麦角固醇的光氧化作用：单线态氧的抗氧化剂、光敏剂或猝灭剂的间接检测

Photo-oxidation of ergosterol: indirect detection of antioxidants photosensitizers or quenchers of singlet oxygen.

作者信息

Lagunes Irene, Trigos Ángel

机构信息

Doctorado en Ciencias Biomédicas, Universidad Veracruzana, Av. Luis Castelazo Ayala s/n, Col. Industrial Ánimas, C.P. 91190 Xalapa, Veracruz, Mexico.

Laboratorio de Alta Tecnología de Xalapa (LATEX), Calle Médicos 5, Col. Unidad del Bosque, C.P. 91010 Xalapa, Veracruz, Mexico; Instituto de Ciencias Básicas, Universidad Veracruzana, Av. Luis Castelazo Ayala s/n, Col. Industrial Ánimas, C.P. 91190 Xalapa, Veracruz, Mexico.

出版信息

J Photochem Photobiol B. 2015 Apr;145:30-4. doi: 10.1016/j.jphotobiol.2015.02.014. Epub 2015 Feb 27.

DOI:10.1016/j.jphotobiol.2015.02.014

PMID:25756399

Abstract

Consumption of antioxidant supplements is associated to prevention of several diseases. However, recent studies suggest that antioxidants, besides scavenge free radicals could lead development of tumors. Due to conflicting reports on the antioxidant benefits, the capacity to photosensitize the generation of singlet oxygen of seven natural antioxidants was evaluated through photo-oxidation of ergosterol which proved to be an efficient method of indirect detection of singlet oxygen. Our results showed that curcumin, resveratrol and quercetin have pro-oxidant activity due they act as photosensitizers in generation of singlet oxygen. In addition, we observed that genistein, naringenin, β-carotene and gallic acid besides their antioxidant activity against ROS radicals, are capable of quenching ROS non-radicals as singlet oxygen. Finally, our results allow us to propose a new approach in classification of natural antioxidants scavengers of free radicals, based on their activity as quenchers of singlet oxygen or as photosensitizers in singlet oxygen generation.

摘要

食用抗氧化剂补充剂与预防多种疾病有关。然而，最近的研究表明，抗氧化剂除了清除自由基外，还可能导致肿瘤的发生。由于关于抗氧化剂益处的报道相互矛盾，通过麦角固醇的光氧化评估了七种天然抗氧化剂使单线态氧生成的光敏化能力，这被证明是间接检测单线态氧的有效方法。我们的结果表明，姜黄素、白藜芦醇和槲皮素具有促氧化活性，因为它们在单线态氧的生成中充当光敏剂。此外，我们观察到，染料木黄酮、柚皮素、β-胡萝卜素和没食子酸除了对活性氧自由基具有抗氧化活性外，还能够淬灭单线态氧等非自由基活性氧。最后，我们的结果使我们能够基于天然抗氧化剂作为单线态氧淬灭剂或单线态氧生成中的光敏剂的活性，提出一种对自由基清除剂进行分类的新方法。