Emerging Synbiotic Interactions between Vanillin and the Probiotic Bacterium Lacticaseibacillus rhamnosus GG Determined via Physiological and Proteomic Approaches

Abstract

Probiotics are beneficial microorganisms that reside in the intestines and support host health when consumed in adequate amounts. One well-studied strain, Lacticaseibacillus rhamnosus GG (LGG), contributes to gut microbiota balance and immune function. Vanillin, a phenolic compound known for its antioxidant, antibacterial, and anticancer properties, also plays an important role as a flavoring agent in the food industry. In the gastrointestinal tract, vanillin and probiotics interact to enhance probiotic properties. This study investigates the effect of vanillin on the exoproteome and physiological traits of LGG, such as autoaggregation, coaggregation, and antioxidant activity. The results showed that vanillin improved LGG's aggregation properties. Exoproteomic changes were assessed using mass spectrometry, 2D gel electrophoresis, and image analysis. SameSpots software revealed protein spots with differential intensities between control and vanillin-treated samples. Notably, cytidylate kinase abundance decreased 1.6-fold in the presence of vanillin. These results indicate that LGG and vanillin together may function effectively as a synbiotic combination.