Comparison of antioxidant effectiveness of lipoic acid and dihydrolipoic acid

✍ Scribed by Feng Zhao; Zai-Qun Liu

• Book ID: 102298599
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 154 KB
• Volume: 25
• Category: Article
• ISSN: 1095-6670
• DOI: 10.1002/jbt.20378

✦ Synopsis

The abilities of dihydrolipoic acid (DHLA) to scavenge peroxynitrite (ONOO -), galvinoxyl radical, 2,2 -azinobis(3-ethylbenzothiazoline-6sulfonate) cation radical (ABTS +• ), and 2,2 -diphenyl-1-picrylhydrazyl radical (DPPH) were higher than those of lipoic acid (LA). The effectiveness of DHLA to protect methyl linoleate against 2,2 -azobis(2amidinopropane hydrochloride) (AAPH)-induced oxidation was about 2.2-fold higher than that of LA, and DHLA can retard the autoxidation of linoleic acid (LH) in the β-carotene-bleaching test. DHLA can also trap ∼0.6 radicals in AAPH-induced oxidation of LH. Moreover, DHLA can scavenge ∼2.0 radicals in AAPHinduced oxidation of DNA and AAPH-induced hemolysis of erythrocytes, whereas LA can scavenge ∼1.5 radicals at the same experimental conditions. DHLA can protect erythrocytes against hemin-induced hemolysis, but accelerate the degradation of DNA in the presence of Cu 2+ . Therefore, the antioxidant capacity of -SH in DHLA is higher than S-S in LA.