Mechanism of co-encapsulating highland barley β-glucan to improve the gastrointestinal bioavailability of probiotics

Probiotics have shown considerable health benefits, especially concerning gastrointestinal health, however, environmental stress during production and transit through the gastrointestinal digestive system will adversely impact their viability. This study aimed to explore the protective effects of co-encapsulating highland barley β-glucan (HBBG) with probiotics on cell bioavailability during gastrointestinal digestion. The incorporation of HBBG (0.5% w/w) significantly improved probiotic viability and enhanced microcapsule morphology during spray drying. Both in vivo and in vitro gastrointestinal digestion assays demonstrated superior probiotic survival rates (>8.5 Log CFU/g) within HBBG-containing microcapsule samples. Furthermore, the production of short-chain fatty acids, particularly acetic acid reached 9.22 mM) and the growth of beneficial gut microbiota (e.g., Lactobacillus and Bifidobacterium) were both enhanced significantly. The findings highlighted the prominent prebiotic potential of HBBG and its synergistic role in improving probiotic stability and functionality during gastrointestinal digestion.