Trends in Food Science & Technology

Contents lists available at ScienceDirect

journal homepage: www.elsevier.com/locate/tifs

Colon-targeted delivery systems for nutraceuticals: A review of current vehicles, evaluation methods and future prospects ∗ Kun Fenga, Yun-shan Weia, Teng-gen Hub, Robert J. Linhardtc, Min-hua Zonga, Hong Wua, a School of Food Science and Engineering, South China University of Technology/Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Guangzhou, 510640, China b Sericultural & Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Aﬀairs /Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou, China c Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA

ARTICLE INFO ABSTRACT

Keywords: Background: Advances in nutriology have suggested the colon as a superior site for nutrition absorption. Colon targeting Nutraceuticals, including phytochemicals, probiotics, etc., have received great attention owing to their health- Nutraceuticals promoting functionalities for colon. However, these compounds generally exhibit poor solubility or are sensitive Vehicles to the harsh environment of food processing and gastrointestinal tract, thus, lowering their bioavailability and Evaluation methods compromising their envisioned benefits. Therefore, there is a need to develop suitable delivery systems to protect active agents from these severe conditions and to maintain their functions in the colon. Scope and approaches: Colonic delivery of nutraceuticals has emerged as a new impetus for researchers interested in developing functional foods. This review presents an overview mainly about current studies relevant to different colon-targeted vehicles for nutraceuticals. The physiological conditions of colon and the corresponding principles for constructing vehicles are first reviewed to better understand the mechanisms of different vehicles. Relevant methods for evaluating the efficiency of vehicles are also summarized. Last, current limitations and the future scope for the colonic delivery of nutraceuticals are identified and addressed. Key findings and conclusions: Recently, significant progress has been made in colon-targeted delivery of nutraceuticals and different evaluation methods were applied to assess the efficacy of vehicles. However, advances in the colonic delivery of nutraceuticals are still in their early stages and multi-unit vehicles with great efficacy need to be further investigated. Furthermore, to fully mimic the real conditions of gastrointestinal tract, more systematic and precise in vitro/vivo testing should be explored to make sure that a fully function of nutraceuticals enters the colon.

1. Introduction has been shown many advantages, including minimizing systemic side eﬀects, improving bioavailability, and delivering the drugs in their in- Advances in the nutrition and metabolism have promoted a deep tact forms (Kumar, Ali, Kaldhone, Shirode, & Kadam, 2010; Kumar, understanding of the interactions between the human health and the Chandra, & Gautam, 2013). However, the application of these advances colon. Recently, the colon has been regarded as the ideal absorption site to the food industry is still in its early stages. As is known that the for improving the bioavailability of functional agents due to the distinct bioavailability of bioactive components is the main factor that must be advantages the colon presents, such as its near neutral pH, long transit considered in designing functional foods. Therefore, the colonic de- time, and reduced enzymatic activity (Amidon, Brown, & Dave, 2015). livery of bioactive compounds has emerged as a new goal for re- In this regard, oral, colon-targeted delivery systems have been put sea