Strain-Carrier Matching Strategy Enhances Gastrointestinal Survival and Mucosal Adhesion of Dietary Probiotics Encapsulated in Thiolated Pectin-Alginate Hydrogels.

This study addresses the limitations of conventional probiotic delivery systems by introducing a strain-carrier matching principle, which systematically aligns carrier properties with strain-specific characteristics. A thiolated low-methoxyl pectin/alginate composite hydrogel platform was developed, featuring a mucoadhesive outer layer with thiolated modified pectin to enhance intestinal retention. Two distinct carriers (pectin-based and alginate-based) were systematically evaluated across nine probiotic strains for encapsulation efficiency (92.44 ± 0.23% to 99.86 ± 0.13%), simulated gastrointestinal (GI) survival for 4 h (53.57 ± 0.12% to 96.04 ± 0.47%), and mucoadhesive capacity (22.23 ± 1.90% to 50.31 ± 1.81%). While both systems demonstrated strong adhesive and protective effects under simulated gastrointestinal conditions compared with free cells, significant strain-specific differences in encapsulation performance and survival were observed. Notably, intrinsically acid- and bile-tolerant strains (Lactiplantibacillus plantarum TM3-23 and Pediococcus acidilactici G1-14) exhibited a reduced relative enhancement, revealing that carrier efficacy is fundamentally determined by microbial surface physicochemical properties and inherent physiological resilience. These findings establish the critical "strain-encapsulation carrier" matching principle, revealing that optimal delivery requires aligning carrier properties with specific strain characteristics. This work transcends conventional encapsulation paradigms and provides a theoretical framework for designing next-generation functional foods and strain-carrier matching probiotic products that ensure enhanced intestinal mucoadhesion and stability.