title: Photosensitization of hypomycin B--a novel perylenequinonoid pigment with only one intramolecular hydrogen bond.
abstract: Electron spin resonance technique and spin-trapping methods were used to determine the photoproduction of 1O2 and O2.- by hypomycin B (HMB), a novel perylenequinonoid pigment (PQP) possessing only one hydroxyl group. It was found that the yields of 1O2 and O2.- for HMB were comparable to those for hypocrellin A, a typical natural PQP with good photosensitivity. In addition, the absorption and fluorescence spectra for HMB were investigated. The pKa values in the ground and excited states of HMB were determined to be 8.94 and 5.54, respectively. Thus, the photodynamic mechanisms of HMB may involve not only the photogeneration of 1O2 and O2.- but also the light-induced acidification. Consequently, HMB is proposed to be a good photodynamic therapeutic agent.
authors.affiliation: Laboratory for Computational Biology, Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Zibo University, Zibo, People's Republic of China. zhysdtu@jn-public.sd.cninfo.net
authors.forename: H Y
authors.initials: HY
authors.lastname: Zhang
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.forename: W Z
authors.initials: WZ
authors.lastname: Liu
authors.forename: J L
authors.initials: JL
authors.lastname: Xie
mesh_terms: D006801:Humans; D006860:Hydrogen Bonding; D066298:In Vitro Techniques; D010100:Oxygen / Q000737:chemistry; D010569:Perylene / Q000031:analogs & derivatives / Q000737:chemistry* / Q000528:radiation effects*; D019800:Phenol; D010777:Photochemistry; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000737:chemistry* / Q000528:radiation effects*; D011809:Quinones / Q000737:chemistry* / Q000528:radiation effects*; D026082:Singlet Oxygen; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry; D013481:Superoxides / Q000737:chemistry
chemical_list: D017319:Photosensitizing Agents; D011809:Quinones; C437341:hypomycin B; D013481:Superoxides; D026082:Singlet Oxygen; D019800:Phenol; D010569:Perylene; D010100:Oxygen; C048388:hypocrellin A