ANTIOXIDANT ACTIVITY OF POLYPHENOLS FROM HYPOGYMNIA TAVARESII D. HAWKSW. & P. JAMES.

Química Nova

Barrera, Jaime Bermejo¹  Instituto de Productos Naturales y Agrobiología, Tenerife, España¹  Rosas, Francisco J. Estevez¹  Universidad de Las Palmas de Gran Canaria, Gran Canaria, Spain¹  Hernández, Josefa Caballero¹  Marante, Francisco J. Toledo¹  Pérez, Elsa M. Rodríguez¹ 

关键词:  Hypogymnia;    tavaresii;    lichen;    depsides;    depsidones;    scavengers;   

DOI  :  10.5935/0100-4042.20160053

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

Lichen substances have more than one phenolic hydroxyl group attached to one or more benzene rings, thus qualifying them as polyphenols. The secondary metabolites isolated from the lichen H. tavaresii have been studied in a bid to find compounds protective against oxidative stress and free radical-induced damage. The compounds were identified based on their MS and 1H-NMR spectra as well as retention factors of TLC analysis. In addition to the previously described metabolites (atranorin, chloroatranorin, physodic and physodalic acids) of H. tavaresii, a further three were identified in its thalli: 2´-O-methylphysodone, isophysodic and ursolic acids. The newly identified compounds of H. tavaresii thalli may be useful in the chemotaxonomic classification of this species. Antioxidant effectiveness of the acetone extract's fractions was measured. The compounds of the active fractions were purified and exhibited 180-800 fold less radical scavenging activity than the reference substance α-(+)-tocopherol in a DPPH• model expressed by IC50 values.

【 授权许可】

Unknown