A simple route for preparation of pH-sensitive hydrogels by using egg white proteins in alginate scaffold for the encapsulation of probiotics

Abstract

Aims: In the present study, we evaluated the use of egg white proteins in alginate scaffolds and calcium alginate for the formulation of Lactobacillus casei and Lactobacillus acidophilus in the stomach acidic conditions. Material and Methods: after microorganism’s encapsulation in egg white proteins in alginate, survival assays and release in different conditions were evaluated. Scanning electron microscope and Fourier-transform infrared spectroscopy were used for analysis. Results: The results showed the high potential of this type of formulation in protecting the probiotics from stomach acidic conditions that is due to the significant increase in survival of the bacteria. Our study showed that the viability of the L. casei to free L. acidophilus had much less, however, with the encapsulation of the bacteria Egg white proteins in Alginate increased their survival significantly. Specially for the L. casei. Swelling and shrinkage behavior of egg white proteins in alginate capsules in different pH showed that the swelling of the capsule in the distilled water in the neutral terms had more inflation- capacity than similar position in terms of gastric acidity. Conclusions: the use of egg white proteins-Alginate for encapsulation of probiotics enhanced the stability of these microorganisms in simulated gastric environments adverse conditions.

Immobilization and microencapsulation of Lactobacillus caseii and Lactobacillus plantarum using zeolite base and evaluating their viability in gastroesophageal-intestine simulated condition

“…The prepared suspension was placed in an ultrasonic bath for 30 min to have a uniform mixture. 28 The activated bacteria were added to the MRSzeolite mixture and were incubated at 37°C by shaking.…”

“…After cooling of sodium alginate solution, active L. casei and L. plantarum obtained from the centrifuge and were added to the solution. 28 To produce the capsule seeds, alginate containing bacteria was extruded by the extrusion method to the firming sterile solution of 0.2M calcium chloride at 25°C and was then stirred with the magnetic stirrer at 150 rpm. After 1h, the seeds were removed from the firming medium and rinse twice with buffer solution to wash the encapsulated bacteria.…”

Application of Vortex Generators to Remove Heat Trapped in Closed Channels

“…Various techniques can be introduced as a passive method to increase heat transfer. These include changes in the roughness of the pages [20], changes in geometry [21], the use of generator vortex [22,23] and vertex generators [24,25] are protruding protrusions in the system that cause heat transfer in the trapped system by changing the direction of the fluid and creating secondary currents, thus increasing the heat transfer and preventing the local temperature from rising. Qu et al [22] increased the heat and mass transfer in a microchannel through the oscillations of a flexible generator vortex.…”