Effects of selenium biofortification on Pleurotus eryngii protein structure and digestive properties and its mitigation of lead toxicity: An in vitro and in vivo study.

The development of safe and efficient dietary selenium sources to promote lead excretion is of great importance for public health. In this research, proteins from original Pleurotus eryngii (PEP) and Se-enriched P. eryngii (SePEP, Se content: 360.64 ± 3.11 mg/kg) were extracted and purified respectively for the further comparison of structural and digestive characteristics. Caco-2 monolayer membrane, in vitro simulated fermentation and acute lead exposure mice model were constructed to evaluate the effects of PEP and SePEP on lead excretion. The results indicated that Se biofortification significantly altered the amino acid composition and reduced the total sulfhydryl content of proteins (p < 0.05). SePEP could better alleviate lead-induced intestinal barrier damage and inhibit the absorption and accumulation of lead in both cell and mice models. Furthermore, SePEP promoted fecal adsorption and excretion of lead via regulating gut microbiota composition. SePEP can be considered a potentially functional Se source to promote lead excretion.