The structure-bioactivity relationship of Tremella fuciformis polysaccharides (TFPs) in anti-aging in vivo is rarely reported. In the present study, a purified TFP, named HM, mainly composed of mannose, fucose, xylose, and glucose in a molar ratio of 4.14:0.98:0.81:0.62, was obtained from the...

The increasing global demand for sustainable hydrocolloids has positioned passion fruit peel as a strategic alternative to traditional citrus and apple sources, owing to the associated unique molecular composition, which is rich in rhamnogalacturonan-I (RG-I). However, important gaps remain in understanding how extraction-induced structural modifications influence specific nutritional outcomes. This review critically assesses the effects of novel green extraction methods, including ultrasonic, microwave, and enzyme-assisted techniques, on the extraction efficiency, molecular integrity, and degree of branching of passion fruit peel pectin (PFPP). In contrast to prior primarily descriptive compilations, this review analyzes available data to elucidate relationships between the fine structure of PFPP (e.g., degree of esterification) and the associated metabolic pathways in the intestine. Specifically, this review explores the effects of PFPP on the gut microbiota composition and short-chain fatty acid production, and proposes future research directions based on these findings. Additionally, we highlight challenges associated with industrial-scale PFPP production, including technical limitations and equipment costs, and offer recommendations for improvement. This review provides a new perspective for developing targeted prebiotic carbohydrates, transcending mere waste utilization toward precise nutritional interventions.

Tylorrhynchus heterochaetus is an aquatic food with both edible and medicinal value in China. With a protein-rich body wall, it has strong potential for producing bioactive peptides. To explore its potential as a source of immunomodulatory peptides, in this study, flavor enzymes were selected as the optimal hydrolases, and the hydrolyzed products were subjected to ultrafiltration fractionation. The <3000 Da portion exhibited the most effective immune-stimulating activity in RAW 264.7 macrophages, enhancing phagocytosis and promoting the secretion of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and nitric oxide (NO) in a concentration dependent manner. Peptide omics analysis, combined with the activity and safety screened by bioinformatics, identified 43 candidate peptides. Molecular docking predicts that three novel peptides, LPWDPL, DDFVFLR and LPVGPLFN, exhibit strong binding affinity with toll-like receptor 4/myeloid differentiation factor-2 (TLR4/MD-2) receptors through hydrogen bonding and hydrophobic/π stacking interactions. Synthetic verification confirmed that these peptides were not only non-toxic to cells at concentrations ranging from 62.5 to 1000 µg/mL, but also effective in activating macrophages and stimulating the release of immune mediators. This study successfully identified the specific immunomodulatory peptides of the Tylorrhynchus heterochaetus, supporting its high-value utilization as a natural source of raw materials for immunomodulatory functional foods.