Allergy can cause intestinal damage, including through cell apoptosis. In this study, intestinal cell apoptosis was first observed in the β-conglycinin (β-CG) allergy model, and the effect of Lactobacillus rhamnosus GG (LGG) on reducing apoptosis of cells in the intestine and its underlying mechanisms were further investigated. Allergic mice received oral LGG daily, and intestinal tissue apoptotic cells, gut microbiota, and metabolites were evaluated six and nine days after intervention. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) analysis revealed that LGG intervention could reduce the incidence of cell apoptosis more effectively than natural recovery (NR). The results of 16S rRNA analysis indicated that LGG intervention led to an increase in the relative abundance of Bacteroides. Metabolite analysis of intestinal contents indicated that histamine, N-acetylhistamine, N(α)-γ-glutamylhistamine, phenylalanine, tryptophan, arachidonic acid malate, and xanthine were significantly decreased, and deoxycholic acid, lithocholic acid were significantly increased after the LGG intervention on β-CG allergy; the decreases in histamine and N(α)-γ-glutamylhistamine were significant compared with those of NR. In conclusion, LGG reduces apoptosis of cells induced by β-CG allergy, which may be related to regulation of Bacteroides and the bile secretion pathway.

Previous studies have shown that advanced glycation end products (AGEs) are implicated in the occurrence and progression of numerous diseases, with dietary AGEs being particularly associated with intestinal disorders. In this study, methylglyoxal-beta-lactoglobulin AGEs (MGO-β-LG AGEs) were utilized as the exclusive nitrogen source to investigate the interaction between protein-bound AGEs and human gut microbiota. The high-resolution mass spectrometry analysis of alterations in peptides containing AGEs within metabolites before and after fermentation elucidated the capacity of intestinal microorganisms to enzymatically hydrolyze long-chain AGEs into short-chain counterparts. The 16S rRNA sequencing revealed Klebsiella, Lactobacillus, Escherichia-Shigella, and other genera as dominant microbiota at different fermentation times. A total of 187 potential strains of AGE-metabolizing bacteria were isolated from the fermentation broth at various time points. Notably, one strain of Klebsiella exhibited the most robust growth capacity when AGEs served as the sole nitrogen source. Subsequently, proteomics was employed to compare the changes in protein levels of Klebsiella X15 following cultivation in unmodified proteins and proteins modified with AGEs. This analysis unveiled a remodeled amino acid and energy metabolism pathway in Klebsiella in response to AGEs, indicating that Klebsiella may possess a metabolic pathway specifically tailored to AGEs. This study found that fermenting AGEs in healthy human intestinal microbiota altered the bacterial microbiota structure, especially by increasing Klebsiella proliferation, which could be a key factor in AGEs’ role in causing diseases, particularly intestinal inflammation.

The accumulation of dietary advanced lipid oxidation end-products (ALEs) in thermally processed meat products is closely associated with quality deterioration and potential health risks. Spices are widely recognized for both flavoring and antioxidant properties and may therefore help reduce ALEs formation, yet their comparative and dose-dependent effects remain insufficiently defined. In this study, roasted beef patties were used as a model food to systematically evaluate the effects of dried tangerine peel, cinnamon, clove, and rosemary, each individually added at 0.1%, 0.5%, and 1.0% (w/w), on product quality, ALEs formation and the accumulation of ALEs precursors. Pearson correlation analysis and principal component analysis were further applied to explore the relationships among spice antioxidant properties, carbonyl precursor accumulation, and ALE-associated fluorescence. The results showed that the four spices had no significant effect on cooking loss but influenced color and, to a lesser extent, texture attributes. Their inhibitory effects on ALEs formation differed substantially. Clove and rosemary showed stronger and more stable inhibition, particularly at 0.5% and 1.0% addition levels. Precursor analysis showed that clove and rosemary markedly reduced malondialdehyde (MDA) accumulation, whereas glyoxal and methylglyoxal exhibited more variable responses among treatments. Changes in MDA were more consistent with those in ALE-associated fluorescence. Clove exhibited the highest total phenolic and flavonoid contents and overall antioxidant potential. Integrated analysis further indicated that stronger antioxidant properties were associated with lower MDA levels and ALE-associated fluorescence. However, the relatively strong in vitro antioxidant activity of cinnamon did not translate into stronger inhibition in the beef patty matrix, suggesting that antioxidant capacity alone could not fully explain the spice-dependent effects. Overall, clove and rosemary at 0.5–1.0% (w/w) were the most promising treatments for mitigating fluorescent ALE-associated product formation in roasted beef patties.