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The ITQB NOVA community celebrated 30 years of integration into NOVA University Lisbon

The main objective of this project was to valorise the cactus Opuntia, which spontaneously grow in the south of Portugal, through the development of clean processes for the isolation of extracts/concentrates that could be considered functional ingredients, with high positive biological activities and with potential application in emergent industries, such as the nutraceuticals, nutricosmetics and cosmeceuticals and functional agro-food products. Within the activities developed, it was possible to extend the knowledge about Opuntia cactus, namely about some varieties that grow in Alentejo, Algarve and Ribatejo and to obtain a set of results that scientifically support their bioactivity. The different skills of the team involved, namely in Analysis of natural products, Processing and extraction of bioactive compounds from plants, Bioactivity evaluation, Metabolism and pharmacokinetics, allowed the accomplishment of the multisciplinary work program planned in the proposal. The several activities developed included the i)selection, collection and identification of harvested samples, ii) isolation of bioactive extracts through the application of clean technologies, such as use of biocompatible solvents (eg. water and ethanol), supercritical fluid CO2 and pressurised-solvent extraction and/or separation/filtrations using selective membranes processes, iii)Evaluation of cytotoxicity and application of specific bioactivity tests to testify biofunctionality (positive effects for human health, namely antioxidant, anti-inflammatory and antiproliferative activities. All the samples studied were submitted to analytical characterisation, oriented to the identification and quantification of specific compounds responsible for the bioactive responses. In some cases, permeability and interaction studies were also performed. The components of isolated extracts were evaluated in terms of their stability, ability to withstand digestion conditions. To tackle bioavailability and stability problems and to obtain different forms compatible with different applications, the active ingredients were further processed through size reduction (micronization/pulverization) and/or preparation of adequate delivery systems. Final formulations were optimized in terms of stability/shelf-life, solubility/ bioavailability, compatibility with target final products. The team involved in this work expects that the results obtained (disseminated in the form of MSc thesis , scientific journals with peer revisions and in a thematic workshop planned for the first trimester of 2014,in Lisbon ) deliver arguments for the promotion of the Opuntia agriculture and marketing of the developed functional derived products.

João Marques, Bacterial Signalling Laboratory

Nicolas Bernier, Coordination and Supramolecular Chemistry Lab