Marchantinquinone, isolated from Reboulia hemisphaerica, as inhibitor of lipid peroxidation and as free radical scavenger.
The antioxidant effect of marchantinquinone was studied using various models. Marchantinquinone inhibited Fe(2+)-induced lipid peroxidation in rat brain homogenate in a concentration-dependent manner with an IC50 15.3 +/- 2.9 microM. Marchantinquinone was less effective than alpha-tocopherol and BHT in reducing the stable free radical diphenyl-2-picrylhydrazyl (DPPH). The IC0.200 were 37.5 +/- 2.5, 9.2 +/- 1.6 and 14.5 +/- 2.5 microM, respectively. Marchantinquinone also scavenged peroxyl radical derived from 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) in aqueous system with a stoichiometric factor of 0.9 +/- 0.1. Furthermore, it prevented conjugated-diene formation and apolipoprotein B (apo B) oxidation of LDL. However, marchantinquinone did not chelate Fe2+ or possess superoxide anion and hydroxyl radical scavenging activity. It also did not scavenge 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN)-derived peroxyl radical in hexane. These results indicate that marchantinquinone may be an effective antioxidant and can protect rat brain homogenate and LDL against oxidation.
Ko
F N
FN
Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan.
Liao
C H
CH
Wu
C L
CL
D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification*; D001632:Bibenzyls / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D019068:Bryopsida / Q000737:chemistry*; D002084:Butylated Hydroxytoluene / Q000494:pharmacology; D003574:Cytochrome c Group / Q000378:metabolism; D003855:Deoxyribose / Q000378:metabolism; D004988:Ethers, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D016166:Free Radical Scavengers; D017665:Hydroxyl Radical / Q000378:metabolism; D066298:In Vitro Techniques; D015227:Lipid Peroxidation / Q000187:drug effects*; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D017208:Rats, Wistar; D013481:Superoxides / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000494:pharmacology
D000975:Antioxidants; D001632:Bibenzyls; D003574:Cytochrome c Group; D004988:Ethers, Cyclic; D016166:Free Radical Scavengers; D008077:Lipoproteins, LDL; D017392:Thiobarbituric Acid Reactive Substances; C097634:marchantinquinone; D013481:Superoxides; D014810:Vitamin E; D002084:Butylated Hydroxytoluene; D017665:Hydroxyl Radical; D003855:Deoxyribose