Impact of alginate concentration on the stability of agglomerates made of TiO2 engineered nanoparticles: Water hardness and pH effects

Background The accumulation of plaque causes oral diseases. Dental plaque is formed on teeth surfaces by oral bacterial pathogens, particularly Streptococcus mutans, in the oral cavity. Dextranase is one of the enzymes involved in antiplaque accumulation as it can prevent dental caries by the degradation of dextran, which is a component of plaque biofilm. This led to the idea of creating toothpaste containing dextranase for preventing oral diseases. However, the dextranase enzyme must be stable in the product; therefore, encapsulation is an attractive way to increase the stability of this enzyme. Methods The activity of food-grade fungal dextranase was measured on the basis of increasing ratio of reducing sugar concentration, determined by the reaction with 3, 5-dinitrosalicylic acid reagent. The efficiency of the dextranase enzyme was investigated based on its minimal inhibitory concentration (MIC) against biofilm formation by S. mutans ATCC 25175. Box-Behnken design (BBD) was used to study the three factors affecting encapsulation: pH, calcium chloride concentration, and sodium alginate concentration. Encapsulation efficiency (% EE) and the activity of dextranase enzyme trapped in alginate beads were determined. Then, the encapsulated dextranase in alginate beads was added to toothpaste base, and the stability of the enzyme was examined. Finally, sensory test and safety evaluation of toothpaste containing encapsulated dextranase were done. Results The highest activity of the dextranase enzyme was 4401.71 unit/g at a pH of 6 and 37 °C. The dextranase at its MIC (4.5 unit/g) showed strong inhibition against the growth of S. mutans. This enzyme at 1/2 MIC also showed a remarkable decrease in biofilm formation by S. mutans. The most effective condition of dextranase encapsulation was at a pH of 7, 20% w/v calcium chloride and 0.85% w/v sodium alginate. Toothpaste containing encapsulated dextranase alginate beads produced under suitable condition was stable after 3 months of storage, while the sensory test of the product was accepted at level 3 (like slightly), and it was safe. Conclusion This research achieved an alternative health product for oral care by formulating toothpaste with dextranase encapsulated in effective alginate beads to act against cariogenic bacteria, like S. mutants, by preventing dental plaque.

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Investigation of the Influence of Calcium Salts and Gelling Time on the Structural Mechanical Properties of Fruit Jam

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Food Science and Technology ◽

10.15835/buasvmcn-fst:2020.0010 ◽

2020 ◽

Vol 77 (2) ◽

pp. 88

Author(s):

Zdravko MANEV ◽

Nadezhda PETKOVA

Keyword(s):

Calcium Ion ◽

Alginate Beads ◽

Rupture Force ◽

Practical Application ◽

Bioactive Substances ◽

Calcium Salts ◽

Alginate Concentration ◽

Different Types ◽

The Stability ◽

Gelling Time

Alginate beads attract attention as a encapsulation matrix of bioactive substances in food. However, the stability of beads depends on calcium ion and sodium alginate concentration, gelling time and others factors. The aim of this study is to investigate the influence of different types of calcium salts on the structural and mechanical parameters - the rupture force and rupture deformation at different gelling times of the pear jam prepared with soluble dietary fibers and inulin. The relationships between the rupture force and rupture deformation of the fruit jams were established. By increasing the gelling time from 24 hours to 48 hours, the rupture deformation of jams with 7% calcium lactate were reduced and in those with 7% CaCl2 the rupture forces increases. Any change in rupture force was observed for the jam with 3.5% CaCl2. This study demonstrated the practical application of different calcium salts for preparation of stable pear jam.

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Behavior of TiO2 and CeO2 Nanoparticles and Polystyrene Nanoplastics in Bottled Mineral, Drinking and Lake Geneva Waters. Impact of Water Hardness and Natural Organic Matter on Nanoparticle Surface Properties and Aggregation

Water ◽

10.3390/w11040721 ◽

2019 ◽

Vol 11 (4) ◽

pp. 721 ◽

Cited By ~ 13

Author(s):

Lina Ramirez ◽

Stephan Ramseier Gentile ◽

Stéphane Zimmermann ◽

Serge Stoll

Keyword(s):

Drinking Water ◽

Organic Matter ◽

Natural Organic Matter ◽

Drinking Water Treatment ◽

Water Hardness ◽

Engineered Nanoparticles ◽

Mineral Waters ◽

Lake Geneva ◽

Water Treatment Process ◽

The Impact

Intensive use of engineered nanoparticles (NPs) in daily products ineluctably results in their release into aquatic systems and consequently into drinking water resources. Therefore, understanding NPs behavior in various waters from naturel to mineral waters is crucial for risk assessment evaluation and the efficient removal of NPs during the drinking water treatment process. In this study, the impact of relevant physicochemical parameters, such as pH, water hardness, and presence of natural organic matter (NOM) on the surface charge properties and aggregation abilities of both NPs and nanoplastic particles is investigated. TiO2, CeO2, and Polystyrene (PS) nanoplastics are selected, owing to their large number applications and contrasting characteristics at environmental pH. Experiments are performed in different water samples, including, ultrapure water, three bottled mineral waters, Lake Geneva, and drinking water produced from Lake Geneva. Our findings demonstrate that both water hardness and negatively charged natural organic matter concentrations, which were measured via dissolved organic carbon determination, are playing important roles. At environmental pH, when negatively charged nanoparticles are considered, specific cation adsorption is promoting aggregation so long as NOM concentration is limited. On the other hand, NOM adsorption is expected to be a key process in NPs destabilization when positively charged PS nanoplastics are considered.

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Impact of ZnO Concentration on the Stability of Agglomerates of TiO2 Engineered Nanoparticles: Effects of the pH, Ionic Strength and Zeta Potential

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1012.167 ◽

2020 ◽

Vol 1012 ◽

pp. 167-172

Author(s):

Elizabeth Mendes de Oliveira ◽

Izabella Christynne Ribeiro Pinto Valadão ◽

Jose Adilson de Castro ◽

Leonardo Martins da Silval ◽

Darlene Souza da Silva ◽

...

Keyword(s):

Ionic Strength ◽

Zeta Potential ◽

Large Scale ◽

Soil Column ◽

Equilibrium Concentration ◽

Engineered Nanoparticles ◽

Leaching Experiments ◽

The Stability ◽

Potential Interactions ◽

Influence Of Ph

The stability of nanoparticles in natural aquatic systems is of great interest to the environmental risk assessment. The relevance of this study lies in the fact that nanoparticles are being produced and used in commercial products on a large scale, which makes the need to study its transport through the environment, especially in soil and water important due to their potential interactions with the ecosystems. In this research, the effects of nanoparticles of zinc oxide (NPZnO) in the behavior of nanoparticles of titanium dioxide (NPTiO2) was investigated. The influence of pH, ionic strength and zeta potential of the hazardous nanoparticles into soil landfills are studied using experimental procedures. Leaching experiments were prepared within soil column simulating landfills layers. Leaching experiments were carried out to simulate the capture and attenuation of these nanomaterials in municipal waste landfills. The results found that the presence of NPTiO2 in suspensions increases the stability of the suspensions keeping higher nanoparticles concentrations, while NPZnO promotes rapid sedimentation with lower equilibrium concentration of nanoparticles.

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Temperature and pH effects on the stability and rheological behavior of the aqueous suspensions of smart polymers based onN-isopropylacrylamide, chitosan, and acrylic acid

Journal of Applied Polymer Science ◽

10.1002/app.38750 ◽

2012 ◽

Vol 129 (1) ◽

pp. 334-345 ◽

Cited By ~ 21

Author(s):

Nívia do Nascimento Marques ◽

Priscila Schroeder Curti ◽

Ana Maria da Silva Maia ◽

Rosangela de Carvalho Balaban

Keyword(s):

Acrylic Acid ◽

Rheological Behavior ◽

Ph Effects ◽

Smart Polymers ◽

Aqueous Suspensions ◽

The Stability

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The stability of amoxicillin trihydrate and potassium clavulanate combination in aqueous solutions

Acta Veterinaria Hungarica ◽

10.1556/avet.57.2009.4.3 ◽

2009 ◽

Vol 57 (4) ◽

pp. 485-493 ◽

Cited By ~ 13

Author(s):

Ákos Jerzsele ◽

Gábor Nagy

Keyword(s):

Environmental Factors ◽

Aqueous Solutions ◽

Clavulanic Acid ◽

Decomposition Rate ◽

Water Hardness ◽

Ph Values ◽

Amoxicillin Trihydrate ◽

Amoxicillin Clavulanic Acid ◽

Potassium Clavulanate ◽

The Stability

The effect of various environmental factors on the stability of aqueous solutions of amoxicillin-clavulanic acid combination in a veterinary water-soluble powder product was investigated. In the swine industry, the combination is administered via the drinking water, where both substances are quickly decomposed depending on several environmental factors. The degradation rate of the substances was determined in solutions of different water hardness levels (German hardness of 2, 6 and 10) and pH values (3.0, 7.0 and 10.0), and in troughs made of different materials (metal or plastic). Increasing the water hardness decreased the stability of both substances, amoxicillin being more stable at each hardness value than clavulanate. Amoxicillin trihydrate proved to be most stable at an acidic pH, while increasing the pH decreased its stability (P < 0.05). Maximum stability of potassium clavulanate was experienced at neutral pH, while its decomposition rate was significantly higher at acidic and alkaline pH values (P < 0.01). The stability of the amoxicillin-clavulanic acid combination depends mainly on the less stable clavulanate, although the effect of metallic ions significantly increased the decomposition rate of amoxicillin, rendering it less stable in metal troughs than clavulanate (P < 0.05). Therefore, the amoxicillin-clavulanic acid combination should be administered to the animals in soft water, at neutral pH and in plastic troughs.

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The Stability of Tropomyosin at Acid pH: Effects of Anion Binding

Journal of Structural Biology ◽

10.1006/jsbi.1998.3973 ◽

1998 ◽

Vol 122 (1-2) ◽

pp. 176-179 ◽

Cited By ~ 10

Author(s):

Sherwin S Lehrer ◽

Amy Yuan

Keyword(s):

Anion Binding ◽

Ph Effects ◽

Acid Ph ◽

The Stability

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Influence of Chitosan-Alginate Microcapsules Containing Anti-Vibrio Harveyi IgY in the Gastrointestinal Tract Simulation

Modern Applied Science ◽

10.5539/mas.v9n12p110 ◽

2015 ◽

Vol 9 (12) ◽

pp. 110 ◽

Cited By ~ 1

Author(s):

Kawin Punyokun ◽

Ratchanee Hongprayoon ◽

Prapansak Srisapoome ◽

Theerapol Sirinarumitre

Keyword(s):

Egg Yolk ◽

Gastric Fluid ◽

Simulated Gastric Fluid ◽

Gastrointestinal Infections ◽

Simulated Intestinal Fluid ◽

Egg Yolk Immunoglobulin ◽

Alginate Concentration ◽

Cacl2 Concentration ◽

The Stability ◽

Processing Factors

Egg yolk immunoglobulin (IgY) is an alternative treatment for the prevention of gastrointestinal infections in pigs, cows, chickens and fish. In our previous report, we preliminarily proved that anti-V. harveyi IgY had effective potential to control luminous disease in black tiger shrimp. However,IgY activity may be reduced or destroyed by gastric conditions, particularly low pH and digestive enzymes. Therefore, it is necessary to find an effective method to preserve the therapeutic function of IgY antibodies during gastric passage. Chitosan-alginate microcapsules have been developed to protect IgY from gastric inactivation. The processing factors included different forms of chitosan and alginate, while a CaCl2 concentration and encapsulation medium was investigated. The optimum results were obtained under the following conditions: High Mw chitosan concentration 0.2% (w/v), medium viscosity alginate concentration 2% (w/v), CaCl2 concentration 0.5% (w/v). The stability of IgY in simulated gastric fluid (SGF, pH 1.2) was greatly improved by encapsulation in chitosan-alginate microcapsules, and retained greater than 90% activity after 2 h exposure to SGF. Less than 10% IgY was released upon the microcapsules’ exposure to SGF for 2 h, and more than 80% IgY was released upon the microcapsules’ exposure to simulated intestinal fluid (SIF, pH 6.8) for 16 h.

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The Layered Encapsulation of Vitamin B2 and β-Carotene in Multilayer Alginate/Chitosan Gel Microspheres: Improving the Bioaccessibility of Vitamin B2 and β-Carotene

Foods ◽

10.3390/foods11010020 ◽

2021 ◽

Vol 11 (1) ◽

pp. 20

Author(s):

Peilong Liao ◽

Shicheng Dai ◽

Ziteng Lian ◽

Xiaohong Tong ◽

Sai Yang ◽

...

Keyword(s):

Multilayered Structure ◽

Vitamin B2 ◽

X Ray Diffraction ◽

Bioactive Substances ◽

Excellent Thermal Stability ◽

Ph Response ◽

Alginate Concentration ◽

The Stability ◽

Β Carotene ◽

Simultaneous Delivery

This research underlines the potential of alginate multilayered gel microspheres for the layered encapsulation and the simultaneous delivery of vitamin B2 (VB) and β-carotene (BC). Chitosan was used to improve the stability and controlled release ability of alginate-based gel microspheres. It was shown that a clear multilayered structure possessed the characteristics of pH response, and excellent thermal stability. The sodium alginate concentration and the number of layers had notable effects on mechanical properties and particle size of gel microspheres. Fourier-transform infrared spectroscopy and X-ray diffraction analyses further proved that VB and BC were encapsulated within the gel microspheres. Compared with the three-layer VB-loaded gel microspheres, the total release of VB from the three-layer VB and BC-loaded gel decreased from 93.23 to 85.58%. The total release of BC from the three-layer VB and BC-loaded gel increased from 66.11 to 69.24% compared with three-layer BC-loaded gel. The simultaneous encapsulation of VB and BC in multilayered gel microspheres can markedly improve their bioaccessibility and bioavailability. These results showed the multilayer gel microspheres synthesized herein have potential for applications in the layered encapsulation and simultaneous delivery of various bioactive substances to the intestinal tract.

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pH effects on the stability and dimerization of procaspase-3

Protein Science ◽

10.1110/ps.041003305 ◽

2009 ◽

Vol 14 (1) ◽

pp. 24-36 ◽

Cited By ~ 15

Author(s):

Kakoli Bose ◽

A. Clay Clark

Keyword(s):

Ph Effects ◽

The Stability

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