Sequential two-column electro-Fenton-photolytic reactor for the treatment of winery wastewater

The high amount of winery wastewaters produced each year makes their treatment a priority issue due to their problematic characteristics such as acid pH, high concentration of organic load and colourful compounds. Furthermore, some of these effluents can have dissolved pesticides, due to the previous grape treatments, which are recalcitrant to conventional treatments. Recently, photo-electro-Fenton process has been reported as an effective procedure to mineralize different organic contaminants and a promising technology for the treatment of these complex matrixes. However, the reactors available for applying this process are scarce and they show several limitations. In this study, a sequential two-column reactor for the photo-electro-Fenton treatment was designed and evaluated for the treatment of different pesticides, pirimicarb and pyrimethanil, used in wine production. Both studied pesticides were efficiently removed, and the transformation products were determined. Finally, the treatment of a complex aqueous matrix composed by winery wastewater and the previously studied pesticides was carried out in the designed sequential reactor. The high removals of TOC and COD reached and the low energy consumption demonstrated the efficiency of this new configuration.

Trypsin digestion of arginase: evidence for a stable conformation manganese directed

1. Controlled tryptic digestion of native arginase from rat liver suggests that Mn2+ promotes a stable conformation as shown by the following features. 2. An 18-fold increase in the half-life of arginase activity in the presence of Mn2+ is produced. 3. The stability of subunit B of arginase is increased in the presence of Mn2+ as revealed by SDS-PAGE during the time-course of trypsin cleavage. 4. The different digestion products of arginase with and without Mn2+ appearing during the time-course of tryptic treatment. 5. Different activity/bands protein ratio at any time of the tryptic digestion in the incubation mixtures, with and without Mn2+, are apparent.