Fig. 3

Stress resistance test of S. boulardii bioactive material. A Fluorescence images of PI-positive cells of free S. boulardii and S. boulardii bioactive material. Free S. boulardii and S. boulardii bioactive material were cultured with Cu²⁺ (2 mg/mL) and H₂O₂ solution (5 mmol/L) for 2 h and then stained by PI. Bar = 50 μm. Histogram analysis of B MTT and C ATP content of free S. boulardii and S. boulardii bioactive material after culturing with Cu²⁺ and H₂O₂ solution. D ATP content (right) and MTT activity (left) of S. boulardii bioactive material before (normal) and after (antagonism) culturing with C. albicans for 1 h. E Schematic diagram of construction process of S. boulardii (pGK1-MCP1) bioactive material. F Gene expression levels of MCP1 of S. boulardii (pGK1-MCP1) analyzed by RT-PCR using ACT1 as the normalization gene. G Western blotting analysis of Mcp1-GFP. After the pGK1-Mcp1-GFP and Mcp1-GFP-URA3 strains were cultured in YPD for 4–6 h, anti-GFP was used for western blot analysis to detect Mcp1-GFP. Anti-tubulin antibody was used as the loading control to detect tubulin. H PI positivity rate, I MTT activity, and J ATP content of free S. boulardii, free S. boulardii (pGK1-MCP1), S. boulardii encapsulated in bioactive material, and S. boulardii (pGK1-MCP1) encapsulated in bioactive material after the samples were cultured with Cu²⁺ (2 mg/mL) and H₂O₂ solution (5 mmol/L) for 2 h. Statistical significance was defined based on the different p-values: *p < 0.05, **p < 0.01, and ***p < 0.001