Double-layer electrospun fibers with integrated gas-selective and bioactive functions for the preservation of perishable fruit.

Respiration is the primary driver of postharvest deterioration in highly perishable fruits, as both plant tissues and associated microorganisms rapidly consume available nutrients and accelerate quality loss. Modulating the surrounding gaseous environment is therefore critical for mitigating respiration-the most important factor of driving spoilage. In this study, double-layer fiber films with selective gas permeability were developed to regulate O2 and CO2 levels within localized microenvironments. Their asymmetric structure established a mildly hypoxic and CO2-enriched atmosphere, achieving a gas selectivity of 11.39 ± 0.88 and effectively lowering respiratory intensity. The fibers also provided antibacterial and antioxidative functions, contributing to reduced microbial contamination and oxidative degradation. When applied to litchi, the films extended the effective commercial shelf life to approximately 9 days and significantly delayed overall spoilage throughout a 15-day evaluation period under controlled storage conditions. Beyond their demonstrated efficacy, these fibers show considerable potential for advancing food preservation strategies, offering meaningful opportunities for more sustainable packaging solutions. Their dual-action mechanism-integrating gas regulation with biological active-positions them as a versatile material platform for addressing spoilage challenges in highly perishable fruits.