Directed co-assembly of binary natural small molecules into carrier-free sprayable gel with synergistic multifunctional activity for perishable fruits preservation

The rotting of fresh fruits is a great challenge in the food industry for the whole world, which also easily result in more severe social problem such as food shortages, environmental pollution and health hazards. Microbial contamination is the main cause of fruits rotting, but cannot be solved by conventional methods like waxing, refrigeration, or vacuum packaging currently. Leveraging the multiple bioactivities and unique assembly function of natural small molecules, we have firstly achieved the directed co-assembly of binary natural small molecules (resveratrol and piceid) into a carrier-free gel by a simple heat-cooling method for perishable fruits preservation. It was proven that hydrogen bonding and π-π stacking interactions were the main driving forces for the co-assembly of binary molecules. And Res-Pic gel had been demonstrated to possess synergistic antioxidant, antibacterial, and biofilm removal properties compared to corresponding monomer. After sprayed on the surface of fruits, it was found to significantly inhibit microbial reproduction, prevent browning, reduce water and nutrient loss. Especially it had realized to ultimately decrease the corruption rate by 36.81% of cherries comparing with the untreated group during storage at room temperature. Furthermore, experimental study in vivo showed its excellent biocompatibility, thus avoiding the health risk from mis-eating. Such a directed co-assembly strategy based on binary NSMs have provided a simple, low-cost, biosafe gel products with enhanced biological activity, and further showed great prospects for perishable food preservation.