Antimicrobial Activity and Degradation of Superhydrophobic Magnesium Substrates in Bacterial Media

The interest in magnesium-based materials is promoted by their biocompatibility, their bioresorbability, and their recently discovered antibacterial potential. Until now, the widespread use of magnesium alloys in different corrosive environments was inhibited by their weakly controllable degradation rate and poorly understood microbiologically induced corrosion behavior. To better understand the degradation and usability of magnesium-based alloys, in this study we have fabricated superhydrophobic coatings on a magnesium-based alloy, and analyzed the behavior of this alloy in bacterial dispersions of Pseudomonas aeruginosa and Klebsiella pneumoniae cells in phosphate-buffered saline. It was shown that the immersion of such coatings in bacterial dispersions causes notable changes in the morphology of the samples, dependent on the bacterial dispersion composition and the type of bacterial strain. The interaction of the superhydrophobic coatings with the bacterial dispersion caused the formation of biofilms and sodium polyphosphate films, which provided enhanced barrier properties in magnesium dissolution and hence in dispersion medium alkalization, eventually leading to the inhibition of magnesium substrate degradation. The electrochemical data obtained for superhydrophobic samples in continuous contact with corrosive bacterial dispersions for 48 h indicated a high level of anticorrosion protection.

Industrial and culinary practice effects on biologically active polyamines level in turkey meat

Polyamines, including putrescine, spermidine, and spermine, are biological compounds present in nearly all food items. Their desirable physiological effects include cell division and growth. Hence, are undesirable in the diet of patients with tumor. This study aimed to assess the impact of curing agents (sodium chloride (0–2 g), sodium nitrite (0–200 ppm), sodium polyphosphate (0–0.5 g), and ascorbic acid (0–500 ppm)), cooking (frying (180°C), and boiling (100°C)) on polyamine contents in turkey breast meat using response surface methodology based on central composite design and dispersive liquid-liquid microextraction. Postprocessing changes were investigated using a high-performance liquid chromatography equipped with an ultraviolet detector. Study outcomes showed the presence of sodium chloride, sodium nitrite, and sodium polyphosphate in turkey meat reduced the putrescine and spermine content significantly (P < 0.0001). The addition of ascorbic acid as a curing agent slightly increased the concentration of polyamines, while no significant linear effects were associated with the thermal processes. The study observed that curing agents like sodium chloride, sodium nitrite, sodium polyphosphate, and ascorbic acid at 2 g, 200 ppm, 0.5 g, and 382 ppm, respectively, in frying mode minimized spermine and putrescine content with more than 96% desirability. In conclusion, curing additives and cooking are promising procedures for polyamine reduction in turkey breast meat.

Antimicrobial activity and degradation of superhydrophobic magnesium substrates in bacterial media

The interest in magnesium-based materials is promoted by their biocompatibility, bioresorbability, and by their recently found antibacterial potential. Until now the widespread use of magnesium alloys in different corrosive environments was inhibited by their weakly controllable degradation rate and poorly understood microbiologically induced corrosion behavior. To better understand the degradation and usability of magnesium-based alloys, in this study we have fabricated the superhydrophobic coatings on top of magnesium-based alloy and analyzed the behavior of this alloy in bacterial dispersions of Pseudomonas aeruginosa and Klebsiella pneumoniae cells in phosphate buffered saline. It was shown that immersion of such coatings into bacterial dispersions causes notable changes in the morphology of the samples, dependent on the bacterial dispersion composition and the type of bacterial strain. The interaction of superhydrophobic coatings with the bacterial dispersion caused the formation of biofilms and sodium polyphosphate films, which provided enhanced barrier properties for magnesium dissolution and hence for dispersion medium alkalization, eventually leading to inhibition of magnesium substrate degradation. Electrochemical data obtained for superhydrophobic samples continuously contacted with the corrosive bacterial dispersions during 48 h indicated a high level of anti-corrosion protection.

Ionic conductivity and dielectric properties of bulk SPP-PEG hydrogel as Na+ ion based SPE material for energy storage applications

Green SPP-PEG hydrogel material, containing Na+ ions, has been synthesized by green chemistry methodology using sodium polyphosphate and polyethylene glycol in water. Hydrogel has amorphous morphology and sandwiched matrix with...

Minocycline-loaded calcium polyphosphate glass microspheres as a potential drug-delivery agent for the treatment of periodontitis

Background: Periodontitis is an inflammatory disease with a bacterial etiology that affects the supporting structures of the teeth and is a major cause of tooth loss. The objective of this study was to investigate the drug loading and in vitro release of minocycline from novel calcium polyphosphate microspheres intended for use in treating periodontitis. Methods: Calcium polyphosphate coacervate, produced by a precipitation reaction of calcium chloride and sodium polyphosphate solutions, was loaded with minocycline and subsequently used to produce microspheres by an emulsion/solvent extraction technique. Microspheres classified by size were subjected to a 7-day elution in a Tris-buffer solution under dynamic conditions. The physicochemical characteristics of the drug-loaded microspheres were investigated using scanning electron microscopy, particle size analysis, Phosphorus-31 Nuclear Magnetic Resonance spectroscopy, and Inductively Coupled Plasma Optical Emission Spectroscopy. Drug loading and release were determined using ultraviolet -visible (UV/VIS) spectrophotometry. Results: Minocycline-loaded calcium polyphosphate microspheres of varying size were successfully produced, with small and large microspheres having volume mean diameters of 22 ± 1 µm and 193 ± 5 µm, respectively. Polyphosphate chain length and calcium to phosphorus mole ratio remained stable throughout microsphere production. Drug loading was 1.64 ± 0.16, 1.35 ± 0.55, and 0.84 ± 0.14 weight% for the coacervate and large and small microspheres, respectively, corresponding to mean encapsulation efficiencies of 81.7 ± 12.2 % and 50.9 ± 3.9 % for the large and small microspheres. Sustained drug release was observed in vitro over a clinically relevant 7-day period, with small and large microspheres exhibiting similar elution profiles. Antibiotic release generally followed microsphere degradation as measured by Ca and P ion release. Conclusions: This study demonstrated successful drug loading of calcium polyphosphate microspheres with minocycline. Furthermore, in vitro sustained release of minocycline over a 7-day period was observed, suggesting potential utility of this approach for treating periodontitis.

Spectroscopic and thermal degradation studies of novel hybrid polymer based on sodium polyphosphate - polystyrene

We have synthesized by the hydrophobic effect a new hybrid polymer material (HP) composed of segments of different solubility: polystyrene (hydrophobic) and sodium metaphosphate (hydrophilic). The structure and thermal stability of these hybrid materials were investigated and compared to the starting materials using X-ray diffraction (XRD), 31P Nuclear Magnetic Resonance, Raman spectroscopy and thermogravimetric analysis (TGA).The structure of the hybrid material consists of a mixture of phosphate compounds resulting from the hydrolysis of NaPO3. The phosphate groups have probably formed hydrogen bonds with aromatic CH. Furthermore, the delocalization of the electrons in the aromatic group generates negative poles that can interact with the positively charged Na ion, forming a cation-Ï€ interaction.The thermal characterization of these hybrids shows a clear improvement of the thermal property. TGA results show that phosphates increase HP residues yields at 600°C. Thus, Raman spectroscopy results provide evidence for the formation of residues having an aromatic phosphocarbon and an aromatic graphitic structure.

EFFECT OF SUCROSE AND SODIUM POLYPHOSPHATE ON RETROGRADATION OF RICE STARCHES

Starch retrogradation is a process occurred in many food products made from starch-containing raw materials. It affects qualities of food during storage. In this research, the effects of sucrose and phosphate on rice starch retrogradation were studied. Experiments were conducted with sucrose content ranged from 1 – 5 % (w/w) and sodium polyphosphate – from 0.1 – 1 % (w/w). Results showed that sucrose and polyphosphate reduced the syneresis of starch gel 1.19 - 1.44 and 4.6 - 4.87 times respectively. Both substances reduced the hardness of starch gel, but sucrose reduced the stickiness while polyphosphate increased stickiness of rice starch gel.