Electrospun nanofibrous film co-loaded with thymol/thiabendazole hydroxypropyl-β-cyclodextrin inclusion complexes: humidity-triggered release and edible fungi preservation application

Electrospun CS/PVA films with THY/TBZ@HPβCD ICs enabled humidity-gated preservation. • Synchronized dual-release of THY/TBZ at 93% RH via non-Fickian transport. • Films exhibited 94.2% ABTS scavenging and synergistic antibacterial efficacy. • Shiitake browning index dropped from 74.4% to 43.2% with minimal weight loss. • Humidity-triggered release suppresses PPO melanization. The intense postharvest respiration of edible fungi rapidly establishes a near-saturated humidity microenvironment that accelerates microbial spoilage and PPO-associated browning. To harness this detrimental moisture as an intrinsic trigger, we developed a humidity-gated electrospun nanofibrous film by co-loading two individually prepared inclusion complexes (THY@HPβCD and TBZ@HPβCD) into a chitosan/ poly(vinyl alcohol) (CS/PVA) matrix (TTIC-CP). The film exhibited enhanced wettability and robust physicochemical properties, enabling relative humidity (RH)-triggered synchronized co-release of both actives. Under 93% RH, cumulative release reached 88.07% (THY) and 87.30% (TBZ), and kinetic fitting indicated non-Fickian transport governed by coupled diffusion and matrix relaxation/erosion. Checkerboard assays further confirmed THY-TBZ synergy against E. coli , S. aureus and P. tolaasii with minimum FICI values of 0.50, 0.38 and 0.50. Accordingly, 8TTIC-CP delivered strong antioxidant activity (94.17% ABTS scavenging efficiency at 650 s) and effective antibacterial protection (75.63% inhibition against P. tolaasii ). In shiitake packaging, 8TTIC-CP markedly delayed browning and quality loss, reducing the browning index from 74.37% (control) to 43.17% and lowering weight loss to 4.77%, while alleviating oxidative and enzymatic browning responses. Comparable preservation efficacy was also confirmed in Oudemansiella raphanipes and Stropharia rugosoannulata . This work provides a practical humidity-gated dual-active packaging strategy for high-respiration edible fungi and related fresh produce. Download: Download high-res image (129KB) Download: Download full-size image