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The interest in separating and concentrating bioactives and minerals from seaweeds extracts is growing due to large health benefits of these substances. The aim of this study was to investigate the separation of components of Fucus vesiculosus seaweed extracts by tangential ultrafiltration and apply Hermia's models adapted to crossflow ultrafiltration to understand the fouling mechanism. The influence of membrane cut-off varying from 5 to 150 kDa, crossflow velocity from 0.081 to 0.095 m/s and transmembrane pressure between 2 and 8 bar was studied. The present study revealed that the ultrafiltration membranes process was successful in clarifying and still delivering permeates with a high content in iodine. Clarification was almost completely achieved with 5 kDa polyethersulfone membrane, while the hydrophilic polyethersulfone membrane was not adequate to due to the high retention in iodine. Cake layer formation mathematical model was successfully used to predict the permeate flux over time. There was evidence that cake layer is the fouling mechanism in the filtration of Fucus vesiculosus extracts, whatever the membrane crossflow velocity or transmembrane pressure, probably due to the high content of these extracts in alginates. [ABSTRACT FROM AUTHOR]

In this study, an ethanolic extract from Portuguese propolis was prepared, fractionated by high-performance liquid chromatography, and the identification of the phenolic compounds was done by electrospray mass spectrometry in the negative mode. This technical approach allowed the identification of 37 phenolic compounds, which included not only the typical phenolic acids and flavonoids found in propolis from temperate zones but also several compounds in which its occurrence have never been referred to in the literature. Four of the novel phenolic compounds were methylated and/or esterified or hydroxylated derivatives of common poplar flavonoids, although six peculiar derivatives of pinocembrin/pinobanksin, containing a phenylpropanoic acid derivative moiety in their structure, were also identified. Furthermore, the Portuguese propolis sample was shown to contain a p-coumaric ester derivative dimer. [ABSTRACT FROM AUTHOR]

The preparation of table olives according to the Italian traditional “Ferrandina” method (Fer) includes an initial blanching step of black Cassanese olives, followed by salting and oven-drying. Its industrial implementation, also called the “Sybaris” method (Syb), replaces the blanching procedure by cutting the olives followed by immersion in water. The measurement of tensile properties showed that the Fer processing increased the weakness, softness, and deformability of the skin and the flesh of olive fruits, while the flesh of the Syb fruits became stronger and stiffer. These differences are probably correlated to the degradation and/or reorganisation of cell wall polysaccharides in the fruits. The degradation of pectic and hemicellulosic polysaccharides in the Fer olives was inferred by their increased solubility in aqueous solutions. Contrarily, retention of pectic polysaccharides was observed in Syb olives. As no correlation was found between cell wall degrading enzymatic activities and cell wall polysaccharides extractability, it is probable that these modifications were driven by heat. [ABSTRACT FROM AUTHOR]