Journal of Photosciences

Singlet Oxygen Quenching by Deoxygadusol and Related Mycosporine-Like Amino Acids from Phytoplankton Prorocentrum micans

Volume 11(2004), 77-81 page

저자: Hwa-Jin Suh, Hyun-Woo Lee, and Jin Jung

   11-2-77.pdf (75.7K)

Keywords: singlet oxygen (1O2) quenching  1O2 reaction rate constant  photooxidation  mycosporine-like amino acid  deoxygadusol

Deoxygadusol (DG) and structurally related mycosporine-like amino acids, i.e. mycosporine glycine (MG) and mycosporine taurine (MT), were isolated from phytoplankton Prorocentrum micans and studied for the reactivity toward singlet oxygen. These water-soluble compounds with a cyclohexenone chromophore were all shown to be highly effective in quenching singlet oxygen (1O2), with the efficiencies being significantly larger compared with histidine, a well-known 1O2 quencher. The 1O2 reaction rate constant (kQ) of DG was determined to be 5.4 × 107 M-1s-1 by a steady state method based on competitive inhibition of rubrene oxidation. The feasibility of this method was confirmed by estimating the kQ values for MG and two other quenchers, furfuryl alcohol and 1,4-diazabicyclo [2,2,2]octane, and comparing with those values determined by the time-resolved 1O2 decay method in the previous work.