Study on the reduction of Tartary buckwheat allergenicity during Pediococcus pentosaceus fermentation by HPLC-MS/MS analysis.

Tartary buckwheat contains more valuable nutrients than common buckwheat, but it also contains allergenic proteins that induce allergic reactions through an IgE-mediated response. Our study demonstrated that fermentation by Pediococcus pentosaceus degrades allergenic proteins in Tartary buckwheat, as confirmed by HPLC-MS/MS analysis of polypeptides. Our results showed significant degradation of the protein after 16 h of Pediococcus pentosaceus fermentation (PP16), leading to a reduction in IgE-binding activity. Comparison with unfermented Tartary buckwheat (UTB) peptides yielded 2042 fragments, of which 756 fragments associated with allergenic proteins were upregulated. Among them, the expression of 213 fragments was reduced by 71.83%. By performing bioactivity prediction on potential allergenic peptide fragments, we identified six peptide fragments derived from Fagt 1, potentially contributing to the residual allergenicity in PP16. These suggest that Pediococcus pentosaceus fermentation can effectively destroy allergen epitopes and mitigate the allergenicity of Tartary buckwheat.

The study of microbial diversity and volatile compounds in Tartary buckwheat sourdoughs.

Microorganisms play an essential role in forming volatile compounds in traditional staple products. Tartary buckwheat, as a medicinal and food material, has high nutritional value but its development and utilization are seriously restricted due to its poor flavor. In this study, 16S rRNA and ITS rRNA sequencing were used to analyze the microbial diversity of Tartary buckwheat sourdoughs, while HS-SPME-GC/MS was used to identify volatile compounds during fermentation. The results showed that Lactococcus and Weissella were the dominant bacterial genus. Wickerhamomyces, Penicillium, and Aspergillus were the main fungal genera in the Tartary buckwheat sourdoughs. And the main volatile compounds in Tartary buckwheat sourdough were pyrazine compounds. After 12 h of fermentation, a large amount of alcohol and esters were produced, which endowed the sourdough with a good flavor. This suggests that sourdough fermentation could significantly improve the flavor of Tartary buckwheat.

Pretreatment of buckwheat globulin by ultra-high pressure: Effects on enzymatic hydrolysis and final hydrolysate lipid metabolism regulation capacities.

The purpose of this study was to evaluate the effects of ultra-high pressure (UHP) pretreatment on the buckwheat globulin and the regulation of lipid metabolism disorder by its enzymatic hydrolysates (BGH). Buckwheat globulin hydrolysates pretreated by ultra-high pressure (UBGH) can significantly reduce the levels of total triglyceride (TG) and total cholesterol (TC) in model cells (MOD), significantly inhibit lipid accumulation and steatosis. In addition, UBGH can significantly reduce the content of malondialdehyde (MDA), increase the activity of total superoxide dismutase (T-SOD) and total antioxidant capacity (T-AOC), thus reducing the vicious cycle of lipid metabolism disorder caused by oxidative stress. RT-PCR and western blotting analysis showed that after UBGH intervention, compared with the MOD group, the mRNA expression levels of liver lipid and cholesterol metabolism related genes were significantly changed. UBGH significantly increased PPARα and LXRα and decreased SREBP2 mRNA expression. Therefore, UHP technology could enhance the regulatory effect of BGH on lipid metabolism disorder.