Premium
Antioxidant and free radical scavenging activities of Misodendrum punctulatum , myzodendrone and structurally related phenols
Author(s) -
Desmarchelier Cristian,
del V. Pacciaroni Adriana,
AbateDaga Daniel,
Coussio Jorge,
Gil Roberto R.,
Silva Gloria L.
Publication year - 2005
Publication title -
phytotherapy research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.019
H-Index - 129
eISSN - 1099-1573
pISSN - 0951-418X
DOI - 10.1002/ptr.1786
Subject(s) - antioxidant , phenols , scavenging , chemistry , traditional medicine , organic chemistry , medicine
Abstract The peroxyl radical scavenging activity of a dry methanol extract of Misodendrum punctulatum was determined by means of luminol‐enhanced chemiluminescence assay, allowing to calculate the total reactive antioxidant potential (TRAP) index equal to 239 ± 26 µ m , expressed in Trolox equivalents. The flavan‐3‐ol catechin (1) and the phenylbutanone derivative myzodendrone (2) were identified through assay‐guided fractionation as active metabolites present in the extract, and their structures were elucidated by chemical and spectroscopic analysis. Three other structurally related synthetic phenols, dehydrozingerone (3), zingerone (4) and myzodendrone aglycone (5), were also analysed using this method. Compounds 1 and 2 were highly effective as free radical scavengers (TRAP = 1257 µ m and 1018 µ m , respectively) when compared with Trolox (TRAP = 144 µ m ), used as a standard. Compounds 3 and 5 were also active showing TRAP values of 229 µ m and 219 µ m , respectively, similarly to that observed for the dry extract. On the other hand, 4 was inactive. Catechin (1) also reduced the production of thiobarbituric acid reactive substances (TBARS) in rat liver homogenates, with IC 50 = 26 µg/mL, superior to that obtained for Trolox, IC 50 = 73 µg/mL. Compounds 2 and 5 showed IC 50 values > 1000 µg/mL, while no activity could be observed for 3, 4, or the extract. Copyright © 2005 John Wiley & Sons, Ltd.