Research Article Digestibility and Bioavailability of the Active Components of Erica australis L. Aqueous Extracts and Their Therapeutic Potential as Acetylcholinesterase Inhibitors Pilar Dias, 1 Pedro L. Falé, 1,2 Alice Martins, 1 and Amélia P. Rauter 1 1 Centro de Qu´ ımica e Bioqu´ ımica, Departamento de Qu´ ımica e Bioqu´ ımica, Faculdade de Ciˆ encias, Universidade de Lisboa, Edif´ ıcio C8, Campo Grande, 1749-016 Lisboa, Portugal 2 Institute of Pharmaceutical Science, King’s College London, 150 Stamford Street, London SE1 9NH, UK Correspondence should be addressed to Pedro L. Fal´ e; pedro.vieira fale@kcl.ac.uk and Alice Martins; aimartins@fc.ul.pt Received 30 April 2015; Revised 14 July 2015; Accepted 15 July 2015 Academic Editor: Nunziatina De Tommasi Copyright © 2015 Pilar Dias et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Erica australis L. (Ericaceae) is used in traditional medicine to treat many free-radical related ailments. In the present work, the stability and biological activity of the plant aqueous extracts submitted to an in vitro digestive process were investigated. Chemical stability was monitored by HPLC-DAD and LC-MS/MS, while the bioactivities were evaluated through the inhibition of acetylcholinesterase (AChE) and DPPH radical scavenging activity. Both extracts, whose main components were favonol glycosides, inhibited AChE, showing IC 50 values of 257.9 ± 6.2 g/mL and 296.8 ± 8.8 g/mL for the decoction and for the infusion, respectively. Signifcant radical scavenging activities were also revealed by both extracts, as denoted by the IC 50 values for the decoction, 6.7 ± 0.1 g/mL, and for the infusion, 10.5 ± 0.3 g/mL. Afer submission to gastric and pancreatic juices, no remarkable alterations in the composition or in the bioactivities were observed, suggesting that the extracts may pass through the gastrointestinal tract, keeping their composition and therefore their biological properties. Moreover, the bioavailability of the components of both extracts, as studied in a Caco-2 cell model, showed that compounds can permeate the membrane, which is a condition to exert their biological activities. Our results add further support to the potential of E. australis for its antioxidant and neuroprotective properties. 1. Introduction Erica species (Ericaceae) are used in folk medicine of many countries for their therapeutic properties such as antiviral [1], diuretic [2], anti-infammatory and antinociceptive [3], antioxidant [4, 5], antiulcer [6, 7], antimicrobial [8], hypolip- idaemic [9], analgesic [10], and cytotoxic [11] activities. Te fowers and aerial parts of Erica australis L. are used in the Tr´ as-os-Montes region (Portugal) to treat prostate, bladder, and kidneys diseases [12] while, in the Monte- muro mountains, the plant infusion is claimed to have anti-infammatory, diuretic, and sedative properties. Studies involving E. australis collected in Algarve were recently reported [13–15]. Tese authors determined the antioxidant and free-radical scavenging activities of diferent plant parts of Erica australis L. and the phenolic, favonoid, and amino acid profles of the leaves and fowers from this plant. In addition, the efects of the plant extracts on Caco-2 cells, fbroblasts, and selected pathogenic bacteria responsible for wound infection were also investigated, showing the potential of this plant as a source of bioactive ingredients that may provide a diversity of health benefts. Tese properties can be attributed to its chemical constituents, mainly phenolic acids, favonoids, amino acids, and anthocyanins [14, 16–20]. Te present work is focused on E. australis collected in the Montemuro region, Portugal, concerning the digestibility and bioavailability of the active components of the plant aqueous extracts and their therapeutic potential as acetyl- cholinesterase (AChE) inhibitors. Te stability of extracts under gastrointestinal conditions was evaluated by HPLC-DAD-MS/MS before and afer the submission to an in vitro digestion with artifcial gastric Hindawi Publishing Corporation Evidence-Based Complementary and Alternative Medicine Volume 2015, Article ID 854373, 7 pages http://dx.doi.org/10.1155/2015/854373