Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)protein-derived antioxidant peptides:mechanisms of action and structure-activity relationship in Caco-2 cell models

Excessive reactive oxygen species(ROS)can cause oxidative damage and lead to various metabolic disease.Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)is a new kind of protein-rich functional food,the protein in which has been proved to have good antioxidant capacity.In this study,in order to further explore the antioxidant mechanism of Tartary buckwheat protein,4 peptides(CR-8,LR-8,GK-10 and SR-12)were isolated and identified from it.H2 O2 was used to induce oxidative damage to Caco-2 cells to evaluate antioxidant capacity of these peptides.The results of superoxide dismutase(SOD),total antioxidant capacity(T-AOC)and mitochondrial membrane potential etc.showed that these peptides have superior antioxidant capacity.CR-8 has the best antioxidant capacity.In order to further clarify the antioxidant mechanism of CR-8,metabolomics was used to analyze related metabolites and metabolic pathways.The results showed that after CR-8 intervention,the content of metabolites such as L-acetyl carnitine has increased.This indicated that CR-8 can improve the antioxidant capacity of damaged cells by intervening in multiple metabolic pathways.This also revealed the anti-oxidant mechanism of tartary buckwheat protein.In conclusion,it provided a theoretical basis for further studying the activity of tartary buckwheat portein and utilizing buckwheat resources.

Effects of exogenous strain fermentation on protein structure and allergenicity of Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn.)

Tartary buckwheat contains high nutrition,its protein supports numerous biological functions and can be used by celiac disease patients.But its protein is a potential allergen.It’s necessary to explore methods that can effectively degrade Tartary buckwheat allergens.In this study,the exogenous strains Weissella cibaria,Lactococcus taiwanensis,Pediococcus pentosaceus,Lactobacillus curvatus,and Wickerhamomyces anomalus were added to dough respectively,which was fermented to explore the physicochemical properties of sourdough fermented by different strains and the changes in the allergen reactive and protein structure.ELISA results showed that fermentation decreased the allergen activity in Tartary buckwheat by 39.1%-82.8%.Protein structural analysis showed that the protein surface hydrophobicity decreased by 94.3%-98.2%,and relativeβ-turn decreased by 96.1%.The results showed that fermentation of Lactococcus taiwanensis and Pediococcus pentosaceus could effectively reduce the allergenicity of Tartary buckwheat,and the effect of fermentation of these two strains on the allergenicity of Tartary buckwheat was closely related to the changes in protein conformation.