Self‐Healing of Cracks in Concrete Using Bacillus Strains Encapsulated in Sodium Alginate Beads

2020 ◽  
Vol 5 (1) ◽  
pp. 312-323 ◽  
Author(s):  
Saman Shahid ◽  
Muhammad A. Aslam ◽  
Shahid Ali ◽  
Mariam Zameer ◽  
Muhammad Faisal
Author(s):  
Bipul Nath ◽  
Santimoni Saikia

In the present investigation, sodium alginate based multiparticulate system overcoated with time and pH dependent polymer was studied in the form of oral pulsatile system to achieve pulsatile with sustained release of aceclofenac for chronotherapy of rheumatoid arthritis seven batches of micro beads with varying concentration of sodium alginate (2-5 %) were prepared by ionotropic-gelation method using CaCl2 as cross-linking agent. The prepared Ca-alginate beads were coated with 5% Eudragit L100 and filled into pulsatile capsule with varying proportion of plugging materials. Drug loaded microbeads were investigated for physicochemical properties and drug release characteristics. The mean particle sizes of drug-loaded microbeads were found to be in the range 596±1.1 to 860 ± 1.2 micron and %DEE in the range of 65-85%. FT-IR and DSC studies revealed the absence of drug polymer interactions. The release of aceclofenac from formulations F1 to F7 in buffer media (pH 6.8) at the end of 5h was 65.6, 60.7, 55.7, 41.2, 39.2, 27 and 25% respectively. Pulsatile system filled with eudragit coated Ca-alginate microbeads (F2) showed better drug content, particle size, surface topography, in-vitro drug release in a controlled manner. Different plugging materials like Sterculia gum, HPMC K4M and Carbopol were used in the design of pulsatile capsule. The pulsatile system remained intact in buffer pH 1.2 for 2 hours due to enteric coat of the system with HPMCP. The enteric coat dissolved when the pH of medium was changed to 7.4. The pulsatile system developed with Sterculia gum as plugging material showed satisfactory lag period when compared to HPMC and Carbopol.


Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 724
Author(s):  
Miguel L. Sousa-Dias ◽  
Vanessa Branco Paula ◽  
Luís G. Dias ◽  
Letícia M. Estevinho

This work studied the production of mead using second category honey and the immobilized cells of Saccharomyces cerevisiae in sodium alginate, with concentrations of 2% and 4%, and their reuse in five successive fermentations. The immobilized cells with 4% alginate beads were mechanically more stable and able to allow a greater number of reuses, making the process more economical. The fermentation’s consumption of sugars with free cells (control) and immobilized cells showed a similar profile, being completed close to 72 h, while the first use of immobilized cells finished at 96 h. The immobilized cells did not significantly influence some oenological parameters, such as the yield of the consumed sugars/ethanol, the alcohol content, the pH and the total acidity. There was a slight increase in the volatile acidity and a decrease in the production of SO2. The alginate concentrations did not significantly influence either the parameters used to monitor the fermentation process or the characteristics of the mead. Mead fermentations with immobilized cells showed the release of cells into the wort due to the disintegration of the beads, indicating that the matrix used for the yeast’s immobilization should be optimized, considering the mead production medium.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Stefano Focaroli ◽  
Gabriella Teti ◽  
Viviana Salvatore ◽  
Isabella Orienti ◽  
Mirella Falconi

Articular cartilage is a highly organized tissue with complex biomechanical properties. However, injuries to the cartilage usually lead to numerous health concerns and often culminate in disabling symptoms, due to the poor intrinsic capacity of this tissue for self-healing. Although various approaches are proposed for the regeneration of cartilage, its repair still represents an enormous challenge for orthopedic surgeons. The field of tissue engineering currently offers some of the most promising strategies for cartilage restoration, in which assorted biomaterials and cell-based therapies are combined to develop new therapeutic regimens for tissue replacement. The current study describes thein vitrobehavior of human adipose-derived mesenchymal stem cells (hADSCs) encapsulated within calcium/cobalt (Ca/Co) alginate beads. These novel chondrogenesis-promoting scaffolds take advantage of the synergy between the alginate matrix and Co+2ions, without employing costly growth factors (e.g., transforming growth factor betas (TGF-βs) or bone morphogenetic proteins (BMPs)) to direct hADSC differentiation into cartilage-producing chondrocytes.


2015 ◽  
pp. 207-218
Author(s):  
Jovana Djuran ◽  
Zorana Roncevic ◽  
Bojana Bajic ◽  
Sinisa Dodic ◽  
Jovana Grahovac ◽  
...  

Ethanol is an important industrial chemical with emerging potential as a biofuel to replace fossil fuels. In order to enhance the efficiency and yield of alcoholic fermentation, combined techniques such as cells immobilization and media optimization have been used. The aim of this study was the optimization of sodium alginate concentration and glucose and yeast extract content in the media for ethanol production with immobilized cells of Saccharomyces cerevisiae. Optimization of these parameters was attempted by using a Box-Behnken design using the response surface methodology. The obtained model predicts that the maximum ethanol content of 7.21% (v/v) is produced when the optimal values of sodium alginate concentration and initial content of glucose and yeast extract in the medium are 22.84 g/L, 196.42 g/L and 3.77 g/L, respectively. To minimize the number of yeast cells "eluted" from the alginate beads and residual glucose content in fermented media, additional two sets of optimization were made. The obtained results can be used for further techno-economic analyses of the process to select the optimum conditions of the fermentation process for industrial application.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10165
Author(s):  
Nucharee Juntarachot ◽  
Sasithorn Sirilun ◽  
Duangporn Kantachote ◽  
Phakkharawat Sittiprapaporn ◽  
Piyachat Tongpong ◽  
...  

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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