title: Synergism between airborne singlet oxygen and a trisubstituted olefin sulfonate for the inactivation of bacteria.
abstract: The reactivity of a trisubstituted alkene surfactant (8-methylnon-7-ene-1 sulfonate, 1) to airborne singlet oxygen in a solution containing E. coli was examined. Surfactant 1 was prepared by a Strecker-type reaction of 9-bromo-2-methylnon-2-ene with sodium sulfite. Submicellar concentrations of 1 were used that reacted with singlet oxygen by an "ene" reaction to yield two hydroperoxides (7-hydroperoxy-8-methylnon-8-ene-1 sulfonate and (E)-8-hydroperoxy-8-methylnon-6-ene-1 sulfonate) in a 4:1 ratio. Exchanging the H2O solution for D2O where the lifetime of solution-phase singlet oxygen increases by 20-fold led to an ∼2-fold increase in the yield of hydroperoxides pointing to surface activity of singlet oxygen with the surfactant in a partially solvated state. In this airborne singlet oxygen reaction, E. coli inactivation was monitored in the presence and absence of 1 and by a LIVE/DEAD cell permeabilization assay. It was shown that the surfactant has low dark toxicity with respect to the bacteria, but in the presence of airborne singlet oxygen, it produces a synergistic enhancement of the bacterial inactivation. How the ene-derived surfactant hydroperoxides can provoke (1)O2 toxicity and be of general utility is discussed.
authors.affiliation: Department of Chemistry and Graduate Center, City University of New York, Brooklyn College , Brooklyn, New York 11210, United States.
authors.forename: Rajib
authors.initials: R
authors.lastname: Choudhury
authors.forename: Alexander
authors.initials: A
authors.lastname: Greer
mesh_terms: D000476:Alkanesulfonates / Q000737:chemistry*; D004926:Escherichia coli / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D015394:Molecular Structure; D026082:Singlet Oxygen / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: C000593115:8-methylnon-7-ene-1 sulfonate; D000476:Alkanesulfonates; D013501:Surface-Active Agents; D026082:Singlet Oxygen; D006861:Hydrogen Peroxide