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 tract 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 the microcapsule morphology during spray drying. Both <i>in vivo</i> and <i>in vitro</i> gastrointestinal digestion assays demonstrated superior probiotic survival rates (>8.5 Log CFU per 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 (<i>e.g.</i>, <i>Lactobacillus</i> and <i>Bifidobacterium</i>) was enhanced significantly. The findings highlighted the prominent prebiotic potential of HBBG and its synergistic role in improving probiotic stability and functionality during gastrointestinal digestion.