The resource utilization of food industry wastes is of great significance. This study aimed to prepare a novel polysaccharide from sea buckthorn pomace, and investigate its structural features and lipid-lowering potential. The homogeneous polysaccharide, designated as D2N1, consisted of arabinose, galacturonic acid, galactose, glucose, mannose, rhamnose, glucuronic acid and fucose in a molar ratio of 70.12%: 11.74%: 6.60%: 4.40%: 2.93%: 2.93%: 0.79%: 0.49%, with the average molecular weight of 8.839 kDa. The backbone was composed of α−L−Araf−1→4−α−D−GalpA−1→4−β−D−Galp−1→5−α−L−Araf−(1→residues, with a terminal α-L-Araf-(1 → attached to O-5 of the 5-linked Araf and a single α-D-Glcp-(1 → side chain attached to O-2 of the 2,5-linked Araf. D2N1 presented a wrinkled sheet-like shape with uniform surface protrusions. Functionally, D2N1 attenuated lipid accumulation and oxidative stress in OA-induced HepG2 cells. This study highlights the potential of D2N1 as a candidate functional food ingredient and contributes to the high-value utilization of sea buckthorn residues.
Postharvest flavour evolution in peach fruit depends on coordinated changes in volatile and non-volatile metabolites, but these processes remain unclear in cultivars with contrasting flesh textures. Here, the melting flesh cultivar ‘Hujingmilu’ (‘HJ’) and the stony hard cultivar ‘Xiacui’ (‘XC’) were stored at 12 °C for 21 d. E-nose, E-tongue, GC–MS, HPLC, and LC-MS/MS analyses were integrated to characterize aroma, taste, VOCs, sugars, organic acids, amino acids, and their derivatives. ‘HJ’ and ‘XC’ showed distinct flavour trajectories during storage. ‘HJ’ was characterized by lactone accumulation, especially γ-hexalactone, γ-decalactone, γ-dodecalactone, and δ-decalactone, contributing to ripe peach-like aromas. ‘XC’ maintained higher esters, alcohols, aldehydes, and terpenoids, exhibited stronger malic acid-associated sourness, and showed amino acid changes, including GABA accumulation and changes in glutamate-related metabolites. These findings reveal cultivar-specific flavour divergence and support targeted postharvest storage strategies for peach fruit.
Quercetin is a widely occurring dietary flavonol with documented health effects. It can be obtained from a range of plant sources, synthesized chemically, and generated through microbial biosynthesis in engineered bacterial hosts. Upon ingestion, quercetin is absorbed mainly via passive transcellular diffusion across the intestinal epithelium, while unabsorbed fractions reach the colon. The absorbed quercetin undergoes Phase II conjugation catalyzed by UGTs (UDP-glucuronosyltransferases), SULTs (sulfotransferases), and COMT (catechol-O-methyltransferase) in the liver and intestine, generating circulating conjugates. In the colon, unabsorbed quercetin bidirectionally interacts with the microbiota. It reduces LPS-producing Gram-negative bacteria, promotes short-chain fatty acid production, and modulates bile acid and tryptophan metabolism. Conversely, gut microbiota cleave the quercetin C-ring and perform secondary modifications (dehydroxylation, decarboxylation, and methylation) to generate bioactive phenolic catabolites, which exhibit multiple activities. Understanding the sources, absorption, metabolism, and gut microbiota interactions of quercetin is essential for optimizing its therapeutic and nutritional applications.
