Colon targeting and microencapsulation ofprobiotics: A comprehensive review

Abstract

Maintaining physiological balance and disease prevention depends much on the human microbiota, especially the
gut microbiota. Disruptions in microbial populations are linked to various health disorders, including inflammatory,
metabolic, and autoimmune diseases. Probiotics, which are live microorganisms that provide health benefits
when administered in adequate amounts, have emerged as promising biotherapeutics. However, their viability
through the harsh gastrointestinal tract remains a significant concern. This review highlights the importance
of colon-targeted delivery systems and explores various strategies, such as pH-, time-, microbe-triggered, and
combination-targeting approaches, for effective probiotic release at the colonic site. Furthermore, it provides
an in-depth discussion of microencapsulation technologies, including coacervation, extrusion, emulsification,
spray drying, and advanced techniques such as spray-freeze drying, electrospinning, and fluid bed coating.
Emphasis is placed on the mechanisms, materials, advantages, and limitations of each method. A comprehensive
understanding of colon physiology and encapsulation science is essential for developing effective formulations
that ensure probiotic viability and therapeutic efficacy. Future research should focus on optimizing these systems
to enhance site-specific delivery, shelf stability, and large-scale applicability.