Antioxidant activities of carotenes and xanthophylls

Abstract

The purpose of this study was to assess the relative antioxidant activities of a range of carotenes and xanthophylls through the extent of their abilities to scavenge the ABTS "+ radical cation. The results show that the relative abilities of the carotenoids to scavenge the ABTS "÷ radical cation are influenced by the presence of functional groups with increasing polarities, such as carbonyl and hydroxyl groups, in the terminal rings, as well as by the number of conjugated double bonds.

In vitro antiproliferative, apoptotic and antioxidant activities of punicalagin, ellagic acid and a total pomegranate tannin extract are enhanced in combination with other polyphenols as found in pomegranate juice

“…The assay was performed as previously reported [22]. Briefly, 2V 2V-azinobis(3-thylbenzothiazline-6-sulfonic acid)-diammonium salt (ABTS) radical cations were prepared by adding solid manganese dioxide (80 mg) to a 5-mM aqueous stock solution of ABTS + (20 ml using a 75-mM Na/K buffer of pH 7).…”

Effect of edible coatings on bioactive compounds and antioxidant capacity of tomatoes at different maturity stages

“…TEAC value was determined according to Miller et al (1996) and Re et al (1999). ABTS •+ cation was generated through the interaction of 19.2 mg of ABTS (2′2-azino-bis (3-ethylbenzotriazoline-6-sulfonic acid)) dissolved in 5 mL of HPLC-grade water and 88 μL of potassium persulfate (K 2 S 2 O 8 ) (0.0378 gmL −1 ).…”

Lycopene and prostate cancer

“…Interest has been heightened in lycopene, in particular, as it has a large number of double bonds and thus has been found to be the most potent scavenger of oxygen free radicals of all the carotenoids. 48 Lycopene has been demonstrated to not only scavenge oxygen free radical species, for example peroxyl radicals, but also interact with reactive oxygen species such as hydrogen peroxide and nitrogen dioxide 49 -51 and in this manner protect cells from oxidative damage. Interestingly lycopene was found to be twice as efficient as beta-carotene in scavenging for nitrogen dioxide.…”