Fate and kinetic modeling of reactivity of alkanesulfenic acids and thiosulfinates in model systems and onion homogenates.
The dynamic changes in thiosulfinate profiles were studied in reaction systems containing a crude onion alliinase, S-alk(en)yl-L-cysteine sulfoxide substrates (1) and preformed thiosulfinates (4). Regioisomeric excesses of one of two possible heterologous 4 species (RS(O)SR', where R does not equal R') could be manipulated under conditions where alliinase, 1, and 4 levels were varied. Regioisomeric excesses could be explained by a thiosulfinate (4)/alkanesulfenic acid (2) trapping mechanism, with the greatest control over product profile governed by the rate of 2 generation in the system. The series of reactions existing in this dynamic reaction system was kinetically modeled with reasonable fits to the experimental data. The application of the 4/2 trapping strategy to manipulate thiosulfinate and related organosulfur product profiles in diluted onion homogenates was demonstrated using exogenous MeS(O)SMe (4a), PrS(O)SPr (4c), and AllS(O)SAll (4d) as the preformed thiosulfinate.
Shen
Cunxi
C
Department of Food Science, University of Wisconsin-Madison, Babcock Hall, 1605 Linden Drive, Madison, WI 53706, USA.
Hong
Zongxuan
Z
Parkin
Kirk L
KL
D000473:Alkanes / Q000737:chemistry / Q000378:metabolism*; D000490:Allium / Q000737:chemistry*; D013437:Carbon-Sulfur Lyases / Q000378:metabolism; D007700:Kinetics; D008956:Models, Chemical; D013434:Sulfenic Acids / Q000737:chemistry / Q000378:metabolism*; D013441:Sulfinic Acids / Q000737:chemistry / Q000378:metabolism*
D000473:Alkanes; D013434:Sulfenic Acids; D013441:Sulfinic Acids; C100040:thiosulfinic acids; D013437:Carbon-Sulfur Lyases; C019243:alliin lyase