Akademik Veri Yönetim Sistemi
Food Bioscience, cilt.74, 2025 (SCI-Expanded)
This study investigated Lacticaseibacillus casei SNUT1, a selenium-tolerant strain isolated from fermented foods of the Qinba region in China, with the aim of addressing the dual challenges of selenium supplementation and nanoplastic detoxification. The strain exhibited high selenite resistance (MIC: 5 mM) and achieved a bioaccumulation efficiency of 82.3 %. Genomic analysis confirmed the presence of conserved selenium resistance genes (selD, cysK) and revealed the upregulation of oxidative stress response genes (sodA ↑2.3-fold, katA ↑3-fold, glutathione reductase ↑81 %), supporting the efficient biotransformation of selenite into elemental selenium (93.5 %). Extracellular vesicle–nanoselenium complexes (EVNS) were purified and characterized as monodisperse crystalline Se0 nanoparticles (85.6 ± 3.2 nm, zeta potential −32.5 mV) stabilized by vesicle-derived proteins, confirming that the biologically engineered nanostructure has high colloidal stability. Functionally, selenium-enriched SNUT1 demonstrated preferential antimicrobial activity against gram-negative bacteria (e.g., E. coli, inhibition zone: 2.52 ± 0.02 cm) and exhibited enhanced antioxidant capacity (DPPH: 80.57 ± 0.38 %), largely attributed to extracellular selenometabolite secretion. In murine models, biosynthesized nanoselenium (SeNPs) outperformed inorganic selenite by significantly reducing systemic inflammation (IL-1β ↓63 %), oxidative stress (MDA ↓58 %), and intestinal permeability (FITC-dextran ↓51 %) while promoting probiotic microbiota enrichment and increasing butyrate production (↑1.8-fold). Furthermore, SeNPs mitigated nanoplastic-induced toxicity by scavenging reactive oxygen species and suppressing NF-κB signaling, leading to the restoration of microbial SCFA profiles and tryptophan metabolism. Multiomics analysis revealed the involvement of SeNPs in both selenocompound metabolism and glutathione recycling, in contrast with the prodysbiotic effects observed with selenite treatment. Integrated multiomics revealed that SeNPs engage both selenocompound metabolism and glutathione recycling, in sharp contrast to the prodysbiotic and pro-oxidative effects observed with selenite. In conclusion, this work bridges a critical research gap by establishing a bioinspired microbial strategy for safe selenium biotransformation and concurrent nanoplastic detoxification. These findings position L. casei SNUT1 and its biogenic SeNPs as promising agents for functional food development, gut microbiota modulation, and nanopollutant mitigation, providing a sustainable avenue for nutritional and environmental health applications.