Cyclodextrin-based metal-organic frameworks as microreactors: Purification and stabilization of food bioactive compounds in Confined Spaces

Functional foods of bioactive compounds are generally biologically and physiologically active, providing health-beneficial effects. Their structure sensitivity to various environmental and processing conditions makes it hard to utilize them in food systems. Cyclodextrin-based metal-organic frameworks (CD-MOFs) are proposed as multifunctional materials that can separate and stabilize bioactive compounds. These materials have excellent biocompatibility, an eminently porous structure, and various functional sites. This review discusses the important factors of structure features of CD-MOFs including ion-exchange properties, host-guest interactions, diverse porous structure, and controllable particle size, which have a key role in the encapsulation properties of bioactive compounds. In addition, the recent progress in the development of CD-MOFs for the separation and stabilization of bioactive compounds in food applications has been summarized and discussed. By taking advantage of the pore structure of CD-MOFs, CD-MOFs have the potential for selective capture of bioactive compounds from food sources. In addition, food bioactive compounds encapsulated in CD-MOFs can protect against external condition damage by pore shielding effect of CD-MOFs. Although CD-MOFs are promising for the purification and stabilization of food bioactive compounds, the precise control over pore surface chemistry and pore size of CD-MOFs should be delicately designed for maximally selective enrichment and stabilization of food bioactive compounds.