Effect and mechanism of ovomucin on the physicochemical properties of <em>Lactobacillus plantarum</em> Lp90

Egg white ovomucin (OVM) has properties highly similar to intestinal mucin and is considered to have a protective effect on probiotics, but this remains to be confirmed. This study evaluated the effect of OVM on the probiotic viability and functionality of <em>Lactobacillus plantarum </em>Lp90 and explored the mechanism by which OVM affects Lp90 using proteomics. The results indicated that OVM treatment showed no adverse effects on Lp90 viability, but concentration-dependently enhanced its self-aggregation ability, with the H-OVM group (10 mg/mL) reaching up to 39.6%. Quantitative proteomic analysis revealed that L-OVM (3 mg/mL) and H-OVM treatments resulted in the differential expression of only 79 (4.42%) and 173 (9.68%) proteins, respectively, indicating OVM exerted a weak overall effect on Lp90. Analysis of the differentially expressed proteins revealed that L-OVM enhanced the environmental adaptability of Lp90 by regulating cell wall synthesis and modification and promoting the expression of various nutrient transport systems. This study clarified that OVM is beneficial to the self-aggregation and environmental adaptability of Lp90, demonstrating that OVM has potential as a probiotic protectant.