These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: [Effect of antioxidants on the psoralen photo-oxidation process].
    Author: Potapenko AIa, Bezdetnaia LN, Wunderlich Z, Sukhorukov VL, Pliquett F.
    Journal: Biofizika; 1986; 31(4):549-54. PubMed ID: 3756226.
    Abstract:
    Psoralens are capable of photosensitizing oxidation of unsaturated fatty acids due to the two-stage mechanism. During the first (light) stage psoralen solution in ethanol undergoes photooxidation under UV-irradiation (366 nm). At the second (dark) stage the addition of photooxidized psoralen (POP) to the aqueous solution of liposomes is followed by lipid oxidation. Antioxidants inhibited the UV-stage, but did not influence the dark one. Neither spectrophotometry, nor spectrofluorometry could detect photoproducts of psoralen involved in the two-stage oxidation of lipids. However, mixing of ethanol solution of POP with water resulted in the flash of chemiluminescence. The inhibition constants by antioxidants of photoproducts formation which are active in the two-stage oxidation of lipids were estimated by chemiluminescence. Stern--Volmer's constants for antioxidants: 2,6-dimethyl-3,5-diacetyl-1,4-dihydropyridine (DHP), 6-hydroxy-2,2,5,7,8-pentamethylchroman (chromanol--C1), water soluble sodium phenozan and butilated hydroxytoluen (ionol) appeared to be (7.4 +/- 2.2) X 10(3) M-1, (4.4 +/- 1.0) X 10(3) M-1, (3.3 +/- 0.7) X 10(3) M-1, (4.5 +/- 2.5) X 10(2) M-1, respectively. The biological importance of these two-stage oxidation photosensitized by furocoumarins is discussed.
    [Abstract] [Full Text] [Related] [New Search]