Metabolomics analysis of osmotic tolerance enhancement mechanism of wheat gluten peptides on industrial yeast

Plant-derived wheat gluten peptides have an effective protective ability on industrial yeast against osmotic stress, the enhancement mechanism of osmotic tolerance in yeast by wheat gluten peptides addition was clarified in this study. Results showed that wheat gluten peptides addition increased the intracellular pH and trehalose levels of yeast under osmotic stress, compared to the control. Furthermore, peptides supplementation could regulate the antioxidant defense system and reduce the reactive oxygen species accumulation in yeast, including the increase of intracellular glutathione levels and the activities of antioxidant enzymes catalase and glutathione peroxidase. Metabolomic results indicated that the enhancement mechanism of wheat gluten peptides on yeast osmotic tolerance was related to the promotion of arginine and proline metabolism, pantothenate and coenzyme A biosynthesis, pyrimidine metabolism, and cysteine and methionine metabolism pathways. These results provide new insight into the enhancement mechanism of yeast stress tolerance by plant-derived peptides from a metabolic perspective.