(S)-Trolox, an analogue of vitamin E, substitutes the phytyl chain with a carboxyl group. This compound serves as a model substance in structural studies and as a standard for assessing antioxidant activity. Moreover, (S)-Trolox exhibits potent and specific neuroprotective and antioxidant properties.
Cyanidin 3-O-arabinoside is an anthocyanin antioxidant that has been found in eggplant. It scavenges radicals in a Trolox equivalent antioxidant capacity (TEAC) assay.
Resveratrol-3-O-sulfate is a metabolite of resveratrol . In U-937 cells stimulated with LPS, resveratrol-3-O-sulfate (1 μM) decreases the expression of IL-1α, IL-1β, and IL-6 by 61.2, 76.6, and 42.2%, respectively, and decreases the release of TNF-α and IL-6 to similar levels as resveratrol. It has antioxidant activity in a Trolox assay, dose-dependently decreases growth of Caco-2 colorectal adenocarcinoma cells when used at concentrations ranging from 10 to 100 μM, and induces apoptosis at concentrations of 25 and 50 μM. Resveratrol-3-O-sulfate also displaces rosiglitazone from the outer mitochondrial protein mitoNEET (IC50 = 3.36 μM for the human protein), indicating that it binds to the thiazolidine-2,4-dione (TZD) binding pocket.