Introduction: Postbiotics refer to non-viable microbial cells, cell components, or metabolites that exert beneficial effects on host health. Compared with probiotics, these compounds exhibit higher stability, do not require cold-chain storage, and pose no risk of horizontal gene transfer or infection. Such features have positioned postbiotics as a safe and effective alternative in human health. In particular, key components include structural cell fragments, secondary metabolites, and genetic residues (DNA and RNA), while common producing strains are Lactobacillus, Bifidobacterium, Escherichia coli Nissle, and Saccharomyces boulardii.
Methods: Postbiotics influence host health through several pathways, including immune modulation by upregulating anti-inflammatory cytokines (e.g., IL-10) and reducing pro-inflammatory factors such as TNF-α, pathogen inhibition via competitive exclusion and antimicrobial metabolite production, enhancement of intestinal barrier integrity to prevent pathogen translocation, antioxidant activity to counteract oxidative stress, and metabolic regulation, particularly in lipid and glucose homeostasis.
The production of postbiotics generally involves three main steps: cultivation of microorganisms in suitable media, inactivation of cells through heat, irradiation, or ultrasonication, and extraction and purification of bioactive compounds by filtration, centrifugation, or chemical methods.
Moreover, to ensure quality and efficacy, several analytical and molecular methods are employed, including flow cytometry (particularly imaging-based models) for differentiating viable and inactivated cells, qPCR and dPCR for precise identification and quantification of target strains with optimized primers and validation, and chemical and biophysical approaches such as HPLC, NMR, and mass spectrometry for detecting and quantifying bioactive metabolites.
In addition, modern approaches like genetic engineering (CRISPR-Cas9) and metabolic engineering offer promising tools for pathway optimization, strain improvement, and enhanced production under industrial conditions.
Results: Postbiotics demonstrate therapeutic effects comparable to or even exceeding probiotics, without the risks of antibiotic resistance or infection. Specifically, their biomedical applications include modulating immune responses and suppressing inflammation (e.g., via NF-κB inhibition), improving gut health by strengthening epithelial barriers, antimicrobial effects through competitive interactions and metabolite secretion, metabolic regulation mediated by short-chain fatty acids (SCFAs), and cardioprotective effects through lipid-lowering mechanisms.
Furthermore, from an industrial perspective, postbiotics are increasingly applied across various sectors, including food and beverages (functional products with extended stability and no need for live microbes), nutritional supplements (capsules and powders stable at ambient temperatures), pharmaceuticals and biotechnology (anti-inflammatory and immunomodulatory agents), cosmeceuticals (antioxidant and anti-inflammatory compounds for skincare), and veterinary and agriculture (reducing antibiotic use by improving gut health in livestock).
Conclusion: Postbiotics represent a new generation of bioproducts combining high safety, physical stability, and therapeutic efficacy. They hold promise as adjunct therapies for inflammatory diseases and potentially cancer. Emerging technologies in biotechnology and nanotechnology will enhance production efficiency, and expanded preclinical and clinical research will accelerate their integration into mainstream medicine. Overall, postbiotics are poised to play a key role in future disease prevention and treatment.
Keywords: Postbiotics, Therapeutic agents, Immunomodulation, Gut health, Metabolic regulation