

Birdilla Selva Donio, Mariathason; Chelladurai Karthikeyan, Subbiahanadar; Michaelbabu, Mariavincent; Uma, Ganapathi; Raja Jeya Sekar, Ramaiyan; Citarasu, Thavasimuthu

2018-05-18

Bioemulsifier (BE)-producing Haererehalobacter sp. JS1 was isolated and identified from the solar salt works in India. The BE was extracted, purified, and characterized by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Emulsification activity was performed against different oils and dye degradation potential against different dyes. The production of BE was optimized using different carbon sources (C), nitrogen sources (N), pH, and NaCl. BE screening methods revealed that, Haererehalobacter sp. JS1 was highly positive BE production. Identification by 16S rRNA sequencing and analyses was found that, the Haererehalobacter sp. JS1 was closely related to Salinicoccus halophilus and Haererehalobacter sp. The structural characterization analysis confirmed that the partially purified bioemulsifier belongs to siloxane-type. Emulsification activity (E24) revealed that the bioemulsifier significantly (p < = 0.001) emulsified the commercial oils including coconut oil, gingelly oil, olive oil, and palmolein oils. Haererehalobacter sp. JS1 also significantly (p < = 0.001) degraded the dyes such as orange MR, direct violet, cotton red, reactive yellow, nitro green, and azo dye. RSM regression co-efficient and contour plot analysis clearly indicated that the combination of pH and NaCl helped to increase BE production. Siloxane-type of BE obtained from Haererehalobacter sp. JS1 was able to emulsify different oils and commercial dyes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rheological Enhancement of Pork Myofibrillar Protein-Lipid Emulsion Composite Gels via Glucose Oxidase Oxidation/Transglutaminase Cross-Linking Pathway.

PubMed

Wang, Xu; Xiong, Youling L; Sato, Hiroaki

2017-09-27

Porcine myofibrillar protein (MP) was modified with glucose oxidase (GluOx)-iron that produces hydroxyl radicals then subjected to microbial transglutaminase (TGase) cross-linking in 0.6 M NaCl at 4 °C. The resulting aggregation and gel formation of MP were examined. The GluOx-mediated oxidation promoted the formation of both soluble and insoluble protein aggregates via disulfide bonds and occlusions of hydrophobic groups. The subsequent TGase treatment converted protein aggregates into highly cross-linked polymers. MP-lipid emulsion composite gels formed with such polymers exhibited markedly enhanced gelling capacity: up to 4.4-fold increases in gel firmness and 3.5-fold increases in gel elasticity over nontreated protein. Microstructural examination showed small oil droplets dispersed in a densely packed gel matrix when MP was oxidatively modified, and the TGase treatment further contributed to such packing. The enzymatic GluOx oxidation/TGase treatment shows promise to improve the textural properties of emulsified meat products.

Chemical composition, rheological, quality characteristics and storage stability of buns enriched with coriander and curry leaves.

PubMed

Sudha, M L; Rajeswari, G; Venkateswara Rao, G

2014-12-01

Effect of addition of normal (NL) and dehydrated (DL) curry leaves (Murraya koeniggi) and coriander leaves (Corinadrum sativum) in the ratio of 1:1 to refined wheat flour (WF) or a blend of refined wheat flour-whole wheat flour (WF-WWF, 1:1) on the rheological, nutritional, storage and quality characteristics of the buns were studied. Water absorption increased on addition of increasing levels of DL from 0 to 7.5 % to WF-WWF when compared to WF. Dough weakening was greater when DL was added to WF-WWF as seen in decrease in dough stability and abscissa at rupture values. Addition of gluten and emulsifiers improved the quality characteristics of buns prepared using either 25 % NL or 5 % DL. Storage stability of buns with DL was better. The protein, dietary fiber, iron and carotenoids in buns prepared from WF-WWF were higher. The results indicate the utilization of leaves in dehydrated form in the preparation of nutritionally improved buns.

The influence of surfactant HLB and oil/surfactant ratio on the formation and properties of self-emulsifying pellets and microemulsion reconstitution.

PubMed

Matsaridou, Irini; Barmpalexis, Panagiotis; Salis, Andrea; Nikolakakis, Ioannis

2012-12-01

Self-emulsifying oil/surfactant mixtures can be incorporated into pellets that have the advantages of the oral administration of both microemulsions and a multiple-unit dosage form. The purpose of this work was to study the effects of surfactant hydrophilic-lipophilic balance (HLB) and oil/surfactant ratio on the formation and properties of self-emulsifying microcrystalline cellulose (MCC) pellets and microemulsion reconstitution. Triglycerides (C(8)-C(10)) was the oil and Cremophor ELP and RH grades and Solutol the surfactants. Pellets were prepared by extrusion/spheronization using microemulsions with fixed oil/surfactant content but with different water proportions to optimize size and shape parameters. Microemulsion reconstitution from pellets suspended in water was evaluated by turbidimetry and light scattering size analysis, and H-bonding interactions of surfactant with MCC from FT-IR spectra. It was found that water requirements for pelletization increased linearly with increasing HLB. Crushing load decreased and deformability increased with increasing oil/surfactant ratio. Incorporation of higher HLB surfactants enhanced H-bonding and resulted in faster and more extensive disintegration of MCC as fibrils. Reconstitution was greater at high oil/surfactant ratios and the droplet size of the reconstituted microemulsions was similar to that in the wetting microemulsions. The less hydrophilic ELP with a double bond in the fatty acid showed weaker H-bonding and greater microemulsion reconstitution. Purified ELP gave greater reconstitution than the unpurified grade. Thus, the work demonstrates that the choice of type and quantity of the surfactant used in the formulation of microemulsions containing pellets has an important influence on their production and performance.

Effects of ultrasound pretreatment on the enzymatic hydrolysis of soy protein isolates and on the emulsifying properties of hydrolysates.

PubMed

Chen, Lin; Chen, Jianshe; Ren, Jiaoyan; Zhao, Mouming

2011-03-23

Soy protein isolate (SPI) was modified by ultrasound pretreatment (200 W, 400 W, 600 W) and controlled papain hydrolysis, and the emulsifying properties of SPIH (SPI hydrolysates) and USPIH (ultrasound pretreated SPIH) were investigated. Analysis of mean droplet sizes and creaming indices of emulsions formed by SPIH and USPIH showed that some USPIH had markedly improved emulsifying capability and emulsion stabilization against creaming during quiescent storage. Compared with control SPI and SPIH-0.58% degree of hydrolysis (DH), USPIH-400W-1.25% (USPIH pretreated under 400W sonication and hydrolyzed to 1.25% DH) was capable of forming a stable fine emulsion (d43=1.79 μm) at a lower concentration (3.0% w/v). A variety of physicochemical and interfacial properties of USPIH-400W products have been investigated in relation to DH and emulsifying properties. SDS-PAGE showed that ultrasound pretreatment could significantly improve the accessibility of some subunits (α-7S and A-11S) in soy proteins to papain hydrolysis, resulting in changes in DH, protein solubility (PS), surface hydrophobicity (H0), and secondary structure for USPIH-400W. Compared with control SPI and SPIH-0.58%, USPIH-400W-1.25% had a higher protein adsorption fraction (Fads) and a lower saturation surface load (Γsat), which is mainly due to its higher PS and random coil content, and may explain its markedly improved emulsifying capability. This study demonstrated that combined ultrasound pretreatment and controlled enzymatic hydrolysis could be an effective method for the functionality modification of globular proteins.

Food Emulsifier Glycerin Monostearate Increases Internal Exposure Levels of Six Priority Controlled Phthalate Esters and Exacerbates Their Male Reproductive Toxicities in Rats.

PubMed

Gao, Hai-Tao; Xu, Run; Cao, Wei-Xin; Zhou, Xu; Yan, Ye-Hui-Mei; Lu, Lingeng; Xu, Qian; Shen, Yang

2016-01-01

Human beings are inevitably exposed to ubiquitous phthalate esters (PAEs). Processed, packaged foods are popular nowadays, in which emulsifiers are frequently added as food additives. It is unclear how emulsifiers affect the bioavailability of ingested PAEs contaminants and their toxicities. The purposes of our study were to explore whether food emulsifier Glycerin Monostearate (GMS) could increase the internal exposure levels of six priority controlled PAEs and affect their reproductive toxicities when male rats are exposed to PAEs mixture (MIXPs). The male rats were exposed to MIXPs by gavage for thirty days in combination with or without given GMS. Phthalate monoesters (MPAEs), primary metabolites of PAEs, in rat urine were used as biomarkers to predict the internal exposure levels of the six PAEs, and their concentrations were determined using UPLC-MS. The reproductive toxicity was evaluated using serum testosterone levels test and histopathology of testes. Results showed that compared to PAEs exposure alone, the internal exposure levels of PAEs increased by 30%-49% in the presence of GMS. PAEs exposure led to the reduction of testosterone level by 23.4%-42.1% in the presence and absence of GMS, respectively, compared to the baseline. Testosterone levels in MIXPs+GMS and DEHP+GMS group were decreased by 9.1% and 13.6%, respectively, compared with MIXPs and DEHP group. Histopathology showed that injuries of testis (deciduous spermatids) were observed, and GMS exacerbated the injuries. The results indicated food emulsifiers chronically taken up might increase safety risks of food PAEs contaminants.

HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF AN EMULSIFIED HEAVY FUEL OIL IN A FIRETUBE BOILER

EPA Science Inventory

The report gives results of measuring emissions of hazardous air pollutants (HAPs) from the combustion flue gases of a No. 6 fuel oil, both with and without an emulsifying agent, in a 2.5 million Btu/hr (732 kW) firetube boiler with the purpose of determining the impacts of the e...

Ultrasound Assisted Synthesis of Hydroxylated Soybean Lecithin from Crude Soybean Lecithin as an Emulsifier.

PubMed

Chiplunkar, Pranali P; Pratap, Amit P

2017-10-01

Soybean lecithin is a by-product obtained during degumming step of crude soybean oil refining. Crude soybean lecithin (CSL) contains major amount of phospholipids (PLs) along with minor amount of acylglycerols, bioactive components, etc. Due to presence of PLs, CSL can be used as an emulsifier. Crude soybean lecithin (CSL) was utilized to synthesize hydroxylated soybean lecithin (HSL) by hydroxylation using hydrogen peroxide and catalytic amount of lactic acid to enhance the hydrophilicity and emulsifying properties of CSL. To reduce the reaction time and to increase rate of reaction, HSL was synthesized under ultrasound irradiation. The effect of different operating parameters such as lactic acid, hydrogen peroxide, temperature, ultrasonic power and duty cycle in synthesis of HSL were studied and optimized. The surface tension (SFT), interfacial tension (IFT) and the critical micelle concentration (CMC) of the HSL (26.11 mN/m, 2.67 mN/m, 112 mg/L) were compared to CSL (37.53 mN/m, 6.22 mN/m, 291 mg/L) respectively. The HSL has better emulsion stability and low foaming characteristics as compared to CSL. Therefore, the product as an effective emulsifier can be used in food, pharmacy, lubricant, cosmetics, etc.

Characterization of industrial wastes as raw materials for Emulsified Modified Bitumen (EMB) formulation

NASA Astrophysics Data System (ADS)

Najib Razali, Mohd; Isa, Syarifah Nur Ezatie Mohd; Salehan, Noor Adilah Md; Musa, Musfafikri; Aziz, Mohd Aizudin Abd; Nour, Abdurahman Hamid; Yunus, Rosli Mohd

2018-04-01

This study was conducted to characterize industrial wastes for formulation of emulsified modified bitumen (EMB) in relation to their physical characteristic and elemental composition. This analysis will give information either raw materials from industrial wastes can be used for EMB formulation. Bitumen is produced from crude oil that is extracted from the ground which categorizes the crude oil as one of the non-renewable form of product. A vast environmental problem issues arises in Malaysia cause by the excessive manufacturing activity that lead to a miss-management of industrial waste has leads to the used of industrial waste in the EMB formulation. Industrial waste such as polystyrene, polyethylene and used automotive oil can be used as alternative to formulate bitumen. Then a suitable emulsifier needs to be added to produce the final product which is EMB. The emulsifier will yield a charge depends on its properties to bind the oily bitumen with water. Physical characteristic studies were performed by thermogravimetric Analysis (TGA), differential scanning calorimetry (DSC), flash point test, density rest and moisture content test. Fourier Transform Infrared Spectroscopy (FTIR) analysis was measured to determine the material’s molecular composition and structure.

Foaming and emulsifying properties of porcine red cell protein concentrate.

PubMed

Salvador, P; Saguer, E; Parés, D; Carretero, C; Toldrà, M

2010-08-01

This work focuses on studying the effects of pH (7.0 and 4.5) and protein concentration on the foaming and emulsifying properties of fresh (F) and spray-dried (SD) porcine red cell protein (RCP) concentrates in order to evaluate the proper use of this blood protein as a functional food ingredient. Also, protein solubility is measured through the pH range from 3.0 to 8.0. In each case, all concentrates show a high solubility, although this is significantly affected by pH. Spray drying slightly reduces the solubility at mild acid and neutral conditions. The foaming capacity is found to be dependent on pH as well as on the drying treatment. SD-RCP concentrates show better foaming capacity than F-RCP. The minimum protein concentration required to attain the highest foaming capacity is found under acid pH for the spray-dried concentrates. Although F-RCP shows low foam stability at acid and neutral pH, spray drying and protein content enhance the stability of foams. Emulsifying properties show dependence on pH as well as on protein content. Furthermore, spray drying affects the emulsifying properties but in different ways, depending on pH and protein concentration.

Citral stabilization and characterization of nanoemulsions stabilized by a mixture of gelatin and Tween 20 in an acidic system.

PubMed

Tian, Huaixiang; Li, Danfeng; Xu, Ting; Hu, Jing; Rong, Yuzhi; Zhao, Bo

2017-07-01

Citral is one of the most important flavor compounds in fresh juice and lemon oil. Unfortunately, citral is chemically unstable and degrades over time in aqueous solutions. Here, citral nanoemulsions including a mixture of gelatin and Tween 20 as emulsifiers were produced in an effort to maintain the stability of citral in an acidic system. The mean droplet size and polydispersity index of the citral nanoemulsion were 467.83 nm and 0.259 respectively when the mass ratio of gelatin/Tween 20 was 3:1 and the total emulsifier concentration of the emulsion system was 10 g kg -1 . The citral nanoemulsion remained stable during storage for 14 days at 30 °C. Therefore this nanoemulsion system effectively protected citral from degradation and decreased the formation of off-flavor compounds (e.g. p-cymene, p-cresol and p-methylacetophenone) relative to a single emulsifier. The mixture of gelatin and Tween 20 enhanced the stability of citral under acidic conditions and could be used as an effective emulsifier to protect citral from degradation under acidic environments in the food industry. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Identification of outer membrane proteins with emulsifying activity by prediction of beta-barrel regions.

PubMed

Walzer, Gil; Rosenberg, Eugene; Ron, Eliora Z

2009-01-01

Microbial bioemulsifiers are secreted by many bacteria and are important for bacterial interactions with hydrophobic substrates or nutrients and for a variety of biotechnological applications. We have recently shown that the OmpA protein in several members of the Acinetobacter family has emulsifying properties. These properties of OmpA depend on the amino acid composition of four putative extra-membrane loops, which in various strains of Acinetobacter, but not in E. coli, are highly hydrophobic. As many Acinetobacter strains can utilize hydrophobic carbon sources, such as oil, the emulsifying activity of their OmpA may be important for the utilization and uptake of hydrocarbons. We assumed that if outer membrane proteins with emulsifying activity are physiologically important, they may exist in additional oil degrading bacteria. In order to identify such proteins, it was necessary to obtain bioinformatics-based predictions for hydrophobic extra-membrane loops. Here we describe a method for using protein sequence data for predicting the hydrophobic properties of the extra-membrane loops of outer membrane proteins. The feasibility of this method is demonstrated by its use to identify a new microbial bioemulsifier - OprG - an outer membrane protein of the oil degrading Pseudomonas putida KT2440.

Effect of W/O Emulsion Fuel Properties on Spray Combustion

NASA Astrophysics Data System (ADS)

Ida, Tamio; Fuchihata, Manabu; Takeda, Shuuco

This study proposes a realizable technology for an emulsion combustion method that can reduce environmental loading. This paper discusses the effect on spray combustion for W/O emulsion fuel properties with an added agent, and the ratio between water and emulsifier added to a liquid fuel. The addition of water or emulsifier to a liquid fuel affected the spray combustion by causing micro-explosions in the flame due to geometric changes in the sprayed flame and changes to the temperature distribution. Experimental results revealed that the flame length shortened by almost 40% upon the addition of the water. Furthermore, it was found that water was effective in enhancing combustion due to its promoting micro-explosions. Results also showed that when the emulsifier was added to the spray flame, the additive burned in the flame's wake, producing a bright red flame. The flame length was observed to be long as a result. The micro-explosion phenomenon, caused by emulsifier dosage differences, was observed using time-dependent images at a generated frequency and an explosion scale with a high-speed photography method. Results indicated that the micro-explosion phenomenon in the W/O emulsion combustion method effectively promoted the combustion reaction and suppressed soot formation.

Effects of rice bran on sensory and physico-chemical properties of emulsified pork meatballs.

PubMed

Huang, S C; Shiau, C Y; Liu, T E; Chu, C L; Hwang, D F

2005-08-01

Four kinds of bran, which are milled from important rice cultivators in Taiwan, have high contents of dietary fiber, fat and protein. The use of rice bran in Kung-wan, an emulsified pork meatball, was investigated. It was found that protein and fat contents, and white index of meatballs decreased as the amount of bran increased. A texture profile analysis (TPA) also indicated the hardness, gumminess and chewiness of the Kung-wan decreased. The sensory scores of taste, texture and overall acceptability of meatballs with less than 10% added bran showed no significant difference from those for meatballs without bran. However, the added amount of 15% enriched meatballs resulted in inferior sensory scores. The bran's particle size profoundly affected the sensory and physico-chemical properties of the meat products. Meatballs enriched with smaller bran particles possessed higher TPA indices and sensory scores than those added with larger ones. No significant differences in proximate composition, cooking yield, color and sensory quality were found among emulsified meatballs enriched with four different kinds of bran. Conclusively, the suitable amount of rice bran that should be added to emulsified pork meatballs was less than 10% and a smaller particle size would result in better quality.

Acacia gum as modifier of thermal stability, solubility and emulsifying properties of α-lactalbumin.

PubMed

de Oliveira, Fabíola Cristina; Dos Reis Coimbra, Jane Sélia; de Oliveira, Eduardo Basílio; Rodrigues, Marina Quadrio Raposo Branco; Sabioni, Rachel Campos; de Souza, Bartolomeu Warlene Silva; Santos, Igor José Boggione

2015-03-30

Protein-polysaccharide conjugates often display improved techno-functional properties when compared to their individual involved biomolecules. α-Lactalbumin:acacia gum (α-la:AG) conjugates were prepared via Maillard reaction by the dry-heating method. Conjugate formation was confirmed using results of absorbance, o-phthalaldehyde test, sodium dodecyl sulfate-polyacrilamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography. Techno-functional properties (emulsifying characteristics, solubility, and thermal stability) were evaluated for α-la, α-la/AG mixtures and α-la:AG conjugates. Conjugate thermal stability was improved compared to pure α-la treated at the same conditions of conjugate formation. Response surface methodology was used to establish models to predict solubility and emulsifying activity as functions of the salt concentration, pH and reaction time. α-la:AG conjugate solubility is affected in a complex manner by the three factors analyzed. Emulsifying activity index (EAI) of α-la is significantly affected by pH, while the α-la:AG EAI is affected by the three analyzed factors. Both solubility and EAI are maximized with pH 8.0, NaCl concentration of 0.3 mol L(-1) and two days of Maillard reaction. Copyright © 2014 Elsevier Ltd. All rights reserved.

Removal of Emulsified Oil from Water by Fruiting Bodies of Macro-Fungus (Auricularia polytricha)

PubMed Central

Yang, Xunan; Guo, Mengting; Wu, Yinghai; Wu, Qunhe; Zhang, Renduo

2014-01-01

The aim of this study was to investigate the feasibility of utilizing the fruiting bodies of a jelly macro-fungus Auricularia polytricha as adsorbents to remove emulsified oil from water. The effects of several factors, including temperature, initial pH, agitation speed, and adsorbent dosage, were taken into account. Results showed that the optimized conditions for adsorption of A. polytricha were a temperature of 35°C, pH of 7.5, and agitation speed of 100 rpm. The adsorption kinetics were characterized by the pseudo-first order model, which showed the adsorption to be a fast physical process. The Langmuir-Freundlich isotherm described the adsorption very well and predicted the maximum adsorption capacity of 398 mg g−1, under optimized conditions. As illustrated by scanning electron micrographs, the oil particles were adsorbed onto the hairs covering the bottom surface and could be desorbed by normal temperature volatilization. The material could be used as an emulsified oil adsorbent at least three times, retaining more than 95% of the maximum adsorption capacity. The results demonstrated that the fruiting bodies of A. polytricha can be a useful adsorbent to remove emulsified oil from water. PMID:24743498

Characterization of individual complex particles in urban atmospheric environment

NASA Astrophysics Data System (ADS)

Suzuki, K.; Takii, T.; Tomiyasu, B.; Nihei, Y.

2006-07-01

The origins of carrier particles of complex particles (iron-rich particles) collected from the urban atmospheric environment near to road traffic and a railroad were investigated from the detailed surface information using FE-SEM/EDS and TOF-SIMS analyses. From the FE-SEM/EDS analyses, the iron-rich particles were classified into two typical types (spherical type and non-spherical type). From the TOF-SIMS measurements, the characteristic secondary ions of spherical type of iron-rich particles were 23Na + and 39K +. The minor components of non-spherical type were Al, Ca and Ba. On the other hand, we carried out TOF-SIMS measurement to materials of rail origin and brake origin. From the comparison of these spectra pattern, it seemed that the spherical type of iron-rich particles was emitted from the rail origin. We concluded that the origin of non-spherical type of iron-rich particles were brake pad of vehicles.

A High Serum Iron Level Causes Mouse Retinal Iron Accumulation Despite an Intact Blood-Retinal Barrier

PubMed Central

Zhao, Liangliang; Li, Yafeng; Song, Delu; Song, Ying; Theurl, Milan; Wang, Chenguang; Cwanger, Alyssa; Su, Guanfang; Dunaief, Joshua L.

2015-01-01

The retina can be shielded by the blood-retinal barrier. Because photoreceptors are damaged by excess iron, it is important to understand whether the blood-retinal barrier protects against high serum iron levels. Bone morphogenic protein 6 (Bmp6) knockout mice have serum iron overload. Herein, we tested whether the previously documented retinal iron accumulation in Bmp6 knockout mice might result from the high serum iron levels or, alternatively, low levels of retinal hepcidin, an iron regulatory hormone whose transcription can be up-regulated by Bmp6. Furthermore, to determine whether increases in serum iron can elevate retinal iron levels, we i.v. injected iron into wild-type mice. Retinas were analyzed by real-time quantitative PCR and immunofluorescence to assess the levels of iron-regulated genes/proteins and oxidative stress. Retinal hepcidin mRNA levels in Bmp6 knockout retinas were the same as, or greater than, those in age-matched wild-type retinas, indicating that Bmp6 knockout does not cause retinal hepcidin deficiency. Changes in mRNA levels of L ferritin and transferrin receptor indicated increased retinal iron levels in i.v. iron-injected wild-type mice. Oxidative stress markers were elevated in photoreceptors of mice receiving i.v. iron. These findings suggest that elevated serum iron levels can overwhelm local retinal iron regulatory mechanisms. PMID:25174877

Grape seed and apple tannins: emulsifying and antioxidant properties.

PubMed

Figueroa-Espinoza, Maria Cruz; Zafimahova, Andrea; Alvarado, Pedro G Maldonado; Dubreucq, Eric; Poncet-Legrand, Céline

2015-07-01

Tannins are natural antioxidants found in plant-based foods and beverages, whose amphiphilic nature could be useful to both stabilize emulsions and protect unsaturated lipids from oxidation. In this paper, the use of tannins as antioxidant emulsifiers was studied. The main parameters influencing the stability of emulsions (i.e. tannins structure and concentration, aqueous phase pH, and ionic strength) were identified and optimized. Oil in water emulsions stabilized with tannins were compared with those stabilized with two commercial emulsifying agents, poly(vinyl alcohol) (PVA) and polyoxyethylene hydrogenated castor oil. In optimized conditions, the condensed tannins allowed to obtain a stability equivalent to that of PVA. Tannins presented good antioxidant activity in oil in water emulsion, as measured by the conjugated autoxidizable triene (CAT) assay. Copyright © 2015 Elsevier Ltd. All rights reserved.

Food additives

PubMed Central

Spencer, Michael

1974-01-01

Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

Mitigation of NOx and smoke emissions in a diesel engine using novel emulsified lemon peel oil biofuel.

PubMed

Bragadeshwaran, Ashok; Kasianantham, Nanthagopal; Balusamy, Saravanan; Muniappan, SenthilKumar; Reddy, Dandu Madhu Sudan; Subhash, Randive Vishal; Pravin, Nashte Adarsh; Subbarao, Rayapati

2018-06-25

Lemon peel oil (LPO) is considered to be a viable alternative fuel for diesel engine applications due to its wider availability, renewable nature, easy extraction process, almost equivalent calorific value as neat diesel, and low viscosity. The present work aims to investigate the effect of novel emulsified LPO in a diesel engine in order to reduce the NOx emission without compromising the engine performance. A new ionic surfactant is introduced in the present study, namely methyl-dihydroxy propyl imidazolium chloride due to its higher hydrophilic-lipophilic balance value which helps to prepare stable water in oil emulsion. Also, Span 80 has been selected as another suitable surfactant for water in oil emulsion. Four emulsified fuel samples have been prepared using LPO, water, and different concentrations of surfactants. All the fuel samples are tested for their stability through gravitational technique for 7 days. Among the emulsified samples, 92% LPO + 5% water + 2% Span 80 + 1% methyl-dihydroxy propyl imidazolium chloride by volume (LPOE2) and 93.5% LPO + 5% water + 1.5% surfactant Span 80 by volume (LPOE4) have showed better stability when compared to other emulsion fuel samples. It is also revealed that the stability of LPO emulsion is improved by the addition of two emulsions. The experimental results showed that the brake thermal efficiency of LPO emulsion is reduced to 29.87 from 34.58% of pure LPO at full load condition. Oxides of nitrogen emission and smoke emission are reduced by 21-32 and 6-15% for the LPO emulsion samples compared to pure LPO. Moreover, the diesel engine operation with emulsified form of LPO increases the HC emission about 0.1 g/kWh for LPOE4 and 0.15 g/kWh for LPOE2 fuels from 0.053 g/kW for pure LPO at maximum power output condition. The reformulation of LPO into emulsified form increases the CO emission by 25-53% compared to pure LPO. Moreover, the reformulation of LPO into emulsions has resulted in lower cylinder pressure and heat release rate compared to pure LPO and diesel fuels.

HFE mRNA expression is responsive to intracellular and extracellular iron loading: short communication.

PubMed

Mehta, Kosha J; Farnaud, Sebastien; Patel, Vinood B

2017-10-01

In liver hepatocytes, the HFE gene regulates cellular and systemic iron homeostasis by modulating cellular iron-uptake and producing the iron-hormone hepcidin in response to systemic iron elevation. However, the mechanism of iron-sensing in hepatocytes remain enigmatic. Therefore, to study the effect of iron on HFE and hepcidin (HAMP) expressions under distinct extracellular and intracellular iron-loading, we examined the effect of holotransferrin treatment (1, 2, 5 and 8 g/L for 6 h) on intracellular iron levels, and mRNA expressions of HFE and HAMP in wild-type HepG2 and previously characterized iron-loaded recombinant-TfR1 HepG2 cells. Gene expression was analyzed by real-time PCR and intracellular iron was measured by ferrozine assay. Data showed that in the wild-type cells, where intracellular iron content remained unchanged, HFE expression remained unaltered at low holotransferrin treatments but was upregulated upon 5 g/L (p < 0.04) and 8 g/L (p = 0.05) treatments. HAMP expression showed alternating elevations and increased upon 1 g/L (p < 0.05) and 5 g/L (p < 0.05). However, in the recombinant cells that showed higher intracellular iron levels than wild-type cells, HFE and HAMP expressions were elevated only at low 1 g/L treatment (p < 0.03) and were repressed at 2 g/L treatment (p < 0.03). Under holotransferrin-untreated conditions, the iron-loaded recombinant cells showed higher expressions of HFE (p < 0.03) and HAMP (p = 0.05) than wild-type cells. HFE mRNA was independently elevated by extracellular and intracellular iron-excess. Thus, it may be involved in sensing both, extracellular and intracellular iron. Repression of HAMP expression under simultaneous intracellular and extracellular iron-loading resembles non-hereditary iron-excess pathologies.

The F'derik-Zouerate iron district: Mesoarchean and Paleoproterozoic iron formation of the Tiris Complex, Islamic Republic of Mauritania

USGS Publications Warehouse

Taylor, Cliff D.; Finn, Carol A.; Anderson, Eric D.; Bradley, Dwight C.; Joud, Mohamed; Taleb Mohamed, Ahmed; Horton, John D.; Johnson, Craig A.; Bouabdellah, Mohammed; Slack, John F.

2016-01-01

High-grade hematitic iron ores (of HIF, containing 60-65 wt%Fe) have been mined in Mauritania since 1952 from Superior-type iron deposits of the F'derik-Zouerate district.  Depletion of the high-grade ores in recent years has resulted in new exploration projects focused on lower-grade magnetite ores occurring in Algoma-type banded iron formation (of BIF, containing ca. 35 wt% Fe).  Mauritania is the seventeenth largest iron producer in the world and currently has about 1.1 Gt of crude iron ore reserves. 

Relative toxicity of lead and selected substitute shot types to game farm mallards

USGS Publications Warehouse

Irby, H.D.; Locke, L.N.; Bagley, George E.

1967-01-01

The acute toxicity of lead, three types of plastic-coated lead, two lead-magnesium alloys, iron, copper, zinc-coated iron, and molybdenum-coated iron shot were tested in year-old male game farm mallards. Mallards (Anus platyrhynchos) were fed eight number 6 shot of each type and observed for a period of 60 days. Ducks used totaled 230 and most shot types were tested in three replicates of 8 ducks each. Mortality and losses of body weight were the criteria used for judging toxicity. Three types of plastic-coated lead shot were as toxic (93 percent) as the commercial lead shot (96 percent). The average mortality in mallards fed lead-magnesium alloy shot was less (58 percent) than that occurring in birds fed commercial lead shot. Mortality among mallards fed iron, copper, zinc-coated iron or molybdenum-coated iron shot was significantly less than in birds fed lead shot, and was not significantly greater than the conrtols.

Delivery of phytochemical thymoquinone using molecular micelle modified poly(D, L lactide-co-glycolide) (PLGA) nanoparticles

NASA Astrophysics Data System (ADS)

Ganea, Gabriela M.; Fakayode, Sayo O.; Losso, Jack N.; van Nostrum, Cornelus F.; Sabliov, Cristina M.; Warner, Isiah M.

2010-07-01

Continuous efforts have been made in the development of potent benzoquinone-based anticancer drugs aiming for improved water solubility and reduced adverse reactions. Thymoquinone is a liposoluble benzoquinone-based phytochemical that has been shown to have remarkable antioxidant and anticancer activities. In the study reported here, thymoquinone-loaded PLGA nanoparticles were synthesized and evaluated for physico-chemical, antioxidant and anticancer properties. The nanoparticles were synthesized by an emulsion solvent evaporation method using anionic molecular micelles as emulsifiers. The system was optimized for maximum entrapment efficiency using a Box-Behnken experimental design. Optimum conditions were found for 100 mg PLGA, 15 mg TQ and 0.5% w/v poly(sodium N-undecylenyl-glycinate) (poly-SUG). In addition, other structurally related molecular micelles such as poly(sodium N-heptenyl-glycinate) (poly-SHG), poly(sodium N-undecylenyl-leucinate) (poly-SUL), and poly(sodium N-undecylenyl-valinate) (poly-SUV) were also examined as emulsifiers. All investigated molecular micelles provided excellent emulsifier properties, leading to maximum optimized TQ entrapment efficiency, and monodispersed particle sizes below 200 nm. The release of TQ from molecular micelle modified nanoparticles was investigated by dialysis and reached lower levels than the free drug. The antioxidant activity of TQ-loaded nanoparticles, indicated by IC50 (mg ml - 1 TQ for 50% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity), was highest for poly-SUV emulsified nanoparticles (0.030 ± 0.002 mg ml - 1) as compared to free TQ. In addition, it was observed that TQ-loaded nanoparticles emulsified with poly-SUV were more effective than free TQ against MDA-MB-231 cancer cell growth inhibition, presenting a cell viability of 16.0 ± 5.6% after 96 h.

Characterization of E 471 food emulsifiers by high-performance thin-layer chromatography-fluorescence detection.

PubMed

Oellig, Claudia; Brändle, Klara; Schwack, Wolfgang

2018-07-13

Mono- and diacylglycerol (MAG and DAG) emulsifiers, also known as food additive E 471, are widely used to adjust techno-functional properties in various foods. Besides MAGs and DAGs, E 471 emulsifiers additionally comprise different amounts of triacylglycerols (TAGs) and free fatty acids (FFAs). MAGs, DAGs, TAGs and FFAs are generally determined by high-performance liquid chromatography (HPLC) or gas chromatography (GC) coupled to mass selective detection, analyzing the individual representatives of the lipid classes. In this work we present a rapid and sensitive method for the determination of MAGs, DAGs, TAGs and FFAs in E 471 emulsifiers by high-performance thin-layer chromatography with fluorescence detection (HPTLC-FLD), including a response factor system for quantitation. Samples were simply dissolved and diluted with t-butyl methyl ether before a two-fold development was performed on primuline pre-impregnated LiChrospher silica gel plates with diethyl ether and n-pentane/n-hexane/diethyl ether (52:20:28, v/v/v) as the mobile phases to 18 and 75 mm, respectively. For quantitation, the plate was scanned in the fluorescence mode at UV 366/>400 nm, when the cumulative signal for each lipid class was used. Calibration was done with 1,2-distearin and amounts of lipid classes were calculated with response factors and expressed as monostearin, distearin, tristearin and stearic acid. Limits of detection and quantitation were 1 and 4 ng/zone, respectively, for 1,2-distearin. Thus, the HPTLC-FLD approach represents a simple, rapid and convenient screening alternative to HPLC and GC analysis of the individual compounds. Visual detection additionally enables an easy characterization and the direct comparison of emulsifiers through the lipid class pattern, when utilized as a fingerprint. Copyright © 2018 Elsevier B.V. All rights reserved.

The B-type channel is a major route for iron entry into the ferroxidase center and central cavity of bacterioferritin

DOE PAGES

Wong, Steve G.; Grigg, Jason C.; Le Brun, Nick E.; ...

2014-12-15

Bacterioferritin is a bacterial iron storage and detoxification protein that is capable of forming a ferric oxyhydroxide mineral core within its central cavity. To do this, iron must traverse the bacterioferritin protein shell, which is expected to occur through one or more of the channels through the shell identified by structural studies. The size and negative electrostatic potential of the 24 B-type channels suggest that they could provide a route for iron into bacterioferritin. Residues at the B-type channel (Asn-34, Glu-66, Asp-132, and Asp-139) of E. coli bacterioferritin were substituted to determine if they are important for iron core formation.more » A significant decrease in the rates of initial oxidation of Fe(II) at the ferroxidase center and subsequent iron mineralization was observed for the D132F variant. The crystal structure of this variant shows that substitution of residue 132 with phenylalanine caused a steric blockage of the B-type channel and no other material structural perturbation. Here, we conclude that the B-type channel is a major route for iron entry into both the ferroxidase center and the iron storage cavity of bacterioferritin.« less

COST AND PERFORMANCE REPORT: INNOVATIVE ACOUSTIC SENSOR TECHNOLOGIES FOR LEAK DETECTION IN CHALLENGING PIPE TYPES

DTIC Science & Technology

2016-12-30

Operational Variable LeakFinderRT Equipment Logistics Portable Case Pipe Material Pit Cast Iron, Spun Cast Iron, Steel , Ductile Iron, Asbestos Cement ...AND ACRONYMS AC asbestos cement AMI advanced metering infrastructure AWWA American Water Works Association CI cast iron DI ductile iron DoD...assessing their ability to detect and accurately locate leaks in challenging pipe types such as polyvinyl chloride (PVC), asbestos cement (AC), and

Conching Chocolate

NASA Astrophysics Data System (ADS)

Hunter, Gary L.; Chaikin, Paul; Blanco, Elena; Poon, Wilson

2014-03-01

``Conching'' is an intermediate step in the processing of chocolate where hydrophilic solid particles, such as sugar and milk proteins, are aggressively mixed into a fatty, fluid phase containing emulsifier, e.g. molten cocoa butter with lecithin. During conching, the system evolves from a fine powder to a coarser granulated material and ultimately into a thick cohesive paste. Our goal is to better understand the evolution of chocolate during conching and the transition from an effectively dry to a wet or immersed granular material. In particular, we focus on how mixing times change in response to variations in solid particle volume fractions and emulsifier concentration. As a function of volume fraction, mixing times are well-described by a conventional form that diverges at a finite volume fraction. Furthermore, mixing times can be collapsed onto a universal curve as a function of mixing speed and emulsifier concentration.

Females Are Protected From Iron-Overload Cardiomyopathy Independent of Iron Metabolism: Key Role of Oxidative Stress.

PubMed

Das, Subhash K; Patel, Vaibhav B; Basu, Ratnadeep; Wang, Wang; DesAulniers, Jessica; Kassiri, Zamaneh; Oudit, Gavin Y

2017-01-23

Sex-related differences in cardiac function and iron metabolism exist in humans and experimental animals. Male patients and preclinical animal models are more susceptible to cardiomyopathies and heart failure. However, whether similar differences are seen in iron-overload cardiomyopathy is poorly understood. Male and female wild-type and hemojuvelin-null mice were injected and fed with a high-iron diet, respectively, to develop secondary iron overload and genetic hemochromatosis. Female mice were completely protected from iron-overload cardiomyopathy, whereas iron overload resulted in marked diastolic dysfunction in male iron-overloaded mice based on echocardiographic and invasive pressure-volume analyses. Female mice demonstrated a marked suppression of iron-mediated oxidative stress and a lack of myocardial fibrosis despite an equivalent degree of myocardial iron deposition. Ovariectomized female mice with iron overload exhibited essential pathophysiological features of iron-overload cardiomyopathy showing distinct diastolic and systolic dysfunction, severe myocardial fibrosis, increased myocardial oxidative stress, and increased expression of cardiac disease markers. Ovariectomy prevented iron-induced upregulation of ferritin, decreased myocardial SERCA2a levels, and increased NCX1 levels. 17β-Estradiol therapy rescued the iron-overload cardiomyopathy in male wild-type mice. The responses in wild-type and hemojuvelin-null female mice were remarkably similar, highlighting a conserved mechanism of sex-dependent protection from iron-overload-mediated cardiac injury. Male and female mice respond differently to iron-overload-mediated effects on heart structure and function, and females are markedly protected from iron-overload cardiomyopathy. Ovariectomy in female mice exacerbated iron-induced myocardial injury and precipitated severe cardiac dysfunction during iron-overload conditions, whereas 17β-estradiol therapy was protective in male iron-overloaded mice. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Immobilization of iron oxide nanoparticles within alginate nanogels for enhanced MR imaging applications.

PubMed

Sun, Wenjie; Yang, Jia; Zhu, Jianzhi; Zhou, Yiwei; Li, Jingchao; Zhu, Xiaoyue; Shen, Mingwu; Zhang, Guixiang; Shi, Xiangyang

2016-10-20

We report the design of iron oxide (Fe3O4) nanoparticle (NP)-immobilized alginate (AG) nanogels (NGs) as a novel contrast agent for enhanced magnetic resonance (MR) imaging applications. In this study, an aqueous solution of AG activated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride was double emulsified to form NGs, followed by in situ cross-linking with polyethyleneimine (PEI)-coated Fe3O4 NPs (PEI-Fe3O4 NPs). The resultant Fe3O4 NP-immobilized AG NGs (AG/PEI-Fe3O4 NGs) were characterized via different techniques. Our results reveal that the hybrid NGs with a size of 186.1 ± 33.1 nm are water dispersible, colloidally stable, and cytocompatible in the given concentration range. Importantly, these NGs have a high r2 relaxivity (170.87 mM(-1) s(-1)) due to the high loading of Fe3O4 NPs within the NGs, and can be more significantly uptaken by cancer cells when compared with carboxylated Fe3O4 NPs. The formed AG/PEI-Fe3O4 NGs are able to be used as an effective contrast agent for the MR imaging of cancer cells in vitro and the xenografted tumor model in vivo after intravenous injection. The developed AG/PEI-Fe3O4 NGs may hold great promise for use as a novel contrast agent for the enhanced MR imaging of different biological systems.

Effect of antioxidant properties of lecithin emulsifier on oxidative stability of encapsulated bioactive compounds.

PubMed

Pan, Yuanjie; Tikekar, Rohan V; Nitin, N

2013-06-25

Oxidation of encapsulated bioactive compounds in emulsions is one of the key challenges that limit shelf life of emulsion containing products. Oxidation in these emulsions is triggered by permeation of free radicals generated at the emulsion interface. The objective of this study was to evaluate the role of antioxidant properties of common emulsifiers (lecithin and Tween 20) in reducing permeation of free radicals across the emulsion interface. Radical permeation rates were correlated with oxidative stability of a model bioactive compound (curcumin) encapsulated in these emulsions. Rate of permeation of peroxyl radicals from the aqueous phase to the oil phase of emulsion was inversely proportional to the antioxidant properties of emulsifiers. The rate of radical permeation was significantly higher (p<0.05) for emulsions stabilized using Tween 20 and oxidized lecithin compared to native lecithin that showed higher antioxidant activity. Free radical permeation rate correlated with stability of curcumin in emulsions and was significantly higher (p<0.05) in lecithin stabilized emulsions as compared to Tween 20 emulsions. Overall, this study demonstrates that antioxidant activity of emulsifiers significantly influences permeation of free radicals across the emulsion interface and the rate of oxidation of bioactive encapsulant. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis of pH-sensitive and recyclable magnetic nanoparticles for efficient separation of emulsified oil from aqueous environments

NASA Astrophysics Data System (ADS)

Lü, Ting; Zhang, Shuang; Qi, Dongming; Zhang, Dong; Vance, George F.; Zhao, Hongting

2017-02-01

Emulsified oil wastewaters, arisen from oil industry and oil spill accidents, cause severe environmental and ecological problems. In this study, a series of pH-sensitive magnetic nanomaterials (MNPs) were synthesized and characterized for their evaluation in separation of emulsified oil from aqueous environments. A coprecipitation method was used to produce Fe3O4 magnetic nanoparticles that were coated in a 2-step process with first silica to form a surface for anchoring an (3-aminopropyl)triethoxysilane (APTES) molecular layer. Detailed studies were conducted on effects of MNPs dosage, APTES anchoring density (DA) and pH on oil-water separation performance of the synthetic MNPs. Results showed that, under both acidic and neutral conditions, MNPs with high DA exhibited enhanced oil-water separation performance, while under alkaline condition, the oil-water separation process was minimal. Alkaline conditions allowed the MNPs to be recycled up to 9 cycles without showing any significant decrease in oil-water separation efficiency. An examination of the oil-water separation mechanism found that electrostatic interaction and interfacial activity both played important roles in oil-water separation. In conclusion, pH-sensitive MNPs can be easily synthesized and recycled, providing a promising, cost-effective and environmentally-friendly process for the efficient treatment of emulsified oil wastewater.

Controlled tissue emulsification produced by high intensity focused ultrasound shock waves and millisecond boiling

PubMed Central

Khokhlova, Tatiana D.; Canney, Michael S.; Khokhlova, Vera A.; Sapozhnikov, Oleg A.; Crum, Lawrence A.; Bailey, Michael R.

2011-01-01

In high intensity focused ultrasound (HIFU) applications, tissue may be thermally necrosed by heating, emulsified by cavitation, or, as was recently discovered, emulsified using repetitive millisecond boiling caused by shock wave heating. Here, this last approach was further investigated. Experiments were performed in transparent gels and ex vivo bovine heart tissue using 1, 2, and 3 MHz focused transducers and different pulsing schemes in which the pressure, duty factor, and pulse duration were varied. A previously developed derating procedure to determine in situ shock amplitudes and the time-to-boil was refined. Treatments were monitored using B-mode ultrasound. Both inertial cavitation and boiling were observed during exposures, but emulsification occurred only when shocks and boiling were present. Emulsified lesions without thermal denaturation were produced with shock amplitudes sufficient to induce boiling in less than 20 ms, duty factors of less than 0.02, and pulse lengths shorter than 30 ms. Higher duty factors or longer pulses produced varying degrees of thermal denaturation combined with mechanical emulsification. Larger lesions were obtained using lower ultrasound frequencies. The results show that shock wave heating and millisecond boiling is an effective and reliable way to emulsify tissue while monitoring the treatment with ultrasound. PMID:22088025

Synthesis and Surface Activity of Cationic Amino Acid-Based Surfactants in Aqueous Solution.

PubMed

Greber, Katarzyna E

2017-01-01

I studied the possibility of using amino acid-based surfactants as emulsifiers at the same time as preservatives. Fourteen lipopeptides were synthesized employing a solid phase peptide synthesis procedure. All compounds were designed to be positively charged from +1 to +4 and acylated with fatty acid chain-palmitic and miristic. The surface activity of the obtained lipopeptides was tested using a semi-automatic tensiometer to calculate parameters describing the behavior of lipopeptides in the air/water interface. Such parameters as CMC, surface tension at the CMC point ( σ CMC ), effectiveness ( π CMC ), and efficiency (pC20) were measured. Emulsifying properties of all lipopeptides were also examined. The studies reveal that the surface active properties of synthesized compounds strongly depend on the length of alkyl chains as well as on the composition of amino acid polar heads. The critical micelle concentration decreases with increasing alkyl chain length of lipopeptides with the same polar head. The effectiveness and efficiency decrease when the number of amino acids in the polar head increases. All lipopeptides established a very weak emulsification power and created unstable water/Miglyol 812 and water/paraffin oil emulsions. Results suggest that lipopeptides cannot be used as emulsifiers; nonetheless, it is possible to use them as auxiliary surfactants with disinfectant properties in combination with more potent emulsifiers.

Helix aspersa gelatin as an emulsifier and emulsion stabilizer: functional properties and effects on pancreatic lipolysis.

PubMed

Zarai, Zied; Balti, Rafik; Sila, Assaâd; Ben Ali, Yassine; Gargouri, Youssef

2016-01-01

Emulsions are widely used in food and pharmaceutical applications for the encapsulation, solubilization, entrapment, and controlled delivery of active ingredients. In order to fulfill the increasing demand for clean label excipients, natural polymers could be used to replace the potentially irritative synthetic surfactants used in emulsion formulation. In the present study, we have studied the properties of oil-in-water emulsions prepared with land snail gelatin (LSG) as the sole emulsifying agent, extracted and described for the first time. LSG was evaluated in terms of proximate composition, oil and water holding capacity, emulsifying and foaming properties, color and amino acid composition. Emulsions of trioctanoylglycerol (TC8) and olive oil were made at different gelatin/oil ratios and changes in droplet-size distribution were determined. The superior emulsifying properties of LSG, the susceptibility of gelatin protein emulsions increasing flocculation on storage, and the coalescence of gelatin emulsions following centrifugation were demonstrated. Furthermore, the effect of LSG on the activity of turkey pancreatic lipase (TPL) was evaluated through the pH-stat methodology with TC8 and olive oil emulsions. The LSG affected the TPL activity in a concentration-dependent way. Our results showed that LSG, comparably to gum arabic, increases the pancreatic lipase activity and improves its stability at the oil-water interface.

Anti-Fouling Double-Skinned Forward Osmosis Membrane with Zwitterionic Brush for Oily Wastewater Treatment.

PubMed

Ong, Chi Siang; Al-Anzi, Bader; Lau, Woei Jye; Goh, Pei Sean; Lai, Gwo Sung; Ismail, Ahmad Fauzi; Ong, Yue Seong

2017-07-31

Despite its attractive features for energy saving separation, the performance of forward osmosis (FO) has been restricted by internal concentration polarization and fast fouling propensity that occur in the membrane sublayer. These problems have significantly affected the membrane performance when treating highly contaminated oily wastewater. In this study, a novel double-skinned FO membrane with excellent anti-fouling properties has been developed for emulsified oil-water treatment. The double-skinned FO membrane comprises a fully porous sublayer sandwiched between a highly dense polyamide (PA) layer for salt rejection and a fairly loose dense bottom zwitterionic layer for emulsified oil particle removal. The top dense PA layer was synthesized via interfacial polymerization meanwhile the bottom layer was made up of a zwitterionic polyelectrolyte brush - (poly(3-(N-2-methacryloxyethyl-N,N-dimethyl) ammonatopropanesultone), abbreviated as PMAPS layer. The resultant double-skinned membrane exhibited a high water flux of 13.7 ± 0.3 L/m 2 .h and reverse salt transport of 1.6 ± 0.2 g/m 2 .h under FO mode using 2 M NaCl as the draw solution and emulsified oily solution as the feed. The double-skinned membrane outperforms the single-skinned membrane with much lower fouling propensity for emulsified oil-water separation.

[Optimization of formulations for dietetic pastry products].

PubMed

Villarroel, M; Uquiche, E; Brito, G; Cancino, M

2000-03-01

Optimized formulations of dietetic pastry products such as cake and sponge cake premixes were formulated using the surface response methodology. % Emulsifier agent and baking time were the selected independent variables for cake, as well as % emulsifier agent % chlorinated flour the variables selected for sponge cake. Three different level of each variable summing up thirteen experimental formulae of each product were assessed to optimize the variables that could have some influence in the sensory characteristics of these dietetic products. The total sensory quality was determined for both dietetic products using the composite scoring test and a panel of 18 trained judges. Looking at the contour graphic and considering economic aspects the best combination of variables for cake formulation was 2% emulsifier agent and 48 minutes for baking time, With respect to sponge cake, the best combination was 6% emulsifier agent and 48% chlorinated flour. Shelf life studies showed that both dietetic formulations remained stable during storage conditions of 75 days at 30 degrees C. During this period, significant differences in sensory characteristics were not found (p < 0.05). Data of peroxide values were kept under the critical value reported for detection of organoleptic rancidity. Reported values of hedonic test showed that these dietetics pastry products had good acceptability, and open up marketing opportunities for new products with potential health benefits to consumers.

Submicron Emulsions and Their Applications in Oral Delivery.

PubMed

Mundada, Veenu; Patel, Mitali; Sawant, Krutika

2016-01-01

A "submicron emulsion" is an isotropic mixture of drug, lipids, and surfactants, usually with hydrophilic cosolvents and with droplet diameters ranging from 10 to 500 nm. Submicron emulsions are of increasing interest in medicine due to their kinetic stability, high solubilizing capacity, and tiny globule size. Because of these properties, they have been applied in various fields, such as personal care, cosmetics, health care, pharmaceuticals, and agrochemicals. Submicron emulsions are by far the most advanced nanoparticulate systems for the systemic delivery of biologically active agents for controlled drug delivery and targeting. They are designed mainly for pharmaceutical formulations suitable for various routes of administration like parenteral, ocular, transdermal, and oral. This review article describes the marked potential of submicron emulsions for oral drug delivery owing to their numerous advantages like reduced first pass metabolism, inhibition of P-glycoprotein efflux system, and enhanced absorption via intestinal lymphatic pathway. To overcome the limitations of liquid dosage forms, submicron emulsions can be formulated into solid dosage forms such as solid self-emulsifying systems. This article covers various types of submicron emulsions like microemulsion, nanoemulsion, and self-emulsifying drug delivery system (SEDDS), and their potential pharmaceutical applications in oral delivery with emphasis on their advantages, limitations, and advancements.

Design and application of water-in-oil emulsions for use in lipstick formulations.

PubMed

Le Révérend, B J D; Taylor, M S; Norton, I T

2011-06-01

The addition of water to lipsticks in the form of a water-in-oil emulsion is an attractive opportunity for cosmetics manufacturers to deliver hydrophilic molecules to the consumers, as well as improving the moisturizing properties. In this work, the effect of the emulsifier type and water content on the structural properties of the designed products was investigated. It has been shown that PGPR leads to smaller droplets than the other emulsifiers tested. This was attributed to the ability of PGPR to form elastic interfaces that slow the coalescence between droplets during the process. It was also observed that crystals of wax tend to form structures at the interface upon cooling that prevent coalescence during storage. These structures also prevent leakage of water into the continuous phase. No effect of the water content on the melting properties of the emulsions was observed. Upon addition of more than 10% water, softening of the material was measured, due to the overall decrease in solid content. Addition of crystalline material (hard paraffin) was successfully used to reinstate the material properties. © 2011 The Authors. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

HFE Gene Mutations and Iron Status in 100 Healthy Polish Children.

PubMed

Kaczorowska-Hac, Barbara; Luszczyk, Marcin; Antosiewicz, Jedrzej; Ziolkowski, Wieslaw; Adamkiewicz-Drozynska, Elzbieta; Mysliwiec, Malgorzata; Milosz, Ewa; Kaczor, Jan J

2017-07-01

Iron participates in oxygen transport, energetic, metabolic, and immunologic processes. There are 2 main causes of iron overload: hereditary hemochromatosis which is a primary cause, is a metabolic disorder caused by mutations of genes that control iron metabolism and secondary hemochromatosis caused by multitransfusions, chronic hemolysis, and intake of iron rich food. The most common type of hereditary hemochromatosis is caused by HFE gene mutation. In this study, we analyzed iron metabolism in 100 healthy Polish children in relation to their HFE gene status. The wild-type HFE gene was predominant being observed in 60 children (60%). Twenty-five children (25%), presented with heterozygotic H63D mutation, and 15 children (15%), presented with other mutations (heterozygotic C282Y and S65C mutation, compound heterozygotes C282Y/S65C, C282Y/H63D, H63D homozygote). The mean concentration of iron, the level of ferritin, and transferrin saturation were statistically higher in the group of HFE variants compared with the wild-type group. H63D carriers presented with higher mean concentration of iron, ferritin levels, and transferrin saturation compared with the wild-type group. Male HFE carriers presented with higher iron concentration, transferrin saturation, and ferritin levels than females. This preliminary investigation demonstrates allelic impact on potential disease progression from childhood.

Cardiac remodeling in response to chronic iron deficiency: role of the erythropoietin receptor.

PubMed

Naito, Yoshiro; Sawada, Hisashi; Oboshi, Makiko; Iwasaku, Toshihiro; Okuhara, Yoshitaka; Morisawa, Daisuke; Eguchi, Akiyo; Hirotani, Shinichi; Mano, Toshiaki; Tsujino, Takeshi; Masuyama, Tohru

2015-06-01

Anemia is a common comorbidity of patients with heart failure, and iron deficiency is known as one of the causes of anemia in heart failure. Recent studies have shown that iron deficiency alone, without overt anemia, is associated with poor outcomes in patients with heart failure. Thus, to minimize the mortality in patients with heart failure, it is important to understand the link between iron deficiency and cardiac function. Chronic untreated iron deficiency results in cardiac remodeling, and we have previously reported that erythropoietin (Epo) and cardiac Epo receptor (EpoR) signaling may be associated with its remodeling. However, the link between EpoR signaling and its remodeling remains to be elucidated. Herein, we investigated the role of EpoR signaling on cardiac remodeling in response to chronic iron deficiency. Wild-type mice and transgene-rescued EpoR-null mutant mice, which express EpoR only in the hematopoietic lineage (EpoR-restricted mice), were fed with either a normal or an iron-restricted diet, and the molecular mechanisms were investigated. Dietary iron restriction gradually induced anemia, Epo secretion, and cardiac hypertrophy in wild-type mice. In contrast, EpoR-restricted mice fed with an iron-restricted diet exhibited anemia, left ventricular dilatation, and cardiac dysfunction compared with wild-type mice. Interestingly, altered cardiac mitochondrial biogenesis was observed in EpoR-restricted mice following iron deficiency. Moreover, cardiac p53 expression was increased in EpoR-restricted mice compared with wild-type mice following iron deficiency. These data indicate that EpoR signaling is associated with cardiac remodeling following chronic iron deficiency.

Increase in type II collagen turnover after iron depletion in patients with hereditary haemochromatosis.

PubMed

Richette, Pascal; Eymard, Claire; Deberg, Michelle; Vidaud, Dominique; de Kerguenec, Caroline; Valla, Dominique; Vicaut, Eric; Bardin, Thomas; Henrotin, Yves

2010-04-01

To determine the effects of iron depletion on serum levels of joint biomarkers and on joint symptoms in patients with hereditary haemochromatosis (HH). Levels of biomarkers were measured in 18 patients with HH at the time of diagnosis and after iron depletion. The markers were type II collagen degradation (Coll2-1) and its nitrated form (Coll2-1NO(2)), type II procollagen synthesis (CPII), MPO, COMP and HA. For each patient, demographic data were collected and the global joint pain (visual analogue scale) was assessed before and after iron depletion by phlebotomy. A total of 18 patients [10 males; mean (s.d.) age 48 (11) years] were homozygous for the C282Y mutation. No patient had liver dysfunction. Ferritin level before iron removal was 627.5 (range 133-3276) microg/l, and duration of the iron depletion phase was 295 (70-670) days. Serum levels of both Coll2-1 and CPII were significantly increased from diagnosis after iron depletion: 80.1 (55.6-113.5) vs 96.0 (48.8-136.3) nM (P = 0.004) and 731.4 (374.2-1012.3) vs 812.8 (535.8-1165.6) ng/ml (P = 0.03), respectively. Levels of other biomarkers were not modified by iron depletion. Ferritin level, which at baseline was correlated with body iron store (r = 0.63; P = 0.008), was significantly correlated with HA level measured before iron depletion (r = 0.60; P = 0.01). Global joint pain was not correlated with ferritin concentration and did not significantly decrease after iron depletion: 43 (19-73) vs 36 (16-67) mm (P = 0.07). In patients with HH, cartilage homoeostasis is modified by iron excess and an increase in type II collagen turnover occurs after excess iron removal.

Lipid composition and emulsifying properties of canola lecithin from enzymatic degumming.

PubMed

Xie, Meizhen; Dunford, Nurhan Turgut

2017-03-01

This study investigated the polar lipid composition and emulsifying properties of canola lecithin from enzymatic degumming (CLED). Phospholipase A 1 was used for enzymatic degumming of crude canola oil to collect lecithin sample. Canola lecithin from water degumming (CLWD) was also collected and served as the control. The results showed that the contents of phosphatidylethanolamine (PE) (2.99%) and phosphatidylcholine (PC) (6.59%) in CLED were significantly lower than that in CLWD (PE 15.55% and PC 21.93%); while the content of lysophosphatidylcholine (LPC) (19.45%) in CLED was significantly higher than that in CLWD (3.27%). Unsaturated fatty acids accounted for a higher percentage of the total fatty acids in CLED than in CLWD. CLED promoted more stable o/w emulsions than CLWD. This study provides a better understanding of the chemical nature of CLED, and important information for utilization of CLED as o/w emulsifier. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural and emulsifying properties of soy protein isolate subjected to acid and alkaline pH-shifting processes.

PubMed

Jiang, Jiang; Chen, Jie; Xiong, Youling L

2009-08-26

Structural unfolding of soy protein isolate (SPI) as induced by holding (0, 0.5, 1, 2, and 4 h) in acidic (pH 1.5-3.5) and alkaline (pH 10.0-12.0) pH solutions, followed by refolding (1 h) at pH 7.0, was analyzed. Changes in emulsifying properties of treated SPI were then examined. The pH-shifting treatments resulted in a substantial increase in protein surface hydrophobicity, intrinsic tryptophan fluorescence intensity, and disulfide-mediated aggregation, along with the exposure of tyrosine. After the pH-shifting processes, soy protein adopted a molten globule-like conformation that largely maintained the original secondary structure and overall compactness but lost some tertiary structure. These structural modifications, consequently, led to markedly improved emulsifying activity of SPI as well as the emulsion stability.

Control of chironamics in milkfish (Chanos chanos) ponds with Abate (Temephos) insecticide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsai, S.C.

Larval chironomids (Chironomus longilobus (Kieffer) are serious competitors with milkfish Chanos chanos (Forskal) for benthic algae in commercial milkfish ponds in Taiwan. Chironomid larvae were effectively killed with temephos (Abate, 0, 0, 0', 0'-tetramethyl 0, 0'-thiodi-p-phenylene phosphorothioate) 50% emulsifiable concentrate when it was diluted 1:2,000 with seawater and applied to milkfish ponds to establish a concentration of 0.050 mg/liter of the active ingredient. This treatment did not harm milkfish and benthic algae. Residues found in the edible portions of milkfish after seven applications of Abate 50% emulsifiable concentrate ranged from 0.02 to 0.08 mg/kg, well below the 1.0 mg/liter approvedmore » by the World Health Organization for presence in human drinking water. The acute toxicity of Abate 50% emulsifiable concentrate to 13 other species of aquatic animals was determined in the laboratory.« less

A minimal length rigid helical peptide motif allows rational design of modular surfactants

NASA Astrophysics Data System (ADS)

Mondal, Sudipta; Varenik, Maxim; Bloch, Daniel Nir; Atsmon-Raz, Yoav; Jacoby, Guy; Adler-Abramovich, Lihi; Shimon, Linda J. W.; Beck, Roy; Miller, Yifat; Regev, Oren; Gazit, Ehud

2017-01-01

Extensive work has been invested in the design of bio-inspired peptide emulsifiers. Yet, none of the formulated surfactants were based on the utilization of the robust conformation and self-assembly tendencies presented by the hydrophobins, which exhibited highest surface activity among all known proteins. Here we show that a minimalist design scheme could be employed to fabricate rigid helical peptides to mimic the rigid conformation and the helical amphipathic organization. These designer building blocks, containing natural non-coded α-aminoisobutyric acid (Aib), form superhelical assemblies as confirmed by crystallography and microscopy. The peptide sequence is amenable to structural modularity and provides the highest stable emulsions reported so far for peptide and protein emulsifiers. Moreover, we establish the ability of short peptides to perform the dual functions of emulsifiers and thickeners, a feature that typically requires synergistic effects of surfactants and polysaccharides. This work provides a different paradigm for the molecular engineering of bioemulsifiers.

Contact-Allergic Reactions to Cosmetics

PubMed Central

Goossens, An

2011-01-01

Contact-allergic reactions to cosmetics may be delayed-type reactions such as allergic and photo-allergic contact dermatitis, and more exceptionally also immediate-type reactions, that is, contact urticaria. Fragrances and preservative agents are the most important contact allergens, but reactions also occur to category-specific products such as hair dyes and other hair-care products, nail cosmetics, sunscreens, as well as to antioxidants, vehicles, emulsifiers, and, in fact, any possible cosmetic ingredient. Patch and prick testing to detect the respective culprits remains the golden standard for diagnosis, although additional tests might be useful as well. Once the specific allergens are identified, the patients should be informed of which products can be safely used in the future. PMID:21461388

An Atlas of extraterrestrial particles collected with NASA U-2 aircraft, 1974 - 1976

NASA Technical Reports Server (NTRS)

Brownlee, D. E.; Tomandl, D.; Blanchard, M. B.; Ferry, G. V.; Kyte, F.

1976-01-01

Extraterrestrial particles collected during U-2 flights in the stratosphere were divided into four groups: chondritic, iron-sulfur--nickel, mafic silicates, and others. The chondritic aggregates are typically composed of Fe, Mg, Si, C, S, Ca, and Ni. Detectable levels of He-4 implanted from the solar wind occur in some. Olivine, spinel, and possibly pyrrhotite and a hydrated layered-lattice silicate were identified. The chondritic ablation particles contain no sulfur and appear to have been melted. Magnetite, olivine, and pyroxene were identified. The iron-sulfur-nickel type particles resemble meteoritic iron sulfide with a small amount of nickel, and contain magnetite and troilite. The mafic silicate type particles are iron magnesium silicate grains with clumps of chondritic aggregate particles adhering to their surfaces. Olivine and possibly pyrrhotite and pyroxene were identified. Most of the iron-nickel type particles are spherules and include taenite and wustite. The other type particles include nickel-iron mounds on spheroidal glassy-like grains having chondritic-like elemental abundances.

Candida albicans Hap43 Is a Repressor Induced under Low-Iron Conditions and Is Essential for Iron-Responsive Transcriptional Regulation and Virulence ▿

PubMed Central

Hsu, Po-Chen; Yang, Cheng-Yao; Lan, Chung-Yu

2011-01-01

Candida albicans is an opportunistic fungal pathogen that exists as normal flora in healthy human bodies but causes life-threatening infections in immunocompromised patients. In addition to innate and adaptive immunities, hosts also resist microbial infections by developing a mechanism of “natural resistance” that maintains a low level of free iron to restrict the growth of invading pathogens. C. albicans must overcome this iron-deprived environment to cause infections. There are three types of iron-responsive transcriptional regulators in fungi; Aft1/Aft2 activators in yeast, GATA-type repressors in many fungi, and HapX/Php4 in Schizosaccharomyces pombe and Aspergillus species. In this study, we characterized the iron-responsive regulator Hap43, which is the C. albicans homolog of HapX/Php4 and is repressed by the GATA-type repressor Sfu1 under iron-sufficient conditions. We provide evidence that Hap43 is essential for the growth of C. albicans under low-iron conditions and for C. albicans virulence in a mouse model of infection. Hap43 was not required for iron acquisition under low-iron conditions. Instead, it was responsible for repression of genes that encode iron-dependent proteins involved in mitochondrial respiration and iron-sulfur cluster assembly. We also demonstrated that Hap43 executes its function by becoming a transcriptional repressor and accumulating in the nucleus in response to iron deprivation. Finally, we found a connection between Hap43 and the global corepressor Tup1 in low-iron-induced flavinogenesis. Taken together, our data suggest a complex interplay among Hap43, Sfu1, and Tup1 to coordinately regulate iron acquisition, iron utilization, and other iron-responsive metabolic activities. PMID:21131439

Development of Army High-Energy Fuel for Diesel/Turbine Powered Surface Equipment

DTIC Science & Technology

1979-10-01

approximately CH2(R)CH(RI)CH2 OPO(OH)O(CH2 ) 2 N(OH)(CH 3 ) 3 , where R and R1 are fatty acid groups. The phosphatides are mixtures of diglyceride residues from...In the JP-lO/H2 0 microemulsions, three different emulsifying agents were used, all similar in type, but with varying acid numbers. The agents...designated as EA-8, EA-12, and EA-37, had acid numbers of approximately 14, 18.5, and >20, respectively. All three were visually stable (no settling) for 1

Overexpression of Arabidopsis VIT1 increases accumulation of iron in cassava roots and stems.

PubMed

Narayanan, Narayanan; Beyene, Getu; Chauhan, Raj Deepika; Gaitán-Solis, Eliana; Grusak, Michael A; Taylor, Nigel; Anderson, Paul

2015-11-01

Iron is extremely abundant in the soil, but its uptake in plants is limited due to low solubility in neutral or alkaline soils. Plants can rely on rhizosphere acidification to increase iron solubility. AtVIT1 was previously found to be involved in mediating vacuolar sequestration of iron, which indicates a potential application for iron biofortification in crop plants. Here, we have overexpressed AtVIT1 in the starchy root crop cassava using a patatin promoter. Under greenhouse conditions, iron levels in mature cassava storage roots showed 3-4 times higher values when compared with wild-type plants. Significantly, the expression of AtVIT1 showed a positive correlation with the increase in iron concentration of storage roots. Conversely, young leaves of AtVIT1 transgenic plants exhibit characteristics of iron deficiency such as interveinal chlorosis of leaves (yellowing) and lower iron concentration when compared with the wild type plants. Interestingly, the AtVIT1 transgenic plants showed 4 and 16 times higher values of iron concentration in the young stem and stem base tissues, respectively. AtVIT1 transgenic plants also showed 2-4 times higher values of iron content when compared with wild-type plants, with altered partitioning of iron between source and sink tissues. These results demonstrate vacuolar iron sequestration as a viable transgenic strategy to biofortify crops and to help eliminate micronutrient malnutrition in at-risk human populations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Dial-A-Decon Solution Chemistry GAP Testing

DTIC Science & Technology

2012-04-01

34 The tubes were serially diluted using Buttcrfield’s buffer solution and plated in triplicate on Tryptic Soy Agar. Plates were enumerated the...of 200 uL HD to 10 mL of the surfactant solution. The energy to create the oil in water (O/W) emulsions was provided by magnetic stirring. Solutions...emulsify a mixture of water and oil such as HD, one or more emulsifiers are required. Each surfactant system can be characterized by an HLB value

Nanoparticle-Based Topical Ophthalmic Gel Formulation for Sustained Release of Hydrocortisone Butyrate.

PubMed

Yang, Xiaoyan; Trinh, Hoang M; Agrahari, Vibhuti; Sheng, Ye; Pal, Dhananjay; Mitra, Ashim K

2016-04-01

This study was conducted to develop formulations of hydrocortisone butyrate (HB)-loaded poly(D,L-lactic-co-glycolic acid) nanoparticles (PLGA NP) suspended in thermosensitive gel to improve ocular bioavailability of HB for the treatment of bacterial corneal keratitis. PLGA NP with different surfactants such as polyvinyl alcohol (PVA), pluronic F-108, and chitosan were prepared using oil-in-water (O/W) emulsion evaporation technique. NP were characterized with respect to particle size, entrapment efficiency, polydispersity, drug loading, surface morphology, zeta potential, and crystallinity. In vitro release of HB from NP showed a biphasic release pattern with an initial burst phase followed by a sustained phase. Such burst effect was completely eliminated when nanoparticles were suspended in thermosensitive gels and zero-order release kinetics was observed. In HCEC cell line, chitosan-emulsified NP showed the highest cellular uptake efficiency over PVA- and pluronic-emulsified NP (59.09 ± 6.21%, 55.74 ± 6.26%, and 62.54 ± 3.30%, respectively) after 4 h. However, chitosan-emulsified NP indicated significant cytotoxicity of 200 and 500 μg/mL after 48 h, while PVA- and pluronic-emulsified NP exhibited no significant cytotoxicity. PLGA NP dispersed in thermosensitive gels can be considered as a promising drug delivery system for the treatment of anterior eye diseases.

The effect of clove bud powder at a spice level on antioxidant and quality properties of emulsified pork sausage during cold storage.

PubMed

Jin, Sang-Keun; Choi, Jung-Seok; Jeong, Jin-Yeon; Kim, Gap-Don

2016-09-01

Clove bud is a widely used spice in meat and meat products, and it contains high level of phenolic compounds. The effectiveness of the clove as a spice has not been fully studied at a general level of addition in the meat products. Therefore, in the present study, the antioxidant, antimicrobial, and nitrite scavenging abilities of clove bud powder (CBP) was assessed at spice level (0.1% and 0.2%) in emulsified pork sausage, during 6 weeks of cold storage. CBP had DPPH radical scavenging ability, but CBP addition at 0.1% and 0.2% did not decrease the TBARS value. An antimicrobial effect of CBP was also not observed during the cold storage. However, residual nitrite at storage weeks 4 and 6 was shown to be lower (P < 0.05). Addition of CBP decreased CIE L* and a* values, but it produced unacceptable sensory properties. Texture profile analysis was not affected by the addition of CBP in emulsified pork sausage (P > 0.05). The positive effect on nitrite scavenging could be expected by the addition of 0.2% CBP as a spice. However, antioxidant and antimicrobial abilities were not observed, as well as improvement in the quality of characteristics, in emulsified pork sausage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Emulsifying properties of legume proteins compared to β-lactoglobulin and Tween 20 and the volatile release from oil-in-water emulsions.

PubMed

Benjamin, O; Silcock, P; Beauchamp, J; Buettner, A; Everett, D W

2014-10-01

The emulsifying properties of plant legume protein isolates (soy, pea, and lupin) were compared to a milk whey protein, β-lactoglobulin (β-lg), and a nonionic surfactant (Tween 20). The protein fractional composition was characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The following emulsion properties were measured: particle diameter, shear surface ζ-potential, interfacial tension (IT), and creaming velocity. The effect of protein preheat treatment (90 °C for 10 min) on the emulsifying behavior and the release of selected volatile organic compounds (VOCs) from emulsions under oral conditions was also investigated in real time using proton transfer reaction-mass spectrometry. The legume proteins showed comparable results to β-lg and Tween 20, forming stable, negatively charged emulsions with particle diameter d3,2 < 0.4 μm, and maintained stability over 50 d. The relatively lower stability of lupin emulsions was significantly correlated with the low protein surface hydrophobicity and IT of the emulsion. After heating the proteins, the droplet size of pea and lupin emulsions decreased. The VOC release profile was similar between the protein-stabilized emulsions, and greater retention was observed for Tween 20-stabilized emulsions. This study demonstrates the potential application of legume proteins as alternative emulsifiers to milk proteins in emulsion products. © 2014 Institute of Food Technologists®

Synergistic Combinations of a Pyrethroid Insecticide and an Emulsifiable Oil Formulation of Beauveria bassiana to Overcome Insecticide Resistance in Listronotus maculicollis (Coleoptera: Curculionidae).

PubMed

Wu, Shaohui; Kostromytska, Olga S; Koppenhöfer, Albrecht M

2017-08-01

The annual bluegrass weevil, Listronotus maculicollis (Kirby), is a major pest of golf course turf in eastern North America and has become particularly problematic owing to widespread development of insecticide resistance. As an alternative option to manage resistant adult L. maculicollis, we explored combinations of the pyrethroid insecticide bifenthrin with an emulsifiable oil formulation of the entomopathogenic fungus Beauveria bassiana strain GHA (Bb ES). Combinations synergistically enhanced mortality in both insecticide-susceptible and insecticide-resistant L. maculicollis adults in the laboratory when bifenthrin was used at LC50s for each population. To determine the component behind the synergism, technical spores of B. bassiana GHA and the emulsifiable oil carrier in the fungal formulation were tested separately or in combination with bifenthrin. In both separate and combined applications, the emulsifiable oil carrier was responsible for high mortality within 3 d after treatment and interacted synergistically with bifenthrin, whereas fungus-induced mortality started later. Strong synergism was also observed in three field experiments with a relatively resistant L. maculicollis population. Combinations of Bb ES and bifenthrin hold promise as an effective L. maculicollis management tool, particularly of pyrethroid-resistant populations. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fabrication and Properties of Micro-Nanoencapsulated Phase Change Materials for Internally-Cooled Liquid Desiccant Dehumidification.

PubMed

Niu, Xiaofeng; Xu, Qing; Zhang, Yi; Zhang, Yue; Yan, Yufeng; Liu, Tao

2017-04-29

Micro-nanoencapsulated phase change materials (M-NEPCMs) are proposed to be useful in liquid desiccant dehumidification by restraining the temperature rise in the moisture-removal process and improving the dehumidification efficiency. In this paper, the n -octadecane M-NEPCMs with desirable thermal properties for internally-cooled dehumidification were fabricated by using compound emulsifiers through the in-situ polymerization method. Melamine-formaldehyde resin was used as the shell material. The effects of the mixing ratio, emulsification methods and amount of the compound emulsifiers on the morphology, size and thermal properties of the M-NEPCMs were investigated experimentally. The optimum weight mixing ratio of the compound emulsifiers is SDS (sodium dodecyl sulfate):Tween80 (polyoxyethylene sorbitan monooleate):Span80 (sorbitan monooleate) = 0.1:0.6:0.3, which achieves the best stability of the n -octadecane emulsion. When the compound emulsifiers are 10 wt. % of the core material, the melting enthalpy of M-NEPCMs reaches its maximum of 145.26 J/g of capsules, with an encapsulation efficiency of 62.88% and a mean diameter of 636 nm. The sub-cooling of the prepared M-NEPCMs is lower than 3 °C, with an acceptable thermal reliability after the thermal cycling test. A pre-emulsification prior to the addition of deionized water in the emulsification is beneficial to the morphology of the capsules, as the phase change enthalpy can be increased by 123.7%.

A long-term high-fat diet changes iron distribution in the body, increasing iron accumulation specifically in the mouse spleen.

PubMed

Yamano, Noriko; Ikeda, Yasumasa; Sakama, Minoru; Izawa-Ishizawa, Yuki; Kihira, Yoshitaka; Ishizawa, Keisuke; Miyamoto, Licht; Tomita, Shuhei; Tsuchiya, Koichiro; Tamaki, Toshiaki

2015-01-01

Although iron is an essential trace metal, its presence in excess causes oxidative stress in the human body. Recent studies have indicated that iron storage is a risk factor for type 2 diabetes mellitus. Dietary iron restriction or iron chelation ameliorates symptoms of type 2 diabetes in mouse models. However, whether iron content in the body changes with the development of diabetes is unknown. Here, we investigated the dynamics of iron accumulation and changes in iron absorption-related genes in mice that developed obesity and diabetes by consuming a high-fat diet (HFD-fed mice). HFD-fed mice (18-20 wk) were compared with control mice for hematologic features, serum ferritin levels, and iron contents in the gastrocnemius muscle, heart, epididymal fat, testis, liver, duodenum, and spleen. In addition, the spleen was examined histologically. Iron absorption-related gene expression in the liver and duodenum was also examined. Hemoglobin and serum ferritin levels were increased in HFD-fed mice. The HFD-fed mice showed iron accumulation in the spleen, but not in the heart or liver. Increased percentages of the splenic red pulp and macrophages were observed in HFD-fed mice and iron accumulation in the spleen was found mainly in the splenic red pulp. The HFD-fed mice also showed decreased iron content in the duodenum. The mRNA expression of divalent metal transporter-1 (DMT-1), an iron absorption-related gene, was elevated in the duodenum of HFD-fed mice. These results indicate that iron accumulation (specifically accumulation in the spleen) is enhanced by the development of type 2 diabetes induced by HFD.

Iron-Dependent Regulation of Hepcidin in Hjv−/− Mice: Evidence That Hemojuvelin Is Dispensable for Sensing Body Iron Levels

PubMed Central

Daba, Alina; Wagner, John; Sebastiani, Giada; Pantopoulos, Kostas

2014-01-01

Hemojuvelin (Hjv) is a bone morphogenetic protein (BMP) co-receptor involved in the control of systemic iron homeostasis. Functional inactivation of Hjv leads to severe iron overload in humans and mice due to marked suppression of the iron-regulatory hormone hepcidin. To investigate the role of Hjv in body iron sensing, Hjv−/− mice and isogenic wild type controls were placed on a moderately low, a standard or a high iron diet for four weeks. Hjv−/− mice developed systemic iron overload under all regimens. Transferrin (Tf) was highly saturated regardless of the dietary iron content, while liver iron deposition was proportional to it. Hepcidin mRNA expression responded to fluctuations in dietary iron intake, despite the absence of Hjv. Nevertheless, iron-dependent upregulation of hepcidin was more than an order of magnitude lower compared to that seen in wild type controls. Likewise, iron signaling via the BMP/Smad pathway was preserved but substantially attenuated. These findings suggest that Hjv is not required for sensing of body iron levels and merely functions as an enhancer for iron signaling to hepcidin. PMID:24409331

Siderophore-mediated iron acquisition mechanisms in Vibrio vulnificus biotype 2.

PubMed Central

Biosca, E G; Fouz, B; Alcaide, E; Amaro, C

1996-01-01

Vibrio vulnificus biotype 2 is a primary pathogen for eels and, as has recently been suggested, an opportunistic pathogen for humans. In this study we have investigated the ability of V. vulnificus biotype 2 to obtain iron by siderophore-mediated mechanisms and evaluated the importance of free iron in vibriosis. The virulence degree for eels was dependent on iron availability from host fluids, as was revealed by a reduction in the 50% lethal dose for iron-overloaded eels. This biotype produced both phenolate- and hydroxamate-type siderophores of an unknown nature and two new outer membrane proteins of around 84 and 72 kDa in response to iron starvation. No alterations in lipopolysaccharide patterns were detected in response to iron stress. Finally, our data suggest that V. vulnificus biotype 2 uses the hydroxamate-type siderophore for removal of iron from transferrin rather than relying on a receptor for this iron-binding protein. PMID:8975620

Preparation and characterization of polymer-coated core-shell structured magnetic microbeads

NASA Astrophysics Data System (ADS)

Liu, Z. L.; Ding, Z. H.; Yao, K. L.; Tao, J.; Du, G. H.; Lu, Q. H.; Wang, X.; Gong, F. L.; Chen, X.

2003-09-01

Composite microbeads consisting of polymer-coated iron oxide nanoparticles are prepared by the microemulsion polymerization of styrene, divinyl benzene and methacrylic acid in the presence of emulsifiers. Fourier transform infrared spectrometer analysis indicates the presence of -COOH groups and Fe 3O 4 of the microbeads. The amount of -COOH groups localized on the surface, which is about 0.15 mmol/g, is determined by conductometric titration. Transmission electron microscope picture reveals that the microbeads have a core-shell structure. The dissolving experiments of microbeads in hydrochloric acid and toluene further identify the core-shell structure. Optical microscope indicates that the magnetic microbeads have uniform and spherical forms with the size of 1-5 μm. Magnetic sensitivity measurement indicates that the microbeads can be used conveniently. Magnetic property measurement shows very little residual magnetization and coercivity, which are below 0.5 emu/g and around 15 Oe, respectively. The magnetic properties are greatly related to the particle sizes. The thermal gravity analysis result shows the improvement of thermal stability. The experiment of immobilized antibody indicates that the functional groups on the surface are appropriate.

BMP type II receptors have redundant roles in the regulation of hepatic hepcidin gene expression and iron metabolism.

PubMed

Mayeur, Claire; Leyton, Patricio A; Kolodziej, Starsha A; Yu, Binglan; Bloch, Kenneth D

2014-09-25

Expression of hepcidin, the hepatic hormone controlling iron homeostasis, is regulated by bone morphogenetic protein (BMP) signaling. We sought to identify which BMP type II receptor expressed in hepatocytes, ActR2a or BMPR2, is responsible for regulating hepcidin gene expression. We studied Bmpr2 heterozygous mice (Bmpr2(+/-)), mice with hepatocyte-specific deficiency of BMPR2, mice with global deficiency of ActR2a, and mice in which hepatocytes lacked both BMPR2 and ActR2a. Hepatic hepcidin messenger RNA (mRNA) levels, serum hepcidin and iron levels, and tissue iron levels did not differ in wild-type mice, Bmpr2(+/-) mice, and mice in which either BMPR2 or ActR2a was deficient. Deficiency of both BMP type II receptors markedly reduced hepatic hepcidin gene expression and serum hepcidin levels leading to severe iron overload. Iron injection increased hepatic hepcidin mRNA levels in mice deficient in either BMPR2 or ActR2a, but not in mice deficient in both BMP type II receptors. In addition, in mouse and human primary hepatocytes, deficiency of both BMPR2 and ActR2a profoundly decreased basal and BMP6-induced hepcidin gene expression. These results suggest that BMP type II receptors, BMPR2 and ActR2a, have redundant roles in the regulation of hepatic hepcidin gene expression and iron metabolism. © 2014 by The American Society of Hematology.

Enhanced reductive dechlorination in columns treated with edible oil emulsion

NASA Astrophysics Data System (ADS)

Long, Cameron M.; Borden, Robert C.

2006-09-01

The effect of edible oil emulsion treatment on enhanced reductive dechlorination was evaluated in a 14 month laboratory column study. Experimental treatments included: (1) emulsified soybean oil and dilute HCl to inhibit biological activity; (2) emulsified oil only; (3) emulsified oil and anaerobic digester sludge; and (4) continuously feeding soluble substrate. A single application of emulsified oil was effective in generating strongly reducing, anaerobic conditions for over 14 months. PCE was rapidly reduced to cis-DCE in all three live columns. Bioaugmentation with a halorespiring enrichment culture resulted in complete dechlorination of PCE to ethene in the soluble substrate column (yeast extract and lactate). However, an additional treatment with a pulse of yeast extract and bioaugmentation culture was required to stimulate complete dechlorination in the emulsion treated columns. Once the dechlorinating population was established, the emulsion only column degraded PCE from 90-120 μM to below detection with concurrent ethene production in a 33 day contact time. The lower biodegradation rates in the emulsion treated columns compared to the soluble substrate column suggest that emulsified oil barriers may require a somewhat longer contact time for effective treatment. In the HCl inhibited column, partitioning of PCE to the retained oil substantially delayed PCE breakthrough. However, reduction of PCE to more soluble degradation products ( cis-DCE, VC and ethene) greatly reduced the impact of oil-water partitioning in live columns. There was only a small decline in the hydraulic conductivity ( K) of column #1 (low pH + emulsion, Kfinal/ Kinitial = 0.57) and column #2 (live + emulsion, Kfinal/ Kinitial = 0.73) indicating emulsion injection did not result in appreciable clogging of the clayey sand. However, K loss was greater in column #3 (sludge +emulsion, Kfinal/ Kinitial = 0.12) and column #4 (soluble substrate, Kfinal/ Kinitial = 0.03) indicating clogging due to biomass and/or gas production can be significant.

SPE-UPLC-MS/MS for the determination of phthalate monoesters in rats urine and its application to study the effects of food emulsifier on the bioavailability of priority controlling PAEs.

PubMed

Xu, R; Gao, H T; Zhu, F; Cao, W X; Yan, Y H M; Zhou, X; Xu, Q; Ji, W L

2016-02-15

This research was mainly focused on the effects of food emulsifier on the bioavailability of six priority controlling phthalate acid esters (PAEs) for the further accurate assessment of their toxic effects, using the corresponding phthalate acid monoesters (PAMEs) in rats urine as biomarkers. Glycerin monostearate was chosen as typical food emulsifier. A method was established to determine PAMEs in urine from rats either in experimental group (integrated gavaged with glycerin monostearate and PAEs) or in control group (gavaged with PAEs only), by using solid-phase extraction (SPE) coupled with ultra performance liquid chromatography tandem mass spectrometry (SPE-UPLC-MS/MS). Extraction recoveries were more than 75% for all the PAMEs; the calibration curve was linear in the range of 1.0-1000.0ng/mL with R(2)>0.995; the limits of detection (LOD) were 0.30ng/mL-0.50ng/mL. In addition, by analysing quality control (QC) urine samples in 3 days, it showed that the method was precise and accurate, for the intra-day and inter-day RSD within 16%, and the accuracy more than 82%. Internal exposure amount of all PAEs in experimental group was significantly higher than that in control group with p values of less than 0.05 except for butyl benzyl phthalates (BBP) (P=0.07). The bioavailability of all PAEs ranged from 5.03% to 109.35% with the presence of food emulsifiers glycerin monostearate, observably higher than that without glycerin monostearate (1.12% to 54.39%). It indicated that food emulsifiers increased the bioavailability of PAEs and may lead to potential food safety risk, which should bring awareness and be further studied. Copyright © 2016 Elsevier B.V. All rights reserved.

Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome

PubMed Central

Chassaing, Benoit; Koren, Omry; Goodrich, Julia; Poole, Angela; Srinivasan, Shanthi; Ley, Ruth E.; Gewirtz, Andrew T.

2015-01-01

Summary The intestinal tract is inhabited by a large diverse community of microbes collectively referred to as gut microbiota. While gut microbiota provide important benefits to its host, especially in metabolism and immune development, disturbance of the microbiota-host relationship is associated with numerous chronic inflammatory diseases, including inflammatory bowel disease (IBD) and the group of obesity-associated diseases collectively referred to as metabolic syndrome. A primary means by which the intestine is protected from its microbiota is via multilayered mucus structures that cover the intestinal surface thus allowing the vast majority of gut bacteria to be kept at a safe distance from epithelial cells that line the intestine 1. Thus, agents that disrupt mucus-bacterial interactions might have the potential to promote diseases associated with gut inflammation. Consequently, it has been hypothesized that emulsifiers, detergent-like molecules that are a ubiquitous component of processed foods and that can increase bacterial translocation across epithelia in vitro 2, might be promoting the post-mid 20th century increase in IBD 3. Herein, we observed that, in mice, relatively low concentrations of two commonly used emulsifiers, namely carboxymethylcellulose and polysorbate-80, induced low-grade inflammation and obesity/metabolic syndrome in WT hosts and promoted robust colitis in mice predisposed to this disorder. Emulsifier-induced metabolic syndrome was associated with microbiota encroachment, altered species composition, and increased pro-inflammatory potential. Use of germ-free mice and fecal transplants indicated that such changes in microbiota were necessary and sufficient for both low-grade inflammation and metabolic syndrome. These results support the emerging concept that perturbed host-microbiota interactions resulting in low-grade inflammation can promote adiposity and its associated metabolic effects. Moreover, they suggest that broad use of emulsifying agents might be contributing to increased societal incidence of obesity/metabolic syndrome and other chronic inflammatory diseases. PMID:25731162

Modeling complex and multi-component food systems in molecular dynamics simulations on the example of chocolate conching.

PubMed

Greiner, Maximilian; Sonnleitner, Bettina; Mailänder, Markus; Briesen, Heiko

2014-02-01

Additional benefits of foods are an increasing factor in the consumer's purchase. To produce foods with the properties the consumer demands, understanding the micro- and nanostructure is becoming more important in food research today. We present molecular dynamics (MD) simulations as a tool to study complex and multi-component food systems on the example of chocolate conching. The process of conching is chosen because of the interesting challenges it provides: the components (fats, emulsifiers and carbohydrates) contain diverse functional groups, are naturally fluctuating in their chemical composition, and have a high number of internal degrees of freedom. Further, slow diffusion in the non-aqueous medium is expected. All of these challenges are typical to food systems in general. Simulation results show the suitability of present force fields to correctly model the liquid and crystal density of cocoa butter and sucrose, respectively. Amphiphilic properties of emulsifiers are observed by micelle formation in water. For non-aqueous media, pulling simulations reveal high energy barriers for motion in the viscous cocoa butter. The work for detachment of an emulsifier from the sucrose crystal is calculated and matched with detachment of the head and tail groups separately. Hydrogen bonding is shown to be the dominant interaction between the emulsifier and the crystal surface. Thus, MD simulations are suited to model the interaction between the emulsifier and sugar crystal interface in non-aqueous media, revealing detailed information about the structuring and interactions on a molecular level. With interaction parameters being available for a wide variety of chemical groups, MD simulations are a valuable tool to understand complex and multi-component food systems in general. MD simulations provide a substantial benefit to researchers to verify their hypothesis in dynamic simulations with an atomistic resolution. Rapid rise of computational resources successively increases the complexity and the size of the systems that can be studied.

Iron metabolism and related genetic diseases: A cleared land, keeping mysteries.

PubMed

Brissot, Pierre; Loréal, Olivier

2016-02-01

Body iron has a very close relationship with the liver. Physiologically, the liver synthesizes transferrin, in charge of blood iron transport; ceruloplasmin, acting through its ferroxidase activity; and hepcidin, the master regulator of systemic iron. It also stores iron inside ferritin and serves as an iron reservoir, both protecting the cell from free iron toxicity and ensuring iron delivery to the body whenever needed. The liver is first in line for receiving iron from the gut and the spleen, and is, therefore, highly exposed to iron overload when plasma iron is in excess, especially through its high affinity for plasma non-transferrin bound iron. The liver is strongly involved when iron excess is related either to hepcidin deficiency, as in HFE, hemojuvelin, hepcidin, and transferrin receptor 2 related haemochromatosis, or to hepcidin resistance, as in type B ferroportin disease. It is less involved in the usual (type A) form of ferroportin disease which targets primarily the macrophagic system. Hereditary aceruloplasminemia raises important pathophysiological issues in light of its peculiar organ iron distribution. Copyright © 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Comparison of high-resolution ultrasonic resonator technology and Raman spectroscopy as novel process analytical tools for drug quantification in self-emulsifying drug delivery systems.

PubMed

Stillhart, Cordula; Kuentz, Martin

2012-02-05

Self-emulsifying drug delivery systems (SEDDS) are complex mixtures in which drug quantification can become a challenging task. Thus, a general need exists for novel analytical methods and a particular interest lies in techniques with the potential for process monitoring. This article compares Raman spectroscopy with high-resolution ultrasonic resonator technology (URT) for drug quantification in SEDDS. The model drugs fenofibrate, indomethacin, and probucol were quantitatively assayed in different self-emulsifying formulations. We measured ultrasound velocity and attenuation in the bulk formulation containing drug at different concentrations. The formulations were also studied by Raman spectroscopy. We used both, an in-line immersion probe for the bulk formulation and a multi-fiber sensor for measuring through hard-gelatin capsules that were filled with SEDDS. Each method was assessed by calculating the relative standard error of prediction (RSEP) as well as the limit of quantification (LOQ) and the mean recovery. Raman spectroscopy led to excellent calibration models for the bulk formulation as well as the capsules. The RSEP depended on the SEDDS type with values of 1.5-3.8%, while LOQ was between 0.04 and 0.35% (w/w) for drug quantification in the bulk. Similarly, the analysis of the capsules led to RSEP of 1.9-6.5% and LOQ of 0.01-0.41% (w/w). On the other hand, ultrasound attenuation resulted in RSEP of 2.3-4.4% and LOQ of 0.1-0.6% (w/w). Moreover, ultrasound velocity provided an interesting analytical response in cases where the drug strongly affected the density or compressibility of the SEDDS. We conclude that ultrasonic resonator technology and Raman spectroscopy constitute suitable methods for drug quantification in SEDDS, which is promising for their use as process analytical technologies. Copyright © 2011 Elsevier B.V. All rights reserved.

Effect of crumb cellular structure characterized by image analysis on cake softness.

PubMed

Dewaest, Marine; Villemejane, Cindy; Berland, Sophie; Neron, Stéphane; Clement, Jérôme; Verel, Aliette; Michon, Camille

2018-06-01

Sponge cake is a cereal product characterized by an aerated crumb and appreciated for its softness. When formulating such product, it is interesting to be able to characterize the crumb structure using image analysis and to bring knowledge about the effects of the crumb cellular structure on its mechanical properties which contribute to softness. An image analysis method based on mathematical morphology was adapted from the one developed for bread crumb. In order to evaluate its ability to discriminate cellular structures, series of cakes were prepared using two rather similar emulsifiers but also using flours with different aging times before use. The mechanical properties of the crumbs of these different cakes were also characterized. It allowed a cell structure classification taking into account cell size and homogeneity, but also cell wall thickness and the number of holes in the walls. Interestingly, the cellular structure differences had a larger impact on the aerated crumb Young modulus than the wall firmness. Increasing the aging time of flour before use leads to the production of firmer crumbs due to coarser and inhomogeneous cellular structures. Changing the composition of the emulsifier may change the cellular structure and, depending on the type of the structural changes, have an impact on the firmness of the crumb. Cellular structure rather than cell wall firmness was found to impact cake crumb firmness. The new fast and automated tool for cake crumb structure analysis allows detecting quickly any change in cell size or homogeneity but also cell wall thickness and number of holes in the walls (openness degree). To obtain a softer crumb, it seems that options are to decrease the cell size and the cell wall thickness and/or to increase the openness degree. It is then possible to easily evaluate the effects of ingredients (flour composition, emulsifier …) or change in the process on the crumb structure and thus its softness. Moreover, this image analysis is a very efficient tool for quality control. © 2017 Wiley Periodicals, Inc.

Plant Extract Synthesized PLA Nanoparticles for Controlled and Sustained Release of Quercetin: A Green Approach

PubMed Central

Yadav, Sudesh Kumar

2012-01-01

Background Green synthesis of metallic nanoparticles (NPs) has been extensively carried out by using plant extracts (PEs) which have property of stabilizers/ emulsifiers. To our knowledge, there is no comprehensive study on applying a green approach using PEs for fabrication of biodegradable PLA NPs. Conventional methods rely on molecules like polyvinyl alcohol, polyethylene glycol, D-alpha-tocopheryl poly(ethylene glycol 1000) succinate as stabilizers/emulsifiers for the synthesis of such biodegradable NPs which are known to be toxic. So, there is urgent need to look for stabilizers which are biogenic and non-toxic. The present study investigated use of PEs as stabilizers/emulsifiers for the fabrication of stable PLA NPs. Synthesized PLA NPs through this green process were explored for controlled release of the well known antioxidant molecule quercetin. Methodology/Principal Findings Stable PLA NPs were synthesized using leaf extracts of medicinally important plants like Syzygium cumini (1), Bauhinia variegata (2), Cedrus deodara (3), Lonicera japonica (4) and Eleaocarpus sphaericus (5). Small and uniformly distributed NPs in the size range 70±30 nm to 143±36 nm were formed with these PEs. To explore such NPs for drugs/ small molecules delivery, we have successfully encapsulated quercetin a lipophilic molecule on a most uniformly distributed PLA-4 NPs synthesized using Lonicera japonica leaf extract. Quercetin loaded PLA-4 NPs were observed for slow and sustained release of quercetin molecule. Conclusions This green approach based on PEs mediated synthesis of stable PLA NPs pave the way for encapsulating drug/small molecules, nutraceuticals and other bioactive ingredients for safer cellular uptake, biodistribution and targeted delivery. Hence, such PEs synthesized PLA NPs would be useful to enhance the therapeutic efficacy of encapsulated small molecules/drugs. Furthermore, different types of plants can be explored for the synthesis of PLA as well as other polymeric NPs of smaller size. PMID:22844443

Dynamic Subcellular Localization of Iron during Embryo Development in Brassicaceae Seeds

PubMed Central

Ibeas, Miguel A.; Grant-Grant, Susana; Navarro, Nathalia; Perez, M. F.; Roschzttardtz, Hannetz

2017-01-01

Iron is an essential micronutrient for plants. Little is know about how iron is loaded in embryo during seed development. In this article we used Perls/DAB staining in order to reveal iron localization at the cellular and subcellular levels in different Brassicaceae seed species. In dry seeds of Brassica napus, Nasturtium officinale, Lepidium sativum, Camelina sativa, and Brassica oleracea iron localizes in vacuoles of cells surrounding provasculature in cotyledons and hypocotyl. Using B. napus and N. officinale as model plants we determined where iron localizes during seed development. Our results indicate that iron is not detectable by Perls/DAB staining in heart stage embryo cells. Interestingly, at torpedo development stage iron localizes in nuclei of different cells type, including integument, free cell endosperm and almost all embryo cells. Later, iron is detected in cytoplasmic structures in different embryo cell types. Our results indicate that iron accumulates in nuclei in specific stages of embryo maturation before to be localized in vacuoles of cells surrounding provasculature in mature seeds. PMID:29312417

The oil displacement effect evaluation of Different Displacing systems

NASA Astrophysics Data System (ADS)

Wang, Keliang; Zhang, Bowen; Li, Gen

2018-02-01

During the chemical flooding, the surfactant and the alkali play an emulsifying role. The emulsification can not only improve the displacement efficiency, but also expand the swept volume by the mechanism of emulsifying trapping. We select some chemical flooding systems including different kinds of surfactants, alkali/alkali-free and different emulsion degrees to make the comparative experiment and draw the conclusion that it is an effective way to enhance the recovery by increasing the emulsion stability without having to pursue the ultra-low interfacial tension.

Performance evaluation soil samples utilizing encapsulation technology

DOEpatents

Dahlgran, J.R.

1999-08-17

Performance evaluation soil samples and method of their preparation uses encapsulation technology to encapsulate analytes which are introduced into a soil matrix for analysis and evaluation by analytical laboratories. Target analytes are mixed in an appropriate solvent at predetermined concentrations. The mixture is emulsified in a solution of polymeric film forming material. The emulsified solution is polymerized to form microcapsules. The microcapsules are recovered, quantitated and introduced into a soil matrix in a predetermined ratio to form soil samples with the desired analyte concentration. 1 fig.

Performance evaluation soil samples utilizing encapsulation technology

DOEpatents

Dahlgran, James R.

1999-01-01

Performance evaluation soil samples and method of their preparation using encapsulation technology to encapsulate analytes which are introduced into a soil matrix for analysis and evaluation by analytical laboratories. Target analytes are mixed in an appropriate solvent at predetermined concentrations. The mixture is emulsified in a solution of polymeric film forming material. The emulsified solution is polymerized to form microcapsules. The microcapsules are recovered, quantitated and introduced into a soil matrix in a predetermined ratio to form soil samples with the desired analyte concentration.

Characterization of Acinetobacter baumannii strain PS3 in degradation of food emulsifiers

NASA Astrophysics Data System (ADS)

Nguyen, Ngoc Tuan; Tran, Tuyet Nhung; Ha, Thi Bich Ngoc

2018-04-01

Strain SP3 revealed the abilty to utilizes emulsifier which is widely used in the preparation of drugs, vaccines, food, cosmetics and skin care products as its sole carbon and energy source. Generation time ranges from 1.4 to 2.1 h on the polysorbate family. Strain was identified as Acinetobacter baumannii based on 16S rRNA gene and it could dispose 27 % polysorbate 80 within a day. The proposed mechanism for polysorbate utilization belongs to the β-oxidation.

Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber.

PubMed

Choi, Yun-Sang; Kim, Young-Boong; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Park, Jinhee; Kim, Cheon-Jei

2015-01-01

This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back fat+3% BRF), T4 (30% back fat+6% BRF), and T15 (10% back fat+10% canola oil+2% BRF). Lower emulsion stability and higher apparent viscosity were observed in T1, T2, T3, T4, and T8 (20% back fat+3% BRF) compared to the control. Lower emulsion stability and higher hardness was detected in all treatments compared with the control, except T5 (20% back fat), T10 (10% back fat+10% canola oil+2% BRF), T11 (10% back fat+10% olive oil+2% BRF), T12 (10% back fat+10% grape seed oil+2% BRF), and T13 (10% back fat+10% soybean oil+2% BRF). This approach has been found particularly useful for highlighting differences among the emulsified properties in emulsion meat products. Thus, the results obtained with emulsion mapping are useful in making emulsified meat products of desired quality characteristics, partially replacing pork back fat with a mix of 10% back fat, 10% canola oil and 2% BRF was most similar to the control with 30% pork back fat.

Emulsion Mapping in Pork Meat Emulsion Systems with Various Lipid Types and Brown Rice Fiber

PubMed Central

Choi, Yun-Sang; Kim, Young-Boong; Park, Jinhee

2015-01-01

This study was conducted to evaluate emulsion mapping between emulsion stability and cooking yields, apparent viscosity, and hardness of reduced-fat pork emulsion systems. The reduced-fat emulsion systems were supplemented with different lipid types and brown rice bran fiber (BRF) concentrations. Compared to the control with 30% back fat, lower emulsion stability and higher cooking yield of meat emulsion systems were observed in T1 (30% back fat+1% BRF), T2 (30% back fat+2% BRF), T3 (30% back fat+3% BRF), T4 (30% back fat+6% BRF), and T15 (10% back fat+10% canola oil+2% BRF). Lower emulsion stability and higher apparent viscosity were observed in T1, T2, T3, T4, and T8 (20% back fat+3% BRF) compared to the control. Lower emulsion stability and higher hardness was detected in all treatments compared with the control, except T5 (20% back fat), T10 (10% back fat+10% canola oil+2% BRF), T11 (10% back fat+10% olive oil+2% BRF), T12 (10% back fat+10% grape seed oil+2% BRF), and T13 (10% back fat+10% soybean oil+2% BRF). This approach has been found particularly useful for highlighting differences among the emulsified properties in emulsion meat products. Thus, the results obtained with emulsion mapping are useful in making emulsified meat products of desired quality characteristics, partially replacing pork back fat with a mix of 10% back fat, 10% canola oil and 2% BRF was most similar to the control with 30% pork back fat. PMID:26761836

Biosurfactant production by Pseudomonas fluorescens growing on molasses and its application in phenol degradation

NASA Astrophysics Data System (ADS)

Suryantia, Venty; Marliyana, Soerya Dewi; Wulandari, Astri

2015-12-01

A molasses based medium for the biosurfactant production by Pseudomonas fluorescens was developed, where the effect of pre-treated of molasses and medium composition were evaluated. Biosurfactant production was followed by measuring optical density (OD), surface tension and emulsifying index (E24) over 12 days of fermentation. The optimum condition for the biosurfactant production was obtained when a medium containing of 8 g/L nutrient broth, 5 g/L NaCl, 1 g/L NH4NO3 and 5% v/v pre-treated molasses with centrifugation was used as media with 3 days of fermentation. The biosurfactant was identified as a rhamnolipid type biosurfactant which had critical micelle concentration (CMC) value of 801 mg/L and was able to reduce the surface tension of the water from 80 mN/m to 51 mN/m. The biosurfactants had water in oil (w/o) emulsion type. Biosurfactant was able to emulsify various hydrocarbons, which were able to decrase the interfacial tension about 50-75% when benzyl chloride, anisaldehyde and palm oil were used as immiscible compounds. The biosurfactant exhibited the E24 value of about 50% and the stable emulsion was reached up to 30 days when lubricant was used as an immiscible compound. Up to 68% of phenol was degraded in the presence of biosurfactant within 15 days, whereas only 56% of phenol was degraded in the absence of biosurfactant. Overall, the results exhibited that molasses are recommended for the rhamnolipids production which possessed good surface-active properties and had potential application in the enhancement of phenol degradation.

Iron mineralization at the Songhu deposit, Chinese Western Tianshan: a type locality with regional metallogenic implications

NASA Astrophysics Data System (ADS)

Wang, Chun-Long; Wang, Yi-Tian; Dong, Lian-Hui; Qin, Ke-Zhang; Evans, Noreen J.; Zhang, Bing; Ren, Yi

2018-01-01

Hosted by volcaniclastics of the Carboniferous Dahalajunshan Formation, the Songhu iron deposit is located in the central segment of the Awulale metallogenic belt, Chinese Western Tianshan. Mineralization and alteration are structurally controlled by orogen-parallel NWW-striking faults. Integrating with mineralogical and stable isotopic analyses based on paragenetic relationships, two types of iron mineralization have been identified. The deuteric mineralization (Type I) represented by brecciated, banded, and disseminated-vein ores juxtaposed with potassic-calcic alteration in the inner zone, which was formed from a magmatic fluid generated during the late stages of regional volcanism. In contrast, the volcanic-hydrothermal mineralization (Type II) is characterized by hydrothermal features occurring in massive and agglomerated ores with abundant sulfides, and was generated from the magmatic fluid with seawater contamination. Two volcaniclastic samples from the hanging and footwall of the main orebody yield zircon U-Pb ages of 327.8 ± 3.1 and 332.0 ± 2.0 Ma, respectively, which indicate Middle Carboniferous volcanism. Timing for iron mineralization can be broadly placed in the same epoch. By reviewing geological, mineralogical, and geochemical features of the primary iron deposits in the Awulale metallogenic belt, we propose that the two types of iron mineralization in the Songhu iron deposit are representative regionally. A summary of available geochronological data reveals Middle-Late Carboniferous polycyclic ore-related volcanism, and nearly contemporaneous iron mineralization along the belt. Furthermore, petro-geochemistry of volcanic-volcaniclastic host rocks indicates that partial melting of a metasomatized mantle wedge under a continental arc setting could have triggered the continuous volcanic activities and associated metallogenesis.

HFE gene mutations and Wilson's disease in Sardinia.

PubMed

Sorbello, Orazio; Sini, Margherita; Civolani, Alberto; Demelia, Luigi

2010-03-01

Hypocaeruloplasminaemia can lead to tissue iron storage in Wilson's disease and the possibility of iron overload in long-term overtreated patients should be considered. The HFE gene encodes a protein that is intimately involved in intestinal iron absorption. The aim of this study was to determine the prevalence of the HFE gene mutation, its role in iron metabolism of Wilson's disease patients and the interplay of therapy in copper and iron homeostasis. The records of 32 patients with Wilson's disease were reviewed for iron and copper indices, HFE gene mutations and liver biopsy. Twenty-six patients were negative for HFE gene mutations and did not present significant alterations of iron metabolism. The HFE mutation was significantly associated with increased hepatic iron content (P<0.02) and transferrin saturation index (P<0.03). After treatment period, iron indices were significantly decreased only in HFE gene wild-type. The HFE gene mutations may be an addictional factor in iron overload in Wilson's disease. Our results showed that an adjustment of dosage of drugs could prevent further iron overload induced by overtreatment only in patients HFE wild-type. 2009. Published by Elsevier Ltd.

A Pseudomonas T6SS effector recruits PQS-containing outer membrane vesicles for iron acquisition

PubMed Central

Lin, Jinshui; Zhang, Weipeng; Cheng, Juanli; Yang, Xu; Zhu, Kaixiang; Wang, Yao; Wei, Gehong; Qian, Pei-Yuan; Luo, Zhao-Qing; Shen, Xihui

2017-01-01

Iron sequestration by host proteins contributes to the defence against bacterial pathogens, which need iron for their metabolism and virulence. A Pseudomonas aeruginosa mutant lacking all three known iron acquisition systems retains the ability to grow in media containing iron chelators, suggesting the presence of additional pathways involved in iron uptake. Here we screen P. aeruginosa mutants defective in growth in iron-depleted media and find that gene PA2374, proximal to the type VI secretion system H3 (H3-T6SS), functions synergistically with known iron acquisition systems. PA2374 (which we have renamed TseF) appears to be secreted by H3-T6SS and is incorporated into outer membrane vesicles (OMVs) by directly interacting with the iron-binding Pseudomonas quinolone signal (PQS), a cell–cell signalling compound. TseF facilitates the delivery of OMV-associated iron to bacterial cells by engaging the Fe(III)-pyochelin receptor FptA and the porin OprF. Our results reveal links between type VI secretion, cell–cell signalling and classic siderophore receptors for iron acquisition in P. aeruginosa. PMID:28348410

Microstructural, textural, and sensory properties of whole-wheat noodle modified by enzymes and emulsifiers.

PubMed

Niu, Meng; Hou, Gary G; Kindelspire, Julie; Krishnan, Padmanaban; Zhao, Siming

2017-05-15

With the utilization of enzymes including endoxylanase, glucose oxidase (GOX) and transglutaminase (TG), and emulsifiers comprising sodium stearoyl lactate (SSL) and soy lecithin, the microstructural, textural, and sensory properties of whole-wheat noodle (WWN) were modified. The development time and stability of whole-wheat dough (WWD) were enhanced by TG due to the formation of a more compact gluten network, and by SSL resulting from the enhanced gluten strength. Microstructure graphs by scanning electron microscopy (SEM) verified that TG and SSL promoted the connectivity of gluten network and the coverage of starch granules in WWN. TG increased the hardness and elasticity of cooked WWN, while two emulsifiers increased the noodle cohesiveness. Additionally, TG and SSL improved the sensory properties of noodle such as bite, springiness, and mouth-feel. The results suggest that TG and SSL are effective ingredients in enhancing the gluten strength of WWD and improving the qualities of WWN. Copyright © 2016 Elsevier Ltd. All rights reserved.

Polycyclic aromatic hydrocarbon-emulsifier protein produced by Aspergillus brasiliensis (niger) in an airlift bioreactor following an electrochemical pretreatment.

PubMed

Sánchez-Vázquez, Victor; Shirai, Keiko; González, Ignacio; Gutiérrez-Rojas, Mariano

2018-05-01

An emulsifier protein (EP) was produced and easily separated from oil-contaminated water as an economical substrate when Aspergillus brasiliensis, pretreated in a solid state culture with a controlled electric field, was used in an airlift bioreactor. The hydrocarbon-EP comprised 19.5% of the total protein, its purification enhanced the specific emulsifying activity (EA) seven times. The influence of operational conditions (pH and salt concentration) on the EA were assessed to characterise the emulsion stability. The EA was increased by 19% in alkaline environments (pH 7-11), but it was not affected by the presence of salt (0-35 g L -1 ). On the other hand, preheating the EP samples (60 °C) enhanced the EA by 2.5 times. Based on analysis of its EA, this EP can be applied as a bioremediation enhancer in contaminated soils. Copyright © 2018 Elsevier Ltd. All rights reserved.

Changes of lipid and fatty acid absorption induced by high dose of citric acid ester and lecithin emulsifiers.

PubMed

Sadouki, Mohamed; Bouchoucha, Michel

2014-09-01

To describe the effect of two food emulsifiers, lecithin (E322) and citric acid esters of mono-and diglycerides of fatty acids (E472c), on the intestinal absorption of lipids. The experiment was conducted on 24 male Wistar rats randomly assigned in three groups. For two groups of six rats, 30% of the lipid intake was replaced with lecithin (L) or citric acid ester of mono and diglycerides, (E); the remaining 12 rats were the control group (C). Diet and fecal fat analysis was used to determine the apparent lipid absorption (ALA) and fatty acids. ALA was significantly lower in the group E than in the groups C and L (p < 0.001). ALA of long saturated chain fatty acids decreased while the length of the carbon chains increased, and this decrease was higher in the group E. E472c emulsifier decreased the intestinal absorption of lipids.

Effects of emulsifier addition on the crystallization and melting behavior of palm olein and coconut oil.

PubMed

Maruyama, Jessica Mayumi; Soares, Fabiana Andreia Schafer De Martini; D'Agostinho, Natalia Roque; Gonçalves, Maria Inês Almeida; Gioielli, Luiz Antonio; da Silva, Roberta Claro

2014-03-12

Two commercial emulsifiers (EM1 and EM2), containing predominantly monoacylglycerols (MAGs), were added in proportiond of 1.0 and 3.0% (w/w) to coconut oil and palm olein. EM1 consisted of approximately 90% MAGs, whereas EM2 consisted of approximately 50% MAGs. The crystallization behavior of these systems was evaluated by differential scanning calorimetry (DSC) and microscopy under polarized light. On the basis of DSC results, it was clear that the addition of EM2 accelerated the crystallization of coconut oil and delayed the crystallization of palm olein. In both oils EM2 addition led to the formation of smaller spherulites, and these effects improved the possibilities for using these fats as ingredients. In coconut oil the spherulites were maintained even at higher temperatures (20 °C). The addition of EM1 to coconut oil changed the crystallization pattern. In palm olein, the addition of 3.0% (w/w) of this emulsifier altered the pattern of crystallization of this fat.

Effect of tartarate and citrate based food additives on the micellar properties of sodium dodecylsulfate for prospective use as food emulsifier.

PubMed

Banipal, Tarlok S; Kaur, Harjinder; Kaur, Amanpreet; Banipal, Parampaul K

2016-01-01

Citrate and tartarate based food preservatives can be used to enhance the emulsifying properties of sodium dodecylsulfate (SDS) based micellar system and thus making it appropriate for food applications. Exploration of interactions between the two species is the key constraint for execution of such ideas. In this work various micellar and thermodynamic parameters of SDS like critical micellar concentration (CMC), standard Gibbs free energy of micellization (ΔG(0)mic.) etc. have been calculated in different concentrations of disodium tartarate (DST) and trisodium citrate (TSC) in the temperature range (288.15-318.15)K from the conductivity and surface tension measurements. The parameters obtained from these studies reveal the competitive nature of both the additives with SDS for available positions at the air/water interface. TSC is found to be more effective additive in order to make SDS micellar system better for its potential applications as food emulsifier. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of microstructure and surface features on wetting angle of a Fe-3.2 wt%C.E. cast iron with water

NASA Astrophysics Data System (ADS)

Riahi, Samira; Niroumand, Behzad; Dorri Moghadam, Afsaneh; Rohatgi, Pradeep K.

2018-05-01

In the present study, variation in surface wetting behavior of a hypoeutectic cast iron with its microstructural features and surface roughness was investigated. Samples with an identical composition, i.e. Fe-3.2 wt%C.E., and different microstructures (a gray cast iron with A-type flake graphite and a white cast iron) were fabricated by gravity casting of molten cast iron in a chill mold at different cooling rates. A variation of surface roughness was also developed by polishing, a four-stage electroetching and a four-stage mechanical abrading on the samples. Roughness and water contact angles of all surfaces were then measured. The surface roughness factor and the solid fraction in contact with water by the Wenzel and Cassie-Baxter contact models were also calculated and compared with the corresponding measured contact angles to find out which regime was active. Results indicated that the surface microstructure and the type of constituents present at the surface influenced the cast iron surface wettability and that it was possible to change the surface contact angle by modification of the surface microstructure. The mechanically abraded gray cast iron followed the Wenzel-type regime while the electroetched surfaces of gray cast iron exhibited a transition from Wenzel to Cassie-Baxter type regime. In white cast iron, the results indicated Wenzel type behavior in the electroetched samples while for the mechanically abraded samples, none of these two models could predict the wetting behavior. Furthermore, the wetting angles of both gray and white cast irons were measured after 1, 2, 3 and 4 weeks of air exposure. The results showed that the wetting angles of both samples increased to above 90° after one week of air exposure which was likely due to adsorption of low surface energy hydrocarbons on the surfaces.

Enhanced absorption of indomethacin after oral or rectal administration of a self-emulsifying system containing indomethacin to rats.

PubMed

Kim, J Y; Ku, Y S

2000-01-20

A self-emulsifying system (SES), a mixture of an oil and a surfactant which forms an oil-in-water emulsion, is expected to improve the in vitro drug dissolution and enhance the in vivo drug absorption. In this study, a poorly water-soluble drug, indomethacin (IDM) was incorporated into the SES to increase bioavailability. The SES with 30% of Tween 85 and 70% of ethyl oleate, EO (w/w) was selected as an optimized formulation (high drug loading, low surfactant concentration, and small particle size). After an oral administration of the SES containing IDM and IDM suspension, (IDM was suspended in methyl cellulose), 22.5 mg/kg as IDM, to rats, the area under the plasma concentration-time curve from time zero to the last measured time in plasma, 12 h (AUC(0-12 h)) was significantly greater (57% increase) in the SES, suggesting that oral absorption of IDM increased significantly by the SES. After a rectal administration of gelatin hollow type suppositories, filled with the SES containing IDM and IDM powder physically mixed with the SES, 22. 5 mg/kg, to rats, the AUC(0-12 h) also increased significantly (41% increase) by the SES, suggesting that rectal absorption of IDM also increased significantly by the SES.

Effect of the degree of substitution of octenyl succinic anhydride-banana starch on emulsion stability.

PubMed

Bello-Pérez, Luis A; Bello-Flores, Christopher A; Nuñez-Santiago, María del Carmen; Coronel-Aguilera, Claudia P; Alvarez-Ramirez, J

2015-11-05

Banana starch was esterified with octenylsuccinic anhydride (OSA) at different degree substitution (DS) and used to stabilize emulsions. Morphology, emulsion stability, emulsification index, rheological properties and particle size distribution of the emulsions were tested. Emulsions dyed with Solvent Red 26 showed affinity for the oil phase. Backscattering light showed three regions in the emulsion where the emulsified region was present. Starch concentration had higher effect in the emulsification index (EI) than the DS used in the study because similar values were found with OSA-banana and native starches. However, OSA-banana presented greater stability of the emulsified region. Rheological tests in emulsions with OSA-banana showed G'>G" values and low dependence of G' with the frequency, indicating a dominant elastic response to shear. When emulsions were prepared under high-pressure conditions, the emulsions with OSA-banana starch with different DS showed a bimodal distribution of particle size. The emulsion with OSA-banana starch and the low DS showed similar mean droplet diameter than its native counterpart. In contrast, the highest DS led to the highest mean droplet diameter. It is concluded that OSA-banana starch with DS can be used to stabilize specific emulsion types. Copyright © 2015 Elsevier Ltd. All rights reserved.

Association of TMPRSS6 polymorphisms with ferritin, hemoglobin, and type 2 diabetes risk in a Chinese Han population.

PubMed

Gan, Wei; Guan, Yu; Wu, Qian; An, Peng; Zhu, Jingwen; Lu, Ling; Jing, Li; Yu, Yu; Ruan, Sheng; Xie, Dong; Makrides, Maria; Gibson, Robert A; Anderson, Gregory J; Li, Huaixing; Lin, Xu; Wang, Fudi

2012-03-01

Transmembrane protease serine 6 (TMPRSS6) regulates iron homeostasis by inhibiting the expression of hepcidin. Multiple common variants in TMPRSS6 were significantly associated with serum iron in recent genome-wide association studies, but their effects in the Chinese remain to be elucidated. The objective was to determine whether the TMPRSS6 single nucleotide polymorphisms (SNPs) rs855791(V736A) and rs4820268(D521D) were associated with blood hemoglobin and plasma ferritin concentrations and risk of type 2 diabetes in Chinese individuals. The SNPs rs855791(V736A) and rs4820268(D521D) in the TMPRSS6 gene were genotyped and tested for their associations with plasma iron and type 2 diabetes risk in 1574 unrelated Chinese Hans from Beijing. The 2 TMPRSS6 SNPs rs855791(V736A) and rs4820268(D521D) were both significantly associated with plasma ferritin (P ≤ 0.0058), hemoglobin (P ≤ 0.0013), iron overload risk (P ≤ 0.0068), and type 2 diabetes risk (P ≤ 0.0314). None of the associations with hemoglobin or plasma ferritin remained significant (P ≥ 0.1229) when the 2 variants were both included in one linear regression model. A haplotype carrying both iron-lowering alleles from the 2 TMPRSS SNPs showed significant associations with lower hemoglobin (P = 0.0014), lower plasma ferritin (P = 0.0027), and a reduced risk of iron overload (P = 0.0017) and of type 2 diabetes (P = 0.0277). These findings suggest that TMPRSS6 variants were significantly associated with plasma ferritin, hemoglobin, risk of iron overload, and type 2 diabetes in Chinese Hans. The type 2 diabetes risk conferred by the TMPRSS6 SNPs is possibly mediated by plasma ferritin.

Implications of interfacial characteristics of food foaming agents in foam formulations.

PubMed

Rodríguez Patino, Juan M; Carrera Sánchez, Cecilio; Rodríguez Niño, Ma Rosario

2008-08-05

The manufacture of food dispersions (emulsions and foams) with specific quality attributes depends on the selection of the most appropriate raw materials and processing conditions. These dispersions being thermodynamically unstable require the use of emulsifiers (proteins, lipids, phospholipids, surfactants etc.). Emulsifiers typically coexist in the interfacial layer with specific functions in the processing and properties of the final product. The optimum use of emulsifiers depends on our knowledge of their interfacial physico-chemical characteristics - such as surface activity, amount adsorbed, structure, thickness, topography, ability to desorb (stability), lateral mobility, interactions between adsorbed molecules, ability to change conformation, interfacial rheological properties, etc. -, the kinetics of film formation and other associated physico-chemical properties at fluid interfaces. These monolayers constitute well defined systems for the analysis of food colloids at the micro- and nano-scale level, with several advantages for fundamental studies. In the present review we are concerned with the analysis of physico-chemical properties of emulsifier films at fluid interfaces in relation to foaming. Information about the above properties would be very helpful in the prediction of optimised formulations for food foams. We concluded that at surface pressures lower than that of monolayer saturation the foaming capacity is low, or even zero. A close relationship was observed between foaming capacity and the rate of diffusion of the foaming agent to the air-water interface. However, the foam stability correlates with the properties of the film at long-term adsorption.

Preparation of Nanoemulsions by Premix Membrane Emulsification: Which Parameters Have a Significant Influence on the Resulting Particle Size?

PubMed

Gehrmann, Sandra; Bunjes, Heike

2017-08-01

Oil-in-water emulsions with particle sizes smaller than 200 nm are interesting carrier systems for poorly water-soluble drugs. Such emulsions can be produced by premix membrane emulsification. In this study, it was systematically investigated which process and formulation parameters have a strong influence on the resulting quality of a triglyceride emulsion. The influence of the pre-emulsion quality and the emulsifier concentration was examined. Also a design of experiments (DoE) approach was carried out: variables included were emulsifier (poloxamer 188, Tween 80, and sucrose laurate [SL]), flow rate, cycle number, and membrane material (polyester, nylon, cellulose acetate, and aluminum oxide; pore sizes, 200 nm), and responses were d 50 value and span for particle size and distribution width. The quality of the pre-emulsion had no influence on the quality of the nanoemulsion after 5 extrusion cycles. The DoE evaluation indicated that an increase in flow rate was of minor importance, whereas an increase in cycle number had a strong impact on the decrease of particle size. The very hydrophilic alumina membrane in combination with the emulsifier which caused the lowest interfacial tension (SL) was the most suitable combination. However, in general, the favorable emulsifier was membrane dependent. Even smaller particle sizes (∼100 nm) could be achieved by using an alumina membrane with smaller pore sizes (100 nm). Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

A novel sample preparation method using rapid nonheated saponification method for the determination of cholesterol in emulsified foods.

PubMed

Jeong, In-Seek; Kwak, Byung-Man; Ahn, Jang-Hyuk; Leem, Donggil; Yoon, Taehyung; Yoon, Changyong; Jeong, Jayoung; Park, Jung-Min; Kim, Jin-Man

2012-10-01

In this study, nonheated saponification was employed as a novel, rapid, and easy sample preparation method for the determination of cholesterol in emulsified foods. Cholesterol content was analyzed using gas chromatography with a flame ionization detector (GC-FID). The cholesterol extraction method was optimized for maximum recovery from baby food and infant formula. Under these conditions, the optimum extraction solvent was 10 mL ethyl ether per 1 to 2 g sample, and the saponification solution was 0.2 mL KOH in methanol. The cholesterol content in the products was determined to be within the certified range of certified reference materials (CRMs), NIST SRM 1544 and SRM 1849. The results of the recovery test performed using spiked materials were in the range of 98.24% to 99.45% with an relative standard devitation (RSD) between 0.83% and 1.61%. This method could be used to reduce sample pretreatment time and is expected to provide an accurate determination of cholesterol in emulsified food matrices such as infant formula and baby food. A novel, rapid, and easy sample preparation method using nonheated saponification was developed for cholesterol detection in emulsified foods. Recovery tests of CRMs were satisfactory, and the recoveries of spiked materials were accurate and precise. This method was effective and decreased the time required for analysis by 5-fold compared to the official method. © 2012 Institute of Food Technologists®

Development of solid self-emulsifying drug delivery system (SEDDS) I: use of poloxamer 188 as both solidifying and emulsifying agent for lipids.

PubMed

Shah, Ankita V; Serajuddin, Abu T M

2012-10-01

To develop solid self-emulsifying drug delivery systems (SEDDS) for lipids using poloxamer 188 as both solidifying and emulsifying agents. Mixtures of various lipids with poloxamer 188 and PEG 8000 were prepared at ~75°C. The molten mixtures, with and without dissolved drugs (fenofibrate and probucol), were then cooled to room temperature. When solids formed, they were characterized by powder XRD, DSC, microscopy using cross-polarization and confocal fluorescence techniques, dispersion test in water and particle size analysis of dispersions. When mixed with poloxamer 188 or PEG 8000, lipids consisting of monoesters of fatty acids with glycerol or propylene glycol formed solid systems, but not di- and tri-esters, which showed phase separation. Added to water, the solid systems containing poloxamer 188 started to disperse in water forming oil globules of 200-600 nm. No emulsification of lipids was observed from solids containing PEG 8000, indicating that the surfactant property of poloxamer 188 was responsible for emulsification. Powder XRD, DSC and microscopic examination revealed that poloxamer 188 and PEG 8000 maintained their crystallinity in solid systems, while the lipids were interspersed in between crystalline regions. The drug remained solubilized in the lipid phase. A novel solid SEDDS is developed where the drug can be solubilized in liquid lipids and then the lipidic solution can be converted to solid mass by dispersing into the microstructure of poloxamer 188.

Biopharmaceutical insights of particulate emulsified systems - a prospective overview.

PubMed

Katamreddy, Jyothshna Devi; Yalavarthi, Prasanna Raju; D, Subba Rao; Battu, Sowjanya; Peesa, Jaya Preethi

2018-05-10

During the twenty-first century, drug discovery is expanding rapidly and a large number of chemical moieties are recognized. Many of them are poorly soluble and hence related biopharmaceutical constraints are to be addressed systematically. Among novel approaches to resolving biopharmaceutical issues, micro- and nano-emulsified systems serve as the best strategy for delivering both hydrophobic and hydrophilic drugs owing to their greater solubilization and transportation capabilities. Of late, the unique physical and biopharmaceutical properties of these liquid isotropic homogenous systems have gained substantive research importance. In addition nano/micro lipid systems share structural and functional similarity with that of the physiological lipids which offer better tolerance ability in the body. In this context, this article provides information on the historical emergence of particulate emulsified systems, importance and rationale of selection of carriers. It also encompasses the physicochemical principles that are responsible for the elevation of therapeutic outcomes of delivery systems. Detailed and schematic absorption of these drug delivery systems is explained here. Gastro-intestinal biochemistry necessary in the understanding of digestion process, lipolytic products formed, micellar structures, enzymes, transporters, mechanism of cell uptake involved after subsequent oral absorption are also emphasized. In addition, this article also explains disposition and pharmacokinetic properties of emulsified systems with real-time therapeutic research outcomes. The influence of biochemical compositions and biopharmaceutical principles on absorption and disposition patterns of ME/NEs was described in the article for the interest of readers and young researchers.

Fabrication and Properties of Micro-Nanoencapsulated Phase Change Materials for Internally-Cooled Liquid Desiccant Dehumidification

PubMed Central

Niu, Xiaofeng; Xu, Qing; Zhang, Yi; Zhang, Yue; Yan, Yufeng; Liu, Tao

2017-01-01

Micro-nanoencapsulated phase change materials (M-NEPCMs) are proposed to be useful in liquid desiccant dehumidification by restraining the temperature rise in the moisture-removal process and improving the dehumidification efficiency. In this paper, the n-octadecane M-NEPCMs with desirable thermal properties for internally-cooled dehumidification were fabricated by using compound emulsifiers through the in-situ polymerization method. Melamine-formaldehyde resin was used as the shell material. The effects of the mixing ratio, emulsification methods and amount of the compound emulsifiers on the morphology, size and thermal properties of the M-NEPCMs were investigated experimentally. The optimum weight mixing ratio of the compound emulsifiers is SDS (sodium dodecyl sulfate):Tween80 (polyoxyethylene sorbitan monooleate):Span80 (sorbitan monooleate) = 0.1:0.6:0.3, which achieves the best stability of the n-octadecane emulsion. When the compound emulsifiers are 10 wt. % of the core material, the melting enthalpy of M-NEPCMs reaches its maximum of 145.26 J/g of capsules, with an encapsulation efficiency of 62.88% and a mean diameter of 636 nm. The sub-cooling of the prepared M-NEPCMs is lower than 3 °C, with an acceptable thermal reliability after the thermal cycling test. A pre-emulsification prior to the addition of deionized water in the emulsification is beneficial to the morphology of the capsules, as the phase change enthalpy can be increased by 123.7%. PMID:28468282

[Study on self-microemulsifying membrane controlled-release drop pill of hawthorn leaves flavonoids].

PubMed

Wang, Jin-Xuan; Huang, Hong-Zhang; Li, Ning; Gao, Chong-Kai

2014-03-01

To prepare the hawthorn leaves flavonoids self-microemulsifying membrane controlled-release coated drop pill, and to study its release rate in vitro and pharmacokinetics study in vivo. In order to improve the dissolution of hawthorn leaves flavonoids, self-microemulsifying technology was used to prepare the hawthorn leaves flavonoids self-microemulsion. Hawthorn leaves flavonoids self-microemulsifying drop pill was prepared with the PEG 6000. Studies were made on the in vitro release of flavonoids from hawthorn leaves self-micro-emulsifying membrane-moderated coated drop pills and the in vivo pharmacokinetic in rats. The prescription of flavonoids from hawthorn leaves self-micro-emulsifying drop pills was 0.25 g of flavonoids from hawthorn leaves, 0.25 g of iodophenyl maleimide, 0.375 g of polyethylene glycol 400, 0.375 g of cremophor RH 40 and 2 g of polyethylene glycol 6000. The optimized prescription was 4 g of ethyl cellulose 20, 0.64 g of polyethylene glycol 400, 1.8 g of diethyl phthalate, and the weight of coating materials increased by 3.5%. Flavonoids from hawthorn leaves self-micro-emulsifying membrane-moderated coated drop pills complied with the design of sustained-release in 12 h in terms of in vitro release and in vivo pharmacokinetic parameters in rats, and its bioavailability was 2.47 times of quick-release drop pills. Slightly soluble flavonoids from hawthorn leaves could be made into sustained-release preparations by the self-micro-emulsifying and coating technology.

Cellular iron transport.

PubMed

Garrick, Michael D; Garrick, Laura M

2009-05-01

Iron has a split personality as an essential nutrient that also has the potential to generate reactive oxygen species. We discuss how different cell types within specific tissues manage this schizophrenia. The emphasis in enterocytes is on regulating the body's supply of iron by regulating transport into the blood stream. In developing red blood cells, adaptations in transport manage the body's highest flux of iron. Hepatocytes buffer the body's stock of iron. Macrophage recycle the iron from effete red cells among other iron management tasks. Pneumocytes provide a barrier to prevent illicit entry that, when at risk of breaching, leads to a need to handle the dangers in a fashion essentially shared with macrophage. We also discuss or introduce cell types including renal cells, neurons, other brain cells, and more where our ignorance, currently still vast, needs to be removed by future research.

Higher bioavailability of iron from whole wheat bread compared with iron-fortified white breads in caco-2 cell model: an experimental study.

PubMed

Nikooyeh, Bahareh; Neyestani, Tirang R

2017-06-01

Bread, as the staple food of Iranians, with average per capita consumption of 300 g d -1 , could potentially be a good vehicle for many fortificants, including iron. In this study, iron bioavailability from flat breads (three fortified and one whole wheat unfortified) was investigated using in vitro simulation of gastrointestinal digestion and absorption in a caco-2 cell model. Despite having a lower ferritin/protein ratio in comparison with fortified breads, whole wheat bread showed higher iron bioavailability than the other three types of bread. Assuming iron bioavailability from the ferrous sulfate supplement used as standard was about 10%, the estimated bioavailability of iron from the test breads was calculated as 5.0-8.0%. Whole wheat bread (∼8%), as compared with the fortified breads (∼5-6.5%), had higher iron bioavailability. Iron from unfortified whole wheat bread is more bioavailable than from three types of iron-fortified breads. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Hfe Deficiency Impairs Pulmonary Neutrophil Recruitment in Response to Inflammation

PubMed Central

Benesova, Karolina; Vujić Spasić, Maja; Schaefer, Sebastian M.; Stolte, Jens; Baehr-Ivacevic, Tomi; Waldow, Katharina; Zhou, Zhe; Klingmueller, Ursula; Benes, Vladimir; Mall, Marcus A.; Muckenthaler, Martina U.

2012-01-01

Regulation of iron homeostasis and the inflammatory response are tightly linked to protect the host from infection. Here we investigate how imbalanced systemic iron homeostasis in a murine disease model of hereditary hemochromatosis (Hfe−/− mice) affects the inflammatory responses of the lung. We induced acute pulmonary inflammation in Hfe−/− and wild-type mice by intratracheal instillation of 20 µg of lipopolysaccharide (LPS) and analyzed local and systemic inflammatory responses and iron-related parameters. We show that in Hfe−/− mice neutrophil recruitment to the bronchoalveolar space is attenuated compared to wild-type mice although circulating neutrophil numbers in the bloodstream were elevated to similar levels in Hfe−/− and wild-type mice. The underlying molecular mechanisms are likely multifactorial and include elevated systemic iron levels, alveolar macrophage iron deficiency and/or hitherto unexplored functions of Hfe in resident pulmonary cell types. As a consequence, pulmonary cytokine expression is out of balance and neutrophils fail to be recruited efficiently to the bronchoalveolar compartment, a process required to protect the host from infections. In conclusion, our findings suggest a novel role for Hfe and/or imbalanced iron homeostasis in the regulation of the inflammatory response in the lung and hereditary hemochromatosis. PMID:22745741

Diabetes in HFE Hemochromatosis

PubMed Central

Acton, Ronald T.

2017-01-01

Diabetes in whites of European descent with hemochromatosis was first attributed to pancreatic siderosis. Later observations revealed that the pathogenesis of diabetes in HFE hemochromatosis is multifactorial and its clinical manifestations are heterogeneous. Increased type 2 diabetes risk in HFE hemochromatosis is associated with one or more factors, including abnormal iron homeostasis and iron overload, decreased insulin secretion, cirrhosis, diabetes in first-degree relatives, increased body mass index, insulin resistance, and metabolic syndrome. In p.C282Y homozygotes, serum ferritin, usually elevated at hemochromatosis diagnosis, largely reflects body iron stores but not diabetes risk. In persons with diabetes type 2 without hemochromatosis diagnoses, serum ferritin levels are higher than those of persons without diabetes, but most values are within the reference range. Phlebotomy therapy to achieve iron depletion does not improve diabetes control in all persons with HFE hemochromatosis. The prevalence of type 2 diabetes diagnosed today in whites of European descent with and without HFE hemochromatosis is similar. Routine iron phenotyping or HFE genotyping of patients with type 2 diabetes is not recommended. Herein, we review diabetes in HFE hemochromatosis and the role of iron in diabetes pathogenesis in whites of European descent with and without HFE hemochromatosis. PMID:28331855

Major role for FeoB in Campylobacter jejuni ferrous iron acquisition, gut colonization, and intracellular survival.

PubMed

Naikare, Hemant; Palyada, Kiran; Panciera, Roger; Marlow, Denver; Stintzi, Alain

2006-10-01

To assess the importance of ferrous iron acquisition in Campylobacter physiology and pathogenesis, we disrupted and characterized the Fe2+ iron transporter, FeoB, in Campylobacter jejuni NCTC 11168, 81-176, and ATCC 43431. The feoB mutant was significantly affected in its ability to transport 55Fe2+. It accumulated half the amount of iron than the wild-type strain during growth in an iron-containing medium. The intracellular iron of the feoB mutant was localized in the periplasmic space versus the cytoplasm for the wild-type strain. These results indicate that the feoB gene of C. jejuni encodes a functional ferrous iron transport system. Reverse transcriptase PCR analysis revealed the cotranscription of feoB and Cj1397, which encodes a homolog of Escherichia coli feoA. C. jejuni 81-176 feoB mutants exhibited reduced ability to persist in human INT-407 embryonic intestinal cells and porcine IPEC-1 small intestinal epithelial cells compared to the wild type. C. jejuni NCTC 11168 feoB mutant was outcompeted by the wild type for colonization and/or survival in the rabbit ileal loop. The feoB mutants of the three C. jejuni strains were significantly affected in their ability to colonize the chick cecum. And finally, the three feoB mutants were outcompeted by their respective wild-type strains for infection of the intestinal tracts of colostrum-deprived piglets. Taken together, these results demonstrate that FeoB-mediated ferrous iron acquisition contributes significantly to colonization of the gastrointestinal tract during both commensal and infectious relationship, and thus it plays an important role in Campylobacter pathogenesis.

Effect of processing on functional properties of animal blood plasma.

PubMed

Del Hoyo, P; Rendueles, M; Díaz, M

2008-04-01

A number of functional and physical properties such as solubility, foam capacity, emulsifying stability and interfacial tension were compared for standard plasma, plasma decationed by ion exchange and plasma deionized by ultrafiltration (UF). The changes in functional properties can determine the use of a protein as an additive to a food product or invalidate its use. All samples had good functional properties and hence could be used in the formulation of food products. Results showed that ion exchange and UF improved emulsifying capacity while having little effect on the other functional properties.

Microbial biodiversity of Tang and Pirgal mud volcanoes and evaluation of bio-emulsifier and bio-demulsifier activities of Capnophile bacteria.

PubMed

Parsia, Yasaman; Sorooshian, Shahryar

2017-12-01

The data presented in this article is related to the Master thesis; entitled "Survey Aerobic Microbial Diversity Mud Volcanoes in Chabahar and Khash Ports in Southern Iran" by the first author of this article, year 2011, Islamic Azad University, Iran (reference number (Parsia, 2011) [1] of this article). This article shows microbial biodiversity and evaluates bio-emulsifier and bio-demulsifier abilities of capnophile isolates, in order to introduce a superior isolate for the Microbial Enhanced Oil Recovery (MEOR) process in the petrochemical industry.

NGP1-01, a multi-targeted polycyclic cage amine, attenuates brain endothelial cell death in iron overload conditions.

PubMed

Lockman, J A; Geldenhuys, W J; Jones-Higgins, M R; Patrick, J D; Allen, D D; Van der Schyf, C J

2012-12-13

Development and progression of neurodegenerative disorders have, amongst other potential causes, been attributed to a disruption of iron regulatory mechanisms and iron accumulation. Excess extracellular iron may enter cells via nontraditional routes such as voltage-gated calcium channels and N-methyl-d-aspartate (NMDA) receptors leading to intracellular oxidative damage and ultimately mitochondrial failure. Nimodipine, an L-type calcium channel blocker has been shown to reduce iron-induced toxicity in neuronal and brain endothelial cells. Our current study investigates NGP1-01, a multimodal drug acting as an antagonist at both the NMDA receptor and the L-type calcium channel. Our previous studies support NGP1-01 as a promising neuroprotective agent in diseases involving calcium-related excitotoxicity. We demonstrate here that NGP1-01 (1 and 10μM) pretreatment abrogates the effects of iron overload in brain endothelial cells protecting cellular viability. Both concentrations of NGP1-01 were found to attenuate iron-induced reduction in cellular viability to a similar extent, and were statistically significant. To further verify the mechanism, the L-type calcium channel agonist FPL 64176 was administered to promote iron uptake. Addition of NGP1-01 dose-dependently reduced FPL 64176 stimulated uptake of iron. These data support further evaluation of NGP1-01 as a neuroprotective agent, not only in diseases associated with excitotoxicity, but also in those of iron overload. Copyright © 2012 Elsevier B.V. All rights reserved.

Transcriptional Profiling of the Iron Starvation Response in Bordetella pertussis Provides New Insights into Siderophore Utilization and Virulence Gene Expression ▿ §

PubMed Central

Brickman, Timothy J.; Cummings, Craig A.; Liew, Sin-Yee; Relman, David A.; Armstrong, Sandra K.

2011-01-01

Serological studies of patients with pertussis and the identification of antigenic Bordetella pertussis proteins support the hypothesis that B. pertussis perceives an iron starvation cue and expresses multiple iron source utilization systems in its natural human host environment. Furthermore, previous studies using a murine respiratory tract infection model showed that several of these B. pertussis iron systems are required for colonization and persistence and are differentially expressed over the course of infection. The present study examined genome-wide changes in B. pertussis gene transcript abundance in response to iron starvation in vitro. In addition to known iron source utilization genes, we identified a previously uncharacterized iron-repressed cytoplasmic membrane transporter system, fbpABC, that is required for the utilization of multiple structurally distinct siderophores including alcaligin, enterobactin, ferrichrome, and desferrioxamine B. Expression of type III secretion system genes was also found to be upregulated during iron starvation in both B. pertussis strain Tohama I and Bordetella bronchiseptica strain RB50. In a survey of type III secretion system protein production by an assortment of B. pertussis laboratory-adapted and low-passage clinical isolate strains, iron limitation increased the production and secretion of the type III secretion system-specific translocation apparatus tip protein Bsp22 in all Bvg-proficient strains. These results indicate that iron starvation in the infected host is an important environmental cue influencing not only Bordetella iron transport gene expression but also the expression of other important virulence-associated genes. PMID:21742863

Mutations in TMPRSS6 cause iron-refractory iron deficiency anemia (IRIDA)

PubMed Central

Finberg, Karin E; Heeney, Matthew M; Campagna, Dean R; Aydınok, Yeşim; Pearson, Howard A; Hartman, Kip R; Mayo, Mary M; Samuel, Stewart M; Strouse, John J; Markianos, Kyriacos; Andrews, Nancy C; Fleming, Mark D

2011-01-01

Iron deficiency is usually attributed to chronic blood loss or inadequate dietary intake. Here, we show that iron deficiency anemia refractory to oral iron therapy can be caused by germline mutations in TMPRSS6, which encodes a type II transmembrane serine protease produced by the liver that regulates the expression of the systemic iron regulatory hormone hepcidin. These findings demonstrate that TMPRSS6 is essential for normal systemic iron homeostasis in humans. PMID:18408718

Recovery of Iron from Hematite-Rich Diasporic-Type Bauxite Ore

NASA Astrophysics Data System (ADS)

Jiang, Tao; Li, Zhuoxuan; Yang, Lin; Li, Guanghui; Zhang, Yuanbo; Zeng, Jinghua

A technique has been proposed for recovering iron from hematite-rich diasporic-type bauxite ore in this study. Direct reduction roasting followed by low intensity wet magnetic separation process was carried out. The parameters including reduction temperature and time, sodium salts, grinding conditions and magnetic field intensity for separation of iron were determined. The optimum process parameters as follows: roasting temperature of 1050 °C, time of 60 min, sodium salts involving sodium sulfate, borax, sodium carbonate with dosages of 10 wt%, 2 wt%, 35 wt% respectively, and magnetic field intensity of 1000 Gs with fineness of pulp reached 92.75% passing -0.074mm. Under the optimal conditions, an iron concentrate containing 88.17% total iron grade and iron recovery of 92.51% was obtained, 4.55% total iron grade in tailings. This novel technique provide a potential route for utilizing hematiterich diasporic bauxite ore, recovering iron resource firstly, and extracting alumina from magnetic separation tailings further.

Red Meat, Dietary Heme Iron, and Risk of Type 2 Diabetes: The Involvement of Advanced Lipoxidation Endproducts12

PubMed Central

White, Desley L.; Collinson, Avril

2013-01-01

There is growing evidence of disordered iron homeostasis in the diabetic condition, with links proposed between dietary iron intakes and both the risk of disease and the risk of complications of advanced disease. In the United States, Britain, and Canada, the largest dietary contributors of iron are cereals and cereal products and meat and meat products. This review discusses the findings of cohort studies and meta-analyses of heme iron and red meat intakes and the risk of type 2 diabetes. These suggest that processed red meat is associated with increased risk, with high intakes of red meat possibly also associated with a small increased risk. Historically, humans have relied on large quantities of heme iron and red meat in their diets, and therefore it is paradoxical that iron from meat sources should be associated with the risk of type 2 diabetes. A reason for this association may be drawn from studies of dietary advanced glycation and lipoxidation endproducts present in processed food and the mechanisms by which insulin output by pancreatic islet cells might be influenced by the protein modifications present in processed red meat. PMID:23858089

Promising perspectives for ruminal protection of polyunsaturated fatty acids through polyphenol-oxidase-mediated crosslinking of interfacial protein in emulsions.

PubMed

De Neve, N; Vlaeminck, B; Gadeyne, F; Claeys, E; Van der Meeren, P; Fievez, V

2018-03-16

Previously, polyunsaturated fatty acids (PUFA) from linseed oil were effectively protected (>80%) against biohydrogenation through polyphenol-oxidase-mediated protein crosslinking of an emulsion, prepared with polyphenol oxidase (PPO) extract from potato tuber peelings. However, until now, emulsions of only 2 wt% oil have been successfully protected, which implies serious limitations both from a research perspective (e.g. in vivo trials) as well as for further upscaling toward practical applications. Therefore, the aim of this study was to increase the oil/PPO ratio. In the original protocol, the PPO extract served both an emulsifying function as well as a crosslinking function. Here, it was first evaluated whether alternative protein sources could replace the emulsifying function of the PPO extract, with addition of PPO extract and 4-methylcatechol (4MC) to induce crosslinking after emulsion preparation. This approach was then further used to evaluate protection of emulsions with higher oil content. Five candidate emulsifiers (soy glycinin, gelatin, whey protein isolate (WPI), bovine serum albumin and sodium caseinate) were used to prepare 10 wt% oil emulsions, which were diluted five times (w/w) with PPO extract (experiment 1). As a positive control, 2 wt% oil emulsions were prepared directly with PPO extract according to the original protocol. Further, emulsions of 2, 4, 6, 8 and 10 wt% oil were prepared, with 80 wt% PPO extract (experiment 2), or with 90, 80, 70, 60 and 50 wt% PPO extract, respectively (experiment 3) starting from WPI-stabilized emulsions. Enzymatic crosslinking was induced by 24-h incubation with 4MC. Ruminal protection efficiency was evaluated by 24-h in vitro batch simulation of the rumen metabolism. In experiment 1, protection efficiencies were equal or higher than the control (85.5% to 92.5% v. 81.3%). In both experiments 2 and 3, high protection efficiencies (>80%) were achieved, except for emulsions containing 10 wt% oil emulsions (<50% protection), which showed oiling-off after enzymatic crosslinking. This study demonstrated that alternative emulsifier proteins can be used in combination with PPO extract to protect emulsified PUFA-rich oils against ruminal biohydrogenation. By applying the new protocol, 6.5 times less PPO extract was required.

Composition analysis and material characterization of an emulsifying extracellular polysaccharide (EPS) produced by Bacillus megaterium RB-05: a hydrodynamic sediment-attached isolate of freshwater origin.

PubMed

Chowdhury, S R; Manna, S; Saha, P; Basak, R K; Sen, R; Roy, D; Adhikari, B

2011-12-01

This work was aimed to isolate, purify and characterize an extracellular polysaccharide (EPS) produced by a freshwater dynamic sediment-attached micro-organism, Bacillus megaterium RB-05, and study its emulsifying potential in different hydrocarbon media. Bacillus megaterium RB-05 was found to produce EPSs in glucose mineral salts medium, and maximum yield (0.864 g l(-1) ) was achieved after 24-h incubation. The recovery rates of the polysaccharide material by ion-exchange and gel filtration chromatography were around 67 and 93%, respectively. As evident from HPLC and FT-IR analyses, the polysaccharide was found to be a heteropolymer-containing glucose, galactose, mannose, arabinose, fucose and N-acetyl glucosamine. Different oligosaccharide combinations namely hexose(3), hexose(4), hexose(5) deoxyhexose(1) and hexose(5) deoxyhexose(1) pentose(3) were obtained after partial hydrolysis of the polymer using MALDI-ToF-MS. The polysaccharide with an average molecular weight of 170 kDa and thermal stability up to 180°C showed pseudoplastic rheology and significant emulsifying activity in hydrocarbon media. Isolated polysaccharide was found to be of high molecular weight and thermally stable. The purified EPS fraction was composed of hexose, pentose and deoxyhexose sugar residues, which is a rare combination for bacterial polysaccharides. Emulsifying property was either better or comparable to that of other commercially available natural gums and polysaccharides. This is probably one of the few reports about characterizing an emulsifying EPS produced by a freshwater sediment-attached bacterium. The results of this study contribute to understand the influence of chemical composition and material properties of a new microbial polysaccharide on its application in industrial biotechnology. Furthermore, this work reconfirms freshwater dynamic sediment as a potential habitat for bioprospecting extracellular polymer-producing bacteria. This study will improve our knowledge on the exploitation of a nonconventional renewable resource, which also seems to be ecologically significant. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

Stability of anthocyanin-rich w/o/w-emulsions designed for intestinal release in gastrointestinal environment.

PubMed

Frank, Kerstin; Walz, Elke; Gräf, Volker; Greiner, Ralf; Köhler, Karsten; Schuchmann, Heike Petra

2012-12-01

Anthocyanins belong to the most important hydrophilic plant pigments. Outside their natural environment, these molecules are extremely unstable. Encapsulating them in submicron-sized containers is one possibility to stabilize them for the use in bioactivity studies or functional foods. The containers have to be designed for a target release in the human gastrointestinal system. In this contribution, an anthocyanin-rich bilberry extract was encapsulated in the inner aqueous phase of water-in-oil-in-water-double emulsions. The physical stability as well as the release of free fatty acids and encapsulated, bioactive substances from the emulsions during an in vitro gastrointestinal passage were investigated. The focus was on the influence of emulsion microstructural parameters (for example, inner and outer droplet size, disperse phase content) and required additives (emulsifier systems), respectively. It could be shown that it is possible to stabilize anthocyanins in the inner phase of double emulsions. The release rate of free fatty acids during incubation was independent of the emulsifier used. However, the exterior (O/W)-emulsifier has an impact on the stability of multiple emulsions in gastrointestinal environment and, thus, the location of release. Long-chained emulsifiers like whey proteins are most suitable to transport a maximum amount of bioactive substances to the effective location, being the small intestine for anthocyanins. In addition, it was shown that the dominating release mechanism for entrapped matter was coalescence of the interior W(1) -droplets with the surrounding W(2) -phase. © 2012 Institute of Process Engineering in Life Science I: Food Process Engineering, Karlsruhe Institute of Technology (KIT).

Inverse-model estimates of the ocean's coupled phosphorus, silicon, and iron cycles

NASA Astrophysics Data System (ADS)

Pasquier, Benoît; Holzer, Mark

2017-09-01

The ocean's nutrient cycles are important for the carbon balance of the climate system and for shaping the ocean's distribution of dissolved elements. Dissolved iron (dFe) is a key limiting micronutrient, but iron scavenging is observationally poorly constrained, leading to large uncertainties in the external sources of iron and hence in the state of the marine iron cycle. Here we build a steady-state model of the ocean's coupled phosphorus, silicon, and iron cycles embedded in a data-assimilated steady-state global ocean circulation. The model includes the redissolution of scavenged iron, parameterization of subgrid topography, and small, large, and diatom phytoplankton functional classes. Phytoplankton concentrations are implicitly represented in the parameterization of biological nutrient utilization through an equilibrium logistic model. Our formulation thus has only three coupled nutrient tracers, the three-dimensional distributions of which are found using a Newton solver. The very efficient numerics allow us to use the model in inverse mode to objectively constrain many biogeochemical parameters by minimizing the mismatch between modeled and observed nutrient and phytoplankton concentrations. Iron source and sink parameters cannot jointly be optimized because of local compensation between regeneration, recycling, and scavenging. We therefore consider a family of possible state estimates corresponding to a wide range of external iron source strengths. All state estimates have a similar mismatch with the observed nutrient concentrations and very similar large-scale dFe distributions. However, the relative contributions of aeolian, sedimentary, and hydrothermal iron to the total dFe concentration differ widely depending on the sources. Both the magnitude and pattern of the phosphorus and opal exports are well constrained, with global values of 8. 1 ± 0. 3 Tmol P yr-1 (or, in carbon units, 10. 3 ± 0. 4 Pg C yr-1) and 171. ± 3. Tmol Si yr-1. We diagnose the phosphorus and opal exports supported by aeolian, sedimentary, and hydrothermal iron. The geographic patterns of the export supported by each iron type are well constrained across the family of state estimates. Sedimentary-iron-supported export is important in shelf and large-scale upwelling regions, while hydrothermal iron contributes to export mostly in the Southern Ocean. The fraction of the global export supported by a given iron type varies systematically with its fractional contribution to the total iron source. Aeolian iron is most efficient in supporting export in the sense that its fractional contribution to export exceeds its fractional contribution to the total source. Per source-injected molecule, aeolian iron supports 3. 1 ± 0. 8 times more phosphorus export and 2. 0 ± 0. 5 times more opal export than the other iron types. Conversely, per injected molecule, sedimentary and hydrothermal iron support 2. 3 ± 0. 6 and 4. ± 2. times less phosphorus export, and 1. 9 ± 0. 5 and 2. ± 1. times less opal export than the other iron types.

Electrolytic photodissociation of chemical compounds by iron oxide electrodes

DOEpatents

Somorjai, Gabor A.; Leygraf, Christofer H.

1984-01-01

Chemical compounds can be dissociated by contacting the same with a p/n type semi-conductor diode having visible light as its sole source of energy. The diode consists of low cost, readily available materials, specifically polycrystalline iron oxide doped with silicon in the case of the n-type semi-conductor electrode, and polycrystalline iron oxide doped with magnesium in the case of the p-type electrode. So long as the light source has an energy greater than 2.2 electron volts, no added energy source is needed to achieve dissociation.

Electrolytic photodissociation of chemical compounds by iron oxide photochemical diodes

DOEpatents

Somorjai, Gabor A.; Leygraf, Christofer H.

1985-01-01

Chemical compounds can be dissociated by contacting the same with a p/n type semi-conductor photochemical diode having visible light as its sole source of energy. The photochemical diode consists of low cost, readily available materials, specifically polycrystalline iron oxide doped with silicon in the case of the n-type semi-conductor electrode, and polycrystalline iron oxide doped with magnesium in the case of the p-type electrode. So long as the light source has an energy greater than 2.2 electron volts, no added energy source is needed to achieve dissociation.

Uncoupled iron homeostasis in type 2 diabetes mellitus.

PubMed

Altamura, Sandro; Kopf, Stefan; Schmidt, Julia; Müdder, Katja; da Silva, Ana Rita; Nawroth, Peter; Muckenthaler, Martina U

2017-12-01

Diabetes mellitus is frequently associated with iron overload conditions, such as primary and secondary hemochromatosis. Conversely, patients affected by type 2 diabetes mellitus (T2DM) show elevated ferritin levels, a biomarker for increased body iron stores. Despite these documented associations between dysregulated iron metabolism and T2DM, the underlying mechanisms are poorly understood. Here, we show that T2DM patients have reduced serum levels of hepcidin, the iron-regulated hormone that maintains systemic iron homeostasis. Consistent with this finding, we also observed an increase in circulating iron and ferritin levels. Our analysis of db/db mice demonstrates that this model recapitulates the systemic alterations observed in patients. Interestingly, db/db mice show an overall hepatic iron deficiency despite unaltered expression of ferritin and the iron importer TfR1. In addition, the liver correctly senses increased circulating iron levels by activating the BMP/SMAD signaling pathway even though hepcidin expression is decreased. We show that increased AKT phosphorylation may override active BMP/SMAD signaling and decrease hepcidin expression in 10-week old db/db mice. We conclude that the metabolic alterations occurring in T2DM impact on the regulation of iron homeostasis on multiple levels. As a result, metabolic perturbations induce an "iron resistance" phenotype, whereby signals that translate increased circulating iron levels into hepcidin production, are dysregulated. T2DM patients show increased circulating iron levels. T2DM is associated with inappropriately low hepcidin levels. Metabolic alterations in T2DM induce an "iron resistance" phenotype.

Materials processing threshold report: 2. Use of low gravity for cast iron process development

NASA Technical Reports Server (NTRS)

Frankhouser, W. L.

1980-01-01

Potential applications of a low gravity environment of interest to the commercial producers of cast iron were assessed to determine whether low gravity conditions offer potential opportunities to producers for improving cast iron properties and expanding the use of cast irons. The assessment is limited to the gray and nodular types of iron, however, the findings are applicable to all cast irons. The potential advantages accrued through low gravity experiments with cast irons are described.

Structure- and oil type-based efficacy of emulsion adjuvants.

PubMed

Jansen, Theo; Hofmans, Marij P M; Theelen, Marc J G; Manders, Frans; Schijns, Virgil E J C

2006-06-29

Oil-based emulsions are well-known immunopotentiators for inactivated, "killed" vaccines. We addressed the relationship between emulsion structure and levels of in vivo antibody formation to inactivated New Castle Disease virus (NDV) and Infectious Bronchitis virus (IBV) as antigens in 3-week-old chickens. The use of a polymeric emulsifier allowed for direct comparison of three types of emulsions, water-in-oil (W/O), oil-in-water (O/W) and W/O-in-water (W/O/W), while maintaining an identical content of components for each vehicle. They were prepared with either non-metabolizable, mineral oil or metabolizable, Miglyol 840. In addition, we assessed the inherent release capacity of each emulsion variant in vitro. Remarkably, we noted that W/O-type emulsions induced the best immune responses, while they released no antigen during 3 weeks. In general, mineral oil vaccines showed superior efficacy compared to Miglyol 840-based vaccines.

Mercury mine drainage and processes that control its environmental impact

USGS Publications Warehouse

Rytuba, J.J.

2000-01-01

Mine drainage from mercury mines in the California Coast Range mercury mineral belt is an environmental concern because of its acidity and high sulfate, mercury, and methylmercury concentrations. Two types of mercury deposits are present in the mineral belt, silica-carbonate and hot-spring type. Mine drainage is associated with both deposit types but more commonly with the silica-carbonate type because of the extensive underground workings present at these mines. Mercury ores consisting primarily of cinnabar were processed in rotary furnaces and retorts and elemental mercury recovered from condensing systems. During the roasting process mercury phases more soluble than cinnabar are formed and concentrated in the mine tailings, commonly termed calcines. Differences in mineralogy and trace metal geochemistry between the two deposit types are reflected in mine drainage composition. Silica-carbonate type deposits have higher iron sulfide content than hot- spring type deposits and mine drainage from these deposits may have extreme acidity and very high concentrations of iron and sulfate. Mercury and methylmercury concentrations in mine drainage are relatively low at the point of discharge from mine workings. The concentration of both mercury species increases significantly in mine drainage that flows through and reacts with calcines. The soluble mercury phases in the calcines are dissolved and sulfate is added such that methylation of mercury by sulfate reducing bacteria is enhanced in calcines that are saturated with mine drainage. Where mercury mine drainage enters and first mixes with stream water, the addition of high concentrations of mercury and sulfate generates a favorable environment for methylation of mercury. Mixing of oxygenated stream water with mine drainage causes oxidation of dissolved iron(II) and precipitation of iron oxyhydroxide that accumulates in the streambed. Both mercury and methylmercury are strongly adsorbed onto iron oxyhydroxide over the pH range of 3.2-7.1 in streams impacted by mine drainage. The dissolved fraction of both mercury species is depleted and concentrated in iron oxyhydroxide such that the amount of iron oxyhydroxide in the water column reflects the concentration of mercury species. In streams impacted by mine drainage, mercury and methylmercury are transported and adsorbed onto particulate phases. During periods of low stream flow, fine-grained iron hydroxide sediment accumulates in the bed load of the stream and adsorbs mercury and methylmercury such that both forms of mercury become highly enriched in the iron oxyhydroxide sediment. During high-flow events, mercury- and methylmercury-enriched iron hydroxide sediment is transported into larger aquatic systems producing a high flux of bioavailable mercury. (C) 2000 Elsevier Science B.V.

Properties and oxidative stability of emulsions prepared with myofibrillar protein and lard diacylglycerols.

PubMed

Diao, Xiaoqin; Guan, Haining; Zhao, Xinxin; Chen, Qian; Kong, Baohua

2016-05-01

The objective of this study was to investigate the emulsifying properties and oxidative stability of emulsions prepared with porcine myofibrillar proteins (MPs) and different lipids, including lard, glycerolized lard (GL) and purified glycerolized lard (PGL). The GL and PGL emulsions had significantly higher emulsifying activity indices and emulsion stability indices than the lard emulsion (P<0.05). The PGL emulsion presented smaller droplet sizes, thus decreasing particle aggregation and improving emulsion stability. The static and dynamic rheological observations of the emulsions showed that the emulsions had pseudo-plastic behavior, and the PGL emulsion presented a larger viscosity and a higher storage modulus (G') and loss modulus (G'') compared with the other two emulsions (P<0.05). The formation of thiobarbituric acid-reactive substances, carbonyl contents and total sulfhydryl contents was not significantly different between the emulsions with PGL, GL and lard (P<0.05). In general, lard diacylglycerols enhanced emulsifying abilities and had no adverse effects on the oxidation stability of the emulsions prepared with MPs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enzymatic Preparation of a Homologous Series of Long-Chain 6- O-Acylglucose Esters and Their Evaluation as Emulsifiers.

PubMed

Liang, Min-Yi; Chen, Yongsheng; Banwell, Martin G; Wang, Yong; Lan, Ping

2018-04-18

Sugar fatty acid esters are nonionic surfactants that are widely exploited in the food and cosmetics industries, as well as in the oral care and medical supply fields. Accordingly, new methods for their selective synthesis and the "tuning" of their emulsifying properties are of considerable interest. Herein we report simple and irreversible enzymatic esterifications of d-glucose with seven fatty acid vinyl esters. The foaming and emulsifying effects of the resulting 6- O-acylglucose esters were then evaluated. In accord with expectations, when the length of the alkyl side chain associated with the 6- O-acylglucose esters increases, then their hydrophilic-lipophilic balance (HLB) values decrease, while the stabilities of the derived emulsions improve. In order to maintain good foaming properties, alkyl side chains of at least 9 to 11 carbons in length are required. In the first such assays on 6- O-acylglucose esters, most of those described herein are shown to be nontoxic to the HepG2, MCF-7, LNacp, SW549, and LO-2 cell lines.

Online sensing and control of oil in process wastewater

NASA Astrophysics Data System (ADS)

Khomchenko, Irina B.; Soukhomlinoff, Alexander D.; Mitchell, T. F.; Selenow, Alexander E.

2002-02-01

Industrial processes, which eliminate high concentration of oil in their waste stream, find it extremely difficult to measure and control the water purification process. Most oil separation processes involve chemical separation using highly corrosive caustics, acids, surfactants, and emulsifiers. Included in the output of this chemical treatment process are highly adhesive tar-like globules, emulsified and surface oils, and other emulsified chemicals, in addition to suspended solids. The level of oil/hydrocarbons concentration in the wastewater process may fluctuate from 1 ppm to 10,000 ppm, depending upon the specifications of the industry and level of water quality control. The authors have developed a sensing technology, which provides the accuracy of scatter/absorption sensing in a contactless environment by combining these methodologies with reflective measurement. The sensitivity of the sensor may be modified by changing the fluid level control in the flow cell, allowing for a broad range of accurate measurement from 1 ppm to 10,000 ppm. Because this sensing system has been designed to work in a highly invasive environment, it can be placed close to the process source to allow for accurate real time measurement and control.

Influence of hydrophilic surfactants on the properties of multiple W/O/W emulsions.

PubMed

Schmidts, T; Dobler, D; Nissing, C; Runkel, F

2009-10-01

Multiple W/O/W emulsions for topical application using Span 80 as a lipophilic emulsifier were prepared. Several hydrophilic emulsifiers were tested in respect of their suitability for the preparation of multiple emulsions. In addition, the effect of different oil-phase compositions on emulsion stability was investigated. The physicochemical parameters of the formulations were characterized and their long-term stability was evaluated by means of rheological measurements, droplet size observations and conductivity analysis. As discovered, the modification of an oil-phase composition results in a decrease in the diffusion coefficient of water and water-soluble substances and, consequently, in enhanced stability. The influence of the release of electrolytes from the inner to the outer water phase on the emulsion stability behaviour was investigated. It was found, that the effect of the hydrophilic emulsifiers on the formulation properties is related not only to its HLB value, but rather to its chemical composition. As a result, polyethoxylated ethers of fatty alcohols (C=16-18) with HLBs between 15.3 and 16.2 appear to be the most suitable ones for creating stable formulations.

Evaluation of emulsion emulsified by starch nanocrystal: A preliminary study

NASA Astrophysics Data System (ADS)

Ahmad, Azfar Al Ariff; Lazim, Azwan Mat

2018-04-01

The starch nanocrystals (SNC) used in this study were made of sago starch and prepared by using sulfuric acid hydrolysis of sago starch. The aim of this study is to look at the potential of SNC as and emulsifier. Previously, the SNC underwent analytical analysis in order to understand and evaluate the isolated SNC. The ability of SNC as emulsifier was further investigated in this study. Emulsions with low, medium and high oil content has been prepared in function of different wt% of SNC. The emulsion stability against coalescence for two weeks has also been studied. Results showed that the emulsions prepared are steadily stable after one weeks of storage without any separation and changes. From the observation, there are two major factor contributed to the formation of emulsion and its stability, the SNC concentration and oil content. Relatively, higher percentage of SNC resulting a higher emulsion index, whereas no emulsion was formed if oil content exceeding 50% of the systems. The most suitable formulation to prepare Pickering Emulsion is the oil content around 45% and SNC concentration around 2 - 4%.

Characterization and emulsifying properties of β-lactoglobulin-gum Acacia Seyal conjugates prepared via the Maillard reaction.

PubMed

Bi, Binwei; Yang, Hao; Fang, Yapeng; Nishinari, Katsuyoshi; Phillips, Glyn O

2017-01-01

Gum Acacia Seyal (ASY) is less valued than is gum Acacia Senegal, due to its poor emulsifying ability. The present study investigated the Maillard reaction between ASY and β-lactoglobulin (BLG) and its impact on the emulsifying properties of ASY. The reaction products of BLG/ASY mixture (r=1/4), prepared by dry-heating at 60°C and a relative humidity of 79%, as a function of incubation time, were characterized by SDS-PAGE, GPC-MALLS and DSC. The results showed that 12-24h of dry-heating under the given conditions was sufficient for conjugation, meanwhile avoiding the formation of deeply coloured and insoluble melanoidins. More than 64% of the protein was incorporated into ASY, resulting in a two-fold increase in arabinogalactan-protein (AGP) content and 3.5 times increase in weight-average molecular mass of ASY. The conjugation with BLG markedly improved the stability of ASY-stabilized emulsions and their resistance against severe conditions, such as low pH and high saline conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spall behavior of cast iron with varying microstructures

NASA Astrophysics Data System (ADS)

Plume, Gifford; Rousseau, Carl-Ernst

2014-07-01

The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94-1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

Production of multicharged metal ion beams on the first stage of tandem-type ECRIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hagino, Shogo, E-mail: hagino@nf.eie.eng.osaka-u.ac.jp; Nagaya, Tomoki; Nishiokada, Takuya

2016-02-15

Multicharged metal ion beams are required to be applied in a wide range of fields. We aim at synthesizing iron-endohedral fullerene by transporting iron ion beams from the first stage into the fullerene plasma in the second stage of the tandem-type electron cyclotron resonance ion source (ECRIS). We developed new evaporators by using a direct ohmic heating method and a radiation heating method from solid state pure metal materials. We investigate their properties in the test chamber and produce iron ions on the first stage of the tandem-type ECRIS. As a result, we were successful in extracting Fe{sup +} ionmore » beams from the first stage and introducing Fe{sup +} ion beams to the second stage. We will try synthesizing iron-endohedral fullerene on the tandem-type ECRIS by using these evaporators.« less

THE INFLUENCE OF OXIDANT TYPE ON THE PROPERTIES OF IRON COLLOIDS AND SUSPENSIONS FORMED FROM FERROUS IRON

EPA Science Inventory

"Red water" describes the appearance of drinking water that contains suspended particulate iron although the actual suspension color may be light yellow to brown depending on water chemistry and particle properties. Iron can originate from the source water and from distribution ...

Selection of a discriminant and biorelevant in vitro dissolution test for the development of fenofibrate self-emulsifying lipid-based formulations.

PubMed

Pestieau, Aude; Krier, Fabrice; Brouwers, Adeline; Streel, Bruno; Evrard, Brigitte

2016-09-20

Fenofibrate, a BCS class II compound, has a low bioavailability especially when taken orally on an empty stomach. The challenge to find a new formulation for providing bioavailability, independent of food, is still ongoing. If the development of a suitable oral delivery formulation of BCS class II compounds is a frequent and great challenge to formulation scientists, the in vitro evaluation of these new formulations is also a great challenge. The purpose of this study was therefore to select an in vitro dissolution test that would be useful and as biorelevant as possible for the development of fenofibrate self-emulsifying lipid-based formulations. In this context, three different fenofibrate formulations, for which in vivo data are available in the literature, were tested using different dissolution tests until we found the one that was the most suitable. As part of this approach, we started with the simplest in vitro dissolution tests and progressed to tests that were increasingly more complex. The first tests were different single phase dissolution tests: a test under sink conditions based on the USP monograph, and different tests under non-sink conditions in non-biorelevant and biorelevant media. Given the inconclusive results obtained with these tests, biphasic dissolution systems were then tested: one with USP apparatus type II alone and another which combined USP apparatus types II and IV. This last combined test seemed the most suitable in vitro dissolution test for the development of the future fenofibrate lipid-based formulations we intend to develop in our own laboratory. Copyright © 2016 Elsevier B.V. All rights reserved.

Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine

PubMed Central

Calzas, Cynthia; Shiao, Tze Chieh; Neubauer, Axel; Kempker, Jennifer; Roy, René; Gottschalk, Marcelo

2016-01-01

Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections. PMID:27113360

Systems analysis of iron metabolism: the network of iron pools and fluxes

PubMed Central

2010-01-01

Background Every cell of the mammalian organism needs iron as trace element in numerous oxido-reductive processes as well as for transport and storage of oxygen. The very versatility of ionic iron makes it a toxic entity which can catalyze the production of radicals that damage vital membranous and macromolecular assemblies in the cell. The mammalian organism maintains therefore a complex regulatory network of iron uptake, excretion and intra-body distribution. Intracellular regulation in different cell types is intertwined with a global hormonal signalling structure. Iron deficiency as well as excess of iron are frequent and serious human disorders. They can affect every cell, but also the organism as a whole. Results Here, we present a kinematic model of the dynamic system of iron pools and fluxes. It is based on ferrokinetic data and chemical measurements in C57BL6 wild-type mice maintained on iron-deficient, iron-adequate, or iron-loaded diet. The tracer iron levels in major tissues and organs (16 compartment) were followed for 28 days. The evaluation resulted in a whole-body model of fractional clearance rates. The analysis permits calculation of absolute flux rates in the steady-state, of iron distribution into different organs, of tracer-accessible pool sizes and of residence times of iron in the different compartments in response to three states of iron-repletion induced by the dietary regime. Conclusions This mathematical model presents a comprehensive physiological picture of mice under three different diets with varying iron contents. The quantitative results reflect systemic properties of iron metabolism: dynamic closedness, hierarchy of time scales, switch-over response and dynamics of iron storage in parenchymal organs. Therefore, we could assess which parameters will change under dietary perturbations and study in quantitative terms when those changes take place. PMID:20704761

Topical nanoparticulate formulation of drugs for ocular keratitis

NASA Astrophysics Data System (ADS)

Yang, Xiaoyan

The primary objective of this project is to develop drug-loaded polymeric nanoparticles suspended in a biocompatible gel for topical delivery of therapeutic agents commonly employed in the treatment of ocular viral/bacterial keratitis. PART 1: Poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles (NP) of dipeptide monoester prodrugs of ganciclovir (GCV) including L-Val-L-Val-GCV (LLGCV), L-Val-D-Val-GCV (LDGCV), D-Val-L-Val-GCV (DLGCV) were formulated and dispersed in thermosensitive PLGA-PEG-PLGA polymer gel for the treatment of herpes simplex virus type 1 (HSV-1) induced viral corneal keratitis. NP containing prodrugs of GCV were prepared by a double-emulsion solvent evaporation technique using various PLGA polymers with different drug/polymer ratios. Cytotoxicity studies suggested that all NP formulations are non-toxic. In vitro release of prodrugs from NP showed a biphasic release pattern with an initial burst phase followed by a sustained phase. Such burst effect was completely eliminated when NP were suspended in thermosensitive gels with near zero-order release kinetics. Prodrugs-loaded PLGA NP dispersed in thermosensitive gels can thus serve as a promising drug delivery system for the treatment of anterior eye diseases. Maximum uptake (around 60%) was noted at 3 h for NP. Cellular uptake and intracellular accumulation of prodrugs are significantly different among three stereoisomeric dipeptide prodrugs. The microscopic images show that NP are avidly internalized by HCEC cells and distributed throughout the cytoplasm instead of being localized on the cell surface. Following cellular uptake, prodrugs released from NP gradually bioreversed into parent drug GCV. LLGCV showed the highest degradation rate, followed by LDGCV and DLGCV. LLGCV, LDGCV and DLGCV released from NP exhibited superior uptake and bioreversion in corneal cells. PART 2: PLGA NP of hydrocortisone butyrate (HB) suspended in thermosensitive PLGA-PEG-PLGA gel were developed for the treatment of bacterial corneal keratitis. Experimental designs were employed in order to investigate specific effects of independent variables during preparation of HB-loaded PLGA NP and corresponding responses in optimizing the formulation. NP containing HB were prepared by an oil-in-water (O/W) emulsion evaporation technique with different surfactants including polyvinyl alcohol (PVA), pluronic F-108 and chitosan. NP were characterized with respect to particle size, entrapment efficiency, polydispersity, drug loading, surface morphology, zeta potential and crystallinity. In vitro release of HB from NP showed a biphasic release pattern with an initial burst phase followed by a sustained phase. Such burst effect was completely eliminated when NP were suspended in thermosensitive gels and zero-order release kinetics was observed. Percentage of uptake in HCEC after 4 h was 59.09+/-6.21% for PVA-emulsified NP relative to 55.74+/-6.26% for pluronic-emulsified NP, and 62.54+/-3.30% for chitosan-emulsified NP, respectively. In HCEC cell line, chitosan-emulsified NP with chitosan showed highest cellular uptake efficiency over PVA- and pluronic-emulsified NP. However, NP with chitosan indicated significant cytotoxicity under 200 and 500 ?g/mL after 48 h, while NP with PVA and pluronic showed no significant cytotoxicity. PLGA NP dispersed in thermosensitive gels can be considered as a promising drug delivery system for the treatment of anterior eye diseases.

Development and investigation of a selective latex flocculant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikitin, I.N.; Preobrazhenskii, B.P.; Tsyrlov, M.Ya.

1982-01-01

Investigations were made on the use of two synthetic latexes as selective flocculants in the flotation cleaning of coal. The most commonly used latex in the industry contained sodium dibutylnaphthalenesulfonate, which is a biologically ''hard'' emulsifier. It was determined that butadiene-styrene latexes may successfully be used as selective coal sludge flocculants. The most efficient was a latex synthesized using biodegradable emulsifiers--potassium soaps of disproportionated rosin with a small quantity of synthetic fatty acids. Also, it was concluded that the values of the ash level in the flotation concentrate and tailings could be controlled by regulating the latex consumption.

Emulsifier-free emulsion polymerization produces highly charged, monodisperse particles for near infrared photonic crystals.

PubMed

Reese, Chad E; Asher, Sanford A

2002-04-01

We have developed emulsifier-free, emulsion polymerization recipes for the synthesis of highly charged, monodisperse latex particles of diameters between 500 and 1100 nm. These latexes consist of poly[styrene-(co-2-hydroxyethyl methacrylate)] spherical particles whose surfaces are functionalized with sulfate and carboxylic acid groups. These highly charged, monodisperse particles readily self-assemble into robust, three-dimensionally ordered crystalline colloidal array photonic crystals that Bragg diffract light in the near infrared spectral region. By altering the particle number density, the diffraction wavelength can be tuned from approximately 1000 to approximately 4000 nm.

Comparative study of the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours as affected by pH

PubMed Central

Raikos, Vassilios; Neacsu, Madalina; Russell, Wendy; Duthie, Garry

2014-01-01

The demand for products of high nutritional value from sustainable sources is growing rapidly in the global food market. In this study, the effect of pH on the functional properties of lupin, green pea, fava bean, hemp, and buckwheat flours was investigated and compared with wheat flour. Functional properties included solubility, emulsifying and foaming properties, gelling ability, and water holding capacity (WHC). All flours had minimal solubility at pH 4 and their corresponding values increased with increasing pH. Emulsifying properties were improved at pH 10 for all samples and emulsion stability showed a similar trend. Increasing pH in the range 4–10 enhanced the foaming properties of the flours, particularly buckwheat and hemp. Wheat, green pea, buckwheat, and fava bean were more capable of forming firm gels compared with lupin and hemp, as indicated by least gelling concentrations (LGCs). The ranking of the water binding properties of the different types of flours were lupin>hemp>fava bean>buckwheat>green pea>wheat. Results indicate that underutilized flours from sustainable plant sources could be exploited by the food industry as functional food ingredients or as replacements of wheat flour for various food applications. Depending on the application, flour functionality may be effectively tailored by pH adjustment. PMID:25493199

Gravity-directed separation of both immiscible and emulsified oil/water mixtures utilizing coconut shell layer.

PubMed

Li, Jian; Xu, Changcheng; Zhang, Yan; Tang, Xiaohua; Qi, Wei; Wang, Qiong

2018-02-01

Pressure-driven and lower flux of superwetting ultrafiltration membranes in various emulsions separation are long-standing issues and major barriers for their large-scale utilization. Even though currently reported membranes have achieved great success in emulsions separeation, they still suffer from low flux and complex fabrication process resulting from their smaller nanoscale pore size. Herein, utilizition of coconut shell as a novel biomaterial for developing into a layer through the simple smashing, cleaning and stacking procedures, which not only could avoid the complexity of film making process, but also could realize efficient gravity-directed separation of both immiscible oil/water mixtures and water-in-oil emulsions with high flux. Specifically, the layer acted as "water-removing" type filtrate material with excellent underwater superoleophobicity, exhibiting high efficiency for various immiscible oil/water mixtures separation and larger oil intrusion pressure. More importantly, the layer could also serve as adsorbent material with underoil superhydrophilicity, achieving gravity-directed kinds of water-in-oil emulsions separation with high separation efficiency (above 99.99%) and higher flux (above 1620L/m 2 h), even when their pore sizes are larger than that of emulsified droplets. We deeply believe that this study would open up a new strategy for both immiscible oil/water mixtures and water-in-oil emulsions separation. Copyright © 2017 Elsevier Inc. All rights reserved.

mRNA Regulation of Cardiac Iron Transporters and Ferritin Subunits in a Mouse Model of Iron Overload

PubMed Central

Brewer, Casey J.; Wood, Ruth I.; Wood, John C.

2014-01-01

Iron cardiomyopathy is the leading cause of death in iron overload. Men have twice the mortality rate of women, though the cause is unknown. In hemojuvelin-knockout mice, a model of the disease, males load more cardiac iron than females. We postulated that sex differences in cardiac iron import cause differences in cardiac iron concentration. RT-PCR was used to measure mRNA of cardiac iron transporters in hemojuvelin-knockout mice. No sex differences were discovered among putative importers of non-transferrin bound iron (L-type and T-type calcium channels, ZRT/IRT-like protein 14 zinc channels). Transferrin-bound iron transporters were also analyzed; these are controlled by the iron regulatory element/iron regulatory protein (IRE/IRP) system. There was a positive relationship between cardiac iron and ferroportin mRNA in both sexes, but it was significantly steeper in females (p<0.05). Transferrin receptor 1 and divalent metal transporter 1 were more highly expressed in females than males (p<0.01 and p<0.0001, respectively), consistent with their lower cardiac iron levels, as predicted by IRE/IRP regulatory pathways. Light-chain (L) ferritin showed a positive correlation with cardiac iron that was nearly identical in males and females (R2=0.41, p<0.01 and R2=0.56, p<0.05, respectively), while heavy-chain (H) ferritin was constitutively expressed in both sexes. This represents the first report of IRE/IRP regulatory pathways in the heart. Transcriptional regulation of ferroportin was suggested in both sexes, creating a potential mechanism for differential set points for iron export. Constitutive H-ferritin expression suggests a logical limit to cardiac iron buffering capacity at levels known to produce heart failure in humans. PMID:25220979

Process to Produce Iron Nanoparticle Lunar Dust Simulant Composite

NASA Technical Reports Server (NTRS)

Hung, Ching-cheh; McNatt, Jeremiah

2010-01-01

A document discusses a method for producing nanophase iron lunar dust composite simulant by heating a mixture of carbon black and current lunar simulant types (mixed oxide including iron oxide) at a high temperature to reduce ionic iron into elemental iron. The product is a chemically modified lunar simulant that can be attracted by a magnet, and has a surface layer with an iron concentration that is increased during the reaction. The iron was found to be -iron and Fe3O4 nanoparticles. The simulant produced with this method contains iron nanoparticles not available previously, and they are stable in ambient air. These nanoparticles can be mass-produced simply.

Disruption of the Hepcidin/Ferroportin Regulatory System Causes Pulmonary Iron Overload and Restrictive Lung Disease.

PubMed

Neves, Joana; Leitz, Dominik; Kraut, Simone; Brandenberger, Christina; Agrawal, Raman; Weissmann, Norbert; Mühlfeld, Christian; Mall, Marcus A; Altamura, Sandro; Muckenthaler, Martina U

2017-06-01

Emerging evidence suggests that pulmonary iron accumulation is implicated in a spectrum of chronic lung diseases. However, the mechanism(s) involved in pulmonary iron deposition and its role in the in vivo pathogenesis of lung diseases remains unknown. Here we show that a point mutation in the murine ferroportin gene, which causes hereditary hemochromatosis type 4 (Slc40a1 C326S ), increases iron levels in alveolar macrophages, epithelial cells lining the conducting airways and lung parenchyma, and in vascular smooth muscle cells. Pulmonary iron overload is associated with oxidative stress, restrictive lung disease with decreased total lung capacity and reduced blood oxygen saturation in homozygous Slc40a1 C326S/C326S mice compared to wild-type controls. These findings implicate iron in lung pathology, which is so far not considered a classical iron-related disorder. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Mechanisms of differentiation in the Skaergaard magma chamber

NASA Astrophysics Data System (ADS)

Tegner, C.; Lesher, C. E.; Holness, M. B.; Jakobsen, J. K.; Salmonsen, L. P.; Humphreys, M. C. S.; Thy, P.

2012-04-01

The Skaergaard intrusion is a superb natural laboratory for studying mechanisms of magma chamber differentiation. The magnificent exposures and new systematic sample sets of rocks that solidified inwards from the roof, walls and floor of the chamber provide means to test the relative roles of crystal settling, diffusion, convection, liquid immiscibility and compaction in different regions of the chamber and in opposite positions relative to gravity. Examination of the melt inclusions and interstitial pockets has demonstrated that a large portion of intrusion crystallized from an emulsified magma chamber composed of immiscible silica- and iron-rich melts. The similarity of ratios of elements with opposite partitioning between the immiscible melts (e.g. P and Rb) in wall, floor and roof rocks, however, indicate that large-scale separation did not occur. Yet, on a smaller scale of metres to hundred of metres and close to the interface between the roof and floor rocks (the Sandwich Horizon), irregular layers and pods of granophyre hosted by extremely iron-rich cumulates point to some separation of the two liquid phases. Similar proportions of the primocryst (cumulus) minerals in roof, wall and floor rocks indicate that crystal settling was not an important mechanism. Likewise, the lack of fractionation of elements with different behavior indicate that diffusion and fluid-driven metasomatism played relatively minor roles. Compositional convection and/or compaction within the solidifying crystal mush boundary layer are likely the most important mechanisms. A correlation of low trapped liquid fractions (calculated from strongly incompatible elements) in floor rocks with high fractionation density (the density difference between the crystal framework and the liquid) indicate that compaction is the dominating process in expelling evolved liquid from the crystal mush layer. This is supported by high and variable trapped liquid contents in the roof rocks, where gravity-driven compaction will not work.

Gold-Decorated Supraspheres of Block Copolymer Micelles

NASA Astrophysics Data System (ADS)

Kim, M. P.; Kang, D. J.; Kannon, A. G.; Jung, D.-W.; Yi, G. R.; Kim, B. J.

2012-02-01

Gold-decorated supraspheres displaying various surface morphologies were prepared by infiltration of gold precursor into polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) supraspheres under acidic condition. The supraspheres were fabricated by emulsifying PS-b-P2VP polymer solution into surfactant solution. Selective swelling of P2VP in the suprasphere by gold precursor under acidic condition resulted in the formation of gold-decorated supraspheres with various surface structures. As evidenced by TEM and SEM images, dot pattern was formed in the case of smaller supraspheres than 800 nm; whereas fingerprint-like pattern was observed in larger supraspheres than 800 nm. Gold nanoparticles were located inside P2VP domains near the surface of prepared supraspheres as confirmed by TEM. The optical property of the supraspheres was characterized using UV-vis absorption spectroscopy and the maximum absorption peak at around 580 nm was observed, which means that gold nanoparticles densely packed into P2VP domain on the suprasphere. Our approach to prepare gold-decorated supraspheres can be extended to other metallic particles such as iron oxide or platinum nanoparticles, and those precursors can be also selectively incorporated into the P2VP domain.

The role of endocytic pathways in cellular uptake of plasma non-transferrin iron

PubMed Central

Sohn, Yang-Sung; Ghoti, Hussam; Breuer, William; Rachmilewitz, Eliezer; Attar, Samah; Weiss, Guenter; Cabantchik, Z. Ioav

2012-01-01

Background In transfusional siderosis, the iron binding capacity of plasma transferrin is often surpassed, with concomitant generation of non-transferrin-bound iron. Although implicated in tissue siderosis, non-transferrin-bound iron modes of cell ingress remain undefined, largely because of its variable composition and association with macromolecules. Using fluorescent tracing of labile iron in endosomal vesicles and cytosol, we examined the hypothesis that non-transferrin-bound iron fractions detected in iron overloaded patients enter cells via bulk endocytosis. Design and Methods Fluorescence microscopy and flow cytometry served as analytical tools for tracing non-transferrin-bound iron entry into endosomes with the redox-reactive macromolecular probe Oxyburst-Green and into the cytosol with cell-laden calcein green and calcein blue. Non-transferrin-bound iron-containing media were from sera of polytransfused thalassemia major patients and model iron substances detected in thalassemia major sera; cell models were cultured macrophages, and cardiac myoblasts and myocytes. Results Exposure of cells to ferric citrate together with albumin, or to non-transferrin-bound iron-containing sera from thalassemia major patients caused an increase in labile iron content of endosomes and cytosol in macrophages and cardiac cells. This increase was more striking in macrophages, but in both cell types was largely reduced by co-exposure to non-transferrin-bound iron-containing media with non-penetrating iron chelators or apo-transferrin, or by treatment with inhibitors of endocytosis. Endosomal iron accumulation traced with calcein-green was proportional to input non-transferrin-bound iron levels (r2=0.61) and also preventable by pre-chelation. Conclusions Our studies indicate that macromolecule-associated non-transferrin-bound iron can initially gain access into various cells via endocytic pathways, followed by iron translocation to the cytosol. Endocytic uptake of plasma non-transferrin-bound iron is a possible mechanism that can contribute to iron loading of cell types engaged in bulk/adsorptive endocytosis, highlighting the importance of its prevention by iron chelation. PMID:22180428

Designing non-native iron-binding site on a protein cage for biological synthesis of nanoparticles.

PubMed

Peng, Tao; Paramelle, David; Sana, Barindra; Lee, Chiu Fan; Lim, Sierin

2014-08-13

In biomineralization processes, a supramolecular organic structure is often used as a template for inorganic nanomaterial synthesis. The E2 protein cage derived from Geobacillus stearothermophilus pyruvate dehydrogenase and formed by the self-assembly of 60 subunits, has been functionalized with non-native iron-mineralization capability by incorporating two types of iron-binding peptides. The non-native peptides introduced at the interior surface do not affect the self-assembly of E2 protein subunits. In contrast to the wild-type, the engineered E2 protein cages can serve as size- and shape-constrained reactors for the synthesis of iron nanoparticles. Electrostatic interactions between anionic amino acids and cationic iron molecules drive the formation of iron oxide nanoparticles within the engineered E2 protein cages. The work expands the investigations on nanomaterial biosynthesis using engineered host-guest encapsulation properties of protein cages. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of different iron compounds on wheat and gluten-free breads.

PubMed

Kiskini, Alexandra; Kapsokefalou, Maria; Yanniotis, Stavros; Mandala, Ioanna

2010-05-01

Iron fortification of bread often results in sub-optimal quality of the final product due to undesirable changes in the physical characteristics and sensory properties of the bread. In this study both the form of iron (soluble, insoluble or encapsulated) and the type of bread (wheat or gluten-free) were varied in order to investigate the effect of iron and gluten on the product characteristics. The effect of iron on the quality characteristics of the breads investigated depended on iron type, but not on iron solubility. Colour, crust firmness, specific volume, cell number and uniformity as well as aroma were the attributes that were mainly affected in iron-enriched wheat bread. In some cases, specific volume was 30% lower than that of the control sample, while cell uniformity was significantly lower, as low as 50% of the control sample in some fortified samples. In gluten-free breads, differences between unfortified and fortified samples included colour, crust firmness, cell number, 'moisture' odour, metallic taste and stickiness. In some cases, the sensory scores were better for fortified samples. Differences due to iron fortification were less pronounced in gluten-free compared to wheat breads. The choice of the appropriate iron compound which will not cause adverse quality changes is still a challenge.

Dietary emulsifiers from milk and soybean differently impact adiposity and inflammation in association with modulation of colonic goblet cells in high-fat fed mice.

PubMed

Lecomte, Manon; Couëdelo, Leslie; Meugnier, Emmanuelle; Plaisancié, Pascale; Létisse, Marion; Benoit, Bérengère; Gabert, Laure; Penhoat, Armelle; Durand, Annie; Pineau, Gaëlle; Joffre, Florent; Géloën, Alain; Vaysse, Carole; Laugerette, Fabienne; Michalski, Marie-Caroline

2016-03-01

Enhanced adiposity and metabolic inflammation are major features of obesity that could be impacted by dietary emulsifiers. We investigated in high-fat fed mice the effects of using a new polar lipid (PL) emulsifier from milk (MPL) instead of soybean lecithin (soybean PL [SPL]) on adipose tissue and intestinal mucosa function. Four groups of C57BL6 mice received for 8 wks a low-fat (LF) diet or a high-fat diet devoid of PLs or an high-fat diet including MPL (high-fat-MPL) or SPL (high-fat-SPL). Compared with high-fat diet, high-fat-SPL diet increased white adipose tissue (WAT) mass (p < 0.05), with larger adipocytes (p < 0.05) and increased expression of tumor necrosis factor alpha, monochemoattractant protein-1, LPS-binding protein, and leptin (p < 0.05). This was not observed with high-fat-MPL diet despite similar dietary intakes and increased expression of fatty acid transport protein 4 and microsomal TG transfer protein, involved in lipid absorption, in upper intestine (p < 0.05). High-fat-MPL mice had a lower expression in WAT of cluster of differentiation 68, marker of macrophage infiltration, versus high-fat and high-fat-SPL mice (p < 0.05), and more goblet cells in the colon (p < 0.05). Unlike SPL, MPL in the high-fat diet did not induce WAT hypertrophy and inflammation but increased colonic goblet cells. This supports further clinical exploration of different sources of dietary emulsifiers in the frame of obesity outbreak. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Proximal chemical composition and functional properties of fresh meat of crab claws (Homalaspis plana)].

PubMed

Abugoch, L; Barrios, J; Guarda, A

1996-12-01

The research of alternative technological processes is being necessary in order to obtain a better utilization of hydrobiologic resources and food products, with higher added value. Crab (Homolaspis plana) is a crustacean found along the Chilean coast, whose flesh is exported as a frozen product. The resource crab is scantly studied in Chile and could became an excellent raw material for "delicatessen" products, with a high market value. The proximal composition, through the protein, fat, moisture and ashes content was determined. The non nitrogen extract was calculated by difference. The functional properties (water retention, emulsifying and gel-forming capacities) of fresh crab claws meat without additives were measured. The proximal composition for the claw meat was: 79,34 +/- 1.12% moisture, 16.75 +/- 1.29% protein, 1.86 +/- 0.11% ashes, 0.11 +/- 0.01 fat % and 1.93 +/- 1.07% N.N.E. In relation with the emulsifying capacity, claw meat was able to emulsify 2,259.03 +/- 73.04 g vegetal oil/g protein. The water retention was 154.49 +/- 6.85% representing the increase in mass percent; and the force of the gel formed in claw meat was 195.3 +/- 17.16 g-force x cm. According to these results, the claw crab is an attractive food, with a high protein and low fat content. Crab meat showed an excellent emulsifying capacity and water retention, so it can be used as a good raw material for the development of smearing products. In the case of gel-like products, further studies will be required, in order to optimize the conditions in which a stronger gel could be obtained.

The use of Papuan iron sand and river sand for fine aggregate in mortar for nuclear radiation shield application

NASA Astrophysics Data System (ADS)

Dahlan, K.; Haryati, E.; Aninam, Y. S.

2018-03-01

This study explores the effect of fine aggregate on mortar properties and its application as a nuclear shield. This study was based on a hypothesis that the types of aggregate applied as radiation shield determined the level of its effectiveness on preventing nuclear radiation. There are two types and sources of fine aggregate that was used as main ingredients for mortar production in this research, namely iron sand and river sand. Both types of sand were derived from the respective regions of Sarmi and Jayapura, Papua. The results showed that the mortar materials that were produced with the iron sand provided better results in dispelling radiation than that of river sand. The compressive strength of fine aggregate from the iron sand was 21.62 MPa, while the compressive strength of the river sand was 16.8 MPa. Measuring the attenuation coefficient of material, we found that the largest aggregated value of mortar with fine iron sand reached 0.0863 / cm. On the other hand, the smallest HVT (Half Value Thickness) was obtained from the iron sand mortar, at 8.03 cm.

The occurrence and origin of lamellar troilite in iron meteorites

USGS Publications Warehouse

Brett, R.; Henderson, E.P.

1967-01-01

A number of iron meteorites contain elongated inclusions consisting predominantly of troilite, which have been termed Reichenbach lamellae. Two types of inclusions exist, the first up to 6 cm long and 0??2 mm wide, the second up to 2 cm long and 3 mm wide. The first type contains troilite with subordinate daubreelite and is commonly rimmed by schreibersite and swathing kamacite; the second consists largely of troilite with daubreelite and rare graphite and silicate grains. Both types formed from a residual sulfide melt after the solidification of Ni{single bond}Fe metal. Swatching kamacite surrounding troilite in iron meteorites formed by nucleation at the troilite-metal interface during the formation of the Widmansta??tten texture. Meteorites containing troilite inclusions of the second type appear to have cooled more rapidly than most iron meteorites. In view of the confusion surrounding the use of the term Reichenbach lamella, it is suggested that the term be dropped from the literature. ?? 1967.

Adelphi-Goddard emulsified fuel project. [using water/oil emulsions

NASA Technical Reports Server (NTRS)

1977-01-01

Thermal efficiency and particle emissions were studied using water/oil emulsions. These studies were done using number 2 and number 6 fuel oil. The number 6 oil had a sulfur content greater than one percent and experiments were conducted to remove the sulfur dioxide from the stack gases. Test findings include: (1) emulsion effected a reduction in soot at a low excess air levels; (2) a steam atomizing system will produce a water/oil emulsion. The fuel in the study was emulsified in the steam atomization process, hence, pre-emulsification did not yield a dramatic reduction in soot or an increase in thermal efficiency.

Synthesis and characterization of fluorinated polyacrylate latex emulsified with novel surfactants.

PubMed

Zhang, Cuifeng; Xu, Tingting; Bao, Zhongbin; Chen, Lijun

2017-01-01

The fluorinated polyacrylate latex were successfully prepared with semi- continuous seeded emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and hexafluorobutyl methacrylate (HFMA) which was initiated with potassium persulfate (KPS) initiator and emulsified with the novel mixed surfactants of sodium lauryl glutamate (SLG) and alkylphenol ethoxylates (OP-10). The structure of the resultant latex was confirmed by Fourier transform infrared spectroscopy (FTIR). The particle size of the latex was measured by Zetatrac dynamic light scattering detector. The film of latex was tested by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and contact angle (CA). The optimum conditions of preparing the novel fluorinated polyacrylate latex are optimized and the results are as follows: the amount of emulsifiers is 4.0%; mass ratio of SLG to OP-10 is 1:1, the amount of the initiator is 0.6%. The mass ratio of MMA to BA is 1:1 and the amount of HFMA is 7.0%. In this case, the conversion is high and the polymerization stability is good. In addition, the water resistance and thermal properties of the latex films were improved significantly in comparison with the film of the latex prepared without the fluorinated monomer.

Synthesis and characterization of fluorinated polyacrylate latex emulsified with novel surfactants

PubMed Central

Zhang, Cuifeng; Xu, Tingting; Bao, Zhongbin; Chen, Lijun

2017-01-01

Abstract The fluorinated polyacrylate latex were successfully prepared with semi- continuous seeded emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and hexafluorobutyl methacrylate (HFMA) which was initiated with potassium persulfate (KPS) initiator and emulsified with the novel mixed surfactants of sodium lauryl glutamate (SLG) and alkylphenol ethoxylates (OP-10). The structure of the resultant latex was confirmed by Fourier transform infrared spectroscopy (FTIR). The particle size of the latex was measured by Zetatrac dynamic light scattering detector. The film of latex was tested by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and contact angle (CA). The optimum conditions of preparing the novel fluorinated polyacrylate latex are optimized and the results are as follows: the amount of emulsifiers is 4.0%; mass ratio of SLG to OP-10 is 1:1, the amount of the initiator is 0.6%. The mass ratio of MMA to BA is 1:1 and the amount of HFMA is 7.0%. In this case, the conversion is high and the polymerization stability is good. In addition, the water resistance and thermal properties of the latex films were improved significantly in comparison with the film of the latex prepared without the fluorinated monomer. PMID:29491785

Effect of emulsion size and shelf life of azadirachtin A on the bioefficacy of neem (Azadirachta indica A. Juss) emulsifiable concentrates.

PubMed

Kumar, L; Parmar, B S

2000-08-01

In a study of 33 recipes of neem oil based emulsifiable concentrates, the specific surface area of the emulsions and cream plus oil layer separation in emulsions at 24 h revealed a correlation of -0.6874 between them and correlations of -0.8940 and 0.6972, respectively, with bioefficacy (LC(50)) against the 3-day-old second-instar larvae of the Bihar hairy caterpillar, Spilosoma obliqua Walker. Nearly 96-99% of azadirachtin A in emulsifiable concentrates (aza-A content = 617.93-1149.65 ppm) degraded during the heat stability test at 54 +/- 1 degrees C for 14 days with half-lives ranging between 1.84 and 4.53 days. The LC(50) values against S. obliqua were, however, statistically at par in both the pre- and the post-heat-treated samples, suggesting a similar effect of azadirachtin A and its degradation products on the bioactivity. The half-life of azadirachtin A could be enhanced by storing the concentrates at lower temperatures. A low pH of the formulation solvent did not check the degradation of azadirachtin A, as reported with aqueous solutions in the literature.

A facile method for emulsified oil-water separation by using polyethylenimine-coated magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Lü, Ting; Qi, Dongming; Zhang, Dong; Lü, Yulan; Zhao, Hongting

2018-04-01

Oil spills and oily wastewater discharges from ships and industrial activities have serious impacts on the environment and human health. In this study, a class of easy-to-synthesize polyethylenimine (PEI)-coated Fe3O4 magnetic nanoparticles (MNPs) was successfully synthesized via a one-step coprecipitation method. The synthesized PEI-coated Fe3O4 MNPs were characterized by using multiple technologies and applied in emulsified oil-water separation for the first time. It was found that the PEI effectively tuned the surface charge and wettability of MNPs. As a result, the PEI-coated MNPs could successfully assemble at the oil-water interface and promote the coalescence of oil droplets, thereby facilitating the subsequent magnetic separation. Results showed that the oil-water separation performance was superior and enhanced with the increase of ionic strength. Recycling experiment indicated that the PEI-coated MNPs could be reused up to six times without showing a significant decrease in separation efficiency. All of these results suggested that the PEI-coated MNP could potentially be used as a class of promising nanomaterials for emulsified oil-water separation. [Figure not available: see fulltext.

Emulsifying Properties of Oxidatively Stressed Myofibrillar Protein Emulsion Gels Prepared with (-)-Epigallocatechin-3-gallate and NaCl.

PubMed

Feng, Xianchao; Chen, Lin; Lei, Na; Wang, Shuangxi; Xu, Xinglian; Zhou, Guanghong; Li, Zhixi

2017-04-05

The dose-dependent effects of (-)-epigallocatechin-3-gallate (EGCG; 0, 100, or 1000 ppm) on the textural properties and stability of a myofibrillar protein (MP) emulsion gel were investigated. Addition of EGCG significantly inhibited formation of carbonyl but promoted the loss of both thiol and free amine groups. Addition of EGCG, particularly at 1000 ppm, initiated irreversible protein modifications, as evidenced by surface hydrophobicity changes, patterns in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and differential scanning calorimetry. These results indicated that MP was modified by additive reactions between the quinone of EGCG and thiols and free amines of proteins. These adducts increased cooking loss and destabilized the texture, especially with a large EGCG dose. Confocal laser scanning microscopy and scanning electron microscopy images clearly indicated the damage to the emulsifying properties and the collapse of the internal structure when the MP emulsion gel was treated with a large EGCG dose. A high concentration of NaCl (0.6 M) improved modification of MP and increased the rate of deterioration of the internal structure, especially with the large EGCG dose (1000 ppm), resulting in an MP emulsion gel with extremely unstable emulsifying properties.

Disorders associated with systemic or local iron overload: from pathophysiology to clinical practice.

PubMed

Sebastiani, Giada; Pantopoulos, Kostas

2011-10-01

In healthy subjects, the rate of dietary iron absorption, as well as the amount and distribution of body iron are tightly controlled by hepcidin, the iron regulatory hormone. Disruption of systemic iron homeostasis leads to pathological conditions, ranging from anemias caused by iron deficiency or defective iron traffic, to iron overload (hemochromatosis). Other iron-related disorders are caused by misregulation of cellular iron metabolism, which results in local accumulation of the metal in mitochondria. Brain iron overload is observed in neurodegenerative disorders. Secondary hemochromatosis develops as a complication of another disease. For example, repeated blood transfusions, a standard treatment of various anemias characterized by ineffective erythropoiesis, promote transfusional siderosis, while chronic liver diseases are often associated with mild to moderate secondary iron overload. In this critical review, we discuss pathophysiological and clinical aspects of all types of iron metabolism disorders (265 references). This journal is © The Royal Society of Chemistry 2011

The Iron Metallome in Eukaryotic Organisms

PubMed Central

Dlouhy, Adrienne C.; Outten, Caryn E.

2013-01-01

This chapter is focused on the iron metallome in eukaryotes at the cellular and subcellular level, including properties, utilization in metalloproteins, trafficking, storage, and regulation of these processes. Studies in the model eukaryote Saccharomyces cerevisiae and mammalian cells will be highlighted. The discussion of iron properties will center on the speciation and localization of intracellular iron as well as the cellular and molecular mechanisms for coping with both low iron bioavailability and iron toxicity. The section on iron metalloproteins will emphasize heme, iron-sulfur cluster, and non-heme iron centers, particularly their cellular roles and mechanisms of assembly. The section on iron uptake, trafficking, and storage will compare methods used by yeast and mammalian cells to import iron, how this iron is brought into various organelles, and types of iron storage proteins. Regulation of these processes will be compared between yeast and mammalian cells at the transcriptional, post-transcriptional, and post-translational levels. PMID:23595675

Co-precipitation of phosphate and iron limits mitochondrial phosphate availability in Saccharomyces cerevisiae lacking the yeast frataxin homologue (YFH1).

PubMed

Seguin, Alexandra; Santos, Renata; Pain, Debkumar; Dancis, Andrew; Camadro, Jean-Michel; Lesuisse, Emmanuel

2011-02-25

Saccharomyces cerevisiae cells lacking the yeast frataxin homologue (Δyfh1) accumulate iron in the mitochondria in the form of nanoparticles of ferric phosphate. The phosphate content of Δyfh1 mitochondria was higher than that of wild-type mitochondria, but the proportion of mitochondrial phosphate that was soluble was much lower in Δyfh1 cells. The rates of phosphate and iron uptake in vitro by isolated mitochondria were higher for Δyfh1 than wild-type mitochondria, and a significant proportion of the phosphate and iron rapidly became insoluble in the mitochondrial matrix, suggesting co-precipitation of these species after oxidation of iron by oxygen. Increasing the amount of phosphate in the medium decreased the amount of iron accumulated by Δyfh1 cells and improved their growth in an iron-dependent manner, and this effect was mostly transcriptional. Overexpressing the major mitochondrial phosphate carrier, MIR1, slightly increased the concentration of soluble mitochondrial phosphate and significantly improved various mitochondrial functions (cytochromes, [Fe-S] clusters, and respiration) in Δyfh1 cells. We conclude that in Δyfh1 cells, soluble phosphate is limiting, due to its co-precipitation with iron.

Effect of partial replacement of pork meat with an olive oil organogel on the physicochemical and sensory quality of dry-ripened venison sausages.

PubMed

Utrilla, M C; García Ruiz, A; Soriano, A

2014-08-01

A venison salchichon was made using varying proportions of olive oil to replace the traditional pork meat and to obtain a healthier product. Six types of salchichon were produced. The control type contained 75% lean venison and 25% pork meat; in the other types, 15%, 25%, 35%, 45% and 55% of the pork meat were replaced by olive oil introduced in the form of an organogel (olive oil emulsified with soy protein and water). All types were satisfactory in terms of physicochemical characteristics (pH, a(w), moisture loss) and instrumental colour throughout ripening, and displayed acceptable levels of lipolysis (acidity index) and lipid oxidation (TBARS). Higher proportions of olive oil prompted an increase in monounsaturated fatty acid content (mainly C18:1). All six types of salchichon were judged acceptable by consumers, the highest scores being given to those in which no more than 25% of the pork meat was replaced by olive oil. Copyright © 2014 Elsevier Ltd. All rights reserved.

Prion protein modulates glucose homeostasis by altering intracellular iron.

PubMed

Ashok, Ajay; Singh, Neena

2018-04-26

The prion protein (PrP C ), a mainly neuronal protein, is known to modulate glucose homeostasis in mouse models. We explored the underlying mechanism in mouse models and the human pancreatic β-cell line 1.1B4. We report expression of PrP C on mouse pancreatic β-cells, where it promoted uptake of iron through divalent-metal-transporters. Accordingly, pancreatic iron stores in PrP knockout mice (PrP -/- ) were significantly lower than wild type (PrP +/+ ) controls. Silencing of PrP C in 1.1B4 cells resulted in significant depletion of intracellular (IC) iron, and remarkably, upregulation of glucose transporter GLUT2 and insulin. Iron overloading, on the other hand, resulted in downregulation of GLUT2 and insulin in a PrP C -dependent manner. Similar observations were noted in the brain, liver, and neuroretina of iron overloaded PrP +/+ but not PrP -/- mice, indicating PrP C -mediated modulation of insulin and glucose homeostasis through iron. Peripheral challenge with glucose and insulin revealed blunting of the response in iron-overloaded PrP +/+ relative to PrP -/- mice, suggesting that PrP C -mediated modulation of IC iron influences both secretion and sensitivity of peripheral organs to insulin. These observations have implications for Alzheimer's disease and diabetic retinopathy, known complications of type-2-diabetes associated with brain and ocular iron-dyshomeostasis.

Iron loading in HFE p.C282Y homozygotes found by population screening: relationships to HLA-type and T-lymphocyte subsets.

PubMed

Thorstensen, Ketil; Kvitland, Mona A; Irgens, Wenche Ø; Åsberg, Arne; Borch-Iohnsen, Berit; Moen, Torolf; Hveem, Kristian

2017-11-01

Iron loading in p.C282Y homozygous HFE hemochromatosis subjects is highly variable, and it is unclear what factors cause this variability. Finding such factors could aid in predicting which patients are at highest risk and require closest follow-up. The degree of iron loading has previously been associated with certain HLA-types and with abnormally low CD8 + cell counts in peripheral blood. In 183 Norwegian, p.C282Y homozygotes (104 men, 79 women) originally found through population screening we determined HLA type and measured total T-lymphocytes, CD4 + and CD8 + cells, and compared this with data on iron loading. In p.C282Y homozygous men, but not in homozygous women, we found that the presence of two HLA-A*03 alleles increased the iron load on average by approximately 2-fold compared to p.C282Y homozygous men carrying zero or one A*03 allele. On the other hand, the presence of two HLA-A*01 alleles, in male subjects, apparently reduced the iron loading. In p.C282Y homozygous individuals, the iron loading was increased if the CD8 + cell number was below the 25 percentile or if the CD4 + cell number was above the 75 percentile. This effect appeared to be additive to the effect of the number of HLA-A*03 alleles. Our data indicate that homozygosity for the HLA-A*03 allele significantly increases the risk of excessive iron loading in Norwegian p.C282Y homozygous male patients. In addition, low CD8 + cell number or high CD4 + cell number further increases the risk of excessive iron loading.

Interaction of some extreme-pressure type lubricating compounds with an iron surface

NASA Technical Reports Server (NTRS)

Buckley, D. H.

1973-01-01

An iron surface was exposed to the extreme-pressure type lubricant benzyl chloride, dichlorophenyl phosphine, dichlorophenyl phosphine sulfide, ophenyl phosphine oxide. Iron, in the sputter-cleaned state, was exposed to these materials statically and during dynamic friction experiments. With benzyl chloride only chlorine adsorbed to the surface, and with dichlorophenyl phosphine no adsorption occurred, while the addition of sulfur to that same molecular structure resulted in the promotion of carbon and chlorine adsorption. substitution of oxygen for sulfur in the dichlorobenzyl phosphine molecule resulted in carbon, chlorine, and oxygen adsorption. With none of the phosphorus containing molecules was phosphorus detected on the surface. Sliding in an atmosphere of benzyl chloride promoted adsorption of chlorine to the iron surface. Increases in load resulted in a decrease in the surface concentration of iron chloride.

It's no laughing matter: An exploratory study of the use of ironic versus sarcastic humor in health-related advertising messages.

PubMed

Iles, Irina Alexandra; Nan, Xiaoli

2017-01-01

We examined the persuasive effects of ironic and sarcastic versus no humor appeals in health messages and the potential differential effects of ironic versus sarcastic humor. Findings of a controlled experiment (N = 303) suggested that sarcastic messages, as compared to no humor messages, resulted in less negative affect, more counterarguing, and decreased perceived argument strength. Ironic messages led to more counterarguing than no humor messages. Significant differences in counterarguing, perceived argument strength, and attitudes toward the risky behavior were detected between the two humor types. Counterarguing mediated the indirect effect of message type on attitudes toward the risky behavior.

Iron Overload and Apoptosis of HL-1 Cardiomyocytes: Effects of Calcium Channel Blockade

PubMed Central

Chen, Mei-pian; Cabantchik, Z. Ioav; Chan, Shing; Chan, Godfrey Chi-fung; Cheung, Yiu-fai

2014-01-01

Background Iron overload cardiomyopathy that prevails in some forms of hemosiderosis is caused by excessive deposition of iron into the heart tissue and ensuing damage caused by a raise in labile cell iron. The underlying mechanisms of iron uptake into cardiomyocytes in iron overload condition are still under investigation. Both L-type calcium channels (LTCC) and T-type calcium channels (TTCC) have been proposed to be the main portals of non-transferrinic iron into heart cells, but controversies remain. Here, we investigated the roles of LTCC and TTCC as mediators of cardiac iron overload and cellular damage by using specific Calcium channel blockers as potential suppressors of labile Fe(II) and Fe(III) ingress in cultured cardiomyocytes and ensuing apoptosis. Methods Fe(II) and Fe(III) uptake was assessed by exposing HL-1 cardiomyocytes to iron sources and quantitative real-time fluorescence imaging of cytosolic labile iron with the fluorescent iron sensor calcein while iron-induced apoptosis was quantitatively measured by flow cytometry analysis with Annexin V. The role of calcium channels as routes of iron uptake was assessed by cell pretreatment with specific blockers of LTCC and TTCC. Results Iron entered HL-1 cardiomyocytes in a time- and dose-dependent manner and induced cardiac apoptosis via mitochondria-mediated caspase-3 dependent pathways. Blockade of LTCC but not of TTCC demonstrably inhibited the uptake of ferric but not of ferrous iron. However, neither channel blocker conferred cardiomyocytes with protection from iron-induced apoptosis. Conclusion Our study implicates LTCC as major mediators of Fe(III) uptake into cardiomyocytes exposed to ferric salts but not necessarily as contributors to ensuing apoptosis. Thus, to the extent that apoptosis can be considered a biological indicator of damage, the etiopathology of cardiosiderotic damage that accompanies some forms of hemosiderosis would seem to be unrelated to LTCC or TTCC, but rather to other routes of iron ingress present in heart cells. PMID:25390893

Retention of iron by infants.

PubMed

Fomon, S J; Nelson, S E; Ziegler, E E

2000-01-01

Throughout the world, the most common nutritional deficiency disorder of infants is iron deficiency. Developing effective strategies for preventing iron deficiency requires detailed knowledge of iron retention under ordinary living conditions. For the adult population, such knowledge is at an advanced stage, but relatively little is known about infants. Many reports of iron retention by infants have been based on the assumption that, as in normal and iron-deficient adults, 80%-100% of newly absorbed iron is promptly incorporated into circulating erythrocytes, but this assumption is not supported by available data. This communication presents a review of iron retention by term and preterm infants, as determined by metabolic balance studies or (59)Fe whole-body counting studies, and it explores the relationship between iron retention and postnatal age, iron nutritional status, iron intake (or dose), and type of feeding.

Iron, ferritin, and nutrition.

PubMed

Theil, Elizabeth C

2004-01-01

Ferritin, a major form of endogenous iron in food legumes such as soybeans, is a novel and natural alternative for iron supplementation strategies where effectiveness is limited by acceptability, cost, or undesirable side effects. A member of the nonheme iron group of dietary iron sources, ferritin is a complex with Fe3+ iron in a mineral (thousands of iron atoms inside a protein cage) protected from complexation. Ferritin illustrates the wide range of chemical and biological properties among nonheme iron sources. The wide range of nonheme iron receptors matched to the structure of the iron complexes that occurs in microorganisms may, by analogy, exist in humans. An understanding of the chemistry and biology of each type of dietary iron source (ferritin, heme, Fe2+ ion, etc.), and of the interactions dependent on food sources, genes, and gender, is required to design diets that will eradicate global iron deficiency in the twenty-first century.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baraibar, Martin A.; Muhoberac, Barry B.; Garringer, Holly J.

Mutations in the coding sequence of the ferritin light chain (FTL) gene cause a neurodegenerative disease known as neuroferritinopathy or hereditary ferritinopathy, which is characterized by the presence of intracellular inclusion bodies containing the mutant FTL polypeptide and by abnormal accumulation of iron in the brain. Here, we describe the x-ray crystallographic structure and report functional studies of ferritin homopolymers formed from the mutant FTL polypeptide p.Phe167SerfsX26, which has a C terminus that is altered in amino acid sequence and length. The structure was determined and refined to 2.85 {angstrom} resolution and was very similar to the wild type betweenmore » residues Ile-5 and Arg-154. However, instead of the E-helices normally present in wild type ferritin, the C-terminal sequences of all 24 mutant subunits showed substantial amounts of disorder, leading to multiple C-terminal polypeptide conformations and a large disruption of the normally tiny 4-fold axis pores. Functional studies underscored the importance of the mutant C-terminal sequence in iron-induced precipitation and revealed iron mishandling by soluble mutant FTL homopolymers in that only wild type incorporated iron when in direct competition in solution with mutant ferritin. Even without competition, the amount of iron incorporation over the first few minutes differed severalfold. Our data suggest that disruption at the 4-fold pores may lead to direct iron mishandling through attenuated iron incorporation by the soluble form of mutant ferritin and that the disordered C-terminal polypeptides may play a major role in iron-induced precipitation and formation of ferritin inclusion bodies in hereditary ferritinopathy.« less

Effects of exogenous pyoverdines on Fe availability and their impacts on Mn(II) oxidation by Pseudomonas putida GB-1

PubMed Central

Lee, Sung-Woo; Parker, Dorothy L.; Geszvain, Kati; Tebo, Bradley M.

2014-01-01

Pseudomonas putida GB-1 is a Mn(II)-oxidizing bacterium that produces pyoverdine-type siderophores (PVDs), which facilitate the uptake of Fe(III) but also influence MnO2 formation. Recently, a non-ribosomal peptide synthetase mutant that does not synthesize PVD was described. Here we identified a gene encoding the PVDGB-1 (PVD produced by strain GB-1) uptake receptor (PputGB1_4082) of strain GB-1 and confirmed its function by in-frame mutagenesis. Growth and other physiological responses of these two mutants and of wild type were compared during cultivation in the presence of three chemically distinct sets of PVDs (siderotypes n°1, n°2, and n°4) derived from various pseudomonads. Under iron-limiting conditions, Fe(III) complexes of various siderotype n°1 PVDs (including PVDGB-1) allowed growth of wild type and the synthetase mutant, but not the receptor mutant, confirming that iron uptake with any tested siderotype n°1 PVD depended on PputGB1_4082. Fe(III) complexes of a siderotype n°2 PVD were not utilized by any strain and strongly induced PVD synthesis. In contrast, Fe(III) complexes of siderotype n°4 PVDs promoted the growth of all three strains and did not induce PVD synthesis by the wild type, implying these complexes were utilized for iron uptake independent of PputGB1_4082. These differing properties of the three PVD types provided a way to differentiate between effects on MnO2 formation that resulted from iron limitation and others that required participation of the PVDGB-1 receptor. Specifically, MnO2 production was inhibited by siderotype n°1 but not n°4 PVDs indicating PVD synthesis or PputGB1_4082 involvement rather than iron-limitation caused the inhibition. In contrast, iron limitation was sufficient to explain the inhibition of Mn(II) oxidation by siderotype n°2 PVDs. Collectively, our results provide insight into how competition for iron via siderophores influences growth, iron nutrition and MnO2 formation in more complex environmental systems. PMID:25009534

Metabolic crossroads of iron and copper

PubMed Central

Collins, James F; Prohaska, Joseph R; Knutson, Mitchell D

2013-01-01

Interactions between the essential dietary metals, iron and copper, have been known for many years. This review highlights recent advances in iron-copper interactions with a focus on tissues and cell types important for regulating whole-body iron and copper homeostasis. Cells that mediate dietary assimilation (enterocytes) and storage and distribution (hepatocytes) of iron and copper are considered, along with the principal users (erythroid cells) and recyclers of red cell iron (reticuloendothelial macrophages). Interactions between iron and copper in the brain are also discussed. Many unanswered questions regarding the role of these metals and their interactions in health and disease emerge from this synopsis, highlighting extensive future research opportunities. PMID:20384844

Pseudomonas aeruginosa adapts its iron uptake strategies in function of the type of infections

PubMed Central

Cornelis, Pierre; Dingemans, Jozef

2013-01-01

Pseudomonas aeruginosa is a Gram-negative γ-Proteobacterium which is known for its capacity to colonize various niches, including some invertebrate and vertebrate hosts, making it one of the most frequent bacteria causing opportunistic infections. P. aeruginosa is able to cause acute as well as chronic infections and it uses different colonization and virulence factors to do so. Infections range from septicemia, urinary infections, burn wound colonization, and chronic colonization of the lungs of cystic fibrosis patients. Like the vast majority of organisms, P. aeruginosa needs iron to sustain growth. P. aeruginosa utilizes different strategies to take up iron, depending on the type of infection it causes. Two siderophores are produced by this bacterium, pyoverdine and pyochelin, characterized by high and low affinities for iron respectively. P. aeruginosa is also able to utilize different siderophores from other microorganisms (siderophore piracy). It can also take up heme from hemoproteins via two different systems. Under microaerobic or anaerobic conditions, P. aeruginosa is also able to take up ferrous iron via its Feo system using redox-cycling phenazines. Depending on the type of infection, P. aeruginosa can therefore adapt by switching from one iron uptake system to another as we will describe in this short review. PMID:24294593

Regulation of cellular iron metabolism

PubMed Central

Wang, Jian; Pantopoulos, Kostas

2011-01-01

Iron is an essential but potentially hazardous biometal. Mammalian cells require sufficient amounts of iron to satisfy metabolic needs or to accomplish specialized functions. Iron is delivered to tissues by circulating transferrin, a transporter that captures iron released into the plasma mainly from intestinal enterocytes or reticuloendothelial macrophages. The binding of iron-laden transferrin to the cell-surface transferrin receptor 1 results in endocytosis and uptake of the metal cargo. Internalized iron is transported to mitochondria for the synthesis of haem or iron–sulfur clusters, which are integral parts of several metalloproteins, and excess iron is stored and detoxified in cytosolic ferritin. Iron metabolism is controlled at different levels and by diverse mechanisms. The present review summarizes basic concepts of iron transport, use and storage and focuses on the IRE (iron-responsive element)/IRP (iron-regulatory protein) system, a well known post-transcriptional regulatory circuit that not only maintains iron homoeostasis in various cell types, but also contributes to systemic iron balance. PMID:21348856

Bmp6 Expression in Murine Liver Non Parenchymal Cells: A Mechanism to Control their High Iron Exporter Activity and Protect Hepatocytes from Iron Overload?

PubMed Central

Rausa, Marco; Pagani, Alessia; Nai, Antonella; Campanella, Alessandro; Gilberti, Maria Enrica; Apostoli, Pietro; Camaschella, Clara; Silvestri, Laura

2015-01-01

Bmp6 is the main activator of hepcidin, the liver hormone that negatively regulates plasma iron influx by degrading the sole iron exporter ferroportin in enterocytes and macrophages. Bmp6 expression is modulated by iron but the molecular mechanisms are unknown. Although hepcidin is expressed almost exclusively by hepatocytes (HCs), Bmp6 is produced also by non-parenchymal cells (NPCs), mainly sinusoidal endothelial cells (LSECs). To investigate the regulation of Bmp6 in HCs and NPCs, liver cells were isolated from adult wild type mice whose diet was modified in iron content in acute or chronic manner and in disease models of iron deficiency (Tmprss6 KO mouse) and overload (Hjv KO mouse). With manipulation of dietary iron in wild-type mice, Bmp6 and Tfr1 expression in both HCs and NPCs was inversely related, as expected. When hepcidin expression is abnormal in murine models of iron overload (Hjv KO mice) and deficiency (Tmprss6 KO mice), Bmp6 expression in NPCs was not related to Tfr1. Despite the low Bmp6 in NPCs from Tmprss6 KO mice, Tfr1 mRNA was also low. Conversely, despite body iron overload and high expression of Bmp6 in NPCs from Hjv KO mice, Tfr1 mRNA and protein were increased. However, in the same cells ferritin L was only slightly increased, but the iron content was not, suggesting that Bmp6 in these cells reflects the high intracellular iron import and export. We propose that NPCs, sensing the iron flux, not only increase hepcidin through Bmp6 with a paracrine mechanism to control systemic iron homeostasis but, controlling hepcidin, they regulate their own ferroportin, inducing iron retention or release and further modulating Bmp6 production in an autocrine manner. This mechanism, that contributes to protect HC from iron loading or deficiency, is lost in disease models of hepcidin production. PMID:25860887

Iron Acquisition in Bacillus cereus: The Roles of IlsA and Bacillibactin in Exogenous Ferritin Iron Mobilization

PubMed Central

Buisson, Christophe; Daou, Nadine; Kallassy, Mireille; Lereclus, Didier; Arosio, Paolo; Bou-Abdallah, Fadi; Nielsen Le Roux, Christina

2014-01-01

In host-pathogen interactions, the struggle for iron may have major consequences on the outcome of the disease. To overcome the low solubility and bio-availability of iron, bacteria have evolved multiple systems to acquire iron from various sources such as heme, hemoglobin and ferritin. The molecular basis of iron acquisition from heme and hemoglobin have been extensively studied; however, very little is known about iron acquisition from host ferritin, a 24-mer nanocage protein able to store thousands of iron atoms within its cavity. In the human opportunistic pathogen Bacillus cereus, a surface protein named IlsA (Iron-regulated leucine rich surface protein type A) binds heme, hemoglobin and ferritin in vitro and is involved in virulence. Here, we demonstrate that IlsA acts as a ferritin receptor causing ferritin aggregation on the bacterial surface. Isothermal titration calorimetry data indicate that IlsA binds several types of ferritins through direct interaction with the shell subunits. UV-vis kinetic data show a significant enhancement of iron release from ferritin in the presence of IlsA indicating for the first time that a bacterial protein might alter the stability of the ferritin iron core. Disruption of the siderophore bacillibactin production drastically reduces the ability of B. cereus to utilize ferritin for growth and results in attenuated bacterial virulence in insects. We propose a new model of iron acquisition in B. cereus that involves the binding of IlsA to host ferritin followed by siderophore assisted iron uptake. Our results highlight a possible interplay between a surface protein and a siderophore and provide new insights into host adaptation of B. cereus and general bacterial pathogenesis. PMID:24550730

Functional analysis of an feoB mutant in Clostridium perfringens strain 13.

PubMed

Awad, Milena M; Cheung, Jackie K; Tan, Joanne E; McEwan, Alastair G; Lyras, Dena; Rood, Julian I

2016-10-01

Bacterial pathogens have adopted numerous mechanisms for acquiring iron from host proteins during an infection, including the direct acquisition of ferric iron from heme-associated proteins or from iron-scavenging siderophores. Ferric iron then is transported into the cytosol, where it can be utilized by the bacterial pathogen. Under anaerobic conditions bacteria can also transport ferrous iron using the transmembrane complex FeoAB, but little is known about iron transport systems in anaerobic bacteria such as the pathogenic clostridia. In this study we sought to characterize the iron acquisition process in Clostridium perfringens. Bioinformatic analysis of the Clostridium perfringens strain 13 genome sequence revealed that it has seven potential iron acquisition systems: three siderophore-mediated systems, one ferric citrate uptake system, two heme-associated acquisition systems and one ferrous iron uptake system (FeoAB). The relative level of expression of these systems was determined using quantitative real-time RT-PCR assays that were specific for one gene from each system. Each of these genes was expressed, with the feoAB genes generating the most abundant iron-uptake related transcripts. To further examine the role of this system in the growth of C. perfringens, insertional inactivation was used to isolate a chromosomal feoB mutant. Growth of this mutant in the presence and absence of iron revealed that it had altered growth properties and a markedly reduced total iron and manganese content compared to the wild type; effects that were reversed upon complementation with the wild-type feoB gene. These studies suggest that under anaerobic conditions FeoB is the major protein required for the uptake of iron into the cell and that it may play an important role in the pathogenesis of C. perfringens infections. Copyright © 2016 Elsevier Ltd. All rights reserved.

Iron-Regulated Expression of Alginate Production, Mucoid Phenotype, and Biofilm Formation by Pseudomonas aeruginosa

PubMed Central

Wiens, Jacinta R.; Vasil, Adriana I.; Schurr, Michael J.; Vasil, Michael L.

2014-01-01

ABSTRACT Pseudomonas aeruginosa strains of non-cystic fibrosis (non-CF) origin do not produce significant amounts of extracellular alginate and are nonmucoid. In CF, such isolates can become mucoid through mutation of one of the genes (mucA, mucB, mucC, or mucD) that produce regulatory factors that sequester AlgU, required for increased expression of alginate genes. Mutation of the muc genes in the nonmucoid PAO1, PA14, PAKS-1, and Ps388 strains led to increased levels of extracellular alginate and an obvious mucoid phenotype, but only under iron-limiting growth conditions (≤5 µM), not under iron-replete conditions (≥10 µM). In contrast, >50% of P. aeruginosa isolates from chronic CF pulmonary infections expressed increased levels of alginate and mucoidy both under iron-limiting and iron-replete conditions (i.e., iron-constitutive phenotype). No single iron regulatory factor (e.g., Fur, PvdS) was associated with this loss of iron-regulated alginate expression and mucoidy in these CF isolates. However, the loss of only pyoverdine production, or its uptake, abrogated the ability of P. aeruginosa to produce a robust biofilm that represents the Psl-type of biofilm. In contrast, we show that mutation of the pyoverdine and pyochelin biosynthesis genes and the pyoverdine receptor (FpvA) lead to iron-constitutive expression of the key alginate biosynthesis gene, algD, and an explicitly mucoid phenotype in both iron-limiting and iron-replete conditions. These data indicate that alginate production and mucoidy, in contrast to other types of biofilms produced by P. aeruginosa, are substantially enhanced under iron limitation. These results also have compelling implications in relation to the use of iron chelators in the treatment of P. aeruginosa CF infections. PMID:24496793

Solar abundance ratios of the iron-peak elements in the Perseus cluster.

PubMed

2017-11-23

The metal abundance of the hot plasma that permeates galaxy clusters represents the accumulation of heavy elements produced by billions of supernovae. Therefore, X-ray spectroscopy of the intracluster medium provides an opportunity to investigate the nature of supernova explosions integrated over cosmic time. In particular, the abundance of the iron-peak elements (chromium, manganese, iron and nickel) is key to understanding how the progenitors of typical type Ia supernovae evolve and explode. Recent X-ray studies of the intracluster medium found that the abundance ratios of these elements differ substantially from those seen in the Sun, suggesting differences between the nature of type Ia supernovae in the clusters and in the Milky Way. However, because the K-shell transition lines of chromium and manganese are weak and those of iron and nickel are very close in photon energy, high-resolution spectroscopy is required for an accurate determination of the abundances of these elements. Here we report observations of the Perseus cluster, with statistically significant detections of the resonance emission from chromium, manganese and nickel. Our measurements, combined with the latest atomic models, reveal that these elements have near-solar abundance ratios with respect to iron, in contrast to previous claims. Comparison between our results and modern nucleosynthesis calculations disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4 times the mass of the Sun). The observed abundance pattern of the iron-peak elements can be explained by taking into account a combination of near- and sub-Chandrasekhar-mass type Ia supernova systems, adding to the mounting evidence that both progenitor types make a substantial contribution to cosmic chemical enrichment.

Solar abundance ratios of the iron-peak elements in the Perseus cluster

DOE PAGES

Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; ...

2017-11-13

The metal abundance of the hot plasma that permeates galaxy clusters represents the accumulation of heavy elements produced by billions of supernovae1. Therefore, X-ray spectroscopy of the intracluster medium provides an opportunity to investigate the nature of supernova explosions integrated over cosmic time. In particular, the abundance of the iron-peak elements (chromium, manganese, iron and nickel) is key to understanding how the progenitors of typical type Ia supernovae evolve and explode2–6. Recent X-ray studies of the intracluster medium found that the abundance ratios of these elements differ substantially from those seen in the Sun, suggesting differences between the nature ofmore » type Ia supernovae in the clusters and in the Milky Way. However, because the K-shell transition lines of chromium and manganese are weak and those of iron and nickel are very close in photon energy, highresolution spectroscopy is required for an accurate determination of the abundances of these elements. Here in this paper we report observations of the Perseus cluster, with statistically significant detections of the resonance emission from chromium, manganese and nickel. Our measurements, combined with the latest atomic models, reveal that these elements have near-solar abundance ratios with respect to iron, in contrast to previous claims. Comparison between our results and modern nucleosynthesis calculations disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4 times the mass of the Sun). The observed abundance pattern of the iron-peak elements can be explained by taking into account a combination of near- and sub-Chandrasekhar-mass type Ia supernova systems, adding to the mounting evidence that both progenitor types make a substantial contribution to cosmic chemical enrichment.« less

Solar abundance ratios of the iron-peak elements in the Perseus cluster

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie

The metal abundance of the hot plasma that permeates galaxy clusters represents the accumulation of heavy elements produced by billions of supernovae1. Therefore, X-ray spectroscopy of the intracluster medium provides an opportunity to investigate the nature of supernova explosions integrated over cosmic time. In particular, the abundance of the iron-peak elements (chromium, manganese, iron and nickel) is key to understanding how the progenitors of typical type Ia supernovae evolve and explode2–6. Recent X-ray studies of the intracluster medium found that the abundance ratios of these elements differ substantially from those seen in the Sun, suggesting differences between the nature ofmore » type Ia supernovae in the clusters and in the Milky Way. However, because the K-shell transition lines of chromium and manganese are weak and those of iron and nickel are very close in photon energy, highresolution spectroscopy is required for an accurate determination of the abundances of these elements. Here in this paper we report observations of the Perseus cluster, with statistically significant detections of the resonance emission from chromium, manganese and nickel. Our measurements, combined with the latest atomic models, reveal that these elements have near-solar abundance ratios with respect to iron, in contrast to previous claims. Comparison between our results and modern nucleosynthesis calculations disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4 times the mass of the Sun). The observed abundance pattern of the iron-peak elements can be explained by taking into account a combination of near- and sub-Chandrasekhar-mass type Ia supernova systems, adding to the mounting evidence that both progenitor types make a substantial contribution to cosmic chemical enrichment.« less

Iron regulation of hepcidin despite attenuated Smad1,5,8 signaling in mice without transferrin receptor 2 or Hfe

PubMed Central

Corradini, Elena; Rozier, Molly; Meynard, Delphine; Odhiambo, Adam; Lin, Herbert Y.; Feng, Qi; Migas, Mary C.; Britton, Robert S.; Babitt, Jodie L.; Fleming, Robert E.

2011-01-01

Background & Aims HFE and transferrin receptor 2 (TFR2) are each necessary for the normal relationship between body iron status and liver hepcidin expression. In murine Hfe and Tfr2 knockout models of hereditary hemochromatosis (HH), signal transduction to hepcidin via the bone morphogenetic protein 6 (Bmp6)/Smad1,5,8 pathway is attenuated. We examined the effect of dietary iron on regulation of hepcidin expression via the Bmp6/Smad1,5,8 pathway using mice with targeted disruption of Tfr2, Hfe, or both genes. Methods Hepatic iron concentrations and mRNA expression of Bmp6 and hepcidin were compared with wild-type mice in each of the HH models on standard or iron-loading diets. Liver phospho-Smad (P-Smad)1,5,8 and Id1 mRNA levels were measured as markers of Bmp/Smad signaling. Results While Bmp6 expression was increased, liver hepcidin and Id1 expression were decreased in each of the HH models compared with wild-type mice. Each of the HH models also demonstrated attenuated P-Smad1,5,8 levels relative to liver iron status. Mice with combined Hfe/Tfr2 disruption were most affected. Dietary iron loading increased hepcidin and Id1 expression in each of the HH models. Compared with wild-type mice, HH mice demonstrated attenuated (Hfe knockout) or no increases in P-Smad1,5,8 levels in response to dietary iron loading. Conclusions These observations demonstrate that Tfr2 and Hfe are each required for normal signaling of iron status to hepcidin via Bmp6/Smad1,5,8 pathway. Mice with combined loss of Hfe and Tfr2 up-regulate hepcidin in response to dietary iron loading without increases in liver BMP6 mRNA or steady-state P-Smad1,5,8 levels. PMID:21745449

Histopathology of mallards dosed with lead and selected substitute shot

USGS Publications Warehouse

Locke, L.N.; Irby, H.D.; Bagley, George E.

1967-01-01

The histopathological response of male game farm mallards fed lead, three types of plastic-coated lead, two lead-magnesium alloys, iron, copper, zinc-coated iron, and molybdenum-coated iron shot was studied. Mallards fed lead, plastic-coated lead, or lead-magnesium alloy shot developed a similar pathological response, including the formation of acid-fast intranuclear inclusion bodies in the kidneys. Birds fed iron or molybdenum-coated iron shot developed hemosiderosis of the liver. Two of four mallards fed zinc-coated iron shot also developed hemosiderosis of the liver. No lesions were found in mallards fed copper shot.

Upgrade Recycling of Cast Iron Scrap Chips towards β-FeSi₂ Thermoelectric Materials.

PubMed

Laila, Assayidatul; Nanko, Makoto; Takeda, Masatoshi

2014-09-04

The upgrade recycling of cast-iron scrap chips towards β-FeSi₂ thermoelectric materials is proposed as an eco-friendly and cost-effective production process. By using scrap waste from the machining process of cast-iron components, the material cost to fabricate β-FeSi₂ is reduced and the industrial waste is recycled. In this study, β-FeSi₂ specimens obtained from cast iron scrap chips were prepared both in the undoped form and doped with Al and Co elements. The maximum figure of merit ( ZT ) indicated a thermoelectric performance of approximately 70% in p-type samples and nearly 90% in n-type samples compared to β-FeSi₂ prepared from pure Fe and other published studies. The use of cast iron scrap chips to produce β-FeSi₂ shows promise as an eco-friendly and cost-effective production process for thermoelectric materials.

The Bordetella bhu Locus Is Required for Heme Iron Utilization

PubMed Central

Vanderpool, Carin K.; Armstrong, Sandra K.

2001-01-01

Bordetella pertussis and Bordetella bronchiseptica are capable of obtaining iron from hemin and hemoglobin. Genes encoding a putative bacterial heme iron acquisition system (bhu, for Bordetella heme utilization) were identified in a B. pertussis genomic sequence database, and the corresponding DNA was isolated from a virulent strain of B. pertussis. A B. pertussis bhuR mutant, predicted to lack the heme outer membrane receptor, was generated by allelic exchange. In contrast to the wild-type strain, bhuR mutant PM5 was incapable of acquiring iron from hemin and hemoglobin; genetic complementation of PM5 with the cloned bhuRSTUV genes restored heme utilization to wild-type levels. In parallel studies, B. bronchiseptica bhu sequences were also identified and a B. bronchiseptica bhuR mutant was constructed and confirmed to be defective in heme iron acquisition. The wild-type B. bronchiseptica parent strain grown under low-iron conditions produced the presumptive BhuR protein, which was absent in the bhuR mutant. Furthermore, production of BhuR by iron-starved B. bronchiseptica was markedly enhanced by culture in hemin-supplemented medium, suggesting that these organisms sense and respond to heme in the environment. Analysis of the genetic region upstream of the bhu cluster identified open reading frames predicted to encode homologs of the Escherichia coli ferric citrate uptake regulators FecI and FecR. These putative Bordetella regulators may mediate heme-responsive positive transcriptional control of the bhu genes. PMID:11418569

Tuning Amphiphilicity of Particles for Controllable Pickering Emulsion

PubMed Central

Wang, Zhen; Wang, Yapei

2016-01-01

Pickering emulsions with the use of particles as emulsifiers have been extensively used in scientific research and industrial production due to their edge in biocompatibility and stability compared with traditional emulsions. The control over Pickering emulsion stability and type plays a significant role in these applications. Among the present methods to build controllable Pickering emulsions, tuning the amphiphilicity of particles is comparatively effective and has attracted enormous attention. In this review, we highlight some recent advances in tuning the amphiphilicity of particles for controlling the stability and type of Pickering emulsions. The amphiphilicity of three types of particles including rigid particles, soft particles, and Janus particles are tailored by means of different mechanisms and discussed here in detail. The stabilization-destabilization interconversion and phase inversion of Pickering emulsions have been successfully achieved by changing the surface properties of these particles. This article provides a comprehensive review of controllable Pickering emulsions, which is expected to stimulate inspiration for designing and preparing novel Pickering emulsions, and ultimately directing the preparation of functional materials. PMID:28774029

Formulation and Stabilization of Concentrated Edible Oil-in-Water Emulsions Based on Electrostatic Complexes of a Food-Grade Cationic Surfactant (Ethyl Lauroyl Arginate) and Cellulose Nanocrystals.

PubMed

Bai, Long; Xiang, Wenchao; Huan, Siqi; Rojas, Orlando J

2018-05-14

We report on high-internal-phase, oil-in-water Pickering emulsions that are stable against coalescence during storage. Viscous, edible oil (sunflower) was emulsified by combining naturally derived cellulose nanocrystals (CNCs) and a food-grade, biobased cationic surfactant obtained from lauric acid and L-arginine (ethyl lauroyl arginate, LAE). The interactions between CNC and LAE were elucidated by isothermal titration calorimetry (ITC) and supplementary techniques. LAE adsorption on CNC surfaces and its effect on nanoparticle electrostatic stabilization, aggregation state, and emulsifying ability was studied and related to the properties of resultant oil-in-water emulsions. Pickering systems with tunable droplet diameter and stability against oil coalescence during long-term storage were controllably achieved depending on LAE loading. The underlying stabilization mechanism was found to depend on the type of complex formed, the LAE structures adsorbed on the cellulose nanoparticles (as unimer or as adsorbed admicelles), the presence of free LAE in the aqueous phase, and the equivalent alkane number of the oil phase (sunflower and dodecane oils were compared). The results extend the potential of CNC in the formulation of high-quality and edible Pickering emulsions. The functional properties imparted by LAE, a highly effective molecule against food pathogens and spoilage organisms, open new opportunities in food, cosmetics, and pharmaceutical applications, where the presence of CNC plays a critical role in achieving synergistic effects with LAE.

Physicochemical Properties and Chemical Stability of β-Carotene Bilayer Emulsion Coated with Bovine Serum Albumin and Arabic Gum Compared to Monolayer Emulsions.

PubMed

Sheng, Bulei; Li, Lin; Zhang, Xia; Jiao, Wenjuan; Zhao, Di; Wang, Xue; Wan, Liting; Li, Bing; Rong, Hui

2018-02-23

β-carotene is a lipophilic micronutrient that is considered beneficial to human health. However, there are some limitations in utilizing β-carotene in functional foods or dietary supplements currently because of its poor water dispersibility and chemical stability. A new type of β-carotene bilayer emulsion delivery system was prepared by a layer-by-layer electrostatic deposition technique, for which were chosen bovine serum albumin (BSA) as the inner emulsifier and Arabic gum (GA) as the outer emulsifier. The physicochemical properties of bilayer emulsions were mainly characterized by droplet size distribution, zeta potential, rheological behavior, Creaming Index (CI), and encapsulation ratio of β-carotene. Besides this, the effects of processing conditions (pH, thermal treatment, UV radiation, strong oxidant) and storage time on the chemical stability of bilayer emulsions were also evaluated. The bilayer emulsion had a small droplet size (221.27 ± 5.17 nm) and distribution (PDI = 0.23 ± 0.02), strong zeta potential (-30.37 ± 0.71 mV), good rheological behavior (with the highest viscosity that could reduce the possibility of flocculation) and physical stability (CI = 0), high β-carotene encapsulation ratio (94.35 ± 0.71%), and low interfacial tension (40.81 ± 0.86 mN/m). It also obtained better chemical stability under different environmental stresses when compared with monolayer emulsions studied, because it had a dense and thick bilayer structure.

Bioremediation in fractured rock: 1. Modeling to inform design, monitoring, and expectations

USGS Publications Warehouse

Tiedeman, Claire; Shapiro, Allen M.; Hsieh, Paul A.; Imbrigiotta, Thomas; Goode, Daniel J.; Lacombe, Pierre; DeFlaun, Mary F.; Drew, Scott R.; Johnson, Carole D.; Williams, John H.; Curtis, Gary P.

2018-01-01

Field characterization of a trichloroethene (TCE) source area in fractured mudstones produced a detailed understanding of the geology, contaminant distribution in fractures and the rock matrix, and hydraulic and transport properties. Groundwater flow and chemical transport modeling that synthesized the field characterization information proved critical for designing bioremediation of the source area. The planned bioremediation involved injecting emulsified vegetable oil and bacteria to enhance the naturally occurring biodegradation of TCE. The flow and transport modeling showed that injection will spread amendments widely over a zone of lower‐permeability fractures, with long residence times expected because of small velocities after injection and sorption of emulsified vegetable oil onto solids. Amendments transported out of this zone will be diluted by groundwater flux from other areas, limiting bioremediation effectiveness downgradient. At nearby pumping wells, further dilution is expected to make bioremediation effects undetectable in the pumped water. The results emphasize that in fracture‐dominated flow regimes, the extent of injected amendments cannot be conceptualized using simple homogeneous models of groundwater flow commonly adopted to design injections in unconsolidated porous media (e.g., radial diverging or dipole flow regimes). Instead, it is important to synthesize site characterization information using a groundwater flow model that includes discrete features representing high‐ and low‐permeability fractures. This type of model accounts for the highly heterogeneous hydraulic conductivity and groundwater fluxes in fractured‐rock aquifers, and facilitates designing injection strategies that target specific volumes of the aquifer and maximize the distribution of amendments over these volumes.

Effect of formulation variables on design, in vitro evaluation of valsartan SNEDDS and estimation of its antioxidant effect in adrenaline-induced acute myocardial infarction in rats.

PubMed

Amin, Maha M; El Gazayerly, Omaima N; Abd El-Gawad, Nabaweya A; Abd El-Halim, Shady M; El-Awdan, Sally A

2016-12-01

Valsartan is a specific angiotensin II antagonist used for the treatment of hypertension. It suffers from low aqueous solubility and high variability in its absorption after oral administration. The aim of this study was to improve the dissolution and thereby the bioavailability of Valsartan through the development of self nano-emulsifying drug delivery systems. Four ternary phase diagrams were constructed to identify the self-emulsification region of Capmul® MCM, Labrafil® M1944, Capryol™ 90 and Labrafac® PG together with Cremophore® RH 40 and Transcutol™ HP as oil, surfactant and co-surfactant, respectively. The effect of oil type, oil and surfactant concentration on droplet size and in vitro Valsartan dissolution were studied. The protective effect of the optimum formula F5 in adrenaline-induced oxidative stress in rats during myocardial infarction was determined. Formula F5 exhibited globule size of (13.95 nm) with 76.07% ± 1.10 of Valsartan dissolved after five minutes compared to Disartan 80 mg capsules (13.43%). Results revealed a significant reduction (p < 0.05) in serum aspartate transaminase, creatine kinase myocardial band and malondialdehyde levels, while a significant increase (p < 0.05) in serum glutathione in F5. Therefore, self nano-emulsifying drug delivery systems could be considered as a promising approach to improve the dissolution and thereby the bioavailability of Valsartan.

Iron-oxide minerals affect extracellular electron-transfer paths of Geobacter spp.

PubMed

Kato, Souichiro; Hashimoto, Kazuhito; Watanabe, Kazuya

2013-01-01

Some bacteria utilize (semi)conductive iron-oxide minerals as conduits for extracellular electron transfer (EET) to distant, insoluble electron acceptors. A previous study demonstrated that microbe/mineral conductive networks are constructed in soil ecosystems, in which Geobacter spp. share dominant populations. In order to examine how (semi)conductive iron-oxide minerals affect EET paths of Geobacter spp., the present study grew five representative Geobacter strains on electrodes as the sole electron acceptors in the absence or presence of (semi)conductive iron oxides. It was found that iron-oxide minerals enhanced current generation by three Geobacter strains, while no effect was observed in another strain. Geobacter sulfurreducens was the only strain that generated substantial amounts of currents both in the presence and absence of the iron oxides. Microscopic, electrochemical and transcriptomic analyses of G. sulfurreducens disclosed that this strain constructed two distinct types of EET path; in the absence of iron-oxide minerals, bacterial biofilms rich in extracellular polymeric substances were constructed, while composite networks made of mineral particles and microbial cells (without polymeric substances) were developed in the presence of iron oxides. It was also found that uncharacterized c-type cytochromes were up-regulated in the presence of iron oxides that were different from those found in conductive biofilms. These results suggest the possibility that natural (semi)conductive minerals confer energetic and ecological advantages on Geobacter, facilitating their growth and survival in the natural environment.

Plasma secretin, plasma cholecystokinin, pancreaticobiliary secretion, and fat absorption: effect of duodenal osmolality and polysorbate 80.

PubMed

Olsen, O; Schaffalitzky de Muckadell, O B; Cantor, P

1987-11-01

In 20 normal persons we investigated the effects of duodenal osmolality on the release of secretin and cholecystokinin (CCK), pancreaticobiliary secretion, and fat absorption after intestinal infusion of emulsified oleic acid (pH 6.0). The release of CCK was found to be unaffected by the changes in osmolality, whereas the plasma levels of secretin were affected in parallel with volume and bicarbonate secretion. An inverse relation was found between fatty acid absorption and release of secretin and bicarbonate secretion but not between fatty acid absorption and release of CCK. It is suggested that the secretin and CCK cells respond differently to emulsified oleic acid.

Properties of protein powders from arrowtooth flounder (Atheresthes stomias) and herring (Clupea harengus) byproducts.

PubMed

Sathivel, Subramaniam; Bechtel, Peter J; Babbitt, Jerry; Prinyawiwatkul, Witoon; Negulescu, Ioan I; Reppond, Kermit D

2004-08-11

Functional, nutritional, and thermal properties of freeze-dried protein powders (FPP) from whole herring (WHP), herring body (HBP), herring head (HHP), herring gonad (HGP), and arrowtooth flounder fillets (AFP) were evaluated. The FPP samples have desirable nutritional and functional properties and contained 63-81.4% protein. All FPP samples had desirable essential amino acid profiles and mineral contents. The emulsifying and fat adsorption capacities of all FPP samples were higher than those of soy protein concentrate. The emulsifying stability of WHP was lower than that of egg albumin but greater than that of soy protein concentrate. Thermal stability of the FPP samples is in the following order: HGP > HBP > WHP > HHP > AFP.

Iron Overload Accelerates the Progression of Diabetic Retinopathy in Association with Increased Retinal Renin Expression.

PubMed

Chaudhary, Kapil; Promsote, Wanwisa; Ananth, Sudha; Veeranan-Karmegam, Rajalakshmi; Tawfik, Amany; Arjunan, Pachiappan; Martin, Pamela; Smith, Sylvia B; Thangaraju, Muthusamy; Kisselev, Oleg; Ganapathy, Vadivel; Gnana-Prakasam, Jaya P

2018-02-14

Diabetic retinopathy (DR) is a leading cause of blindness among working-age adults. Increased iron accumulation is associated with several degenerative diseases. However, there are no reports on the status of retinal iron or its implications in the pathogenesis of DR. In the present study, we found that retinas of type-1 and type-2 mouse models of diabetes have increased iron accumulation compared to non-diabetic retinas. We found similar iron accumulation in postmortem retinal samples from human diabetic patients. Further, we induced diabetes in HFE knockout (KO) mice model of genetic iron overload to understand the role of iron in the pathogenesis of DR. We found increased neuronal cell death, vascular alterations and loss of retinal barrier integrity in diabetic HFE KO mice compared to diabetic wildtype mice. Diabetic HFE KO mouse retinas also exhibited increased expression of inflammation and oxidative stress markers. Severity in the pathogenesis of DR in HFE KO mice was accompanied by increase in retinal renin expression mediated by G-protein-coupled succinate receptor GPR91. In light of previous reports implicating retinal renin-angiotensin system in DR pathogenesis, our results reveal a novel relationship between diabetes, iron and renin-angiotensin system, thereby unraveling new therapeutic targets for the treatment of DR.

Evaluation of constitutive iron reductase (AtFRO2) expression on mineral accumulation and distribution in soybean (Glycine max. L)

PubMed Central

Vasconcelos, Marta W.; Clemente, Thomas E.; Grusak, Michael A.

2014-01-01

Iron is an important micronutrient in human and plant nutrition. Adequate iron nutrition during crop production is central for assuring appropriate iron concentrations in the harvestable organs, for human food or animal feed. The whole-plant movement of iron involves several processes, including the reduction of ferric to ferrous iron at several locations throughout the plant, prior to transmembrane trafficking of ferrous iron. In this study, soybean plants that constitutively expressed the AtFRO2 iron reductase gene were analyzed for leaf iron reductase activity, as well as the effect of this transgene’s expression on root, leaf, pod wall, and seed mineral concentrations. High Fe supply, in combination with the constitutive expression of AtFRO2, resulted in significantly higher concentrations of different minerals in roots (K, P, Zn, Ca, Ni, Mg, and Mo), pod walls (Fe, K, P, Cu, and Ni), leaves (Fe, P, Cu, Ca, Ni, and Mg) and seeds (Fe, Zn, Cu, and Ni). Leaf and pod wall iron concentrations increased as much as 500% in transgenic plants, while seed iron concentrations only increased by 10%, suggesting that factors other than leaf and pod wall reductase activity were limiting the translocation of iron to seeds. Protoplasts isolated from transgenic leaves had three-fold higher reductase activity than controls. Expression levels of the iron storage protein, ferritin, were higher in the transgenic leaves than in wild-type, suggesting that the excess iron may be stored as ferritin in the leaves and therefore unavailable for phloem loading and delivery to the seeds. Also, citrate and malate levels in the roots and leaves of transgenic plants were significantly higher than in wild-type, suggesting that organic acid production could be related to the increased accumulation of minerals in roots, leaves, and pod walls, but not in the seeds. All together, these results suggest a more ubiquitous role for the iron reductase in whole-plant mineral accumulation and distribution. PMID:24765096

Ferritin and ferrihydrite nanoparticles as iron sources for Pseudomonas aeruginosa

PubMed Central

Dehner, Carolyn; Morales-Soto, Nydia; Behera, Rabindra K.; Shrout, Joshua; Theil, Elizabeth C.; Maurice, Patricia A.

2013-01-01

Metabolism of iron derived from insoluble and/ or scarce sources is essential for pathogenic and environmental microbes. The ability of Pseudomonas aeruginosa to acquire iron from exogenous ferritin was assessed; ferritin is an iron-concentrating and antioxidant protein complex composed of a catalytic protein and caged ferrihydrite nanomineral synthesized from Fe(II) and O2 or H2O2. Ferritin and free ferrihydrite supported growth of P. aeruginosa with indistinguishable kinetics and final culture densities. The P. aeruginosa PAO1 mutant (ΔpvdDΔpchEF), which is incapable of siderophore production, grew as well as the wild type when ferritin was the iron source. Such data suggest that P. aeruginosa can acquire iron by siderophore-independent mechanisms, including secretion of small-molecule reductant(s). Protease inhibitors abolished the growth of the siderophore-free strain on ferritins, with only a small effect on growth of the wild type; predictably, protease inhibitors had no effect on growth with free ferrihydrite as the iron source. Proteolytic activity was higher with the siderophore-free strain, suggesting that the role of proteases in the degradation of ferritin is particularly important for iron acquisition in the absence of siderophores. The combined results demonstrate the importance of both free ferrihydrite, a natural environmental form of iron and a model for an insoluble form of partly denatured ferritin called hemosiderin, and caged ferritin iron minerals as bacterial iron sources. Ferritin is also revealed as a growth promoter of opportunistic, pathogenic bacteria such a P. aeruginosa in diseased tissues such as the cystic fibrotic lung, where ferritin concentrations are abnormally high. PMID:23417538

Secreted glyceraldehye-3-phosphate dehydrogenase is a multifunctional autocrine transferrin receptor for cellular iron acquisition.

PubMed

Sheokand, Navdeep; Kumar, Santosh; Malhotra, Himanshu; Tillu, Vikas; Raje, Chaaya Iyengar; Raje, Manoj

2013-06-01

The long held view is that mammalian cells obtain transferrin (Tf) bound iron utilizing specialized membrane anchored receptors. Here we report that, during increased iron demand, cells secrete the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) which enhances cellular uptake of Tf and iron. These observations could be mimicked by utilizing purified GAPDH injected into mice as well as when supplemented in culture medium of model cell lines and primary cell types that play a key role in iron metabolism. Transferrin and iron delivery was evaluated by biochemical, biophysical and imaging based assays. This mode of iron uptake is a saturable, energy dependent pathway, utilizing raft as well as non-raft domains of the cell membrane and also involves the membrane protein CD87 (uPAR). Tf internalized by this mode is also catabolized. Our research demonstrates that, even in cell types that express the known surface receptor based mechanism for transferrin uptake, more transferrin is delivered by this route which represents a hidden dimension of iron homeostasis. Iron is an essential trace metal for practically all living organisms however its acquisition presents major challenges. The current paradigm is that living organisms have developed well orchestrated and evolved mechanisms involving iron carrier molecules and their specific receptors to regulate its absorption, transport, storage and mobilization. Our research uncovers a hidden and primitive pathway of bulk iron trafficking involving a secreted receptor that is a multifunctional glycolytic enzyme that has implications in pathological conditions such as infectious diseases and cancer. Copyright © 2013 Elsevier B.V. All rights reserved.

Understanding metal homeostasis in primary cultured neurons. Studies using single neuron subcellular and quantitative metallomics.

PubMed

Colvin, Robert A; Lai, Barry; Holmes, William R; Lee, Daewoo

2015-07-01

The purpose of this study was to demonstrate how single cell quantitative and subcellular metallomics inform us about both the spatial distribution and cellular mechanisms of metal buffering and homeostasis in primary cultured neurons from embryonic rat brain, which are often used as models of human disease involving metal dyshomeostasis. The present studies utilized synchrotron radiation X-ray fluorescence (SRXRF) and focused primarily on zinc and iron, two abundant metals in neurons that have been implicated in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Total single cell contents for calcium, iron, zinc, copper, manganese, and nickel were determined. Resting steady state zinc showed a diffuse distribution in both soma and processes, best defined by the mass profile of the neuron with an enrichment in the nucleus compared with the cytoplasm. Zinc buffering and homeostasis was studied using two modes of cellular zinc loading - transporter and ionophore (pyrithione) mediated. Single neuron zinc contents were shown to statistically significantly increase by either loading method - ionophore: 160 million to 7 billion; transporter 160 million to 280 million atoms per neuronal soma. The newly acquired and buffered zinc still showed a diffuse distribution. Soma and processes have about equal abilities to take up zinc via transporter mediated pathways. Copper levels are distributed diffusely as well, but are relatively higher in the processes relative to zinc levels. Prior studies have observed iron puncta in certain cell types, but others have not. In the present study, iron puncta were characterized in several primary neuronal types. The results show that iron puncta could be found in all neuronal types studied and can account for up to 50% of the total steady state content of iron in neuronal soma. Although other metals can be present in iron puncta, they are predominantly iron containing and do not appear to be associated with ferritin cages or transferrin receptor endosomes. The iron content and its distribution in puncta were similar in all neuron types studied including primary dopaminergic neurons. In summary, quantitative measurements of steady state metal levels in single primary cultured neurons made possible by SRXRF analyses provide unique information on the relative levels of each metal in neuronal soma and processes, subcellular location of zinc loads, and have confirmed and extended the characterization of heretofore poorly understood cytoplasmic iron puncta.

Functional Characterization of the FoxE Iron Oxidoreductase from the Photoferrotroph Rhodobacter ferrooxidans SW2*

PubMed Central

Saraiva, Ivo H.; Newman, Dianne K.; Louro, Ricardo O.

2012-01-01

Photoferrotrophy is presumed to be an ancient type of photosynthetic metabolism in which bacteria use the reducing power of ferrous iron to drive carbon fixation. In this work the putative iron oxidoreductase of the photoferrotroph Rhodobacter ferrooxidans SW2 was cloned, purified, and characterized for the first time. This protein, FoxE, was characterized using spectroscopic, thermodynamic, and kinetic techniques. It is a c-type cytochrome that forms a trimer or tetramer in solution; the two hemes of each monomer are hexacoordinated by histidine and methionine. The hemes have positive reduction potentials that allow downhill electron transfer from many geochemically relevant ferrous iron forms to the photosynthetic reaction center. The reduction potentials of the hemes are different and are cross-assigned to fast and slow kinetic phases of ferrous iron oxidation in vitro. Lower reactivity was observed at high pH and may contribute to prevent ferric iron precipitation inside or at the surface of the cell. These results help fill in the molecular details of a metabolic process that likely contributed to the deposition of precambrian banded iron formations, globally important sedimentary rocks that are found on every continent today. PMID:22661703

Remote-sensing data processing with the multivariate regression analysis method for iron mineral resource potential mapping: a case study in the Sarvian area, central Iran

NASA Astrophysics Data System (ADS)

Mansouri, Edris; Feizi, Faranak; Jafari Rad, Alireza; Arian, Mehran

2018-03-01

This paper uses multivariate regression to create a mathematical model for iron skarn exploration in the Sarvian area, central Iran, using multivariate regression for mineral prospectivity mapping (MPM). The main target of this paper is to apply multivariate regression analysis (as an MPM method) to map iron outcrops in the northeastern part of the study area in order to discover new iron deposits in other parts of the study area. Two types of multivariate regression models using two linear equations were employed to discover new mineral deposits. This method is one of the reliable methods for processing satellite images. ASTER satellite images (14 bands) were used as unique independent variables (UIVs), and iron outcrops were mapped as dependent variables for MPM. According to the results of the probability value (p value), coefficient of determination value (R2) and adjusted determination coefficient (Radj2), the second regression model (which consistent of multiple UIVs) fitted better than other models. The accuracy of the model was confirmed by iron outcrops map and geological observation. Based on field observation, iron mineralization occurs at the contact of limestone and intrusive rocks (skarn type).

Gene co-expression networks shed light into diseases of brain iron accumulation

PubMed Central

Bettencourt, Conceição; Forabosco, Paola; Wiethoff, Sarah; Heidari, Moones; Johnstone, Daniel M.; Botía, Juan A.; Collingwood, Joanna F.; Hardy, John; Milward, Elizabeth A.; Ryten, Mina; Houlden, Henry

2016-01-01

Aberrant brain iron deposition is observed in both common and rare neurodegenerative disorders, including those categorized as Neurodegeneration with Brain Iron Accumulation (NBIA), which are characterized by focal iron accumulation in the basal ganglia. Two NBIA genes are directly involved in iron metabolism, but whether other NBIA-related genes also regulate iron homeostasis in the human brain, and whether aberrant iron deposition contributes to neurodegenerative processes remains largely unknown. This study aims to expand our understanding of these iron overload diseases and identify relationships between known NBIA genes and their main interacting partners by using a systems biology approach. We used whole-transcriptome gene expression data from human brain samples originating from 101 neuropathologically normal individuals (10 brain regions) to generate weighted gene co-expression networks and cluster the 10 known NBIA genes in an unsupervised manner. We investigated NBIA-enriched networks for relevant cell types and pathways, and whether they are disrupted by iron loading in NBIA diseased tissue and in an in vivo mouse model. We identified two basal ganglia gene co-expression modules significantly enriched for NBIA genes, which resemble neuronal and oligodendrocytic signatures. These NBIA gene networks are enriched for iron-related genes, and implicate synapse and lipid metabolism related pathways. Our data also indicates that these networks are disrupted by excessive brain iron loading. We identified multiple cell types in the origin of NBIA disorders. We also found unforeseen links between NBIA networks and iron-related processes, and demonstrate convergent pathways connecting NBIAs and phenotypically overlapping diseases. Our results are of further relevance for these diseases by providing candidates for new causative genes and possible points for therapeutic intervention. PMID:26707700

Gene co-expression networks shed light into diseases of brain iron accumulation.

PubMed

Bettencourt, Conceição; Forabosco, Paola; Wiethoff, Sarah; Heidari, Moones; Johnstone, Daniel M; Botía, Juan A; Collingwood, Joanna F; Hardy, John; Milward, Elizabeth A; Ryten, Mina; Houlden, Henry

2016-03-01

Aberrant brain iron deposition is observed in both common and rare neurodegenerative disorders, including those categorized as Neurodegeneration with Brain Iron Accumulation (NBIA), which are characterized by focal iron accumulation in the basal ganglia. Two NBIA genes are directly involved in iron metabolism, but whether other NBIA-related genes also regulate iron homeostasis in the human brain, and whether aberrant iron deposition contributes to neurodegenerative processes remains largely unknown. This study aims to expand our understanding of these iron overload diseases and identify relationships between known NBIA genes and their main interacting partners by using a systems biology approach. We used whole-transcriptome gene expression data from human brain samples originating from 101 neuropathologically normal individuals (10 brain regions) to generate weighted gene co-expression networks and cluster the 10 known NBIA genes in an unsupervised manner. We investigated NBIA-enriched networks for relevant cell types and pathways, and whether they are disrupted by iron loading in NBIA diseased tissue and in an in vivo mouse model. We identified two basal ganglia gene co-expression modules significantly enriched for NBIA genes, which resemble neuronal and oligodendrocytic signatures. These NBIA gene networks are enriched for iron-related genes, and implicate synapse and lipid metabolism related pathways. Our data also indicates that these networks are disrupted by excessive brain iron loading. We identified multiple cell types in the origin of NBIA disorders. We also found unforeseen links between NBIA networks and iron-related processes, and demonstrate convergent pathways connecting NBIAs and phenotypically overlapping diseases. Our results are of further relevance for these diseases by providing candidates for new causative genes and possible points for therapeutic intervention. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Brain and retinal ferroportin 1 dysregulation in polycythaemia mice.

PubMed

Iacovelli, Jared; Mlodnicka, Agnieska E; Veldman, Peter; Ying, Gui-Shuang; Dunaief, Joshua L; Schumacher, Armin

2009-09-15

Disruption of iron homeostasis within the central nervous system (CNS) can lead to profound abnormalities during both development and aging in mammals. The radiation-induced polycythaemia (Pcm) mutation, a 58-bp microdeletion in the promoter region of ferroportin 1 (Fpn1), disrupts transcriptional and post-transcriptional regulation of this pivotal iron transporter. This regulatory mutation induces dynamic alterations in peripheral iron homeostasis such that newborn homozygous Pcm mice exhibit iron deficiency anemia with increased duodenal Fpn1 expression while adult homozygotes display decreased Fpn1 expression and anemia despite organismal iron overload. Herein we report the impact of the Pcm microdeletion on iron homeostasis in two compartments of the central nervous system: brain and retina. At birth, Pcm homozygotes show a marked decrease in brain iron content and reduced levels of Fpn1 expression. Upregulation of transferrin receptor 1 (TfR1) in brain microvasculature appears to mediate the compensatory iron uptake during postnatal development and iron content in Pcm brain is restored to wild-type levels by 7 weeks of age. Similarly, changes in expression are transient and expression of Fpn1 and TfR1 is indistinguishable between Pcm homozygotes and wild-type by 12 weeks of age. Strikingly, the adult Pcm brain is effectively protected from the peripheral iron overload and maintains normal iron content. In contrast to Fpn1 downregulation in perinatal brain, the retina of Pcm homozygotes reveals increased levels of Fpn1 expression. While retinal morphology appears normal at birth and during early postnatal development, adult Pcm mice demonstrate a marked, age-dependent loss of photoreceptors. This phenotype demonstrates the importance of iron homeostasis in retinal health.

lbtA and lbtB Are Required for Production of the Legionella pneumophila Siderophore Legiobactin

PubMed Central

Allard, Kimberly A.; Viswanathan, V. K.; Cianciotto, Nicholas P.

2006-01-01

Under iron stress, Legionella pneumophila secretes legiobactin, a nonclassical siderophore that is reactive in the chrome azurol S (CAS) assay. Here, we have optimized conditions for legiobactin expression, shown its biological activity, and identified two genes, lbtA and lbtB, which are involved in legiobactin production. lbtA appears to be iron repressed and encodes a protein that has significant homology with siderophore synthetases, and FrgA, a previously described iron-regulated protein of L. pneumophila. lbtB encodes a protein homologous with members of the major facilitator superfamily of multidrug efflux pumps. Mutants lacking lbtA or lbtB were defective for legiobactin, producing 40 to 70% less CAS reactivity in deferrated chemically defined medium (CDM). In bioassays, mutant CDM culture supernatants, unlike those of the wild type, did not support growth of iron-limited wild-type bacteria in 2′,2′-dipyridyl-containing buffered charcoal yeast extract (BCYE) agar and a ferrous iron transport mutant on BCYE agar without added iron. The lbtA mutant was modestly defective for growth in deferrated CDM containing the iron chelator citrate, indicating that legiobactin is required in conditions of severe iron limitation. Complementation of the lbt mutants restored both siderophore expression, as measured by the CAS assay and bioassays, and bacterial growth in deferrated, citrate-containing media. The lbtA mutant replicated as the wild type did in macrophages, amoebae, and the lungs of mice. However, L. pneumophila expresses lbtA in the macrophage, suggesting that legiobactin, though not required, may play a dispensable role in intracellular growth. The discovery of lbtAB represents the first identification of genes required for L. pneumophila siderophore expression. PMID:16452417

Dietary iron intake, iron status, and gestational diabetes.

PubMed

Zhang, Cuilin; Rawal, Shristi

2017-12-01

Pregnant women are particularly vulnerable to iron deficiency and related adverse pregnancy outcomes and, as such, are routinely recommended for iron supplementation. Emerging evidence from both animal and population-based studies, however, has raised potential concerns because significant associations have been observed between greater iron stores and disturbances in glucose metabolism, including increased risk of type 2 diabetes among nonpregnant individuals. Yet, the evidence is uncertain regarding the role of iron in the development of gestational diabetes mellitus (GDM), a common pregnancy complication which has short-term and long-term adverse health ramifications for both women and their children. In this review, we critically and systematically evaluate available data examining the risk of GDM associated with dietary iron, iron supplementation, and iron status as measured by blood concentrations of several indicators. We also discuss major methodologic concerns regarding the available epidemiologic studies on iron and GDM. © 2017 American Society for Nutrition.

Dropwise additive manufacturing of pharmaceutical products for amorphous and self emulsifying drug delivery systems.

PubMed

Içten, Elçin; Purohit, Hitesh S; Wallace, Chelsey; Giridhar, Arun; Taylor, Lynne S; Nagy, Zoltan K; Reklaitis, Gintaras V

2017-05-30

The improvements in healthcare systems and the advent of the precision medicine initiative have created the need to develop more innovative manufacturing methods for the delivery and production of individualized dosing and personalized treatments. In accordance with the changes observed in healthcare systems towards more innovative therapies, this paper presents dropwise additive manufacturing of pharmaceutical products (DAMPP) for small scale, distributed manufacturing of individualized dosing as an alternative to conventional manufacturing methods A dropwise additive manufacturing process for amorphous and self-emulsifying drug delivery systems is reported, which utilizes drop-on-demand printing technology for automated and controlled deposition of melt-based formulations onto inert tablets. The advantages of drop on demand technology include reproducible production of droplets with adjustable sizing and high placement accuracy, which enable production of individualized dosing even for low dose and high potency drugs. Flexible use of different formulations, such as lipid-based formulations, allows enhancement of the solubility of poorly water soluble and highly lipophilic drugs with DAMPP. Here, DAMPP is used to produce solid oral dosage forms from melts of an active pharmaceutical ingredient and a surfactant. The dosage forms are analyzed to show the amorphous nature, self-emulsifying drug delivery system characteristics and dissolution behavior of these formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioaccessibility and Cellular Uptake of β-Carotene Encapsulated in Model O/W Emulsions: Influence of Initial Droplet Size and Emulsifiers

PubMed Central

Kelly, Alan L.

2017-01-01

The effects of the initial emulsion structure (droplet size and emulsifier) on the properties of β-carotene-loaded emulsions and the bioavailability of β-carotene after passing through simulated gastrointestinal tract (GIT) digestion were investigated. Exposure to GIT significantly changed the droplet size, surface charge and composition of all emulsions, and these changes were dependent on their initial droplet size and the emulsifiers used. Whey protein isolate (WPI)-stabilized emulsion showed the highest β-carotene bioaccessibility, while sodium caseinate (SCN)-stabilized emulsion showed the highest cellular uptake of β-carotene. The bioavailability of emulsion-encapsulated β-carotene based on the results of bioaccessibility and cellular uptake showed the same order with the results of cellular uptake being SCN > TW80 > WPI. An inconsistency between the results of bioaccessibility and bioavailability was observed, indicating that the cellular uptake assay is necessary for a reliable evaluation of the bioavailability of emulsion-encapsulated compounds. The findings in this study contribute to a better understanding of the correlation between emulsion structure and the digestive fate of emulsion-encapsulated nutrients, which make it possible to achieve controlled or potential targeted delivery of nutrients by designing the structure of emulsion-based carriers. PMID:28930195

Development of a self-emulsifying formulation that reduces the food effect for torcetrapib.

PubMed

Perlman, M E; Murdande, S B; Gumkowski, M J; Shah, T S; Rodricks, C M; Thornton-Manning, J; Freel, D; Erhart, L C

2008-03-03

Torcetrapib is a highly lipophilic (Clog P=7.45) and water insoluble cholesteryl ester transfer protein (CETP) inhibitor developed for the treatment of atherosclerosis. Self-emulsifying drug delivery system (SEDDS) formulations have been developed to reduce the food effect observed in early clinical trials using medium chain triglyceride (MCT) softgels and to increase the dose per capsule. MCT/Triacetin/Polysorbate 80/Capmul MCM (20/30/20/30) (MTPC) increased fasted exposure and thus reduced the food effect from 5- to 3-fold in dogs at a dose of 90 mg. Self-emulsifying formulations also accelerated absorption and generally decreased variability. Use of the lipophilic, GRAS cosolvent triacetin allowed a 2-fold increase in the dose per capsule. For the three formulations evaluated in dogs that showed significant differences in absorption, emulsion droplet size did not appear to play a significant role. Absorption did increase with Cremophor RH40 content, and at 50% Cremophor RH40 there was no food effect (at 30 mg). High polar surfactant content also resulted in poor dose proportionality, while there was good dose proportionality for MTPC. Studies of in vitro lipolysis are being conducted to aid in understanding the in vitro/in vivo relationships for torcetrapib SEDDS absorption.

Production of coconut protein powder from coconut wet processing waste and its characterization.

PubMed

Naik, Aduja; Raghavendra, S N; Raghavarao, K S M S

2012-07-01

Virgin coconut oil (VCO) has been gaining popularity in recent times. During its production, byproducts such as coconut skim milk and insoluble protein are obtained which are underutilized or thrown away to the environment at present. This study deals with utilization of these byproducts to obtain a value-added product, namely, coconut protein powder. When coconut milk was subjected to centrifugation, three phases, namely, fat phase (coconut cream), aqueous phase (coconut skim milk), and solid phase (insoluble protein) were obtained. The coconut skim milk and insoluble protein were mixed and homogenized before spray drying to obtain a dehydrated protein powder. The proximate analysis of the powder showed high protein content (33 % w/w) and low fat content (3 % w/w). Protein solubility was studied as a function of pH and ionic content of solvent. Functional properties such as water hydration capacity, fat absorption capacity, emulsifying properties, wettability, and dispersibility of coconut protein powder were evaluated along with morphological characterization, polyphenol content, and color analysis. Coconut protein powder has shown to have good emulsifying properties and hence has potential to find applications in emulsified foods. Sensory analysis showed high overall quality of the product, indicating that coconut protein powder could be a useful food ingredient.

Effect of PLGA as a polymeric emulsifier on preparation of hydrophilic protein-loaded solid lipid nanoparticles.

PubMed

Xie, ShuYu; Wang, SiLiang; Zhao, BaoKai; Han, Chao; Wang, Ming; Zhou, WenZhong

2008-12-01

Most proteins are hydrophilic and poorly encapsulated into the hydrophobic matrix of solid lipid nanoparticles (SLN). To solve this problem, poly (lactic-co-glycolic acid) (PLGA) was utilized as a lipophilic polymeric emulsifier to prepare hydrophilic protein-loaded SLN by w/o/w double emulsion and solvent evaporation techniques. Hydrogenated castor oil (HCO) was used as a lipid matrix and bovine serum albumin (BSA), lysozyme and insulin were used as model proteins to investigate the effect of PLGA on the formulation of the SLN. The results showed that PLGA was essential for the primary w/o emulsification. In addition, the stability of the w/o emulsion, the encapsulation efficiency and loading capacity of the nanoparticles were enhanced with the increase of PLGA concentration. Furthermore, increasing PLGA concentration decreased zeta potential significantly but had no influence on particle size of the SLN. In vitro release study showed that PLGA significantly affected the initial burst release, i.e. the higher the content of PLGA, the lower the burst release. The released proteins maintained their integrity and bioactivity as confirmed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and biological assay. These results demonstrated that PLGA was an effective emulsifier for the preparation of hydrophilic protein-loaded SLN.

Joint Effects of Granule Size and Degree of Substitution on Octenylsuccinated Sweet Potato Starch Granules As Pickering Emulsion Stabilizers.

PubMed

Li, Jinfeng; Ye, Fayin; Lei, Lin; Zhou, Yun; Zhao, Guohua

2018-05-02

The granules of sweet potato starch were size fractionated into three portions with significantly different median diameters ( D 50 ) of 6.67 (small-sized), 11.54 (medium-sized), and 16.96 μm (large-sized), respectively. Each portion was hydrophobized at the mass-based degrees of substitution (DS m ) of approximately 0.0095 (low), 0.0160 (medium), and 0.0230 (high). The Pickering emulsion-stabilizing capacities of modified granules were tested, and the resultant emulsions were characterized. The joint effects of granule size and DS m on emulsifying capacity (EC) were investigated by response surface methodology. For small-, medium-, and large-sized fractions, their highest emulsifying capacities are comparable but, respectively, encountered at high (0.0225), medium (0.0158), and low (0.0095) DS m levels. The emulsion droplet size increased with granule size, and the number of freely scattered granules in emulsions decreased with DS m . In addition, the term of surface density of the octenyl succinic group (SD -OSG ) was first proposed for modified starch granules, and it was proved better than DS m in interpreting the emulsifying capacities of starch granules with varying sizes. The present results implied that, as the particulate stabilizers, the optimal DS m of modified starch granules is size specific.

Self-double-emulsifying drug delivery system (SDEDDS): a new way for oral delivery of drugs with high solubility and low permeability.

PubMed

Qi, Xiaole; Wang, Lishuang; Zhu, Jiabi; Hu, Zhenyi; Zhang, Jie

2011-05-16

Water-in-oil-in-water (w/o/w) double emulsions are potential for enhancing oral bioavailability of drugs with high solubility and low permeability, but their industrial application is limited due to the instability. Herein, we developed a novel formulation, self-double-emulsifying drug delivery systems (SDEDDS) by formulating mixtures of hydrophilic surfactants and water-in-oil (w/o) emulsions, which were easier to be stable through formulations optimization. SDEDDS can spontaneously emulsify to water-in-oil-in-water (w/o/w) double emulsions in the mixed aqueous gastrointestinal environment, with drugs encapsulated in the internal water phase of the double emulsions. We employed SDEDDS to improve the oral absorption of pidotimod, a peptide-like drug with high solubility and low permeability. The optimized pidotimod-SDEDDS were found to be stable up to 6 months under 25°C. Plasma concentration-time profiles from pharmacokinetic studies in rats dosed with SDEDDS showed 2.56-fold (p<0.05) increased absorption of pidotimod, compared to the pidotimod solution. Histopathologic studies confirmed that SDEDDS exerted absorption promoting effect without serious local damages. These studies demonstrate that SDEDDS may be a promising strategy for peroral delivery of peptide and peptidomimetic drugs. Copyright © 2011 Elsevier B.V. All rights reserved.

Emulsifying properties of acidic subunits of soy 11S globulin.

PubMed

Liu, M; Lee, D S; Damodaran, S

1999-12-01

The emulsifying properties of the acidic subunits (AS11S) isolated from soy glycinin (11S) have been studied. The isolated AS11S existed in solution mainly as a dimer species. Circular dichroic analysis indicated only a slight increase in aperiodic structure and no significant difference in beta-sheet structure when compared with those of soy 11S. At similar experimental conditions, the emulsifying properties of AS11S were superior to those of soy 11S and heat-denatured 11S. Emulsions prepared with 1% AS11S remained very stable without any visible oil separation for more than a month under gentle agitating conditions, whereas those prepared with 1% 11S collapsed and separated into phases within 2-3 days. The AS11S-stabilized emulsions were very stable below 0.15 M ionic strength. Studies on the rate of adsorption and surface tension reduction at the air-water interface showed that AS11S was significantly more surface active than soy 11S. It is proposed that, because the mass fraction of acidic subunits in soy 11S is approximately 60% and it is relatively easy to separate the acidic subunits from soy 11S, it may be industrially feasible to develop an economical process to isolate functional acidic subunits for use in emulsion-based food products.

Preparation and Evaluation of Multiple Nanoemulsions Containing Gadolinium (III) Chelate as a Potential Magnetic Resonance Imaging (MRI) Contrast Agent.

PubMed

Sigward, Estelle; Corvis, Yohann; Doan, Bich-Thuy; Kindsiko, Kadri; Seguin, Johanne; Scherman, Daniel; Brossard, Denis; Mignet, Nathalie; Espeau, Philippe; Crauste-Manciet, Sylvie

2015-09-01

The objective was to develop, characterize and assess the potentiality of W1/O/W2 self-emulsifying multiple nanoemulsions to enhance signal/noise ratio for Magnetic Resonance Imaging (MRI). For this purpose, a new formulation, was designed for encapsulation efficiency and stability. Various methods were used to characterize encapsulation efficiency ,in particular calorimetric methods (Differential Scanning Calorimetry (DSC), thermogravimetry analysis) and ultrafiltration. MRI in vitro relaxivities were assessed on loaded DTPA-Gd multiple nanoemulsions. Characterization of the formulation, in particular of encapsulation efficiency was a challenge due to interactions found with ultrafiltration method. Thanks to the specifically developed DSC protocol, we were able to confirm the formation of multiple nanoemulsions, differentiate loaded from unloaded nanoemulsions and measure the encapsulation efficiency which was found to be quite high with a 68% of drug loaded. Relaxivity studies showed that the self-emulsifying W/O/W nanoemulsions were positive contrast agents, exhibiting higher relaxivities than those of the DTPA-Gd solution taken as a reference. New self-emulsifying multiple nanoemulsions that were able to load satisfactory amounts of contrasting agent were successfully developed as potential MRI contrasting agents. A specific DSC protocol was needed to be developed to characterize these complex systems as it would be useful to develop these self-formation formulations.

Rapidly disintegrating vagina retentive cream suppositories of progesterone: development, patient satisfaction and in vitro/in vivo studies.

PubMed

Bendas, Ehab Rasmy; Basalious, Emad B

2016-01-01

Our objective was to develop novel vagina retentive cream suppositories (VRCS) of progesterone having rapid disintegration and good vaginal retention. VRCS of progesterone were prepared using oil in water (o/w) emulsion of mineral oil or theobroma oil in hard fat and compared with conventional vaginal suppositories (CVS) prepared by hard fat. VRCS formulations were tested for content uniformity, disintegration, melting range, in vitro release and stability studies. The most stable formulation (VRCS I) was subjected to scaling-up manufacturing and patients' satisfaction test. The rapid disintegration, good retentive properties are applicable through the inclusion of emulsified theobroma oil rather than hydrophilic surfactant into the hard fat bases. The release profile of progesterone from VRCS I showed a biphasic pattern due to the formation of progesterone reservoir in the emulsified theobroma oil. All volunteers involved in patients' satisfaction test showed high satisfactory response to the tested formulation (VRCS). The in vivo pharmacokinetic study suggests that VRCS of progesterone provided higher rate and extent of absorption compared to hard fat based suppositories. Our results proposed that emulsified theobroma oil could be promising to solve the problems of poor patients' satisfaction and variability of drug absorption associated with hard fat suppositories.

Development of rectal self-emulsifying suspension of a moisture-labile water-soluble drug.

PubMed

Kauss, Tina; Gaubert, Alexandra; Tabaran, Luc; Tonelli, Giovanni; Phoeung, Thida; Langlois, Marie-Hélène; White, Nick; Cartwright, Anthony; Gomes, Melba; Gaudin, Karen

2018-01-30

Self-emulsifying drug delivery systems, commonly used for oral delivery of poorly soluble compounds, were used to formulate water soluble but moisture labile compounds for rectal application. The objective was to use the oily phase of the system to formulate a liquid, non-aqueous product while obtaining the advantages of self-emulsification, rapid contact with the rectal mucosa and rapid absorption post-administration. Ceftriaxone was used as a model drug and the human bile salt sodium chenodeoxycholate was used as an absorption enhancer. After preliminary screening of 23 excipients, based on their emulsification ability and emulsion fineness in binary and ternary mixtures, a full factorial design was used to screen different formulations of three preselected excipients. The optimal formulation contained 60% of excipients, namely Capryol 90, Kolliphor EL and Kolliphor PS20 in 4 : 6 : 6 ratio and 40% of a powder blend that included 500 mg of ceftriaxone. Characterization of the system showed that it complied with the requirements for rectal administration, in particular rapid emulsification in a small quantity of liquid. Rabbit bioavailability showed rapid absorption of ceftriaxone, achieving 128% bioavailability compared to powder control formulation. These results demonstrated the potential of self-emulsifying formulations for rectal administration of Class 3 BCS drugs. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Scalable Method to Produce Biodegradable Nanoparticles that Rapidly Penetrate Human Mucus

PubMed Central

Xu, Qingguo; Boylan, Nicholas J.; Cai, Shutian; Miao, Bolong; Patel, Himatkumar; Hanes, Justin

2013-01-01

Mucus typically traps and rapidly removes foreign particles from the airways, gastrointestinal tract, nasopharynx, female reproductive tract and the surface of the eye. Nanoparticles capable of rapid penetration through mucus can potentially avoid rapid clearance, and open significant opportunities for controlled drug delivery at mucosal surfaces. Here, we report an industrially scalable emulsification method to produce biodegradable mucus-penetrating particles (MPP). The emulsification of diblock copolymers of poly(lactic-co-glycolic acid) and polyethylene glycol (PLGA-PEG) using low molecular weight (MW) emulsifiers forms dense brush PEG coatings on nanoparticles that allow rapid nanoparticle penetration through fresh undiluted human mucus. In comparison, conventional high MW emulsifiers, such as polyvinyl alcohol (PVA), interrupts the PEG coating on nanoparticles, resulting in their immobilization in mucus owing to adhesive interactions with mucus mesh elements. PLGA-PEG nanoparticles with a wide range of PEG MW (1, 2, 5, and 10 kDa), prepared by the emulsification method using low MW emulsifiers, all rapidly penetrated mucus. A range of drugs, from hydrophobic small molecules to hydrohilic large biologics, can be efficiently loaded into biodegradable MPP using the method described. This readily scalable method should facilitate the production of MPP products for mucosal drug delivery, as well as potentially longer-circulating particles following intravenous administration. PMID:23751567

A novel surfactant-free lipid-based formulation for improving oral bioavailability of loratadine using colloidal silicon dioxide as emulsifier and solid carrier.

PubMed

Huang, Ri; Tan, Yonggang; Shen, Lao; Wang, Tao; Quan, Dongqin

2018-05-08

The purpose of this study was to develop an innovative surfactant-free lipid-based formulation (LF) for improving oral bioavailability of loratadine based on using solid particles colloidal silicon dioxide (CSD) as emulsifier and solid carrier. Loratadine was dissolved in oil solution with the aid of co-solvent and LF were prepared by a simple adsorption and milling technique. The LF Powder was evaluated in terms of angle of repose and X-ray powder diffraction. After dispersing and emulsifying in water, the particle size and morphology were also characterized. In vitro dissolution and pharmacokinetic behavior in vivo were also studied. Orthogonal design indicated that the amount of CSD in formulations had a major and significant influence on emulsification. The optimal formulation showed LF with good flowability and without crystallization or deposition of loratadine in it. After dispersing in water, an emulsion with mean droplet size of 1.2μm was obtained. Although the dissolution of drug from LF was slower in vitro in acidic aqueous solution, pharmacokinetic studies in vivo showed that the bioavailability of loratadine increased 2.49-fold by CF compared to commercial tablet. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

PROTON GENERATION BY DISSOLUTION OF INTRINSIC OR AUGMENTED ALUMINOSILICATE MINERALS FOR IN SITU CONTAMINANT REMEDIATION BY ZERO-VALENCE-STATE IRON

EPA Science Inventory

Metallic, or zero-valence-state, iron is being incorporated into permeable reactive subsurface barriers for remediating a variety of contaminant plume types. The remediation occurs via reductive processes that are associated with surface corrosion of the iron metal. Reaction rate...

Iron deficiency anemia due to excessive green tea drinking.

PubMed

Fan, Frank S

2016-11-01

Tea interferes with iron absorption and can lead to iron deficiency anemia when consumed in large quantities. The rechallenge effect of green tea on anemia in a middle-aged man emphasizes the potential causal role of this beverage. Lifestyle and dietary habits are important diagnostic considerations in diseases of this type.

Developing a heme iron database for meats according to meat type, cooking method and doneness level

USDA-ARS?s Scientific Manuscript database

Background: Animal studies have demonstrated that iron may be related to carcinogenesis, and human studies found that heme iron can increase the formation of N-nitroso compounds, which are known carcinogens. Objectives: One of the postulated mechanisms linking red meat intake to cancer risk involves...

Lead-iron phosphate glass as a containment medium for the disposal of high-level nuclear wastes

DOEpatents

Boatner, L.A.; Sales, B.C.

1984-04-11

Disclosed are lead-iron phosphate glasses containing a high level of Fe/sub 2/O/sub 3/ for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste

Self-nanoemulsifying drug delivery system for enhanced bioavailability and improved hepatoprotective activity of biphenyl dimethyl dicarboxylate.

PubMed

El-Laithy, Hanan M

2008-07-01

Biphenyl Dimethyl Dicarboxylate (BDD) is insoluble in aqueous solution and the bioavailability after oral administration is low. Self-nanoemulsifying drug delivery system (SNEDDS) containing BDD has been successfully prepared using carefully selected ingredients which are less affected by pH and ionic strength changes to improve its bioavailability. SNEDDS is an isotropic mixture of lipid, surfactant, and cosurfactant which are spontaneously emulsified in aqueous medium under gentle digestive motility in the gastrointestinal tract. Pseudo ternary phase diagrams composed of various excipients were plotted to identify self -nano -emulsifying area. Droplet size changes upon dilution with aqueous media and in vitro release of BDD from SNEDDS in 0.1N HCl and phosphate buffer (pH 7.4) were studied and compared with commercial chinese pilules and Pennel capsules. The hepatoprotective activity upon oral administration of SNEDDS against carbon tetrachloride-induced oxidative stress in albino rats was assessed by measuring biochemical parameters like serum glutamic oxalacetate transaminase (SGOT), serum glutamic pyruvate transaminase (SGPT) and lactate dehydrogenase (LDH). Results showed that using a proper ratio of Tween 80 to Transcutol as surfactant and co-surfactant respectively and Miglyol 812 as oil to surfactants mixture resulted in production of infinitely diluted formulations in nano droplet size range. BDD self nano emulsified formula composed of 20% Miglyol 812, 60% Tween 80 and 20% Transcutol released 99% of the drug very rapidly within 10-15 minutes regardless of the pH condition. The oral absorption and bioavailability of BDD self nano emulsified formula in albino rats were significantly enhanced (P<0.01) with an average improvement of 1.7 and 6-folds that of commercial chinese pilules and Pennel capsules respectively. This improvement was also confirmed histopathologically in chemically injured rats and by the significant decrease in elevated liver enzymes level.

Variation in emulsion stabilization behavior of hybrid silicone polymers with change in molecular structure: Phase diagram study.

PubMed

Mehta, Somil C; Somasundaran, P; Kulkarni, Ravi

2009-05-15

Silicone oils are widely used in cosmetics and personal care applications to improve softness and condition skin and hair. Being insoluble in water and most hydrocarbons, a common mode of delivering them is in the form of emulsions. Currently most applications use polyoxyethylene (non-ionic) modified siloxanes as emulsifiers to stabilize silicone oil emulsions. However, ionically grafted silicone polymers have not received much attention. Ionic silicones have significantly different properties than the non-ionic counterpart. Thus considerable potential exists to formulate emulsions of silicones with different water/silicone oil ratios for novel applications. In order to understand the mechanisms underlying the effects of hydrophilic modifications on the ability of hybrid silicone polymers to stabilize various emulsions, this article focuses on the phase diagram studies for silicone emulsions. The emulsifying ability of functional silicones was seen to depend on a number of factors including hydrophilicity of the polymer, nature of the functional groups, the extent of modification, and the method of emulsification. It was observed that the region of stable emulsion in a phase diagram expanded with increase in shear rate. At a given shear rate, the region of stable emulsion and the nature of emulsion (water-in-oil or oil-in-water) was observed to depend on hydrophilic-hydrophobic balance of the hybrid silicone emulsifier. At a fixed amount of modification, the non-ionically modified silicone stabilized an oil-in-water emulsion, whereas the ionic silicones stabilized inverse water-in-oil emulsions. This was attributed to the greater hydrophilicity of the polyoxyethylene modified silicones than the ionic counterparts. In general, it is postulated that with progressive increase in hydrophilicity of hybrid silicone emulsifiers, their tendency to stabilize water-in-oil emulsion decreases with corresponding increase in oil-in-water emulsion. Further, this behavior is hypothesized to depend on the nature of modifying functional groups. Thus a hybrid silicone polymer can be tailored by selecting the nature and degree of hydrophilicity to obtain a desired silicone emulsion.

ESR studies on the influence of physiological dissolution and digestion media on the lipid phase characteristics of SEDDS and SEDDS pellets.

PubMed

Abdalla, Ahmed; Mäder, Karsten

2009-02-09

The aim of the current study is the evaluation of a recently optimized SEDDS, composed of Solutol HS15 and medium chain glycerides, and self-emulsifying pellets by means of ESR. Tempol-benzoate (TB)-loaded SEDDS were produced and electron spin resonance (ESR) spectroscopy was used to evaluate the diluted self-emulsifying mixtures. Moreover, ESR in vitro digestion experiments were carried out to have an insight on the characteristics of the different phases formed during the digestion process and to evaluate the distribution and the localization of TB in these phases. In addition, self-emulsifying pellets were produced using nitroxide-loaded SEDDS and the microenvironment within the pellets during release process was monitored in an online process using ESR spectroscopy. After dilution of nitroxide-loaded SEDDS, the percent of TB localized in the lipophilic compartment was decreasing with increasing the surfactant fraction in the mixture. Moreover, it was found that different phases with variable viscosity and polarity were produced as a result of the enzymatic digestion of SEDDS in physiologically relevant media. This change in lipid composition has largely affected the distribution and the localization of the spin probe during the digestion process. A rapid increase in the mobility of the spin probe inside the pellets was noticed after exposure to the release media. Additionally, TB was localized within the self-emulsifying mixture environment for the time of the experiment. ESR is considered a powerful non-invasive tool to assess the microenvironment of the diluted SEDDS and to monitor in vitro digestion process. Digestion induces a change in lipid composition which can affect the solubilization capacity of the administered drug. Therefore, monitoring in vitro digestion process using ESR spectroscopy will help in providing greater understanding of the interaction between the administered drug and the digested lipid vehicles.

Optimization of Manufacturing Conditions for Improving Storage Stability of Coffee-Supplemented Milk Beverage Using Response Surface Methodology.

PubMed

Ahn, Sung-Il; Park, Jun-Hong; Kim, Jae-Hoon; Oh, Duk-Geun; Kim, Moojoong; Chung, Donghwa; Jhoo, Jin-Woo; Kim, Gur-Yoo

2017-01-01

This study aimed at optimizing the manufacturing conditions of a milk beverage supplemented with coffee, and monitoring its physicochemical and sensory properties during storage. Raw milk, skim milk powder, coffee extract, and emulsifiers were used to manufacture the beverage. Two sucrose fatty acid esters, F110 and F160, were identified as suitable emulsifiers. The optimum conditions for the beverage manufacture, which can satisfy two conditions at the same time, determined by response surface methodology (RSM), were 5,000 rpm primary homogenization speed and 0.207% sucrose fatty acid emulsifier addition. The particle size and zeta-potential of the beverage under the optimum condition were 190.1 nm and - 25.94±0.06 mV, respectively. In comparison study between F110 added group (GF110) and F160 added group (GF160) during storage, all samples maintained its pH around 6.6 to 6.7, and there was no significant difference ( p <0.05). In addition, GF110 showed significantly higher zeta-potential than GF160 ( p <0.05). The particle size of GF110 and GF160 were approximately 190.1 and 223.1 nm, respectively at initial. However, size distribution of the GF160 tended to increase during storage. Moreover, increase of the particle size in GF160 was observed in microphotographs of it during storage. The L* values gradually decreased within all groups, whereas the a* and b* values did not show significant variations ( p <0.05). Compared with GF160, bitterness, floating cream, and rancid flavor were more pronounced in the GF110. Based on the result obtained from the present study, it appears that the sucrose fatty acid ester F110 is more suitable emulsifier when it comes to manufacturing this beverage than the F160, and also contributes to extending product shelf-life.

Optimization of Manufacturing Conditions for Improving Storage Stability of Coffee-Supplemented Milk Beverage Using Response Surface Methodology

PubMed Central

Kim, Jae-Hoon; Oh, Duk-Geun; Kim, Moojoong; Chung, Donghwa

2017-01-01

This study aimed at optimizing the manufacturing conditions of a milk beverage supplemented with coffee, and monitoring its physicochemical and sensory properties during storage. Raw milk, skim milk powder, coffee extract, and emulsifiers were used to manufacture the beverage. Two sucrose fatty acid esters, F110 and F160, were identified as suitable emulsifiers. The optimum conditions for the beverage manufacture, which can satisfy two conditions at the same time, determined by response surface methodology (RSM), were 5,000 rpm primary homogenization speed and 0.207% sucrose fatty acid emulsifier addition. The particle size and zeta-potential of the beverage under the optimum condition were 190.1 nm and - 25.94±0.06 mV, respectively. In comparison study between F110 added group (GF110) and F160 added group (GF160) during storage, all samples maintained its pH around 6.6 to 6.7, and there was no significant difference (p<0.05). In addition, GF110 showed significantly higher zeta-potential than GF160 (p<0.05). The particle size of GF110 and GF160 were approximately 190.1 and 223.1 nm, respectively at initial. However, size distribution of the GF160 tended to increase during storage. Moreover, increase of the particle size in GF160 was observed in microphotographs of it during storage. The L* values gradually decreased within all groups, whereas the a* and b* values did not show significant variations (p<0.05). Compared with GF160, bitterness, floating cream, and rancid flavor were more pronounced in the GF110. Based on the result obtained from the present study, it appears that the sucrose fatty acid ester F110 is more suitable emulsifier when it comes to manufacturing this beverage than the F160, and also contributes to extending product shelf-life. PMID:28316475

Iron Concentration in Deep Gray Matter Structures is Associated with Worse Visual Memory Performance in Healthy Young Adults

PubMed Central

Darnai, Gergely; Nagy, Szilvia Anett; Horváth, Réka; Ács, Péter; Perlaki, Gábor; Orsi, Gergely; Kovács, Norbert; Altbäcker, Anna; Plózer, Enikő; Tényi, Dalma; Weintraut, Rita; Schwarcz, Attila; John, Flóra; Varga, Eszter; Bereczkei, Tamás; Clemens, Zsófia; Komoly, Sámuel; Janszky, József

2017-01-01

Abnormally high deposition of iron can contribute to neurodegenerative disorders with cognitive impairment. Since previous studies investigating cognition-brain iron accumulation relationships focused on elderly people, our aim was to explore the association between iron concentration in subcortical nuclei and two types of memory performances in a healthy young population. Gender difference was found only in the globus pallidus. Our results showed that iron load characterized by R2* value on the MRI in the caudate and putamen was related to visual memory, while verbal memory was unrelated to iron concentration. PMID:28671115

Petrogenesis of Permian A-type granitoids in the Cihai iron ore district, Eastern Tianshan, NW China: Constraints on the timing of iron mineralization and implications for a non-plume tectonic setting

NASA Astrophysics Data System (ADS)

Zheng, Jiahao; Mao, Jingwen; Chai, Fengmei; Yang, Fuquan

2016-09-01

The geochronology and geochemistry of granitoids in the Eastern Tianshan, NW China provide important constraints on the timing of iron mineralization, as well as in understanding evolution history of the southern Central Asian Orogenic Belt (CAOB). Here we present results from a detailed study on granitoid rocks from the Cihai iron ore district in the Beishan region, southern part of the Eastern Tianshan. The granitoid rocks are composed of granodiorite, quartz monzonite, granite, and monzonite. Zircon U-Pb analyses yielded the ages of 294.1 ± 2.2 Ma, 286.5 ± 0.7 Ma, 284.3 ± 3.3 Ma, and 265.6 ± 3.0 Ma, respectively, suggesting they were formed in Early-Middle Permian. Among these granitoid rocks, the ages of quartz monzonite and granite are close to the timing of iron mineralization ( 282 Ma), indicating they may provide a source of iron in the Cihai ore district. Geochemically, the granodiorite, granite, and quartz monzonite samples are characterized by high FeOt/(FeOt + MgO) and Ga/Al ratios (0.84-0.94 and 2.28-3.27, respectively), as well as high zircon saturation temperatures (781-908 °C), similar to those of typical A-type granitoids. Isotopically, they display consistently depleted Hf isotopic compositions (εHf(t) = + 1.18 to + 15.37). Geological, geochemical, and isotopic data suggest that the Cihai A-type granitoids were derived from melting of juvenile lower crust. Some Early Permian A-type granitoids were recently identified in the Tarim and Eastern Tianshan with the ages between 294 and 269 Ma. The A-type granitoids in the Eastern Tianshan formed earlier between 294-284 Ma and exhibit characteristics of A2 type granitoids, whereas the A-type granitoids in the Tarim formed later between 277-269 Ma and show A1 granitoids affinity. We suggest that the Permian Tarim mantle plume does not account for the formation of the A-type granitoids in the Eastern Tianshan area, and the Eastern Tianshan was in a non-plume tectonic setting during Early Permian time. A slab break-off event has been suggested as the possible tectonic mechanism that triggered the formation of Early Permian A-type granitoids in the Eastern Tianshan.

Ordered iron aluminide alloys having an improved room-temperature ductility and method thereof

DOEpatents

Sikka, Vinod K.

1992-01-01

A process is disclosed for improving the room temperature ductility and strength of iron aluminide intermetallic alloys. The process involves thermomechanically working an iron aluminide alloy by means which produce an elongated grain structure. The worked alloy is then heated at a temperature in the range of about 650.degree. C. to about 800.degree. C. to produce a B2-type crystal structure. The alloy is rapidly cooled in a moisture free atmosphere to retain the B2-type crystal structure at room temperature, thus providing an alloy having improved room temperature ductility and strength.

Acceptability and use of iron and iron-alloy cooking pots: implications for anaemia control programmes.

PubMed

Tripp, Katherine; Mackeith, Nancy; Woodruff, Bradley A; Talley, Leisel; Mselle, Laurent; Mirghani, Zahra; Abdalla, Fathia; Bhatia, Rita; Seal, Andrew J

2010-01-01

To evaluate the acceptability of iron and iron-alloy cooking pots prior to an intervention trial and to investigate factors affecting retention and use. Pre-trial research was conducted on five types of iron and iron-alloy pots using focus group discussions and a laboratory evaluation of Fe transfer during cooking was undertaken. Usage and retention during the subsequent intervention trial were investigated using focus group discussions and market monitoring. Three refugee camps in western Tanzania. Refugee health workers were selected for pre-trial research. Mothers of children aged 6-59 months participated in the investigation of retention and use. Pre-trial research indicated that the stainless steel pot would be the only acceptable type for use in this population due to excessive rusting and/or the high weight of other types. Cooking three typical refugee dishes in stainless steel pots led to an increase in Fe content of 3.2 to 17.1 mg/100 g food (P < 0.001). During the trial, the acceptability of the stainless steel pots was lower than expected owing to difficulties with using, cleaning and their utility for other purposes. Households also continued to use their pre-existing pots, and stainless steel pots were sold to increase household income. Pre-trial research led to the selection of a stainless steel pot that met basic acceptability criteria. The relatively low usage reported during the trial highlights the limitations of using high-value iron-alloy cooking pots as an intervention in populations where poverty and the availability of other pots may lead to selling.

Iron overload causes osteoporosis in thalassemia major patients through interaction with transient receptor potential vanilloid type 1 (TRPV1) channels

PubMed Central

Rossi, Francesca; Perrotta, Silverio; Bellini, Giulia; Luongo, Livio; Tortora, Chiara; Siniscalco, Dario; Francese, Matteo; Torella, Marco; Nobili, Bruno; Di Marzo, Vincenzo; Maione, Sabatino

2014-01-01

The pathogenesis of bone resorption in β-thalassemia major is multifactorial and our understanding of the underlying molecular and cellular mechanisms remains incomplete. Considering the emerging importance of the endocannabinoid/endovanilloid system in bone metabolism, it may be instructive to examine a potential role for this system in the development of osteoporosis in patients with β-thalassemia major and its relationship with iron overload and iron chelation therapy. This study demonstrates that, in thalassemic-derived osteoclasts, tartrate-resistant acid phosphatase expression inversely correlates with femoral and lumbar bone mineral density, and directly correlates with ferritin levels and liver iron concentration. The vanilloid agonist resiniferatoxin dramatically reduces cathepsin K levels and osteoclast numbers in vitro, without affecting tartrate-resistant acid phosphatase expression. The iron chelators deferoxamine, deferiprone and deferasirox decrease both tartrate-resistant acid phosphatase and cathepsin K expression, as well as osteoclast activity. Taken together, these data show that transient receptor potential vanilloid type 1 activation/desensitization influences tartrate-resistant acid phosphatase expression and activity, and this effect is dependent on iron, suggesting a pivotal role for iron overload in the dysregulation of bone metabolism in patients with thalassemia major. Our applied pharmacology provides evidence for the potential of iron chelators to abrogate these effects by reducing osteoclast activity. Whether iron chelation therapy is capable of restoring bone health in humans requires further study, but the potential to provide dual benefits for patients with β-thalassemia major –preventing iron-overload and alleviating associated osteoporotic changes – is exciting. PMID:25216685

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchenko, A. V.; Terukov, E. I.; Egorova, A. Yu.

Impurity iron atoms in vitreous arsenic-selenide As{sub 2}Se{sub 3} films modified by iron form one-electron donor centers with an ionization energy of 0.24 (3) eV (the energy is counted from the conduction-band bottom). The Fermi level is shifted with an increase in the iron concentration from the mid-gap to the donorlevel position of iron due to the filling of one-electron states of the acceptor type lying below the Fermi level. At an iron concentration of ≥3 at %, the electron-exchange process is observed between neutral and ionized iron centers resulting in a change both in the electron density and inmore » the tensor of the electric-field gradient at iron-atom nuclei with increasing temperature above 350 K.« less

Hereditary hemochromatosis, iron, hepcidin, and coronary heart disease.

PubMed

Mascitelli, Luca; Goldstein, Mark R

2014-03-01

Mounting evidence suggests that a state of sustained iron depletion may exert a primary protective action against coronary heart disease. A persistent criticism of the iron hypothesis has been that atherosclerosis may not be a prominent feature of hereditary hemochromatosis. The essence of this criticism is that iron cannot be a significant factor in atherogenesis in those unaffected by inherited iron overload unless an increase in atherosclerosis is observed in hereditary hemochromatosis. However, the emerging details of the physiology of hepcidin, the key hormone in iron recycling, suggest a resolution of the apparent paradox of an important role for iron in atherogenesis in the possible absence of increased plaque burden in most types of hereditary hemochromatosis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sequence analysis of dolphin ferritin H and L subunits and possible iron-dependent translational control of dolphin ferritin gene

PubMed Central

Takaesu, Azusa; Watanabe, Kiyotaka; Takai, Shinji; Sasaki, Yukako; Orino, Koichi

2008-01-01

Background Iron-storage protein, ferritin plays a central role in iron metabolism. Ferritin has dual function to store iron and segregate iron for protection of iron-catalyzed reactive oxygen species. Tissue ferritin is composed of two kinds of subunits (H: heavy chain or heart-type subunit; L: light chain or liver-type subunit). Ferritin gene expression is controlled at translational level in iron-dependent manner or at transcriptional level in iron-independent manner. However, sequencing analysis of marine mammalian ferritin subunits has not yet been performed fully. The purpose of this study is to reveal cDNA-derived amino acid sequences of cetacean ferritin H and L subunits, and demonstrate the possibility of expression of these subunits, especially H subunit, by iron. Methods Sequence analyses of cetacean ferritin H and L subunits were performed by direct sequencing of polymerase chain reaction (PCR) fragments from cDNAs generated via reverse transcription-PCR of leukocyte total RNA prepared from blood samples of six different dolphin species (Pseudorca crassidens, Lagenorhynchus obliquidens, Grampus griseus, Globicephala macrorhynchus, Tursiops truncatus, and Delphinapterus leucas). The putative iron-responsive element sequence in the 5'-untranslated region of the six different dolphin species was revealed by direct sequencing of PCR fragments obtained using leukocyte genomic DNA. Results Dolphin H and L subunits consist of 182 and 174 amino acids, respectively, and amino acid sequence identities of ferritin subunits among these dolphins are highly conserved (H: 99–100%, (99→98) ; L: 98–100%). The conserved 28 bp IRE sequence was located -144 bp upstream from the initiation codon in the six different dolphin species. Conclusion These results indicate that six different dolphin species have conserved ferritin sequences, and suggest that these genes are iron-dependently expressed. PMID:18954429

Expression of Malus xiaojinensis IRT1 (MxIRT1) protein in transgenic yeast cells leads to degradation through autophagy in the presence of excessive iron.

PubMed

Li, Shuang; Zhang, Xi; Zhang, Xiu-Yue; Xiao, Wei; Berry, James O; Li, Peng; Jin, Si; Tan, Song; Zhang, Peng; Zhao, Wei-Zhong; Yin, Li-Ping

2015-07-01

Iron is essential for plants, but highly toxic when present in excess. Consequently, iron uptake by root transporters must be finely tuned to avoid excess uptake from soil under iron excess. The iron-regulated transporter of Malus xiaojinensis (MxIRT1), induced in roots under iron deficiency, is a highly effective iron(II) transporter. Here, we investigated how the presence of excessive iron leads to MxIRT1 degradation in yeast expressing this plant iron transporter protein. To determine the relationship between iron abundance and MxIRT1 degradation, relative levels of autophagy-related gene-8 (ATG8) mRNA and the active ATG8-phosphatidylethanolamine-conjugated (PE) protein were measured in wild-type yeast and the autophagic mutant strains atg1∆, atg5∆, atg7∆, ypt7∆ and tor1∆ under normal and excessive iron conditions. The data showed that the exposure of MxIRT1-eGFP-transformed wild-type and tor1∆ strains to excessive iron led to significantly increased levels of ATG8 transcript and ATG8-PE protein, which resulted in enhanced MxIRT1 degradation. Co-localization of mCherry-ATG8 and MxIRT1-eGFP provided evidence that these proteins interact during autophagy in yeast. While inhibition of autophagic initiation, autophagosome formation and vacuole fusion all decreased MxIRT1 degradation. PMSF inhibition of autophagy prevented degradation, leading to the accumulation of MxIRT1-containing vesicles in the vacuoles. MxIRT1-vesicles were sorted into autophagosomes for iron-induced degradation in yeast, whereas the endogenous iron(II) transporter Fet4 was degraded in an autophagy-independent manner. Moreover, immunoprecipitation showed that multimono-ubiquitins provided MxIRT1 with the ubiquitination signal. Together, three factors, iron excess, autophagy and mono-ubiquitination, affect the functional activity and stability of exogenous MxIRT1 in yeast, thereby preventing iron uptake via this root transporter. Copyright © 2015 John Wiley & Sons, Ltd.

Antifungal Activity of Diglycerin Ester of Fatty Acids against Yeasts and Its Comparison with Those of Sucrose Monopalmitate and Sodium Benzoate.

PubMed

Shimazaki, Aiko; Sakamoto, Jin J; Furuta, Masakazu; Tsuchido, Tetsuaki

2016-01-01

The antifungal activities of diglycerin monoester of fatty acids (DGCs), which have been employed as food emulsifiers, were examined against three yeasts, Saccharomyces cerevisiae, Candida albicans and Candida utilis and were compared with those of sucrose monoester of palmitic acid (SC16) as another type of emulsifier and sodium benzoate (SB) as a weak acid food preservative. When the minimum growth inhibitory concentrations (MICs) of diglycerin monolaurate (DGC12) against these yeasts were determined 2 d after incubation in YM broth at pH5.0, they were relatively low, being 0.01% (w/v), for both S. cerevisiae and C. utilis, whereas was high, being 4.0% (w/v), for C. albicans. On the contrary, the MICs of sucrose monopalmitate (SC16) were high, being 3.0 and 4.0% (w/v), for the former two yeasts, respectively, but 0.6% (w/v) for the last yeast. In contrast to these emulsifiers, the MICs of sodium benzoate (SB) were similar independently upon the yeast strain, being in order 0.4, 0.3 and 0.5% (w/v), for the above yeasts, respectively. The anti-yeast activities of DGC12 and SC16 were gradually increased with a decrease in pH, in a manner similar to that of SB, except for the action of SC16 on C. albicans, for which the activity was more effective at pHs 5.0 and 6.0 than at pHs 4.0 and 7.0. Among DGCs tested having different fatty acid moieties in the molecule, lauroyl ester (DGC12) was more effective than myristoyl and palmitoyl esters against S. cerevisiae and C. utilis. The inhibitory effect of DGC12 on the yeast growth depended upon both the cell density and the strength of aeration during the treatment. Further, DGC12 was found to kill S. cerevisiae and C. utilis cells at a rather low concentration of 0.005% (w/v) in 50mM acetate buffer at pH5.0, although, against C. albicans cells, only slight fungicidal activity was demonstrated at a high concentration of 0.5% (w/v). The results obtained support the effectiveness of practical application of DGC12 to acidic foods for the control of growth and survival of general yeasts such as S. cerevisiae and C. utilis.

Iron-mediated redox modulation in neural plasticity

PubMed Central

Muñoz, Pablo

2012-01-01

The role of iron in brain physiology has focused on the neuropathological, effects due to iron-induced oxidative stress. However, our recent work has established a physiological relationship between the iron-mediated oxidative modification and normal neuronal function. Our results obtained from hippocampal neurons, suggest that iron-generated reactive species oxygen (ROS) are involved in calcium signaling initiated by stimulation of NMDA receptors. This signal is amplified by ryanodine receptors (RyR), a redox- sensitive calcium channel, allowing the phosphorylation and nuclear translocation of ERK1/2. Furthermore, using electrophysiological approaches, we showed that iron is required for basal synaptic transmission and full expression of long-term potentiation, a type of synaptic plasticity. Our data combined suggest that the oxidative effect of iron is critical to activate processes that are downstream of NMDAR activation. Finally, due to the high reactivity of DNA with iron-generated ROS, we hypothesize an additional function of iron in gene regulation. PMID:22808323

Pathophysiology of Hereditary Hemochromatosis

PubMed Central

Fleming, Robert E.; Britton, Robert S.; Waheed, Abdul; Sly, William S.; Bacon, Bruce R.

2008-01-01

Hereditary hemochromatosis (HH) encompasses several inherited disorders of iron homeostasis characterized by increased gastrointestinal iron absorption and tissue iron deposition. The most common form of this disorder is HFE-related HH, nearly always caused by homozygosity for the C282Y mutation. A substantial proportion of C282Y homozygotes do not develop clinically significant iron overload, suggesting roles for environmental factors and modifier genes in determining the phenotype. Recent studies have demonstrated that the pathogenesis of nearly all forms of HH involves inappropriately decreased expression of the iron-regulatory hormone hepcidin. Hepcidin serves to decrease the export of iron from reticuloendothelial cells and absorptive enterocytes. Thus, HH patients demonstrate increased iron release from these cell types, elevated circulating iron, and iron deposition in vulnerable tissues. The mechanism by which HFE influences hepcidin expression is an area of current investigation and may offer insights into the phenotypic variability observed in persons with mutations in HFE. PMID:16315135

Absorption from iron tablets given with different types of meals.

PubMed

Hallberg, L; Björn-Rasmussen, E; Ekenved, G; Garby, L; Rossander, L; Pleehachinda, R; Suwanik, R; Arvidsson, B

1978-09-01

The absorption of iron from tablets given with 5 types of meals was studied in 153 subjects. The meals were: a hamburger meal with beans and potatoes, a simple breakfast meal, a Latin American meal composed of black beans, rice and maize and two Southeast Asian meals composed of rice, vegetables and spices served with and without fish. The groups were directly compared by relating the absorption from the iron tablets to the absorption from a standardized reference dose of iron given on an empty stomach. The composition of meals with respect to content of meat or fish or the presence of large amounts of phytates seemed to have no influence on the absorption of iron from tablets. The absorption from iron tablets was about 40% higher when they were given with rice meals than when they were given with the other meals studied. The average decrease in absorption by meals was about 50-60% based on a comparison when tablets were given on an empty stomach. When tablets from which the iron was released more slowly were used, the absorption increased by about 30% except when they were given with rice meals, where the absorption was unchanged. The differences among the meals in their effect on the absorption of iron from tablets thus disappeared when the slow-release tablets were given.

Legionella pneumophila mutants that are defective for iron acquisition and assimilation and intracellular infection.

PubMed Central

Pope, C D; O'Connell, W; Cianciotto, N P

1996-01-01

Legionella pneumophila, a parasite of macrophages and protozoa, requires iron for optimal extracellular and intracellular growth. However, its mechanisms of iron acquisition remain uncharacterized. Using mini-Tn10 mutagenesis, we isolated 17 unique L. pneumophila strains which appeared to be defective for iron acquisition and assimilation. Eleven of these mutants were both sensitive to the iron chelator ethylenediamine di(o-hydroxyphenylacetic acid) and resistant to streptonigrin, an antibiotic whose lethal effect requires high levels of intracellular iron. Six mutants were also defective for the infection of macrophage-like U937 cells. Although none were altered in entry, mutants generally exhibited prolonged lag phases and in some cases replicated at slower rates. Overall, the reduced recoveries of mutants, relative to that of the wild type, ranged from 3- to 1,000-fold. Strain NU216, the mutant displaying the most severe lag phase and the slowest rate of replication, was studied further. Importantly, within U937 cells, NU216 was approximately 100-fold more sensitive than the wild type was to treatment with the Fe3+ chelator deferoxamine, indicating that it is defective for intracellular iron acquisition and assimilation. Furthermore, this strain was unable to mediate any cytopathic effect and was impaired for infectivity of an amoebal host. Taken together, the isolation of these mutants offers genetic proof that iron acquisition and assimilation are critical for intracellular infection by L. pneumophila. PMID:8550218

Iron-depletion promotes mitophagy to maintain mitochondrial integrity in pathogenic yeast Candida glabrata

PubMed Central

Nagi, Minoru; Tanabe, Koichi; Nakayama, Hironobu; Ueno, Keigo; Yamagoe, Satoshi; Umeyama, Takashi; Ohno, Hideaki; Miyazaki, Yoshitsugu

2016-01-01

ABSTRACT Candida glabrata, a haploid budding yeast, is the cause of severe systemic infections in immune-compromised hosts. The amount of free iron supplied to C. glabrata cells during systemic infections is severely limited by iron-chelating proteins such as transferrin. Thus, the iron-deficiency response in C. glabrata cells is thought to play important roles in their survival inside the host's body. In this study, we found that mitophagy was induced under iron-depleted conditions, and that the disruption of a gene homologous to ATG32, which is responsible for mitophagy in Saccharomyces cerevisiae, blocked mitophagy in C. glabrata. The mitophagic activity in C. glabrata cells was not detected on short-period exposure to nitrogen-starved conditions, which is a mitophagy-inducing condition used in S. cerevisiae. The mitophagy-deficient atg32Δ mutant of C. glabrata also exhibited decreased longevity under iron-deficient conditions. The mitochondrial membrane potential in Cgatg32Δ cells was significantly lower than that in wild-type cells under iron-depleted conditions. In a mouse model of disseminated infection, the Cgatg32Δ strain resulted in significantly decreased kidney and spleen fungal burdens compared with the wild-type strain. These results indicate that mitophagy in C. glabrata occurs in an iron-poor host tissue environment, and it may contribute to the longevity of cells, mitochondrial quality control, and pathogenesis. PMID:27347716

The deposition of corrosion products in Pb17Li

NASA Astrophysics Data System (ADS)

Barker, Marten G.; Capaldi, Michael J.

1994-09-01

A series of simple deposition tests has been carried out in Pb17Li contained in type 316 stainless steel tubes under a temperature gradient. Two basic types of deposit have been identified from all 316 steel systems. The first type which is dendritic in form is composed mainly of iron and chromium and deposits in the temperature region 673 to 823 K. Deposits at the lower temperature were chromium rich whilst those at the higher temperature were iron-rich. The second type found at temperatures below 623 K shows a temperature dependence being composed of nickel and manganese at 573 K and nickel, iron and chromium at 623 K. Pure nickel only deposits if the alloy is at near saturation in nickel at the highest temperature of the system (873 K). Aluminium mass transfers readily in Pb17Li and in solution causes the formation of aluminide layers on the steel surface in the high temperature zone.

21 CFR 172.610 - Arabinogalactan.

Code of Federal Regulations, 2013 CFR

2013-04-01

... intended effect as an emulsifier, stabilizer, binder, or bodying agent: Essential oils, nonnutritive... food in accordance with the following conditions: (a) Arabinogalactan is a polysaccharide extracted by...

21 CFR 172.610 - Arabinogalactan.

Code of Federal Regulations, 2012 CFR

2012-04-01

... intended effect as an emulsifier, stabilizer, binder, or bodying agent: Essential oils, nonnutritive... food in accordance with the following conditions: (a) Arabinogalactan is a polysaccharide extracted by...

Properties of a bacterium which degrades solid poly(tetramethylene succinate)-co-adipate, a biodegradable plastic.

PubMed

Uchida, H; Nakajima-Kambe, T; Shigeno-Akutsu, Y; Nomura, N; Tokiwa, Y; Nakahara, T

2000-08-01

Various microorganisms were screened for their ability to degrade poly(tetramethylene succinate)-co-(tetramethylene adipate) (PBSA). Strain BS-3, which was newly isolated from a soil sample, was selected as the best strain. From taxonomical studies, the strain was tentatively ascribed to belong to the genus Acidovorax, most probably to the species A. delafieldii. Strain BS-3 could degrade both solid and emulsified PBSA, and also emulsified poly(tetramethylene succinate). During the degradation, a lipase activity was observed in the culture broth. This lipase activity was induced more strongly by PBSA than by tributyrin or triolein which are typical substrates of lipase. These observations strongly suggest that this lipase was involved in the PBSA biodegradation in strain BS-3.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diehl, J.F.; Adam, S.; Delincee, H.

Toxicological evaluation of irradiated foodstuffs requires knowledge of radiation-induced chemical changes. A review of the literature reveals much information on the radiation chemistry of pure substances, e.g., dilute solutions of individual carbohydrates. Much less is known about the interactions of food constituents during irradiation. In an effort to remedy this situation, radiation effects on various compounds have been studied in systems of increasing complexity. In one approach, gas chromatography was used to investigate the radiolysis of tehalose in pure solution and in the presence of amino acids or proteins. In another approach, radiation-induced aggregation of proteins and of (/sup 14/C)tryptophanmore » with proteins was studied in the absence and presence of carbohydrates (trehalose, starch), emulsified sunfower oil, and a mixture of carbohydrates and emulsified sunflower oil.« less

The effects of formulation on the immunostimulatory activity of dihydroheptaprenol.

PubMed

Roth, James A; Hibbard, Beth; Frank, Dagmar E; Kesl, Lyle; Robb, Edward J

2002-01-01

Holstein steer calves received a single injection of Miglyol (Sasol Chemical Industries, Ltd.) subcutaneously as a placebo, dihydroheptaprenol (DHP) (4 mg/kg) emulsified with lecithin subcutaneously, DHP in solution in Miglyol (4 mg/kg) subcutaneously, or DHP in solution in Miglyol (4 mg/kg) intranasally. The DHP emulsified in lecithin emulsion administered subcutaneously caused a substantial increase in body temperature, total leukocyte count, total neutrophil count, neutrophil cytochrome-c reduction, and neutrophil iodination 24 hours after administration and, for some of the parameters, at 48 hours. The DHP formulation in Miglyol did not have any of these effects when administered subcutaneously or intranasally. The carrier and formulation of DHP apparently have major effects on the biologic activity of DHP.

In vivo postprandial bioavailability of interesterified-lipids in sodium-caseinate or chitosan based O/W emulsions.

PubMed

Farfán, M; Villalón, M J; Ortíz, M E; Nieto, S; Bouchon, P

2015-03-15

Recent studies have shown that it should be possible to control lipid bioavailability through food structural approaches. Nevertheless, the gastrointestinal-tract physiological conditions must also be considered. To get a better understanding of this phenomenon, we evaluated the effect of emulsification, as well as the use of sodium caseinate or chitosan, on the postprandial bioavailability of interesterified-lipids in O/W emulsions after oral gastric feeding Sprague-Dawley rats. We verified that emulsification may increase lipid absorption, as determined after feeding sodium-caseinate emulsions. However, this result could not be generalised. Interesterified-lipids that were emulsified with chitosan were equally absorbed as those contained in non-emulsified interesterified-lipids/distilled-water blends. Copyright © 2014. Published by Elsevier Ltd.

THE EFFECT OF PH, PHOSPHATE AND OXIDANT TYPE ON THE REMOVAL OF ARSENIC FROM DRINKING WATER DURING IRON REMOVAL

EPA Science Inventory

In many regions of the United States, groundwaters that contain arsenic (primarily As[III]) also contain significant amounts of iron (Fe[II]). Arsenic removal will most likely be achieved by iron removal in many of those cases which will consist of oxidization followed by filtra...

Higher iron pearl millet (Pennisetum glaucum L.) provides more absorbable iron that is limited by increased polyphenolic content

USDA-ARS?s Scientific Manuscript database

Background: Our objective was to compare the capacity of iron (Fe) biofortified and standard pearl millet (Pennisetum glaucum L.) to deliver Fe for hemoglobin (Hb) synthesis. Pearl millet is the most widely grown type of millet. It is common primarily in West Africa and the Indian subcontinent, and ...

SYNTHESIS, REACTIVITY, AND CATALYTIC BEHAVIOR OF IRON/ZINC-CONTAINING SPECIES INVOLVED IN OXIDATION OF HYDROCARBONS UNDER GIF-TYPE CONDITIONS. (R823377)

EPA Science Inventory

The present study explores the nature and reactivity of iron- and zinc-containing species
generated in hydrocarbon-oxidizing Gif(IV)-type solutions Fe catalyst/Zn/O-2 in pyridine/acetic acid
(10:1 v/v). The ultimate goal of this investigation is to unravel the role of metal...

Medicago truncatula natural resistance-associated macrophage Protein1 is required for iron uptake by rhizobia-infected nodule cells.

PubMed

Tejada-Jiménez, Manuel; Castro-Rodríguez, Rosario; Kryvoruchko, Igor; Lucas, M Mercedes; Udvardi, Michael; Imperial, Juan; González-Guerrero, Manuel

2015-05-01

Iron is critical for symbiotic nitrogen fixation (SNF) as a key component of multiple ferroproteins involved in this biological process. In the model legume Medicago truncatula, iron is delivered by the vasculature to the infection/maturation zone (zone II) of the nodule, where it is released to the apoplast. From there, plasma membrane iron transporters move it into rhizobia-containing cells, where iron is used as the cofactor of multiple plant and rhizobial proteins (e.g. plant leghemoglobin and bacterial nitrogenase). MtNramp1 (Medtr3g088460) is the M. truncatula Natural Resistance-Associated Macrophage Protein family member, with the highest expression levels in roots and nodules. Immunolocalization studies indicate that MtNramp1 is mainly targeted to the plasma membrane. A loss-of-function nramp1 mutant exhibited reduced growth compared with the wild type under symbiotic conditions, but not when fertilized with mineral nitrogen. Nitrogenase activity was low in the mutant, whereas exogenous iron and expression of wild-type MtNramp1 in mutant nodules increased nitrogen fixation to normal levels. These data are consistent with a model in which MtNramp1 is the main transporter responsible for apoplastic iron uptake by rhizobia-infected cells in zone II. © 2015 American Society of Plant Biologists. All Rights Reserved.

Iron Oxide as an MRI Contrast Agent for Cell Tracking

PubMed Central

Korchinski, Daniel J.; Taha, May; Yang, Runze; Nathoo, Nabeela; Dunn, Jeff F.

2015-01-01

Iron oxide contrast agents have been combined with magnetic resonance imaging for cell tracking. In this review, we discuss coating properties and provide an overview of ex vivo and in vivo labeling of different cell types, including stem cells, red blood cells, and monocytes/macrophages. Furthermore, we provide examples of applications of cell tracking with iron contrast agents in stroke, multiple sclerosis, cancer, arteriovenous malformations, and aortic and cerebral aneurysms. Attempts at quantifying iron oxide concentrations and other vascular properties are examined. We advise on designing studies using iron contrast agents including methods for validation. PMID:26483609

Involvement of the mitogen activated protein kinase Hog1p in the response of Candida albicans to iron availability

PubMed Central

2013-01-01

Background Iron is an essential nutrient for almost all organisms, and generating iron limiting conditions for pathogens is one of the host defense strategies against microbial infections. Excess of iron can be toxic; therefore, iron uptake is tightly controlled. The high affinity iron uptake system of the opportunistic pathogenic yeast Candida albicans has been shown to be essential for virulence. Several transcription factors and regulators of iron uptake genes were identified, but the knowledge of signaling pathways is still limited. Gene expression profiling of the Δhog1 deletion mutant indicated an involvement of the mitogen activated protein (MAP) kinase Hog1p. However, the function of Hog1p in the response of C. albicans to iron availability was not studied in detail. Thus, we analyzed phenotypic and molecular responses of C. albicans to different iron concentrations particularly with respect to the activity of the Hog1p MAP kinase module. Results We observed flocculation of yeast cells, when the iron ion concentration was equal to or higher than 5 μM. This phenotype was dependent on the MAP kinase Hog1p and the corresponding MAP kinase kinase Pbs2p. Moreover, high extracellular iron ion concentrations led to hyper-phosphorylation of Hog1p. We determined lower amounts of multicopper ferroxidase (MCFO) proteins and lower ferric reductase activity, when the iron ion concentration in the medium was increased. This effect was also observed for the Δhog1 mutant. However, the amounts of MCFO proteins and the cell surface ferric reductase activity were increased in the Δhog1 in comparison to wild type cells. This effect was independent of iron availability in growth media. Conclusions In C. albicans, the MAP kinase Hog1p is part of the network regulating the response of the organism to iron availability. Hog1p was transiently phosphorylated under high iron concentrations and was essential for a flocculent phenotype. Furthermore, deletion of HOG1 led to increased levels of components of the reductive iron uptake system in comparison to the wild-type, independent of iron concentrations in the media. However, the additional induction of this system by low iron concentrations was independent of HOG1. PMID:23347662

Dysregulation of iron and copper homeostasis in nonalcoholic fatty liver

PubMed Central

Aigner, Elmar; Weiss, Günter; Datz, Christian

2015-01-01

Elevated iron stores as indicated by hyperferritinemia with normal or mildly elevated transferrin saturation and mostly mild hepatic iron deposition are a characteristic finding in subjects with non-alcoholic fatty liver disease (NAFLD). Excess iron is observed in approximately one third of NAFLD patients and is commonly referred to as the “dysmetabolic iron overload syndrome”. Clinical evidence suggests that elevated body iron stores aggravate the clinical course of NAFLD with regard to liver-related and extrahepatic disease complications which relates to the fact that excess iron catalyses the formation of toxic hydroxyl-radicals subsequently resulting in cellular damage. Iron removal improves insulin sensitivity, delays the onset of type 2 diabetes mellitus, improves pathologic liver function tests and likewise ameliorates NAFLD histology. Several mechanisms contribute to pathologic iron accumulation in NAFLD. These include impaired iron export from hepatocytes and mesenchymal Kupffer cells as a consequence of imbalances in the concentrations of iron regulatory factors, such as hepcidin, cytokines, copper or other dietary factors. This review summarizes the knowledge about iron homeostasis in NAFLD and the rationale for its therapeutic implications. PMID:25729473

Iron restriction and the growth of Salmonella enteritidis.

PubMed Central

Chart, H.; Rowe, B.

1993-01-01

Strains of Salmonella enteritidis were examined for their ability to remove ferric-ions from the iron chelating agents ovotransferrin, Desferal and EDDA. Growth of S. enteritidis phage type (PT) 4 (SE4) in trypticase soy broth containing ovotransferrin resulted in the expression of iron regulated outer membrane proteins (OMPs) of 74, 78 and 81 kDa, and unexpectedly the repression of expression of OMP C. The 38 MDa 'mouse virulence' plasmid was not required for the expression of the iron-regulated OMPs (IROMPs). SE4 was able to obtain iron bound to the iron chelator Desferal and EDDA without expressing a high-affinity iron uptake system. Strains of S. enteritidis belonging to PTs 7, 8, 13a, 23, 24 and 30 were also able to remove ferric ions from Desferal and EDDA without expressing a high-affinity iron uptake system. We conclude that strains of SE4 possess a high-affinity iron sequestering mechanism that can readily remove iron from ovotransferrin. It is likely that iron limitation, and not iron restriction, is responsible for the bacteriostatic properties of fresh egg whites. Images Fig. 2 PMID:8432322

21 CFR 131.149 - Dry cream.

Code of Federal Regulations, 2014 CFR

2014-04-01

...: (1) Emulsifiers. (2) Stabilizers. (3) Anticaking agents. (4) Antioxidants. (5) Nutritive carbohydrate... “sweetened” if no characterizing flavoring ingredients are used but nutritive carbohydrate sweetener is added...

Environmental Effects on the Metallicities of Early-Type Galaxies

NASA Technical Reports Server (NTRS)

Jones, Christine; Oliversen, Ronald (Technical Monitor)

2004-01-01

We completed and published two papers in the Astrophysical Journal based on research from grant. In the first paper we analyzed nine X-ray-bright Virgo early-type galaxies observed by both ASCA and ROSAT. Through spatially resolved spectroscopy, we determined the radial temperature profiles and abundances of Mg, Si, and Fe for six galaxies. The temperature profiles are consistent with isothermal temperatures outside of cooler regions at the galaxies' centers. We present new evidence for iron abundance gradients in NGC 4472 and NGC 4649 and confirm the previous results on NGC 4636. Mg and Si abundance gradients on average are flatter than those of iron and correspond to an underabundance of α-process elements at high Fe values, while at low iron the element ratios favor enrichment by Type II supernovae (SNe). We explain the observed trend using the metallicity dependence of SN Ia metal production and present constraints on the available theoretical modeling for low-metallicity inhibition of SNe Ia. In the second paper We analyzed nine X-ray-bright Virgo early-type galaxies observed by both ASCA and ROSAT. Through spatially resolved spectroscopy, we determined the radial temperature profiles and abundances of Mg, Si, and Fe for six galaxies. The temperature profiles are consistent with isothermal temperatures outside of cooler regions at the galaxies' centers. We present new evidence for iron abundance gradients in NGC 4472 and NGC 4649 and confirm the previous results on NGC 4636. Mg and Si abundance gradients on average are flatter than those of iron and correspond to an underabundance of α-process elements at high Fe values, while at low iron the element ratios favor enrichment by Type I1 supernovae (SNe). We explain the observed trend using the metallicity dependence of SN Ia metal production and present constraints on the available theoretical modeling for low-metallicity inhibition of SNe Ia.

Increased Retinal Expression of the Pro-Angiogenic Receptor GPR91 via BMP6 in a Mouse Model of Juvenile Hemochromatosis

PubMed Central

Arjunan, Pachiappan; Gnanaprakasam, Jaya P.; Ananth, Sudha; Romej, Michelle A.; Rajalakshmi, Veeranan-Karmegam; Prasad, Puttur D.; Martin, Pamela M.; Gurusamy, Mariappan; Thangaraju, Muthusamy; Bhutia, Yangzom D.; Ganapathy, Vadivel

2016-01-01

Purpose Hemochromatosis, an iron-overload disease, occurs as adult and juvenile types. Mutations in hemojuvelin (HJV), an iron-regulatory protein and a bone morphogenetic protein (BMP) coreceptor, underlie most of the juvenile type. Hjv−/− mice accumulate excess iron in retina and exhibit aberrant vascularization and angiomas. A succinate receptor, GPR91, is pro-angiogenic in retina. We hypothesized that Hjv−/− retinas have increased BMP signaling and increased GPR91 expression as the basis of angiomas. Methods Expression of GPR91 was examined by qPCR, immunofluorescence, and Western blot in wild-type and Hjv−/− mouse retinas and pRPE cells. Influence of excess iron and BMP6 on GPR91 expression was investigated in ARPE-19 cells, and wild-type and Hjv−/− pRPE cells. Succinate was used to activate GPR91 and determine the effects of GPR91 signaling on VEGF expression. Signaling of BMP6 was studied by the expression of Smad1/5/8 and pSmad4, and the BMP-target gene Id1. The interaction of pSmad4 with GPR91 promoter was studied by ChIP. Results Expression of GPR91 was higher in Hjv−/− retinas and RPE than in wild-type counterparts. Unexpectedly, BMP signaling was increased, not decreased, in Hjv−/− retinas and RPE. Bone morphogenetic protein 6 induced GPR91 in RPE, suggesting that increased BMP signaling in Hjv−/− retinas was likely responsible for GPR91 upregulation. Exposure of RPE to excess iron and succinate as well as BMP6 and succinate increased VEGF expression. Bone morphogenetic protein 6 promoted the interaction of pSmad4 with GPR91 promoter in RPE. Conclusions G-protein-coupled receptor 91 is a BMP6 target and Hjv deletion enhances BMP signaling in retina, thus underscoring a role for excess iron and hemochromatosis in abnormal retinal vascularization. PMID:27046124

Increased Retinal Expression of the Pro-Angiogenic Receptor GPR91 via BMP6 in a Mouse Model of Juvenile Hemochromatosis.

PubMed

Arjunan, Pachiappan; Gnanaprakasam, Jaya P; Ananth, Sudha; Romej, Michelle A; Rajalakshmi, Veeranan-Karmegam; Prasad, Puttur D; Martin, Pamela M; Gurusamy, Mariappan; Thangaraju, Muthusamy; Bhutia, Yangzom D; Ganapathy, Vadivel

2016-04-01

Hemochromatosis, an iron-overload disease, occurs as adult and juvenile types. Mutations in hemojuvelin (HJV), an iron-regulatory protein and a bone morphogenetic protein (BMP) coreceptor, underlie most of the juvenile type. Hjv(-/-) mice accumulate excess iron in retina and exhibit aberrant vascularization and angiomas. A succinate receptor, GPR91, is pro-angiogenic in retina. We hypothesized that Hjv(-/-) retinas have increased BMP signaling and increased GPR91 expression as the basis of angiomas. Expression of GPR91 was examined by qPCR, immunofluorescence, and Western blot in wild-type and Hjv(-/-) mouse retinas and pRPE cells. Influence of excess iron and BMP6 on GPR91 expression was investigated in ARPE-19 cells, and wild-type and Hjv(-/-) pRPE cells. Succinate was used to activate GPR91 and determine the effects of GPR91 signaling on VEGF expression. Signaling of BMP6 was studied by the expression of Smad1/5/8 and pSmad4, and the BMP-target gene Id1. The interaction of pSmad4 with GPR91 promoter was studied by ChIP. Expression of GPR91 was higher in Hjv(-/-) retinas and RPE than in wild-type counterparts. Unexpectedly, BMP signaling was increased, not decreased, in Hjv(-/-) retinas and RPE. Bone morphogenetic protein 6 induced GPR91 in RPE, suggesting that increased BMP signaling in Hjv(-/-) retinas was likely responsible for GPR91 upregulation. Exposure of RPE to excess iron and succinate as well as BMP6 and succinate increased VEGF expression. Bone morphogenetic protein 6 promoted the interaction of pSmad4 with GPR91 promoter in RPE. G-protein-coupled receptor 91 is a BMP6 target and Hjv deletion enhances BMP signaling in retina, thus underscoring a role for excess iron and hemochromatosis in abnormal retinal vascularization.

An overview of methods for assessment of iron bioavailability from foods nutritionally enhanced through biotechnology.

PubMed

Cockell, Kevin A

2007-01-01

Iron deficiency and iron deficiency anemia continue to be significant public health problems worldwide. While supplementation and fortification have been viable means to improve iron nutriture of the population in developed countries, they may be less successful in developing regions for a number of reasons, including complexities in distribution and consumer compliance. Biofortification of staple crops, through conventional plant breeding strategies or modern methods of biotechnology, provides an alternative approach that may be more sustainable once initial investments have been made. Three types of biofortification strategies are being essayed, singly or in combination: increasing the total iron content of edible portions of the plant, decreasing the levels of inhibitors of iron absorption, and increasing the levels of factors that enhance iron absorption. Bioavailability is a key concept in iron nutrition, particularly for nonheme iron such as is found in these biofortified foods. An overview is presented of methods for evaluation of iron bioavailability from foods nutritionally enhanced through biotechnology.

Alginate-Iron Speciation and Its Effect on In Vitro Cellular Iron Metabolism

PubMed Central

Horniblow, Richard D.; Dowle, Miriam; Iqbal, Tariq H.; Latunde-Dada, Gladys O.; Palmer, Richard E.

2015-01-01

Alginates are a class of biopolymers with known iron binding properties which are routinely used in the fabrication of iron-oxide nanoparticles. In addition, alginates have been implicated in influencing human iron absorption. However, the synthesis of iron oxide nanoparticles employs non-physiological pH conditions and whether nanoparticle formation in vivo is responsible for influencing cellular iron metabolism is unclear. Thus the aims of this study were to determine how alginate and iron interact at gastric-comparable pH conditions and how this influences iron metabolism. Employing a range of spectroscopic techniques under physiological conditions alginate-iron complexation was confirmed and, in conjunction with aberration corrected scanning transmission electron microscopy, nanoparticles were observed. The results infer a nucleation-type model of iron binding whereby alginate is templating the condensation of iron-hydroxide complexes to form iron oxide centred nanoparticles. The interaction of alginate and iron at a cellular level was found to decrease cellular iron acquisition by 37% (p < 0.05) and in combination with confocal microscopy the alginate inhibits cellular iron transport through extracellular iron chelation with the resulting complexes not internalised. These results infer alginate as being useful in the chelation of excess iron, especially in the context of inflammatory bowel disease and colorectal cancer where excess unabsorbed luminal iron is thought to be a driver of disease. PMID:26378798

Banded iron-formations of late Proterozoic age in the central eastern desert, Egypt: geology and tectonic setting.

USGS Publications Warehouse

Sims, P.K.; James, H.L.

1984-01-01

Iron-formation occurs as stratigraphic units within a layered andesite-basalt sequence. The sequence is metamorphosed to greenschist facies, intruded by syntectonic granodiorite and post-tectonic granite, and complexly deformed and grossly fragmented; the rocks are allochthonous along thrust faults. The iron deposits are chemical precipitates, accumulated during lulls in volcanism, apparently in an intraoceanic island-arc environment. The deposits are of the Algoma type of iron-formation.-G.J.N.

Hemochromatosis

MedlinePlus

Hemochromatosis is a disease in which too much iron builds up in your body. Your body needs iron but too much of it ... types of hemochromatosis. Primary hemochromatosis is an inherited disease. Secondary hemochromatosis is usually the result of something ...

Non-HFE haemochromatosis

PubMed Central

Wallace, Daniel F; Subramaniam, V Nathan

2007-01-01

Non-HFE hereditary haemochromatosis (HH) refers to a genetically heterogeneous group of iron overload disorders that are unlinked to mutations in the HFE gene. The four main types of non-HFE HH are caused by mutations in the hemojuvelin, hepcidin, transferrin receptor 2 and ferroportin genes. Juvenile haemochromatosis is an autosomal recessive disorder and can be caused by mutations in either hemojuvelin or hepcidin. An adult onset form of HH similar to HFE-HH is caused by homozygosity for mutations in transferrin receptor 2. The autosomal dominant iron overload disorder ferroportin disease is caused by mutations in the iron exporter ferroportin. The clinical characteristics and molecular basis of the various types of non-HFE haemochromatosis are reviewed. The study of these disorders and the molecules involved has been invaluable in improving our understanding of the mechanisms involved in the regulation of iron metabolism. PMID:17729390

Hypoxia-Inducible Factors Link Iron Homeostasis and Erythropoiesis

PubMed Central

Shah, Yatrik M.; Xie, Liwei

2014-01-01

Iron is required for efficient oxygen transport, and hypoxia signaling links erythropoiesis with iron homeostasis. Hypoxia induces a highly conserved signaling pathway in cells under conditions of low O2. One component of this pathway, hypoxia-inducible factor (HIF), is a transcription factor that is highly active in hypoxic cells. The first HIF target gene characterized was EPO, which encodes erythropoietin—a glycoprotein hormone that controls erythropoiesis. The past decade has led to fundamental advances in our understanding of how hypoxia regulates iron levels to support erythropoiesis and maintain systemic iron homeostasis. We review the cell-type specific effects of hypoxia and HIFs in adaptive response to changes in oxygen and iron availability, as well as potential uses of HIF modulators for patients with iron-related disorders. PMID:24389303

Anemia of Chronic Disease and Iron Deficiency Anemia in Inflammatory Bowel Diseases: Pathophysiology, Diagnosis, and Treatment.

PubMed

Murawska, Natalia; Fabisiak, Adam; Fichna, Jakub

2016-05-01

Anemia coexists with inflammatory bowel disease (IBD) in up to two-thirds of patients, significantly impairing quality of life. The most common types of anemia in patients with IBD are iron deficiency anemia and anemia of chronic disease, which often overlap. In most cases, available laboratory tests allow successful diagnosis of iron deficiency, where difficulties appear, recently established indices such as soluble transferrin-ferritin ratio or percentage of hypochromic red cells are used. In this review, we discuss the management of the most common types of anemia in respect of the latest available data. Thus, we provide the mechanisms underlying pathophysiology of these entities; furthermore, we discuss the role of hepcidin in developing anemia in IBD. Next, we present the treatment options for each type of anemia and highlight the importance of individual choice of action. We also focus on newly developed intravenous iron preparations and novel, promising drug candidates targeting hepcidin. Concurrently, we talk about difficulties in differentiating between the true and functional iron deficiency, and discuss tools facilitating the process. Finally, we emphasize the importance of proper diagnosis and treatment of anemia in IBD. We conclude that management of anemia in patients with IBD is tricky, and appropriate screening of patients regarding anemia is substantial.

Orbital-selective pairing and superconductivity in iron selenides

NASA Astrophysics Data System (ADS)

Nica, Emilian M.; Yu, Rong; Si, Qimiao

2017-12-01

An important challenge in condensed matter physics is understanding iron-based superconductors. Among these systems, the iron selenides hold the record for highest superconducting transition temperature and pose especially striking puzzles regarding the nature of superconductivity. The pairing state of the alkaline iron selenides appears to be of d-wave type based on the observation of a resonance mode in neutron scattering, while it seems to be of s-wave type from the nodeless gaps observed everywhere on the Fermi surface. Here we propose an orbital-selective pairing state, dubbed sτ3, as a natural explanation of these disparate properties. The pairing function, containing a matrix τ3 in the basis of 3d-electron orbitals, does not commute with the kinetic part of the Hamiltonian. This dictates the existence of both intraband and interband pairing terms in the band basis. A spin resonance arises from a d-wave-type sign change in the intraband pairing component, whereas the quasiparticle excitation is fully gapped on the FS due to an s-wave-like form factor associated with the addition in quadrature of the intraband and interband pairing terms. We demonstrate that this pairing state is energetically favored when the electron correlation effects are orbitally selective. More generally, our results illustrate how the multiband nature of correlated electrons affords unusual types of superconducting states, thereby shedding new light not only on the iron-based materials but also on a broad range of other unconventional superconductors such as heavy fermion and organic systems.

Retail colour stability of lamb meat is influenced by breed type, muscle, packaging and iron concentration.

PubMed

Warner, R D; Kearney, G; Hopkins, D L; Jacob, R H

2017-07-01

The longissmus lumborum (LL) and semimembranosus (SM) muscles from 391 lamb carcasses, derived from various breed types, were used to investigate the effect of animal/muscle factors, packaging type [over-wrap (OW) or high oxygen modified atmosphere packaging (MAP O2 )] and duration of display on redness of meat during simulated retail display. Using statistical models the time required (in days) for redness to reach a threshold value of 3.5 (below this is unacceptable) was predicted. High levels of iron in the SM, but not LL, reduced the time for redness to reach 3.5 by 2-2.6days in MAP O2 and 0.5-0.8days in OW. The greater the proportion of Merino breed type, the shorter was the time for redness to reach the value of 3.5, an effect consistent across muscles and packaging types. In summary, breed type, packaging format, muscle and muscle iron levels had a significant impact on colour stability of sheep meat in oxygen-available packaging systems. Copyright © 2017. Published by Elsevier Ltd.

Circulating Retinol-Binding Protein-4 Concentration Might Reflect Insulin Resistance–Associated Iron Overload

PubMed Central

Fernández-Real, José Manuel; Moreno, José María; Ricart, Wifredo

2008-01-01

OBJECTIVES—The mechanisms behind the association between retinol-binding protein-4 (RBP4) and insulin resistance are not well understood. An interaction between iron and vitamin A status, of which RBP4 is a surrogate, has long been recognized. We hypothesized that iron-associated insulin resistance could be behind the impaired insulin action caused by RBP4. RESEARCH DESIGN AND METHODS—Serum ferritin and RBP4 concentration and insulin resistance were evaluated in a sample of middle-aged men (n = 132) and in a replication independent study. Serum RBP4 was also studied before and after iron depletion in patients with type 2 diabetes. Finally, the effect of iron on RBP4 release was evaluated in vitro in adipose tissue. RESULTS—A positive correlation between circulating RBP4 and log serum ferritin (r = 0.35 and r = 0.61, respectively; P < 0.0001) was observed in both independent studies. Serum RBP4 concentration was higher in men than women in parallel to increased ferritin levels. On multiple regression analyses to predict serum RBP4, log serum ferritin contributed significantly to RBP4 variance after controlling for BMI, age, and homeostasis model assessment value. Serum RBP4 concentration decreased after iron depletion in type 2 diabetic patients (percent mean difference −13.7 [95% CI −25.4 to −2.04]; P = 0.024). The iron donor lactoferrin led to increased dose-dependent adipose tissue release of RBP4 (2.4-fold, P = 0.005) and increased RBP4 expression, while apotransferrin and deferoxamine led to decreased RBP4 release. CONCLUSIONS—The relationship between circulating RBP4 and iron stores, both cross-sectional and after iron depletion, and in vitro findings suggest that iron could play a role in the RBP4–insulin resistance relationship. PMID:18426863

Transcriptional response of Leptospira interrogans to iron limitation and characterization of a PerR homolog.

PubMed

Lo, Miranda; Murray, Gerald L; Khoo, Chen Ai; Haake, David A; Zuerner, Richard L; Adler, Ben

2010-11-01

Leptospirosis is a globally significant zoonosis caused by Leptospira spp. Iron is essential for growth of most bacterial species. Since iron availability is low in the host, pathogens have evolved complex iron acquisition mechanisms to survive and establish infection. In many bacteria, expression of iron uptake and storage proteins is regulated by Fur. L. interrogans encodes four predicted Fur homologs; we have constructed a mutation in one of these, la1857. We conducted microarray analysis to identify iron-responsive genes and to study the effects of la1857 mutation on gene expression. Under iron-limiting conditions, 43 genes were upregulated and 49 genes were downregulated in the wild type. Genes encoding proteins with predicted involvement in inorganic ion transport and metabolism (including TonB-dependent proteins and outer membrane transport proteins) were overrepresented in the upregulated list, while 54% of differentially expressed genes had no known function. There were 16 upregulated genes of unknown function which are absent from the saprophyte L. biflexa and which therefore may encode virulence-associated factors. Expression of iron-responsive genes was not significantly affected by mutagenesis of la1857, indicating that LA1857 is not a global regulator of iron homeostasis. Upregulation of heme biosynthetic genes and a putative catalase in the mutant suggested that LA1857 is more similar to PerR, a regulator of the oxidative stress response. Indeed, the la1857 mutant was more resistant to peroxide stress than the wild type. Our results provide insights into the role of iron in leptospiral metabolism and regulation of the oxidative stress response, including genes likely to be important for virulence.

Role of Iron Uptake Systems in Pseudomonas aeruginosa Virulence and Airway Infection

PubMed Central

Minandri, Fabrizia; Imperi, Francesco; Frangipani, Emanuela; Bonchi, Carlo; Visaggio, Daniela; Facchini, Marcella; Pasquali, Paolo; Bragonzi, Alessandra

2016-01-01

Pseudomonas aeruginosa is a leading cause of hospital-acquired pneumonia and chronic lung infections in cystic fibrosis patients. Iron is essential for bacterial growth, and P. aeruginosa expresses multiple iron uptake systems, whose role in lung infection deserves further investigation. P. aeruginosa Fe3+ uptake systems include the pyoverdine and pyochelin siderophores and two systems for heme uptake, all of which are dependent on the TonB energy transducer. P. aeruginosa also has the FeoB transporter for Fe2+ acquisition. To assess the roles of individual iron uptake systems in P. aeruginosa lung infection, single and double deletion mutants were generated in P. aeruginosa PAO1 and characterized in vitro, using iron-poor media and human serum, and in vivo, using a mouse model of lung infection. The iron uptake-null mutant (tonB1 feoB) and the Fe3+ transport mutant (tonB1) did not grow aerobically under low-iron conditions and were avirulent in the mouse model. Conversely, the wild type and the feoB, hasR phuR (heme uptake), and pchD (pyochelin) mutants grew in vitro and caused 60 to 90% mortality in mice. The pyoverdine mutant (pvdA) and the siderophore-null mutant (pvdA pchD) grew aerobically in iron-poor media but not in human serum, and they caused low mortality in mice (10 to 20%). To differentiate the roles of pyoverdine in iron uptake and virulence regulation, a pvdA fpvR double mutant defective in pyoverdine production but expressing wild-type levels of pyoverdine-regulated virulence factors was generated. Deletion of fpvR in the pvdA background partially restored the lethal phenotype, indicating that pyoverdine contributes to the pathogenesis of P. aeruginosa lung infection by combining iron transport and virulence-inducing capabilities. PMID:27271740

The sulphur oxygenase reductase from Acidianus ambivalens is a multimeric protein containing a low-potential mononuclear non-haem iron centre

PubMed Central

2004-01-01

The SOR (sulphur oxygenase reductase) is the initial enzyme in the sulphur-oxidation pathway of Acidianus ambivalens. Expression of the sor gene in Escherichia coli resulted in active, soluble SOR and in inclusion bodies from which active SOR could be refolded as long as ferric ions were present in the refolding solution. Wild-type, recombinant and refolded SOR possessed indistinguishable properties. Conformational stability studies showed that the apparent unfolding free energy in water is approx. 5 kcal·mol−1 (1 kcal=4.184 kJ), at pH 7. The analysis of the quaternary structures showed a ball-shaped assembly with a central hollow core probably consisting of 24 subunits in a 432 symmetry. The subunits form homodimers as the building blocks of the holoenzyme. Iron was found in the wild-type enzyme at a stoichiometry of one iron atom/subunit. EPR spectroscopy of the colourless SOR resulted in a single isotropic signal at g=4.3, characteristic of high-spin ferric iron. The signal disappeared upon reduction with dithionite or incubation with sulphur at elevated temperature. Thus both EPR and chemical analysis indicate the presence of a mononuclear iron centre, which has a reduction potential of −268 mV at pH 6.5. Protein database inspection identified four SOR protein homologues, but no other significant similarities. The spectroscopic data and the sequence comparison led to the proposal that the Acidianus ambivalens SOR typifies a new type of non-haem iron enzyme containing a mononuclear iron centre co-ordinated by carboxylate and/or histidine ligands. PMID:15030315

Identifying Type Ia Supernova Mechanisms in Dwarf Spheroidal Galaxies through Analysis of Iron-peak Elemental Abundances

NASA Astrophysics Data System (ADS)

Guo, Rachel; Xie, Justin Long; Kirby, Evan N.

2017-01-01

Through the fusion of nucleons to produce elements heavier than hydrogen and helium, stellar nucleosynthesis produces most of the elements in the universe. Such is the case in a supernova explosion, which creates most of the elements on the periodic table—including iron-peak elements, atomic numbers 21 through 30—through nucleosynthesis and ejects them into the interstellar medium. In this study, we determine the best theoretical supernova model appropriate for the stars in the dwarf spheroidal galaxies Sculptor, Fornax, Ursa Minor, and Leo II by calculating the abundances of iron-peak elements in these stars. To determine iron-peak elemental abundances, we compare synthesized spectra with observed spectra from medium-resolution spectroscopy and determine the best-fitting spectrum by way of a chi-squared minimization. Through inspecting the relationship between the iron-peak element abundances and the abundance of iron itself and by comparing them to previously hypothesized supernova model theories, we discover that the near-Chandrasekhar mass “n1” model, as predicted by Seitenzahl et al., most accurately represents the trends and patterns within our data, presenting new insight into Type Ia supernovae mechanisms within the Milky Way and beyond.

Hepatic Iron Overload and Hepatocellular Carcinoma

PubMed Central

Kew, Michael C.

2014-01-01

In recent years it has become increasingly evident that excess body iron may be complicated by the supervention of hepatocellular carcinoma (HCC). Hereditary hemochromatosis (HH) was the first condition in which hepatic iron overload was shown to predispose to the development of HCC. The inherited predisposition to excessive absorption of dietary iron in HH is almost always the result of homozygosity of the C282Y mutation of the HFE gene, which causes inappropriately low secretion of hepcidin. HCC develops in 8-10% of patients with HH and is responsible for approximately 45% of deaths in the HCC patients. Cirrhosis is almost always present when HCC is diagnosed. Dietary iron overload is a condition which occurs in rural-dwelling Black Africans in southern Africa as a result of the consumption, over time, of large volumes of alcohol home-brewed in iron containers and having, as a consequence, a high iron content. Iron loading of the liver results and may be complicated by malignant transformation of the liver (relative risk of approximately 10.0). Accompanying cirrhosis does occur but is less common than that in HH. The development of HCC as a consequence of increased dietary iron, and the fact that it may develop in the absence of cirrhosis, has been confirmed in an animal model. Drinking water with a high iron content might contribute to the high incidence of HCC in parts of Taiwan. The metabolic syndrome [obesity, insulin resistance type 2 (or diabetes mellitus type 2), non-alcoholic fatty liver or non-alcoholic steatohepatitis] has in recent years become a major public health problem in some resource-rich countries. A link between excess body iron and insulin resistance or the metabolic syndrome has become apparent. The metabolic syndrome may be complicated by the supervention of HCC, and recent evidence suggests that increased body iron may contribute to this complication. PMID:24804175

Iron Binding at Specific Sites within the Octameric HbpS Protects Streptomycetes from Iron-Mediated Oxidative Stress

PubMed Central

Wedderhoff, Ina; Kursula, Inari; Groves, Matthew R.; Ortiz de Orué Lucana, Darío

2013-01-01

The soil bacterium Streptomyces reticuli secretes the octameric protein HbpS that acts as a sensory component of the redox-signalling pathway HbpS-SenS-SenR. This system modulates a genetic response on iron- and haem-mediated oxidative stress. Moreover, HbpS alone provides this bacterium with a defence mechanism to the presence of high concentrations of iron ions and haem. While the protection against haem has been related to its haem-binding and haem-degrading activity, the interaction with iron has not been studied in detail. In this work, we biochemically analyzed the iron-binding activity of a set of generated HbpS mutant proteins and present evidence showing the involvement of one internal and two exposed D/EXXE motifs in binding of high quantities of ferrous iron, with the internal E78XXE81 displaying the tightest binding. We additionally show that HbpS is able to oxidize ferrous to ferric iron ions. Based on the crystal structure of both the wild-type and the mutant HbpS-D78XXD81, we conclude that the local arrangement of the side chains from the glutamates in E78XXE81 within the octameric assembly is a pre-requisite for interaction with iron. The data obtained led us to propose that the exposed and the internal motif build a highly specific route that is involved in the transport of high quantities of iron ions into the core of the HbpS octamer. Furthermore, physiological studies using Streptomyces transformants secreting either wild-type or HbpS mutant proteins and different redox-cycling compounds led us to conclude that the iron-sequestering activity of HbpS protects these soil bacteria from the hazardous side effects of peroxide- and iron-based oxidative stress. PMID:24013686

The impact of H63D HFE gene carriage on hemoglobin and iron status in children.

PubMed

Barbara, Kaczorowska-Hac; Marcin, Luszczyk; Jedrzej, Antosiewicz; Wieslaw, Ziolkowski; Elzbieta, Adamkiewicz-Drozynska; Malgorzata, Mysliwiec; Ewa, Milosz; Jacek, Kaczor Jan

2016-12-01

The molecular mechanism that regulates iron homeostasis is based on a network of signals, which reflect on the iron requirements of the body. Hereditary hemochromatosis is a heterogenic metabolic syndrome which is due to unchecked transfer of iron into the bloodstream and its toxic effects on parenchymatous organs. It is caused by the mutation of genes that encode proteins that help hepcidin to monitor serum iron. These proteins include the human hemochromatosis protein -HFE, transferrin-receptor 2, hemojuvelin in rare instances, and ferroportin. HFE-related hemochromatosis is the most frequent form of the disease. Interestingly, the low penetrance of polymorphic HFE genes results in rare clinical presentation of the disease, predominantly in middle-aged males. Taking into account the wide dispersion of HFE mutation in our population and also its unknown role in heterozygotes, we analyzed the impact of H63D HFE carriage in the developmental age, with respect to gender, on the iron status and hemoglobin concentration of carriers in comparison to those of wild-type HFE gene (12.7 ± 3.07 years, 42 boys and 41 girls). H63D carriers presented higher blood iron, transferrin saturation, and ferritin concentration than wild-type probands (p < 0.05.) Interestingly, male H63D carriers showed higher hemoglobin concentration than the unburdened children. Moreover, in the H63D carrier group, a positive correlation between iron and hemoglobin was noted. In conclusion, this study demonstrates that changes in iron metabolism occur at a young age in HFE heterozygotes.

Enhanced carcinogenicity by coexposure to arsenic and iron and a novel remediation system for the elements in well drinking water.

PubMed

Kumasaka, Mayuko Y; Yamanoshita, Osamu; Shimizu, Shingo; Ohnuma, Shoko; Furuta, Akio; Yajima, Ichiro; Nizam, Saika; Khalequzzaman, Md; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

2013-03-01

Various carcinomas including skin cancer are explosively increasing in arsenicosis patients who drink arsenic-polluted well water, especially in Bangladesh. Although well drinking water in the cancer-prone areas contains various elements, very little is known about the effects of elements except arsenic on carcinogenicity. In order to clarify the carcinogenic effects of coexposure to arsenic and iron, anchorage-independent growth and invasion in human untransformed HaCaT and transformed A431 keratinocytes were examined. Since the mean ratio of arsenic and iron in well water was 1:10 in cancer-prone areas of Bangladesh, effects of 1 μM arsenic and 10 μM iron were investigated. Iron synergistically promoted arsenic-mediated anchorage-independent growth in untransformed and transformed keratinocytes. Iron additionally increased invasion in both types of keratinocytes. Activities of c-SRC and ERK that regulate anchorage-independent growth and invasion were synergistically enhanced in both types of keratinocytes. Our results suggest that iron promotes arsenic-mediated transformation of untransformed keratinocytes and progression of transformed keratinocytes. We then developed a low-cost and high-performance adsorbent composed of a hydrotalcite-like compound for arsenic and iron. The adsorbent rapidly reduced concentrations of both elements from well drinking water in cancer-prone areas of Bangladesh to levels less than those in WHO health-based guidelines for drinking water. Thus, we not only demonstrated for the first time increased carcinogenicity by coexposure to arsenic and iron but also proposed a novel remediation system for well drinking water.

The Effect Of Local Coal And Smelting Sponge Iron On Iron Content Of Pig Iron

NASA Astrophysics Data System (ADS)

Oediyani, Soesaptri; Juwita Sari, Pramita; Hadi P, Djoko

2018-03-01

The new regulation on mineral resources was announced by Ministry of Energy and Mineral resources (ESDM) of Indonesia at 2014 which it called Permen ESDM No 1/2014. Therefore, this research was conducted to add the value of local iron ores by using smelting technology. The objective of the research is to produce pig iron that meet the requirement of the new regulation of mineral resources such as 90% Fe. First, iron ores and coal mixed together with lime as a flux, then smelted in a Electric Arc Furnace at 1800°C. The process variables are (1; 1.25; 1.5; 1.75; 2.0) and the composition of coal (0.8%, 1.6%, 3.0%). The type of coal that used in this research was bituminous coal from Kalimantan and also the iron ores from Kalimantan. The products of the smelting technology are Pig iron and slag. Both pig iron and slag then analyzed by SEM-EDS to measure the iron content. The result shows that the maximum iron content on pig iron is about 95.04% meanwhile the minimum iron content on slag is about 3.66%. This result achieved at 1.6% coal and 2.0.

Functional Properties of Pea (Pisum sativum, L.) Protein Isolates Modified with Chymosin

PubMed Central

Barać, Miroljub; Čabrilo, Slavica; Pešić, Mirjana; Stanojević, Slađana; Pavlićević, Milica; Maćej, Ognjen; Ristić, Nikola

2011-01-01

In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren). The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and 8.0) was monitored. Chymosin can be a very useful agent for improvement of functional properties of isolates. Action of this enzyme caused a low degree of hydrolysis (3.9–4.7%), but improved significantly functional properties of pea protein isolates (PPI), especially at lower pH values (3.0–5.0). At these pH values all hydrolysates had better solubility, emulsifying activity and foaming stability, while longer-treated samples (60 min) formed more stable emulsions at higher pH values (7.0, 8.0) than initial isolates. Also, regardless of pH value, all hydrolysates showed improved foaming ability. A moderate positive correlation between solubility and emulsifying activity index (EAI) (0.74) and negative correlation between solubility and foam stability (−0.60) as well as between foam stability (FS) and EAI (−0.77) were observed. Detected enhancement in functional properties was a result of partial hydrolysis of insoluble protein complexes. PMID:22272078

Sintering of wax for controlling release from pellets.

PubMed

Singh, Reena; Poddar, S S; Chivate, Amit

2007-09-14

The purpose of the present study was to investigate incorporation of hydrophobic (ie, waxy) material into pellets using a thermal sintering technique and to evaluate the pellets in vitro for controlled release. Pellets prepared by extrusion-spheronization technology were formulated with a water-soluble drug, microcrystalline cellulose, and carnauba wax. Powdered carnauba wax (4%-20%) prepared by grinding or by emulsification was studied with an attempt to retard the drug release. The inclusion of ground or emulsified carnauba wax did not sustain the release of theophylline for more than 3 hours. Matrix pellets of theophylline prepared with various concentrations of carnauba wax were sintered thermally at various times and temperatures. In vitro drug release profiles indicated an increase in drug release retardation with increasing carnauba wax concentration. Pellets prepared with ground wax showed a higher standard deviation than did those prepared with emulsified wax. There was incomplete release at the end of 12 hours for pellets prepared with 20% ground or emulsified wax. The sintering temperature and duration were optimized to allow for a sustained release lasting at least 12 hours. The optimized temperature and duration were found to be 100 degrees C and 140 seconds, respectively. The sintered pellets had a higher hydrophobicity than did the unsintered pellets. Scanning electron micrographs indicated that the carnauba wax moved internally, thereby increasing the surface area of wax within the pellets.

A quality by design approach to optimization of emulsions for electrospinning using factorial and D-optimal designs.

PubMed

Badawi, Mariam A; El-Khordagui, Labiba K

2014-07-16

Emulsion electrospinning is a multifactorial process used to generate nanofibers loaded with hydrophilic drugs or macromolecules for diverse biomedical applications. Emulsion electrospinnability is greatly impacted by the emulsion pharmaceutical attributes. The aim of this study was to apply a quality by design (QbD) approach based on design of experiments as a risk-based proactive approach to achieve predictable critical quality attributes (CQAs) in w/o emulsions for electrospinning. Polycaprolactone (PCL)-thickened w/o emulsions containing doxycycline HCl were formulated using a Span 60/sodium lauryl sulfate (SLS) emulsifier blend. The identified emulsion CQAs (stability, viscosity and conductivity) were linked with electrospinnability using a 3(3) factorial design to optimize emulsion composition for phase stability and a D-optimal design to optimize stable emulsions for viscosity and conductivity after shifting the design space. The three independent variables, emulsifier blend composition, organic:aqueous phase ratio and polymer concentration, had a significant effect (p<0.05) on emulsion CQAs, the emulsifier blend composition exerting prominent main and interaction effects. Scanning electron microscopy (SEM) of emulsion-electrospun NFs and desirability functions allowed modeling of emulsion CQAs to predict electrospinnable formulations. A QbD approach successfully built quality in electrospinnable emulsions, allowing development of hydrophilic drug-loaded nanofibers with desired morphological characteristics. Copyright © 2014 Elsevier B.V. All rights reserved.

Emulsifying and foaming properties of commercial yellow pea (Pisum sativum L.) seed flours.

PubMed

Aluko, Rotimi E; Mofolasayo, Olawunmi A; Watts, Beverley M

2009-10-28

Commercial yellow pea seed flours prepared by a patented wet-milling process and pea protein isolate (PPI) were analyzed for emulsifying and foaming properties at pH 3.0, 5.0, and 7.0 and compared to soybean protein isolate (SPI). PPI and SPI formed emulsions with significantly smaller (p < 0.05) oil droplet sizes, 16-30 and 23-54 microm, respectively, than flours that primarily contained fiber such as Centara III and IV, or those that consisted mainly of starch: Centu-tex, Uptake 80 and Accu-gel. PPI was a better emulsifier than SPI at pH 7.0, and a better foaming agent at pH 3.0 and pH 7.0, although foaming capacity varied with sample concentration. Centu-tex and Uptake 80 have exactly the same chemical composition, but the latter has a much smaller flour particle size range, and had significantly smaller (p < 0.05) emulsion oil droplets. Incorporation of pea starch into SPI emulsions produced a synergistic effect that led to significant increases (p < 0.05) in emulsification capacity (reduced emulsion oil droplet size) when compared to SPI or starch alone. These results showed that PPI had generally significantly higher (p < 0.05) emulsion and foam forming properties than SPI, and that pea starch could be used to improve the quality of SPI-stabilized food emulsions.

Measuring the emulsification dynamics and stability of self-emulsifying drug delivery systems.

PubMed

Vasconcelos, Teófilo; Marques, Sara; Sarmento, Bruno

2018-02-01

Self-emulsifying drug delivery systems (SEDDS) are one of the most promising technologies in the drug delivery field, particularly for addressing solubility and bioavailability issues of drugs. The development of these drug carriers excessively relies in visual observations and indirect determinations. The present manuscript intended to describe a method able to measure the emulsification of SEDDS, both micro and nano-emulsions, able to measure the droplet size and to evaluate the physical stability of these formulations. Additionally, a new process to evaluate the physical stability of SEDDS after emulsification was also proposed, based on a cycle of mechanical stress followed by a resting period. The use of a multiparameter continuous evaluation during the emulsification process and stability was of upmost value to understand SEDDS emulsification process. Based on this method, SEDDS were classified as fast and slow emulsifiers. Moreover, emulsification process and stabilization of emulsion was subject of several considerations regarding the composition of SEDDS as major factor that affects stability to physical stress and the use of multicomponent with different properties to develop a stable and robust SEDDS formulation. Drug loading level is herein suggested to impact droplets size of SEDDS after dispersion and SEDDS stability to stress conditions. The proposed protocol allows an online measurement of SEDDS droplet size during emulsification and a rationale selection of excipients based on its emulsification and stabilization performance. Copyright © 2017. Published by Elsevier B.V.

Characterization of flaxseed oil emulsions.

PubMed

Lee, Pei-En; Choo, Wee-Sim

2015-07-01

The emulsifying capacity of surfactants (polysorbate 20, polysorbate 80 and soy lecithin) and proteins (soy protein isolate and whey protein isolate) in flaxseed oil was measured based on 1 % (w/w) of emulsifier. Surfactants showed significantly higher emulsifying capacity compared to the proteins (soy protein isolate and whey protein isolate) in flaxseed oil. The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a mixer was ranked in the following order: 1,000 rpm (58 min) ≈ 1,000 rpm (29 min) ≈ 2,000 rpm (35 min) >2,000 rpm (17.5 min). The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a homogenizer (Ultra Turrax) was independent of the speed and mixing time. The mean particle size of the flaxseed oil emulsions prepared using the two mixing devices ranged from 23.99 ± 1.34 μm to 47.22 ± 1.99 μm where else the particle size distribution and microstructure of the flaxseed oil emulsions demonstrated using microscopic imaging were quite similar. The flaxseed oil emulsions had a similar apparent viscosity and exhibited shear thinning (pseudoplastic) behavior. The flaxseed oil emulsions had L* value above 70 and was in the red-yellow color region (positive a* and b* values).

Emulsifying and Foaming Properties of Different Protein Fractions Obtained from a Novel Lupin Variety AluProt-CGNA(®) (Lupinus luteus).

PubMed

Burgos-Díaz, César; Piornos, José A; Wandersleben, Traudy; Ogura, Takahiro; Hernández, Xaviera; Rubilar, Mónica

2016-07-01

The use of vegetable proteins as food ingredient is becoming increasingly important due to their high versatility and environmental acceptability. This work describes a chemical characterization and techno-functional properties (emulsifying and foaming properties) of 3 protein fractions obtained from a protein-rich novel lupin variety, AluProt-CGNA(®) . This nongenetically modified variety have a great protein content in dehulled seeds (60.6 g protein/100 g, dry matter), which is higher than soybean and other lupin varieties. A simple procedure was utilized to obtain 3 different fractions by using alkali solubilization and isoelectric precipitation. Fractions 1 and 3 were mainly composed of protein and polysaccharides (NNE), whereas fraction 2 was mainly composed by protein (97%, w/w). Fraction 3 presented interesting and potential foaming properties in comparison to the other fractions evaluated in the study. Besides, its solubility, foaming and emulsifying capacity were practically not affected by pH variations. The 3 fractions also presented good emulsion stability, reaching values above a 95%. SDS-PAGE showed that fractions 1 and 2 contained mainly conglutin α, β, and δ, but in different ratios, whereas fraction 3 contained mainly conglutin γ and albumins. The results of this work will provide better understanding for the utilization of each protein fractions as potential ingredients in food industry. © 2016 Institute of Food Technologists®

Effect of interfacial composition and crumbliness on aroma release in soy protein/sugar beet pectin mixed emulsion gels.

PubMed

Hou, Jun-Jie; Guo, Jian; Wang, Jin-Mei; Yang, Xiao-Quan

2016-10-01

In this study, soy protein isolate/sugar beet pectin (SPI/SBP) emulsion gels were prepared through an enzymatic gelation process. The effects of emulsifier (SBP, SPI or SPI/SBP complex) and emulsification process on the microstructure, texture, breakdown properties and aroma release behavior of resulting emulsion gels were investigated. Oil emulsification by SBP/SPI complex resulted in a higher amount of emulsifier absorbing on the oil-water interface than by SBP and SPI alone, indicating that a more compact interfacial network was formed. Flocculation of oil droplets was observed and corresponding emulsion gels exhibited lower fracture force and strain when the oil was emulsified by SPI and SBP/SPI complex. Moreover, emulsion gels with small droplets produced a greater quantity of small fragments after mastication. However, microstructure did not have a significant effect on breakdown properties of emulsion gels. Headspace gas chromatography analysis showed that the release rate of ethyl butyrate before and after mastication was significantly lower in emulsion gel with more compact network, but the release of aroma compounds with higher hydrophobicity did not show a significant influence of the microstructure and texture of emulsion gel. This finding provides a useful application for designing semi-solid foods with desirable flavor perception. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

The oxidative stability of omega-3 oil-in-water nanoemulsion systems suitable for functional food enrichment: A systematic review of the literature.

PubMed

Bush, Linda; Stevenson, Leo; Lane, Katie E

2017-10-23

There is growing demand for functional food products enriched with long chain omega-3 polyunsaturated fatty acids (LCω3PUFA). Nanoemulsions, systems with extremely small droplet sizes have been shown to increase LCω3PUFA bioavailability. However, nanoemulsion creation and processing methods may impact on the oxidative stability of these systems. The present systematic review collates information from studies that evaluated the oxidative stability of LCω3PUFA nanoemulsions suitable for use in functional foods. The systematic search identified seventeen articles published during the last 10 years. Researchers used a range of surfactants and antioxidants to create systems which were evaluated from 7 to 100 days of storage. Nanoemulsions were created using synthetic and natural emulsifiers, with natural sources offering equivalent or increased oxidative stability compared to synthetic sources, which is useful as consumers are demanding natural, cleaner label food products. Equivalent vegetarian sources of LCω3PUFA found in fish oils such as algal oils are promising as they provide direct sources without the need for conversion in the human metabolic pathway. Quillaja saponin is a promising natural emulsifier that can produce nanoemulsion systems with equivalent/increased oxidative stability in comparison to other emulsifiers. Further studies to evaluate the oxidative stability of quillaja saponin nanoemulsions combined with algal sources of LCω3PUFA are warranted.

Shear flow behaviour and emulsion-stabilizing effect of natural polysaccharide-protein gum in aqueous system and oil/water (O/W) emulsion.

PubMed

Amid, Bahareh Tabatabaee; Mirhosseini, Hamed

2013-03-01

The main objective of the current work was to characterize the shear rheological flow behaviour and emulsifying properties of the natural biopolymer from durian seed. The present study revealed that the extraction condition significantly affected the physical and functional characteristics of the natural biopolymer from durian seed. The dynamic oscillatory test indicated that the biopolymer from durian seed showed more gel (or solid) like behaviour than the viscous (or liquid) like behaviour (G'>G″) at a relatively high concentration (20%) in the fixed frequency (0.1 Hz). This might be explained by the fact that the gum coils disentangle at low frequencies during the long period of oscillation, thus resulting in more gel like behaviour than the viscous like behaviour. The average droplet size of oil in water (O/W) emulsions stabilized by durian seed gum significantly varied from 0.42 to 7.48 μm. The results indicated that O/W emulsions showed significant different stability after 4 months storage. This might be interpreted by the considerable effect of the extraction condition on the chemical and molecular structure of the biopolymer, thus affecting its emulsifying capacity. The biopolymer extracted by using low water to seed (W/S) ratio at the low temperature under the alkaline condition showed a relatively high emulsifying activity in O/W emulsion. Copyright © 2012 Elsevier B.V. All rights reserved.

Antibacterial Activity of Emulsified Pomelo (Citrus grandis Osbeck) Peel Oil and Water-Soluble Chitosan on Staphylococcus aureus and Escherichia coli.

PubMed

Chen, Guan-Wen; Lin, Yu-Hsin; Lin, Chia-Hua; Jen, Hsiao-Chin

2018-04-06

This study utilized pomelo steam distillation to isolate pomelo peel essential oil. The constituents were then analyzed through gas chromatography-mass spectrometry (GC-MS), and the antibacterial activity of the essential oil emulsions at different homogenizer speed conditions and concentrations of water-soluble chitosan (degree of acetylation, DA = 54.8%) against S. aureus and E. coli was examined. Analysis of the essential oil composition identified a total of 33 compounds with the main constituent, limonene accounting for 87.5% (940.07 mg/g) of the total. The pomelo peel oil was emulsified through homogenization at 24,000 rpm, resulting in a minimal inhibitory concentration (MIC) for E. coli that was 1.9 times lower than that of the essential oil without homogenization. In addition, a mixture of 0.4% essential oil emulsion and 0.03% water-soluble chitosan had the strongest synergetic antibacterial effect on S. aureus and E. coli at pH 7.4. In comparison with chitosan alone, the MIC value of this mixture was significantly 2.4 and 2.5 times lower. Hence, this study suggests using a mixture of emulsified pomelo peel oil and water-soluble chitosan to develop a novel natural food preservative, and that the processability of food, as well as the economic value of the byproducts of the Taiwan Matou pomelo and chitosan, could be increased.

Physicochemical and FTIR Study of Diesel-Hydrogen Peroxide Fuel Blend

NASA Astrophysics Data System (ADS)

Saad Khan, Muhammad; Ahmed, Iqbal; Lal, Bhajan; Idris, Al-Amin; Albeirutty, Muhammad H.; Ayoub, Muhammad; Sufian, Suriati binti

2018-04-01

Physicochemical properties of combustion fuels play a key role in determining the qualitative and quantitative characteristics, reliability and health effects associated with emissions. This paper reports the preparation of polysaccharide (PS) based emulsifier for stable blending of petroleum diesel-hydrogen peroxide (H2O2) and investigated the influence of H2O2 as diesel fuel blends on the physicochemical properties and characteristics. The quantity of PS-emulsifier was kept at 5 volume % (vol. %) and the volume ratio of H2O2 were varied 5-15 vol. % to reference diesel (RD), respectively. The blended diesel/H2O2 fuel were prepared under inert oxygen (O2) gas closed heating system; afterthought, physiochemical properties of diesel/H2O2 blend were evaluated at standard ASTM D-975 testing method. The kinetic properties show the interaction of RD and H2O2 blend at presence of PS emulsifier which exhibit the phenomenon to diminish the interfacial tension among the two different phases to form a homogenized stable solution. Results revealed that H2O2 is capable of enhancing the diesel fuel properties and showed that the addition of H2O2 in a diesel fuel blend are lied within the ranges of standard ASTM D-975. Due to further oxygen atom present in H2O2, it can facilitate the combustion process which ultimately effect on exhaust emission.

Multimodal cues drive host-plant assessment in Asian citrus psyllid (Diaphorina citri).

PubMed

Patt, Joseph M; Meikle, William G; Mafra-Neto, Agenor; Sétamou, Mamoudou; Mangan, Robert; Yang, Chenghai; Malik, Nasir; Adamczyk, John J

2011-12-01

Asian citrus psyllid (Diaphorina citri) transmits the causal agent of Huanglongbing, a devastating disease of citrus trees. In this study we measured behavioral responses of D. citri to combinations of visual, olfactory, and gustatory stimuli in test arenas. Stimuli were presented to the psyllids in droplets or lines of an emulsified wax formulation in two different arena types in no-choice tests. First, when placed on a colored ring situated halfway between the center and perimeter of a petri dish, D. citri spent more time on yellow versus gray rings; however, this response disappeared when either gray or yellow wax droplets were applied. When the psyllids were presented with droplets scented with terpenes, the response to both scent and color was increased. The addition of a dilute (≍0.1 M) sucrose solution to the wax droplets increased the magnitude of D. citri responses. Next, groups of D. citri were placed on plastic laboratory film covering a sucrose solution, to mimic a leaf surface. Test stimuli were presented via two 'midribs' made from lines of emulsified wax formulation. Probing levels were measured as a function of color saturation and scent composition, and concentration. The test scents were based on qualitatively major volatiles emitted by Murraya paniculata (L.) Jack, Citrus aurantifolia (Christm.) Swingle, and C. sinensis (L.) Osbeck. The highest probing response was observed on the middle concentration (20-μl scent/10 ml wax formulation) of the C. aurantifolia-scented wax lines. Results indicate that there are interactive effects between the different sensory modalities in directing host-plant assessment behavior.

Self-emulsifying drug delivery system improves preventive effect of curcuminoids on chronic heart failure in rats.

PubMed

Jiang, Yunbin; Wang, Junzhi; Wang, Yunhong; Ke, Xiumei; Zhang, Chuanhui; Yang, Rongping

2018-05-01

Several studies have reported the preventive or therapeutic effect of curcuminoids on chronic heart failure (CHF), but their application was limited due to low solubility and bioavailability. Our previous study indicates that self-emulsifying drug delivery system (SEDDS) improves the solubility and bioavailability of curcuminoids. Thus, the aim of this work was to investigate whether SEDDS could improve preventive effect of curcuminoids on CHF in rats. CHF model was were established by coronary artery ligation. Ninety rats were randomly and averagely divided into sham, model, low- or high-dose suspension or SEDDS of curcuminoids (66.68 or 266.68 mg/kg) groups. Hemodynamic indices were recorded by multipurpose polygraph. Serum oxidative indices, B-type natriuretic peptide (BNP) and heart weight index were determined by kits and electronic balance. Myocardial infarct area, ventricular dilatation degree and collagen volume fraction of myocardial interstitium were analyzed by Masson staining, picric acid and sirius red staining, light microscopy and image analysis system. Myocardial histopathology was observed by hematoxylin and eosin staining, Masson staining and light microscopy. Reduction of ventricular pump function, increase of BNP level and heart weight index, myocardial lipid peroxidation damage, myocardial infarction, myocardial fibrosis, and cardiac enlargement were detected or observed in model group relative to those in sham group. After treatment with suspension or SEDDS of curcuminoids, the above-mentioned pathological changes were obviously reversed relative to those in model group. Meanwhile, the ameliorative effect of SEDDS of curcuminoids was markedly better than that of suspension of curcuminoids. This work provides a valuable reference from pharmacodynamics for development of curcuminoids pharmaceutics.

Did the Kiruna iron ores form as a result of a metasomatic or igneous process? New U-Pb and Nd data for the iron oxide apatite ores and their host rocks in the Norrbotten region of northern Sweden

NASA Astrophysics Data System (ADS)

Westhues, A.; Hanchar, J. M.; Whitehouse, M. J.; Fisher, C. M.

2012-12-01

A number of iron deposits near Kiruna in the Norrbotten region of northern Sweden are of the iron oxide apatite (IOA) type of deposits; also referred to as Kiruna-type deposits. They are commonly considered a subgroup or end-member of iron oxide copper gold (IOCG) deposits, containing no economic grades of copper or gold. Both IOCG and IOA deposits are characterized by abundant low-Ti Fe oxides, an enrichment in REE, and intense sodium and potassium wall-rock alteration adjacent to the ores. Deposits of these types are of a great economic importance, not only for iron, but also for other elements such as rare earth elements (REE) or uranium. Kiruna, the type locality of the IOA type of mineral deposits, is the focus of this study. Despite a century-long mining history and 2500 Mt of iron ore produced in the region to date (with grades of 30 to 70 wt.% Fe), the genesis of these deposits is poorly understood: theories of a magmatic vs. a hydrothermal or metasomatic origin have been debated, and the timing of mineralization of the ores in the Norbotten region has never been directly dated. The results anticipated from this study will provide a better understanding of the nature of the IOA type of mineral deposits and their relation to IOCG deposits such as Olympic Dam in Australia. An array of geochemical methods is used in order to gain insights on the emplacement history of the host rocks, their subsequent alteration, and the ore genesis of these deposits. This includes in situ U/Pb geochronology of zircon, monazite, and titanite to constrain the timing between host rock emplacement, alteration and mineralization. Isotopic data from whole rocks and in situ at mineral scale will provide constraints on the involvement of hydrothermal fluids and their possible sources, as well as on the sources of Fe, U, and the REE. Newly obtained Sm-Nd isotopic data points to distinct source differences between host rocks, ore and alteration related samples. Preliminary in situ U-Pb dating of zircon from both host rock and ore samples confirms a previously documented event around 1880 - 1900 Ma in the Norrbotten region. However, U-Pb in monazite from an ore sample suggests a further event at ca. 1650 Ma, a period of known activity in Fennoscandia. Further investigation and more U-Pb data are needed to confirm those dates and how the iron mineralization is related to those two events. The combination of U-Th-Pb ages, tracer isotopes and trace element abundances at mineral scale (e.g., Lu-Hf in zircon, and Sm-Nd in monazite, apatite, titanite), along with the O isotopic composition of zircon, will be used to decipher whether the Kiruna iron ore deposits are of metasomatic or igneous origin. Overall, the study also intends to develop a predictive model for exploration of similar iron oxide apatite deposits worldwide.

Threshold-type dose response for induction of neoplastic transformation by 1 GeV/nucleon iron ions.

PubMed

Elmore, E; Lao, X-Y; Kapadia, R; Redpath, J L

2009-06-01

Neoplastic transformation of HeLa x skin fibroblast human hybrid cells by doses of 1 GeV/nucleon iron ions in the range 1 cGy to 1 Gy to exposed cultures has been examined. The data indicate a threshold-type dose-response curve with no increase in transformation frequency until doses above 20 cGy. At doses <10 cGy, not all exposed cells receive a direct traversal of an iron-ion track core, but all exposed cells receive up to several mGy of low-LET radiation associated with the delta-ray penumbra. It is proposed that the threshold-type response seen is a consequence of an adaptive response associated with the delta-ray exposure. For comparison purposes, the dose response for (137)Cs gamma rays over the same dose range was examined using the same experimental procedure. As we have shown previously, the dose response for (137)Cs gamma radiation was J-shaped. The iron ions were 1.5 to 1.7 times more biologically effective than the gamma radiation over the dose range examined.

Ferritin accumulation under iron scarcity in Drosophila iron cells.

PubMed

Mehta, A; Deshpande, A; Bettedi, L; Missirlis, F

2009-10-01

Ferritins are highly stable, multi-subunit protein complexes with iron-binding capacities that reach 4500 iron atoms per ferritin molecule. The strict dependence of cellular physiology on an adequate supply of iron cofactors has likely been a key driving force in the evolution of ferritins as iron storage molecules. The insect intestine has long been known to contain cells that are responsive to dietary iron levels and a specialized group of "iron cells" that always accumulate iron-loaded ferritin, even when no supplementary iron is added to the diet. Here, we further characterize ferritin localization in Drosophila melanogaster larvae raised under iron-enriched and iron-depleted conditions. High dietary iron intake results in ferritin accumulation in the anterior midgut, but also in garland (wreath) cells and in pericardial cells, which together filter the circulating hemolymph. Ferritin is also abundant in the brain, where levels remain unaltered following dietary iron chelation, a treatment that depletes ferritin from the aforementioned tissues. We attribute the stability of ferritin levels in the brain to the function of the blood-brain barrier that may shield this organ from systemic iron fluctuations. Most intriguingly, our dietary manipulations demonstrably iron-depleted the iron cells without a concomitant reduction in their production of ferritin. Therefore, insect iron cells may constitute an exception from the evolutionary norm with respect to iron-dependent ferritin regulation. It will be of interest to decipher both the physiological purpose served and the mechanism employed to untie ferritin regulation from cellular iron levels in this cell type.

Phonon properties of iron-based superconductors

NASA Astrophysics Data System (ADS)

Gupta, Yuhit; Goyal, Megha; Sinha, M. M.

2018-05-01

Earlier, it was thought there is antagonist relationship between superconductivity and ferromagnetic materials, But, a discovery of iron-based superconductors have removed this misconception. It gives an idea to make a review on the superconductivity properties of different materials. The new iron-based superconductors' present symmetry breaking competing phases in the form of tetragonal to orthorhombic transition. It consists of mainly four families [1111], [111], [122], and [11] type. Superconductivity of iron-based superconductors mainly related with the phonons and there is an excellent relation between phonons and superconductivity. Phonons properties are helpful in predicting the superconducting properties of materials. Phonon properties of iron-based superconductors in various phases are summarized in this study. We are presenting the review of phonon properties of iron-based superconductors.

21 CFR 184.1366 - Hydrogen peroxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... agent. Wine vinegar Amount sufficient for the purpose Remove sulfur dioxide from wine prior to fermentation to produce vinegar. Emulsifiers containing fatty acid esters 1.25 Bleaching agent. (d) Residual...

Local environment of iron in garden soil Vs Plants

NASA Astrophysics Data System (ADS)

Dehipawala, Sunil; Dong, Chaojung; Smith, Stephen; Schneider, Patricia; Gafney, Harry

2015-03-01

Iron is an essential nutrient not only for humans, but also for all types of plants. Plants use iron for chlorophyll formation, RNA metabolism, and transpiration process regulation. Iron is one of the most abundant metals in the soil and occurs in a wide range of chemical forms. The correlation between the iron species presents in soil and in Petroselinum crispum (parsley) plants were investigated using the room temperature Mossbauer spectroscopy. Mossbauer spectrum of garden soil consists of two doublets. Based on the established isomer shift and quadrupole splitting values of iron, these doublets can be identified as due to octahedrally coordinated Fe3+ and tetrahedrally coordinated Fe2+. Most of the iron present in the parsley has the form Fe3+ or electron density at the site of the iron nucleus similar to that of Fe3+. These findings will help establish soil conditions necessary to increase Fe2+ intake by plants similar to the form of iron present in most supplements. Sunil Dehipawala acknowledges financial support provided by PSC-CUNY.

Lack of Plasma Protein Hemopexin Results in Increased Duodenal Iron Uptake.

PubMed

Fiorito, Veronica; Geninatti Crich, Simonetta; Silengo, Lorenzo; Aime, Silvio; Altruda, Fiorella; Tolosano, Emanuela

2013-01-01

The body concentration of iron is regulated by a fine equilibrium between absorption and losses of iron. Iron can be absorbed from diet as inorganic iron or as heme. Hemopexin is an acute phase protein that limits iron access to microorganisms. Moreover, it is the plasma protein with the highest binding affinity for heme and thus it mediates heme-iron recycling. Considering its involvement in iron homeostasis, it was postulated that hemopexin may play a role in the physiological absorption of inorganic iron. Hemopexin-null mice showed elevated iron deposits in enterocytes, associated with higher duodenal H-Ferritin levels and a significant increase in duodenal expression and activity of heme oxygenase. The expression of heme-iron and inorganic iron transporters was normal. The rate of iron absorption was assessed by measuring the amount of (57)Fe retained in tissues from hemopexin-null and wild-type animals after administration of an oral dose of (57)FeSO4 or of (57)Fe-labelled heme. Higher iron retention in the duodenum of hemopexin-null mice was observed as compared with normal mice. Conversely, iron transfer from enterocytes to liver and bone marrow was unaffected in hemopexin-null mice. The increased iron level in hemopexin-null duodenum can be accounted for by an increased iron uptake by enterocytes and storage in ferritins. These data indicate that the lack of hemopexin under physiological conditions leads to an enhanced duodenal iron uptake thus providing new insights to our understanding of body iron homeostasis.

Preparation and mechanical properties of edible rapeseed protein films.

PubMed

Jang, Sung-Ae; Lim, Geum-Ok; Song, Kyung Bin

2011-03-01

Edible films were manufactured from rapeseed oil extraction residues. To prepare rapeseed protein (RP) films, various concentrations of plasticizers and emulsifiers were incorporated into the preparation of a film-forming solution. The optimal conditions for the preparation of the RP film were 2% sorbitol/0.5% sucrose as plasticizer and 1.5% polysorbate 20 as an emulsifier. In addition, RP blend films were prepared. Gelidium corneum or gelatin was added to improve the physical properties of the RP film, and the highest tensile strength value of the films was 53.45 MPa for the 3% RP/4% gelatin film. Our results suggest that the RP-gelatin blend film is suitable for applications in food packaging. Edible RP films prepared in the present investigation can be applied in food packaging.

Synthesis of poly(3-hydroxybutyrate) nanospheres and deposition thereof into porous thin film

NASA Astrophysics Data System (ADS)

Abid, S.; Raza, Z. A.; Rehman, A.

2016-10-01

Polymeric nanostructures have gained importance in medical science as drug delivery carriers due to their biocompatibility and biodegradability. Polyhydroxybutyrate (PHB) is one of the natural biodegradable polymers used to deliver drugs in the form of nano/microcapsules. In this study, solvent evaporation method has been used for the synthesis of PHB nanospheres using poly(vinyl) alcohol (PVA) both as emulsifier and stabilizer. The produced PHB nanospheres were analyzed using dynamic light scattering and scanning electron microscopy. The size of nanospheres decreased whereas the zeta potential increased on increasing the concentration of emulsifier. The PHB nanospheres were then deposited into porous thin film on a glass surface and characterized against bulk PHB film by using atomic force microscopy, contact angle measurement and x-ray diffraction.

Distinct Mechanisms of Ferritin Delivery to Lysosomes in Iron-Depleted and Iron-Replete Cells ▿

PubMed Central

Asano, Takeshi; Komatsu, Masaaki; Yamaguchi-Iwai, Yuko; Ishikawa, Fuyuki; Mizushima, Noboru; Iwai, Kazuhiro

2011-01-01

Ferritin is a cytosolic protein that stores excess iron, thereby protecting cells from iron toxicity. Ferritin-stored iron is believed to be utilized when cells become iron deficient; however, the mechanisms underlying the extraction of iron from ferritin have yet to be fully elucidated. Here, we demonstrate that ferritin is degraded in the lysosome under iron-depleted conditions and that the acidic environment of the lysosome is crucial for iron extraction from ferritin and utilization by cells. Ferritin was targeted for degradation in the lysosome even under iron-replete conditions in primary cells; however, the mechanisms underlying lysosomal targeting of ferritin were distinct under depleted and replete conditions. In iron-depleted cells, ferritin was targeted to the lysosome via a mechanism that involved autophagy. In contrast, lysosomal targeting of ferritin in iron-replete cells did not involve autophagy. The autophagy-independent pathway of ferritin delivery to lysosomes was deficient in several cancer-derived cells, and cancer-derived cell lines are more resistant to iron toxicity than primary cells. Collectively, these results suggest that ferritin trafficking may be differentially regulated by cell type and that loss of ferritin delivery to the lysosome under iron-replete conditions may be related to oncogenic cellular transformation. PMID:21444722

Iron acquisition by Haemophilus influenzae.

PubMed Central

Pidcock, K A; Wooten, J A; Daley, B A; Stull, T L

1988-01-01

The mechanisms for acquisition of iron by Haemophilus influenzae and their role in pathogenesis are not known. Heme and nonheme sources of iron were evaluated for their effect on growth of type b and nontypable strains of H. influenzae in an iron-restricted, defined medium. All 13 strains acquired iron from heme, hemoglobin, hemoglobin-haptoglobin, and heme-hemopexin. Among nonheme sources of protein-bound iron, growth of H. influenzae was enhanced by partially saturated human transferrin but not by lactoferrin or ferritin. Purified ferrienterochelin and ferridesferrioxamine failed to provide iron to H. influenzae, and the supernatants of H. influenzae E1a grown in iron-restricted medium failed to enhance iron-restricted growth of siderophore-dependent strains of Escherichia coli, Salmonella typhimurium, and Arthrobacter terregens. Marked alterations in the profile of outer membrane proteins of H. influenzae were observed when the level of free iron was varied between 1 microM and 1 mM. Catechols were not detected in the supernatants of strain E1a; however, iron-related hydroxamate production was detected by two biochemical assays. We conclude that the sources of iron for H. influenzae are diverse. The significance of hydroxamate production and iron-related outer membrane proteins to H. influenzae iron acquisition is not yet clear. Images PMID:2964410