Maltodextrine nanoparticles loaded with polyphenolic extract from apple industrial waste: preparation, optimization and characterization

The main aim of this study was to prepare apple pomace polyphenolic extract (APPE- referred to as a core) loaded into biodegradable and commercially available natural polymer such as maltodextrin (MD-referred to as a shell). The polymer coating potentially improves its low stability and bioavailability and also directs the control release of the encapsulated material. The MD-nanoparticles (NPs) loaded with the APPE were prepared by a modified nanoprecipitation method. An experimental central composite design was utilized for the modeling, optimization and to assess the influence (and interactions) of the shell to core ratio, surfactant concentration, and sonication time (as the independent variables) on the NPs preparation to maximize the level of polyphenols loading and the NPs formation yield (referred to as dependant variables). The adopted models were verified statistically and experimentally. The results showed that amongst the independent variables, the shell to core ratio and the surfactant concentration were statistically significant in the experimentally selected ranges. By adopting the optimal process conditions, the spherical shaped NPs were prepared with a mean average size of 52 nm (confirmed by the Dynamic Light Scattering and FE-SEM techniques) and polyphenols loading efficiency of 98%. FT-IR spectroscopy confirmed the successful entrapment of the core in the shell of NPs. Hydrogen bonding is one of the modes of interactions between the hydrophilic moieties of polyphenols and MD. The in vitro polyphenols release of the NPs through simulating cancerous tumor acidity conditions represented a sustainable release, indicating potential anticancer application of the NPs

Food industry by-products valorization and new ingredients: cases of study

The concern about food and beverages is gaining importance for the general public in terms of health and more environmentally sustainable food products. Healthy foods imply the awareness on their safety, nutritional characteristics, and the potential inclusion of nutritive complements such as antioxidants, vitamins, and proteins, which promote a benefit to the consumer's health. Also, organic foods, with less added chemicals such as pesticides, are more demanded recently. The environmentally sustainable food production has to reconsider the wastes as by-products that can be transformed to provide valuable compounds (antioxidants, fiber, fuels, etc.) that could be used as new products or raw materials in the food industry or even applied in other sectors such as pharmaceutical, polymer, and energy industries. In this chapter, selected successful case studies in which food wastes are transformed into new products by using different separation and purification technologies will be shown. Furthermore, the use of different wild vegetables from natural environments as a source of valuable compounds and new ingredients will be described.info:eu-repo/semantics/publishedVersio

Ligand design for metal catalysed reactions in supercritical carbon dioxide

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Formation and catalytic activity of Pd nanoparticles on silica in supercritical CO2

Metal complexes of polydimethylsiloxane-derived ligands can be adsorbed onto silica and subsequently reduced in-situ in supercritical CO2 (scCO2) to generate metal nanoparticles. Pd nanoparticles on silica, generated during C–C coupling reactions in scCO2, can be recycled several times without any loss in activity. Focusing on Heck and Suzuki coupling reactions, the products showed no contamination of the organic products with Pd using quantitative ICP emission spectroscopy. The use of scCO2 prevents the desorption of the Pd nanoparticles from their support. Build-up of ammonium salts as by-products in these coupling reactions leads to reduced activity for these heterogeneous catalysts after four runs

Room temperature aerobic oxidation of alcohols using CuBr2 with TEMPO and a tetradentate polymer based pyridyl-imine ligand

A series of tetradentate pyridyl-imine terminated Schiff-base ligands has been investigated for their ability in the catalytic oxidation of alcohols when combined with copper bromide (CuBr2) and 2,2,6,6-tetramethylpiperidyl-1-oxy (TEMPO). Analogous bidentate ligands showed poorer catalytic activity and the ratio of Cu:ligand was of crucial importance in maintaining high yields. The polydimethylsiloxane (PDMS) derived pyridyl-imine terminated ligand combined with copper (II) ions affords an effective and selective catalyst for aerobic oxidations of primary and secondary alcohols under aqueous conditions. Preliminary mechanistic studies suggest that bimetallic complexes may be playing a role in the catalytic transformation