Da. Pearson et al., INHIBITION OF ENDOTHELIAL CELL-MEDIATED OXIDATION OF LOW-DENSITY-LIPOPROTEIN BY ROSEMARY AND PLANT PHENOLICS, Journal of agricultural and food chemistry, 45(3), 1997, pp. 578-582
Plant-derived phenolic compounds possess antioxidant activity that may
be applicable to such diverse areas as human health and the preservat
ion of food lipids. The potential antioxidant activities of a variety
of plant phenolics were investigated using human aortic endothelial ce
lls (HAEC) to mediate the oxidation of low-density lipoprotein(LDL). C
arnosic acid, carnosol, and rosmarinic acid, present in rosemary extra
ct, and thymol, carvacrol, and zingerone, present in thyme, origanum,
and ginger, were individually incubated with HAEC and LDL for 12 h. Th
e extent of oxidation was determined spectrophotometrically by measuri
ng absorbance (at 234 nn) of conjugated dienes. All antioxidants produ
ced dose-dependent inhibition of LDL oxidation. Their relative antioxi
dant activities decreased in the order carnosol > carnosic acid approx
imate to rosmarinic acid >>> thymol > carvacrol > zingerone. The antio
xidant activity of these plant phenolics in the HAEC system suggests t
hat they may have potential benefits in human health.