Abstract: To address the critical issue of low probiotic survival rates during food processing and oral delivery, this study encapsulated Lactobacillus acidophilus (LA) in a Ganoderma lucidum polysaccharide-based hydrogel (G-GLP) to develop a pH-responsive probiotic delivery system. G-GLP-LA exhibited a porous three-dimensional microstructure. The incorporation of LA did not alter the hydrogel’s structure or physical properties but enhanced its thermal stability. The encapsulated LA exhibited improved tolerance to heat treatment at 65 ℃ and to simulated gastrointestinal fluids. In vitro gastrointestinal release experiments showed that only 14.63% of LA was released in simulated gastric fluid, while the release rate in simulated intestinal fluid reached 83.87%, demonstrating pH-responsive release characteristics. Furthermore, the LA release behavior exhibited a high degree of agreement with both the zero-order kinetic model and the Korsmeyer-Peppas model. The release mechanism followed the Super Case II transport model, enabling a burst release of LA in simulated intestinal fluid. This hydrogel system provides an efficient and controllable protective strategy for the application of probiotics in food processing and oral delivery.

Key words: hydrogel; Ganoderma lucidum polysaccharides; probiotics; oral delivery