EVALUATION OF STABILITY AND TOXICITY OF NANOPARTICLES AS DELIVERY SYSTEMS OF BIOACTIVE SUBSTANCES IN DAIRY PRODUCTS

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Fundação para a Ciência e a Tecnologia

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Publications

Production of chitosan nanoparticles with polyphenols for incorporation in bioactive food formulations

Publication . Pereira, Adriana; Campos, Débora; Madureira, Ana Raquel; Pintado, Manuela

2014Conference object

Open access

Insights into the protective role of solid lipid nanoparticles on rosmarinic acid bioactivity during exposure to simulated gastrointestinal conditions

Publication . Madureira, Ana Raquel; Campos, Débora A.; Oliveira, Ana L.; Sarmento, Bruno; Pintado, M. E.; Gomes, Ana M. P.

The evaluation of the digestion effects on bioactive solid lipid nanoparticles (SLN) was performed. For this purpose, witepsol and carnauba SLN loaded with rosmarinic acid (RA) were exposed to the simulated gastrointestinal tract (GIT) conditions prevailing in stomach and small intestine. The simulation of intestinal epithelium was made with a dialysis bag and intestinal cell culture lines. Changes on SLN physical properties, RA release and absorption profiles were followed at each step. Combination of digestion pH and enzymes showed a significant effect upon SLN physical properties. Zeta potential values increased at stomach conditions and decreased at small intestine simulation. Also, at intestine, SLN increased their sizes and released 40-60% of RA, maintaining its initial antioxidant activity values. Sustained release of 40% of RA from SLN was also observed in dialysis tube. At CaCo-2 cell line, both types of SLN showed similar absorbed RA % (ca. 30%). Nevertheless, in CaCo-2/HT29x mix cell lines, for carnauba SLN a lower adsorption RA % was observed than for witepsol SLN. Solid lipid nanoparticles protected RA bioactivity (in terms of antioxidant activity) until reaching the intestine. A controlled release of RA from SLN was achieved and a significant absorption was observed at intestinal cells. Overall, SLN produced with witepsol showed a higher stability than carnauba SLN.

2016Journal article

Restricted access

Fermentation of bioactive solid lipid nanoparticles by human gut microflora

Publication . Madureira, Ana Raquel; Campos, Débora; Gullon, Beatriz; Marques, Cláudia; Rodríguez-Alcalá, Luís M.; Calhau, Conceição; Alonso, Jose Luis; Sarmento, Bruno; Gomes, Ana M.; Pintado, M. E.

Solid lipid nanoparticles (SLNs) can be used for oral delivery of phenolic compounds in order to protect them from the harsh conditions of digestion and improve their bioavailability in the intestinal epithelium. Recently, the production and characterization of SLNs loaded with rosmarinic acid (RA) and herbal extracts was performed for future use as functional food ingredients. Diet components have been shown to have a huge impact on gut microbiota viability and metabolic activity. Hence, SLNs loaded with RA, sage and savoury extracts have been evaluated for their effect on intestinal microbiota growth and the metabolic products generated. Fermentations in anaerobic batch cultures using volunteer human faeces were performed during 24 h. Dynamic bacterial population changes were analysed using PCR-real time, as well as the generation of fatty acids and the quantification of phenolic compounds by analytical methods. Solid lipid nanoparticles released phenolic compounds at non-inhibitory bacterial growth concentrations. Released herbal extract phenolic compounds showed a beneficial effect on gut microbiota growth (e.g. bifidogenic effects) and were used as substrates. Acetate, formate, lactate and butyrate were produced in higher concentrations. The released phenolic compounds also induced PUFA and trans fatty acids metabolic activity, the production of saturated fatty acids, as well of potential beneficial conjugated linoleic acid isomers. Solid lipid nanoparticles modulate gut microbiota and metabolic activities.

2016-01Journal article

Restricted access