Cyclodextrin-based metal organic frameworks as an ethylene scavenger: Recent advances, functional mechanisms, and...

Ethylene is a key plant phytohormone that governs fruit ripening and senescence, and its effective removal is essential to reducing postharvest losses across global fruit and vegetable supply chains. Although several ethylene-regulating packaging systems have been developed, many commercially available adsorbents are limited by toxicity concerns, non-biodegradability, low adsorption efficiency, and poor environmental compatibility. These limitations have aroused research interest in sustainable, food-safe alternatives. Metal-organic frameworks (MOFs), owing to their high surface area, tunable porosity, and structural versatility, have emerged as promising ethylene scavengers. However, the reliance of conventional MOFs on transition metals, toxic organic linkers, and energy-intensive synthesis routes restricts their application in food systems. Cyclodextrin-based MOFs (CD-MOFs) represent a rapidly emerging class of biocompatible porous materials derived from renewable carbohydrates, offering persistent porosity, high crystallinity, and inherent suitability for food-contact applications. This review critically examines the potential of CD-MOFs as next-generation ethylene scavengers for food packaging. It integrates the historical development and structural characteristics of cyclodextrins with an in-depth discussion of CD-MOF chemistry, synthesis strategies, and structure-function relationships governing ethylene adsorption. Particular focus is given on adsorption mechanisms and performance in shelf-life extension of fresh produce. Finally, current challenges related to stability, scalability, regulatory acceptance, and sustainable implementation are identified, and future research directions are proposed to facilitate the translation of CD-MOFs into practical food preservation solutions.