(22) Two stored forms of [H.sub.2]S have been identified: acid-labile sulfur and bound sulfane sulfur.
Does bound sulfane sulfur release enough [H.sub.2]S with appropriate timing for the exertion of [H.sub.2]S activity?
Krishnamurti, "Experimental diabetes increases the formation of sulfane
by transsulfuration and inactivation of tyrosine aminotransferase in cytosols from rat liver," Metabolism, vol.
Beinert, "Semi-micro methods for analysis of labile sulfide and of labile sulfide plus sulfane
sulfur in unusually stable iron-sulfur proteins," Analytical Biochemistry, vol.
There are many ligands used on the cloud point extraction/preconcentration of lead reported in the literature, such as methyl-2-pyridylketone oxime (MPKO) (GHAEDI et al., 2008), dimethylglyoxime (DMG) (BAKIRCIOGLU, 2012), 1-(2-thiazolylazo)2-naphthol (TAN) (CHEN; TEO, 2001; SILVA; ROLDAN, 2009), bis((1H-benzo [d] imidazol2yl)ethyl) sulfane
(BIES) (GHAEDI et al., 2009), dithizone (WEN et al., 2012), O,Odiethyldithiophosphate (DDTP) (BORGES et al., 2003; MANZOORI; BAVILI-TABRIZI, 2002) and 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (5-Br-PADAP) (CHEN et al., 2005).
In this process, the deposits of inorganic materials in the peat bogs were submitted to the influence of humic acids and decomposition products of the vegetable matter: carbon dioxide, sulfane
, ammonia and hydrogen.
[H.sub.2]S can store its sulfur group with iron (acid labile sulfur)  or in sulfane
sulfur (a persulfide)  in mammalian tissues.
In the past years, a growing body of evidence suggests a concept by which intracellular [H.sub.2]S concentrations are determined by (1) its enzymatic production; (2) its intracellular storage as bound sulfane
sulfur; and (3) its oxidative degradation by mitochondria.