Radical Scavenging Activities of Plant Food of Alkyl-oxy and Superoxide Radicals

Abstract

The spin trapping ability against alkyl-oxy and superoxide radicals was examined using a new reagent 5-(2,2-dimethy-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO), a colorless crystalline that is very soluble in aqueous solution. For careful detection of spin adducts, we used borosilicate ESR flat cells. We examined plant specimens from teas, vegetables and fruits. CYPMPO successfully trapped alkyl-oxy and superoxide radicals in the plant extracts. We generated very pure alkyl-oxy radicals by illuminating phosphate buffer solution containing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and CYPMPO with Hg-Xe arc lamp. Superoxide radicals were similarly generated using hypoxanthine (HPX), diethylene-triamine-pentaacetic acid (DTPA), CYPMPO and xanthenes oxidase (XOD). The spin adducts by CYPMPO were sensitive and very stable. The trapping activity for the alkyl-oxy and superoxide radicals was measured by the 2-amino-5-{[2-[(carboxymethyl)amino]-1-(mercaptomethyl)-2-oxoethyl]amino} 5-oxopentanoic acid (GSH) and superoxide dismutase (SOD) equivalents, respectively. Thus, CYPMPO is useful for its high capability of radical trapping.