a Zhejiang University Tea Research Institute , Hangzhou , China.
b CSIRO Agriculture & Food , 671 Sneydes Road, Werribee , Victoria , Australia.
Crit Rev Food Sci Nutr. 2019;59(10):1563-1579. doi: 10.1080/10408398.2017.1422110. Epub 2018 Jan 18.
Catechins, present in many fruits and vegetables, have many health benefits, but they are prone to degradation. Nano- and micro-particle systems have been used to stabilise catechins when exposed to adverse environments and to improve their bioavailability after ingestion. This review discusses the inherent properties of various catechins, the design of delivery formulations and the properties of catechin-loaded nano- and micro-particles. The protection afforded to catechins during exposure to harsh environmental conditions and gastrointestinal tract transit is reviewed. The bioavailability and efficacy of encapsulated catechins, as assessed by various and conditions, are discussed. Bioavailability based on uptake in the upper gut alone underestimates the bioavailability as polyphenols. The caveats with interpretation of bioavailability based on various tests are discussed, when taking into consideration the pathways of catechin metabolism including the role of the gut microflora. However, taken together, the weight of the evidence suggests that there are potentially improved health benefits with the use of appropriately designed nano- and micro-particles for delivery of catechins. Further systematic studies on the metabolism and physiological effects of encapsulated catechins and clinical trials are needed to validate the bioefficacy of the encapsulated catechins.
儿茶素存在于许多水果和蔬菜中，具有许多健康益处，但它们容易降解。纳米和微粒子系统已被用于在暴露于恶劣环境时稳定儿茶素，并提高摄入后的生物利用度。本文综述了各种儿茶素的固有特性、递送制剂的设计以及载有儿茶素的纳米和微粒子的特性。讨论了儿茶素在暴露于恶劣环境条件和胃肠道转运过程中的保护。通过各种 和 条件评估了包封儿茶素的生物利用度和功效。仅基于上消化道吸收来评估生物利用度会低估多酚的生物利用度。讨论了基于各种测试的生物利用度解释的注意事项，同时考虑了儿茶素代谢途径，包括肠道微生物群的作用。然而，总的来说，有证据表明，使用适当设计的纳米和微粒子来递送儿茶素可能会带来潜在的改善健康益处。需要进一步进行关于包封儿茶素的代谢和生理作用的系统研究和临床试验，以验证包封儿茶素的生物功效。
