The Antioxidant capacity and hydrogen peroxide formation by black and orange carrots: Black and orange carrots

Anthocyanins are powerful antioxidants with numerous beneficial health effects. However, their autoxidation may produce hydrogen peroxide. Black carrots owe their colour to the high anthocyanin content. The aim of this study was to compare the antioxidant capacity of and hydrogen generation by black and orange carrots. Black carrots were found to have a significantly higher anthocyanin content and antioxidant capacity estimated by the FRAP assay, DPPH scavenging and ABTS• scavenging. Carrot, like other vegetables, generates hydrogen peroxide upon cooking. Black carrots generated much more hydrogen peroxide than orange carrots (55.0 ± 2.6 µM vs 6.0 ± 2.1 µM in phosphate buffer, 8.7 ± 1.2 vs 0.3 ± 0.1 µM in water, in 1:5 (w/v) homogenates. These small amounts of hydrogen peroxide are not likely to exert deleterious health effects but may have antimicrobial activity

Oxidative Modification of Blood Serum Proteins in Multiple Sclerosis after Interferon Beta and Melatonin Treatment

Multiple sclerosis (MS) is a disease involving oxidative stress (OS). This study was aimed at examination of the effect of melatonin supplementation on OS parameters, especially oxidative protein modifications of blood serum proteins, in MS patients. The study included 11 control subjects, 14 de novo diagnosed MS patients with the relapsing-remitting form of MS (RRMS), 36 patients with RRMS receiving interferon beta-1b (250 μg every other day), and 25 RRMS patients receiving interferon beta-1b plus melatonin (5 mg daily). The levels of N′-formylkynurenine, kynurenine, dityrosine, carbonyl groups, advanced glycation products (AGEs), advanced oxidation protein products (AOPP), and malondialdehyde were elevated in nontreated RRSM patients. N′-Formylkynurenine, kynurenine, AGEs, and carbonyl contents were decreased only in the group treated with interferon beta plus melatonin, while dityrosine and AOPP contents were decreased both in the group of patients treated with interferon beta and in the group treated with interferon beta-1b plus melatonin. These results demonstrate that melatonin ameliorates OS in MS patients supporting the view that combined administration of interferon beta-1b and melatonin can be more effective in reducing OS in MS patients than interferon beta-1b alone