Table 2.

Summary of three‐layer microparticles for probiotic delivery

Fabrication technique	First layer component/s	Second layer component/s	Third layercomponent/s	Probiotic strain	Results	Ref.
W1/O/W2	MRS broth	Medium chain triglycerides oil + polyglycerol polyricinoleate	Poloxamer 407	Lactobacillus reuteri	Encapsulated formulation enhanced the viability of probiotic during cold storage, as compared to control. Upon simulated gastrointestinal conditions the viability decreased with a higher rate for control compared to encapsulated samples.	[ 54 ]
W1/O/W2	Ca cross‐linked alginate	Soybean oil + polyglycerol polyricinoleate	Bacterial cellulose	Lactobacillus acidophilus	High survival rate (84%) of encapsulated cells after exposure to simulated gastrointestinal conditions, compared to the free cells (undetectable level). Cells released from particles showed three times higher colon‐adhesion efficiency than that of free cells (Ex vivo everted gut sac model).	[ 111 ]
W1/O/W2	Fructooligosaccharides	Medium chain triglycerides oil + polyglycerol polyricinoleate	Ca‐EDTA cross‐linked alginate + whey protein isolate‐epigallocatechin‐3‐gallate	Lactobacillus plantarum	The probiotic viability in the W1/O/W2 double emulsion prepared with the optimal parameters experienced no loss after full simulated gastrointestinal digestion.	[ 57 ]
W1/O/W2	MRS broth	Corn oil + polyglycerol polyricinoleate	Gelatine + gum arabic	Lactobacillus plantarum	After exposure to simulated gastrointestinal conditions, viability of the encapsulated cells was 80.4% whereas it was only 25.0% for the free cells at 37 °C.	[ 55 ]
Layer‐by‐layer	Chitosan	Carboxymethyl cellulose	Chitosan	Lactobacillus acidophilus	Lower loss in cell viability for coated cells (8%) when compared to free cells (27%), exposed to sequential freezing and freeze‐drying. Significantly less reduction in cell viability (12%) after exposure to gastrointestinal conditions, compared to that of free cells (61%).	[ 113 ]
Extrusion + Layer‐by‐layer	Xanthan	Chitosan	Xanthan	Lactobacillus acidophilus	Higher cell viability after gastrointestinal conditions when compared to xanthan‐chitosan particles.	[ 64 ]
Extrusion + Layer‐by‐layer	Ca cross‐linked alginate	Chitosan	Methacrylic acid‐Methyl methacrylate Copolymer (1:2)	Lactobacillus acidophilus or Lactobacillus plantarum	Improved cell viability after exposure to both gastrointestinal conditions, and incorporation into yogurt.	[ 79 ]
Co‐extrusion + Dip coating	Alginate + fish oil	Ca cross‐linked alginate + pectin	Soy protein isolate	lactobacillus plantarum	Oil‐containing microparticles significantly improved the encapsulation efficiency of probiotics and resulted in highest viability of probiotics when exposed to simulated gastrointestinal conditions (92%).	[ 62 ]
Co‐extrusion + Dip coating	Alginate	Ca‐cross‐linked alginate	Protamine	Lactobacillus casei	The diffusional permeability coefficient (P value) was significantly lower for protamine‐coated particles compared to two‐layer particles. Protamine‐coated particles showed responsive release of cells after exposure to intestinal pH.	[ 40 ]