Methylene Blue Photosensitized Oxidation of Cysteine Sulfinic Acid and Other Sulfinates: The Involvement of Singlet Oxygen and the Azide Paradox

The Interaction of Hypotaurine and Other Sulfinates with Reactive Oxygen and Nitrogen Species: A Survey of Reaction Mechanisms

“…In all experiments performed to detect the yield in the production of RSO 3 -, TAU and CA, from RSO 2 -, HTAU and CSA, a different behaviour has always been reported between the HTAU-and CSA-derived sulfonyl radical (Pecci et al 2000;Fontana et al 2005 and2006;Baseggio Conrado et al 2014 and2015). It has been shown that only a fraction of the depleted CSA was oxidized to CA with a yield of around 17%, compared with the almost total oxidation of HTAU in TAU (Baseggio Conrado et al 2014).…”

“…• OH) and singlet oxygen have shown high direct reactivity leading to TAU formation (Pecci et al 1999 and2000;Arouma et al 1988). This is in spite of low direct reactivity between hydrogen peroxide (H 2 O 2 ), superoxide anion (O 2 •-) and RSO 2 - (Aruoma et al 1998).…”

“…The mechanisms involved in the interaction of the reactive oxygen (ROS) and nitrogen species (RNS) with RSO 2 -, HTAU and CSA, have only recently been investigated in depth (Fontana et al 2005;Baseggio Conrado et al 2014). In particular, starting from the findings of Cavallini and coworkers (Ricci et al 1978;Pecci et al 1999 and2000) and subsequently, through experiments performed to understand whether peroxynitrite could be included in the biologically relevant reactive species capable of oxidizing RSO 2 -, it has been possible to highlight the reaction pathway mechanism of RSO 2 -leading to RSO 3 - (Fontana et al 2005 and2006). …”

A new generation of biocides for control of crustacea in fish farms

“…The type I mechanism produces a radical intermediate by direct interaction of the light excited photosensitiser (MB*) with the substrate via electron transfer. The type II mechanism involves energy transfer from the photo-excited state of the photosensitiser to oxygen with the production of singlet oxygen [33].…”

Photo-dynamic biocidal action of methylene blue and hydrogen peroxide on the cyanobacterium Synechococcus leopoliensis under visible light irradiation

“…The type I mechanism produces a radical intermediate by direct interaction of the light excited photosensitiser (MB*) with the substrate via electron transfer. The type II mechanism involves energy transfer from the photo-excited state of the photosensitiser to oxygen with the production of singlet oxygen [42]. In order to assist in determining what mechanism type the current process followed, the system was investigated in an inert atmosphere.…”