Effects-directed analysis of organic toxicants in wastewater effluent from Zagreb, Croatia.

The organic toxicants present in the effluent of the main sewer of the city of Zagreb, Croatia were isolated and identified through the use of effects-directed characterisation techniques. At the time of investigation, the wastewater effluent received no treatment and was comprised of a mixture of effluent from domestic and industrial sources. The organic load of the wastewater was isolated by solid phase extraction and toxicity profiles obtained using reverse-phase HPLC.

Total oxidant scavenging capacity of Euterpe oleracea Mart. (açaí) seeds and identification of their polyphenolic compounds.

The antioxidant capacity of methanol and ethanol seed extracts from Euterpe oleracea Mart. (açaí) against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was studied with the total oxidant scavenging capacity (TOSC) assay in a modified and automated version. Cold methanol digestion was the most efficient extraction method with respect to the antioxidant capacity.

Total oxidant scavenging capacities of Euterpe oleracea Mart. (Açaí) fruits.

The antioxidant capacities of 11 commercial and non-commercial samples of Euterpe oleracea Mart. (açaí) fruit pulp were studied with the total oxidant scavenging capacity assay in a modified and automated version against three reactive oxygen species. The antioxidant capacities of all purple açaí samples were found to be excellent against peroxyl radicals, good against peroxynitrite and poor against hydroxyl radicals compared with common European fruit and vegetable juices recently analysed.

Total oxidant scavenging capacities of common European fruit and vegetable juices.

The total oxidant scavenging capacity (TOSC) assay in a modified and automated version was applied for a comparative and detailed survey of the antioxidant capacities of 14 common European fruit and vegetable juices (ACE, apple, beetroot, blueberry, carrot, elderberry, lemon, lingonberry, multivitamin, orange, pink grapefruit, sauerkraut, and tomato juices as well as sour cherry nectar). The juices were ranked according to their scavenging capacity against the three reactive oxygen species (ROS) peroxyl and hydroxyl radicals and peroxynitrite. These ROS are of physiological and technological relevance and cover a broad range of reactivity.

Polymeric membranes for aromatic/aliphatic separation processes.

For the membrane-based separation of benzene/cyclohexane mixtures, the pervaporation properties of different 6FDA (4,4'-hexafluoroisopropylidene diphthalic anhydride) based copolyimide membranes have been investigated. In order to obtain high permeability as well as high selectivity copolyimides were synthesised using a combination of 4MPD (2,3,5,6-tetramethyl-1,4-phenylene diamine) and 6FpDA (4,4'-hexafluoro-isopropylidene dianiline) as well as DABA (3,5-diaminobenzoic acid) as monomers. Cross-linking is possible with this type of copolyimides and necessary to reduce swelling effects, which often occur with polymeric membranes and lead to a deterioration of the separation characteristics in aromatic/aliphatic separation processes.