A green nanocoating approach to Lactobacillus plantarum using tea residue-derived phenolic compounds and cellulose nanocrystals

Nanocoating technologies effectively enhance the stability and functionality of probiotics, overcoming challenges in their delivery and survival through the gastrointestinal tract. This study introduces a nanocoating method incorporating phenolic compounds and cellulose nanocrystals (CNCs) from green tea residues, aimed at improving the performance of Lactobacillus plantarum (LP). A cell-mediated catalytic single-cell coating process was developed, to optimize the formation of a polymeric phenolic layer and facilitating CNC adhesion, while preserving bacterial viability and growth. The coated LP showed improved tolerance to simulated gastric fluid and bile salts, and maintained significantly higher viability under oxidative stress. In a Caco-2 cell model exposed to H₂O₂, the phenolic-coated LP significantly improved cell viability compared to pristine LP, confirming its antioxidant efficacy. Furthermore, CNC incorporation increased the mucoadhesive properties of coated LP, as evidenced by in vitro and ex vivo assays. This study highlights the potential of repurposing green tea byproducts to develop sustainable and multifunctional nanocoatings. By improving probiotic survival, antioxidant activity, and mucosal adhesion, this sustainable approach presents a promising advancement in probiotic delivery systems.