A food-grade self-nanoemulsifying delivery system for enhancing oral bioavailability of ellagic acid

Ellagic acid is known of a predominant bioactive component in pomegranate that possesses broad health benefits, but it has low bioavailability. In this work, we developed a food-grade self-nanoemulsifying system to improve the dissolution and absorption of ellagic acid. Solubility assay and pseudo-ternary phase diagrams revealed suitable components for the formulation. The optimal formulation was composed of polyethylene glycol, polysorbate, caprylic/capric triacylglycerol at the ratio of 45/45/10 wt.%. With this optimal formulation and gentle stirring, a fine nanoemulsion was achieved and had mean droplet size of around 120 nm. The dissolution of ellagic acid was significantly elevated with the formulation. Rat pharmacokinetics studies showed that ellagic acid was 6.6- and 3.2-fold more bioavailable with the formulation than with aqueous suspensions and pomegranate extract, respectively. The proposed self-nanoemulsifying system to deliver ellagic acid can be a novel strategy for developing products for dietary supplements and functional foods of ellagic acid. (C) 2017 Elsevier Ltd. All rights reserved.