Presence Of Sodium Tripolyphosphate Research Articles

Potential of ADAM 17 Signal Peptide To Form Amyloid Aggregates in Vitro.

ADAM 17, a disintegrin and metalloproteinase 17 belonging to the adamalysin protein family, is a Zn2+-dependent type-I transmembrane α-secretase protein. As a major sheddase, ADAM 17 acts as an indispensable regulator of chief cellular events and controls diverse cytokines, adhesion molecules, and growth factors. The signal peptide (residues 1-17) of ADAM 17 targets the protein to the secretory pathway and gets cleaved off afterward. No other function is documented for the ADAM 17 signal peptide (ADAM 17-SP) inside the cells. Here, we have taken a reductionist approach to understand the biophysical properties of ADAM 17-SP. Aiming to understand the possibility of aggregation, we found several aggregation-prone segments in the signal peptide. We performed in vitro experiments to show that the signal peptide forms amyloid-like aggregates in buffered conditions. We also studied its aggregation in the presence of sodium tripolyphosphate and heparin to correlate with the cellular conditions, as these biomolecules are naturally present inside cells. Further, we performed seeding experiments to observe the possibility of ADAM 17-SP aggregate interaction with the Aβ42 peptide. The results suggest that its seeds escalate the aggregation kinetics of the Aβ42 peptide and form heteromeric aggregates with it. We believe this finding could further intensify the aggregation studies on other signal peptides and shed light on the potential role of these segments other than signaling.

Multi-spectroscopies and molecular simulation insights into the binding of bovine serum albumin and sodium tripolyphosphate

Sodium tripolyphosphate (STPP) is an odorless and water-soluble anionic mineral compound. STPP is used as a separator, texturizer, emulsifier and buffer in the food and detergent industries. Considering the importance of the topic and the interaction of food additives with biological molecules including blood serum albumin, we investigated the binding properties of STPP food additive to blood serum albumin through UV–Vis spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and molecular docking analysis. According to the results, after forming a complex with BSA, STPP reduced the fluorescence intensity of BSA through static quenching mechanisms, and the UV–Vis absorption results were also confirmatory. Synchronous fluorescence and FT-IR results showed that the microenvironment and secondary structure of BSA changed in the presence of STPP. The synchronous fluorescence study has shown that the quenching toward Trp residue is higher than Tyr residue. The thermodynamic results showed that van der Waals force and hydrogen bonding play the main roles in the formation of the STPP-BSA complex. The binding constant decreases from 2.23 × 106 to 4.25 × 101 (M−1) with increasing temperature, indicating a decrease in complex formation due to the interaction of STPP with BSA. Furthermore, molecular docking studies showed that STPP binds to the cavity between domains IIIA and IIIB by van der Waals forces and hydrogen bonds through residues Ser 418, Thr 419, Tyr 496, Lys 499, and Lys 533.

Preparation of mucoadhesive methacrylated chitosan nanoparticles for delivery of ciprofloxacin

Mucoadhesive polymers and their nanoparticles have attracted a lot of attention in pharmaceutical applications, especially transmucosal drug delivery (TDD). Mucoadhesive polysaccharide-based nanoparticles, particularly chitosan, and its derivatives, are widely used for TDD owing to their outstanding features such as biocompatibility, mucoadhesive, and absorption-enhancing properties. Herein, this study aimed to design potential mucoadhesive nanoparticles for the delivery of ciprofloxacin based on methacrylated chitosan (MeCHI) using the ionic gelation method in the presence of sodium tripolyphosphate (TPP) and compared them with the unmodified chitosan nanoparticles. In this study, different experimental conditions including the polymer to TPP mass ratios, NaCl, and TPP concentration were changed to achieve unmodified and MeCHI nanoparticles with the smallest particle size and lowest polydispersity index. At 4:1 polymer /TPP mass ratio, both chitosan and MeCHI nanoparticles had the smallest size (133 ± 5 nm and 206 ± 9 nm, respectively). MeCHI nanoparticles were generally larger and slightly more polydisperse than the unmodified chitosan nanoparticles. Ciprofloxacin-loaded MeCHI nanoparticles had the highest encapsulation efficiency (69 ± 13 %) at 4:1 MeCHI /TPP mass ratio and 0.5 mg/mL TPP, but similar encapsulation efficiency to that of their chitosan counterpart at 1 mg/mL TPP. They also provided a more sustained and slower drug release compared to their chitosan counterpart. Additionally, the mucoadhesion (retention) study on sheep abomasum mucosa showed that ciprofloxacin-loaded MeCHI nanoparticles with optimized TPP concentration had better retention than the unmodified chitosan counterpart. The percentage of the remained ciprofloxacin-loaded MeCHI and chitosan nanoparticles on the mucosal surface was 96 % and 88 %, respectively. Therefore, MeCHI nanoparticles have an excellent potential for applications in drug delivery.

The underlying role of sodium tripolyphosphate on the cementitious mechanism of calcium carbonate binder

Calcium carbonate binder is well-known to reduce the carbon footprint and brings great economic and environmental benefits. However, the cementitious mechanism is unclear due to raw material diversity. We prepare calcium carbonate crystalline polymorphs-vaterite and calcite in the presence of sodium tripolyphosphate (STPP), and the cementitious mechanism is revealed. Herein, the optimal colloidal structure with vaterite as the binding phase is obtained at 5% STPP and the 1d compressive strength reaches 16.99 MPa. The cementitious property can be attributed to the crystallization transformation of amorphous calcium carbonate (ACC) and the electrostatic attraction of particles. In the cementitious process, the effect of STPP on the polymorph selection is determined by STPP contents. At low contents (＜5%), STPP is more effective in inhibiting the nucleation and growth of calcite than vaterite. At high contents (＞5%), calcite is entirely inhibited while the formation of vaterite takes place on the surface of bulk ACC through the coupling mechanism of dissolution-recrystallization and solid-state growth. These results shed light on the function of STPP during calcium carbonate biomineralization and the cementitious mechanism can help for preparing low-carbon calcium carbonate binder.

Structural, gelatinization, and rheological properties of heat-moisture treated potato starch with added salt and its application in potato starch noodles

Gluten-free noodles, e.g. potato starch noodles, are getting popular due to the increasing population with gluten sensitivity and celiac disease. However, due to the lack of gluten network, the solid loss of potato starch noodles during cooking leads to lower textural and sensory attributes. The starch modification provides the opportunity to address these shortcomings. Here, we report the application of heat-moisture treated (HMT) potato starch with added salt as a binder to improve the cooking and textural properties of potato starch noodles. In the presence of sodium tripolyphosphate (STPP) and sodium chloride (SC), starch granules exhibited irregular shapes and deformed crystalline growth rings, agglomerated due to partial gelatinization, and lost double-helical structures and the perfection of crystallites after being subjected to HMT. As affected by the starch-ions interactions and changed water structure, HMT-modified starch with added SC and STPP had higher pasting temperatures, less amylose leaching, and lower gelatinization enthalpies and pasting viscosities than HMT starch without salts. Meanwhile, higher cross-over temperatures and lower G’ values were found in HMT starch with added STPP and SC compared to HMT starch. Iodine-staining micrographs also confirmed the delay in the disintegrating process of starch granules in HMT-modified starch with added SC and STPP. Furthermore, when HMT-modified starch with added SC was applied as binder paste, starch dough owned higher hardness and starch noodles exhibited less solid loss and broken noodles, firmer texture, and better elasticity. The results thus provide the opportunity to improve the textural attributes of potato starch noodles with the application of HMT potato starch and salt as the binder. • Structural changes of starch before and after HMT as affected by salts are studied. • Adding sodium chloride induces the losses of ordered structure of starch during HMT. • Adding salts delays the disintegrating of starch granules during gelatinization. • HMT starch with added sodium chloride (HPS-SC) has better heat and shear stability. • HPS-SC as a binder improves cooking performance and texture of starch noodles.

Upconversion photoluminescent Yb(Ⅲ)/Er(Ⅲ) doped nanoparticles interact with AuNPs for detection of Cr (Ⅲ) and sodium tripolyphosphate based on FRET

In this study, we designed a dual functional nanosensor for detecting Cr (Ⅲ) and sodium tripolyphosphate (STPP) based on fluorescence resonance energy transfer (FRET) mechanism between amine functionalized upconversion nanoparticles (UCNPs) and gold nanoparticles (AuNPs), where UCNPs serve as energy donor and aggregated AuNPs as energy acceptor. UCNPs have red emission at 654 nm under 980 nm laser excitation and monodispersed AuNPs show strong absorbance around 520 nm. Monodispersed AuNPs form aggregate easily in the presence of Cr (Ⅲ), which leads to the red-shift of the absorption of AuNPs and quenches the red emission of UCNPs. In the presence of STPP, the formation of Cr (Ⅲ)-STPP complex weakens the aggregation extent of AuNPs and the red emission of UCNPs increases. Therefore, the content of Cr (Ⅲ) and STPP could be detected in wide range according to the linear variety of fluorescence intensities of UCNPs at 654 nm with the detection limits of 0.44 μM and 0.54 μM for detecting Cr (Ⅲ) and STPP, respectively. In addition, due to the high selectivity and accuracy for the detection of STPP, this nanosensor can be utilized to determine STPP in green tea drink and drinking water.

Solubility and emulsifying properties of perilla protein isolate: Improvement by phosphorylation in the presence of sodium tripolyphosphate and sodium trimetaphosphate

To investigate the mechanisms of phosphates affecting the solubility and emulsifying properties of perilla protein isolate (PPI), PPI was treated with sodium trimetaphosphate (STMP) and sodium tripolyphosphate (STPP) at different concentrations. FTIR and XPS showed that phosphate groups were bonded to PPI through COP bonds. The introduction of STPP increased the particle size and electronegativity of PPI, resulting in the exposure of hydrophobic groups and free -SH groups, as well as the changes of secondary structure and tertiary conformation. All these variations induced increased oil holding capacity, thermal stability, solubility, emulsifying and foaming properties of PPI, especially at STPP concentration of 8%. Furthermore, o/w emulsions stabilized by STPP-modified PPI exhibited higher stability, which could be attributed to the higher interfacial adsorption protein amount and smaller droplet size. These results indicated that PPI modified by phosphate (especially STPP) can be used in the construction of food-grade emulsion systems.

Chitosan Polymeric Nanoparticles as a Carrier of <i>Thymbra spicata</i> Hydroalcoholic Extract: Effect on Growth Parameters in Rainbow Trout (<i>Oncorhynchus mykiss</i>)

This study aimed to investigate the effect of using chitosan polymeric nanoparticles (CNPs) on improving the efficiency of hydroalcoholic extract of Thymbra spicata (TS) on the growth parameters of rainbow trout (Oncorhynchus mykiss) fed with the experimental diets containing different levels of TS extract with and without CNPs. Thymbra spicata loaded chitosan polymeric nanoparticles (TSCNPs) were prepared by ionic gelation methods in the presence of sodium tripolyphosphate (TPP). The fourier transform infrared spectroscopy (FT-IR) of TSCNPs showed that the strong peaks due to hydroxyl groups (OH) and alcohol and amine (NH) were shifted to 3427 cm−1, and peak wide has expanded due to increased hydrogen bonds. The FT-IR results were proved the interaction of CNPs and TS extract. The scanning electron microscope (SEM) imaging showed a spherical shape, smooth and homogeneous structure for nanoparticles. In zetasizer results, nanoparticles size average, poly dispersity index (PDI), zeta potential (ZP), and zeta average (d.nm) were 86.1 nm, 0.21, 31.3 mV, and 83.3, respectively. In energy dispersive spectroscopy (EDS) results, the major compounds of TSCNPs included C, O, Al, Cl, Mg, K, and Ca. At the UV-Visible spectrum, the absorption of TS extract based on the absorption of flavonoids was observed at 430 nm. Obtained results showed that the encapsulation efficiency (EE) of the nanoparticles was 94.1%. In vitro, a gradual and acidic dependent period of 120 h was observed in TS release conditions. After eight weeks of feeding, the addition of 400 mg kg-1 diet of TSCNPs resulted in significant improvement in the final weight, final length, specific growth rate (SGR), and survival (S) (P < 0.05). This research suggests that loading Thymbra spicata hydroalcoholic extracts on chitosan polymeric nanoparticles increased the efficiency of plant extract compared to extract pure form and improved the growth performance in rainbow trout.

Assessment of Exenatide loaded Biotinylated Trimethylated Chitosan/HP- 55 Nanoparticles.

Exenatide(EXE) is an anti-hyperglycemic agent approved for treating type 2 diabetes by the Food and Drug Administration(FDA). However, twice-daily injection of exenatide is inconvenient for most of the patients. In this study, biotinylated trimethylated chitosan(Bio-TMC) based nanoparticles were proposed to promote oral absorption of exenatide. Realizing the oral administration of exenatide is very important to alleviate patient suffering and improve patient compliance. Bio-TMC was synthesized, and the chemical structure was characterized by Fourier transform infrared (FT-IR) spectroscopy and 1H NMR spectroscopy. Nanoparticles were prepared through polyelectrolyte interaction in the presence of sodium Tripolyphosphate (TPP) and hydroxypropyl methylcellulose phthalate (HP-55). Formulations were physically and chemically characterized. In vitro release was investigated in different pH media. In vivo antidiabetic activities of biotin modified and non-biotin modified chitosan were evaluated in db/db mice. EXE-loaded Bio-TMC/HP-55 nanoparticles were spherical in shape with a mean diameter of 156.2 nm and zeta potential of +11.3 mV. The drug loading efficiency and loading content were 52.38% and 2.08%, respectively. In vitro release revealed that EXE-loaded Bio-TMC/HP-55 nanoparticles were released faster in pH 1.2 than pH 6.8 (63.71% VS 50.12%), indicating that nanoparticles have enteric characteristics. Antidiabetic activity study revealed that after oral administration to diabetic mice, the relative pharmacological bioavailability (FPharm%) of the biotin modified nanoparticles was found to be 1.27-fold higher compared to the unmodified ones, and the hypoglycemic effect was also found to be better. Bio-TMC/HP-55 nanoparticles are feasible as oral drug carriers of exenatide and have the potential to be extended to other drugs that are not readily oral, such as monoclonal antibodies, vaccines, genes, etc. These would be beneficial to the pharmaceutical industry. Further research will focus on the biodistribution of Bio-TMC/HP-55 nanoparticles after oral administration.

Postharvest Physicochemical Properties and Fungal Populations of Treated Cucumber with Sodium Tripolyphosphate/Titanium Dioxide Nanoparticles during Storage

Cucumbers have a limited shelf-life, from 10 to 14 days at commercial temperatures with relative humidity (80%). The aim of the work was to evaluate the postharvest physicochemical properties and fungal populations of cucumber treated with sodium tripolyphosphate/titanium dioxide nanoparticles during storage at 10 °C to prolong the shelf-life to 21 days. Cucumber samples treated with chitosan/sodium tripolyphosphate/titanium dioxide nanoparticles (Cu-CHS-TDN-ST) and (Cu-CHS-TDN-ST) were found to be in a well-hydrated state and with a green-colored appearance upon day 21, with excellent quality for consumption. Chitosan coating (Cu-CHS) alone prolonged the cucumber shelf-life for 14 days of storage. The Cu-CHS coating was less evident in reducing the respiration rate of cucumbers on day 14 than both nanocoatings, which were reported at the end of the storage period to be 5.09 and 5.38 mg·kg−1 h−1 for Cu-CHS-TDN-ST and Cu-CHS-TDN, respectively. The Cu-CHS-TDN-ST treatment reduced the loss of ascorbic acid content to 13.17 mg/100 g, delayed chilling injury, and had the highest chlorophyll contents during the whole storage period. The presence of sodium tripolyphosphate with the nanocoating delayed tissue damage. Peroxidase enzyme activity reached the maximum of 54.65 Ug−1 for Cu-CHS-TDN-ST on day 21, followed by Cu-CHS-TDN 50.1 Ug−1. On day 21, the fungal populations of Cu-CHS-TDN samples (3.77 log CFU/g) were more than that of Cu-CHS-TDN-ST (3.15 log CFU/g) against Cu-Control (100 % spoiled). It was noted that the Cu-CHS-TDN-ST and CHS-TDN-ST coating treatments were capable of preserving the cucumber samples’ quality during storage. The addition of sodium tripolyphosphate as a crosslinker for stabilizing the nanoparticle polymers in the coating treatments prolonged the shelf-life and achieved excellent quality for the cucumbers.

New chitosan derivatives inspired on heterocyclic anhydride of potential bioactive for medical applications

In the present work new chitosan derivatives inspired heterocyclic anhydride were prepared to improve the biological activities of chitosan via imidization reaction of chitosan (CS) and N-(1,3-dioxoisoindolin-2-yl)-1,3-dioxo-1,3-dihydroiso-benzofuran-5-carboxamide (5) to yield amic acid CS-6 at room temperature and imide CS-8 thermally. However, the reaction between (CS) and anhydride (5) in presence of sodium tripolyphosphate (TPP) or Poly (ethylene glycol) diglycidyl ether (PEGDG) at room temperature yielded CS-6 NPs and CS-7 respectively. The structure of new chitosan derivatives was characterized using morphological and spectroscopic analyses. From evaluation of the biological activities, the greatest enzymatic inhibitory for trypsin and α-chymotrypsin revealed by CS-7 at 88.33 ± 2.27 and 79.63 ± 3.16% respectively. Furthermore, the highest inhibition zones, (MIC) and (MBC) against S. aureus and B. subtilis recorded by CS-6 NPs at 21 ± 0.75, 22 ± 0.98 mm, 19.5, 19.5, 38 and 38 ppm respectively. Additionally, CS-8 displayed the best cell growth inhibition against vero cell line at 93.17 ± 0.29%.

Changes in stability and in vitro digestion of egg-protein stabilized emulsions and β-carotene gels in the presence of sodium tripolyphosphate.

Egg proteins are effective emulsifiers and gelators in food systems. However, the physicochemical stability and control release properties of egg-protein stabilized emulsions and gels need to be further improved. The potential of sodium tripolyphosphate (St) to improve the functionality of egg proteins was evaluated. The emulsions with St had smaller particle sizes and higher zeta potential, leading to better physical stability. Furthermore, the oxidation stability increased with increasing St contents, possibly due to its metal chelating capacity and the improved emulsifying activity of whole-egg dispersions. Phosphate had a positive impact on the chemical stability of β-carotene in whole-egg liquids and gels, decreasing the degradation during thermal treatment. The gel made with St was firm and broke down slowly, leading to a low rate of digestion and β-carotene release in simulated gastric fluid. This study shows that St is useful to improve the egg proteins stabilized emulsions and gels, which is applicable in the development of emulsion-based food grade gel products. © 2021 Society of Chemical Industry.

Evaluation of Calcium Binding Capacity of Chelating Agents in Calcium Carbonate Suspension and Effects on Calcium Distribution of Calcium Chelating Agents

In this study, the binding capacity of calcium ions of sodium tripolyphosphate (STPP), tetrasodium pyrophosphate (TSPP), trisodium citrate (TSC), and potassium oxalate (PO) were evaluated, and the calcium distribution in the presence of STPP and TSPP in CaCl2 solutions (50 mmol L−1) were investigated. Under conditions simulating industrial toothpaste, the concentration of fluoride in calcium carbonate suspensions (30 g/50 g) was measured by ion chromatography to investigate the effects of chelating agents on calcium ions. Among all the chelating agents, STPP and TSPP have the highest retention rate of fluoride, indicating better calcium binding capacity. Preliminary studies were carried out in CaCl2 solutions to investigate the influence of concentration and pH on the chelating performance of STPP and TSPP. The distribution of free calcium, chelated calcium, and precipitated calcium in CaCl2 solution in the presence of STPP and TSPP were investigated to reveal two different calcium-chelation mechanisms and laws for STPP and TSPP. This work has a positive guiding significance for the stabilisation of calcium and fluoride in toothpaste formula.

Sodium tripolyphosphate as a selective depressant for separating magnesite from dolomite and its depression mechanism

Efficient separation of magnesite from dolomite remains challenging owing to the similar floatability of the two minerals. Therefore, understanding the adsorption behaviors of surfactants (depressants and collectors) on their surfaces is essential for improving separation efficiency. In this study, the ability of sodium tripolyphosphate (STPP) to separate magnesite from dolomite was evaluated in sodium oleate (NaOl) systems, with an emphasis on its effect on the depression of dolomite. The mechanisms underlying the differential adsorption and depression of STPP were investigated through surface analyses, namely Fourier transform infrared spectroscopy, zeta-potential analysis, adsorption-quantity analysis, and X-ray photoelectron spectroscopy. The flotation results indicated that STPP facilitated the removal of dolomite from magnesite in the NaOl system because it significantly depressed dolomite, whereas its effect on magnesite was negligible. Surface analyses revealed that the preferential adsorption of STPP on dolomite was due to the interaction between the –PO4 tetrahedra of STPP and Ca sites. Furthermore, in the presence of STPP, small amounts of NaOl were adsorbed onto dolomite, inhibiting the flotation of dolomite. However, substantial amounts of NaOl were adsorbed onto magnesite, maintaining the good floatability of magnesite. Therefore, STPP can be considered as a promising depressant for separating magnesite from dolomite via direct flotation.

Development of Meloxicam-chitosan magnetic nanoconjugates for targeting rheumatoid arthritis joints: Pharmaceutical characterization and preclinical assessment on murine models

The primary aim of our study is to formulate the meloxicam loaded chitosan-magnetite nanoconjugates (MC-MNCs) for the magnetically targeted rheumatoid arthritis therapy with an anticipation to improve the drug efficacy through enhancing its regional bioavailability, reducing dose frequency and related toxicity. The chitosan-magnetite nanoconjugates was prepared by in-situ co-precipitation of FeSO4 and FeCl3 solution in basic medium subsequently cross-linked with chitosan in the presence of sodium tripolyphosphate. Meloxicam dispersion was co-loaded onto the chitosan-magnetite nanoconjugates yielding MC-MNCs. These nanoconjugates were characterized by diverse techniques for their morphological, physicochemical, magnetic, pharmaceutical and pharmacological properties. MC-MNCs were roughly spherical. DLS measurements confirm its mean hydrodynamic size (258 nm), polydispersity index (0.233) and zeta potential (25.6 mV). FT-IR spectroscopic investigations showed the functional integrity of meloxicam, while XRD measurements showed the crystalline nature of magnetite and meloxicam in MC-MNCs, respectively. The chitosan-coated magnetite nanoparticles (C-MNP) and MC-MNCs showed a magnetic susceptibility of 168 × 10-5 and 110 × 10-5 SI units, respectively. The encapsulation efficiency and loading capacity of meloxicam entrapped into MC-MNCs was found to be 82% and 13% respectively. Thein-vitromeloxicam release in phosphate buffer saline (pH 7.4) showed an initial burst release effect and followed by a slow drug release pattern. Meloxicam release from the MC-MNCs followed the Michaelis-Menten kinetics, adopting a super case II transport mechanism. MC-MNCs was found sufficiently stable with no major visual changes. Murine models of inflammation and arthritis was used to test the pharmacological efficacy of MC-MNCs. Magnetically targeted drug delivery of MC-MNCs enhanced the anti-inflammatory effect and anti-arthritic activity on the carrageenan-induced paw oedema in adjuvant-induced arthritis models in rats when compared with other treatments without applied magnetic field. Considering the overall research analysis, it is concluded that the MC-MNCs could be used as a viable alternative to the conventional formulations of meloxicam to ease rheumatoid arthritis.

Facile Synthesis of (E)-5-Styrylpyrimidines via Wittig Reaction Using So-dium Tripolyphosphate in Water

Abstract: An inexpensive and eco-friendly Wittig olefination protocol has been developed to prepare novel (E)-5-styrylpy-rimidines. The reaction of pyrimidine phosphonium ylide with different aryl/hetero-aryl aldehydes underwent smoothly in the presence of sodium tripolyphosphate (STPP) in aqueous condition giving (E)-5-styrylpyrimidines (10a-t) in very high yields (77-96 %).

Calcium ion mediated rapid wound healing by nano-ZnO doped calcium phosphate-chitosan-alginate biocomposites

We report a facile technique to prepare biocomposite dressing material using interpolymeric complexation of fibrous chitosan-alginate condensed with calcium phosphate (CaP-NPs) and zinc oxide (ZnO-NPs) nanoparticles to attain the cell proliferation, antibacterial activity and, enhance wound healing. The biocomposite was prepared by the solvent casting method after mixing the nanoparticles with chitosan and sodium alginate within the presence of sodium tri-polyphosphate as a crosslinking agent. CaP-NPs and ZnO-NPs were synthesized by the co-precipitation method and characterized by TEM and XRD. The crystallite size of the nanoparticles was found 73 and 44 nm respectively by XRD. It had been observed that, about 61% of Ca2+ ions was released from the prepared biocomposites in PBS at pH 5.5 with extremely enhanced swelling (about 431%). Among two bacterial strain E. coli and S.enterica, E. coli showed higher zone of inhibition area. The biocompatibility testing of the biocomposite through with Vero and BHK-21 fibroblast cells indicated no toxicity to mammalian cells, and cell culture of BHK-21 showed a significant increase in cell density. The wound healing efficiency of the biocomposite was assessed in experimental full-thickness wounds utilizing a mice model, demonstrated that inside 10 days the wound was loaded up with new epithelium with no significant unfavorable impacts, though just 30% closure was found for ordinary bandage dressing. The in vivo results revealed that calcium phosphate-chitosan-alginate biocomposite may be a promising contender for CaP-NPs prompted rapid wound closure applications.

Modulating the structure of organofunctionalized hydroxyapatite/tripolyphosphate/chitosan spheres for dye removal

• The preparation and characterization of amino hydroxyapatite/sodium tripolyphosphate/chitosan spheres are described. • Different proportions (10% to 75%) of organofunctionalized hydroxyapatite were employed. • The organofunctionalized HA samples presented high efficiency for dye removal. • Low toxicity of the prepared spheres was observed. Hybrid materials based on amino hydroxyapatite (NH 2 -HA) and chitosan (CS) were prepared by reticulation in the presence of sodium tripolyphosphate. NH 2 -HA having different weight percentages (10–75%) was used in the synthesis. The resulting solids were used for the removal of reactive violet 5R—an organic dye—from an aqueous solution. The synergy among the adsorptive properties of the precursors was assessed for the hybrid biomaterials by X-ray diffraction, thermogravimetry, CHN elemental analysis, infrared spectroscopy, and 13 C nuclear magnetic resonance spectroscopy. The crosslinking mechanism was also elucidated. The effects of adsorbent dosage, time, pH, and initial dye concentration were investigated. The adsorption capacities of the resulting hybrids were proportional to the CS content in the hybrids and the surfaces were positively charged at pH 1–7. The optimal dye-removal capacity of 350 and 365 mg g -1 was achieved at pH 3 for the solids containing 10 and 25% silylated HA, respectively. Kinetic data were evaluated for the pseudo-first-order, pseudo-second-order, and Elovich models. At equilibrium, various systems were adjusted to the Langmuir models. The amino groups were blocked via the reaction with acetyl chloride, which demonstrated the contribution of different active sites in the prepared hybrids toward dye removal. The Artemia salina tests demonstrated the low toxicity of the prepared hybrids irrespective of their composition. The data indicated that the prepared hybrids were capable of achieving rapid and high dye removal. Additionally, the reuse tests suggested the formation of stable-loaded-dye substrates after adsorption.

Interfacial and enhanced emulsifying behavior of phosphorylated ovalbumin.

Improvement of emulsifying properties by phosphorylation could have a wide potential application in food industry. In this study, ovalbumin (OVA) was phosphorylated under wet-heating in the presence of sodium tripolyphosphate. Phosphorylated OVA (P-OVA) with low, middle, high phosphorus content were obtained with reaction time increased. Their enhanced emulsification capacity and the mechanism were investigated. Compared with native OVA (N-OVA), the emulsifying activity and stability of P-OVA were increased by 26% and 109% (P < 0.05), respectively. The structure studies (Fourier transform infrared spectroscopy, circular dichroism spectra, scanning electron microscope) demonstrated that introduction of phosphate groups to OVA increased the molecular flexibility of P-OVA. The absolute values of surface zeta-potential and surface hydrophobicity were increased as the phosphorus content increased, which indicated that the phosphate group inhibited protein aggregation. And it caused a large amount absorption of protein on the surface of the oil droplets, which ultimately improved the emulsion stability. Both particle size and microscopic results of emulsion showed that the particle size of OVA reduced as the degree of phosphorylation increased, which improved the emulsifying ability.

Consequences of phosphorylation on the structural and foaming properties of ovalbumin under wet-heating conditions

In this study, ovalbumin (OVA) was phosphorylated under wet-heating in the presence of sodium tripolyphosphate at pH 6.0 and 60 °C for 1, 2, 3, 4 and 5 h, and the structural and physical properties of phosphorylated OVA (P-OVA) were investigated. The FT-IR spectrum confirmed the covalent attachment of the phosphate group to OVA. New possible phosphate sites (Ser-221, Ser-269, Tyr-281 and Ser-324) were detected by using liquid chromatography in tandem with mass spectrometry. Circular dichroism (CD) spectra demonstrated that P-OVA molecular became more flexible and disordered. The decreased fluorescence intensity indicated that the chromophore microenvironment became more exposed and polar because of conformational changes. The surface hydrophobicity (H0) and the absolute value of zeta potential of P-OVA obtained at 5 h was 1.8 and 1.5 times higher than that of N-OVA. Foaming ability (FA) and foaming stability (FS) were enhanced by 1.7 and 4.4 times after wet-heating phosphorylation for 4 h, which were up to 87.0% and 28.5%, respectively. Furthermore, the correlation analysis suggested that FA was significantly correlated to random structure (P < 0.01) and H0 (P < 0.01), and zeta potential was related with FS (P < 0.05).